Objective To investigate the incidence and types of patient-ventilator asynchrony(PVA)in mechanically ventilated patients within the intensive care unit(ICU),and to identify associated high-risk factors,thereby providing a basis for reducing PVA,enhancing mechanical ventilation efficiency,and refining ventilation strategies.Methods A prospective observational study was conducted among patients admitted to the general ICU of the Affiliated Hospital of Guizhou Medical University from October to December 2024 who were receiving mechanical ventilation.Inclusion criteria were as follows:age ≥18 years and mechanical ventilation duration ≥12 hours.Exclusion criteria included complete controlled mechanical ventilation,palliative care or do-not-resuscitate status,and lack of informed consent.Senior respiratory therapists performed daily bedside observations of ventilator waveforms for 10～15 minutes between 08:00 and 12:00.PVA was diagnosed based on pressure-time and flow-time waveforms,with the types of PVA being recorded.Demographic and clinical data,including age,sex,body mass index(BMI),primary diagnosis,comorbidities,APACHEⅡ score at ICU admission,blood gas analysis,ventila-tion mode and parameters,analgesia and sedation status,duration of mechanical ventilation,and length of ICU stay,were collected.The incidence and types of PVA during the observation period were analyzed.Univariate and multivariate logistic regression analyses were performed to identify high-risk factors for PVA.Clinical outcomes were compared between patients with and without PVA.Results A total of 105 patients and 453 episodes of assisted mechanical ventilation waveforms were analyzed.Among these,60.95％(64/105)experienced at least one episode of PVA.Of the 453 ventilation waveforms assessed,35.76％(162/453)demonstrated PVA.The types of PVA,ranked by incidence,were as follows:cycling mismatch(12.58％,57/453),double triggering(11.92％,54/453),ineffective triggering(9.49％,43/453),flow starvation(5.30％,24/453),and exhalation flow limitation(1.77％,8/453).The incidence of PVA varied significantly across different ventilation modes:45.7％in volume-assist/control ventilation(V-A/C),38.1％in pressure-assist/control ventilation(P-A/C),42.9％in synchronized intermittent mandatory ventilation(SIMV),and 16.7％in pressure support ventilation(PSV)(P<0.001).Multi-variate logistic regression analysis revealed that the mechanical ventilation mode[reference:PSV;V-A/C:OR=4.687,95％CI:2.140～10.263,P<0.001;P-A/C:OR=2.922,95％CI:1.489～5.734,P=0.002;SIMV:OR=4.682,95％CI:1.758～12.466,P=0.002]and actual respiratory rate(OR=1.07,95％CI:1.016～1.127,P=0.011)were significant high-risk factors for PVA.Patients with PVA had a significantly longer duration of mechanical ventilation[8.21(5.35,13.91)days vs.3.00(1.96,5.71)days,P<0.001]compared to those without PVA.Conclusions PVA is commonly observed in ICU patients receiving assisted invasive mechanical ventilation,with cycling mismatch,double triggering,and ineffective triggering being the most prevalent types.The incidence of PVA tends to be lower when using the PSV mode.Clinically,real-time monitoring of patient-ventilator synchrony via ventilator waveforms,along with the optimization of ventilator modes and parameters,should be employed to minimize the occurrence of PVA and enhance the efficiency of mechanical ventilation.

