Operative timing and the safety of emergency laparoscopic cholecystectomy: A retrospective analysis.

The ideal operative timing for laparoscopic cholecystectomy (LC) remains controversial, particularly in emergency patients. This study aimed to evaluate the necessity of operative timing for emergency LC. One hundred ninety-four patients who had undergone operative timings were classified into groups of <72h and >72h from the onset of symptoms to the operation. Baseline data, basic disease, operative bleeding, complications, and conversion rates were analyzed by Variance analysis and logistic regression analysis. The total morbidity of postoperative complication was 4.93% and 3.84% (P = .751) in the <72h and >72h groups respectively. The complication and conversion to LC were mainly influenced by age and gallbladder volume (odds ratio [OR] = 1.078, P = .013, and OR = 1.035, P = .031), but not by operative timing (P = .292). The intraoperative blood loss was closely correlated with the gallbladder volume (OR = 1.019, P = .025) by logit regression analysis, and correlation coefficient of R = 0.436, P < .01. Our results suggest that it is not necessary to confine the operative timing of LC to within 72h from the onset of symptoms, and gallbladder volume should be emphasized in the operative timing for emergency LC.

Clinicopathological difference between gastric cancer in the lesser curvature and gastric cancer in the greater curvature.

Gastric cancer (GC) is a heterogeneous disease; the tumor distribution and molecular subtype could affect the prognosis of patients with GC. However, the clinicopathological difference between GC in the lesser and that in the greater curvature remains unknown. In this study, we aimed to investigate the difference and provide new clues for the treatment of GC. Between January 2010 and August 2014, 1249 consecutive patients with GC in the lesser or greater curvature were treated in our surgery department; data related to the demographic characteristics, pathological type, tumor grade, tumor size, TNM stage, tumor markers, operative methods, complications, and follow-up were retrospectively analyzed using a univariate analysis and the Kaplan-Meier method. The tumor size in lesser curvature was larger than that in the greater curvature (4.95 ± 2.57 vs 4.43 ± 2.62 cm, P = .034); patients with GC in the lesser curvature had a higher incidence of total gastrectomy and a lower incidence of distal gastrectomy than those with GC in the greater curvature (60.2% vs 43.2%, and 34.8% vs 49.2%, P = .002). No significant differences were found in the 5-year survival rate between patients with GC in the greater curvature and those with GC in the lesser curvature (62.6% vs 66.1%, P = .496). The epidermal growth factor receptor (EGFR) expression rate of tumors in the lesser curvature was 40.55%, which was significantly higher than that of tumors in the greater curvature (25.92%, P = .024), while the 5-year survival rate of patients with EGFR-positive expression was 50.8%, which was significantly lower than that of patients with EGFR-negative expression (64.8%, P = .021). Significant differences were observed in the clinicopathological features between GC in the lesser curvature and that in the greater curvature. These differences contribute to the improvement in the treatment outcome.

The expression of epidermal growth factor receptor 1 and human epidermal growth factor receptor 2 based on tumor location affect survival in gastric cancer.

To investigate the different expression of epidermal growth factor receptor 1 (EGFR) and human epidermal growth factor receptor 2 (HER2) in gastric cancer based on tumor locations and its impact on patients survival.Gastric cancer is heterogeneous disease, recent years have established a molecular classification and described distribution of molecular subtypes in stomach. However, the difference of EGFR and HER-2 expression among tumor location is still unknown.Between January 2010 and August 2014, 2477 consecutive patients with gastric cancer were treated in our surgery department. The tumor locations were classified into 4 groups: cardia, fundus, corpus, and antrum. Based on tumor locations, the clinicopathologic characteristics, EGFR and HER-2 expression, and follow-up data were analyzed by univariant analysis and Kaplan-Meier analysis retrospectively.There were difference of gender, age, Borrmann type, pathological type, differentiation, T-stage, tumor size, gastrectomy method, and complications among the locations. The positive rate of EGFR expression in fundus was 18.18%, which was lower than cardia (46.21%), corpus (43.62%), and antrum (48.83%) (P < .001). The 5-year survival rate in EGFR positive patients was 50.8%, which was significantly lower than EGFR negative patients (64.0%, P = .021). The positive rate of HER-2 expression in cardia was 48.15%, which was significantly higher than fundus (37.5%), corpus (35.45%), and antrum (38.54%) (P = .009), but HER-2 expression did not correlate with 5-year survive (P = .548).Our results suggest that there exist difference of EGFR and HER-2 expression based on tumor locations, and the distribution of EGFR impact on patients survival. Emphasizing the role of EGFR and HER-2 in the context of location contribute to make appropriate treatment strategy and improve prognosis of gastric cancer.

