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The pathways through which mature blood cells in the bone marrow (BM) enter the blood stream and exit the BM, hematopoietic stem cells in the peripheral blood return to the BM, and other substances exit the BM are referred to as the marrow–blood barrier (MBB). This barrier plays an important role in the restrictive sequestration of blood cells, the release of mature blood cells, and the entry and exit of particulate matter. In some blood diseases and tumors, the presence of immature cells in the blood suggests that the MBB is damaged, mainly manifesting as increased permeability, especially in angiogenesis. Some imaging methods have been used to monitor the integrity and permeability of the MBB, such as DCE-MRI, IVIM, ASL, BOLD-MRI, and microfluidic devices, which contribute to understanding the process of related diseases and developing appropriate treatment options. In this review, we briefly introduce the theory of MBB imaging modalities along with their clinical applications. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the clinical efficacy of compound polymyxin B ointment for treating chronic refractory wounds. A retrospective analysis was performed on 111 patients who underwent chronic refractory wound treatment. Patients were divided into 2 groups, with 45 patients included in the experimental group (compound polymyxin B group) and 66 patients included in the control group (silver sulfadiazine group). After thorough debridement in both groups, either compound polymyxin B ointment or silver sulfadiazine cream was evenly applied to the patient's wound and covered with sterile gauze. In both groups, dressing changes were dependent on the wound's condition and secretions. Using the Bates-Jensen Wound Assessment Tool (BWAT), patients in both groups were scored, after which wound healing, infection, and healing time were compared. There was no significant difference in BWAT scores between the 2 groups on the 7th or 14th day; however, on the 21st day, the BWAT score in the experimental group was significantly lower than that of the control group. The difference was statistically significant (P <.05). There was no significant difference in the BWAT-I scores between the 2 groups on the seventh day. The healing time in the experimental group was significantly shorter than that of the control group, and the difference was statistically significant (P <.05). For the treatment of chronic refractory wounds, thorough debridement followed by compound polymyxin B ointment topical application can reduce and control wound infection effectively and accelerate the process of wound repair. [ABSTRACT FROM AUTHOR]

Methylglyoxal (MGO) is a highly reactive dicarbonyl compound formed during hyperglycaemia. MGO combines with proteins to form advanced glycation end products (AGEs), leading to cellular dysfunction and organ damage. In type 2 diabetes mellitus (T2DM), the higher the plasma MGO concentration, the higher the lower extremity amputation rate. Here, we aimed to identify the mechanisms of MGO‐induced dysfunction. We observed that the accumulation of MGO‐derived AGEs in human diabetic wounds increased, whereas the expression of glyoxalase 1 (GLO1), a key metabolic enzyme of MGO, decreased. We show for the first time that topical application of pyridoxamine (PM), a natural vitamin B6 analogue, reduced the accumulation of MGO‐derived AGEs in the wound tissue of type‐2 diabetic mice, promoted the influx of macrophages in the early stage of tissue repair, improved the dysfunctional inflammatory response, and accelerated wound healing. In vitro, MGO damaged the phagocytic functions of M1‐like macrophages induced by lipopolysaccharide (LPS), but not those of M0‐like macrophages induced by PMA or of M2‐like macrophages induced by interleukins 4 (IL‐4) and 13 (IL‐13); the impaired phagocytosis of M1‐like macrophages was rescued by PM administration. These findings suggest that the increase in MGO metabolism in vivo might contribute to macrophage dysfunction, thereby affecting wound healing. Our results indicate that PM may be a novel therapeutic approach for treating diabetic wounds. MGO forms protein adducts that cause macrophage dysfunction. These adducts cause cell and organ dysfunction that is common in diabetes. Pyridoxamine scavenges MGO to ameliorate this dysfunction, promoting wound healing. Pyridoxamine could be used therapeutically to treat non‐healing diabetic wounds. [ABSTRACT FROM AUTHOR]

Objective: To explore the regulation relationship between miR-181a-3p and BMP10, and their mechanism of osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (MSCs). Methods: After osteogenic induction of MSCs, the ALP activity was detected by ELISA. The expression of miRNA-181a-3p and BMP10 was detected by RT-qPCR, and the protein levels of BMP10 and osteogenic differentiation marker proteins ALK and RUNX2 were detected by Western blot. The TargetScan online website was used to predict the putative target of miR-181a-3p, and dual luciferase reporter assay was performed to validate the targeting relationship between miR-181a-3p and BMP10. Results: In osteogenic differentiation of MSCs, ALP activity, the level of ALK and RUNX2 was evidently increased (p <.05), and the expression of miR-181a-3p was significantly downregulated (p <.05). Moreover, overexpression of miR-181a-3p obviously decreased the expression of BMP10 (p <.05), miR-181a-3p knockdown increased the expression of BMP10 prominently (p <.05). The transfection of miR-181a-3p mimics resulted in significantly downregulation of ALP activity and RUNX2 protein expression in MSCs (p <.05). In addition, overexpression of BMP10 could reverse the inhibitory effect of miR-181a-3p on osteogenic differentiation (p <.05). Conclusions: In conclusion, we found that miR-181a-3p inhibited osteogenic differentiation of MCSs by targeting BMP10. [ABSTRACT FROM AUTHOR]

