Esketamine versus Sufentanil Applied Prior to Placement of Suspension Laryngoscope

OBJECTIVE

In laryngeal microsurgery, the insertion of the suspension laryngoscope is a strong stimulus that may cause hemodynamic fluctuations and adverse cardiovascular events. The purpose of this study was to compare the effect of preemptive treatment with esketamine and sufentanil on maintaining hemodynamics and reducing the occurrence of adverse cardiovascular events during the insertion of suspension laryngoscope.

METHODS

In this double-blind randomized controlled trial, patients undergoing general anesthesia for laryngeal microsurgery were randomly assigned (1:1) to esketamine 0.5 mg kg-1 (esketamine group) and sufentanyl 0.125 μg kg-1 (sufentanil group) before inserting the laryngoscope, respectively.

RESULTS

During the insertion of suspension laryngoscope, the incidence of bradycardia (HR < 60 beats/min) was 39.3% (22/56) in esketamine group, lower than 60.0% (33/55) in sufentanil group (odds ratio [OR], 2.32 [95% CI, 1.11-5.08]; p = 0.029). The incidence of hypotension (MAP <65 mmHg) was 33.9% (19/56) in esketamine group, lower than 56.4% (31/55) in sufentanil group (odds ratio [OR], 2.52 [95% CI, 1.91-5.27]; p = 0.018). The frequency of hypotension in esketamine group was lower than that in sufentanil group (0.36 ± 0.52 vs. 0.56 ± 0.50, p = 0.035). The time-weighted average of HR dropping above 30% of baseline was smaller in esketamine group than in sufentanil group (0.52 ± 2.06 vs. 1.08 ± 2.77, p = 0.006).

CONCLUSIONS

These findings showed that compared with preemptive treatment of sufentanil (0.125 μg kg-1 ), esketamine (0.5 mg kg-1 ) was effective in reducing the incidence of cardiovascular adverse events, including bradycardia and hypotension induced by the insertion of suspension laryngoscope during the laryngeal microsurgery.

LEVEL OF EVIDENCE

2 Laryngoscope, 133:3021-3027, 2023.

Repeated neonatal isoflurane exposure facilitated stress-related fear extinction impairment in male mice and was associated with ΔFosB accumulation in the basolateral amygdala and the hippocampal dentate gyrus

Volatile anesthetics elicit neurodevelopmental toxicity in rodents and primates and lead to more exaggerated anxiety-like behavior in response to future stress. Anxiety and fear are closely correlated and maladaptive fear-associated learning is regarded as the core mechanism underlying anxiety-related disorders. However, little is known about the interaction between early-life anesthetic exposure and future stress and the accompanying effect on fear-associated learning. In the present study, we evaluated the alterations in fear-associated learning (fear acquisition and extinction) occurring in mice receiving repeated neonatal isoflurane exposure and chronic variable stress (CVS) successively through a series of fear conditioning, fear reinforcing, and fear extinction paradigms. The corticosterone (CORT) response during CVS and the immunohistochemical levels of ΔFosB and c-Fos expression in the basolateral amygdala (BLA) and the hippocampal dentate gyrus (DG) after the extinction retrieval test were also investigated. The results showed that neonatal isoflurane exposure could increase CORT levels following the first diurnal CVS procedure, but not after completion of the whole CVS paradigm. Neonatal isoflurane exposure exerted a repressive effect on fear acquisition, in contrast to that seen with CVS. Neonatal isoflurane exposure and CVS both exerted suppressive effects on fear extinction and there was a significant synergy between them. Furthermore, neonatal isoflurane exposure facilitated CVS-mediated ΔFosB accumulation in the BLA and the hippocampal DG, which may have been responsible for c-Fos expression deficits and fear extinction impairment. Collectively, these findings contribute to the understanding of the interaction between early-life anesthetic exposure and future stress, as well as the accompanying behavioral alterations.

Efficacy and safety of remimazolam besylate in bronchoscopy for adults: A multicenter, randomized, double-blind, positive-controlled clinical study

Background: With the development of fiberoptic bronchoscopy in the diagnosis and treatment of various pulmonary diseases, the anesthesia/sedation requirements are becoming more demanding, posing great challenges for patient safety while ensuring a smooth examination/surgery process. Remimazolam, a brand-new ultra-short-acting anesthetic, may compensate for the shortcomings of current anesthetic/sedation strategies in bronchoscopy.

Methods: This study was a prospective, multicenter, randomized, double-blind, parallel positive controlled phase 3 clinical trial. Subjects were randomized to receive 0.2 mg/kg remimazolam besylate or 2 mg/kg propofol during bronchoscopy to evaluate the efficacy and safety of remimazolam.

Results: A total of 154 subjects were successfully sedated in both the remimazolam group and the propofol group, with a success rate of 99.4% (95%CI of the adjusted difference −6.7 × 10%–6% to −5.1 × 10%–6%). The sedative effect of remimazolam was noninferior to that of propofol based on the prespecified noninferiority margin of −5%. Compared with the propofol group, the time of loss of consciousness in the remimazolam group (median 61 vs. 48s, p < 0.001), the time from the end of study drug administration to complete awakening (median 17.60 vs. 12.80 min, p < 0.001), the time from the end of bronchoscopy to complete awakening (median 11.00 vs. 7.00 min, p < 0.001), the time from the end of study drug administration to removal of monitoring (median 19.50 vs. 14.50 min, p < 0.001), and the time from the end of bronchoscopy to removal of monitoring (median 12.70 vs. 8.60 min, p < 0.001) were slightly longer. The incidence of Adverse Events in the remimazolam group and the propofol group (74.8% vs. 77.4%, p = 0.59) was not statistically significant, and none of them had Serious Adverse Events. The incidence of hypotension (13.5% vs. 29.7%, p < 0.001), hypotension requiring treatment (1.9% vs. 7.7%, p = 0.017), and injection pain (0.6% vs. 16.8%, p < 0.001) were significantly lower in the remimazolam group than in the propofol group.

Conclusion: Moderate sedation with 0.2 mg/kg remimazolam besylate is effective and safe during bronchoscopy. The incidence of hypotension and injection pain was less than with propofol, but the time to loss of consciousness and recovery were slightly longer.

Clinical Trial Registration:clinicaltrials.gov, ChiCTR2000039753

Association of Nap Frequency With Hypertension or Ischemic Stroke Supported by Prospective Cohort Data and Mendelian Randomization in Predominantly Middle-Aged European Subjects

BACKGROUND AND PURPOSE

The aim of this study was to investigate the association between daytime napping frequency and the incidence of essential hypertension or stroke as well as to validate causality in this relationship via Mendelian randomization (MR).

METHODS

We conducted Cox regression analysis on 358 451 participants free of hypertension or stroke from UK Biobank. To validate the results of the observational analysis, we conducted a 2-sample MR for daytime napping frequency (123 single-nucleotide polymorphisms) with essential hypertension in FinnGen Biobank, stroke, and ischemic stroke in MEGASTROKE consortium and performed a corresponding 1-sample MR on the UK Biobank data.

RESULTS

Compared with never napping, usually napping was associated with a higher risk of essential hypertension (hazard ratio, 1.12 [95% CI, 1.08-1.17]), stroke (hazard ratio, 1.24 [95% CI, 1.10-1.39], and ischemic stroke (hazard ratio, 1.20 [95% CI, 1.05-1.36]) in our prospective observational analysis. Both the 1-sample and 2-sample MR results indicated that increased daytime napping frequency was likely to be a potential causal risk factor for essential hypertension in FinnGEN (odds ratio, 1.43 [95% CI, 1.06-1.92]) and UK Biobank (odds ratio, 1.40 [95% CI, 1.28-1.58]). The 2-sample MR results supported the potential causal effect of nap frequency on ischemic stroke in MEGASTROKE (odds ratio, 1.29 [95% CI, 1.04-1.62]).

CONCLUSIONS

Prospective observational and MR analyses provided evidence that increased daytime nap frequency may represent a potential causal risk factor for essential hypertension. The potential causal association of increased nap frequency with ischemic stroke was supported by 2-sample MR and prospective observational results.

A multicenter survey of perioperative anxiety in China: Pre- and postoperative associations

OBJECTIVES

To describe patient characteristics associated with preoperative anxiety and subsequently assess the relationship between preoperative anxiety and postoperative anxiety, pain, sleep quality, nausea and vomiting.

METHODS

The study collected data from patients undergoing elective operation from 12 hospitals in China. The State-Trait Anxiety Inventory (STAI) and the Athens Insomnia Scale (AIS) were used to assess anxiety and sleep quality before surgery. Evaluations of anxiety, pain, sleep quality, nausea and vomiting were quantified using the Visual Analogue Scale on postoperative days 1 and 2.

RESULTS

Data from 997 patients were analyzed. Preoperatively, 258 (25.9%) patients had high anxiety (STAI-State>44). Multivariate analyses showed a significant relationship between high anxiety and female gender (OR: 1.66, 95% CI: 1.08-2.57, p = 0.02), highly invasive surgery (OR: 2.29, 95% CI: 1.29-4.06, p = 0.005), higher trait anxiety (OR: 1.24, 95% CI: 1.20-1.28, p < 0.001) and insomnia (AIS ≥ 6, OR: 1.79, 95% CI: 1.17-2.76, p = 0.008). Preoperative anxiety demonstrated a negative correlation with postoperative anxiety following highly invasive surgery; this became a positive relationship following less invasive surgery. Preoperative anxiety was also positively related to postoperative pain and poor sleep quality. The correlation between preoperative anxiety and postoperative nausea and vomiting was not statistically significant.

CONCLUSION

Female gender, highly invasive surgery, higher trait anxiety and insomnia are independent risk factors for high preoperative anxiety. Surgical invasiveness influences association between pre- and postoperative anxiety. Higher preoperative anxiety is related to poorer sleep quality and more severe pain postoperatively.

