Propofol (2,6-diisopropylphenol) is widely used in total intravenous anesthesia. An unknown drug concentration in blood always leads to some side effects in patients with propofol injection. However, ...the drug concentration in the blood is hard to be continuously measured since invasive sampling causes a loss of blood at each measurement. Here, we introduced a virtual surface acoustic wave sensor array (VSAWSA) to non-invasively detect the propofol concentration in blood through exhaled gases. Calibration was conducted by a parallel test using gas chromatography and mass spectrometry (GC-MS) with solid-phase micro-extraction (SPME) for preconcentration. The limit of detection of VSAWSA reached 0.15 nmol/L for propofol. Six cases of clinical trials was conducted to compare the exhaled propofol concentrations to the plasma concentrations controlled by target-controlled infusion (TCI). The calibration by GC-MS ensured the feasibility, reliability, and accuracy of the VSAWSA (R = 0.9904, p <0.001). The clinical monitoring data by VSAWSA showed an excellent consistency with TCI.
Abstract
Background
There is a long latent period for the sciatic nerve block before a satisfactory block is attained. Changes in the temperature of local anesthetics may influence the characters of ...the peripheral nerve block. This study was designed to evaluate the effect of warming ropivacaine on the ultrasound-guided subgluteal sciatic nerve block.
Methods
Fifty-four patients for distal lower limbs surgery were randomly allocated into warming group (group W,
n
= 27) or room tempeture group (group R,
n
= 27) with the ultrasound-guided subgluteal sciatic nerve block. The group W received 30 ml of ropivacaine 0.5% at 30℃ and the group R received 30 ml of ropivacaine 0.5% at 23℃. The sensory and motor blockade were assessed every 2 min for 30 min after injection. The primary outcome was the onset time of limb sensory blockade.
Results
The onset time of sensory blockade was shorter in group W than in group R (16 (16,18) min vs 22 (20,23) min,
p
< 0.001), and the onset time of motor blockade was also shorter in group W than in group R (22 (20,24) min vs 26 (24,28) min,
p
< 0.001). The onset time of sensory blockade for each nerve was shorter in group W than in group R (
p
< 0.001). No obvious differences for the duration of sensory and motor blockade and the patient satisfaction were discovered between both groups. No complications associated with nerve block were observed 2 days after surgery.
Conclusions
Warming ropivacaine 0.5% to 30℃ accelerates the onset time of sensory and motor blockade in the ultrasound-guided subgluteal sciatic nerve block and it has no influence on the duration of sensory and motor blockade.
Trial registration
The trial was registered on October 3, 2022 in the Chinese Clinical Trial Registry (
https://www.chictr.org.cn/bin/project/edit?pid=181104
), registration number ChiCTR2200064350 (03/10/2022).
Ischemic heart diseases is one of the leading causes of death worldwide. Although revascularization timely is an effective therapeutic intervention to salvage the ischemic myocardium, reperfusion ...itself causes additional myocardial injury called ischemia/reperfusion (I/R) injury. Bone marrow-derived mesenchymal stem cells (MSCs) is one of the promising cells to alleviate ischemic myocardial injury. However, this cell therapy is limited by poor MSCs survival after transplantation. Here, we investigated whether sevoflurane preconditioning could promote MSCs to attenuate myocardial I/R injury via transient receptor potential canonical channel 6 (TRPC6)-induced angiogenesis.
The anti-apoptotic effect of sevoflurane preconditioning on MSCs was determined by Annexin V-FITC/propidium iodide staining. TRPC6, hypoxia-inducible factor-1α (HIF-1α), Chemokine receptor 4 (CXCR4) and vascular endothelial growth factor (VEGF) protein expressions and VEGF release from MSCs were determined after hypoxia and reoxygenation (H/R). Small interfering RNA (siRNA) was used to knock down TRPC6 gene expression in MSCs. The angiogenesis of human umbilical vein endothelial cells (HUVECs) co-cultured with MSCs was determined by Matrigel tube formation. Myocardial I/R mouse model was induced by occluding left anterior descending coronary artery for 30 min and then reperfusion. MSCs or sevoflurane preconditioned MSCs were injected around the ligature border zone 5 min before reperfusion. Left ventricle systolic function, infarction size, serum LDH, cTnI and inflammatory cytokines were determined after reperfusion.
Sevoflurane preconditioning up-regulated TRPC6, HIF-1α, CXCR4 and VEGF expressions in MSCs and VEGF release from MSCs under H/R, which were reversed by knockdown of TRPC6 gene using siRNA in MSCs. Furthermore, sevoflurane preconditioning promoted the angiogenic and anti-inflammatory effect of HUVECs co-cultured with MSCs. Sevoflurane preconditioned MSCs improved left ventricle systolic function and alleviated myocardial infarction and inflammation in mice subjected to I/R insult.
