Analgesic Effects of Duloxetine on Formalin-Induced Hyperalgesia and Its Underlying Mechanisms in the CeA.

In rodents, the amygdala has been proposed to serve as a key center for the nociceptive perception. Previous studies have shown that extracellular signal-regulated kinase (ERK) signaling cascade in the central nucleus of amygdala (CeA) played a functional role in inflammation-induced peripheral hypersensitivity. Duloxetine (DUL), a serotonin and noradrenaline reuptake inhibitor, produced analgesia on formalin-induced spontaneous pain behaviors. However, it is still unclear whether single DUL pretreatment influences formalin-induced hypersensitivity and what is the underlying mechanism. In the current study, we revealed that systemic pretreatment with DUL not only dose-dependently suppressed the spontaneous pain behaviors, but also relieved mechanical and thermal hypersensitivity induced by formalin hindpaw injection. Consistent with the analgesic effects of DUL on the pain behaviors, the expressions of Fos and pERK that were used to check the neuronal activities in the spinal cord and CeA were also dose-dependently reduced following DUL pretreatment. Meanwhile, no emotional aversive behaviors were observed at 24 h after formalin injection. The concentration of 5-HT in the CeA was correlated with the dose of DUL in a positive manner at 24 h after formalin injection. Direct injecting 5-HT into the CeA suppressed both the spontaneous pain behaviors and hyperalgesia induced by formalin injection. However, DUL did not have protective effects on the formalin-induced edema of hindpaw. In sum, the activation of CeA neurons may account for the transition from acute pain to long-term hyperalgesia after formalin injection. DUL may produce potent analgesic effects on the hyperalgesia and decrease the expressions of p-ERK through increasing the concentration of serotonin in the CeA.

IR Spectra of Different O2-Content Hemoglobin from Computational Study: Promising Detector of Hemoglobin Variant in Medical Diagnosis.

IR spectra of heme and different O2-content hemoglobin were studied by the quantum computation method at the molecule level. IR spectra of heme and different O2-content hemoglobin were quantificationally characterized from 0 to 100 THz. The IR spectra of oxy-heme and de-oxy-heme are obviously different at the frequency regions of 9.08-9.48, 38.38-39.78, 50.46-50.82, and 89.04-91.00 THz. At 24.72 THz, there exists the absorption peak for oxy-heme, whereas there is not the absorption peak for de-oxy-heme. Whether the heme contains Fe-O-O bond or not has the great influence on its IR spectra and vibration intensities of functional groups in the mid-infrared area. The IR adsorption peak shape changes hardly for different O2-content hemoglobin. However, there exist three frequency regions corresponding to the large change of IR adsorption intensities for containing-O2 hemoglobin in comparison with de-oxy-hemoglobin, which are 11.08-15.93, 44.70-50.22, and 88.00-96.68 THz regions, respectively. The most differential values with IR intensity of different O2-content hemoglobin all exceed 1.0 × 104 L mol-1 cm-1. With the increase of oxygen content, the absorption peak appears in the high-frequency region for the containing-O2 hemoglobin in comparison with de-oxy-hemoglobin. The more the O2-content is, the greater the absorption peak is at the high-frequency region. The IR spectra of different O2-content hemoglobin are so obviously different in the mid-infrared region that it is very easy to distinguish the hemoglobin variant by means of IR spectra detector. IR spectra of hemoglobin from quantum computation can provide scientific basis and specific identification of hemoglobin variant resulting from different O2 contents in medical diagnosis.

[Effects of glutamine-enriched enteral nutrition on nutritional status and prognosis of patients with severe head injury].

OBJECTIVE: To investigate the effects of glutamine-enriched enteral nutrition on the nutritional status and prognosis of patients with severe head injury. METHODS: Thirty-three patients with severe head injury were randomly divided into control group (C, 15 cases) and glutamine-enriched group (Gln, 18 cases). Patients in both groups were given routine treatment and enteral nutrition with the same amount of nitrogen and calorie. Patients in Gln group were given glutamine 0.5 g x kg(-1) x d(-1) additionally added into the nutrient fluid. Vital signs and the occurrence of side effects of all patients were observed before and after nutrition support. Venous blood and urine sample of all patients were collected before and 7, 14 days after treatment to determine the parameters of blood, urine routine and hepatorenal function. At the same time points, body mass, skin fold thickness at the region of triceps brachii (TSF), upper arm circumference (AC), upper arm muscle circumference (AMC) and fasting blood glucose of all patients were detected and determined, Glasgow coma scale (GCS) scoring was performed. The length of hospital stay of all patients was recorded. RESULTS: Vital signs and parameters of blood, urine routine and hepatorenal function of patients in 2 groups after nutrition treatment were close to those before treatment. Side effects, such as nausea and diarrhea occurred with spontaneous remission in a few patients. There was no statistical significant difference between 2 groups, and within each group before and after treatment, in respect of body mass and TSF (P > 0.05). Values of AC and AMC of patients in Gln group were obviously higher than those of C group (P < 0.01) on post-treatment day 14. Fasting blood glucose and GCS score of all patients before treatment were close to those on post-treatment day 14 (P > 0.05). Fasting blood glucose and GCS score of patients was respectively lower and higher in Gln group than that in C group on post-treatment day 7 (P < 0.05). Length of hospital stay of patients in Gln group (25 +/- 9) d was obviously shorter than that of C group (33 +/- 12) d (P < 0.05). CONCLUSIONS: Glutamine-enriched enteral nutrition can control the blood glucose level, prevent the loss of lean tissue, improve nutrition status of patients,shorten hospital stay, and accelerate the recovery of patients to some extent.