Effects of a Preoperative Carbohydrate-Rich Drink Before Ambulatory Surgery: A Randomized Controlled, Double-Blinded Study

Background

The guidelines recommend oral carbohydrates up to 2 hr before elective surgery. The objective of this study was to explore the safety and feasibility of preoperative carbohydrate drink in patients undergoing ambulatory surgery.

Material/Methods

Patients undergoing ambulatory surgery under general anesthesia were enrolled. They were fasted from midnight and randomly assigned to a study group (200 mL of a carbohydrate beverage) or the control group (pure water) and received the assigned drink 2 hr before surgery. Bedside ultrasonography was performed to monitor gastric emptying at T₀ (before liquid intake), T₁ (5 min after intake), T₂ (1 hr after intake), and T₃ (2 hr after intake). Subjective feelings of thirst, hunger, anxiety, and fatigue were assessed 1 hr after liquid intake using the visual analogue scale (VAS).

Results

In both groups, gastric antrum cross-sectional area, gastric content volume, and weight-corrected gastric content volume increased at T₁ and returned to baseline at T₃. These parameters were significantly higher in the study group at T₂ (6.28±1.38 vs. 4.98±0.78, 67.22±29.49 vs. 49.04±15.4, 1.10±0.51 vs. 0.85±0.37, P<0.05). Thirst and hunger VAS scores were reduced in both groups. The study group suffered significantly less hunger (28.44±10.41 vs. 36.03±14.42, P<0.05). Blood electrolytes (sodium, potassium, calcium) and glucose concentration levels were similar in both groups at T₂. No gastric regurgitation or pulmonary aspiration was recorded.

Conclusions

Administration of 200 mL of oral carbohydrate beverage 2 hr before ambulatory surgery is safe, effective, and can be used for preoperative management of fasting patients.

Pain management after ambulatory surgery: a prospective, multicenter, randomized, double-blinded parallel controlled trial comparing nalbuphine and tramadol

Background

Postoperative pain in ambulatory surgery is a multifactorial issue affecting patient satisfaction, time of discharge, and rehospitalization. This study evaluated the efficacy and safety of nalbuphine for the treatment of postoperative pain after ambulatory surgery, relative to tramadol.

Methods

This multi-center, randomized, double blind, and controlled study was conducted at 10 centers. In accordance with the inclusion criteria, 492 ambulatory surgery patients were recruited. These patients had moderate to severe pain after ambulatory surgery, with a visual analogue scale (VAS) score > 3 cm. They were randomly divided into an experimental (n = 248) or control (n = 244) group and treated for analgesia with 0.2 mg/kg of nalbuphine or 2 mg/kg of tramadol, respectively. VAS scores, adverse events, and vital signs of the patients were recorded before administration (baseline; T₁); and 30 min (T₂), 2 h (T₃), 4 h (T₄), and 6 h (T₅) after administration of analgesia. A decrease in pain intensity of more than 25% compared with the baseline was used as an indicator of analgesic efficacy. The experimental and control groups were compared with regard to this indicator of efficacy at each timepoint.

Results

The VAS scores of the experimental and control groups were statistically comparable at timepoints T₁-T₄. At T₅, the VAS scores of the experimental group were significantly lower than that of the control. The pain intensity was significantly higher in the experimental group compared with the control at T₂ and T₃. Adverse events and vital signs were similar for the two groups at each timepoint.

Conclusions

Nalbuphine can provide effective and safe pain relief in patients after ambulatory surgery.

Trial registration

The registration number is ChiCTR-IOR-16010032, the date of registration was 2016-11-28.

Rac1 relieves neuronal injury induced by oxygenglucose deprivation and re-oxygenation via regulation of mitochondrial biogenesis and function

Certain microRNAs (miRNAs) can function as neuroprotective factors after reperfusion/ischemia brain injury. miRNA-142-3p can participate in the occurrence and development of tumors and myocardial ischemic injury by negatively regulating the activity of Rac1, but it remains unclear whether miRNA-142-3p also participates in cerebral ischemia/reperfusion injury. In this study, a model of oxygen-glucose deprivation/re-oxygenation in primary cortical neurons was established and the neurons were transfected with miR-142-3p agomirs or miR-142-3p antagomirs. miR-142-3p expression was down-regulated in neurons when exposed to oxygen-glucose deprivation/re-oxygenation. Over-expression of miR-142-3p using its agomir remarkably promoted cell death and apoptosis induced by oxygen-glucose deprivation/re-oxygenation and improved mitochondrial biogenesis and function, including the expression of peroxisome proliferator-activated receptor-γ coactivator-1α, mitochondrial transcription factor A, and nuclear respiratory factor 1. However, the opposite effects were produced if miR-142-3p was inhibited. Luciferase reporter assays verified that Rac Family Small GTPase 1 (Rac1) was a target gene of miR-142-3p. Over-expressed miR-142-3p inhibited NOX2 activity and expression of Rac1 and Rac1-GTPase (its activated form). miR-142-3p antagomirs had opposite effects after oxygen-glucose deprivation/re-oxygenation. Our results indicate that miR-142-3p down-regulates the expression and activation of Rac1, regulates mitochondrial biogenesis and function, and inhibits oxygen-glucose deprivation damage, thus exerting a neuroprotective effect. The experiments were approved by the Committee of Experimental Animal Use and Care of Central South University, China (approval No. 201703346) on March 7, 2017.

MicroRNA-7a ameliorates neuropathic pain in a rat model of spinal nerve ligation via the neurofilament light polypeptide-dependent signal transducer and activator of transcription signaling pathway

Neuropathic pain is a type of chronic pain induced by either central or peripheral nerve injury. MicroRNAs have been recently linked to many diseases, including neuropathic pain. However, the role of miR-7a in neuropathic pain still remains elusive. Thus, we aim to investigate the effects of miR-7a on neuropathic pain based on the spinal nerve ligation rat model. After establishment of spinal nerve ligation rat models, rats were infected with adeno-associated virus-neurofilament light polypeptide, adeno-associated virus-miR-7a or treated with metformin. The paw withdrawal threshold and paw withdrawal latency were assessed afterward, and the expression of miR-7a and neurofilament light polypeptide as well as their interaction was determined. Subsequently, miR-7a was overexpressed or silenced in dorsal root ganglion cells to investigate the role of miR-7a in neuropathic pain. Furthermore, the regulatory effect of neurofilament light polypeptide on neuropathic pain was detected using plasmid overexpressing neurofilament light polypeptide. Spinal nerve ligation rat model exhibited upregulation of neurofilament light polypeptide but downregulation of miR-7a. In addition, neurofilament light polypeptide accumulation or miR-7a inhibition decreased paw withdrawal threshold and paw withdrawal latency. Then, neurofilament light polypeptide accumulation or miR-7a inhibition was observed to increase the phosphorylation level of signal transducer and activator of transcription. miR-7a was found to directly target neurofilament light polypeptide and downregulate neurofilament light polypeptide. In addition, inhibiting the signal transducer and activator of transcription signaling pathway was also revealed to increase paw withdrawal threshold and paw withdrawal latency. Collectively, our study demonstrated that miR-7a ameliorated neuropathic pain via blocking the signal transducer and activator of transcription signaling pathway by repressing neurofilament light polypeptide. These findings, if taken further, can be of important clinical significance in treating patients with neuropathic pain.

Inhibition of CD38/Cyclic ADP-ribose Pathway Protects Rats against Ropivacaine-induced Convulsion

BACKGROUND

The CD38/cyclic ADP-ribose (cADPR) pathway plays a role in various central nervous system diseases and in morphine tolerance, but its role in local anesthetic intoxication is unknown. The aim of this study was to determine the role of the CD38/cADPR pathway in ropivacaine-induced convulsion.

METHODS

Forty male Sprague-Dawley rats were randomly divided into five groups (n = 8 per group): sham group, ropivacaine group, ropivacaine+8-Br-cADPR (5 nmol) group, ropivacaine+8-Br-cADPR (10 nmol) group, and ropivacaine+8-Br-cADPR (20 nmol) group (no rats died). Rats were intracerebroventricularly injected with normal saline or 8-Br-cADPR 30 min before receiving an intraperitoneal injection of ropivacaine. Electroencephalography and convulsion behavior scores were recorded. The hippocampus was harvested from each group and subjected to nicotinamide adenine dinucleotide and cADPR assays, Western blotting analysis, and malondialdehyde (MDA) and superoxide dismutase (SOD) assays.

RESULTS

Intraperitoneal injection of ropivacaine (33.8 mg/kg) induced convulsions in rats. CD38 and cADPR levels increased significantly following ropivacaine-induced convulsion (P = 0.031 and 0.020, respectively, compared with the sham group). Intraventricular injection of 8-Br-cADPR (5, 10, and 20 nmol) significantly prolonged convulsion latency (P = 0.037, 0.034, and 0.000, respectively), reduced convulsion duration (P = 0.005, 0.005, and 0.005, respectively), and reduced convulsion behavior scores (P = 0.015, 0.015, and 0.000, respectively). Intraventricular injection of 8-Br-cADPR (10 nmol) also increased the B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X protein ratio (P = 0.044) and reduced cleaved Caspase 3/Caspase 3 ratio, inducible nitric oxide synthase, MDA and SOD levels (P = 0.014, 0.044, 0.001, and 0.010, respectively) compared with the ropivacaine group.

CONCLUSIONS

The CD38/cADPR pathway is activated in ropivacaine-induced convulsion. Inhibiting this pathway alleviates ropivacaine-induced convulsion and protects the brain from apoptosis and oxidative stress.