The current findings reveal that sevoflurane preconditioned MSCs boost angiogenesis in HUVECs subjected to H/R insult and attenuate myocardial I/R injury, which may be mediated by TRPC6 up-regulated HIF-1α, CXCR4 and VEGF.
Objectives To explore the protection and the mechanism of dexmedetomidine on the oxygen–glucose deprivation (OGD) insults in rat C6 glioma cells.
Methods Cells were subjected to OGD then assessed ...by viability studies. After dexmedetomidine treatment, p‐AKT, hypoxia‐inducible factor (HIF)‐1α, vascular endothelial growth factor (VEGF) and RTP801 expression were measured.
Key findings Three hours of OGD decreased cell viability to 48.8%, which was reversed to 67.4% by 1 µm dexmedetomidine. Hoechst 33342 and propidium iodide double stains showed that the protection of dexmedetomidine was mainly by an anti‐apoptosis effect, which was also strengthened by decreasing caspase‐3 expression. Dexmedetomidine protection was mainly blocked by the I2 imidazoline receptor antagonist idazoxan and BU 224, but not by the α1‐adrenoceptor antagonist prazosin, the α2‐adrenoceptor antagonist yohimbine and RX 821002, or the I1 imidazoline receptor antagonist efaroxan. On the other hand, dexmedetomidine enhanced AKT phosphorylation. Furthermore, the protection of dexmedetomidine was blocked by the PI3K/AKT inhibitor wortmannin. The proteins of HIF‐1α, VEGF and RTP801 were significantly increased by dexmedetomidine treatment.
Conclusions Dexmedetomidine activated the I2 imidazoline receptor‐PI3K/AKT pathway, and up‐regulated HIF‐1α, VEGF and RTP801 expression to protect against OGD‐induced injury in rat C6 cells.
Nerve injury-induced gene expression change in the spinal cord is critical for neuropathic pain genesis. RNA N
-methyladenosine (m
A) modification represents an additional layer of gene regulation. ...We showed that spinal nerve ligation (SNL) upregulated the expression of matrix metallopeptidase 24 (MMP24) protein, but not
mRNA, in the spinal cord neurons. Blocking the SNL-induced upregulation of spinal MMP24 attenuated local neuron sensitization, neuropathic pain development and maintenance. Conversely, mimicking MMP24 increase promoted the spinal ERK activation and produced evoked nociceptive hypersensitivity. Methylated RNA Immunoprecipitation Sequencing (MeRIP-seq) and RNA Immunoprecipitation (RIP) assay indicated the decreased m
A enrichment in the
mRNA under neuropathic pain condition. Moreover, fat-mass and obesity-associated protein (FTO) was colocalized with MMP24 in spinal neurons and shown increased binding to the
mRNA in the spinal cord after SNL. Overexpression or suppression of FTO correlates with promotion or inhibition of MMP24 expression in cultured spinal cord neurons. In conclusion, SNL promoted the m
A eraser FTO binding to the
mRNA, which subsequently facilitated the translation of MMP24 in the spinal cord, and ultimately contributed to neuropathic pain genesis.
Medical education is a demanding lifelong learning process, which includes three tightly connected stages: college education, post-graduate education, and continuous education. Residency, the first ...several years after a college education, is a pivotal time in the development of a qualified doctor. Additionally, residents are the main force that undertakes much of the clinical work in hospitals. Therefore, guaranteeing and improving residents' clinical skills and abilities through the standardized training of resident physicians (STRP) is important. However, compared with other hospitals in the Zhejiang Province, the STRP assessment results of residents in our hospital were not satisfactory in recent years. Therefore, the objective of this study was to find the problems causing the unsatisfactory performance and identify the role of the "Plan-Do-Check-Action" (PDCA) plan in providing a valuable framework for future training.
Relevant studies of STRP in China and abroad were investigated by the literature review. According to published data by the Health Commision of Zhejiang Province, we collected the STRP assessment rsults of a total number of 12,036 residents. The inclusion cretria of these residents include: (1) 3rd-year residents. (2) taking STRP in the Zhejiang Province during 2016-2018 or 2017-2019. (3) the first time taking the clinical practice ability examination (CPAE) in 2018 or 2019. The results of 634 3rd-year residents from The Second Affiliated Hospital of Zhejiang University (SAHZU) were provided by the Department of Medical Education and were analyzed in depth. Three hundred and eight residents from SAHZU received normal training and took the CPAE in 2018, whereas 326 residets received PDCA and took the CPAE in 2019. PDCA is a program designed to improve the performance of residency in SAHZU. It includes the formulation and implementation of specific training plans, the check of effects, and continuous improvements. There was no change in the STRP assessment in these 2 years and the indicator of performance in the STRP assessment was the first pass rate (FPR). Statistical analyses were performed using Pearson's
test, Yates-corrected
test, or Fisher's exact test (SPSS Statistics, version 25). A
-value of < 0.05 was considered significant.