Objective To investigate the incidence and types of patient-ventilator asynchrony(PVA)in mechanically ventilated patients within the intensive care unit(ICU),and to identify associated high-risk factors,thereby providing a basis for reducing PVA,enhancing mechanical ventilation efficiency,and refining ventilation strategies.Methods A prospective observational study was conducted among patients admitted to the general ICU of the Affiliated Hospital of Guizhou Medical University from October to December 2024 who were receiving mechanical ventilation.Inclusion criteria were as follows:age ≥18 years and mechanical ventilation duration ≥12 hours.Exclusion criteria included complete controlled mechanical ventilation,palliative care or do-not-resuscitate status,and lack of informed consent.Senior respiratory therapists performed daily bedside observations of ventilator waveforms for 10～15 minutes between 08:00 and 12:00.PVA was diagnosed based on pressure-time and flow-time waveforms,with the types of PVA being recorded.Demographic and clinical data,including age,sex,body mass index(BMI),primary diagnosis,comorbidities,APACHEⅡ score at ICU admission,blood gas analysis,ventila-tion mode and parameters,analgesia and sedation status,duration of mechanical ventilation,and length of ICU stay,were collected.The incidence and types of PVA during the observation period were analyzed.Univariate and multivariate logistic regression analyses were performed to identify high-risk factors for PVA.Clinical outcomes were compared between patients with and without PVA.Results A total of 105 patients and 453 episodes of assisted mechanical ventilation waveforms were analyzed.Among these,60.95％(64/105)experienced at least one episode of PVA.Of the 453 ventilation waveforms assessed,35.76％(162/453)demonstrated PVA.The types of PVA,ranked by incidence,were as follows:cycling mismatch(12.58％,57/453),double triggering(11.92％,54/453),ineffective triggering(9.49％,43/453),flow starvation(5.30％,24/453),and exhalation flow limitation(1.77％,8/453).The incidence of PVA varied significantly across different ventilation modes:45.7％in volume-assist/control ventilation(V-A/C),38.1％in pressure-assist/control ventilation(P-A/C),42.9％in synchronized intermittent mandatory ventilation(SIMV),and 16.7％in pressure support ventilation(PSV)(P<0.001).Multi-variate logistic regression analysis revealed that the mechanical ventilation mode[reference:PSV;V-A/C:OR=4.687,95％CI:2.140～10.263,P<0.001;P-A/C:OR=2.922,95％CI:1.489～5.734,P=0.002;SIMV:OR=4.682,95％CI:1.758～12.466,P=0.002]and actual respiratory rate(OR=1.07,95％CI:1.016～1.127,P=0.011)were significant high-risk factors for PVA.Patients with PVA had a significantly longer duration of mechanical ventilation[8.21(5.35,13.91)days vs.3.00(1.96,5.71)days,P<0.001]compared to those without PVA.Conclusions PVA is commonly observed in ICU patients receiving assisted invasive mechanical ventilation,with cycling mismatch,double triggering,and ineffective triggering being the most prevalent types.The incidence of PVA tends to be lower when using the PSV mode.Clinically,real-time monitoring of patient-ventilator synchrony via ventilator waveforms,along with the optimization of ventilator modes and parameters,should be employed to minimize the occurrence of PVA and enhance the efficiency of mechanical ventilation.

AIM:To explore the role of miR-195-5p in mediating trastuzumab resistance in gastric cancer and to validate its potential as a therapeutic target along with its target gene GPRC5A.METH-ODS:Trastuzumab-resistant gastric cancer cell lines(NCI-N87 and MKN45)were established.Cell viabili-ty under trastuzumab treatment was assessed us-ing CCK-8 assays.Expression levels of miR-195-5p were determined by RT-qPCR.Transfection with miR-195-5p mimics was performed to evaluate changes in trastuzumab sensitivity and prolifera-tion.GPRC5A expression was also measured by RT-qPCR,and the targeting relationship between miR-195-5p and GPRC5A was confirmed using a dual-lu-ciferase reporter assay.RESULTS:Parental cells showed higher sensitivity to trastuzumab than re-sistant cells,with miR-195-5p expression signifi-cantly lower in the latter.Overexpression of miR-195-5p in resistant cells enhanced trastuzumab sen-sitivity and reduced proliferation.GPRC5A was found to be upregulated in resistant cells,and miR-195-5p directly targeted GPRC5A,affecting cell pro-liferation under trastuzumab treatment.CONCLU-SION:miR-195-5p may regulate trastuzumab sensi-tivity in gastric cancer by targeting GPRC5A,sug-gesting potential as a molecular marker for trastu-zumab therapy guidance.

Oligodendrocytes(OLs)play a crucial role in the central nervous system,and the myelin sheath formed by them is essential for maintaining the normal function of the nervous system.Damage to the myelin sheath can trigger various nervous system diseases,which seriously affect the quality of life of patients.Clemastine,a traditional antihistamine,has shown certain potential in"repurposing old drugs"in recent years and can promote the repair of myelin sheath.This article summarizes the role of clemastine in regulating the differentiation,maturation,senescence,and apoptosis of OLs at multiple levels by acting on receptors on the OL membrane and regulat-ing the key signaling pathways in cells and epigenetic modifications in the nucleus.A deeper understanding of the mechanism of action of clemastine in OLs can help to provide new targets and new approaches for drug treatment of myelin-degenerative diseases.

AIM:To explore the role of miR-195-5p in mediating trastuzumab resistance in gastric cancer and to validate its potential as a therapeutic target along with its target gene GPRC5A.METH-ODS:Trastuzumab-resistant gastric cancer cell lines(NCI-N87 and MKN45)were established.Cell viabili-ty under trastuzumab treatment was assessed us-ing CCK-8 assays.Expression levels of miR-195-5p were determined by RT-qPCR.Transfection with miR-195-5p mimics was performed to evaluate changes in trastuzumab sensitivity and prolifera-tion.GPRC5A expression was also measured by RT-qPCR,and the targeting relationship between miR-195-5p and GPRC5A was confirmed using a dual-lu-ciferase reporter assay.RESULTS:Parental cells showed higher sensitivity to trastuzumab than re-sistant cells,with miR-195-5p expression signifi-cantly lower in the latter.Overexpression of miR-195-5p in resistant cells enhanced trastuzumab sen-sitivity and reduced proliferation.GPRC5A was found to be upregulated in resistant cells,and miR-195-5p directly targeted GPRC5A,affecting cell pro-liferation under trastuzumab treatment.CONCLU-SION:miR-195-5p may regulate trastuzumab sensi-tivity in gastric cancer by targeting GPRC5A,sug-gesting potential as a molecular marker for trastu-zumab therapy guidance.