Postoperative intraperitoneal hyperthermic perfusion improve survival for advanced gastric cancer.

To evaluate the value of intraperitoneal hyperthermic perfusion (IPHP) in the treatment of gastric cancer.Gastric cancer (GC) is a malignancy with poor prognosis, recent years have demonstrated advances in the use of IPHP for the treatment of advanced gastric cancer (AGC), but the outcome is controversial.Between January 2015 and January 2017, 134 patients with GC were treated with IPHP in our surgery department, 130 of them were advanced GC patients, and other 1439 cases were treated without IPHP for comparison. In this retrospective cohort study, demographic, perioperative data, and follow-up data were analyzed by univariant analysis, Kaplan-Meier and Cox regression survival analysis.We found the 1-year survival in IPHP group was significantly longer than it in non-IPHP group (85.5% vs 73.8%, P = .027). and IPHP decreased mortality 1.8 times in 2-year course (OR = 0.556, P = .004). The incidence rate of total complications in IPHP group was similar to that in the Non-IPHP group (6.67% vs 7.46%, respectively; P = .718). We classified all patients into four groups, operation alone, operation + chemotherapy, operation + IPHP, and operation + IPHP + chemotherapy. The 1-year survival in the groups was 70.2%, 77.5%, 83.1%, and 93.5%, respectively (P = .001), compared with the group of operation alone, the 2-year mortality risk was decreased 1.76 times (OR = 0.569, P = .030) and 2.59 times (OR = 0.385, P = .022) in operation + IPHP group and operation + IPHP + chemotherapy group.Our results suggest that IPHP could contribute to improve survival of patients with gastric cancer. And the modality of operation + IPHP + chemotherapy is the optimal treatment modality for gastric cancer.

Safety of total gastrectomy without nasogastric and nutritional intubation.

The aim of the present study was to evaluate the safety of gastrectomy without nasogastric and nutritional intubations. Between January 2010 and August 2015, 74 patients with gastric cancer received total gastric resection and esophagogastric anastomosis without nasogastric and nutritional intubations at the First Department of Digestive Surgery of the XiJing Hospital of Digestive Diseases (Xi'an, China), of whom 42 were also received earlier oral feeding within 48 h. The data were retrospectively analyzed. An additional 301 cases who underwent traditional postoperative intubation were used for comparison. In patients without intubation compared with those managed traditionally with intubation, the mean operative time was decreased (190.97±38.18 vs. 216.12±59.52 min, respectively; P=0.026). In addition, the postoperative activity was resumed earlier (1.16±0.47 vs. 1.36±0.84 days, respectively; P=0.009), oral food intake was started earlier (4.28±1.79 vs. 5.71±2.66 days, respectively; P=0.009), the incidence of fever was lower (12.16 vs. 29.23%, respectively; P=0.003), and the incidence of total complications was not statistically significantly different between the two groups (9.41 vs. 6.31%, respectively; P=0.317). There were no significant differences regarding complications of the anastomotic port (1.37 vs. 1.69%, respectively; P=0.849). Compared with traditional postoperative management, earlier oral feeding did not increase the incidence of complications (7.21 vs. 4.76%, respectively; P=0.557). Our results suggest that total gastric resection without nasogastric and nutritional intubation is a safe and feasible option for patients undergoing total gastrectomy.

Mesenchymal stem cells promote tumor angiogenesis via the action of transforming growth factor ß1.

