[Exosomes derived from miR-133a-3p engineered mesenchymal stem cells promote myocardial repair in rats after acute myocardial infarction].

Objective: To investigate the effects of exosome derived from miR-133a-3p engineered human umbilical cord blood mesenchymal stem cells (ucMSC) on myocardial repair after acute myocardial infarction (AMI) in rats. Methods: UcMSC was amplified and cultured in vitro. Lentiviral carrying miR-133a-3p and negative control vectors were transfected into ucMSC. Exosomes secreted by the transfected ucMSC were named miR-133a-3p-Exo and miR-NC-Exo, respectively. The AMI model of rats was established by ligation of the left anterior descending coronary artery. MiR-133a-3p-Exo or miR-NC-Exo were then injected into the border zone of the infarct area. Cardiac function was assessed by echocardiography after twenty-eight days of intervention, and Masson staining was used to evaluate the area of myocardial fibrosis post-AMI. The myocardial apoptosis after infarction was evaluated by TUNEL staining and the angiogenesis after infarction was evaluated by immunofluorescence staining in the current study. Results: Compared with the miR-NC-Exo group, the left ventricular ejection fraction in the miR-133a-3p-Exo group was significantly increased ((47.4%±9.8%) vs. (64.2%±8.9%), P<0.05). While the myocardial fibrosis area ((31.2%±7.3%) vs. (18.0%±1.5%), P<0.01) and the percentage of apoptotic cardiomyocytes ((25.6%±3.6%) vs. (15.1%±4.4%), P<0.05) was significantly reduced in the miR-133a-Exo group. Besides, the expression of CD31 and α-smooth muscle actin (α-SMA) were also increased significantly in the miR-133a-3p-Exo group compared to the miR-NC-Exo group (CD31: (2.9±0.9) vs. (13.9±2.0), P<0.000 1, α-SMA: (3.5±0.9) vs. (11.0±1.6), P<0.000 1). Conclusion: Exosome derived from miR-133a-3p engineered ucMSC effectively inhibited myocardial apoptosis and promoted angiogenesis, thus improving the cardiac function after myocardial infarction in rats.

Wheat-dependent exercise-induced anaphylaxis in Chinese people: a clinical research on 33 cases with antigenic analysis of wheat proteins.

BACKGROUND: Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a severe allergic condition in which wheat ingestion together followed by physical exercise induces anaphylaxis. For patients with WDEIA, omega-5 gliadin is considered to be one of the major allergens. AIM: To analyse the clinical features and allergen spectrum of WDEIA and to investigate the relationship between WDEIA and serum levels of platelet-activating factor (PAF), interleukin (IL)-9 and IL-33. METHODS: Medical histories and conditions of WDEIA cases were collected and summarized, with allergen tests of wheat proteins measured at the same visit. Of the 33 patients enrolled, 13 also had serum levels of PAF, IL-9 and IL-33 measured. The healthy control (HC) group consisted of 13 healthy individuals, who also underwent both the wheat-protein allergen tests and the inflammatory-mediator tests. RESULTS: All patients experienced severe allergic reaction during exercise after wheat ingestion. Manifestations of WDEIA included facial oedema, generalized urticaria and respiratory symptoms. Unconsciousness was also observed in 21 cases. In the patient group, 57.6% were confirmed as hypersensitive to glyceraldehyde-3-phosphate dehydrogenase (GAPDH), while 54.5% were allergic to omega-5 gliadin. PAF concentration was significantly higher in patients with WDEIA compared with HCs, whereas there was no significant difference in IL-9 or IL-33 between the two groups. CONCLUSIONS: WDEIA is a rare type of anaphylaxis. GAPDH and omega-5 gliadin may be the most common allergy-causing wheat proteins for Chinese people. PAF may be associated with the onset and development of WDEIA.

[Molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus during 2017-2018 at a hospital in Shanghai].