Structural responses of metallic glasses under neutron irradiation

Seeking nuclear materials that possess a high resistance to particle irradiation damage is a long-standing issue. Permanent defects, induced by irradiation, are primary structural changes, the accumulation of which will lead to structural damage and performance degradation in crystalline materials served in nuclear plants. In this work, structural responses of neutron irradiation in metallic glasses (MGs) have been investigated by making a series of experimental measurements, coupled with simulations in ZrCu amorphous alloys. It is found that, compared with crystalline alloys, MGs have some specific structural responses to neutron irradiation. Although neutron irradiation can induce transient vacancy-like defects in MGs, they are fully annihilated after structural relaxation by rearrangement of free volumes. In addition, the rearrangement of free volumes depends strongly on constituent elements. In particular, the change in free volumes occurs around the Zr atoms, rather than the Cu centers. This implies that there is a feasible strategy for identifying glassy materials with high structural stability against neutron irradiation by tailoring the microstructures, the systems, or the compositions in alloys. This work will shed light on the development of materials with high irradiation resistance.

[Application of chromosomal microarray analysis for fetuses with talipes equinovarus]

OBJECTIVE

To investigate the application of fetuses with talipes equinovarus(TE)using chromosomal microarray analysis(CMA)technology.

METHODS

From May 2012 to June 2015, 54 fetuses were found with TE and with or without other structural anomalies by prenatal ultrasound. Karyotyping was taking for them all, and the fetuses with normal karyotypes took another CMA test. The data were analyzed with CHAS software. Finally all the cases were followed up to know about their pregnancy outcomes.

RESULTS

One of the 54 cases was detected with abnormal karyotype which was trisomy 18(2%, 1/54). CMA was undertaken to the remaining fetuses, they were divided into 2 groups, including isolated TE group(n= 38)and complex TE group(n=15). The detection rate of clinical significant copy number variations(CNV)by CMA was 11%(6/53), while isolated and complex TE group were 5%(2/38)and 4/15, respectively(P= 0.047). Of the 53 cases, 51 cases were successfully followed up. Eleven cases were found without TE after birth, and the false positive rate(FPR)of TE was 22%(11/51).

CONCLUSIONS

Whole-genome high-resolution CMA increased the detection rate by 11% in fetuses with TE. With the FPR and the detection rate of the clinical significant CNV of 2 groups, whole-genome CMA could be recommended to the fetuses with complex TE group but normal karyotypes. A series of ultrasonic tests should be suggested to the isolate TE group, while with the abnormal ultrasound, fetuses would be suggested to have CMA test for decreasing the rates of invasive prenatal diagnosis and FPR.

Role of platelet function and platelet membrane glycoproteins in children with primary immune thrombocytopenia

The aim of the present study was to examine and understand changes in platelet functions prior to and after the treatment of primary immune thrombocytopenia (ITP) in children. An automatic hematology analyzer and whole blood flow cytometry were used to detect immature platelet fraction (IPF), IPC and membrane glycoproteins (CD62p, PAC-1 and CD42b) in ITP children (ITP group), children with complete response after ITP treatment (ITP-CR group) and children with elective surgery (normal control group). The results showed that, levels of platelet count (PLT) and plateletcrit in the ITP group were lower alhtough the levels of mean platelet volume, platelet distribution width and platelet-large cell ratio (P-LCR) were higher than those in the normal control and ITP-CR groups. PLT in the ITP-CR group was lower than that in the normal controls. Additionally, IPF% was higher in the normal control and ITP-CR groups, IPC was lower in the ITP group compared to the normal control and ITP-CR groups. Furthermore, prior to ADP activation, the expression levels of CD62p, PAC-1 and CD42b in the ITP group were lower in ITP group than those in the normal control and ITP-CR groups. The expression level of PAC-1 was lower in the ITP-CR and normal control groups. No differences were identified in CD62p and CD42b expression levels. Following ATP activation, CD62p, PAC-1 and CD42b expression in the ITP group was lower than that in the normal control and ITP-CR groups. PAC-1 expression was lower while CD62p expression was higher in the ITP-CR group compared to the normal control group. In conclusion, the activation of platelets in ITP children was low. Decreased platelet function, platelet parameters and platelet glycoproteins may be used as markers for monitoring the treatment efficacy in ITP children.

Effect of ATRA on the expression of HOXA5 gene in K562 cells and its relationship with cell cycle and apoptosis

Leukemia is the most common malignant disease in children with high incidence and mortality rates, and a poor treatment effect. The aim of the present study was to examine the changes in the expression of homeobox (Hox) A5 gene and its relationship with cell cycle and apoptosis through the intervention of human K562 myeloid leukemia cell line by all-trans retinoic acid (ATRA), to analyze the role of HOXA5 in the pathogenesis and development process of myeloid leukemia. The optimal concentration of ATRA to be used with K562 cells was determined using a cell counting kit-8 (CCK-8). After 24, 72 and 48 h following treatment of K562 cells with 10 µmol/l ATRA, cell cycle events and apoptosis were measured using flow cytometry. HOXA5 mRNA and protein expression in K562 cells was assessed by RT-PCR and western blot analysis, and the relationship between HOXA5 expression and cell cycle and apoptosis was analyzed. The HOXA5 mRNA and protein expression levels were increased following treatment with ATRA in K562 cells. Apoptosis was increased significantly. The cell cycle was inhibited in G0/G1 phase. Cell proliferation was also inhibited. HOXA5 mRNA and protein expression rates positively correlated with cell apoptosis and the increased percentage and cell cycle of the G0/G1 phase. However, HOXA5 negatively correlated with the reduced percentage of S stage. In conclusion, the expression of HOXA5 in cells was increased following treatment with ATRA in K562 cells, in a time-dependent manner. Additionally, ATRA may inhibit the proliferation of K562 cells and promote apoptosis by upregulating the HOXA5 mRNA and protein expression.

Effect of silencing HOXA5 gene expression using RNA interference on cell cycle and apoptosis in Jurkat cells

Acute lymphocytic leukemia (ALL) is a common malignant tumor with a high morbidity rate among children, accounting for approximately 80% of leukemia cases. Although there have been improvements in the treatment of patients frequent relapse lead to a poor prognosis. The aim of the present study was to determine whether HOXA5 may be used as a target for gene therapy in leukemia in order to provide a new treatment. Mononuclear cells were extracted from the bone marrow according to the clinical research aims. After testing for ALL in the acute stage, the relative mRNA and protein expression of HOXA5 was detected in the ALL remission groups (n=25 cases per group) and the control group [n=20 cases, immune thrombocytopenia (ITP)]. Gene silencing by RNA interference (RNAi) was used to investigate the effect of silencing HOXA5 after small interfering RNA (siRNA) transfection to Jurkat cells. The HOXA5-specific siRNA was transfected to Jurkat cells using lipofectamine. The experiment was divided into the experimental group (liposomal transfection of HOXA5 targeting siRNA), the negative control group (liposomal transfection of cells with negative control siRNA) and the control group (plus an equal amount of cells and culture media only). Western blotting and quantitative fluorescent polymerase chain reaction (QF‑PCR) were used to detect the relative HOXA5 mRNA expression and protein distribution in each cell group. Cell distribution in the cell cycle and the rate of cells undergoing apoptosis were determined using flow cytometry. The expression of HOXA5 at the mRNA and protein levels in the acute phase of ALL was significantly higher than that in ALL in the remission and control groups. In cells transfected with HOXA5-specific siRNA, the expression of HOXA5 at the mRNA and protein levels decreased significantly (P<0.05). The distribution of cells in the cell cycle was also altered. Specifically, more cells were present in the G0/G1 phase compared to the S phase (P<0.05). In addition, the apoptotic rate was significantly higher in cells transfected with HOXA5‑specific siRNA (P<0.05). In conclusion, high expression levels of HOXA5 mRNA and protein in children with ALL indicate that HOXA5 is closely associated with childhood ALL. In addition, HOXA5-specific siRNA effectively silences HOXA5 gene expression and induces apoptosis and cell-cycle arrest in Jurkat cells, thus inhibiting cell proliferation.

Swimming exercise ameliorates neurocognitive impairment induced by neonatal exposure to isoflurane and enhances hippocampal histone acetylation in mice

Isoflurane-induced neurocognitive impairment in the developing rodent brain is well documented, and regular physical exercise has been demonstrated to be a viable intervention for some types of neurocognitive impairment. This study was designed to investigate the potential protective effect of swimming exercise on both neurocognitive impairment caused by repeated neonatal exposure to isoflurane and the underlying molecular mechanism. Mice received 0.75% isoflurane exposures for 4h on postnatal days 7, 8, and 9. From the third month after anesthesia, the mice were subjected to regular swimming exercise for 4weeks, followed by a contextual fear condition (CFC) trial. We found that repeated neonatal exposure to isoflurane reduced freezing behavior during CFC testing and deregulated hippocampal histone H4K12 acetylation. Conversely, mice subjected to regular swimming exercise showed enhanced hippocampal H3K9, H4K5, and H4K12 acetylation levels, increased numbers of c-Fos-positive cells 1h after CFC training, and less isoflurane-induced memory impairment. We also observed increases in histone acetylation and of cAMP-response element-binding protein (CREB)-binding protein (CBP) during the swimming exercise program. The results suggest that neonatal isoflurane exposure-induced memory impairment was associated with dysregulation of H4K12 acetylation, which may lead to less hippocampal activation following learning tasks. Swimming exercise was associated with enhanced hippocampal histone acetylation and CBP expression. Exercise most likely ameliorated isoflurane-induced memory impairment by enhancing hippocampal histone acetylation and activating more neuron cells during memory formation.

