Effects of therapeutic hypercapnia on the expression and function of γδT cells in transplanted lungs in rats

OBJECTIVE

To investigate the effect of therapeutic hypercapnia on the expression and function of gamma delta T (γδ T) cells during ischemia-reperfusion injury (IRI) after lung transplantation.

METHODS

We randomly divided male Wistar rats into three groups (n = 6 in each group), the control group (group N), the IRI group (group I), and the therapeutic hypercapnia group (group H). We then assessed pulmonary edema, neutrophil infiltration, wet-to-dry (W/D) weight ratio, and microscopic histopathology and separately measured the levels of γδT cell surface antigen (TCR) and Interleukin-17 (IL-17) using flow cytometry and enzyme-linked immunosorbent assays (ELISAs).

RESULTS

The infiltration of neutrophils and the expression of TCR and IL-17 were significantly increased in the I group compared to the control, and the biopsy edema in group I was more severe. Arterial partial pressure of oxygen (PaO2) was decreased after reperfusion in group I compared with the control group. W/D weight ratio, neutrophil infiltration, and the expression of TCR and IL-17 decreased drastically in the H group compared to the I group.

CONCLUSION

Our findings suggest that γδ T lymphocytes were directly involved in lung injury. In addition, therapeutic hypercapnia effectively reduced the expression of γδ T cells and IL-17, and this has the potential to become a treatment strategy for IRI and an intervention to improve lung function.

Numerical simulation and testing of laser-MIG hybrid-welding angle-structure sheets

Numerical simulation and experimental investigation of laser-MIG hybrid angle-welding low-carbon 1.5-mm-thin SPCC steel sheets are presented in this work. The transient simulation analysis provides an access to the thermal-fluid phenomena prediction by employing a hybrid three-dimensional heat source model. Special attention is paid to the melt dynamic behaviors within the triangular molten pool affected by the Marangoni convection. The simulation results show that the temperature and its gradient distribution are symmetrical with respect to the laser beam, which is validated well by the experimental study. The microstructure of the welded joints was analyzed by scanning electron microscopy and transmission electron microscopy. The results show that the cross-section microstructures of welded joint are mainly composed of the weld zone, narrow heat-affected zone, and substrate. The semielliptic-like molten pool shape is consistent with that of the simulated results. The finer microstructure in the weld bead results from the rapid cooling rate of laser welding confirmed by the FEM calculation. The columnar and equiaxed dendrites are formed in the peripheral and central region of the molten pool, which is beneficial for the improvement of the microhardness.

[Short-term efficacy of empagliflozin in children with glycogen storage disease type Ⅰb]

Objective: To analyze the short-time efficacy of empagliflozin in the treatment of glycogen storage disease type Ⅰb (GSD Ⅰb). Methods: In this prospective open-label single-arm study, the data of 4 patients were collected from the pediatric department in Peking Union Medical College Hospital from December 2020 to December 2022. All of them were diagnosed by gene sequencing and had neutropenia. These patients received empagliflozin treatment. Their clinical symptoms such as height and weight increase, abdominal pain, diarrhea, oral ulcer, infection times, and drug applications were recorded at 2 weeks, 1 month, 2 months, 3 months, 6 months, 9 months, 12 months, and 15 months after treatment to assess the therapeutic effect. The liquid chromatography-tandem mass spectrometry method was used to monitor the changes in 1, 5-anhydroglucitol (1, 5AG) concentration in plasma. At the same time, adverse reactions such as hypoglycemia and urinary tract infection were closely followed up and monitored. Results: The 4 patients with GSD Ⅰb were 15, 14, 4 and 14 years old, respectively at the beginning of empagliflozin treatment, and were followed up for 15, 15, 12 and 6 months, respectively. Maintenance dose range of empagliflozin was 0.24-0.39 mg/(kg·d). The frequency of diarrhea and abdominal pain decreased in cases 2, 3, and 4 at 1, 2 and 3 months of treatment, respectively. Their height and weight increased at different degrees.The absolute count of neutrophils increased from 0.84×10⁹, 0.50×10⁹, 0.48×10⁹, 0.48×10⁹/L to 1.48×10⁹, 3.04×10⁹, 1.10×10⁹, 0.73×10⁹/L, respectively. Granulocyte colony-stimulating factor was gradually reduced in 1 patients and stopped in 3 patient. Plasma 1, 5 AG levels in 2 children were significantly decreased after administration of empagliflozin (from 46.3 mg/L to 9.6 mg/L in case 2, and from 56.1 mg/L to 15.0 mg/L in case 3). All 4 patients had no adverse reactions such as hypoglycemia, abnormal liver or kidney function, or urinary system infection. Conclusion: In short-term observation, empagliflozin can improve the symptoms of GSD Ⅰb oral ulcers, abdominal pain, diarrhea, and recurrent infection, also can alleviate neutropenia and decrease 1, 5AG concentration in plasma, with favorable safety.

Resolution of herpes zoster-induced small bowel pseudo-obstruction by epidural nerve block: A case report

BACKGROUND

When herpes zoster is complicated with paralytic ileus, this mostly involves acute intestinal pseudo-obstruction of Ogilvie’s syndrome manifesting as obvious dilatation of the cecum and right colon; small intestinal obstruction is rare. Here, we present a patient with a very rare case of small bowel pseudo-obstruction.

CASE SUMMARY

A 76-year-old female patient complained of right upper quadrant pain. Two days later, a blistering, right-sided rash of the thoracoabdominal dermatome (T5-T10) emerged in conjunction with small intestinal dilatation and the inability to defecate. Computed tomography of the abdomen confirmed small bowel pseudo-obstruction. Antiviral therapy, gastrointestinal decompression, and enemas proved unproductive. After 4 d of stagnation, an epidural block was performed for pain relief and prompted the passage of gas and stool, resolving the obstructive problem. Three days later, the rash appeared dry and crusted, and the pain diminished. After 5 d, no abnormality was visible by gastroenteroscopy, and the patient was discharged on day 7.

CONCLUSION

This case shows that herpes zoster may induce small bowel pseudo-obstruction in addition to colonic pseudo-obstruction. Epidural block can not only treat intercostal neuralgia but also resolve small bowel pseudo-obstruction caused by herpes zoster.

Effects of powder size and preset thickness on the microstructure and properties of Ni35 thin coating prepared by laser cladding

Ni35 thin coatings were prepared on 40Cr steel by preset powder laser cladding technology. The effects of powder size and preset thickness on the dilution rate, microstructure, and properties of the coating were systematically studied. The results showed that the coating with smaller powder size and larger preset thickness had smaller grain size, denser microstructure, a flatter bottom of the molten pool, and lower dilution rate. The micro-hardness of the coating with large powder size and preset thickness was higher. The friction coefficient of the coating with small powder size and small preset thickness was smaller, but the latter had larger curve fluctuation and wear volume loss. The corrosion rate of the coating was high during the first 24 h, then relatively stable after 68 h, and the corrosion rate and loss of the coating with small powder size and large preset thickness were smaller.

Microstructure evolution and wear behavior of AISI 304 stainless steel after Nd:YAG pulsed laser surface melting

The microstructure and wear behavior of AISI 304 stainless steel after Nd:YAG pulsed laser surface melting (LSM) were investigated. The microstructural features of the LSM layer were characterized by field emission scanning electron microscope and high-resolution transmission electron microscope. Experimental results showed that the microstructure was obviously refined to the nano- and sub-micrometer scales on the AISI 304 stainless steel surface after LSM treatment. Fine grains with grain size of less than 200 nm were obtained when the applied laser energy densities were in the range of 1.90×10⁷ to 3.52×10⁷J/m² during LSM. The results indicated that the calculated surface temperature, cooling rate, and measured grain size are closely related to the adopted laser energy densities. The lower the laser energy density is, the lower the surface temperature, and the faster the cooling rate, the finer the grain size. In addition, the microhardness and wear resistance of the stainless steel was significantly improved. Finally, the wear mechanism after LSM process was revealed.

[Layer-specific strain assessment on left ventricular function before and after PCI in patients with ST segment elevation myocardial infarction]

Objective: To evaluate the changes of left ventricular function in patients with ST segment elevation myocardial infarction (STEMI) before PCI and within 24 hours after PCI by layer-specific strain, and to explore the value of this new assessment method for quantitative monitoring on the myocardial function in STEMI patients. Methods: A total of 40 patients with acute anterior wall myocardial infarction, who underwent PCI in Affiliated Hospital of Jiangsu University during July 2017 to July 2018, were included in this prospective cohort study. According to the symptom to balloon time (STB), the patients were divided into STB ≤6 hours group (26 cases) and STB 6-12 hours group (14 cases). Echocardiography was performed before, immediately, 3 hours and 24 hours after PCI. Echocardiographic indexes including endocardial myocardial longitudinal strain (LS-endo), 18-segment full-thickness myocardial longitudinal strain (LS) of left ventricle and left ventricular global longitudinal strain (GLS) were measured. The mean LS-endo and LS values of myocardial segments in infarcted area (IALS-endo, IALS) and the mean LS-endo and LS values of myocardial segments in non-infarcted area (NIALS-endo, NIALS) were calculated. Results: There were 34 males and 6 females in this cohort and age was (62±10) years. In STB≤6 hours group, the IALS-endo value ((13.7±4.9)% vs. (10.0±2.7)%, P<0.05) and NIALS-endo value ((17.0±2.9)% vs. (14.6±2.9)%, P<0.05) were significantly higher at 24 hours after PCI than those before PCI. In the group of STB 6-12 hours, IALS-endo decreased immediately after PCI ((6.7±3.3)% vs. (11.9±6.5)%, P<0.05), and there was a rising trend at 3 hours after PCI (P>0.05). At 24 hours after PCI, the index was higher than that immediately after PCI ((13.6±8.4)% vs. (6.7±3.3)%, P<0.05). The NIALS-endo value was significantly higher at 24 hours after PCI than that before PCI ((17.1±2.1)% vs. (14.5±3.2)%, P<0.05). In the STB 6-12 hours group, the decrease rate of IALS-endo immediately after PCI was higher than that in the STB ≤6 hours group (93% (13/14) vs. 35% (9/26), P<0.001). In STB ≤6 hours group, the NIALS value at 24 hours after PCI was higher than that before PCI (P<0.05), and there was no significant difference in IALS, NIALS and GLS at other time points (P>0.05). Conclusions: Layered LS is superior to full-thickness LS and GLS in evaluating left ventricular function in STEMI patients. LS measured by echocardiography can continuously and quantitatively evaluate the changes of left ventricular myocardial function in STEMI patients before and after PCI.

