OBJECTIVETo explore the effects of microtubule depolymerization (MD) on the spontaneous beating rate, action potential (AP), and oxygen consumption of cardiac myocytes in rats and its mechanism.

METHODSOne-hundred and eighty neonatal SD rats divided into 12 batches were used in the experiment, and 15 rats in each batch were sacrificed for the isolation and culture of cardiac myocytes after the heart tissues were harvested. The cardiac myocytes were respectively inoculated in one 12-well plate filled with 6 round cover slips, one 12-well plate filled with 6 square cover slips, two cell culture flasks, and two cell culture dishes. After routine culture for three days, the cardiac myocytes from all the containers were divided into normal control group (NC, routinely cultured with 3 mL DMEM/F12 solution rewarmed at 37 °C for 3 h) and group MD (routinely cultured with 3 mL DMEM/F12 solution rewarmed at 37 ° and containing 8 µmol/L colchicine for 3 h) according to the random number table, with 3 holes, 1 flask, or 1 dish in each group. The morphological changes in microtubules were observed with confocal laser scanning microscope after immunofluorescent staining. The content of polymerized or dissociative α-tubulin was determined by Western blotting. Spontaneous beating rate of the cells was observed and calculated under inverted microscope. Dissolved oxygen concentration of DMEM/F12 solution containing cardiac myocytes was determined by oxygen microelectrode system before and after the addition of colchicine. Additionally, dissolved oxygen concentration of DMEM/F12 solution and colchicine + DMEM/F12 solution was determined. The whole-cell patch-clamp technique was used to record AP, delayed rectifier K+ current (I(K)), and L-type Ca2+ current (I(Ca-L)) in cardiac myocytes; current density-voltage (I-V) curves were drawn based on the traces. Data were processed with independent or paired samples t-test.

RESULTS(1) In group NC, microtubules of cardiac myocytes were around the nucleus in radial distribution with intact and clear linear tubiform structure. The microtubules in group MD were observed in dispersive distribution with damaged structure and rough linear tubiform structure. (2) In group MD, the content of dissociative α-tubulin of cells (0.61 ± 0.03) was obviously higher than that in group NC (0.46 ± 0.03, t = -6.99, P < 0.05), while the content of polymerized α-tubulin (0.57 ± 0.04) was significantly lower than that in group NC (0.88 ± 0.04, t = 9.09, P < 0.05). (3) Spontaneous beating rate of cells was (59 ± 8) times per min in group MD, which was distinctly higher than that in group NC [(41 ± 7) times per min, t = 5.62, P < 0.01]. (4) Dissolved oxygen concentration of DMEM/F12 solution containing cardiac myocytes was (138.4 ± 2.5) µmol/L, and it was reduced to (121.7 ± 3.6) µmol/L after the addition of colchicine ( t = 26.31, P < 0.05). There was no obvious difference in dissolved oxygen concentration between DMEM/F12 solution and colchicine + DMEM/F12 solution (t = 0.72, P > 0.05). (5) Compared with that of group NC, AP morphology of cells in group MD changed significantly, with unobvious repolarization plateau phase and shorter action potential duration (APD). The APD20, APD50, and APD90 were respectively (36.2 ± 3.8), (73.7 ± 5.7), and (115.1 ± 8.0) ms in group MD, which were significantly shorter than those of group NC [(40.2 ± 2.3), (121.4 ± 7.0), and (169.4 ± 5.6) ms, with t values respectively 2.61, 15.88, and 16.75, P values below 0.05]. (6) Compared with that of group NC, the I-V curve of I(K) of cells in group MD moved up with higher current density under each test voltage (0 to 40 mV) after activation ( with t values from 2. 70 to 3. 76, P values below 0.05) . (7) There was not much alteration in current density of I(Ca-L) under each test voltage (-30 to 50 mV) between 2 groups (with t values from -1.57 to 1.66, P values above 0.05), and their I-V curves were nearly overlapped.

CONCLUSIONSAfter MD, the I(K) is enhanced without obvious change in I(Ca-L), making AP repolarization faster and APD shortened. Then the rapid spontaneous beating rate increases oxygen consumption of cardiac myocytes of rats.

