The distribution of β₂-adrenergic receptors (β₂-ARs) in the rat spinal cord was investigated by immunocytochemistry using an antibody against .β₂-ARs. The relationship between .β₂-ARs and catecholaminergic terminals containing the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH), in the dorsal horn was also examined by light and electron microscopy. β₂-ARimmunoreactivity (β₂-AR-IR) showing the appearance of fibers and puncta was particularly dense in laminae I and II of the dorsal horn. Moderate immunoreactivity was observed in the intermediolateral cell column, in the ventral horn and around the central canal. Additional immunoreactivity was detected in ependyma lining the central canal. Capsaicin treatment reduced, but did not eliminate, the immunostaining in the dorsal horn. Double immunofluorescence histochemistry for, β₂-AR and TH showed no colocalization of the two antigens. By electron microscopy, β₂-AR-IR was found in dendrites as well as unmyelinated axons and axon terminals which contained many small clear vesicles and several large granular vesicles. Such terminals usually formed asymmetric synapses on labeled or unlabeled dendrites. TH-labeled terminals were often near both axonal and dendritic profiles containing β₂-AR-IR and sometimes made synaptic contacts with β₂-AR-labeled dendrites. However, .β₂-AR-IR was found on the extrasynaptic portion of the plasma membrane. No synaptic contact was made between TH-labeled terminals and β₂-AR-labeled varicosities. These results demonstrated that β₂-ARs are localized on both nociceptive primary afferents and on dendrites in the rat dorsal horn and provide the ultrastructural evidence that β₂-ARs on both axonal and dendritic profiles are activated by catecholamines released from catecholaminergic terminals via volume transmission.

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Effects of milnacipran (MIL), a serotonin and noradrenaline reuptake inhibitor (SNRI), on synaptic transmission were examined in the rat locus coeruleus (LC). Bath-application of MIL produced a hyperpolarization associated with a decrease in input resistance of LC neurons. The MIL-induced hyperpolarization reversed polarity near the equilibrium potential of K⁺. The MILinduced hyperpolarization was blocked by yohimbine (1μM). Clonidine, but not serotonin (5-hydroxytryptamine; 5-HT), produced a hyperpolarizing potential in LC neurons. The MIL-induced hyperpolarization reversed polarity at -114±3 mV (n=4). MIL (0.1-10μM) depressed the amplitude of the excitatory postsynaptic potential (EPSP), while it enhanced the amplitude and duration of the inhibitory postsynaptic potential (IPSP). These results suggest that MIL hyperpolarizes LC neurons and enhances the IPSP by increasing endogenous noradrenaline (NA) concentration at synapses in LC neurons.

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Glial cell line-derived neurotrophic factor (GDNF) was initially identified as a neurotrophic factor for dopaminergic neurons but its effects are not restricted to nervous tissue. It is reported that GDNF-induced intercellular signaling is necessary for the normal development of a variety of non-neural tissues. In this study, immunoreactivities of both GDNF and its functional receptor Ret were evaluated in normal adult rat sweat gland by light and electron microscopy. Ret was found in the epithelial cells of the excretory duct and the coiled secretory terminal of the sweat gland. Electron microscopic observation of the secretory epithelium showed that Ret immunoreactivity is localized in the basal area of the secretory cells, facing myoepithelial cells, but it was not observed in the basal infolding or in the apical region of these cells. On the other hand, GDNF was observed in most myoepithelial cells of the coiled secretory portion of the sweat gland and in a small number of nerve fibers innervating the gland. Although the GDNF-containing nerve fibers cannot be negated as a source of the ligand for Ret in the secretory cells, the finding that GDNF and Ret are localized face to face in adjoining cells in the sweat gland implies another novel trophic role of GDNF in this tissue.