Curcumin alleviates oxidative stress and inhibits apoptosis in diabetic cardiomyopathy via Sirt1-Foxo1 and PI3K-Akt signalling pathways

Diabetes is a disorder of glucose metabolism, and over 90% are type 2 diabetes. Diabetic cardiomyopathy (DCM) is one of the type 2 diabetes complications, usually accompanied by changes in myocardial structure and function, together with cardiomyocyte apoptosis. Our study investigated the effect of curcumin on regulating oxidative stress (OS) and apoptosis in DCM. In vivo, diabetes was induced in an experimental rat model by streptozoticin (STZ) together with high‐glucose and high‐fat (HG/HF) diet feeding. In vitro, H9c2 cardiomyocytes were cultured with high‐glucose and saturated free fatty acid palmitate. Curcumin was orally or directly administered to rats or cells, respectively. Streptozoticin ‐induced diabetic rats showed metabolism abnormalities and elevated markers of OS (superoxide dismutase [SOD], malondialdehyde [MDA], gp91^phox, Cyt‐Cyto C), enhanced cell apoptosis (Bax/Bcl‐2, Cleaved caspase‐3, TUNEL‐positive cells), together with reduced Akt phosphorylation and increased Foxo1 acetylation. Curcumin attenuated the myocardial dysfunction, OS and apoptosis in the heart of diabetic rats. Curcumin treatment also enhanced phosphorylation of Akt and inhibited acetylation of Foxo1. These results strongly suggest that apoptosis was increased in the heart of diabetic rats, and curcumin played a role in diabetic cardiomyopathy treatment by modulating the Sirt1‐Foxo1 and PI3K‐Akt pathways.

[Impact of CD137-CD137L signaling on secretion of mouse vascular smooth muscle cells-derived exosomes: role of Rab7 pathway]

Objective: To investigate whether CD137-CD137L signaling could affect the secretion of mouse vascular smooth muscle cells (VSMCs) -derived exosomes through autophagy mediated Rab7 pathway. Methods: Primary thoracic aorta VSMCs from C57BL/6J mouse were obtained by tissue block adherence method. VSMCs between the third to fifth passages were used and VSMCs were divided into 4 groups: control group, CD137 agonist group, lentivirus control group, Rab7 lentiviral interference group. VSMCs in CD137 agonist group were treated with recombinant protein of CD137L (10 μg/ml), VSMCs in lentivirus control group were treated with lentiviral followed by recombinant protein of CD137L (10 μg/ml), VSMCs in Rab7 lentiviral interference group were treated with Rab7 lentiviral intervention followed by recombinant protein of CD137L (10 μg/ml). Western blot was used to detect the protein expression of LC3Ⅱ, p62, Rab7, CD9, CD81 and Hsc70. Fluorescence microscopy was used to track the changes of autophagy in cells infected with mRFP-GFP-LC3. Transmission electron microscope was used to observe the morphology and size of VSMCs-derived exosomes. The nanoparticle tracking analysis(NTA) was used to detect the concentration and size of exosomes in each group. Results: (1) The expressions of Rab7, LC3Ⅱ and p62 protein in VSMCs of CD137 activation group were significantly higher than those in control group (all P<0.05). The expressions of Rab7, LC3Ⅱ and p62 protein in Rab7 lentivirus interference group was lower than in CD137 activation group (all P<0.05), while the expressions were similar between the lentivirus control group and the CD137 activation group (all P>0.05). (2) The total number of fluorescent spots and yellow fluorescent spots in the VSMCs of the CD137 activation group were higher than those in the control group (all P<0.05), and the number of yellow fluorescent spots was higher than that of the red fluorescent spots in the VSMCs of the CD137 activation group ((50.3±0.9) vs. (10.3±1.5)/cell). The total numbers of fluorescent spots and yellow fluorescent spots in VSMCs of Rab7 lentivirus interference group were lower than those of CD137 activation group (both P<0.05), and the number of red fluorescent spots in VSMCs was higher than that of yellow fluorescent spots ((40.7±4.0) and (10.7±1.2)/cell) in the Rab7 lentiviral interference group. The total numbers of fluorescent spots and yellow fluorescent spots in the VSMCs were similar between the lentivirus control group and the CD137 activation group (all P>0.05). (3) Under transmission electron microscopy, the size of the VSMCs-derived exosomes was about 30-150 nm. The exosome markers (CD9, CD81) could be detected in vesicles by Western blot. NTA results showed that the concentration of VSMCs-derived exosomes was significantly higher in the CD137-activated group than in the control group (P<0.05), which was significantly lower in the Rab7 lentiviral interference group than in the CD137-activation group (P<0.05) and was similar between the lentivirus control group and the CD137 activation group (P>0.05). The expression of Hsc70 protein in exosomes secreted by CD137 activation group was higher than that in the control group (P<0.05). The expression of Hsc70 protein in exosomes was lower in Rab7 lentivirus interference group than in the CD137 activation group (P<0.05), which was similar between the lentivirus control group and the CD137 activation group (P>0.05). The expression of LC3Ⅱ protein in exosome was higher in CD137 activation group than in control group (P<0.05), which was lower in Rab7 lentivirus interference group than in CD137 activation group (P<0.05), which was similar between the lentivirus control group and the CD137 activation group (P>0.05). Conclusion: The CD137-CD137L signaling may affect the secretion of mouse VSMCs-derived exosomes through modulating the Rab7 pathway mediated autophagy.

Optimal Dexmedetomidine Dose to Prevent Emergence Agitation Under Sevoflurane and Remifentanil Anesthesia During Pediatric Tonsillectomy and Adenoidectomy

Background: Emergence agitation (EA) is a common pediatric complication after sevoflurane anesthesia that can be prevented with dexmedetomidine. However, an inappropriate dose of dexmedetomidine can cause prolonged sedation and cardiovascular complications. Thus, we evaluated the optimal dose (ED95) of dexmedetomidine for preventing EA with sevoflurane and remifentanil anesthesia after pediatric tonsillectomy and adenoidectomy.