Action Potentials ; Animals ; Cells, Cultured ; Energy Metabolism ; Microtubules ; metabolism ; Mitochondria, Heart ; metabolism ; Myocytes, Cardiac ; metabolism ; Rats ; Rats, Sprague-Dawley ; Tubulin ; metabolism

Objective To investigate the effects of propofol on the changes in myocardial Toll-like receptor 4 (TLR-4)and TNF-αand NF-κb protein expressions in ischemia-reperfusion injury (I/R).Methods Thirty healthy male SD rats weighing 250-320 g were randomly divided into 3 groups (n=10 for each):Group A,sham operation;Group B,I/R;and Group C,propofol + I/R.In Groups B and C myocardial I/R was induced by occlusion of the left anterior descending artery (LAD)for 30 min,followed by 120 min reperfusion.In Group C propofol was given intravenously 1 0 min before myocardial ischemia,followed by continuous infusion of propofol at 5 mg/(kg·h)until the end of 120 min reperfusion.In Groups A and B normal saline instead of propofol was given. The myocardial tissues were taken at the end of 120 min;ultrastructural changes of myocardial cells were observed under X-ray electron microscope and the expressions of TLR-4 mRNA as well as TNF-αand NF-κb protein were determined.Results Ultrastructural observation under electron microscope showed significantly worsened damage in myocardial tissue structure and mitochondria in Groups B and C compared with Group A.The myocardial expressions of TLR-4 and TNF-αand NF-κb protein were significantly higher in Groups B and C than in control Group A.The myocardial expressions of TLR-4 and TNF-αand NF-κb protein were down-regulated in Group C compared with Group B.Conclusion Intravenous injection of propofol can protect against myocardial damage.Propofol can suppress the increase in myocardial TLR-4 and TNF-αand NF-κb protein expressions induced by I/R.

Objective To evaluate the effect of carbon fiber couch on dose distribution of radiotherapy planning and verification pass rate.Methods Establishing the carbon fiber treatment couch model in Pinnacle8.0m Treatment Planning system (TPS),and then this model was used to correct dose calculations of oblique fields in the treatment plans of 10 cases of nasopharyngeal carcinoma,10 cases of breast cancer and 10 cases of lung cancer and evaluate the effect of carbon fiber couch on the whole dose distribution of the plans.Then these plans were measured by three-dimensional dose verification equipment Delta4 to confirm the improvement extent of Gamma pass rate after considering the carbon fiber treatment couch.Results For the majority of plans,when the carbon fiber couch was taken into consideration,the target doses was significantly reduced (4772 cGy-7266 cGy vs.4859 cGy-7347 cGy,P=0.000-0.002) and the relative deviation of D95 was 1％ to 3％.Measurement results of Delta4 showed that Gamma pass rate (3 mm/3％ criteria) increased in all plans (96.4％-98.8％ vs.93.4％-97.3％,P =0.000),some of that were up to 5 percentage when the couch model was applied.Conclusions Target doses will be overestimated if the treatment couch is ignored in TPS measurement.,However it should arouse enough attention when the disease with smaller doses corresponding gradient.

This study examined the effect of intensive insulin therapy on immune function and inflammatory factors at the early phase after severe trauma. At day 1, 3, 5, 7 after admission, subsets of CD4(+) helper T lymphocytes (Th1/Th2) and human leukocyte antigen (HLA)-DR expression on CD14(+) monocytes were flow cytometrically measured. Levels of cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10) and other immunity markers, such as IgA, IgG, IgM, C3, C4 and C reaction protein (CRP) were examined in two groups. The results showed that TNF-α, IL-6 and CRP levels in the intensive insulin therapy group were significantly lower than those in the conventional therapy group, whereas IL-10 levels were substantially increased after intensive insulin therapy. C3 level at day 3, 5, 7 and C4 levels at day 5, 7 were lower in the intensive therapy group than in the conventional therapy group. Th1/Th2 ratios decreased gradually over time in both groups, and were much lower at day 3, 5, 7 in intensive therapy group. There were significant differences among day 3 to day 7 after admission in HLA-DR expression in CD14(+) monocytes. It was concluded that the intensive insulin therapy could decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in the elderly suffering from severe trauma, at the same time, with complement recovery being delayed. Moreover, intensive insulin therapy promoted immune suppression and, therefore, measures need be taken to address the issue.