Platelet parameters and expression of platelet membrane glycoprotein in childhood acute lymphoblastic leukemia

Platelet activation and functional changes were investigated in acute lymphoblastic leukemia (ALL) to provide the basis for early diagnosis and evaluation of curative effect. Platelet parameters, immature platelet fraction (IPF%), immature platelet count (IPC), P-selectin (CD62p) (PAC-1) expression were detected in ALL, ALL-complete remission-induced (CR1), and normal groups with an automatic blood cell analyzer and flow cytometer. CD62p and PAC-1 were higher in the ALL group before adenosine-5-diphosphate (ADP) activation than in the normal group (P < 0.05); PAC-1 expression was higher and lower in the ALL-CR1 group than in normal and ALL groups (P < 0.05), respectively. CD62p and PAC-1 expression was lower in the ALL group than in the normal group after ADP activation (P < 0.05); PAC-1 expression was lower and higher in the ALL-CR1 group than in normal and ALL groups, respectively (P < 0.05). Platelet count (PLT), mean platelet volume (MPV), platelet hematocrit (PCT), and platelet distribution width (PDW) were lower in the ALL group than in the ALL-CR1 group (P < 0.05). PLT, MPV, and PCT did not differ between the ALL-CR1 group and the normal group (P > 0.05). PDW did not differ statistically among all groups (P > 0.05). IPF% and IPC values were higher and lower in the ALL group than in normal and ALL-CR1 groups (P < 0.05), respectively. These did not differ significantly between the normal group and the ALL-CR1 group (P > 0.05). Therefore, ALL patients demonstrate platelet activation and platelet dysfunction; platelet parameters and membrane glycoprotein expression can be used to evaluate the effect of ALL.

Multiple functions of the first EGF domain in matrilin-3: Secretion and endoplasmic reticulum stress

Mutations in matrilin-3 are associated with common skeletal diseases, such as hand osteoarthritis (HOA), as well as rare chondrodysplasias, such as multiple epiphyseal dysplasia (MED) and spondyloepimetaphyseal dysplasia (SEMD). In the present study, we constructed the mutations R116W [at the von Willebrand factor, type A (vWFA) domain], T298M [at the first epidermal growth factor (EGF) domain] and C299S (at the first EGF domain), according to the mouse sequence, which are associated with human MED, HOA and SEMD, respectively, by overlap extension PCR and inserted them into an expression vector (pcDNA3.1/v5-His). We transfected these contructs into the COS-1 or MCT cells, and the results revealed that the HOA-related matrilin-3 mutation (T298M) leads to a high expression level of growth arrest DNA damage-inducible gene 153 (GADD153, also known as CHOP; an endoplasmic reticulum stress marker), as shown by western blot analysis and does not significantly affect protein secretion, as shown by immunofluorescence staining; however, osteochondroplasia, i.e., MED-related (R116W) and SEMD-related (C299S) mutations lead to both high levels of GADD153 expression and protein trafficking into the cytoplasm and form multiple vacuoles in cells, which in turn leads to insufficient protein secretion.

Propagation characteristics of a focused laser beam in a strontium barium niobate photorefractive crystal under reverse external electric field

The propagation characteristics of a focused laser beam in a SBN:75 photorefractive crystal strongly depend on the signal-to-background intensity ratio (R=I_s/I_b) under reverse external electric field. In the range 20>R>0.05, the laser beam shows enhanced self-defocusing behavior with increasing external electric field, while it shows self-focusing in the range 0.03>R>0.01. Spatial solitons are observed under a suitable reverse external electric field for R=0.025. A theoretical model is proposed to explain the experimental observations, which suggest a new type of soliton formation due to "enhancement" not "screening" of the external electrical field.

Repression of contexual fear memory induced by isoflurane is accompanied by reduction in histone acetylation and rescued by sodium butyrate

BACKGROUND

Isoflurane produces amnesia in mice during contextual fear conditioning (CFC) trials. Histone acetylation is a form of chromatin modification involved in the transcriptional regulation underlying memory formation. We investigated whether isoflurane-induced repression of contextual fear memory is related to altered histone acetylation in the hippocampus, and whether it can be rescued by the histone deacetylases inhibitor sodium butyrate (SB).

METHODS

Adult C57BL/6 mice were chronically given intraperitoneal injections of SB or vehicle for 28 days. Immediately before CFC training, the mice were exposed to isoflurane or air for 30 min and CFC testing was performed the next day. Hippocampal histone acetylation was analysed 1 h after CFC training. c-Fos, an immediate early gene (IEG) suggested to participate in learning and memory formation, was also investigated at the same timepoint.

RESULTS

Mice exposed to isoflurane showed a reduction in freezing time during the CFC test. These mice also exhibited reduced hippocampal H3K14, H4K5, and H4K12 acetylation 1 h after CFC training, and also decreased c-Fos expression. All of these changes were attenuated in isoflurane-exposed mice that were chronically treated with SB.

CONCLUSIONS

Isoflurane suppresses histone acetylation and down-regulates c-Fos gene expression in CA1 of the hippocampus after CFC training. These changes are associated with isoflurane-induced amnesia. The HDAC inhibitor SB prevented repressed contextual fear memory, presumably by promoting histone acetylation and histone acetylation-mediated gene expression in response to CFC training.

Suppressing SNAP-25 and reversing glial glutamate transporters relieves neuropathic pain in rats by ameliorating imbalanced neurotransmission

BACKGROUND

Neuropathic pain results from a lesion or disease affecting the somatosensory system at either the peripheral or central level. The transmission of nociception within the central nervous system is subject to modulation by release and reuptake of neurotransmitters, which maintain a dynamic balance through the assembly and disassembly of the SNARE complex as well as a series of neurotransmitter transporters (inhibitory GABA transporters GAT and excitatory glutamate transporters GT). Neuronal hyper-excitability or defected inhibition involved in neuropathic pain is one of the outcomes caused by imbalanced neurotransmission. SNAP-25, which is one of the SNARE complexes, can modulate the release of neurotransmitters. Glia glutamate transporter (GLT) is one of the two glutamate transporters which account for most synaptic glutamate uptake in the CNS. The role of SNAP-25 and GLT as well as GAT is not clearly understood.

METHODS

We used the rat chronic constriction injury (CCI) model for research, and degraded SNAP-25 by a single intrathecal administration of BoNT/A. The mechanical (MWT) and thermal withdrawal latency (TWL) were tested. The level of SNAP-25, GLT, and GAT-1 were assayed using RT-PCR and Western blotting.

RESULTS

SNAP-25 was suppressed by a single intrathecal administration of 0.01U BoNT/A and the reduction of SNAP- 25 was correlated with the relief of nociceptive responses in CCI rats. MWT and TWL returned to normal from the 5th to 14th day (P < 0.05) after the administration. On the 14th day after surgery, compared to the sham group, the upregulation of SNAP-25 in CCI rats was reversed after BoNT/A treatment (P < 0.05). The decreased GLT was reversed after BoNT/A treatment but increased GAT-1 was not influenced by BoNT/A treatment.

CONCLUSIONS

SNAP-25 and GLT play important roles in the development of neuropathic pain, and the mechanism may involve the imbalance of neurotransmission after peripheral nerve injury. Intrathecal administration of BoNT/A reversed the upregulation of SNAP-25 and downregulation of GLT after CCI, but had no significant effect on the expression of GAT-1.

p300 exerts an epigenetic role in chronic neuropathic pain through its acetyltransferase activity in rats following chronic constriction injury (CCI)

BACKGROUND

Neuropathic pain is detrimental to human health; however, its pathogenesis still remains largely unknown. Overexpression of pain-associated genes and increased nociceptive somato-sensitivity are well observed in neuropathic pain. The importance of epigenetic mechanisms in regulating the expression of pro- or anti-nociceptive genes has been revealed by studies recently, and we hypothesize that the transcriptional coactivator and the histone acetyltransferase E1A binding protein p300 (p300), as a part of the epigenetic mechanisms of gene regulation, may be involved in the pathogenesis of neuropathic pain induced by chronic constriction injury (CCI). To test this hypothesis, two different approaches were used in this study: (I) down-regulating p300 with specific small hairpin RNA (shRNA) and (II) chemical inhibition of p300 acetyltransferase activity by a small molecule inhibitor, C646.

RESULTS

Using the CCI rat model, we found that the p300 expression was increased in the lumbar spinal cord on day 14 after CCI. The treatment with intrathecal p300 shRNA reversed CCI-induced mechanical allodynia and thermal hyperalgesia, and suppressed the expression of cyclooxygenase-2 (COX-2), a neuropathic pain-associated factor. Furthermore, C646, an inhibitor of p300 acetyltransferase, also attenuated mechanical allodynia and thermal hyperalgesia, accompanied by a suppressed COX-2 expression, in the spinal cord.

CONCLUSIONS

The results suggest that, through its acetyltransferase activity in the spinal cord after CCI, p300 epigenetically plays an important role in neuropathic pain. Inhibiting p300, using interfering RNA or C646, may be a promising approach to the development of new neuropathic pain therapies.

Etanercept decreases HMGB1 expression in dorsal root ganglion neuron cells in a rat chronic constriction injury model

In the present study, we examined the effect of etanercept on high mobility group box 1 (HMGB1) expression in dorsal root ganglion (DRG) neuron cells in a rat model of chronic constriction injury (CCI) of the sciatic nerve, with the aim of exploring the molecular mechanism underlying the therapeutic effect of etanercept on sciatica-related nociception and the potential interaction between tumor necrosis factor-α (TNF-α) and HMGB1 in DRG neuron cells. A rat CCI model was employed and the animals were randomly assigned to seven groups (n=20/group): untreated, sham only, sham/saline, sham/etanercept, CCI only, CCI/saline and CCI/etanercept. Our results revealed that compared with the sham/saline and sham/etanercept groups, thermal hyperalgesia and mechanical hyperalgesia, as well as HMGB1 expression at both the mRNA and protein levels in the DRG neuron cells, were induced by CCI, and were significantly inhibited by etanercept. Although etanercept showed no significant effect on the sham group, it significantly reduced the phosphorylated p38 mitogen-activated protein kinase (MAPK) levels induced by CCI in the DRG neuron cells. In conclusion, we demonstrated that etanercept significantly decreased the HMGB1 expression induced by CCI in the DRG neuron cells. This study not only explored the molecular mechanisms underlying the therapeutic effect of etanercept on sciatica-related nociception, but also provided indirect evidence for an interaction between TNF-α and HMGB1 in DRG neuron cells.