Objective: To identify the epidemic clones of MRSA isolates at a hospital in shanghai. Methods: A total of 72 MRSA isolates have been isolated from a second grade hospital between 2017 and 2018, including 32 CA-MRSA isolates, 13 HA-MRSA isolates and 26 MRSA isolates from environment. In this study, MLST and PFGE typing methods were used to analyze the molecular epidemiology of the MRSA isolates. Results: A total of 72 MRSA isolates have been obtained including 46 isolates from clinical specimens, 26 isolates from environments. The 46 MRSA isolates from clinical specimens consisted of 33 CA-MRSA (community-acquired MRSA) and 13 HA-MRSA (hospital-acquired MRSA). Furthermore, these patients infected with MRSA isolates were mostly distributed in the department of geriatrics (34.8%, 16/46), internal medicine (26.1%, 12/46) and surgery (26.1%, 12/46). MLST typing results showed that ST764 was predominant in isolates from both clinical specimens and hospital environments. Furthermore, PFGE typing results showed that most ST764 MRSA had high homolog (>90%). Conclusion: ST764 MRSA isolates might spread in community, hospital and environments. Therefore, continuous monitoring of MRSA and its variation may be useful in understanding the involvement of epidemic clone, and in searching new strategies to control MRSA infection.

[Safety and efficacy of regional transport combined with PCI model in patients with STEMI after thrombolysis in northwest China].

Objective: To investigate the safety and efficacy of regional transport to percutaneous coronary intervention(PCI) hospitals from non-PCI hospitals after thrombolysis in patients with acute ST-segment elevation myocardial infarction(STEMI) in northwest China. Methods: In this retrospective study, 1 062 STEMI patients who were transferred from non-PCI hospitals within 24 hours from symptom onset, during January 2015 and January 2019 in the First Hospital of Lanzhou University, were included. According to the treatment strategy, they were divided into two groups, namely intravenous thrombolysis combined with PCI group(n=240), and primary PCI group(n=822). Observation endpoint were in-hospital adverse cardiovascular and cerebrovascular events and bleeding events, Including all-cause death, ischemic stroke, malignant arrhythmia, intracranial hemorrhage and hemorrhage with hemoglobin decrease≥50 g/L. Results: A total of 1 062 STEMI patients were included(age was (61±12) years old), with 905 males (85.2%). The proportion of grade 0 TIMI blood flow in the primary PCI group before operation was significantly higher than that in the thrombolysis combined with PCI group(63.0%(518/822) vs. 36.3%(87/240)， P<0.001). Compared with primary PCI group, the time from symptom onset to first medical contact(2.11(1.00, 4.00)hours vs.3.00(1.13, 7.07)hours, P<0.001) and reperfusion in thrombolysis combined with PCI group(3.07(1.83, 4.87)hours vs. 6.92(4.07, 11.15) hours, P<0.001) were significantly shorter. The proportion of all-cause death was significantly higher in the primary PCI group than that in the thrombolysis combined with PCI group (1.8%(15/822) vs. 0, P=0.03). There was no significant difference in hemorrhage, ischemic stroke and malignant arrhythmia between the two groups(all P>0.05). Conclusions: For STEMI patients initially hospitalized in non-PCI hospitals, regional transport combined with PCI is feasible and effective. It does not significantly increase the risk of bleeding and cardiovascular and cerebrovascular events, with shorter time from symptom onset to myocardial reperfusion.

[Evaluation of neurovascular function in mouse cortex using multispectral optical imaging after ischemic stroke].

Objective: To acquire the signal of neuron excitability and blood oxygen in mouse cortex after ischemic stroke, and to clarify the relationship between the change of neurovascular function and the degree of cerebral infarction. Methods: The male C57BL/6 mouse(n=20) about 6-8 weeks and 20 g weight were produced the embolic stroke modal by photochemical injury. The mouse cortex was scanned by the multispectral optical imaging while using electric stimulation in 1, 3 and 7 d after operation. Then several data around the infarction were acquired including neuron excitability, the total hemoglobin concentration and deoxygenated hemoglobin concentration. The ischemic cerebral infarction size was analyzed by TTC staining. Plasma TNF-α concentration was measured by enzyme-linked immunosorbent assay(ELISA). And modified neurological severity score (mNSS) was recorded after ischemic stroke(n=30). Then correlativity analysis was used between the optical signals and three indicators of cerebral infarction degree. Results: The changes of neuron excitability signals were 1.15%±0.28%, 2.84%±1.06%, 2.21%±0.55%. The total hemoglobin concentration signals were 3.71%±2.76%,3.19%±2.70%,4.27%±3.05%. The deoxygenated hemoglobin concentration signals were 2.93%±2.33%, 3.60%±1.74%, 2.08%±1.28%. The neural signal was correlated to cerebral infarction size, plasma TNF-α concentration and mNSS(r=-0.441, -0.449,-0.404, all P<0.05), and mNSS had a great effect on neuron excitability(ß=-0.169,P<0.05). Meanwhile, the total hemoglobin concentration was correlated to cerebral infarction size(r=0.440,P<0.05). Conclusion: The signal of neuron and blood oxygen is able to represent the change of neurovascular function and evaluate the progression of ischemic stroke.