Objective To explore the feasibility and safety of MCCE in gastrointestinal examination of elderly patients with malignant tumors.Methods Clinical data of 127 patients who underwent MCCE examination from April 2019 to September 2022 were retrospectively analyzed.According to age,the patients were divided into the elderly group(age≥65 year-old,n = 88)and the middle-aged group(40≤age<65 year-old,n = 39),and the clinical data of patients with malignant tumors were screened from the two groups for analysis and comparison.Results 131 patients received MCCE examination,and 4 elderly patients were excluded from this study due to swallowing failure,so 88 elderly patients were actually included in the study.In the elderly group,45.4%had serious cardiovascular diseases(40/88),27.3%had malignant tumors(24/88),8.0%had serious respiratory diseases(7/88),6.8%had anesthesia problems(6/88),and 9.1%had neurological diseases(8/88).Among the 24 elderly patients with malignant tumors,25.0%had severe cardiovascular disease,25.0%had poor general status,20.8%had brain metastases,and 12.5%had severe respiratory dysfunction.The positive diagnosis rate of gastric P2 lesions in the elderly group(52/88,59.1%)was significantly higher than that in the middle-aged group(13/39,33.3%)(P = 0.013).There was significant difference in positive rate of ulcer diagnosis between the two groups(29.5%and 10.2%)(P = 0.032).In patients with malignant tumors,the positive rate of ulcer diagnosis between the two groups(45.8%and 11.1%)was statistically significant(P = 0.038).The cleanliness and visualization scores of proximal stomach in the middle-aged group were higher than those in the elderly group,and the differences were statistically significant(P<0.05).Conclusion MCCE is generally effective and safe in elderly patients,especially those with malignant tumors,without missing any significant gastric lesions.

Objective:To discuss the feasibility of offering specialized courses of critical care medicine in undergraduate clinical medicine education, so as to alleviate the shortage of critical care medicine staffs and lay a foundation for improving the success rate for the treatment of critical cases.Methods:The undergraduates majoring in clinical medicine from 2008 to 2011 in Guizhou Medical University (the former Guiyang Medical College) were enrolled. After they had been enrolled in the undergraduate education for 3 years and were ready for Grade four, which meant basic medicine teaching had been completed and clinical medicine teaching was about to start, they were introduced and preached to each discipline, including critical care medicine. The undergraduates were free to choose professional direction of clinical training in Grade four. Students majoring in clinical medicine from 2012 to 2014 were free to choose their major direction when they entered the school.Results:From September 2011 to July 2019, the university had cultivated 246 undergraduates majoring in clinical critical care medicine from 2008 to 2014, and the critical care medicine professional team of affiliated hospital had undertaken 540 teaching hours. By July 2019, all students had graduated on time, with an employment rate of 100%. Forty students took postgraduate programs in our school and other schools, accounting for 16.3%.Conclusions:Professional education of critical care medicine in the undergraduate course of clinical medicine can mobilize students' interest in learning and subjective initiative, which is conducive to career selection. During the clinical training, the students can identify and timely cure critical care cases in the early stage, and partly alleviate the current shortage of critical care medical staffs.

We employed a multiplex polymerase chain reaction (PCR) coupled with capillary electrophoresis (mPCR-CE) targeting six Clostridium difficile genes, including tpi, tcdA, tcdB, cdtA, cdtB, and a deletion in tcdC for simultaneous detection and characterization of toxigenic C. difficile directly from fecal specimens. The mPCR-CE had a limit of detection of 10 colony-forming units per reaction with no cross-reactions with other related bacterial genes. Clinical validation was performed on 354 consecutively collected stool specimens from patients with suspected C. difficile infection and 45 isolates. The results were compared with a reference standard combined with BD MAX Cdiff, real-time cell analysis assay (RTCA), and mPCR-CE. The toxigenic C. difficile species were detected in 36 isolates and 45 stool specimens by the mPCR-CE, which provided a positive rate of 20.3% (81/399). The mPCR-CE had a specificity of 97.2% and a sensitivity of 96.0%, which was higher than RTCA (x = 5.67, P = 0.017) but lower than BD MAX Cdiff (P = 0.245). Among the 45 strains, 44 (97.8%) were determined as nonribotype 027 by the mPCR-CE, which was fully agreed with PCR ribotyping. Even though ribotypes 017 (n = 8, 17.8%), 001 (n = 6, 13.3%), and 012 (n = 7, 15.6%) were predominant in this region, ribotype 027 was an important genotype monitored routinely. The mPCR-CE provided an alternative diagnosis tool for the simultaneous detection of toxigenic C. difficile in stool and potentially differentiated between RT027 and non-RT027.
Clostridium Infections ; diagnosis ; Clostridium difficile ; genetics ; Electrophoresis, Capillary ; Feces ; microbiology ; Genes, Bacterial ; Humans ; Polymerase Chain Reaction ; Ribotyping ; Sensitivity and Specificity