Methods: We enrolled American Society of Anesthesiologists (ASA) I and II children 3–7 years of age who underwent tonsillectomy with adenoidectomy. During induction, dexmedetomidine was infused for 10 min. Anesthesia was induced with sevoflurane and maintained with sevoflurane and remifentanil, resulting in a bispectral spectrum index (BIS) range from 40 to 60. Extubation time, surgical and anesthetic duration time, and duration time in the postanesthesia care unit (PACU) stay were recorded. EA [measured with Pediatric Anaesthesia Emergence Delirium (PAED) scores] and pain [measured with Face, Legs, Activity, Cry, Consolability (FLACC) scores] were assessed at extubation (E0), 15 min after extubation (E1), and 30 min after extubation (E2). If EA occurred, the next surgical procedure included increased dexmedetomidine by 0.1 μg/kg, and if not, the drug was reduced by 0.1 μg/kg.

Results: The 50% effective dose (ED50) of dexmedetomidine for preventing EA after sevoflurane and remifentanil anesthesia for tonsillectomy and adenoidectomy was 0.13 μg/kg, and its 95% confidence interval is 0.09–0.19 μg/kg; ED95 was 0.30 μg/kg, and its 95% confidence interval is 0.21–1.00 μg/kg.

Conclusion: Intravenous dexmedetomidine infusion at ED50 (0.13 μg/kg) or ED95 (0.30 μg/kg) during induction for 10 min can prevent half or almost all EA after sevoflurane and remifentanil anesthesia during pediatric tonsillectomy and adenoidectomy.

Endothelial progenitor cells attenuate the lung ischemia/reperfusion injury following lung transplantation via the endothelial nitric oxide synthase pathway

OBJECTIVE

Endothelial progenitor cells (EPCs) can improve endothelial integrity. This study aimed to examine the effects and the mechanism of EPCs on lung ischemia-reperfusion injury (LIRI).

METHODS

Wistar rats were randomized into the sham or the left lung transplantation group. The recipients were randomized and treated with vehicle as the LIRI group, with EPC as the EPC group, or with N5-(1-iminoethyl)-l-ornithine-pretreated EPC as the EPC/L group (n = 8 per group). The ratios of arterial oxygen partial pressure to fractional inspiratory oxygen were measured. The lung wet-to-dry weight ratios, protein levels, and injury, as well as the levels of plasma cytokines, were examined. The levels of endothelin (ET)-1, endothelial nitric oxide synthase (eNOS), phosphorylated eNOS, inducible NOS, phosphorylated myosin light chain, nuclear factor-κBp65, Bax, Bcl-2, cleaved caspase-3, and myeloperoxidase in the graft lungs were detected.

RESULTS

Compared with the LIRI group, EPC treatment significantly increased the ratios of arterial oxygen partial pressure to fractional inspiratory oxygen and decreased the lung wet-to-dry weight ratios and protein levels in the grafts, accompanied by increasing eNOS expression and phosphorylation, but decreasing endothelin-1, inducible NOS, phosphorylated nuclear factor-kBp65, phosphorylated myosin light chain expression, and myeloperoxidase activity. EPCs reduced lung tissue damage and apoptosis associated with decreased levels of Bax and cleaved caspase-3 expression, but increased Bcl-2 expression. EPC treatment significantly reduced the levels of serum proinflammatory factors, but elevated levels of interleukin-10. In contrast, the protective effect of EPCs were mitigated and abrogated by N5-(1-iminoethyl)-l-ornithine pretreatment.

CONCLUSIONS

Data indicated that EPC ameliorated LIRI by increasing eNOS expression.

Effect of preoperative inhaled budesonide on pulmonary injury after cardiopulmonary bypass: A randomized pilot study

BACKGROUND

Cardiopulmonary bypass can result in lung injury. This prospective, double-blinded, randomized trial aimed to evaluate the protective effect of inhaled budesonide on lung injury after cardiopulmonary bypass.

METHODS

Sixty patients, aged 25 to 65 years, requiring cardiopulmonary bypass were randomized to groups treated with saline or budesonide inhalation preoperatively. The respiratory mechanics were recorded. Bronchoalveolar lavage fluid was collected before cardiopulmonary bypass and after sternal closure. Serum and bronchoalveolar lavage fluid levels of proinflammatory and anti-inflammatory factors were analyzed. The primary end point was the lowest ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen after cardiopulmonary bypass. The durations of ventilation and postoperative recovery time were noted.

RESULTS

Budesonide significantly improved respiratory mechanics after cardiopulmonary bypass. Budesonide improved the partial pressure of arterial oxygen to the fraction of inspired oxygen ratio from 8 to 48 hours after the operation. Budesonide shortened the durations of mechanical ventilation and postoperative recovery time. Budesonide decreased the levels of proinflammatory factors while increasing the levels of anti-inflammatory factors in bronchoalveolar lavage fluid and serum (all P < .05). The macrophage and neutrophil counts, and protein and elastase concentrations were decreased by budesonide treatment.

CONCLUSIONS

Budesonide treatment shortened the durations of mechanical ventilation, inhibited local and systemic inflammation, and improved respiratory function after cardiopulmonary bypass.