Objective:To study the effectiveness and safety of combined intraoral and cutaneous using of long pulsed 1064 nm Nd∶YAG and 2940 nm Er∶YAG lasers in facial rejuvenation.Methods:Twenty-one female patients with different grades of nasolabial fold were treated with 6 sessions of the combination lasers therapy once a month. Standardized photographs of VISIA were taken before and after treatment to record any changes of facial contour and nasolabial folds. The efficacy assessment was judged by two non-group experienced dermatologists using modified Fitzpatrick Wrinkle Scale (MFWS), based on the VISIA photos at base line, twelve-week and six-month after treatment. Self-scoring of 5-level satisfaction from patients was also collected and analyzed. Any side effects and complications were recorded.Results:At 12 weeks, mild and moderate nasolabial folds were improved notably, the mean value of MFWS decreased from 1.59 to 0.90, whereas severe nasolabial folds had no remarkable improvement. Six-month after treatment, 18 patients had notable improved, among them: five out of 7 mild cases, 9 out of 10 moderate cases and 2 out of 4 severe cases, and the mean value of MFWS significantly decreased to 0.57 ( P<0.001). The general satisfactory rate of self-scoring was 86%. Two patients had tolerable light burning pain during treatment and two patients got temporary pigmentation that vanished in three months. There were no other adverse reactions and complications. Conclusion:Combined intraoral and cutaneous using oflong pulse 1064 nm Nd∶YAG laser and 2940 nm Er∶YAG laser is a safe and effective therapy for facial rejuvenation.

This study examined the effect of intensive insulin therapy on immune function and inflammatory factors at the early phase after severe trauma. At day 1, 3, 5, 7 after admission, subsets of CD4(+) helper T lymphocytes (Th1/Th2) and human leukocyte antigen (HLA)-DR expression on CD14(+) monocytes were flow cytometrically measured. Levels of cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10) and other immunity markers, such as IgA, IgG, IgM, C3, C4 and C reaction protein (CRP) were examined in two groups. The results showed that TNF-α, IL-6 and CRP levels in the intensive insulin therapy group were significantly lower than those in the conventional therapy group, whereas IL-10 levels were substantially increased after intensive insulin therapy. C3 level at day 3, 5, 7 and C4 levels at day 5, 7 were lower in the intensive therapy group than in the conventional therapy group. Th1/Th2 ratios decreased gradually over time in both groups, and were much lower at day 3, 5, 7 in intensive therapy group. There were significant differences among day 3 to day 7 after admission in HLA-DR expression in CD14(+) monocytes. It was concluded that the intensive insulin therapy could decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in the elderly suffering from severe trauma, at the same time, with complement recovery being delayed. Moreover, intensive insulin therapy promoted immune suppression and, therefore, measures need be taken to address the issue.
Aged ; Aged, 80 and over ; Cytokines ; immunology ; Female ; Humans ; Hyperglycemia ; drug therapy ; immunology ; Hypoglycemic Agents ; therapeutic use ; Immunity, Innate ; drug effects ; immunology ; Immunologic Factors ; immunology ; Insulin ; therapeutic use ; Male ; Treatment Outcome ; Wounds and Injuries ; drug therapy ; immunology