Objective To investigate the characteristics of target motion in esophageal cancer during normal breathing with four-dimensional computed tomography(4DCT). Methods Twenty patients with primary esophageal cancer received respiratory gated 4DCT to obtain the target motion during normal breathing and delineate the gross tumor volume (GTV). The center coordinate and volume of each GTV were measured and recorded to calculate the displacement of the GTV center and the change in volume in different respiratory phases. Results The displacement of the GTV center in each esophageal segment in superior-inferior direction (0.521±0.319 cm) was significantly greater than that in right-left direction (0.169± 0.083 cm) and that in anterior-posterior direction (0.167±0.095 cm)(all P<0.05). The maximum displacement of the GTV center in each direction was significantly different in different esophageal segments(all P<0.05).The displacement of the GTV center in each direction was not entirely consistent in different respiratory phases. The displacement of the GTV center in each direction in T50phase was greatest when T0phase was the reference phase. The volume of GTV had no significant changes at the end of the expiratory phase and the inspiratory phase (P=0.313). Conclusions The displacement of GTV center in each esophageal segment in superior-inferior direction is significantly greater than that in right-left direction and that in anterior-posterior direction and the displacement of GTV center in each direction is significantly different in different esophageal segments. Therefore, all the factors should be considered to develop a reasonable target for precise radiotherapy. For esophageal cancer in cervical and upper chest esophageal segment,it is reasonable to delineate ITV based on the fusion image of the images at the end of inspiratory phase and expiratory phase. The deformation of target volume of the esophageal cancer in the cervical and upper chest esophageal segment is not significant in the respiratory cycle.

Objective To investigate the effects of transient receptor potential cation channel 6 (TRPC6) on the expression of nephrin, desmin and caspase 9 and on the apoptosis of podocytes in a mouse model of podocyte injury induced by TGF-β1.Methods Conditionally immortalized mouse podocytes were cultured in vitro and divided into four groups: control, TGF-β1 treatment, TGF-β1+PGPU6/GFP/Neo-TRPC6-mus-581 (TRPC6 knockdown) and TGF-β1+PGPU6/GFP/Neo-NC (negative control).Real-time RT-PCR and Western blot analysis were performed to detect the expression of nephrin, desmin and caspase 9 at mRNA and protein levels, respectively.Flow cytometry was used to analyze the apoptotic rate of podocytes.DAPI fluorescent staining was used to observe the morphological changes of apoptotic podocytes.Results Green fluorescent protein (GFP)-expressing podocytes at 48 hours after transfection were significantly more than those at 24 hours after transfection.The level of TRPC6 in mouse podocytes transfected with PGPU6/GFP/Neo-TRPC6-mus-581 was significantly decreased as compared with that of the control group (P<0.05).No significant difference in the expression of TRPC6 was observed between the negative control group and the control group.Compared with the control group, the TGF-β1 treatment group showed increased expression of desmin and caspase 9 at both mRNA and protein levels (P<0.01), but decreased expression of nephrin at mRNA and protein levels at 48 hours after TGF-β1 intervention (P<0.05).The up-regulated desmin and caspase 9 and the down-regulated nephrin induced by TGF-β1 could be inhibited by the means of TRPC6 knockdown.The apoptosis rate of podocytes in TGF-β1 treatment group was (14.0±2.1)%, while that in TRPC6 knockdown was (10.90±0.56)% (P<0.05).The apoptosis rate of podocytes in negative control group was higher than that in TGF-β1 treatment group (P>0.05).More apoptotic cells with typical morphological features of apoptosis were observed after exposure to TGF-β1 for 48 hours.Conclusion TGF-β1 could induce the apoptosis of podocytes, inhibit the expression of nephrin and enhance the expression of caspase 9 and desmin, the possible mechanisms of which may be related to TRPC6 signal pathway.These changes in TGF-β1-treated podocytes could be alleviated by inhibiting the expression of TRPC6, which might have a protective effect on podocyte injury.