[Correlation between serum interleukin-38 and acute exacerbation of chronic obstructive pulmonary disease with pulmonary embolism].

Objective: To investigate the correlation between serum interleukin-38 (IL-38) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with pulmonary embolism (PE). Methods: The 94 patients with AECOPD admitted to Tianjin Chest Hospital from August 2015 to April 2018 were suspected of PE. They were divided into two groups based on CT pulmonary angiography (CTPA) and color Doppler ultrasound of lower extremity veins: 39 cases in PE group and 55 cases in Non-PE group. The general data and laboratory examination results of these subjects were recorded. Serum IL-38 was measured by double antibody enzyme-linked immunosorbent assays (ELISA). The between-group differences of above parameters were analyzed. Pearson correlation or Spearman rank correlation was used to analyze the association of IL-38 with each variable in AECOPD patients. Binary Logistic regressions were conducted to determine the risk factors of AECOPD with PE. ROC curve was used to assess the value of serum IL-38 in predicting AECOPD with PE. Results: The serum level of IL-38 was lower in PE group than in Non-PE group [46.3 (33.1, 58.1) vs 61.5 (46.6, 72.5) ng/L, P<0.05]. Correlation analysis showed that serum IL-38 levels were negatively correlated with C reactive protein and fibrinogen in patients with AECOPD (r=-0.38,-0.29, all P<0.05). Binary Logistic regressions showed that lower serum IL-38 level was a risk factor of AECOPD with PE (OR=0.78, 95%CI: 0.61-0.94, P<0.05). The area under the ROC curve was 0.74 (95% CI: 0.63-0.84, P<0.05). When cutoff value of serum IL-38 was 52.1ng/L, the sensitivity was 70.9% and the specificity was 69.2% respectively. Conclusion: IL-38 could relieve the hypercoagulability by inhibiting inflammation in patients with AECOPD and could act as a predictor of AECOPD with PE.

[Relationship between systolic blood pressure load and sleep stability in patients with essential hypertension].

Objective: To explore the relationship between blood pressure load and sleep stability in hypertensive patients by cardiopulmonary coupling monitoring (CPC) and 24-hour ambulatory blood pressure monitoring. Methods: One hundred and fifty-five patients with essential hypertension were divided into high load group and low load group according to whether the blood pressure load was higher than 50%. The relationship between sleep stability and systolic blood pressure load was analyzed by logistic regression. Results: After adjusting for sex, age and body mass index (BMI), logistic regression analysis showed that stable sleep was the protective factor (OR=0.736,P=0.047) for the decrease of nocturnal blood pressure load, and unstable sleep was the risk factor for increasing day time blood pressure load (OR=1.336, P=0.037) in patients with hypertension. Conclusions: The effect of sleep stability on blood pressure load is different between day and night. Stable sleep is the protective factor of nocturnal systolic blood pressure load decrease, and unstable sleep is the harmful factor of daytime systolic blood pressure load increase. Increasing sleep stability helps to reduce systolic blood pressure load.

Giant Magneto-Impedance (GMI) Effect in Single-Layer Soft Magnetic Film Under Stress.

The stress-induced magnetic anisotropy can significantly affect giant magneto-impedance (GMI) effect of the soft magnetic film. This paper is devoted to the GMI effect of the single layer soft magnetic film implied without and with a stress. By simulating a physical model with MATLAB and COMSOL software, the impedance expression of the single layer soft magnetic film and the relation between external magnetic field and magnetic permeability are deduced. We observed that, without a stress, the sensitive region increased firstly and then decreased with the increasing of the excitation current frequency from 1 MHz to 200 MHz. While the film was subjected to the stress in the direction of the current with one end stressed, the stress on the film was gradually reduced from stressed end to free end. Also, the impedance change rate of the film changed when the stress was added, which is similar to the effect of adding a bias magnetic field on the film. More importantly, the addition of stress σ can induce the bias of the GMI measurement range and improve its sensitivity near zero magnetic fields. This may provide a new way for designing a GMI sensor with higher sensitivity and adjustable measurement range.

