Antinociceptive effect of intrathecal administration of taurine in rat models of neuropathic pain

Purpose

Taurine is the most abundant amino acid in many tissues. Although taurine has been shown to be antinociceptive, in this report, our focus is to elucidate the mechanism and action site on neuropathic pain. This study used behavioural assessments to determine whether taurine attenuates neuropathic pain in the spinal cord.

Methods

Chronic constriction injury (CCI) to the sciatic nerve and streptozotocin-induced diabetic neuropathy were introduced to male Sprague-Dawley rats. We then assessed the antinociceptive effect of spinal injections of taurine (100, 200, 400, or 800 μg) using electronic von Frey, paw pressure, and plantar tests. To explore the effect of taurine on motor function, a rotarod test was performed, and in order to determine which neurotransmitter pathway is involved in taurine’s action, we examined how several antagonists of spinal pain processing receptors altered the effect of taurine 400 μg in a paw pressure test.

Results

Taurine alleviated mechanical allodynia, mechanical hyperalgesia, and thermal hyperalgesia in CCI rats and suppressed mechanical allodynia and hyperalgesia in diabetic rats. Significant effects were observed at 200 μg in both models. On the other hand, taurine dose-dependently affected motor performance, and a significant effect was seen at 400 μg. The antinociceptive effects were reversed completely by pretreatment with an intrathecal injection of strychnine, a glycine receptor antagonist.

Conclusion

The present study demonstrated that intrathecal administration of taurine attenuates different models of neuropathic pain, and these effects seem to be mediated by the activation of glycinergic neurotransmission. These findings suggest that taurine may be a candidate remedy for neuropathic pain.     

Risk factors for falls and fractures at night in relation to lower urinary tract symptoms: a survey of outpatients and inpatients at a general hospital

We investigated potential risk factors, including factors related to lower urinary tract symptoms (LUTS), for falls and fractures at night among outpatients and inpatients in a general hospital, via a questionnaire. The questionnaire included items to record the age, sex, number of consulting doctors, history of 11 particular medical diseases, LUTS, sleep, and falls and fractures at night. We distributed the questionnaire to 1,334 patients 51 years old or older in our hospital. Of the questionnaires completed, 96.9% were valid for analysis. Multivariate analyses revealed that "drinking water before bedtime or while in bed" was the strongest risk factor (odds ratio＝7.499) for bone fractures while "postural syncope" was the strongest risk factor (odds ratio＝5.041, except past medical history) for falls. In terms of LUTS, urge incontinence was a significant risk factor for falls.     

Combined hepatic resection with the inferior vena cava and diaphragm and reconstruction using an equine pericardial patch: Report of a case

We herein report a case of combined hepatic resection with inferior vena cava (IVC) and diaphragm resection, and reconstruction using an equine pericardial patch. A 54-year-old woman showed hepatic cancer recurrence on radiological imaging, with invasion to the caudate lobe of the liver, IVC, diaphragm, and adrenal gland. We resected 10 × 5 cm of the diaphragm. After dissecting the hepatic parenchyma, the caudate lobe was connected only to the IVC. Clamping of the IVC was performed between the IVC below the confluence of the hepatic vein and the suprarenal IVC. A 6 × 3-cm segment of the IVC was then resected. The IVC and diaphragm were reconstructed using an equine pericardial patch, as both defects were too large to repair without a patch. The equine pericardium represents a suitable graft material for repairing both the IVC and diaphragm. Further investigation is needed to determine the durability and anti-infection properties of equine pericardial grafts.     

Ruptured thoracic aortic aneurysm complicated by acute aortic dissection and aortic valve regurgitation; report of a case

An 87-year-old man was found loss of consciousness after falling. He was found in a state of shock. Computed tomography showed rupture of aneurysm of the ascending aorta and aortic arch with acute aortic dissection. Echocardiography revealed aortic valve regurgitation and cardiac tamponade. As the result of emergency operation, a large hematoma in the mediastinum and pleural cavity as well as massive serous pericardial effusion were found. The dissection was seen in aneurysm of the ascending aorta and aortic arch with an intimal tear located in the aortic arch. After aortic valve replacement was performed, the ascending aorta and aortic arch were replaced, and reconstruction of 3 cervical vessel branches was performed under deep hypothermic circulatory arrest with selective cerebral perfusion. Despite the complex clinical state and serious condition in the elderly patient, emergency surgery saved the life of the patient without complications.     

