Protective Effect of Hepatocyte Growth Factor Against Degeneration of the Retinal Pigment Epithelium and Photoreceptor in Sodium Iodate–Injected Rats

PURPOSE

To investigate the possible protective effect of hepatocyte growth factor (HGF) against degeneration of photoreceptors and retinal pigment epithelium (RPE) in vivo.

METHODS

Sprague-Dawley (SD) rats received an intravitreal injection of HGF in the right eye. The left eye was injected with vehicle as a control. Two days after the intravitreal injections, rats were administered 40 mg/kg of sodium iodate (NaIO3) intravenously. