Contactless electrical conductivity measurement of metallic submicron-grain material: Application to the study of aluminum with severe plastic deformation.

We measured the electrical conductivity σ of aluminum specimen consisting of submicron-grains by observing the AC magnetic susceptibility resulting from the eddy current. By using a commercial platform for magnetic measurement, contactless measurement of the relative electrical conductivity σn of a nonmagnetic metal is possible over a wide temperature (T) range. By referring to σ at room temperature, obtained by the four-terminal method, σn(T) was transformed into σ(T). This approach is useful for cylinder specimens, in which the estimation of the radius and/or volume is difficult. An experiment in which aluminum underwent accumulative roll bonding, which is a severe plastic deformation process, validated this method of evaluating σ as a function of the fraction of high-angle grain boundaries.

UFT and mitomycin plus tamoxifen for stage II, ER-positive breast cancer. Hokkaido ACETBC Study Group.

A trial was designed to examine the combination of UFT and mitomycin (Mutamycin) plus tamoxifen (Nolvadex) as postoperative adjuvant therapy in the treatment of patients with stage II, estrogen receptor (ER)-positive primary breast cancer. Mitomycin was administered intravenously at 13 mg/m2 on the day of surgery. Patients judged to be ER-positive were randomly allocated to either group A, which received oral tamoxifen 20 mg/day 14 days after surgery for 2 years, or group B, receiving oral UFT 400 mg/day plus tamoxifen 20 mg/day. A total of 219 patients were enrolled in group A, of which 213 (97.3%) were determined to be eligible; 225 patients enrolled in group B and 223 (99.1%) were eligible. The 5-year survival rates were 93.0% for group A and 95.4% for group B, with no significant difference between groups. The 5-year relapse-free survival rates were 83.1% for group A and 90.7% for group B, a significant advantage (P = .020) for the UFT plus tamoxifen group. Combination therapy with mitomycin, tamoxifen, and UFT proved to be an effective postoperative chemoendocrine therapy for stage II, ER-positive breast cancer.

Allogeneic hepatocyte transplantation: contribution of Fas-Fas ligand interaction to allogeneic hepatocyte rejection.

Hepatocyte transplantation is a potential therapeutic modality for overcoming the shortage of liver donors, and the clinical application of allogeneic hepatocyte transplantation has been considered. However, there are two major problems with allogeneic hepatocyte transplantation: protection of transplanted hepatocytes from rejection and stimulation of the rapid proliferation of surviving cells. Without immunosuppression, allogeneic hepatocytes are rapidly rejected within a few days after transplantation, even though it is relatively easy to induce immunotolerance after allogeneic whole liver transplantation. Accordingly, different rejection mechanisms seem to operate after allogeneic hepatocyte transplantation and whole liver transplantation. To overcome the rejection of transplanted hepatocytes, induction of donor-specific unresponsiveness to graft without compromising the host immune system would be ideal. We previously reported that the Fas-Fas ligand system plays a critical role in the CD28-independent pathway of hepatocyte rejection. Therefore, blockade of rejection using CTLA4 immunoglobulin (CTLA4Ig) or anti-CD80/86 monoclonal antibodies and anti-FasL monoclonal antibody may prolong the survival of transplanted allogeneic hepatocytes. Furthermore, administration of hepatocyte growth factor (HGF) can promote the proliferation of allogeneic hepatocytes and this may lead to the development of a functioning liver substitute.

Critical role of Fas/Fas ligand interaction in CD28-independent pathway of allogeneic murine hepatocyte rejection.

Cytolytic induction of T cells requires both the T-cell receptor (TCR)-mediated antigenic stimulation and the CD28-mediated co-stimulatory signal. Blockade of the interactions between CD28 and its ligands, CD80 and CD86, prolongs the survival of allografts in some transplantation models. However, we found that allogeneic hepatocytes were completely rejected within 7 days after intrasplenic transplantation, even when treated with monoclonal antibodies (mAbs) against CD80 and CD86 (anti-CD80/86). Recent studies have shown that there are two main mechanisms of T-cell-mediated cytotoxicity, perforin-based and Fas-based ones. It has been shown that the liver is highly sensitive to induction of apoptosis by an agonistic anti-Fas mAb. We then investigated the role of the Fas/Fas ligand (FasL) system in the CD28-independent allogeneic hepatocyte rejection. With the anti-CD80/86 mAb treatment, hepatocytes from C57BL/6 lpr/lpr (B6 lpr) mice, which express little Fas antigen, could survive for 7 days after intrasplenic transplantation, and hepatocytes from C57BL/6 (B6) mice could also survive for 7 days in the spleen of C3H/ He gld/gld (C3H gld) mice, which express no functional FasL. CD28-independent induction of cytotoxicity against allogeneic hepatocytes was not observed when the effector cells were derived from C3H gld mice. These results indicated that the Fas/FasL system plays a critical role in the CD28-independent pathway of allogeneic hepatocyte rejection.