[Interleukin-38 expression and clinical significance in serum of patients with chronic obstructive pulmonary disease].

Objective: To investigate the serum level of interleukin-38 (IL-38) and its clinical significance in patients with chronic obstructive pulmonary disease (COPD). Methods: Totally 72 patients with acute exacerbation of COPD (AECOPD group) and 65 patients with stable COPD (S-COPD group) were recruited from Tianjin Chest Hospital from June 2016 to August 2017. In the same period 40 elderly healthy subjects were selected as control group (C group). The general data and laboratory examination results of these subjects were recorded. Serum IL-38 was measured by double antibody enzyme-linked immunosorbent assays (ELISA). The inter-group differences of above parameters were analyzed. Pearson correlation or Spearman rank correlation analysis was used to analyze the correlation between IL-38 and each variable, and multivariate stepwise regression analysis was used to determine the influencing factors of serum IL-38 in COPD patients. Results: The serum level of IL-38 was higher in AECOPD group than in S-COPD group[(57.88±13.72) vs (51.75±14.06) ng/L, P<0.05], and was higher in either of the two COPD groups than in C group[(46.37±13.18) ng/L](both P<0.05). Correlation analysis of single factor showed that serum IL-38 levels were positively correlated with body mass index (r=0.190, P<0.05), and negatively correlated with C reactive protein (CRP), fibrinogen (FIB), forced expiratory volume in one second as a percentage of estimated value (FEV1%pred) and the number of acute exacerbations in the past 1 year (r=-0.344, -0.176, -0.195, -0.229, all P<0.05). The CRP level and the number of acute exacerbations in the past 1 year were independent factors affecting the serum level of IL-38 (ß=-0.204, -0.183, both P<0.05) in patients with COPD. Conclusion: IL-38 is compensatory increased in serum of patients with COPD and may be used as one of the serological markers for evaluation of COPD.

[The association between blood pressure variability and sleep stability in essential hypertensive patients with sleep disorder].

Objective: To investigate the association of blood pressure variability and sleep stability in essential hypertensive patients with sleep disorder by cardiopulmonary coupling. Methods: Performed according to strict inclusion and exclusion criteria, 88 new cases of essential hypertension who came from the international department and the cardiology department of china-japan friendship hospital were enrolled. Sleep stability and 24 h ambulatory blood pressure data were collected by the portable sleep monitor based on cardiopulmonary coupling technique and 24 h ambulatory blood pressure monitor. Analysis the correlation of blood pressure variability and sleep stability. Results: In the nighttime, systolic blood pressure standard deviation, systolic blood pressure variation coefficient, the ratio of the systolic blood pressure minimum to the maximum, diastolic blood pressure standard deviation, diastolic blood pressure variation coefficient were positively correlated with unstable sleep duration (r=0.185, 0.24, 0.237, 0.43, 0.276, P<0.05). Conclusions: Blood pressure variability is associated with sleep stability, especially at night, the longer the unstable sleep duration, the greater the variability in night blood pressure.

Dynamic contrast-enhanced magnetic resonance angiography for the localization of spinal dural arteriovenous fistulas at 3T.

OBJECTIVE: This study was undertaken to evaluate the accuracy of dynamic contrast-enhanced magnetic resonance angiography (DCE-MRA) in the precise location and demonstration of fistulous points in spinal dural arteriovenous fistulas (SDAVFs). METHODS: Fifteen patients (14 men, 1 woman; age range: 40-78 years; mean: 55.5 years) harboring SDAVF who underwent preoperative DCE-MRA and spinal digital subtraction angiography (DSA) between January 2012 and January 2015 were evaluated retrospectively. Two reviewers independently evaluated the level and side of the arteriovenous fistula and feeding artery on 3T DCE-MRA and DSA images. The accuracy of DCE-MRA was assessed by comparing its findings with those from DSA and surgery in each case. RESULTS: All 15 patients underwent DCE-MRA and DSA. DSA was unsuccessful in two patients due to technical difficulties. All cases were explored surgically, guided by the DCE-MRA. Surgery confirmed that 14 AVF sites were located in the thoracic spine, 5 in the lumbar spine, and 1 in the cervical spine. The origin of the fistulas and feeding arteries was accurately shown by DCE-MRA in 11 of the 15 patients. DCE-MRA also detected dilated perimedullary veins in all 15 patients. Overall, DCE-MRA facilitated DSA catheterization in 10 cases. In six patients, the artery of Adamkiewicz could be observed. In 15 out of 20 fistulas (75%), both readers agreed on the location on DCE-MRA images, and the κ coefficient of the interobserver agreement was 0.67 (95% confidence interval [CI], 0.16-0.87). In 13 of 16 shunts (75%), the DCE-MRA consensus findings and DSA findings coincided. The intermodality agreement was 0.77 (95% CI: 0.35-0.92). CONCLUSIONS: Our DCE-MRA studies benefited from the use of a high-field 3T MR imaging unit and reliably detected and localized the SDAVF and feeding arteries. As experience with this technique grows, it may be possible to replace DSA with DCE-MRA if surgery is the planned treatment.

