Effect of dexmedetomidine on intrapulmonary shunt in patients with sevoflurane maintained during one-lung ventilation: A case-control study.

BACKGROUND: The effects of dexmedetomidine on the circulatory system are complex. It is difficult to predict its effects on intrapulmonary shunts and hypoxic pulmonary vasoconstriction in patients with one-lung ventilation. This study aimed to investigate the effect of dexmedetomidine on intrapulmonary shunt in patients with sevoflurane during one-lung ventilation. METHODS: Forty patients requiring thoracoscopic lobectomy were randomly divided into the dexmedetomidine group (Group D, n = 20) and the normal saline group (Group N, n = 20). The arterial partial pressure of oxygen (PaO2), pulmonary shunt fraction (Qs/Qt), mean end-tidal sevoflurane concentration, mean arterial pressure, and heart rate were compared between the 2 groups at 3 time points: (i) after 5 minutes of two-lung ventilation (T0), (ii) after 30 minutes of one-lung ventilation (OLV) (T1), and (iii) after 45 minutes of OLV (T2). The dosage of sevoflurane from the beginning of OLV to T2 was calculated. RESULTS: There were no significant differences in age, body mass index, and FEV1/FVC between Groups D and N (P > .05). At T0, T1, and T2, the PaO2 levels of Group D and Group N were similar (P > .05), and the PaO2 levels of Group D and Group N decreased after OLV. The Qs/Qt level of Groups D and N were similar at T0 (P > .05), and the level of Groups D and N at T1 and T2 was higher than that at T0. The Qs/Qt of Group D was statistically significantly lower than that of Group N at T1 and T2 (P < .05). CONCLUSION: Compared with the control group, we found that dexmedetomidine can reduce the intrapulmonary shunt fraction and improve the body's status during OLV.

MicroRNA-154/ADAM9 axis inhibits the proliferation, migration and invasion of breast cancer cells.

Breast cancer is the leading cause for cancer-associated mortality in women. Although great progress has been made in the earlier diagnosis and systemic therapy of patients with breast cancer in recent years, recurrence or distant metastasis continue to present major barriers to the successful treatment of breast cancer. Therefore, fully understanding the molecular mechanisms underlying the progression of breast cancer may be critical for the development of effective therapeutic strategies against breast cancer. The aim of the present study was to explore the expression, function and molecular mechanisms of microRNA-154 (miR-154) in human breast cancer. It was demonstrated that miR-154 was significantly downregulated in breast cancer tissue and cell lines. The restoration of miR-154 expression suppressed the proliferation, migration and invasion of breast cancer cells. ADAM metallopeptidase domain 9 (ADAM9) was identified as a novel direct target for miR-154 in breast cancer. It was demonstrated that miR-154 acted as a tumor suppressor in breast cancer by targeting ADAM9. The results of the present study suggest that the restoration of miR-154 expression may be an effective therapeutic strategy for the treatment of breast cancer in the future.

Pathway-related modules involved in the application of sevoflurane or propofol in off-pump coronary artery bypass graft surgery.

Off-pump coronary artery bypass graft (CABG) surgery has recently emerged as a means to avoid the sequelae of extracorporeal circulation, including the whole-body inflammatory response, coagulation disorders and multiple organ dysfunction. At present, gas anesthesia, sevoflurane and intravenous anesthesia and propofol have been widely used during the CABG. To further understand the underlying mechanisms of these anesthetics on the gene level, the present study conducted pathway-related module analysis based on a co-expression network. This was performed in order to identify significant pathways in coronary artery disease patients who had undergone off-pump CABG surgery before and after applying sevoflurane or propofol. A total of 269 and 129 differentially expressed genes were obtained in the sevoflurane and propofol groups, respectively. In total, eight and seven pathways (P<0.05) in the sevoflurane and propofol groups were separately obtained via Kyoto Encyclopedia of Genes and Genome pathway analysis. Finally, eight and seven pathway-related modules in the sevoflurane and propofol groups were obtained, respectively. Furthermore, the mean degree of complement and coagulation cascades pathway-related module in both of the groups was the highest. It was predicted that during the CABG, the anesthetics might activate the complement and coagulation systems in order to possess some cardioprotective properties.

Dexmedetomidine attenuates inflammatory reaction in the lung tissues of septic mice by activating cholinergic anti-inflammatory pathway.

Dexmedetomidine (Dex) is a highly selective α2-adrenergic receptor agonist that is widely used for sedation in intensive care units and in clinical anesthesia. Dex has also been shown to possess anti-inflammatory benefits. However, the underlying mechanism by which Dex relieves the inflammatory reaction in the lung tissues of septic mice has not been fully elucidated. In this study, we aimed to evaluate the protective effects and possible mechanism of Dex on the sepsis-induced lung inflammatory response in mice. Sepsis was induced in mice models through the intraperitoneal injection of lipopolysaccharide (LPS). The preemptive administration of Dex substantially abated sepsis-induced pulmonary edema, pulmonary histopathological changes, and NF-κB p65 activity. The production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) at both the mRNA and protein levels was also reduced. Moreover, these effects were significantly blocked by the α7 nicotinic acetylcholine receptor (α7nAChR) antagonist α-bungarotoxin (α-Bgt). α-Bgt aggravated pulmonary edema and pulmonary histopathological changes, as well as increased NF-κB p65 activity and TNF-α and IL-6 expression at both the mRNA and protein levels. The overall results demonstrate that Dex inhibits the LPS-induced inflammatory reaction in the lung tissues of septic mice partly through the α7nAChR-dependent cholinergic anti-inflammatory pathway.