Objectives: Treating chronic cutaneous wounds is challenging, and debridement is a central concept in treating them. Studies have shown that CO 2 laser debridement can control local infection and promote the wound healing process. The present study aimed to investigate the efficacy and safety of fully ablative CO 2 laser debridement compared to routine surgical debridement in the treatment of chronic wounds., Methods: The retrospective cohort study was conducted on patients with chronic (>1 month) cutaneous wounds (≥1 cm 2 ) between December 1, 2017, and December 1, 2020, in the Wound Healing Center at Shanghai Ruijin Hospital, China. Patients treated with CO 2 laser debridement with a DEKA SmartXide2 C80 (DEKA) (the CO 2 laser group) were compared with matched control patients with similar baseline characteristics who had undergone routine surgical debridement (the routine group). The primary outcome was time-to-heal (days) for chronic wounds in two groups, and secondary outcomes included the wound area and BWAT (Bates-Jensen wound assessment tool) score before treatment, and at 1, 2, 3, and 4 weeks after treatment., Results: The study included 164 patients (82 in the CO 2 laser group and 82 matched in the routine group). The time-to-heal for patients in the CO 2 laser group (41.30 ± 17.11) was significantly shorter than that of the patients in the routine group (48.51 ± 24.32) (p = 0.015). At 3 and 4 weeks after treatment, the absolute wound area of the CO 2 laser group was significantly smaller than that of the routine group. Also, the CO 2 laser group exhibited a significantly lower relative area at 2, 3, and 4 weeks after treatment. The CO 2 laser group yielded significantly lower BWAT scores at 2, 3, and 4 weeks after treatment. Additionally, the relative BWAT score was significantly lower in the CO 2 laser group than the relative scores in the routine group at 2, 3, and 4 weeks after treatment. No adverse events related to the treatments were observed in either group during the study period., Conclusions: The present study has shown that fully ablative CO 2 laser debridement has several advantages over routine sharp surgical debridement. It is superior at ameliorating wound status and reducing wound area, and it also significantly reduces the time-to-heal for chronic wounds, without causing any adverse events., (© 2021 Wiley Periodicals LLC.)

Transcranial direct current stimulation (tDCS) delivers weak current into the brain to modulate neural activities. Many methods have been proposed to determine electrode positions and stimulation intensities. Due to the trade-off between intensity and focality, it is actually a multi-objective optimization problem that has a set of optimal solutions. However, traditional methods can produce only one solution at each time, and many parameters need to be determined by experience. In this study, we proposed the nondominated sorting genetic algorithm II (NSGA-II) to solve the current optimization problem of multi-electrode tDCS. We also compared the representative solutions with LCMV solutions. The result shows that a group of solutions close to the optimal front can be obtained just in only one run without any prior knowledge.

Previous studies have demonstrated that transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (dlPFC) can enhance working memory. However, the mechanism underlying the long-term tDCS is still unclear. This pilot study aims to examine neurotransmitters such as gamma-aminobutyric (GABA) and Glx (a measure of glutamate and glutamine combined) and working memory in response to the long-term anodal tDCS over dlPFC. Six healthy, right-handed young adults enrolled in this study received 2-mA anodal tDCS over dlPFC within 4 weeks. Long-term tDCS means that it was applied 5 times per week for the first two weeks and once for the last two weeks with 30 min each time. The other six participants were enrolled as the control group without stimulation for testing the baseline enhancement of working memory due to learning. The GABA and Glx levels were assessed by Magnetic Resonance Spectroscopy (MRS), while a 3-back task was performed to assess working memory. Data were collected at the beginning of the experiment, after two-week tDCS and at the end of the experiment. We found that the working memory was not significantly enhanced by the first two-week tDCS because the accuracy of response in 3-back was not significantly increased compared to the control group. Meanwhile, there were no significant changes in the levels of GABA. However, the Glx level was found significantly decreased in both 2- and 4-week MRS measurements. The observation that the long-term tDCS causes the decrease of excitatory neurotransmitters implies the different underlying mechanisms between the long-term tDCS and the single one.

Transcranial direct current stimulation (tDCS) is a promising brain modulation technique in clinical application. Computational models of brain current flow have been used to provide better insights into determining the stimulation parameters, but there are only a few studies to validate the numerical simulation model. The purpose of this study is to validate the simulation model of tDCS. A one-/three-layered spherical phantom model was constructed to mimic the human head. The tDCS-induced voltages were measured at different depth in the spherical phantom model with stereotactic-EEG (s-EEG) electrodes. Comparing the measured values with the simulation data from the computational models, we found that the computational and empirically measured electric field distributions on the brain surface is similar and that the deviation between the predicted and measured electric field value becomes larger near the electrode.