[Expressions of CD31 and vWF in arachnoid villus endothelium cell from experimental animal with Hydrocephalus].

OBJECTIVE: The aim of this study was to investigate the CD-31 and vonWillebrand factor (vWF) expressions and the cell morphological alterations ofarachnoid villus endothelium in different stages of animal hydrocephalus. METHODS: Silicon oil was injected into the fourth ventricle of experimental canine for buildinghydrocephalus model. The post-injection ethology of the canine was observed, and thescoring of Tarlov n was performed. The magnetic resonance (MR) images of canineskulls were achieved for verification of hydrocephalus at 3 day, 2 weeks, and 12 Cweeks post-injection. The expressions of CD-31 and von Willebrand factor (vWF) inthe arachnoid villus endothelium cells at different stages of hydrocephalus werestudied by immunofluorescence histochemistry. RESULTS: Experimental hydrocephalusanimal model was built up satisfactorily by injection of silicon oil. Experimentalcanines appeared the hydrocephalus symptoms and Tarlov scoring decrease. MRimages revealed progressive ventricular enlargement in different stages ofhydrocephalus. The immunofluorescence histochemistry staining showed that CD31 expressed positively in all the endothelium cells, including the endothelium cell of thevillus. The immunofluorescence histochemistry staining showed that the vWFexpression in the endothelium of the villus was diminished when compared to that innormal sinus wall. And in sub-acute and chronic hydrocephalus, the expression of vonWillebrand factor increased. CONCLUSIONS: The fourth ventricular injection of siliconoil may induce the hydrocephalus animal model. The expression of von Willebrandfactor in the endothelium cell of arachnoid villus increases during progressedhydrocephalus.

[Expression and clinical significance of cyclooxygenase-2 in medulloblastoma].

OBJECTIVE: To gain an insight into the possible relationship between the expression of cyclooxygenase-2 (COX-2) and the prognosis of the patients with medulloblastoma. METHODS: COX-2 expression was investigated in 52 medulloblastoma and 10 normal cerebellar tissue specimens by immunohistochemistry. Kaplan-Meier analyses, Log-rank test, and Cox proportional hazard model were used to explore the relationship between the percentage of COX-2 expression and the survival period of patients with medulloblastoma. RESULTS: Positive staining with COX-2 was either moderately or strongly observed in most of the medulloblastoma (51/52). Moreover, COX-2 was expressed not only in tumor cells, but also in the vascular endothelial cells of tumor. No COX-2 immunoreactivity was observed in normal cerebellar tissue. Kaplan-Meier analyses demonstrated that high COX-2 expression (> or = 50% of cells stained positive) correlated with poor survival for the study group as a whole (P < 0.0001). CONCLUSION: Our study provides evidence that COX-2 is expressed in the majority of medulloblastomas and that a potential role of COX-2 inhibitors as an adjuvant therapy for brain tumors may exist.

[Determination of creatine, phosphocreatine and adenosinephosphates in experimental hydrocephalus tissue by reversed-phase high performance liquid chromatography].

OBJECTIVE: To investigate the state of impaired cerebral energy metabolism of the hydrocephalus tissue. METHODS: Adult male dogs were used for establishing the model of kaolin-induced hydrocephalus. A simple and rapid method for the simultaneous determination of creatine (Cr), phosphocreatine (Crp), and adenosinephosphates (AMP, ADP, ATP) in different stages of experimental hydrocephalus tissue by reversed-phase high performance liquid chromatography (RP-HPLC) has been established. The chromatographic conditions were as follows: Inertsil ODS-3 C18 column (4.6 mm x 250 mm i.d. 5 microns), the mobile phase being composed of KH2PO4 buffer (330 mmol/L)-acetonitrile-TBA (45 mmol/L) (94:5.5:0.5) (pH = 6.27) and detector at 210 nm. RESULTS: The calibration curve showed a good linearity in the mass concentration range of 5.69-3640.50 mumol/L (r = 0.9993) for Cr, 3.47-555.50 mumol/L (r = 0.9999) for Crp, 2.69-1723.00 mumol/L (r = 0.9993) for AMP, 2.66-1704.00 mumol/L (r = 0.9999) for ADP and 2.94-1883.50 mumol/L (r = 0.9999) for ATP. The recoveries ranged from 90.10% to 107.00% with relative standard deviations from 1.58% to 3.88%. The detection limits of this method were 3.55-5.84 mumol/L. By means of this method, the Cr, Crp, AMP, ADP and ATP in different stages of 16 dogs experimental hydrocephalus tissue were determined with satisfactory results. CONCLUSION: This method is rapid, precise, accurate and suitable for the determination of the high energy nucleotides in hydrocephalus tissues.