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Aging societies have an increased incidence of fractures caused by osteoporosis.Vertebral compression fractures occur most frequently in the thoracolumbar vertebrae of elderly individuals. The severe pain caused by this type of fracture causes many patients to become bedridden. However, the initial pain generally diminishes after around 1 month and is replaced by dull pain in the lumbar and lumbosacral regions. We carried out a cross-sectional and longitudinal study of these fractures in 328 female outpatients with osteoporosis. All subjects initially presented at our hospital with back pain and bone mineral density measurements were taken using both dual energy X-ray absorptiometry and quantitative computed tomography. Our main findings were as follows. Decreased BMD appears to be one cause of vertebral body deformities. However, we found it difficult to predict whether deformities will progress or cause additional deformities of adjacent vertebral bodies, because the key contributing factors include not only BMD and age but also lifestyle and activity patterns. In addition, none of the drug administration methods investigated here resulted in a notable increase in BMD.

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In the present study we have examined the immunohistochemical expression of matrix metalloproteinases (MMPs) in bile duct cancer tissue and the relationship between MMP expression and various clinicopathologic factors. We performed immunohistochemical studies of matrix metalloproteinase-2 (MMP2), and matrix metalloproteinase-3 (MMP3). MMP2 and MMP3 were expressed in 48.9% (23/47) and 44.7% (21/47) of the subjects, respectively. Subjects positive for MMP2 showed significantly higher association rates of MMP3 expression than those who were not (p<0.05). MMP2 expression was also significantly higher in the group with histologically welldifferentiated lesions than in the group with poorly differentiated lesions (p<0.05). Expression of MM2 and MM3 was significantly higher in subjects with neural invasion (p<0.05). The MMP2-negative group had a significantly better prognosis than the MMP2-positive group (p<0.05). MMP2 expression tended to increase as the degree of differentiation decreased, and this indicated a possibility that MMP2 and MMP3 may be involved in the development of perineural invasion in bile duct cancer. Perineural invasion is an important prognostic factor in bile duct cancer, and the fact that various types of cytokines are involved in the activation of MMPs suggested that bile duct cancer complicated by obstructive cholangitis might be associated with a poorer prognosis.

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It has been proven that interleukin-15 (IL-15) has structural and functional features similar to those of interleukin-2 (IL-2). In this study we examined the anti-tumor effect of IL-15 using an adenoviral vector in a mouse model. We constructed an adenoviral vector expressing the IL-15 gene, and introduced it into a mouse Lewis lung carcinoma (LLC) cell line. Then we inoculated pulmonary tissue of a syngeneic mouse strain (C57BU6 CR) with the IL-15 gene-expressing LLC cells (LLC/IL-15). At the early phase (Day 14), a large number of NK cells accumulated around the IL-15 expressing tumors. At the late phase (Day 28), a much larger number of NK cells had accumulated around the tumors and quite a few NK cells had invaded the IL-15 expressing tumors. The LLC/IL-15-inoculated group survived significantly longer compared to the control groups, i.e., a group inoculated with LacZ gene-expressing LLC cells or a group inoculated with IL-2 gene-expressing LLC cells. After 60 days, the surviving mice of the LLC/IL-15-inoculated group were re-challenged with an additional inoculation of LLC cells alone. Tumor growth was significantly inhibited in the rechallenged LLC/IL-15 group. Induction of cytotoxic T cells was confirmed by interferon-γ production by splenocytes. We concluded that the IL-15 expressed in the IL-15 expressing tumor cells enhanced the accumulation of NK cells and activated them, leading to suppression of proliferation of the tumor cells.