Adiponectin protects against lung ischemia-reperfusion injury in rats with type 2 diabetes mellitus

Adiponectin (APN) has been associated with the pathogenesis of acute brain, liver and heart injury. However, the role of APN in lung ischemia-reperfusion injury (LIRI) in diabetes mellitus remains unclear. To investigate this, the present study evaluated the effects of APN on lung dysfunction and pathological alterations in rats with type 2 diabetes mellitus via lung ischemia/reperfusion (I/R). The lung‑protective effects of APN globular domain (gAPN) in rats with type 2 diabetes mellitus were also investigated by measuring the oxygenation index, inflammatory cytokines, lung edema, histopathology, oxidative stress, apoptosis and the protein expression levels of phosphorylated 5'adenosine monophosphate‑activated protein kinase (p‑AMPK), endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS). The results of the present study demonstrated that the diabetes mellitus rats + I/R (DIR) group exhibited greater concentrations of tumor necrosis factor‑α and interleukin‑6, and increases in the wet‑weight to dry‑weight ratio, lung injury score, oxidative stress and cellular apoptosis. These effects were accompanied by lower pulmonary oxygenation compared with the normal rat + I/R (NIR) group (P<0.05). Additionally, all of these alterations were attenuated in the NIR + gAPN and DIR + gAPN groups compared with in the NIR and DIR groups, respectively. In the DIR group, the expression levels of p‑AMPK/AMPK and eNOS were significantly downregulated, and the levels of iNOS were upregulated, compared with those of the NIR group. Treatment with APN activated AMPK, increased eNOS expression and attenuated iNOS expression. The results of the present study demonstrated that APN exerted protective effects against LIRI via its anti‑inflammatory, antioxidative stress and anti‑apoptotic activities. These protective effects of APN were eliminated in rats with type 2 diabetes mellitus, in which LIRI was exacerbated. The present study indicated that APN may be a potential therapeutic agent for LIRI in type 2 diabetes mellitus.

Budesonide instillation immediately after reperfusion ameliorates ischemia/reperfusion-induced injury in the transplanted lung of rat

PURPOSE

Lung ischemia-reperfusion injury (LIRI) after lung transplantation can lead to primary graft dysfunction. Budesonide can improve endothelial function to reduce lung injury. This study was aimed to examine the effects of budesonide on LIRI and potential mechanisms.

METHODS

Wistar rats were randomized and transplanted with syngeneic left lung or received the sham surgery. The recipients were instilled with saline or budesonide immediately after reperfusion. The mean arterial pressure (MAP), blood gas, and lung histology were analyzed. The ratios of wet to dry lung weights, the levels of total proteins, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10, and neutrophil elastase in bronchoalveolar lavage fluid (BALF) were measured. The levels of malondialdehyde (MDA), myeloperoxidase (MPO), and xanthine oxidase (XO) in the lung, and the levels of plasma lymphocyte function-associated antigen (LFA)-1 and P-selectin were determined.

RESULTS

Compared with the saline group, treatment with budesonide significantly increased blood PaO₂, but reduced PaCO₂, and mitigated lung damages after reperfusion, the levels of BALF proteins, and the ratios of wet to dry lung weights in rats. Furthermore, treatment with budesonide significantly decreased the levels of MDA, MPO, and XO in the lung and the levels of TNF-α, IL-1β, IL-6, and neutrophil elastase, but increased IL-10 in the BALF, accompanied by significantly reduced levels of serum P-selectin and LFA-1 in rats.

CONCLUSIONS

Budesonide effectively mitigated LIRI and ameliorated the lung function by attenuating oxidative stress and inflammation following syngeneic lung transplantation.

Low dose of dexmedetomidine as an adjuvant to bupivacaine in cesarean surgery provides better intraoperative somato-visceral sensory block characteristics and postoperative analgesia

Object

In this study, we aimed to investigate the beneficial effects of dexmedetomidine on somato-visceral sensory block characteristcs, postoperative analgesia and stress response of intrathecal bupivacaine administration in women undergoing cesarean section, and to find out which dose is better.

Methods

Sixty parturients with the American Society of Anesthesiologists (ASA) physical status I or II were anesthetized with intrathecal bupivacaine(10mg) alone or in combination with dexmedetomidine (3 μg and 5 μg) to undergo cesarean section. The anesthetic parameters, postoperative analgesia and stress responses were monitored.

Results

Co-administration of dexmedetomidine(3 μg and 5 μg) prolonged the duration of motor and sensory block compared with bupivacaine(10mg) alone. Less supplemental dose of lidocaine and fentanyl were required in dexmedetomidine(3 μg and 5 μg) co-administration groups. Visceral traction response and abdominal muscle relaxation in operation were better in dexmedetomidine(3 μg and 5 μg) co-administration groups. No difference in haemodynamics was detected among groups. There was no significant difference in Apgar scores, neonatal umbilical pH, oxygen pressure, carbon dioxide pressure and lactate level among groups. Postoperative plasma IL-6 and cortisol levels were lower in dexmedetomidine(3 μg and 5 μg) co-administration groups. At 6 hour after operation the visual analogue scale (VAS) was smaller in dexmedetomidine(3 μg and 5 μg) co-administration groups. The uterine contraction pain at 6 and 12 hour after operation and supplemental analgesics had no difference across three groups. No difference of side effects(shivering, nausea and vomiting, itching), the first anal aerofluxus time and intraoperation tramadol dose were detected among the three groups.

Conclusion

The use of dexmedetomidine especially at the dose of 3μg as an adjuvant to bupivacaine in cesarean surgery provides better intraoperative somato-visceral sensory block characteristcs and postoperative analgesia, which produced no influence on Apgar scores, side effects and stress response.

[Drug-Resistant Mechanism of Multiple Myeloma and Its Therapy Combined with HDACi -Review]

Drug resistance of multiple myeloma(MM) has become more and more common, and greatly decreased the survival rate of these patients. The occurence of drug-resistance involves in many factors such as bone marrow microenveronment, tumor cell self-metabolism, cytokines, specific targets and so on. In this review, the potential mechanisms of resistance to glucocorticoid/proteasome inhibitor/immunomodulatory druges are briefly expounded in the aspect of tumor cell self-metabolism, including the changes of heat slock protein expression, mRNA expression, related cytokine levels and down-regulation of thalidomid-effecting site CRBN expression. In this review, the researches on the effect of histone deacetylase inhibitors(HDACi) combined with glucocorticoid, proteasome inhibitors, immunomodulatory drugs and monoclonal antibodies on multiple myeloma, specially, drug-resistant multiple myeloma are also summarized.