Temporal distribution of p300/CBP immunoreactivity in the adult rat spinal dorsal horn following chronic constriction injury (CCI)

p300 and its homolog cyclic AMP response element binding protein (CBP) are coactivators that were identified to participate in many biological processes including neural development and cognition. Their roles within the rodent spinal cord have not been reported systematically; in this study, their spatiotemporal distribution in the spinal cord of adult rat following chronic constriction injury (CCI) was studied. p300 and CBP expressed predominantly in nuclei in the gray matter of rat spinal cord. Rats undergoing CCI surgery showed increased p300/CBP immunoreactivity (IR) compared with normal control and sham-operated rats. The number of IR cells reached the peak at day 14 following CCI compared with those on day 3, 7, and 21, accompanied with significant behavioral changes of neuropathic pain. Cell-type determination by immunofluorescence at day 14 following CCI revealed that p300 and CBP expressed in neurons, but not in astrocytes or microglial cells. These results suggest that p300 and CBP are probably involved in the maintenance of neuropathic pain on spinal cord level. Furthermore, p300 and CBP may serve as a sensor only in neurons but not in astrocytes or microglia cells in the adult rat spinal cord.

Effects of intrathecal epigallocatechin gallate, an inhibitor of Toll-like receptor 4, on chronic neuropathic pain in rats

Numerous studies revealed that spinal inflammation and immune response play an important role in neuropathic pain. In this study, we investigated the effects of intrathecal injection of a Toll-like receptor (TLR4) inhibitor epigallocatechin gallate (EGCG) on neuropathic pain induced by chronic constriction injury of the sciatic nerve (CCI). A total of 120 rats were randomly assigned into 4 groups: sham-operated group, CCI group, CCI plus normal saline group and CCI plus EGCG group. CCI and sham surgeries were performed and both thermal hyperalgesia and mechanical allodynia were tested. Lumbar spinal cord was sampled and the mRNA and protein expressions of TLR4 and High Mobility Group 1 protein (HMGB1) were detected, the contents of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-10 (IL-10) were measured by ELISA, and immunohistochemistry for nuclear factor kappa B (NF-κB) was also carried out. When compared with the sham group, both mechanical and heat pain thresholds were significantly decreased, and the mRNA and protein expressions of TLR4 and HMGB1, the contents of TNF-α, IL-1β and IL-10 in the spinal cords and NF-κB expression in the spinal dorsal horn were markedly increased in CCI rats (P<0.05). After intrathecal injection of EGCG (1mg/kg) once daily from 1day before to 3days after CCI surgery, the expressions of TLR4, NF-κB, HMGB1, TNF-α and IL-1β were markedly decreased while the content of IL-10 in the spinal cord increased significantly accompanied by dramatical improvement of pain behaviors in CCI rats (P<0.05). These results show that the TLR4 signaling pathway plays an important role in the occurrence and development of neuropathic pain, and the therapy targeting TLR4 might be a novel strategy in the treatment of neuropathic pain.

Effect of human cytomegalovirus infection on the expression of Hoxb2 and Hoxb4 genes in the developmental process of cord blood erythroid progenitors

The aim of the present study was to investigate the role of Hoxb2 and Hoxb4 gene expression induced by human cytomegalovirus (HCMV) and/or all-trans retinoic acid (ATRA) on the proliferation and committed differentiation process of human cord blood hematopoietic stem cells (HSCs) to colony-forming erythroid progenitor cells (CFU-Es) in vitro. Cord blood was collected from the fetal placenta umbilical vein in 12 cases and cultured using hematopoietic stem cell culture technique in vitro. The proliferation and differentiation of cord blood HSCs to CFU-Es were continuously disrupted with HCMV-AD169 and/or 6 x 10⁻⁸ mol/l of ATRA. Expression levels of the Hoxb2 and Hoxb4 genes in the blank, ATRA, HCMV-AD169 and ATRA + HCMV treatment groups of CFU-Es were detected on day 3, 7 and 10 of culture by fluorescent quantitative reverse transcriptase-polymerase chain reaction method. Hoxb2 and Hoxb4 gene expression in each group began on day 3, obviously increased on day 7 and reached a peak on day 10. The expression levels of the Hoxb2 and Hoxb4 genes in the HCMV group were obviously down-regulated compared with the level in the blank group. However, expression levels of the Hoxb2 and Hoxb4 genes were significantly up-regulated in the HCMV + ATRA group compared with the HCMV group (P<0.05). Abnormal expression of the Hoxb2 and Hoxb4 genes induced by HCMV may play important roles in abnormal hematopoietic damage. They were also correlated with the process of erythroid hematopoiesis. ATRA (6 x 10⁻⁸ mol/l) significantly up-regulated expression of the Hoxb2 and Hoxb4 genes in the normal erythroid progenitor cells and in those cells infected with HCMV as well.

A new animal model of trigeminal neuralgia produced by administration of cobra venom to the infraorbital nerve in the rat

BACKGROUND

Understanding the mechanism of trigeminal neuralgia may be elucidated by developing laboratory animal models that closely mimic the features of this specific type of neuropathic pain. We have developed an experimental animal model for trigeminal neuralgia using a technique of injecting cobra venom into the infraorbital nerve (ION) trunk.

METHODS

Male Sprague-Dawley rats were subjected to the administration of cobra venom or saline into the ION trunk. Mechanical stimuli were applied to the ION territory in consecutive days after surgery. Mechanical thresholds were measured over a 90-day period on the bilateral facial region. Vascular permeability in the ION territory was measured using Evans blue dye.

RESULTS

The cobra venom-treated rats developed mechanical allodynia 3 days after surgery that lasted for 60 days postoperatively at the ipsilateral side. The mechanical thresholds of the contralateral ION territory also showed a profound decrease but were sustained for only approximately 30 days. There was no change of mechanical thresholds in the control groups. The extravasation of Evans blue increased significantly in the skin after administration of cobra venom to the ION compared with control rats (P < 0.05).

CONCLUSION

The cobra venom model may provide a reasonable model for investigating the mechanism of trigeminal neuropathic pain.

Intraoperative cardiac arrest during anesthesia: a retrospective study of 218,274 anesthetics undergoing non-cardiac surgery

BACKGROUND

Patient safety has been gained much more attention in recent years. The authors reviewed patients who had cardiac arrest in the operating rooms undergoing noncardiac surgery between January 1989 and December 2001 at the University of Pittsburgh Medical Center, USA. The main objectives of the study were to determine the incidence of intraoperative cardiac arrest, to identify possible causes of cardiac arrest and to explore amenable modifications.

METHODS

With approval by the University of Pittsburgh Institutional Review Board, patients experienced cardiac arrest during surgery were retrieved from medical records, surgical operation and anesthesia records and pathological reports by searching the Medical Archival Retrieval System (MARS), a hospital electronic searching system. Cases of cardiac arrest were collected over a period of thirteen years from the Presbyterian University Hospital (PUH), USA.

RESULTS

We found 23 cases of intraoperative cardiac arrests occurred in 218 274 anesthesia cases (1.1 per 10 000). Fourteen patients (60.8%) died in the operating room, leading to a mortality rate from all causes of 0.64 per 10 000 anesthetics. Immediate overall survival rate after arrest was 39% (9/23). Half of the patients (12/23) were emergency cases with 41% survival rate (5/12). One fourth of the arrests were trauma patients (6/23). Most arrest patients (87%, 20/23) were American Society of Anesthesiologists Physical Status (ASA PS) IV and V, while only three patients were ASA PS-I, II and III, respectively. One case was attributable to an anesthesia-related cardiac arrest and recovered after successful resuscitation.

CONCLUSIONS

Most intraoperative cardiac arrests were not due to anesthesia-related causes. Anesthesia-related cardiac arrests might have a higher survival rate when compared to other possible causes of cardiac arrest in the operating room.

Molecular cloning of rhamnose-binding lectin gene and its promoter region from snakehead Channa argus

Lectins are sugar-binding proteins that mediate pathogen recognition and cell-cell interactions. A rhamnose-binding lectin (RBL) gene and its promoter region have been cloned and characterized from snakehead Channa argus. From the transcription initiation site, snakehead rhamnose-binding lectin (SHL) gene extends 2,382 bp to the end of the 3' untranslated region (UTR), and contains nine exons and eight introns. The open reading frame (ORF) of the SHL transcript has 675 bp which encodes 224 amino acids. The molecular structure of SHL is composed of two tandem repeat carbohydrate recognition domains (CRD) with 35% internal identity. Analysis of the gene organization of SHL indicates that the ancestral gene of RBL may diverge and evolve by exon shuffling and gene duplication, producing new forms to play their own roles in various organisms. The characteristics of SHL gene 5' flanking region are the presence of consensus nuclear factor of interleukin 6 (NF-IL6) and IFN-gamma activation (GAS) sites. The results provide indirect evidence that up-regulation of SHL expression may be induced in response to inflammatory stimuli, such as lipopolysaccharide (LPS), interleukin 6 (IL-6), and interferon gamma (IFN-gamma). The transcript of SHL mRNA was expressed in the head kidney, posterior kidney, spleen, liver, intestine, heart, muscle, and ovary. No tissue-specific expressive pattern is different from reported STLs, WCLs, and PFLs, suggesting that different types of RBLs exist in species-specific fish that have evolved and adapted to their surroundings.