Mesenchymal stem cells (MSCs) may influence the growth and metastasis of various human malignancies, including hepatocellular carcinoma (HCC). Therefore, the underlying mechanisms via which MSCs are able to affect malignancies require investigation. In the present study, the potential role of MSC in the angiogenesis of HCC was investigated. A total of 17 nude mouse models exhibiting human HCC were used to evaluate the effects of MSC on angiogenesis. A total of 8 mice were injected with human MSCs via the tail vein, and the remaining 9 mice were injected with phosphate-buffered saline as a control. A total of 35 days subsequent to the injection of MSCs, the microvessel density (MVD) of tumors was evaluated by immunostaining, using cluster of differentiation 31 antibody. The mRNA levels of transforming growth factor (TGF)ß1, Smad2 and Smad7 were detected using reverse transcription-quantitative polymerase chain reaction. Protein expression levels of TGFß1 and vascular endothelial growth factor (VEGF) in tumor tissues were analyzed using ELISA. Compared with controls, MVD in MSC-treated mice was significantly increased (28.00±9.19 vs. 18.11±3.30; P=0.006). The levels of TGFß1 mRNA in the MSC-treated group were 2.15-fold higher compared with the control group (1.27±0.61 vs. 0.59±0.39; P=0.033), and MVD was higher in the group exhibiting increased TGFß1 mRNA levels compared with the control group (26.50±9.11 vs. 19.44±6.14; P=0.038). In addition, a close correlation between the expression levels of TGFß1 and VEGF was identified. The results of the present study suggested that MSCs may be capable of enhancing the angiogenesis of HCC, which may be partly due to the involvement of TGFß1.

Efficacy of single-layer continuous suture of the posterior wall in anastomosis involving a difficult location of the digestive tract.

Surgery for digestive tract disease predominantly consists of reconstruction and anastomosis. Due to the difficult location, anastomosis is extremely challenging and the risk of complication increases accordingly. Traditional manual anastomosis and the application of a stapling device are insufficient. Therefore, the aim of this study was to investigate the feasibility and safety of a novel manual method in a difficult anastomotic location, consisting of a single-layer continuous suture in the posterior wall. In total, 15 beagle dogs were included in the study; eight underwent surgery with the novel manual method for reconstruction and anastomosis of the digestive tract, while seven underwent surgery with the stapler device as a control. The subsequent postoperative complications were observed and, three months later, the anastomotic ports were excised, and the pathological formation and morphological changes were evaluated. No statistically significant differences were identified between the total (50.0 vs. 57.1%; P=0.782) and anastomotic (0.0 vs. 28.6%; P=0.200) complication rates in the manual suture and staple suture groups, respectively. Compared with the control group, the operative expenditure was lower in the manual group (1726.7±33.5 vs. 2135.7±43.1 renminbi; P=0.001), the diameter of the anastomotic port was larger in the manual group (3.04±0.07 vs. 2.24±0.25 cm; P=0.004) and the thickness of the anastomotic port (in cm) was thinner in the manual group (2.94±0.06 vs. 5.07±0.85; P=0.002). Furthermore, the pathological formation of the anastomositic port in the manual group was improved. The results of the current study suggest single-layer continuous suture of the posterior wall in anastomosis of the digestive tract to be a novel method with feasibility and safety, particularly in difficult anastomotic locations.

Single-layer continuous suture contributes to the reduction of surgical complications in digestive tract anastomosis involving special anatomical locations.

