Prostaglandin E Receptor Subtypes EP2 and EP4 Promote TH1 Cell Differentiation and TH17 Cell Expansion Through Different Signaling Modules

It is well known that prostaglandin (PG) E₂ exerts T cell suppression in vitro through elevating cAMP by its receptors, EP2 and EP4. However, such an action is rarely detected in vivo, leaving PGE₂-mediated immunosuppression an enigma. Here we show that under strong TCR stimulation, PGE₂ facilitates T helper-1 (T_H-1) differentiation through activation of phosphatidylinositol-3-kinase (PI3K) by EP2 and EP4. The PGE₂-EP4 signaling is also required for IL-23 production by activated dendritic cells (DCs), and the PGE2-EP2/EP4 signaling amplifies IL-23-mediated T_H-17 cell expansion. Administration of an EP4-selective antagonist in vivo to mice subjected to experimental allergic encephalomyelitis (EAE) decreases accumulation of both T_H-1 and T_H-17 cells in regional lymph nodes, and suppresses the disease progression. These results suggest PGE₂ promotes immune inflammation through T_H-1 differentiation and T_H-17 expansion and the EP4 antagonism is therapeutically useful for various immune diseases.

     

Associations between serum lipoprotein(a) levels and the severity of coronary and aortic atherosclerosis

To elucidate the associations between Lp(a) levels and coronary and aortic atherosclerosis, we performed aortic MRI in 143 patients undergoing coronary angiography. Severity of aortic atherosclerosis was represented as plaque scores. Of the 143 patients, 104 had coronary artery disease (CAD). Thoracic and abdominal aortic plaques were found in 89 and 131 patients. Lp(a) levels increased stepwise with the number of stenotic coronary vessels: 15.7 (CAD(-)), 21.2 (1-vessel), 21.4 (2-vessel), and 22.9 mg/dl (3-vessel) (P<0.05). For aortic atherosclerosis, 143 patients were divided into quartiles by plaque scores. Lp(a) did not differ among quartiles of thoracic plaques: 17.1, 19.0, 23.5, and 21.2 mg/dl (P=NS), whereas Lp(a) increased stepwise with quartiles of abdominal plaques: 17.1, 19.2, 19.1, and 24.0 mg/dl (P<0.05). Lp(a) was an independent factor for CAD and abdominal aortic plaques, but not thoracic plaques. Thus, Lp(a) levels were associated with aortic atherosclerosis, especially in abdominal aorta, as well as coronary atherosclerosis.     

Impact of Less Invasive Treatments Including Sclerotherapy With a New Agent and Hemorrhoidopexy for Prolapsing Internal Hemorrhoids

Conventional hemorrhoidectomy is applied for the treatment of prolapsing internal hemorrhoids. Recently, less-invasive treatments such as sclerotherapy using aluminum potassium sulphate/tannic acid (ALTA) and a procedure for prolapse and hemorrhoids (PPH) have been introduced. We compared the results of sclerotherapy with ALTA and an improved type of PPH03 with those of hemorrhoidectomy. Between January 2006 and March 2009, we performed hemorrhoidectomy in 464 patients, ALTA in 940 patients, and PPH in 148 patients with second- and third-degree internal hemorrhoids according to the Goligher''s classification. The volume of ALTA injected into a hemorrhoid was 7.3 ± 2.2 (mean ± SD) mL. The duration of the operation was significantly shorter in ALTA (13 ± 2 minutes) than in hemorrhoidectomy (43 ± 5 minutes) or PPH (32 ± 12 minutes). Postoperative pain, requiring intravenous pain medications, occurred in 65 cases (14%) in hemorrhoidectomy, in 16 cases (1.7%) in ALTA, and in 1 case (0.7%) in PPH. The disappearance rates of prolapse were 100% in hemorrhoidectomy, 96% in ALTA, and 98.6% in PPH. ALTA can be performed on an outpatient basis without any severe pain or complication, and PPH is a useful alternative treatment with less pain. Less-invasive treatments are beneficial when performed with care to avoid complications.     

3D Computer graphics simulation to obtain optimal surgical exposure during microvascular decompression of the glossopharyngeal nerve

The affected artery in glossopharyngeal neuralgia (GPN) is most often the posterior inferior cerebellar artery (PICA) from the caudal side or the anterior inferior cerebellar artery (AICA) from the rostral side. This technical report describes two representative cases of GPN, one with PICA as the affected artery and the other with AICA, and demonstrates the optimal approach for each affected artery. We used 3D computer graphics (3D CG) simulation to consider the ideal transposition of the affected artery in any position and approach. Subsequently, we performed microvascular decompression (MVD) surgery based on this simulation. For PICA, we used the transcondylar fossa approach in the lateral recumbent position, very close to the prone position, with the patient’s head tilted anteriorly for caudal transposition of PICA. In contrast, for AICA, we adopted a lateral suboccipital approach with opening of the lateral cerebellomedullary fissure, to visualize better the root entry zone of the glossopharyngeal nerve and to obtain a wide working space in the cerebellomedullary cistern, for rostral transposition of AICA. Both procedures were performed successfully. The best surgical approach for MVD in patients with GPN is contingent on the affected artery—PICA or AICA. 3D CG simulation provides tailored approach for MVD of the glossopharyngeal nerve, thereby ensuring optimal surgical exposure.