Epidural Co-Administration of Dexmedetomidine and Levobupivacaine Improves the Gastrointestinal Motility Function after Colonic Resection in Comparison to Co-Administration of Morphine and Levobupivacaine

Gastrointestinal motility may be impaired after intestinal surgery. Epidural morphine is effective in controlling postoperative pain, but can further reduce gastrointestinal motility. Here, we aimed to investigate the effects of epidural dexmedetomidine on gastrointestinal motility in patients undergoing colonic resection. Seventy-four patients undergoing colonic resection were enrolled in this clinical trial and allocated randomly to treatment with dexmedetomidine (D group) or morphine (M group). The D group received a loading dose epidural administration of 3 ml dexmedetomidine (0.5 μg kg(-1)) and then a continuous epidural administration of 80 μg dexmedetomidine in 150 ml levobupivacaine (0.125%) at 3 ml h(-1) for two days. The M group received a loading dose epidural administration of 3 ml morphine (0.03 mg kg(-1)) and then a continuous epidural administration of 4.5 mg morphine in 150 ml levobupivacaine at 3 ml h(-1) for two days. Verbal rating score (VRS), postoperative analgesic requirements, side effects related to analgesia, the time to postoperative first flatus (FFL) and first feces (FFE) were recorded. VRS and postoperative analgesic requirements were not significantly different between treatment groups. In contrast, the time to FFL and time to FFE were significant longer in M group in comparison to D group (P < 0.05). Moreover, patients in M group had a significantly higher incidence of nausea, vomiting, and pruritus (P < 0.05). No patients showed neurologic deficits in either group. In comparison to morphine, epidural dexmedetomidine is safe and beneficial for the recovery of gastrointestinal motility after colonic resection when used as an adjunct with levobupivacaine for postoperative pain control.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-TRC-14004644.

Roll up polymer/oxide/polymer nanomembranes as a hybrid optical microcavity for humidity sensing

A hybrid optical microcavity from rolled-up polymer/oxide/polymer nanomembranes presents its excellent capability for environmental relative humidity detection. When exposed to a moist surrounding, poly(acrylic acid)/poly(ethylenimine) polymers swell greatly due to the absorption of water molecules, which thus leads to an increased wall thickness of the tubular optical microcavity and therefore presents a profound wavelength redshift of its whispering-gallery mode resonance. These experiments fit well with the calculation based on the Mie-scattering theory. Theoretical calculation also demonstrates that the thin walls of our tubular microcavities contribute to a high detection sensitivity compared to other microcavities. Our work could lead to new designs and applications of optical microcavities.

Low-dose epidural dexmedetomidine improves thoracic epidural anaesthesia for nephrectomy

Thoracic epidural anaesthesia alone is an applied technique of anaesthesia for nephrectomy which has both advantages and limitations. Dexmedetomidine is a highly selective alpha2-adrenoreceptor agonist which has both central and peripheral analgesic properties. Forty patients undergoing nephrectomy were enrolled in this clinical trial and allocated randomly to two groups, a control group (C group) and a dexmedetomidine group (D group). The C group received epidural 0.75% levobupivacaine 12 ml with 1 ml of isotonic sodium chloride solution, while the D group received epidural 0.75% levobupivacaine 12 ml with 1 ml (0.5 µg/kg) of dexmedetomidine. Haemodynamic changes, onset time and duration of sensory and motor block, muscle relaxation score, verbal rating score for pain, sedation score and the total postoperative analgesic consumption were evaluated. Sensory blockade duration was longer in the D group than in the C group (P=0.01). The incidence of motor block and the muscle relaxation score were significantly higher in the D group compared with the C group (P=0.01). Compared with the C group, pain scores were significantly lower in the first four postoperative hours in the D group (two hours rest P=0.038; two hours activity P=0.009; four hours rest P=0.044; four hours activity P=0.003). The total amount of flurbiprofen analgesic was significantly lower in the D group compared with the C group (P=0.03). Epidural dexmedetomidine 0.5 µg/kg appears to intensify thoracic epidural anaesthesia with levobupivacaine.

Hypercapnic acidosis confers antioxidant and anti-apoptosis effects against ventilator-induced lung injury

Hypercapnic acidosis may attenuate ventilator-induced lung oxidative stress injury and alveolar cell apoptosis, but the underlying mechanisms are poorly understood. We examined the effects of hypercapnic acidosis on the role of apoptosis signal-regulating kinase 1 (ASK1), which activates the c-Jun N-terminal kinase (JNK) and p38 cascade in both apoptosis and oxidative reactions, in high-pressure ventilation stimulated rat lungs. Rats were ventilated with a peak inspiratory pressure (PIP) of 30 cmH2O for 4 h and randomly given FiCO2 to achieve normocapnia (PaCO2 at 35-45 mm Hg) or hypercapnia (PaCO2 at 80-100 mm Hg); normally ventilated rats with PIP of 15 cmH2O were used as controls. Lung injury was quantified by gas exchange, microvascular leaks, histology, levels of inflammatory cytokines, and pulmonary oxidative reactions. Apoptosis through the ASK1-JNK/p38 mitogen-activated protein kinase (MAPK) cascade in type II alveolar epithelial cells (AECIIs) were evaluated by examination of caspase-3 activation. The results showed that injurious ventilation caused significant lung injury, including deteriorative oxygenation, changes of histology, and the release of inflammatory cytokines. In addition, the high-pressure mechanical stretch also induced apoptosis and caspase-3 activation in the AECIIs. Hypercapnia attenuated these responses, suppressing the ASK1 signal pathways with its downstream kinase phosphorylation of p38 MAPK and JNK, and caspase-3 activation. Thus, hypercapnia can attenuate cell apoptosis and oxidative stress damage in rat lungs during injurious ventilation, at least in part, due to the suppression of the ASK1-JNK/p38 MAPK pathways.