The key point of digestive cancer surgery is reconstruction and anastomosis of the digestive tract. Traditional anastomoses involve double-layer interrupted suturing, manually or using a surgical stapler. In special anatomical locations, however, suturing may become increasingly difficult and the complication rate increases accordingly. In this study, we aimed to investigate the feasibility and safety of a new manual suturing method, the single-layer continuous suture in the posterior wall of the anastomosis. Between January, 2007 and August, 2012, 101 patients with digestive cancer underwent surgery in Xi'an Gaoxin Hospital. Of those patients, 27 underwent surgery with the new manual method and the remaining 74 underwent surgery using traditional methods of anastomosis of the digestive tract. Surgical time, intraoperative blood loss, drainage duration, complications, blood tests, postoperative quality of life (QOL) and overall expenditure were recorded and analyzed. No significant differences were observed in surgical time, intraoperative blood loss, temperature, blood tests and postoperative QOL between the two groups. However, compared with the control group, the new manual suture group exhibited a lower surgical complication rate (7.40 vs. 31.08%; P=0.018), lower blood transfusion volume (274.07±419.33 vs. 646.67±1,146.06 ml; P=0.053), shorter postoperative hospital stay (14.60±4.19 vs. 17.60±6.29 days; P=0.038) and lower overall expenditure (3,509.85±768.68 vs. 6,141.83±308.90 renminbi; P=0.001). Our results suggested that single-layer continuous suturing for the anastomosis of the digestive tract is feasible and safe and may contribute to the reduction of surgical complications and overall expenditure.

Clinical significance of P-glycoprotein and glutathione S-transferase π expression in gallbladder carcinoma.

P-glycoprotein (P-gp) and glutathione S-transferase π (GST-π) are not only drug-resistance markers, but also prognostic markers of various cancers. The aim of the present study was to investigate the clinical significance of P-gp and GST-π in gallbladder carcinoma (GBC). Tissue samples from 42 patients with GBC were immunostained. Demographic, clinical and follow-up data were collected and analyzed. The positive expression rates of P-gp and GST-π in the GBC tissues were significantly higher (76.2 and 64.3%, respectively) than that of chronic cholecystitis specimens (30 and 20%, respectively) (P=0.014 and 0.035, respectively), and correlated with the Nevin stage of GBC. Multivariate analysis demonstrated that patients with positive expression of P-gp and GST-π showed a significantly lower 2-year survival rate (11.1 and 12%, respectively) compared with patients with negative expression (55.6 and 45.5%, respectively) (P=0.013 and 0.036, respectively). P-gp was also found to be an independent prognostic marker of 2-year survival rate by logistic regression analysis (B=-2.76, P=0.061). Results of this study suggest that P-gp is a prognostic marker of GBC and the detection of P-gp and GST-π may contribute to the prognosis of GBC and the application of chemotherapy as a therapeutic treatment.

[Observation on the anesthesia effect of general anesthesia assisted by auricular-plaster therapy in gynecological surgery].

OBJECTIVE: To observe the impacts on anesthetic dosage and postoperative pain under general anesthesia assisted by auricular-plaster therapy. METHODS: One hundred and twenty cases of gynecological laparoscopic surgery were randomized into three groups, 40 cases in each one. In auricular point group A, the magnetic beads were stick on the auricular points which were Shenmen (TF4), Lung (fei, CO14), Spleen (pi,CO13), Stomach (wei, CO4), Large Intestine (dachang, CO7), Adrenal (shenshangxian, TG2 (P)), Endocrine (neifenmi, CO18), Uterus and Pelvic Cavity(penqiang, TF5) etc. In auricular point group B, the magnetic beads were stick on the preauricular points and the corresponding retroauricular points of the ears. In a placebo group, the plasters of the same appearance were stick on the corresponding auricular points of the ears. The anesthetic method was same in three groups and the anesthesia effect were assessed and compared among the three groups. RESULTS: In surgery, the dosage of sufentanil, the narcotic analgesic was (22.08 +/- 7.11) microg in auricular point group A and was (20.19 +/- 7.21) microg in auricular point group B, which were reduced as compared with (26.13 +/- 9.04) microg in the placebo group (both P < 0.05). The difference in the dosage of propofol, the anesthetic was not significant statistically among three groups (P > 0.05). On the 1st day after surgery, the score of pain visual analogue scale (VAS) was (1.77 +/- 1.65) in auricular point group A and was (1.80 +/- 1.96) in auricular point group B, which were reduced as compared with (2.62 +/- 1.46) in the placebo group (both P < 0.05). Before surgery, the serum beta-endorphin (beta-EP) was (198.8 +/- 124.1) pg/mL in auricular point group A and was (207.2 +/-102.7) pg/mL in auricular point group B, which were higher apparently as compared with (143.6 +/- 87.1) pg/mL in the placebo group (both P < 0.05). The differences in the above indices were not significant statistically between the two auricular point groups. CONCLUSION: The auricular-plaster therapy reduces the dosage of anesthetic, alleviates postoperative pain and acts on tranquilization and analgesia. The effect is not intensified apparently in the treatment for the magnetic beads sticking on both preauricular points and the corresponding retroauricular points of the ears.