Successful treatment of a rectal anastomotic stenosis by transanal endoscopic microsurgery (TEM) using the contact Nd:YAG laser.

We report the advantage of employing transanal endoscopic microsurgery (TEM) using the contact Nd:YAG laser for the treatment of a rectal anastomotic stenosis. A 72-year-old woman was admitted to our hospital with a postoperative rectal anastomotic stenosis. Twenty months prior to admission, the patient underwent a low anterior resection for the treatment of the rectal cancer using an EEA stapling device. A barium enema and colonoscopy revealed a rectal stenosis, 0.8-cm diameter. This stenosis was at the anastomotic site, approximately 4.0 from the dental line. An endoscopic treatment was performed transanally using the contact Nd:YAG laser. The stenotic rectal wall was fulgurated or vaporized completely. There were no intraoperative or postoperative complications. We concluded that TEM appears to be a safe and minimally invasive procedure. Furthermore, the contact Nd:YAG laser is very effective in treating the gastrointestinal stenotic area. To our knowledge, this is the first successful report of this novel procedure.

Orthotopic transplantation of a partial hepatic autograft in dogs.

The purpose of this study was to investigate the availability of an orthotopic transplantation of partial hepatic autograft in dogs as a means of surgical training. Male mongrel dogs weighting 10-15 kg were used. The left lobe of the liver was harvested while preserving the left branches of the portal vein, hepatic artery and bile duct, and the left hepatic vein. The remnant liver was removed while preserving the inferior vena cava using a veno-venous bypass. Orthotopic transplantation of the autograft was performed while anastomosing the left hepatic vein to the inferior vena cava, portal and arterial reconstruction, and external biliary drainage. Thirteen out of 29 dogs survived more than 48 h after transplantation. However, 6 out of 13 dogs were sacrificed after developing bile peritonitis due to a dislodgement of the biliary catheter, and only two dogs were able to survive for 7 days after transplantation. The arterial ketone body ratio recovered to 1.0 within 1 h after reperfusion, and the ratio of the dogs that survived for more than 48 h remained above 1.0 until sacrifice. Orthotopic transplantation of a partial hepatic autograft is a useful and simple procedure to train surgeons for partial liver transplantation.

A new trocar approach insertion site for laparoscopic surgery: the xiphoidal approach.

Laparoscopic cholecystectomy (LC) has become the standard treatment for removing a diseased gallbladder. Endoscopic surgical techniques are used to perform appendectomies, bowel resections, and gastrectomies. This minimally invasive surgery is favored because it decreases the patients' postoperative pain and length of hospitalization. However the incidence of complications with this technique is not negligible. As a new technique is evolving, the potential for complications is high. This increase in complication rate is undoubtedly due to inexperience during the initial phase of the surgeon's learning curve. Demand for the procedure has required rapid training and credentialing of many surgeons with limited experience in endoscopy and the use of instruments that allow only limited viewing of abdominal structures.

Protective effects of dibutyryl cyclic AMP on acute hepatic failure in rats.

To study the effect of cyclic AMP on liver dysfunction, dibutyryl cyclic AMP (DBcAMP, 15 mg/kg) was given to rats with acute hepatic failure induced by D-galactosamine (D-Gal; 500 mg/kg) and lipopolysaccharide (i.e., endotoxin) (Et; 0.5 mg/kg). The survival rate was only 7% for rats given D-Gal and Et (control group), while it was 100% for rats given seven doses of DBcAMP, and 53% for rats given two doses. The ALT level was high at 3475 +/- 488 KU in group III, while it was 242 +/- 69 KU in group I, and 376 +/- 49 KU in group II. The hepaplastin test level was decreased at 24 hr in all groups except group I, in which it was high at 55 +/- 11%. The serum tumor necrosis factor (TNF) level was 155 +/- 42 IU/ml in group I, 463 +/- 30 IU/ml in group II, and 1334 +/- 328 IU/ml in group III. The results of the blood biochemistry and liver tissue blood flow studies were better in the DBcAMP-treated groups, and the serum TNF levels were also lower in the treated groups. Histological examination of the liver showed extensive necrosis in the control group, but mild necrosis and inflammatory cell infiltration in the DBcAMP-treated groups. Therefore, treatment with DBcAMP suppressed acute hepatic failure induced by D-Gal and Et, resulting in a significant increase in the survival rate.

Effect of low-power laser irradiation on impulse conduction in anesthetized rabbits.