Objective:To investigate the application of magnetic resonance imaging (MRI) in clinical staging and classification of adult Japanese encephalitis.Methods:The clinical data and craniocerebral MRI findings of 35 adult patients with Japanese encephalitis admitted in General Hospital of Ningxia Medical University from August to September 2018 were analyzed retrospectively. The MRI imaging characteristics were compared among patients with different stages and types, the apparent diffusion coefficient (ADC value) of thalamic lesions in patients of different stages was analyzed. SPSS 23.0 software was used to analyze the data.Results:Six moderate cases all had lesions involving the thalamus, and the number of intracranial lesions was <2. In 11 severe cases, 8 had lesions involving thalamus and 5 had lesions involving hippocampus; the number of intracranial lesions was <2 in 3 cases, the number of intracranial lesions was 2-4 in 3 cases, and the number of intracranial lesions was >4 in 5 cases. In 18 cases critical cases, the lesions involved thalamic in 14 cases, hippocampus in 14 cases, cerebral cortex in 14 cases, cerebral feet in 9 cases, basal ganglia area in 6 cases, and brain stem in 2 cases, respectively; 2 cases had the intracranial lesions <2, 6 cases had intracranial lesions 2-4, 10 cases had intracranial lesions >4. In 11 preliminary stage patients, 9 cases had DWI high signal and 2 had FLAIR slightly high signal; in 19 extreme stage patients, 16 cases had DWI high signal, 11 cases had FLAIR slightly high signal, 3 cases had T1WI high signal and 6 cases had T2WI high signal. In 5 recovery stage patients, 1 case had DWI slightly high signal, 5 cases had FLAIR high signal, and 1 case had T2WI high signal. The ADC values of thalamic lesions in recovery and extreme patients were higher than those in the preliminary stage ( q=3.931 and 4.012, P<0.05). The ADC value of thalamic lesions in the recovery period was higher than that in the extreme period ( q=3.372, P<0.05). Conclusions:The number of lesions and the range of involvement are associated with disease severity in adult Japanese encephalitis. The DWI sequence is easy to detect at early stage, and the FLAIR sequence shows a long time span of lesions; and the DWI and FLAIR sequences are of great significance for the early clinical staging and classification of adult encephalitis patients. At the same time, the ADC value shows a trend of disease progresses, which can be used as a supplement for the clinical staging in adult encephalitis patients.

Objective:To investigate the current status of endoscopic treatment for gastroesophageal varices in portal hypertension in China, and to provide supporting data and reference for the development of endoscopic treatment.Methods:In this study, initiated by the Liver Health Consortium in China (CHESS), a questionnaire was designed and distributed online to investigate the basic condition of endoscopic treatment for gastroesophageal varices in portal hypertension in 2022 in China. Questions included annual number and indication of endoscopic procedures, adherence to guideline for preventing esophagogastric variceal bleeding (EGVB), management and timing of emergent EGVB, management of gastric and isolated varices, and improvement of endoscopic treatment. Proportions of hospitals concerning therapeutic choices to all participant hospitals were calculated. Guideline adherence between secondary and tertiary hospitals were compared by using Chi-square test.Results:A total of 836 hospitals from 31 provinces (anotomous regions and municipalities) participated in the survey. According to the survey, the control of acute EGVB (49.3%, 412/836) and the prevention of recurrent bleeding (38.3%, 320/836) were major indications of endoscopic treatment. For primary [non-selective β-blocker (NSBB) or endoscopic therapies] and secondary prophylaxis (NSBB and endoscopic therapies) of EGVB, adherence to domestic guideline was 72.5% (606/836) and 39.2% (328/836), respectively. There were significant differences in the adherence between secondary and tertiary hospitals in primary prophylaxis of EGVB [71.0% (495/697) VS 79.9% (111/139), χ2=4.11, P=0.033] and secondary prophylaxis of EGVB [41.6% (290/697) VS 27.3% (38/139), χ2=9.31, P=0.002]. A total of 78.2% (654/836) hospitals preferred endoscopic therapies treating acute EGVB, and endoscopic therapy was more likely to be the first choice for treating acute EGVB in tertiary hospitals (82.6%, 576/697) than secondary hospitals [56.1% (78/139), χ2=46.33, P<0.001]. The optimal timing was usually within 12 hours (48.5%, 317/654) and 12-24 hours (36.9%, 241/654) after the bleeding. Regarding the management of gastroesophageal varices type 2 and isolated gastric varices type 1, most hospitals used cyanoacrylate injection in combination with sclerotherapy [48.2% (403/836) and 29.9% (250/836), respectively], but substantial proportions of hospitals preferred clip-assisted therapies [12.4% (104/836) and 26.4% (221/836), respectively]. Improving the skills of endoscopic doctors (84.2%, 704/836), and enhancing the precision of pre-procedure evaluation and quality of multidisciplinary team (78.9%, 660/836) were considered urgent needs in the development of endoscopic treatment. Conclusion:A variety of endoscopic treatments for gastroesophageal varices in portal hypertension are implemented nationwide. Participant hospitals are active to perform emergent endoscopy for acute EGVB, but are inadequate in following recommendations regarding primary and secondary prophylaxis of EGVB. Moreover, the selection of endoscopic procedures for gastric varices differs greatly among hospitals.