{μ-6,6'-Dimeth-oxy-2,2'-[butane-1,4-diylbis(nitrilo-methanylyl-idene)]diphenolato}trinitratocopper(II)samarium(III)

In the monomeric dinuclear title complex, [CuSm(C(20)H(22)N(2)O(4))(NO(3))(3)], the four-coordinate Cu(II) ion has a square-planar geometry involving two O atoms and two N atoms of the deprotonated Schiff base ligand. The Sm(III) ion is ten-coordinate, chelated by four O donor atoms of the Schiff base and two O atoms each from three bidentate nitrate groups, one of which is disordered over two sites in a 0.55 (7):0.45 (7) ratio.

Chronic β-adrenoceptor antagonists upregulate the rat alveolar macrophage adrenergic system through the β1-subtype

BACKGROUND

Previous studies demonstrate that macrophages synthesis and release catecholamines, which regulate the immune responses in an autocrine manner. These responses are mediated in part by β-adrenoceptors expressed on macrophages. Some β-adrenoceptor antagonists are commonly used in clinical conditions. Here we investigated whether the chronic administration of β-adrenoceptor antagonists upregulate adrenergic system of alveolar macrophage and the potential mechanims.

METHODS

Propranolol (30 mg/kg·d) or atenolol (5 mg/kg·d) was administered by gavage to rats for 4 weeks. Then alveolar macrophages were isolated and the expression of β(1) or β(2)-adrenoceptor was detected by flow cytometric analysis. Dopamine β-hydroxylase expression was assessed by Western blot assay and the concentrations of noradrenaline, IL-6, and TNF-α in cell supernatants were measured using ELISA after 2 h or 24 h exposure of alveolar macrophages to 100 ng/ml lipopolysaccharide (LPS).

RESULTS

Propranolol increased the mean fluorescence intensity (MFI) of β(1), β(2)-adrenoceptor and the frequency of β(1)-,β(2)- adrenoceptor positive macrophages. However, only the MFI of β(1)-adrenoceptor and the frequency of β(1)-adrenoceptor positive macrophages were increased by atenolol. Furthermore, both propranolol and atenolol promoted LPS-mediated dopamine β-hydroxylase protein expression and increased noradrenaline production in rat alveolar macrophages. This was accompanied by increased LPS-mediated IL-6 and TNF-α production in cell supernatants of alveolar macrophages.

CONCLUSION

These findings demonstrate that propranolol or atenolol upregulates alveolar macrophage adrenergic system, and the response may be β(1)-adrenergic receptor subtype dependent.

Propofol improved neurobehavioral outcome of cerebral ischemia-reperfusion rats by regulating Bcl-2 and Bax expression

Propofol is an intravenous anesthetic with neuroprotective effects against cerebral ischemia-reperfusion (I/R) injury. Few studies regarding the neuroprotective and neurobehavioral effects of propofol have been conducted, and the underlying mechanisms are still unclear. Because I/R may result in neuronal apoptosis, the apoptosis regulatory genes B-cell leukemia-2 (Bcl-2) and Bcl-2-associated X protein (Bax) may be involved in the neuroprotective process. In this study, 120 Wistar rats were randomly divided into three groups (sham, I/R-induced, and propofol-treated). Cerebral ischemia was induced by clamping the bilateral common carotid arteries for 10min. Propofol (1.0mg/kg/min) was administered intravenously for 1h before the induction of ischemia. Neuronal damage was evaluated by neurobehavioral scores and histological examination of the brain sections at the level of the dorsal hippocampus at 6h, 24h, 48h, 72h, 4days, 5days, 6days, and 7days after I/R. The apoptotic rate of hippocampal neurons was detected by flow cytometry. The expression of Bcl-2 and Bax was evaluated using immunohistochemical and Western blot methods. The results of this study showed that neurobehavioral scores were higher in propofol-treated rats compared with I/R-induced rats with no propofol treatment. Moreover, the hippocampal expression of Bcl-2 was significantly higher, while the expression of Bax was significantly lower in propofol-treated rats compared with I/R-induced rats at 24h after ischemia. Hence, this study suggests that the neuroprotective effects of propofol against neuronal apoptosis may be a consequence of the regulation of Bcl-2 and Bax.

{μ(2)-6,6'-Dimeth-oxy-2,2'-[butane-1,4-diylbis(nitrilo-methyl-idyne)]diphenolato}trinitratocopper(II)neodymium(III)

In the title complex, [CuNd(C₂₀H₂₂N₂O₄)(NO₃)₃], the Cu^II ion is coordinated in a distorted square-planar environment by two O atoms and two N atoms of a tetra­dentate Schiff base ligand. The Nd^III ion is ten-coordinated by three bis-chelating nitrate groups and four O atoms of the Schiff base ligand. The atoms of one of the nitrato ligands are disordered over two sets of sites, with refined occupancies of 0.567 (13) and 0.433 (17).

{μ-6,6'-Dimeth-oxy-2,2'-[propane-1,3-diylbis(nitrilo-methyl-idyne)]-diphenolato}-trinitratocopper(II)lutetium(III) acetone solvate

In the title complex, [CuLu(C(19)H(20)N(2)O(4))(NO(3))(3)]·CH(3)COCH(3), the Cu(II) ion is four-coordinated in a square-planar geometry by two O atoms and two N atoms from the deprotonated Schiff base. The Lu(III) ion is ten-coordinate, chelated by three nitrate groups and linked to the four O atoms of the deprotonated Schiff base. A mol-ecule of acetone is present as a solvate.