Low-power laser analgesic effect was generally accepted in clinical cases, whereas there was no direct evidence to indicate that low-power laser irradiation suppressed an impulse conduction within a peripheral nerve. The effect of low-power laser irradiation on electrically evoked responses within the sural nerve was electrophysiologically analyzed in anesthetized rabbits. High threshold evoked responses (conduction velocity was about 11 m/sec, unmyelinated A delta), which were induced by an electrical stimulation to the peripheral stump of the nerve, were significantly suppressed (9 to 19% inhibition) during low-power laser irradiation, which applied to the exposed sural nerve between the stimulus site and the recording site. The suppressive effect was reversible and recovered to the control level after the irradiation. Experimental evidence indicated that low-power laser irradiation suppressed the impulse conduction of unmyelinated A delta afferents in peripheral sensory nerve, which caused a pain sensation. Our data suggest that low-power laser acts as a reversible direct suppressor of neuronal activity.

Effect of low-power laser irradiation on procollagen synthesis in human fibroblasts.

The conflicting views of the effect of low-power laser (LPL) irradiation on procollagen synthesis have existed at the present time, whereas many clinical studies have tested usefulness of LPL irradiation for the wound healing. To evaluate the effect of LPL irradiation on the procollagen synthesis of human fibroblasts in vitro, LPL irradiation on human fibroblast was carried out using two different culture medium, serum-starved medium and fetal calf serum (FCS)-contained medium. In addition, to investigate the mechanism of the LPL on the procollagen synthesis of human fibroblasts, dexamethasone and methylene blue contained medium were used for inhibition of procollagen product at the pretranslational level and cGMP-mediated processes, respectively. Enhanced effect of LPL was consistently observed in the serum-starved medium (50% increase by a 3 min irradiation), not in the FCS-contained medium. The LPL enhanced effect was not blocked by dexamethasone (3% inhibition) but methylene blue (40% inhibition). Our data suggest that some factors in FCS might interfere with the enhanced effect of LPL on procollagen synthesis and the LPL might act as a direct stimulator of the procollagen synthesis. It seems probable that the LPL enhanced effects might be occurred at the translational level or at the pretranslational level, which is not affected by dexamethasone and cGMP, might be involved in the LPL enhanced effect of the procollagen synthesis in fibroblast.

Vascular thromboxane formation in hemostasis mechanism: correlation between bleeding time and vascular TXB2 in a patient with congenital platelet cyclo-oxygenase deficiency.

We encountered a patient with congenital platelet cyclo-oxygenase deficiency with normal ability to synthesize vascular prostaglandin I2 (PGI2) and thromboxane A2 (TXA2). The patient's peripheral blood monocytes did not show cyclo-oxygenase (COX) activity, but cultured bone marrow fibroblasts showed COX activity. To determine the mechanism of primary hemostasis in this patient, we examined the effect of oral administration of aspirin (1 g) on bleeding time and thromboxane B2 (TXB2), 6-keto prostaglandin F1 alpha (6-keto-PGF1 alpha) production in the blood emerging from the incision in this patient. The bleeding time was markedly prolonged by the administration of aspirin, and this prolongation was associated with the inhibition of TXB2 in the effluent blood, which seemed to be derived from the vessel wall. These findings suggest that vascular TXA2 production plays an important role in the maintenance of hemostasis.

A new technique for laparoscopic cholecystectomy--retrograde laparoscopic cholecystectomy: an analysis of 81 cases.

BACKGROUND AND STUDY AIMS: A new technique of laparoscopic cholecystectomy is presented here. This new method, retrograde laparoscopic cholecystectomy (RLC) from fundus to cystic duct downward, may have advantages when exposure of the cystic duct and the common duct are difficult and therefore hazardous. PATIENTS AND METHODS: We carried out laparoscopic cholecystectomy in 173 patients; RLC was performed in 81, The operative procedure is as follows: first, the cystic duct and artery are exposed at the junction of the ampulla. The cystic duct is clipped, and the artery is divided. Removal of the gallbladder is then started from the fundus to cystic duct downward. After the gallbladder has been dissected from the liver bed, the cystic duct is double-clipped and divided. This approach provides better visualization of the gallbladder, cystic duct, and common duct, with less chance of common duct injury, due to clear identification of the ductal system, without the need for intraoperative cholangiography. RESULTS: Eighty-one RLCs were performed without severe complications, either immediate or late. The mean operating time was 23 minutes shorter in RLC than in the usual laparoscopic cholecystectomy, because intraoperative cholangiography was used much less often. CONCLUSION: RLC appears to be a safe procedure, and does not affect the conventional method.

Colon cancer with a high serum alpha-fetoprotein level.