Dopamine receptor 1 modulates the discharge activities of inspiratory and biphasic expiratory neurons via cAMP-dependent pathways.

Dopamine receptor 1 (D(1)R) plays an essential role in regulating respiratory activity in mammals, however, little is known about how this receptor acts to modulate the basic respiratory rhythmogenesis. Here, by simultaneously recording the discharge activities of biphasic expiratory (biphasic E) neurons/inspiratory (I) neurons and the XII nerve rootlets from brainstem slices, we found that the application of D(1)R agonist cis-(±)-1-(aminomethyl)-3,4-dihydro-3-phenyl-1H-2-benzopyran-5,6-diolhydrochloride (A68930, 5 µM), or forskolin, an intracellular cAMP-increasing agent, substantially decreased respiratory cycle and expiratory time of both types of neurons, and elevated the integral amplitude and frequency of XII nerve rootlets discharge. These changes were reversed by subsequent application of their antagonists SCH-23390 and Rp-Adenosine 3',5'-cyclic monophosphorothioate triethylammonium salt hydrate (Rp-cAMPS), respectively. Importantly, after pretreatment with Rp-cAMPS, the effects of A68930 in both types of neurons were blocked, suggestive of a cAMP-dependent action of A68930. Thus, the current study indicates that D(1)R may modulate basic breathing rhythmogenesis via cAMP-dependent mechanisms.

Mesenchymal stem cells seldomly fuse with hepatocellular carcinoma cells and are mainly distributed in the tumor stroma in mouse models.

Mesenchymal stem cells (MSCs) can have an effect on the growth and metastasis of human malignancies, including hepatocellular carcinoma (HCC); however, their mechanisms of action are not yet fully understood. The cell fusion of stem cell derived from bone marrow with other cells has been increasingly emphasized. The purpose of this study was to investigate the distribution of MSCs in mouse models of HCC, as well as the cell fusion between MSCs and HCC cells. We labeled HCC cells and MSCs with green fluorescence protein (GFP), red fluorescence protein (RFP), 4',6-diamidino-2-phenylindole (DAPI) and 5-bromo-2'-deoxyuridine (BrdU). We found that MSCs fused with HCC cells at a low frequency in vitro. MSCs were found to be merged into HCC tissues after intravenous injection, and compared with the mice not injected with MSCs, the MSCs were mainly distributed in the tumor stroma; Following the injection of the MSCs, the tumor stroma was found to have expanded in size, and the rate of pulmonary metastasis in the MSC-injected group was significantly lower (20%) compared to that in the group not injected with MSCs (100%, P=0.01). These data suggest that cell fusion between MSCs and HCC after engraftment is not one of the main mechanisms of action of the MSCs, while stromal differentiation is a major mechanism of action of the MSCs, leading to the inhibition of the pulmonary metastasis of HCC.

TGF beta1 and related-Smads contribute to pulmonary metastasis of hepatocellular carcinoma in mice model.

BACKGROUND: Recent studies indicate that Transforming Growth Factor beta (TGF ß) correlated with pulmonary metastasis of cancers. However, the correlation between TGF ß and pulmonary metastasis of hepatocellular carcinoma (HCC) is till unknown. METHODS: We detected the in vitro and in vivo expression levels of TGF ß1/Smads by Real-time PCR and Western blot in MHCC97-H and MHCC97-L cell lines, which are HCC cell lines and have higher and lower pulmonary metastatic potential respectively. RESULTS: TGF ß1 mRNA level in MHCC97-L tumors were higher than that in MHCC97-H tumors, (2.81±1.61 vs. 1.24±0.96, P=0.002), TGF ß1 protein level in MHCC97-L tumors were also higher than that in MHCC97-H tumors (1.37±0.95 vs. 0.32±0.22, P<0.001). In addition, the TGF ß1 mRNA level positively correlated with pulmonary metastasis, and the relations between TGF ß1 and Smads were also found (R2=0.12 and 0.40, respectively). CONCLUSIONS: Our results suggest that TGF ß/ Smads promote pulmonary metastasis of HCC.