Carbon monoxide inhalation ameliorates conditions of lung grafts from rat brain death donors

BACKGROUND

Successful lung transplantation has been limited by the scarcity of donors. Brain death (BD) donors are major source of lung transplantation. Whereas BD process induces acute lung injury and aggravates lung ischemia reperfusion injury. Carbon monoxide (CO) inhalation at 50-500 parts per million (ppm) can ameliorate lung injury in several models. We examined in rats whether CO inhalation in BD donor would show favorable effects on lung grafts.

METHODS

Rats were randomly divided into 4 groups. In sham group, donor rats received insertion of a balloon catheter into the cranial cavity, but the balloon was not inflated. In BD-only group, donor rats were ventilated with 40% oxygen after BD confirmation. In BD+CO250 and BD+CO500 groups, donor rats inhaled, after BD confirmation, 250 ppm or 500 ppm CO for 120 minutes prior to lung procurement, and orthotopic lung transplantation was performed. The rats were sacrificed 120 minutes after the lung transplantation by exsanguination, and their blood and lung graft samples were obtained. A total of 8 rats fulfilling the criteria were included in each group.

RESULTS

The inhalation decreased the severity of lung injury in grafts from BD donors checked by histological examination. CO pretreatment reversed the aggravation of PaO2/FiO2 in recipients from BD donors. The CO inhalation down-regulated pro-inflammatory cytokines (TNF-alpha, IL-6) along with the increase of anti-inflammatory cytokine (IL-10) in recipient serum, and inhibited the activity of myeloperoxidase in grafts tissue. The inhalation significantly decreased cell apoptosis in lung grafts, inhibiting mRNA and protein expression of intercellular adhesion molecule-1 (ICAM-1) and caspase-3 in lung grafts. Further, the inhalation activated phosphorylation of p38 expression and inhibited phosphorylation of anti-extracellular signal-regulated kinase (ERK) expression in lung grafts. The effects of CO at 500 ppm were greater than those at 250 ppm.

CONCLUSIONS

CO exerts potent protective effects on lung grafts from BD donor, exhibiting anti-inflammatory and anti-apoptosis functions by modulating the mitogen-activated protein kinase (MAPK) signal transduction.

Aerosolized surfactant and dextran for experimental acute respiratory distress syndrome caused by acidified milk in rats

BACKGROUND

Inhibition of pulmonary surfactant by plasma-derived proteins is an important pathogenetic factor of acute respiratory distress syndrome (ARDS). Inhalation of aerosolized surfactant may be suitable for early treatment of ARDS. However, requirement of a high dose is a drawback. Because dextran reverses surfactant inhibition, we examined whether dextran improves the therapeutic effects of aerosolized surfactant in rats with experimental ARDS.

METHODS

Acidified milk (pH 1.8, 1.5 ml kg(-1)) was injected into the trachea of the rats ventilated with pure oxygen using 2.45 kPa peak inspiratory pressure and 0.74 kPa positive end-expiratory pressure. When PaO2 decreased to <13 kPa, the rats were assigned to four groups: control group (n = 8), receiving no material; D-only group (n = 6), receiving aerosolized dextran for 45 min; S-only group (n = 8), receiving aerosolized modified natural surfactant (MNS) for 30 min; and S-plus-D group (n = 9), receiving aerosolized MNS for 30 min followed by aerosolized dextran for 15 min.

RESULTS

In the control group and D-only groups, the mean PaO2 remained at <10 kPa for 180 min. In the S-only and S-plus-D groups, the PaO2 increased to 50 kPa (P < 0.01 vs. untreated). The PaO2 of the surfactant-only group gradually decreased to <17 kPa at 180 min, whereas the PaO2 of the S-plus-D group was maintained at >38 kPa for 180 min (P < 0.01 vs. S-only group).

CONCLUSION

Inhalation of aerosolized dextran potentiates the effects of aerosolized surfactant by prolonging the therapeutic response.

Modified protocols for surfactant therapy in experimental meconium aspiration syndrome

In adult rats with experimental meconium aspiration syndrome, we investigated whether the therapeutic effect of exogenous surfactant was increased by addition of dextran or preceding airway lavage with diluted surfactant. Animals (n = 72) ventilated with pure oxygen were given human meconium suspension (50-75 mg kg(-1)) through the airways. When the PaO(2) had decreased to <20 kPa (mean +/- SD 12 +/- 3.9 kPa), the rats were randomly allocated to ten groups (G). G 6-10 underwent lung lavage with diluted Curosurf (5 mg ml(-1), 20 ml kg(-1)), whereas G 1-5 did not. G 1 and 6 received no additional material through the airways. G 2 and 7 received Curosurf (100 mg kg(-1)), and G 3 and 8 received Curosurf (100 mg kg(-1)) plus dextran (75 mg kg(-1)); G 4 and 9 received Curosurf (200 mg kg(-1)), and G 5 and G 10 received Curosurf (200 mg kg(-1)) plus dextran (75 mg kg(-1)). All rats in G 1 died before 180 min after randomization. In G 2, 3, 6, 7, and 8, the PaO(2) transiently increased to 30-40 kPa. In G 4, 5, 9, and 10, the PaO(2) remained >30 kPa for 180 min. Both airway lavage and supplementation with dextran improved the therapeutic effects of surfactant; however, a large dose (200 mg kg(-1)) was nevertheless required to optimize gas exchange.