A total number of 6,180 and 5,856 examinees in the Zhejiang Province took the clinical practice ability examination in 2018 and 2019, respectively. In 2018, a total of 308 residents from 20 departments of the SAHZU took the STRP assessment. In 2019, a total of 326 residents from 22 departments of the SAHZU underwent the PDCA plan and took the STRP assessment. Compared with the results in 2018, the average FPR in the Zhejiang Province increased by 2.92% from 87.87 to 90.79% (
< 0.001). The FPR of the SAHZU increased by 7.88% from 85.06 to 92.94% (
= 0.001). In the SAHZU, the FPRs of the Department of Emergency and Department of Anesthesiology improved 34.51% (
= 0.024) and 20.36% (
= 0.004), respectively. There were no significant differences between the performances in the 2 years of the other 20 departments. There were improved results in the "Clinical Thinking and Decision-Making" and "Operation of Basic Skills" assessment stations with increases of 3.01% (
= 0.002) and 3.94% (
= 0.002), respectively. No statistically significant differences in the FPRs of the other six stations were found. The performances in all the stations in the final tests were better than in the stimulation tests (
< 0.001).
Although our sample size was relatively small, our results showed a small success of the PDCA plan in improving the quality of the STRP, especially for the residents in the Departments of Emergency and Anesthesiology. The PDCA plan also contributed to enhancing residents' abilities in the "Clinical Thinking and Decision-Making" and "Operation of Basic Skills" stations. Taken together, the PDCA plan may provide a practical framework for developing future training plans.
Intraoperative blood salvage, an effective blood conservation strategy, has not been applied in onco-surgery, because of potential malignant cell contamination. In this study we tested effectiveness ...of a modified leukocyte depletion filter (M-LDF) for removal of tumor cells.
The effects of M-LDF and regular LDF on removal of cells (HepG2 cell line) were compared. The safety of M-LDF was tested with blood (collected and washed during onco-surgery), the salvaged blood mixed with tumor cells from the solid tumor of the same patient, or mixed with HepG2 cells (n=30 in each protocol). Cancer cells were identified by flow cytometry, culture and bioassay with and without filtration.
M-LDF removed 5-log of HepG2 and nucleated cells, which was much higher than regular LDF, and cells were destroyed when they passed through M-LDF. Cytokeratin-positive cells in all samples were removed by M-LDF. Invasive growth adherent cells were found in most of unfiltered samples and 67% of the inoculated nude mice developed tumors in LDF-treated sample. Neither adherent cells nor nude mice developed tumors were found in M-LDF-treated samples.
Since M-LDF can effectively remove and destroy cancer cells in the salvaged blood, it has great potential for clinical application.
Background The Black-necked Crane (Grus nigricollis) is an internationally threatened crane living on the plateau, mainly in winter, in the Yarlung Tsangpo River basin in Tibet, western China. In the ...past five years, some economic development projects have been conducted in this area, posing potential threats to the wintering populations of the cranes and their habitats. Therefore, the current population dynamics of wintering Black-necked Cranes and habitat suitability in the Yarlung Tsangpo River basin were investigated. Methods Twenty counties were surveyed using the line transect method in December 2017 and January 2018, and we recorded the location, flock size, number of individuals, habitat types and presence of human disturbance in which they occurred. We compared the results from the middle wintering period in this survey with those from 2014. Results The highest number of cranes recorded was 8291, and the results showed that the cranes were mainly distributed in Lhaze, Namling, Samzhubze, and Lhunzub. A total of 577 and 495 flocks were recorded in the early and middle wintering periods, respectively. In the early wintering period, there were significant differences in the number of individuals across the different habitats, with crop stubble land and plowed land representing more than 30% of the total habitat utilization. In the middle wintering period, there were also significant differences in the number of individuals, and the utilization of crop stubble land represented over 60% of the total. Conclusions Wintering Black-necked Cranes mainly fed on spilled grains in stubble habitat after harvest. In the middle wintering period, some of the farmlands were plowed and irrigated, which resulted in food shortages in these areas, and the cranes tended to gather in mixed flocks of large size instead of as a single family. There were still considerable regional wintering populations decreases in Quxu, Nedong, and Sakya in 2018 compared with 2014, and these decreases were mainly due to some recently emerging threats, including farmlands being converted into areas of greenhouse cultivation, highway and railway construction, river dredging, the rapid development of the manufacturing and mining industries, and the lack of protection of important wintering sites. Keywords: Black-necked Crane, Habitat use, Population dynamics, Tibet, Yarlung Tsangpo River basin