[Involvement of cAMP-PKA pathway in group â ¡ metabotropic glutamate receptors-mediated regulation of respiratory rhythm from neonatal rat brainstem slice].

The study aims to identify the role of cAMP-PKA pathway in the group Ⅱ metabotropic glutamate receptors (mGluRs)-mediated regulation of respiratory rhythm from the brainstem slice. Neonatal (aged 0-3 d) Sprague-Dawley rats of either sex were used. The brainstem slice containing the medial region of the nucleus retrofacialis (mNRF) and the hypoglossal nerve rootlets was prepared, and the surgical procedure was performed in the modified Kreb's solution (MKS) with continuous carbogen (95% O2 and 5% CO2) bubbling, and ended in 3 min. Respiratory rhythmical discharge activity (RRDA) of the hypoglossal nerve rootlets was recorded by suction electrode. Eighteen brainstem slice preparations were divided into 3 groups. In group 1, group Ⅱ mGluRs specific antagonist (2S)-α-ethylglutamic acid (EGLU) was added into the perfusion solution for 10 min. In group 2, after application of Forskolin for 10 min, washout with MKS, the slice was perfused with Rp-cyclic 3', 5'-hydrogen phosphorothioate adenosine triethylammonium salt (Rp-cAMPS) alone for another 10 min. In group 3, after application of Rp-cAMPS for 10 min, additional EGLU was added into the perfusion for another 10 min. The results showed EGLU shortened respiratory cycle (RC), but the changes of integral amplitude (IA) and inspiratory time (TI) were not statistically significant. Forskolin induced significant decreases in RC, and increased TI, IA. Rp-cAMPS could make the opposite effect compared with the changes of RRDA with Forskolin. The effect of EGLU on the RRDA was inhibited after blocking the cAMP-PKA pathway. Taken together, cAMP-PKA pathway may play an important role in the group Ⅱ mGluRs-mediated regulation of RRDA in the brainstem slice of neonatal rats.

Association of specific genotypes in metastatic suppressor HTPAP with tumor metastasis and clinical prognosis in hepatocellular carcinoma.

The phosphatidic acid phosphatase HTPAP has been defined as a metastatic suppressor of hepatocellular carcinoma (HCC), but little is known about its function or potential applications as a prognostic marker. In this study, we analyzed patterns of HTPAP genetic variation and gene expression in 864 patients who underwent HCC resection, assessing these patterns for correlations to tumor metastasis potential. Focusing on two tagSNPs that were selected (+357G/C and +1838A/G), we found that only the +357G/C genotype was significantly associated with HTPAP mRNA and protein expression levels and the probability of metastasis. In an independent cohort of 665 HCC patients, we determined that the +357G/C genotype was associated with shorter time to recurrence and overall survival. Together, these results indicated that the HTPAP tagSNP +357 GG+GC genotypes may influence HCC metastatic potential and clinical prognosis by down-regulating HTPAP expression. Extending these results, a global expression profiling analysis identified 41 genes including the pro-inflammatory genes IL-8 and TLR2 that were significantly overexpressed in the +357 GG+GC group, as possible coregulated markers with HTPAP. Together, our findings identify an HTPAP genotype and associated gene expression pattern that favors metastasis progression and that could be used to predict tumor metastasis and prognosis in HCC patients.

Human mesenchymal stem cells inhibit metastasis of a hepatocellular carcinoma model using the MHCC97-H cell line.