[Correlation between the Narcotrend index, the cerebral state index and the predicted effect site concentration during different state of consciousness in elderly patients with target controlled infusion of propofol]

OBJECTIVE

To study the correlation between the Narcotrend index, cerebral state index and predicted effect site concentration during different state of consciousness in the absence of surgery in elderly patients with target controlled infusion of propofol.

METHODS

Twenty patients aged from 65-75 years categorized as ASA class I - II who were scheduled to undergo general surgery under general anesthesia with target controlled infusion of propofol were recruited. During the target controlled infusion of propofol, the propofol infusion was set at an initial effect site concentration of 0.5 mg/L and increased by 0.5 mg /L every 5 min until the modified observer's assessment of alertness / sedation scale (OAA/S) values of zero. The predicted effect site concentration of propofol, the values of CSI and NCT were recorded and the sedation level was examined by the modified OAA/S every 20 s. The predicted effect site concentrations of propofol in target controlled infusion (TCI) system were recorded when they increased by more than 0.1 mg/L. The predicted effect site concentrations of propofol and the values of NCT and CSI at LVC and LOC of the patients were recorded.

RESULTS

There was a good linear correlation between NCT and the predicted effect site concentration of propofol (R2 = 0. 867, P < 0.01), as well as that between CSI and the predicted effect site concentration of propofol (R2 = 0.893, P < 0.01). The predicted effect site concentrations of propofol at LVC was (1.56 +/- 0.13) mg/L while the values of NCT was 74.00 +/- 4.69 and CSI 69.82 +/- 5.47. The predicted effect site concentrations of propofol at LOC was (2.15 +/- 0.27) mg/L while the values of NCT and CSI were 63.30 +/- 7.50 and 58.78 +/- 6.90 respectively. All of the values of NCT, CSI and the predicted effect site concentrations had a good linear correlation with OAA/S. There was a negative correlation between OAA/S and the predicted effect site concentration. At the same time, there was a positive correlation between OAA/S and NCT as well as that between OAA/S and CSI. And the correlation coefficients were - 0.968, 0.938, 0.940 respectively (P < 0.01). The values of NCT were higher significantly than that of CSI in different degree of LOC (P < 0.01).

CONCLUSION

During elder people's target controlled infusion of propofol, LVC and LOC occur within a definite range of predicted effect site concentrations. There is a good linear correlation between NCT, CSI and the predicted effect site concentrations of propofol. For the elders, both NCT and CSI reflect the sedation level of propofol. Although there is a significant correlation between NCT and CSI, a deviation does exist in a certain range. Therefore a simple 1:1 transfer from NCT to CSI is inadequate.

Comparative responses in rare minnow exposed to 17beta-estradiol during different life stages

Present in the excrement of humans and animals, 17beta-estradiol (E(2)) has been detected in the aquatic environment in a range from several nanograms to several hundred nanograms per liter. In this study, the sensitivities of rare minnows during different life stages to E(2) at environmentally relevant (5, 25, and 100 ng l(-1)) and high (1000 ng l(-1)) concentrations were compared using vitellogenin (VTG) and gonad development as biomarkers under semistatic conditions. After 21 days of exposure, VTG concentrations in whole-body homogenates were analyzed; the results indicated that the lowest observed effective concentration for VTG induction was 25 ng l(-1) E(2) in the adult stage, but 100 ng l(-1) E(2) in the larval and juvenile stages. After exposure in the early life stage, the larval and juvenile fish were transferred to clean water until gonad maturation. No significant difference in VTG induction was found between the exposure and control groups in the adults. However, a markedly increased proportion of females and appearance of hermaphrodism were observed in the juvenile-stage group exposed to 25 ng l(-1) E(2). These results showed that VTG induction in the adult stage is more sensitive than in larval and juvenile stages following exposure to E(2). The juvenile stage may be the critical period of gonad development. Sex ratio could be a sensitive biomarker indicating exposure to xenoestrogens in early-life-stage subchronic exposure tests. The results of this study provide useful information for selecting sensitive biomarkers properly in aquatic toxicology testing.

[Effect of controlled hypotension with different drugs combined with acute hypervolemic hemodilution on bleeding volume and gastrointestinal perfusion in nasal endoscopic surgery]

OBJECTIVE

To investigate the effect of controlled hypotension using different drugs on gastrointestinal perfusion and bleeding volume in nasal endoscopic surgery.

METHODS

Thirty ASA class I or II patients scheduled for nasal endoscopic surgery were randomized into three groups, including a routine general anesthesia group (group A) and two controlled hypotension groups (groups B and C). After anesthesia induction, anesthesia was maintained with 1%-2% isoflurane and vecuronium. ECG, mean arterial blood pressure (MAP), heart rate (HR), SpO(2) and PETCO(2) were continuously monitored. TRIP tonometry catheter 14 F was inserted into the stomach and connected to Tonocap (Datex-Ohmeda, Finland ). In groups B and C, hypotension was induced with isoflurane (1%-2%) and sodium nitroprusside (0.3-3 microg.kg(-1).min(-1)), and with isoflurane (1%-2%) and glonoine (0.5-5 microg.kg(-1).min(-1)), respectively, and the MAP was reduced to 50-55 mmHg in 10-15 min. In groups B and C, blood samples were taken for blood gas analysis after anesthesia (T(0)), after acute hypervolemic hemodilution (T(1)), at 30 and 60 min after controlled hypotension (T(2) and T(3)), and 30 min after recovery from hypotension (T(4)). In group A, blood samples were taken at different time points in the perioperative period.

RESULTS

The patients in groups B and C had smaller bleeding volume than those in group A. HR was decreased after moderate acute hypervolemic hemodilution, and increased after controlled hypotension (T(2) and T(3)) in comparison with that at T(1) to a level similar to that at T(0). No significant changes were found in pHi at T(2) and T(3) in comparison with that at T(1) in the three groups.

CONCLUSION

When appropriate measures are taken, induced hypotension at 50-55 mmHg does not necessarily produce disturbance in gastrointestinal perfusion. Induced hypotension with glonoin can decrease the bleeding volume better than sodium nitroprusside in nasal endoscopic surgery.

[Effect of human cytomegalovirus infection on the expression of hoxc4 and hoxc6 genes in the proliferation of lymphocytic progenitor cells]

The objective of this study was to observe the expression of hoxc4 and hoxc6 genes in the process of differentiation of hematopoietic stem cell (HSC) to colony forming unit-T Lymphocyte (CFU-TL) in vitro. and to explore the possible mechanism of HCMV-induced maldevelopment of human cord blood CFU-TL on genetic level through effecting the differentiation progress by human cytomegalovirus (HCMV) with and/or all-trans retinoic acid (ATRA), Normal CFU-TL culture was used as blank control. After detection with MTT, mRNA expression levels in the human cord blood CFU-TL hoxc4 and hoxc6 genes following HCMV infection and ATRA treatment were detected by fluorogenic quantitative reserve transcription polymerize chain reaction (FQ-RT-PCR) method. HCMV of 10(6) plaque formation unit (PFU)/ml was diluted to 0.1 ml 10(5) PFU/ml and added into the infected group. The results showed that the expression of hoxc4 and hoxc6 genes in the differentiation process increased slightly on day 3, and were up to the most on day 7 (p < 0.05), while became lower on day 12 respectively in normal group, HCMV group and ATRA group. Compared with the expression of hoxc6, the expression of hoxc4 was obviously higher in each group (p < 0.05). Compared with the expression of hoxc4 and hoxc6 genes in normal group, the expressions of hoxc4 and hoxc6 in ATRA group were up-regulated remarkably (p < 0.05), while the expressions of hoxc4 and hoxc6 in group HCMV were down-regulated (p < 0.05). It is concluded that the regular expression of hoxc4 and hoxc6 genes mRNA appeared in each group. A positive co-relationship exits between hoxc4/hoxc6 genes and lymphocytic progenitor hematopoiesis. Compared with the expression of hoxc6 gene, the expression of hoxc4 gene is obviously higher in each group. HCMV can down-regulate the expression of hoxc4 and hoxc6 genes and lead to suppression effect on cell morphology, which confirms that the normal hematopoietic lineage determination and maturation rely on the stable and consistent expression of homeobox gene. At the same condition, ATRA (6 x 10(-8) mol/L at 60 nmol/ml) can up-regulate hoxc4 and hoxc6 genes expression. ATRA can up-regulate the expression of hoxc4 and hoxc6 genes.

[Alterations of myelin basic protein concentration in the plasma and ultrastructure in the spinal cord after continuous intrathecal ropivacaine injection in rats]

OBJECTIVE

To explore the alterations of serum of myelin basic protein (MBP) concentration in the plasma and ultrastructure in the spinal cord after continuous intrathecal injection of different ropivacaine concentrations in rats.

METHODS

Ninety-six male Sprague-Dawley rats weighing 220 to approximately 280 g were randomly divided into a control group (Group N), Group R(1), R(2) and R(3) (24 rats in each group). Each group was subdivided into 4 subgroups (6 rats in each subgroup). According to the method of Yaksh's, a polyurethane microspinal catheter was inserted into the lumbar subarachnoid space in which 8 cm segment was left. Rats in each group were continuously received 40 microL of intrathecal injection of normal saline(Group N), 0.5%, 0.75%, and 1.0% ropivacaine (Group R(1),R(2),R(3)), 3 times every 1.5 hours. Blood (0.5 mL) was drawn from the femoral artery to determine serum concentrations of MBP at the detecting time T(0)(before inserted pipe)and T(1)(before the first intrathecal injection); for the subgroups, the examining time was at T(2), T(3), T(4) and T(5)(6, 12, 24 and 48 h respectively after the last time intrathecal administration). After blood was drawn, the rats in each subgroups were decapitated and the spinal cord of L(1-2) intumescentia lumbalis were immediately removed for electronic microscopic examination.