[Correlation with MRI features, cell density and the expression of immunohistochemistry of pure mucinous breast carcinoma].

Objective: To explore the MRI features of the pure mucinous breast carcinoma(PMBC) and the correlation with cell density and the expression of immunohistochemistry. Methods: MRI features of 35 pure mucinous carcinomas were retrospectively analyzed from January 2011 to May 2016 in Guangdong General Hospital. MR images were reviewed for shape, margin, the signal intensity, enhancement patterns of tumors and diffusion weighted imaging (DWI) features and apparent diffusion coefficient (ADC) value. All the patients were detected by immunohistochemical staining with expression of ER, PR, CerbB-2, Ki-67 and Her-2. Correlations between MRI features of PMBC and cell density and the expression of immunohistochemistry were analyzed. Results: A total of 16 oval masses(16/35, 45.7%) and 10 round masses(10/35, 28.6%)were found in 35 PMBC with clear boundary(26/35, 74.3%) and lobulated shape(31/35, 88.6%). Very high signal intensity on T(2)-weighted images was found in 33 PMBC (33/35, 94.3%) and early enhancement rate was 115%±9% for PMBC. 28 PMBC demonstrated persistent enhancing pattern on time-signal intensity curve and 7 PMBC demonstrated plateau pattern.Mean ADC value was (1.91±0.06)×10(-3)mm(2)/s for PMBC. There was significant difference with early enhancement rate and ADC value between PMBC with more or less quantities of cellular mucin (P<0.05). There was no significant difference with ER, PR, CerbB-2, Her-2 and Ki-67 expression between PMBC with more or less quantities of cellular mucin (all P>0.05). Conclusions: PMBC has distinctive MRI features. The prognosis of PMBC is better from correlation between MRI features, cell density and the expression of immunohistochemistry.

Initial periodontal therapy for the treatment of gingival pregnancy tumor.

The purpose of this study was to evaluate the clinical efficacy of initial periodontal therapy in gingival pregnancy tumors. Thirty-nine patients diagnosed with gingival tumors of pregnancy between 2007 and 2015 were enrolled in this study. The patients received initial periodontal therapy, then supportive periodontal therapies at 3- to 6-month intervals. The patients underwent follow up for 6 months to 8 years after treatment. After plaque control, supragingival scaling, and root planning, the tumors in 25 patients were gradually eliminated without the necessity of surgery. In 3 patients, tumors <5 mm in size disappeared in a mean time of 3.6 months, 4 patients with tumors 5-10 mm disappeared in a time of 7.5 months, 11 patients with tumors 10-15 mm disappeared in 10.2 months, 6 patients with tumors 15-20 mm disappeared in 15 months, and one patient with a tumor >20 mm disappeared in 20 months. No recurrence of gingival pregnancy tumors was noted during subsequent follow-up. Initial periodontal therapy combined with oral hygiene maintenance is efficacious in treating gingival pregnancy tumors of patients with normal hormone levels, which can potentially serve as an option to avoid surgery.

Comparison of through-the-scope stent insertion with standard stent insertion for the management of malignant colorectal obstruction: a prospective study.