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The purpose of this study was to evaluate the relationship between intimal hyperplasia and transforming growth factor-β1 (TGF-β1) mRNA expression in synthetic arterial grafts and also to clarify the effect of angiotensin-converting enzyme inhibitor (ACEI) on perianastomotic intimal hyperplasia and TGF-β1 mRNA expression. Thirty New Zealand White rabbits were randomly divided into two groups (15 each); one group was administered Captopril 10 mg/kg/day per os as an ACE inhibitor, and the other group received on saline as a vehicle from 7 days prior to operation until the graft was harvest (1, 8, or 14 weeks). A 10-mm segment of an expanded polytetrafluoroethylene graft (3 mm in diameter) was implanted in the right common carotid artery of the rabbits;15 rabbits had by-pass grafting alone (Graft Alone group) and the other 15 rabbits had by-pass graft along with the ACEI (Graft plus ACEI group). The artery grafts were harvested. The intima to media height ratio (IMHR) and the TGF-β1 mRNA expression level in perianastomotic graft tissue by reverse transcription-polymerase chain reaction (RT-PCR). The IMHRs gradually increased from 1 to 14 weeks in both groups (vs. 1 wk in each group, p<0.05). The IMHRs of the Graft plus ACEI group were comparable to those of Graft Alone group at 1 week, but significantly lower at 8 and 14 weeks (vs. Graft Alone group, p<0.05). The TGF-β1 mRNA expression levels of the Graft plus ACEI group were clearly lower than those of the Graft Alone group at 1 and 8 weeks (vs. Graft Alone group, p<0.05), but similar at 14 weeks. TGF-β1 in the synthetic artery graft of the Graft Alone group was up-regulated as early as 1 week after the operation, when no definitive development of a quantifiable neointima was observed. The TGF-β1 mRNA expression of the Graft Alone group was highest at 8 weeks and lowest at 14 weeks (vs. 1 week, ∗p<0.05), but such time-dependent changes were not observed in the Graft plus ACEI group. The results indicated that ACEI reduced intimal hyperplasia in the grafts of the Graft plus ACEI group and also suppressed TGF-β1 mRNA expression in perianastomotic intimal hyperplasia tissues to the normal artery level. Perianastomotic intimal hyperplasia in synthetic arterial graft is considered to be related to TGF-β1, the expression of which is locally mediated by angiotensin II and, therefore, suppressed by ACEI.

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We investigated whether a suspension technique of vesicourethral anastomosis with pubo-prostatic ligaments improved urinary continence following radical retropubic prostatectomy. The suspension of vesicourethral anastomosis was performed in 55 consecutive patients with clinically localized prostate cancer by placement of two stitches, which were anchored to pubo-prostatic ligaments preserving their anterior attachments to the pubic bone. Continence rates, positive rates of surgical margins, and complications in these patients after radical prostatectomy were compared with the results of 30 randomly selected patients in whom a suspension technique was not performed. There were no significant differences in the positive rates of either surgical margins or complications between these two groups. In contrast, continence rates in the suspension group at one and three months (75% and 89%) were significantly higher than those (13% [p<0.001 ] and 67% [p< 0.01]) of the control group. The suspension technique appears to have an advantage in immediate recovery of urinary continence following radical retropubic prostatectomy.

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For many years it was thought that lactic acid traverses plasma membranes by diffusion, however, it has been shown in recent years that lactic acid and other monocarboxylates are transported through these membranes together with H⁺ by monocarboxylate transporters (MCT5). Of these transporters, rat skeletal muscle has been found to contain MCT1 and MCT4. It is thought that MCT1 transports lactic acid into the skeletal muscle from outside the skeletal muscle cells, while MCT4 is involved in the extrusion of lactic acid out of the muscle cells. It has been reported that the concentration of MCT1 within the skeletal muscle is highest in muscle fibers with superior oxidative glycolytic capacity, whereas MCT4 concentrations are highest in fibers with greater anaerobic glycolytic capacity. However, the relation between MCT1 and MCT4 localization and muscle fiber type has not been clarified from a morphological viewpoint. The present study applied morphological methods to examine the relation between fiber type and localization of MCT1 and MCT4 in Wistar rat skeletal muscle. After the animals were perfusion-fixed in 4% paraformaldehyde, the extensor digitorum longus muscle (EDL) and the soleus muscle (SOL) were dissected out and MCT1 and MCT4 localization were immunohistochemically determined in serial sections. In addition, adjacent sections were immunohistochemically stained with parvalbumin to identify muscle fiber types. Results showed clearly that MCT1 was present on the plasma membranes of all type I fibers, whereas MCT4 was localized on the plasma membranes of all type Ilb fibers. Both MCT1 and MCT4 were found on nearly all intermediate type Ila fibers. The authors consider that these relationships between muscle fiber type and MCT1 or MCT4 localization reflect the differences in glycolytic metabolism that have been reported between the different muscle fiber types.