The effects of mesenchymal stem cells (MSC) on the growth and metastasis of human malignancies including hepatocellular carcinoma (HCC) are controversial, and the underlying mechanisms are not yet understood. The aim of this study was to explore the role of MSC in the progression of HCC. We investigated the effect of MSC on in vitro proliferation and invasion and in vivo tumor growth and pulmonary metastasis of MHCC97-H HCC cells with a high metastatic potential. The mRNA and protein levels of transforming growth factor-beta 1 (TGFß1) and MMP, and their association with the effects of MSC on HCC cells were also evaluated. Co-culture of MHCC97-H cells with MSC conditioned medium significantly enhanced in vitro proliferation but inhibited invasiveness. Following MSC treatment of a nude mouse model bearing human HCC, the MSC were predominantly located in the HCC tissues. Compared with controls, MSC-treated mice exhibited significantly larger tumors (3080.51 ± 1234.78 mm(3) vs 2223.75 ± 1000.60 mm(3), P = 0.045), but decreased cellular numbers of lung metastases (49.75 ± 18.86 vs 227.22 ± 74.67, P = 0.046). Expression of TGFß1 and MMP-2 was significantly downregulated in the MSC-treated HCC cells. TGFß siRNA concurrently downregulated expression of TGFß and MMP-2 in HCC cells and blocked the MSC-induced proliferation and invasiveness of MHCC97-H cells. The MSC enhanced tumor growth but significantly inhibited the invasiveness and metastasis of HCC, possibly through downregulation of TGFß1. These findings suggest that MSC could be useful in controlling metastatic recurrence of HCC.

[Group II metabotropic glutamate receptors is involved in the modulation of respiratory rhythmical discharge activity in neonatal rat medullary brain slices].

OBJECTIVE: To explore the role of group II metabotropic glutamate receptors in the modulation of basic respiratory rhythm. METHODS: Neonatal (0-3 days) SD rats of either sex were used. The medulla oblongata brain slice containing the medial region of the nucleus retrofacialis (mNRF) and the hypoglossal nerve rootlets was prepared, and the surgical procedure was performed in the modified Kreb's solution (MKS) with continuous carbogen (95% O2 and 5% CO2) within 3 min. The brain slices were quickly transferred to a recording chamber and continuously perfused with oxygen-saturated MKS at a rate of 4-6 ml/min at 27-29 degrees celsius. Eighteen medulla oblongata slices were divided into 3 groups and treated for 10 min with group II metabotropic glutamate receptor-specific agonist 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (APDC) (at concentrations of 10, 20, 50 micromol/L), group II metabotropic glutamate receptor antagonist (2S)-alpha-ethylglutamic acid (EGLU) (300 micromol/L), or APDC (50 micromol/L)+EGLU (300 micromol/L) after a 10 min APDC (50 micromol/L) application. Respiratory rhythmical discharge activity (RRDA) of the rootlets of the hypoglossal nerve was recorded by suction electrodes. RESULTS: APDC produced a dose-dependent inhibitory effect on the RRDA, prolonging the respiratory cycle and expiratory time and decreasing the integral amplitude and inspiratory time. EGLU induced a significant decrease in the respiratory cycle and expiratory time. The effect of APDC on the respiratory rhythm was partially reversed by the application of APDC+EGLU. CONCLUSION: Group II metabotropic glutamate receptors are probably involved in the modulation of the RRDA in isolated neonatal rat brainstem slice.

[Effect of sevoflurane versus propofol-remifentanil anesthesia on neuromuscular blockade by continuous cisatracurium infusion].