RESULTS

MBP levels were comparatively steady in Group N, R(1) and R(2), while there was statistical difference between Group R(3) and Group N, R(1),R(2),and R(3) (P<0.05). MBP level of Group R(3) was significantly higher at T(2),T(3),T(4) and T(5) than that at T(0)(P<0.01). The ultrastructural changes of the spinal cord in Group R(3) were pycnosis of most neurons, dilation of most rough endoplasmic reticulum, and vague structure of mitochondria and endocytoplasmic reticulum. A few neurons were completely de-generated losing the normal structure, with vacuole degeneration of crista mitochondriales or even partial loss.

CONCLUSION

The spinal cord ultrastructure is selectively vulnerable after intrathecal 1.0% ropivacaine injection, which may be one of the important pathophysiological bases for local anesthetic neurotoxicity. MBP may serve as a sensitive and specific indicator of spinal cord damage after intra-thecal administration of ropivacaine.

[Investigation and analysis of the incidence of awareness during general anesthesia]

OBJECTIVE

To investigate the incidence of awareness during general anesthesia in patients undergoing surgery.

METHODS

A total of 1,800 patients who underwent the selected and acute surgery with general anesthesia were enrolled. Brain function monitors were not used. Patients were interviewed twice during 24 h and 96 h postoperatively to determine intraoperative awareness.

RESULTS

Of all the inpatients, 13 (0.72%) reported clear awareness and never forgot anything during the operation; 145 (8.1%) reported dreaming during anesthesia with doubtful intraoperative recollection. Among the 145 patients, 108(74.5%) were females and 114(78.6%) received propofol anesthesia.

CONCLUSION

Intraoperative recollections are rare complication of general anesthesia, and are associated with the increased ASA physical status. Age and sex do not influence the incidence of awareness. Dreaming during anesthesia is related to younger females and propofol maintenance.

[Periaqueductal gray administration of HSV-I amplicon vector-mediated HPPE gene therapy of nocicepion in rats with formalin-induced pain]

OBJECTIVE

To investigate the antinociceptive effect of periaqueductal gray (PAG) administration of herpes simplex virus type-1(HSV-I) amplicon vector-mediated human preproenkephalin gene (HPPE).

METHODS

Sprague-Dawley rats weighting 260 to approximately 320 g were randomly divided into pHSVIRES-HPPE-LacZ (SHPZ) group, pHSVIRES-LacZ (SHZ) group, and saline (NS) group which included 3 d,1 week,2 week,3 week,4 week,5 week, and 6 week groups (n=51). The rats were anesthetized with intraperitoneal chloral hydrate (300 to approximately 350) mg/kg. Rats were PAG delivered with recombinant HSV-I amplicon vector SHPZ, SHZ or NS. One week after PAG administration 9 rats in each group were sacrificed and lumber segment of the spinal cord was removed for determination of expression of LacZ by X-gal staining and HPPE mRNA expression by reverse transcription-polymerase chain reaction and L-enkephalin content by radioimmunoassay in PAG. Formalin 50 microL (5%) was injected into the left hindpaw, and pain intensity scoring (PIS) was used to assess the antinociceptive effect.

RESULTS

After in vivo transferring, neurocyte demonstrated strong positive signals with X-gal immunohistochemical staining. The expression of HPPE mRNA was detected in PAG after administration of SHPZ. PAG delivery of SHPZ showed antinociceptive effect on formalin-induced pain for 6 weeks compared with SHZ group.

CONCLUSION

This amplicon virus can transfer HPPE into rat PAG neural cells and make it express efficiently. PAG administration of SHPZ can produce significant analgesic effect on formalin-induced pain in rats for 5 weeks.

[Application of remifentanil in neurosurgical anesthesia: a multi-center study]

OBJECTIVE

To observe the hemodynamic changes, recovery profiles, and side effects of propofol and remifentanil anesthesia by target controlled infusion (TCI). At different neurosurgical stages in patients undergoing neurosurgical operations.

METHODS

230 patients were scheduled for elective craniotomy in five hospitals in Beijing, Changsha, and Guangzhou. During the general anesthesia the plasma target-concentration of propofol remained unchangeable and the dose of remifentanil changed at different stages before skin incision, during skull opening, during intracranial procedure, and at skull closing. The hemodynamics changes and anesthetic recovery profiles were recorded.

RESULTS

The plasma target-concentrations of remifentanil were set to 3.0, 3.5, 3.6 and 3.4 ng/ml respectively. The time of consciousness loss during induction was (2.0 +/- 0.9) min. The mean arterial pressure (MAP) and heart rate (HR) decreased after induction (both P < 0.05) and increased after intubation. The hemodynamic changes were stable at different surgical stages and the HR was significantly lower than the baseline value (P < 0.01). MAP and HR increased gradually when the spontaneous breathing was recovered. 80, 41, 9, and 12 patients received nicardipine, atropine, esmolol, and ephedrine respectively during the operation. The times of recovery of spontaneous breathing, eye opening, extubation, and orientation were (12 +/- 9) min, (13 +/- 7) min, (16 +/- 8) min, and (21 +/- 8) min respectively.

CONCLUSION

When combined with 3 microg/ml propofol, the plasma target-concentrations of remifentanil, 3.0, 3.5, 3.6, and 3.4 ng/ml before skin incision, during skull opening, during intracranial procedure, and at skull closing respectively, can provide rapid induction, faster emergence , and better hemodynamic stability.

Impact of invasive fungal infection on outcomes of severe sepsis: a multicenter matched cohort study in critically ill surgical patients

Introduction

Fungal infection is increasingly common in critical illness with severe sepsis, but the influence of invasive fungal infection (IFI) on severe sepsis is not well understood. The aim of this study was to investigate the impact that IFI has on the outcomes of critically ill surgical patients with severe sepsis in China by means of matched cohort analysis; we also evaluated the epidemiologic characteristics of IFI in this population.

Methods

Records for all admissions to 10 university hospital surgical intensive care units (ICUs) from December 2004 to November 2005 were reviewed. Patients who met criteria for severe sepsis were included. IFI was identified using established criteria based on microbiologic or histological evidence. A matched cohort study was conducted to analyze the relationship between IFI and outcomes of severe sepsis.

Results

A total of 318 patients with severe sepsis were enrolled during the study period, of whom 90 (28.3%) were identified as having IFI. A total of 100 strains of fungi (58% Candida albicans) were isolated from these patients. Independent risk factors for IFI in patients with severe sepsis included mechanical ventilation (>3 days), Acute Physiology and Chronic Health Evaluation score, coexisting infection with both Gram-positive and Gram-negative bacteria, and urethral catheterization (>3 days). Compared with the control cohort, IFI was associated with increased hospital mortality (P < 0.001), high hospital costs (P = 0.038), and prolonged stay in the ICU (P < 0.001) and hospital (P = 0.020).

Conclusion

IFI is frequent in patients with severe sepsis in surgical ICUs and is associated with excess risk for hospital mortality, longer ICU and hospital stays, and greater consumption of medical resources.

[Intrathecal injection of ketamine and clonidine for chronic neuropathic pain model in rats]

OBJECTIVE

To observe the effect of intrathecal injection of ketamine and clonidine for chronic constriction injury (CCI) in rats.

METHODS

Thirty-two SD male rats weighing 220-280 g were anesthetized with intraperitoneal chloral hydrate 300 mg/kg. A catheter was implanted in the subarachnoid space at the lumbal region and CCI rat models were made successfully. On the 4th day after the surgery, the rats were randomly divided into 4 group: a control group,injecting 0.9%NS 20 microL intrathecally; a ketamine group, injecting ketamine 1 mg/kg(20 microL) intrathecally; a clonidine group (CL), injecting clonidine 20 microg/kg (20 microL) intrathecally; a combined ketamine and clonidine group, injecting ketamine 0.5mg/kg and clonidine 10 g/kg (20 microL) intrathecally, once a day for 1 week. BME-410A Plantar Analgesia Tester was used to measured pain threshold before the administration and 30 min after the administration. The rats were killed after the test was finished. And then we detected the nitric oxide synthase (NOS) activity and the NO production in the spinal cord.

RESULTS

The combined injection of ketamine (0.5mg/kg)and clonidine(10 g/kg) produced significantly more potent analgesia than the injection of ketamine (1 mg/ kg) or clonidine (20 microg/ kg)alone. The NOS activity and the production of NO in the combined injection group were significantly lower than those of the single injection group (P<0.05). The weight of rats post-administration increased obviously in the 4 groups (P<0.05).

CONCLUSION

The combined injection of ketamine and clonidine can produce synergistic ab-irritation without obvious side effects.

[Effects of BIS and AEPindex monitoring on the depth of anesthesia in in intravenous-inhalational anesthesia anesthesia]

OBJECTIVE

To evaluate the effects of bispectral index(BIS) and auditory evoked potentials index(AEPindex) monitoring on the depth of anesthesia in inhalation of isoflurane and target-controlled infusion(TCI) of propofol, and to observe the changes of BIS and AEPindex.

METHODS

Fourty ASA physical status I - II patients undergoing selective abdominal operations were divided into 2 groups randomly: Group I1(the end-tidal isoflurane concentration was 0.6 MAC, n=20) and Group I2(the end-tidal isoflurane concentration was 1.0 MAC, n=20). Anesthesia was induced with proprofol and vecuroninm. After the tracheal intubation, the patients were ventilated with 0.6/1.0 MAC isoflurane in pure oxygen, and after 20 minutes, propofol was administered with TCI according to the different target plasma concentrations from 1.0 g/mL to 3.0 g/mL(increasing 0.5 g/mL each time). The changes of MAP, HR, BIS and AEPindex were recorded simultaneously.