The role of spleen in the treatment of experimental lipopolysaccharide-induced sepsis with dexmedetomidine.

Dexmedetomidine (Dex), a highly selective α2-adrenergic receptor agonist, has been shown to attenuate systemic inflammatory response induced by lipopolysaccharide (LPS). The protective effects of Dex may reportedly be due to the activation of the α7 nicotinic acetylcholine receptor (α7nAChR)-dependent cholinergic anti-inflammatory pathway. Spleen has been shown to play a pivotal role in the neural cholinergic anti-inflammatory pathway. However, little is known about the specific function of spleen in the protective effects of Dex against sepsis. To investigate the role of spleen in the treatment of Dex against sepsis, we studied the effects of preemptive administration of Dex to septic mice on the NF-κB p65 activation and downstream pro-inflammatory cytokine expression in the spleen. Our results provided evidence that Dex treatment attenuated LPS-activated NF-κB p65 activation, as well as the production of tumor necrosis factor-α, interleukin-6, and interleukin-1ß at the level of both mRNA and protein in spleen. Consequently, serum concentrations of these cytokines decreased. Conversely, preemptive injection of α-bungarotoxin, a selective α7nAChR antagonist, reversed these effects of Dex. Our findings indicated that spleen played a critical role in the protective effects of Dex against sepsis and provided further insight into the anti-inflammatory mechanisms of Dex.

High voltage pulser with a fast fall-time for plasma immersion ion implantation.

A novel high voltage (HV) modulator that offers a short fall time to minimize sputtering effects and allow more precise control of the incident ion fluence in plasma immersion ion implantation is described. The use of 36 insulated-gate bipolar transistors in the 30 kV hard-tube pulser reduces the HV fall time to 3.5 µs, compared to a fall time of 80 µs if a pull-down resister is used. The voltage balance is achieved by a voltage-balancing resistor, clamped capacitance, and the synchronization of drive signals. Compared to the traditional method employing a pull-down resister or an additional hard tube, our design consumes less power and is more economical and reliable.

Novel plasma immersion ion implantation and deposition hardware and technique based on high power pulsed magnetron discharge.

A novel plasma immersion ion implantation technique based on high power pulsed magnetron sputtering (HPPMS) discharge that can produce a high density metal plasma is described. The metal plasma is clean and does not suffer from contamination from macroparticles, and the process can be readily scaled up for industrial production. The hardware, working principle, and operation modes are described. A matching circuit is developed to modulate the high-voltage and HPPMS pulses to enable operation under different modes such as simultaneous implantation and deposition, pure implantation, and selective implantation. To demonstrate the efficacy of the system and technique, CrN films with a smooth and dense surface without macroparticles were produced. An excellent adhesion with a critical load of 59.9 N is achieved for the pure implantation mode.

Hybrid radio-frequency/direct-current plasma-enhanced chemical vapor deposition system for deposition on inner surfaces of polyethylene terephthalate bottles.

A hybrid radio-frequency (rf)/direct-current (dc) system has been developed to control the biasing effects during deposition of diamondlike carbon (DLC) films onto the inner wall of polyethylene terephthalate (PET) bottles. An additional dc bias is coupled to the rf electrode to produce the effect of equivalent rf self-biasing. This allows more flexible control of the deposition of the DLC films which are intended to improve the gas barrier characteristics. The experimental results demonstrate that the additional dc bias improves the adhesion strength between the DLC film and PET, although the enhancement in the gas barrier properties is not significantly larger compared to the one without dc bias. The apparatus and methodology have practical importance in the food and beverage industry.

Direct coupling of pulsed radio frequency and pulsed high power in novel pulsed power system for plasma immersion ion implantation.

A novel power supply system that directly couples pulsed high voltage (HV) pulses and pulsed 13.56 MHz radio frequency (rf) has been developed for plasma processes. In this system, the sample holder is connected to both the rf generator and HV modulator. The coupling circuit in the hybrid system is composed of individual matching units, low pass filters, and voltage clamping units. This ensures the safe operation of the rf system even when the HV is on. The PSPICE software is utilized to optimize the design of circuits. The system can be operated in two modes. The pulsed rf discharge may serve as either the seed plasma source for glow discharge or high-density plasma source for plasma immersion ion implantation (PIII). The pulsed high-voltage glow discharge is induced when a rf pulse with a short duration or a larger time interval between the rf and HV pulses is used. Conventional PIII can also be achieved. Experiments conducted on the new system confirm steady and safe operation.