BACKGROUND: The aim of the present study was to compare the feasibility, safety and efficacy of the through-the-scope (TTS) stent technique to that of the standard metallic stent technique for the management of malignant colorectal obstruction. METHODS: Fifty-two patients scheduled to receive stent insertion for the management of acute obstructive colorectal cancer were enrolled in our study and divided into a TTS stent group (n = 24) and a standard stent group (n = 28). The stent insertion procedure was performed under endoscopic and fluoroscopic guidance in all patients. The success rate, complications, fluoroscopic time, and clinical remission rate were recorded and compared. RESULTS: The technique success rate was 100 % (24/24) in the TTS stent group and 78.6 % (22/28) in the standard stent group (p = 0.03). In five patients in the standard stent group, the stent failed to pass through occlusive lesions because of the stiffness of the stent system. Serious bleeding occurred in one patient in the standard stent group. The fluoroscopy time in the TTS stent group was significantly reduced (12.9 ± 6.6 min) compared with that of the standard stent group (24.8 ± 9.8 min; p < 0.01). Silent perforation occurred in 17.9 % (5/28) of the cases in the standard stent group compared with none in the TTS (p = 0.03). Clinical remission was achieved in 97.1 % (23/24) and 78.6 % (22/28) of patients in the TTS and standard stent groups, respectively (p = 0.11). CONCLUSIONS: The TTS stent is safer and more feasible for the management of malignant colorectal obstructions than the standard stent, and the TTS technique provides a higher success rate, a similar clinical remission rate, and a markedly reduced fluoroscopic time.

[Relationship between sleep architecture and blood pressure dynamic change in patients with sleep apnea syndrome].

OBJECTIVE: To investigate sleep architecture and blood pressure dynamic change in patients with Sleep apnea syndrome by electrocardiogram-based cardiopulmonary coupling analysis system. METHODS: Seventy-nine sleep disorder participants (PSQI≥8) were enrolled. Electrocardiogram-based cardiopulmonary coupling analysis device and ambulatory blood pressure monitoring were synchronously used to evaluate sleep architecture and blood pressure circadian rhythm. The patients were divided into SAS group (47 participants) and non-SAS group (32 participants) according to the Apnea Hypopnea Index (AHI) that calculated by CPC device. The data of sleep architecture and blood pressure variability were compared between two groups. RESULTS: Compared with non-SAS group, SAS group have less proportion of deep sleep, more proportion of light sleep, higher mean blood pressure in 24 hours and daytime, lower nocturnal blood pressure dipping, faster mean heart rate in night time (P<0.05). AHI has moderate inverse correlation with deep sleep time, wake/dream time (-0.6≤r<-0.3), moderate positive correlation with light sleep time (0.3

Confirmation of soybean plastid rRNAs by formaldehyde denaturing agarose gel electrophoresis.

Owing to their prokaryotic origin, plastid rRNAs are mainly 23s/16s/5s rRNAs. We present a novel plant RNA isolation method in this paper. Also, not only the eukaryotic 28s (26s, 25s)/18s rRNAs but the prokaryotic 26s/23s rRNAs as well were demonstrated in a single sample for the first time by formaldehyde denaturing agarose gel electrophoresis.

Association of dietary intake of folate and MTHFR genotype with breast cancer risk.

We conducted a hospital-based case-control study to investigate the associations of dietary intake of folate and MTHFR C677T and A1298C polymorphisms with breast cancer in a Chinese population. A 1:1-matched case-control study was conducted. Two hundred and thirty patients who were newly diagnosed and histologically confirmed breast cancer and 230 controls were enrolled from Xinxiang Central Hospital. Folate intake was calculated by standard portion size and relative size for each food item in the questionnaire. Genotyping of MTHFR C677T and A1298C was performed by PCR-RFLP. MTHFR 677TT (OR = 2.26, 95%CI = 1.09-4.87, P = 0.02) and T allele (OR = 1.40, 95%CI = 1.03-1.90, P = 0.03) had an increased risk of laryngeal cancer when compared with the CC genotype. We found any interaction between MTHFR C677T and folate intake (P for interaction = 0.02). In conclusion, our study demonstrated that MTHFR C677T polymorphism and folate are associated with risk of breast cancer.

Evaluation of biodegradable paclitaxel-eluting nanofibre-covered metal stents for the treatment of benign cardia stricture in an experimental model.