RESULTS

There was no close correlation between MAP, HR and the end-tidal isoflurane concentration, target plasma concentration of propofol. The correlation coefficiencies between BIS, AEPindex and the end-tidal isoflurane concentration were -0.757, -0.819 and -0.832, -0.878 (P<0.001), respectively; those between BIS, AEPindex and the target plasma concentration of propofol were -0.932, -0.888 and -0.920, -0.923 (P<0.001). The correlation coefficiencies between BIS, AEPindex and the stimulation of endotracheal intubation were -0.728 and 0.544, respectively; however, there was no close correlation between BIS , AEPindex and the stimulation of skin incision, and exploration.

CONCLUSION

BIS and AEPindex are reliable parameters to monitor the depth of anesthesia of isoflurane and propofol combined anesthesia; and in response to the stimulation of tracheal intubation, AEPindex is better than BIS, but BIS and AEPindex can not be used to predict the cardiovascular reaction of skin incision and exploration.

Effect of human cytomegalovirus on proliferation of hematopoietic progenitor cells of cord blood

OBJECTIVE

This study was designed to investigate the effect of human cytomegalovirus (HCMV) on the proliferation of colony forming unit granulocyte-macrophage (CFU-GM), CFU-erythroid (CFU-E), burst forming unit-erythroid (BFU-E), CFU-multipotential (CFU-Mix) and CFU-megakaryocytic (CFU-Mk) progenitor cells of cord blood in vitro as well as the possible mechanism.

METHODS

Twenty cord blood specimens were collected from the umbilical vein of normal full-term neonates delivered spontaneously. This study consisted of five groups: 3 Infection groups in which 0.1 mL 10(3), 10(4) and 10(5) plague forming unit (PFU) HCMV-AD169 virus solution was added to the culture system, an Inactivated control group in which the equal volume of inactivated virus solution was added, and a Blank control group (normal progenitor cells culture system without HCMV virus infection). Colony forming unit-assay was applied to detect the effects of HCMV-AD169 strain on the colony formation, inhibition rate and colony-maintaining duration of CFU- GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk of cord blood. PCR technique was used to demonstrate the existence of HCMV-DNA in the colony cells of cultured CFU-GM, CFU-E, CFU-Mix and CFU-Mk.

RESULTS

HCMV-AD169 (10(3)PFU) in low concentration had inhibition effects on colony formation of the CFU-Mix and CFU-Mk (P < 0.05), whereas 10(5) PFU and 10(4) PFU HCMV-AD169 lead to decreased colonies in CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk compared with the Blank control and the Inactivated control groups (P < 0.05). The suppression effect of HCMV on the colony formation was dose-dependent. The colony-maintaining duration of the CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk in the 10(5) PFU and 10(4) PFU HCMV infection groups was significantly shorter than that in the two control groups (P < 0.01). The low concentration of HCMV-AD169 (10(3)PFU) infection resulted in a shortened colony-maintaining duration of the CFU-Mix and CFU-Mk (P < 0.01), but had no effects on the colony-maintaining duration of CFU-GM, CFU-E and BFU-E. PCR amplification demonstrated the existence of HCMV-AD169 DNA in the colony cells of the three Infection groups.

CONCLUSIONS

HCMV-AD169 strain can infect hematopoietic progenitors of cord blood and inhibit the proliferation of hematopoietic progenitors, associated with anemia, neutropenia and thrombocytopenia in HCMV patients.

Comparative evaluation of the cerebral state index and the bispectral index during target-controlled infusion of propofol

BACKGROUND

Cerebral state index (CSI) has recently been introduced as an intra-operative monitor of anaesthetic depth. We compared the performance of the CSI to the bispectral index (BIS) in measuring depth of anaesthesia during target-controlled infusion (TCI) of propofol.

METHODS

Twenty Chinese patients undergoing general anaesthesia were recruited. CSI and BIS, and predicted effect-site concentration of propofol were recorded. The level of sedation was tested by Modified Observer's Assessment of Alertness/Sedation Scale (MOAAS) every 20 s during stepwise increase (TCI, 0.5 microg ml(-1)) of propofol. The loss of verbal contact (LVC) and loss of response (LOR) were defined by MOAAS values of 2-3 and less than 2, respectively. Baseline variability and the prediction probability (P(K)) were calculated for the BIS and CSI. The values of BIS(05) and CSI(05), BIS(50) and CSI(50), BIS(95) and CSI(95) were calculated at each end-point (LVC and LOR).

RESULTS

Baseline variability of CSI was more than that of BIS. Both CSI and BIS showed a high prediction probability for the steps awake vs LVC, awake vs LOR, and LVC vs LOR, and good correlations with MOAAS values.

CONCLUSION

Despite larger baseline variation, CSI performed as well as BIS in terms of P(K) values and correlations with step changes in sedation.

[Isobaric and hyperbaric local anesthetic used in spinal anesthesia]

OBJECTIVE

To reveal the advantages and disadvantages of the application of isobaric and hyperbaric local anesthetic in spinal anesthesia so as to provide reference for clinical practice.

METHODS

One hundred and sixty ASA patients (physical status I - II) undergoing lower abdominal surgery within 3 hours under spinal anesthesia (using CSEA technique via spinal needle in epidural needle) were allocated to 2 groups with 80 cases each. In lateral decubitus, patients randomly received a subarachnoid injection of 3.0 mL (15 mg) isobaric (Group I) or hyperbaric (Group H) bupivacaine and then turned supine. Hemodynamic changes and patients' responses were perioperatively observed. After subarachnoid injection, we recorded the time of onset and motor block, the peak sensory blocked level, the time of regression of 2 dermatomes, the time of the first administration of analgesics for a significant pain of the incision, the time of the regression of motor block to modified Bromage scale 2, and the time of recuperating the function of urination.

RESULTS

Both isobaric and hyperbaric 0.5% bupivacaine solutions in a volume of 3.0 mL provided effective sensory and motor block for the operations. The time of onset and complete motor block were similar in the two groups. Compared with Group I, the time of peak sensory block in Group H was shorter, the peak sensory block level was higher (more maximal dermatomes of blocked sensory nerves), the time of regression of sensory and motor block were shorter, the time of recuperating the function of urination was longer, and the incidence of feeling sick, nausea, vomiting and hypotension was higher.

CONCLUSION

Isobaric solution is superior to hyperbaric solution in spinal anesthesia.

[Clinical anesthetic effects of epidural ropivacaine with tramadol]

OBJECTIVE

To observe the anesthesic effects of epidural ropivacaine with tramadol during lower limbs surgery.

METHODS

Thirty patients (ASA I - II) scheduled for the lower limbs surgery were randomly divided into 2 groups with 15 patients in each group: group ropivacaine (R) and group ropivacaine with tramadol (T). The puncture was performed at the interspace of L2-3. Each patient was given 2% lidocaine 3 ml with 0.75% ropivacaine 10 ml which included NS 1 ml in Group R or tramadol 50 mg in Group T. The potency of analgesia, the time of sensation block to T12 and T10, the time to the highest plane of analgesia, the lasting time of analgesia, the degree of sedation, the degree of motor block, and the side effects were recorded and analyzed during anesthesia after the first dose.

RESULTS

The time of sensation block which reached T12 and T10 and the time to the highest plane of analgesia decreased significantly in Group T than that in Group R (P < 0.05). The lasting time of analgesia in Group T was longer than that in Group R (P < 0.05). There was no significant difference in the potency of analgesia, the degree of sedation and motor block, and the side effects (P > 0.05).

CONCLUSION

The epidural ropivacaine with tramadol enhanced the anesthetic effects of ropivacaine.

[Effects of desflurane on auditory evoked potential index and quantitative electroencephalogram]

OBJECTIVE

To observe the effects of desflurane on A-line ARX Index (AAI), QEEG, MAP and HR, and to investigate the feasibility of AAI, QEEG, MAP and HR in monitoring the depth of anesthesia with desflurane.

METHODS

Thirty patients classified as ASA physical status I approximately II were scheduled for elective lower abdominal surgery. Anesthesia was induced with propofol and vecuronum. After the tracheal intubation, the lungs were ventilated with desflurane in oxygen. End-tidal desflurane concentrations were maintained at 0.8, 1.0 and 1.3 MAC for 20 minutes, respectively. The parameters of record included AAI, BIS (bispectral index), SEF (95% spectral edge freqency), MF (midian freqency), MAP and HR.

RESULTS

AAI, BIS, SEF and MF significantly decreased in a linear manner (r = 0.830, 0.930, 0.803, and 0.885, respectively, P < 0.01) with increasing end-tidal concentration of desflurane range of 0.8 approximately 1.3 MAC. MAP and HR did not change much. HR increased significantly at concentration 1.3 MAC than that of 1.0 MAC.

CONCLUSION

Within end-tidal desflurane concentration range 0.8 approximately 1.3 MAC, both AAI and parameters derived from EEG (such as BIS, SEF, MF) can serve as parameters in monitoring the depth of anesthsia with desflurane, while MAP and HR can not.

[Study of the reproducibility and sensitivity of laser microspectral analysis in argon atmosphere at reduced pressure]

In argon atmosphere at reduced pressure, the spectral analysis reproducibility and sensitivity are experimentally studied with the laser microprobe emission spectral analysis(LMESA) system for the metal alloy standard samples. For the atomic spectral analysis line, the relative standard deviation(RSD) in argon atmosphere at reduced pressure is better than that in air atmosphere. For the ionic spectral analysis line, the RSD is almost the same in both cases. The RSD is strongly affected by the composition of the sample and the concentration of elements. The measured slope of calibration curves for the determination of Cu, Zn and Mg in an aluminum alloy in argon atmosphere is about 1.5-2 times of that in the air atmosphere, which indicates an obvious improvement of the sensitivity and is helpful to expand the dynamic range of the spectral analysis.