OBJECTIVE: To compare the effects of sevoflurane and propofol-remifentanil anesthesia on neuromuscular blockade produced by continuous cisatracurium infusion. METHODS: Forty ASA I or II patients undergoing selective surgery were randomly divided into sevoflurane and propofol-remifentanil anesthesia groups (n=20). Neuromuscular blockade was monitored using train-of-four (TOF) stimulation by recording the contraction force of the adductor pollicis muscle with a muscle relaxation monitor. A bolus dose of cisatracurium of 0.15 mg/kg was administered to facilitate endotracheal intubation, followed by continuous infusion adjusted manually to maintain the first twitch (T1) < or = 5% of the control level. The following variables were recorded including the infusion rate, total amount of cisatracurium, spontaneous recovery index (RI), and the time interval from termination of infusion cisatracurium to recovery of TOF ratio (TOFR) to 0.9. RESULTS: With the maintenance of a 95%-99% neuromuscular blockade, the infusion rate was significantly lower in sevoflurane group than in propofol-remifentanil group (P<0.05), and stabilized in both groups after 120 min. No significant differences were found in RI or the time to TOFR of 0.9 between the two groups (P>0.05). CONCLUSION: During the maintenance of stable neuromuscular blockade by continuous cisatracurium infusion, both sevoflurane and propofol-remifentanil anesthesia can time-dependently enhance the effect of cisatracurium without producing significant differences in the recovery properties.

Glial cells are involved in the exciting effects of doxapram on brainstem slices in vitro.

This study tested whether the glial cells are involved in the exciting effects of doxapram on brainstem slice in vitro. Experiments were performed in brainstem slice preparations from neonatal rats. The medial area of nucleus retrofacialis (mNRF) and the hypoglossal nerve (XII nerve) were contained in the preparations. The slices were perfused with modified Kreb's solution (MKS), and the rhythmical respiratory discharge activity (RRDA) was simultaneously recorded from the XII nerve by using suction electrodes, including the discharge time course of inspiratory (Ti), expiratory (Te), respiratory cycle (RC), and integrity amplitude of inspiratory discharge (IA). After applying of doxapram (5 microM) to the MKS for 10 min, Ti and IA increased significantly (85.0 +/- 25.0%, 13.2 +/- 2.5%, respectively, P < 0.05), the Te and the RC decreased significantly (19.0 +/- 1.4%, 12.8 +/- 1.4%, respectively, P < 0.05) when compared with control group. When the methionine sulfoximine (MS, 10 microM), a blockage of glutamine synthetase, was applied, all the exciting effects of doxapram on RRDA were reversed. After the glutamine (20 microM) was applied to the MKS for 10 min, the exciting effects were revealed again. Our results suggest that the normal metabolism of glial cells takes a key role in the modification of the RRDA in the slices. In conclusion, glial cells are involved in the exciting effects of doxapram on brainstem slice in vitro.

[Effect of doxapram on the respiratory rhythmical discharge activity in the brainstem slice of neonatal rats].

OBJECTIVE: To investigate the effects of doxapram on the respiratory rhythmical discharge activity (RRDA) in the brainstem slices of neonatal rats. METHODS: Thirty neonatal SD rats (of either sex, 0-3 days old) were randomly divided into 6 equal groups (groups I-VI), and the brainstem slices which contained the medial region of the nucleus retrofacialis (mNRF) were prepared. All the slices were perfused with modified Kreb's solution (MKS), and in group I (control group), the slices were perfused with MKS only; in groups II to IV, the slices were perfused with doxapram in MKS continuously at the concentrations of 2, 5, and 10 micromol/L, respectively; in groups V and VI, the slices were perfused with 20 micromol/L propofol and 20 micromol/L propofol plus 5 micromol/L doxapram, respectively. The RRDA in the hypoglossal nerve was recorded by suction electrode. The discharge time course of the inspiratory (TI), expiratory (TE), respiratory cycle (RC) and integral amplitude of the inspiratory discharge (IA) were recorded at 1, 3, 5, 10, 15, and 30 min after the application of the drugs. RESULTS: The hypoglossal nerve in groups I, II and VI showed no significant changes of RRDA in the entire course of the experiment (P>0.05). In groups III and IV, the TI, IA increased and TE decreased significantly 5 min after doxapram application (P<0.05), and the RC was shortened only at 10 min. In group V, the TI and IA decreased and the RC and TE increased significantly after the drug application (P<0.05). CONCLUSION: Doxapram (>5 micromol/L ) can directly stimulate the RRDA and prevent propofol-induced inhibitory effects in the brainstem slice of neonatal rats, and the effects are mediated by its actions upon the inspiratory neurons in the mNRF.