BACKGROUND: Benign strictures at the cardia are troublesome for patients and often require repeated endoscopic treatments. Paclitaxel can reduce fibrosis. This study evaluated a biodegradable paclitaxel-eluting nanofibre-covered metal stent for the treatment of benign cardia stricture in vitro and in vivo. METHODS: Drug release was investigated in vitro at pH 7·4 and 4·0. Eighty dogs were divided randomly into four groups (each n = 20): controls (no stent), bare stent (retained for 1 week), and two drug-eluting stent (DES) groups with retention for either 1 week (DES-1w) or 4 weeks (DES-4w). Lower oesophageal sphincter pressure (LOSP) and 5-min barium height (5-mBH) were assessed before, immediately after stent deployment, at 1 week, and 1, 3 and 6 months later. Five dogs in each group were killed for histological examination at each follow-up point. RESULTS: Stent migration rates were similar (0 bare stent versus 2 DES; P = 0·548). The percentage and amount of paclitaxel released in vitro was higher at pH 4·0 than at pH 7·4. After 6 months, LOSP and 5-mBH were both improved in the DES-1w (P = 0·004 and P = 0·049) and DES-4w (both P < 0·001) groups compared with the bare-stent group, with better relief when the stent was retained for 4 weeks (P = 0·004 and P = 0·007). The DES was associated with a reduced peak inflammatory reaction and less scar formation compared with bare stents, especially when inserted for 4 weeks. CONCLUSION: The DES was more effective for the treatment of benign cardia stricture than bare stents in a canine model. Retention of the DES for 4 weeks led to a better clinical and pathological outcome than 1 week.

Biodegradable rapamycin-eluting nano-fiber membrane-covered metal stent placement to reduce fibroblast proliferation in experimental stricture in a canine model.

BACKGROUND AND STUDY AIMS: The aim of the current study was to assess whether placement of the biodegradable rapamycin-eluting nano-fiber membrane-covered metal stent is followed by less fibroblast proliferation and tissue hyperplasia compared with bare stents in experimental stricture in a dog model. METHODS: A total of 80 dog models of stricture were randomly divided into a control group (n = 20, no stent insertion), a bare stent group (BSG, n = 20, 1-week retention), and two drug-eluting stent sub-groups (DESG-1w, n = 20, 1-week retention; DESG-4w, n = 20, 4-week retention). Lower esophageal sphincter (LES) pressure, 5-minute barium height (5-mBH), and cardia diameter were assessed before, immediately after the procedure, and regularly thereafter for 6 months. Five dogs in each group were euthanized for histological examination at each follow-up assessment. RESULTS: Stent insertion was well tolerated, with similar migration rates (0 % in BSG vs. 7.5 % in DESGs; P = 0.5441). At 6 months, LES pressure and 5-mBH improved in DESG-1w (26.70 ± 5.02 mmHg and 6.50 ± 2.98 cm) and DESG-4w (20.16 ± 5.50 mmHg and 1.54 ± 0.98 cm) compared with BSG (39.94 ± 5.22 mmHg and 11.1 ± 5.46 cm) (P < 0.05), with DESG-4w being more stable than DESG-1w (P < 0.05). The cardia maintained greater patency in the DESGs (7.10 ± 3.09 mm in DESG-1w; 9.16 ± 3.77 mm in DESG-4w) than in the BSG (1.86 ± 2.45 mm; P < 0.05). Reduced peak inflammatory reactions and scarring occurred in DESGs compared with the BSG (P < 0.05), with a better outcome in DESG-4w than in DESG-1w (P < 0.05). CONCLUSIONS: In this experimental stricture model, rapamycin-eluting stents were more effective than bare stents for the reduction of fibroblast proliferation and tissue hyperplasia after stent placement. Furthermore, 4-week retention of the drug-eluting stent led to a better outcome than 1-week retention.

A generic plant RNA isolation method suitable for RNA-Seq and suppression subtractive hybridization.

A recently developed revolutionary approach to transcriptomics, RNA-Seq, and suppression subtractive hybridization are powerful tools for gene expression research. However, currently, the difficulty of isolating high-quality RNAs from plant tissues bearing abundant complex polysaccharides, polyphenolics, and secondary metabolites is a serious problem that not only limits the application of these technologies but also hinders studies dealing with RNA in general. We have developed a consistent protocol to prepare highly intact and pure RNAs from tissues of a variety of field-grown plant species, with high yields, in 2 to 3 h. Additionally, this method can be readily applied to mammalian, yeast, and bacterial cells.