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Caveolae are a specific plasmalemmal microdomain which appear as flask-like invaginations and/or vesicles attaching just beneath the plasmalemma. Caveolae are present in many cell types and are found in the Schwann cells that ensheath myelinated and unmyelinated nerve fibers of the peripheral nervous tissues. However, the precise distribution in the Schwann cell plasmalemma and the functional properties of these caveolae remains obscure. The present study revealed:(1) Caveolae are most commonly observed in the Schwann cell plasmalemma of myelinated nerve fibers.(2) Caveolae are principally located in the perikaryal plasmalemma of Schwann cells of the myelinated nerves.(3) Caveolin-1 is expressed strongly in Schwann cell caveolae.(4) Caveolin 2 and 3 are also immunohistochemically detected in Schwann cell caveolae, although the immunoreactivities are slight. The results suggested that caveolae of the peripheral nervous system are involved in cellular activities specific to Schwann cells in myelinated nerve fibers. These caveolae may contain receptors for signaling molecules that could affect the myelinated nerve fibers, and/or proteins related to ion transfer activity. Further studies are necessary in order to clarify the types of proteins associated with Schwann cell caveolae.

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We report a 4-month-old female infant who developed West syndrome eleven days after administration of a histamine H₁ antagonist, oxatomide, for atopic dermatitis. It has been reported that some histamine H₁ antagonists induce seizures in epileptic patients. The age, the interval between oxatomide administration, and the onset of West syndrome and its clinical course were similar to two previously reported 3-month-old infants with West syndrome associated with ketotifen administration. We should be cautious in using the histamine H₁ antagonists, oxatomide and ketotifen, in young infants because such agents could potentially disturb the anticonvulsive central histaminergic system.

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We performed curettage followed by autogenous bone grafting in several cases of steroid-related osteonecrosis of the femoral condyle, and reviewed the outcome of this procedure after a mean follow-up of 9.5 years. The number of patients was 4; the mean age at the time of the operation was 30.5 years. The mean Knee Society Objective Score was 52.5 before the operation and had increased to 87.5 at the time of the review. The pre-operative radiographic stages were stage 2 in 2 patients and stage 3 in the other 2 patients. Progression in the disease stage was observed in 3 patients. MRI revealed survival of the grafted bone in only one case, and collapse of the articular surface in all cases. In conclusion, though the clinical results showed improvement, the autogenous bone graft failed to answer the purpose of preventing the progression in disease stage.

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A 63-year-old man was admitted with a complaint of dyspnea. Echocardiography showed severe aortic regurgitation (AR), and moderate mitral regurgitation (MR). Coronary angiography revealed that the right coronary artery (RCA) arose from the ascending aorta with a high takeoff and a significant stenosis at the distal segment of the RCA. Scintigraphy with Thallium showed a transient perfusion defect on the inferior wall. The diagnosis of AR and MR associated with anomalous origin of the RCA and myocardial ischemia was made. After successful catheter intervention for stenosis of the RCA, an operation was performed on the aortic and mitral valve. At surgery, the orifice of the RCA was located above the commissure of the right and left coronary cusps and the shape was obliquely elliptical. The RCA originated at an acute angle from the ascending aorta, and its proximal segment was incorporated in the wall of the aorta. After aortic valve replacement and mitral valve repair, a neo-ostium without unroofing of the intramural segment of the RCA was created at the proximal RCA, and the intima of the RCA was fixed to the intima of the aorta. The patient recovered uneventfully and is doing well without findings of myocardial ischemia at present 40 months after operation.

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Anal sphincteric resection for rectal cancer is most commonly followed by colostomy in the lower abdominal wall, which enforces quite a poor quality of life due to a permanent stoma. For surgeons treating lower rectal cancer, the goal is to achieve defecation via the anus without placing a stoma. Internal sphincteric resection, partial external sphincteric resection and coloanal anastomosis have been reported for the treatment of lower rectal cancer with avoiding a colostoma. Extended resection of the external sphincter, however, limits patient's daily activities because of poor functional results and necessitates reconstruction of damaged anal function. This paper describes a case of graciloplasty for postoperative anal dysfunction that yielded a good clinical outcome in a 65-year-old female who had undergone very low anterior resection with complete internal and partial external sphincteric resection for lower rectal cancer.

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