We report on a patient with colon cancer and a very high serum alpha-fetoprotein level. This 75-yr-old man presented with right lower quadrant abdominal pain. An abdominal CT scan as well as ultrasonography showed a tumor in the cecum. Serum alpha-fetoprotein level was extremely high (3,070 ng/ml). At laparotomy, a large mass was found in the cecum, and a right hemicolectomy was performed. Histological examination, including immunohistochemical study, showed an adenocarcinoma of the colon producing alpha-fetoprotein.

[Influence of splenectomy on drug therapy for acute liver failure induced by D-galactosamine and lipopolysaccharide in rats].

We studied protective effects of dibutyryl cyclic AMP (DBcAMP 15 mg/kg i.p.) and OK-432 (5 KE/body), and the role of the spleen on D-galactosamine (D-Gal 500 mg/kg i.p.) and lipopolysaccharide (endotoxin: Et 0.5 mg/kg i.p.) induced acute liver failure. The survival rates were 10% in the control group (D-Gal+Et), 53% in the group I A (DBcAMP was administered at 1 hour before D-Gal administration), 79% in the group I B (Splenectomy was performed at 24 hours before D-Gal administration on the group I A), 87% in the group II A (OK-432 was administered at 24 hours before D-Gal administration), and 64% in the group II B (Splenectomy was performed at 24 hours before D-Gal administration on the group II A). GOT activities and TNF activities were significantly improved in the treatment groups, and in the group I B and group II A, they were more improved than in the group I A and group II B. In conclusion, spleen had the positive effect for OK-432 treatment, and also had the negative effect for DBcAMP treatment on acute liver failure induced by D-Gal and Et.

The immuno-stimulant OK-432 enhances liver regeneration after 70% hepatectomy.

The effect of reticuloendothelial system activation on hepatic regeneration after 70% hepatectomy was investigated. OK-432, a killed streptococcal preparation which increases reticuloendothelial system function, was administered to rats prior to 70% hepatectomy. Hepatic incorporation of 3H-thymidine 24 h after 70% hepatectomy was enhanced by OK-432 pretreatment. DNA synthesis was greater in pretreated than in control rats and correlated highly with reticuloendothelial system phagocytic activity prior to surgery. Methyl palmitate, which decreases reticuloendothelial system function, was administered to rats prior to 70% hepatectemy. Hepatic incorporation of 3H-thymidine 24 h after 70% hepatoctomy was significantly depressed by methylpalmitate-pretreatment. These data suggest that reticuloendothelial system plays a role in liver regeneration and that hepatocyte proliferation might be enhanced by protection from surgical stress and endotoxins with reticuloendothelial system stimulation by OK-432.

An ultrasonically powered instrument for laparoscopic surgery: a brief technical report of preliminary success.

We report the use of an ultrasonically powered instrument (CUSA) for laparoscopic surgery. A total of 105 patients underwent laparoscopic or laparoscopic assisted surgical procedures. Ninety-one laparoscopic cholecystectomies (LC), 9 laparoscopic appendectomies (LA), 3 laparoscopic colon resections (LCR), and 2 laparoscopic partial gastrectomies (LPG) were done using CUSA. In LC, CUSA separates the areolar connective tissue between gallbladder and liver bed without dividing any sizable vessels or injuring the liver. In LA, LCR, and LPG, CUSA makes mesenteric vessel identification and division rapid and safe. We concluded that CUSA is useful for laparoscopic surgery.

Laparoscopic cholecystectomy from fundus downward.

Laparoscopic cholecystectomy from fundus downward (LCFD) is desirable when exposure of the cystic duct is difficult and hazardous. First the cystic duct and artery are exposed and clipped, and the artery is divided. Then removal of the gallbladder is started from fundus downward. After the gallbladder is dissected from the liver bed, the cystic duct is double clipped and divided. This approach affords better visualization of the cystic duct and common duct with less chance of common duct injury. Twenty-eight LCFDs were performed without complications, immediate or late. LCFD appears to be a safe procedure and does not compromise the retrograde method.

Effects of low-power laser irradiation on multiple unit discharges induced by noxious stimuli in the anesthetized rabbit.

This study discusses the effects of low-power laser irradiation upon multiple unit discharges within a peripheral nerve that were induced by a noxious stimulation in anesthetized rabbits. Responding to a pinch stimulation of plantar skin, transitory increase of neuronal discharges was induced in the sural nerve. This was reduced within a minute, and persistent increases, which continued during a period of the stimulation, occurred. These increases became significantly smaller than the control value during a low-power laser irradiation that was applied to the exposed sural nerve distal to the recording site. These results suggested an inhibitory effect of low-power laser irradiation on the impulse conduction within a peripheral nerve. Possible analgesic effects of low-power irradiation are discussed.