Venous sac embolization of pulmonary arteriovenous malformation: Preliminary experience using interlocking detachable coils

Purpose: To evaluate the indication and advantages of venous sac embolization of pulmonary arteriovenous malformations (PAVMs) using interlocking detachable coils (IDCs). Methods: We performed percutaneous embolization in 12 PAVMs in four patients using IDCs, initially placed in the venous sac or at the feeding artery to prevent systemic migration of additional coils. We placed the IDCs in the venous sac in PAVMs with the following vascular architecture: the draining vein was larger than the feeding arteries and both vessels were interposed with the venous sac or there were short feeding arteries. Results: Complete occlusion was achieved in all 12 PAVMs without significant complications. We deployed IDCs in the venous sac in eight PAVMs and in the feeding artery in four. Conclusion: Venous sac embolization may be beneficial in PAVMs with large out-flow vessels or short feeding arteries. IDCs are suitable for this procedure.     

Cardiac anesthesia induction by low target plasma concentration setting of propofol using target-controlled infusion

BACKGROUND: Propofol-anesthesia administerd using target-controlled infusion (TCI) has been proposed for cardiac surgery. But, moderate target concentration of propofol during induction using TCI has not been studied in detail. METHODS: Thirty patients scheduled for cardiac surgery under cardiopulmonary bypass (CPB) and TCI propofol anesthesia were randomly divided into two groups to receive a computer-controlled infusion of propofol with target concentrations of 1.5 or 2.0 micro/g x ml(-1) [1.5 microg x ml(-1) group (n=15) and 2.0 microg x ml(-1) group (n=15)]. Mean arterial pressure (MAP), heart rate (HR) and bispectral index scale (BIS) values were recorded at 5 time points during induction of anesthesia. RESULTS: MAP was significantly lower in 2.0 microg x ml(-1) group compared with 1.5 microg x ml(-1) group. In both groups, a rise of BIS value did not occur during tracheal intubation. CONCLUSIONS: We have demonstrated that propofol TCI at a target concentration of 1.5 microg x ml(-1) is effective for hemodynamic stability during induction of anesthesia in patients for cardiac surgery under CPB.     

Value of Multidetector-row Computed Tomography in Diagnosis of Portal Vein Invasion by Perihilar Cholangiocarcinoma

BACKGROUND: Although knowledge of cancer invasion of the portal bifurcation is vitally important in planning an operation for perihilar cholangiocarcinoma, the diagnostic capability of multidetector-row computed tomography (MDCT) for this purpose has not been assessed. We evaluated how well MDCT could identify cancer invasion of the portal bifurcation by perihilar cholangiocarcinoma. METHODS: Between April 2003 and June 2005, perihilar cholangiocarcinoma was resected in 87 patients, 83 of whom underwent MDCT within 1 month before the surgery. Three-dimensional volume-rendered (3DVR) and multiplanar reformation (MPR) images were examined for evidence of portal vein invasion. Agreement with intraoperative and pathologic findings was assessed. Portal bifurcation findings by 3DVR and MPR were classified into no portal vein stenosis, unilateral stenosis, or more extensive stenosis, and also into tumor contact with the bifurcation in no, one of two, or two projections. RESULTS: For macroscopic portal vein invasion, sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were 81.5, 91.1, 81.5, 91.1, and 88.0% in 3D portography and 96.3, 92.6, 86.7, 98.1, and 94.0% in MPR, respectively. Findings by both 3DVR and MPR were significantly correlated with depth of cancer invasion (p < 0.001). CONCLUSION: MDCT is useful in assessing cancer invasion of the portal vein bifurcation by perihilar cholangiocarcinoma.     

Comparison of the effects of aortic valve replacement using 19-mm Carpentier-Edwards Perimount bioprosthesis and 19-mm Medtronic Mosaic bioprosthesis.

OBJECTIVE: Short (< or =3 months)- and middle (> or =4 months)-term results of aortic valve replacement (AVR) using 19-mm Carpentier-Edwards Perimount (CEP) bioprosthetic valves and 19-mm Medtronic Mosaic (MM) bioprosthetic valves in patients with small aortic annulus were compared. PATIENTS AND METHODS: At our facility, AVR was performed using bioprostheses in 110 patients from April 1999 to March 2006. Of these patients, 40 were treated using 19-mm CEP (Group C), and 9 using 19-mm MM (Group M). Evaluation by inquiry, physical examination, and echocardiography was performed before, a short term after, and a middle term after surgery, and the effects of AVR were compared. RESULTS: The New York Heart Association (NYHA) functional class grade showed improvements in both groups. The aortic valve peak pressure gradient was 29.8 +/- 10.1 mmHg in Group C and 53.8 +/- 17.3 mmHg in Group M, being higher in Group M, a middle term after surgery. However, the left ventricular mass index (LVMI) showed improvements in both groups compared with the values before surgery, and the left ventricular ejection fraction (LVEF) was maintained. During the middle term after surgery, the frequency of cardiac events showed no significant difference between the two groups. CONCLUSIONS: In the patients treated with 19-mm MM, the aortic valve peak pressure gradient was higher than in those treated with 19-mm CEP, but acceptable improvements in the LVMI, maintenance of the LVEF, and avoidance of cardiac events were observed in both groups.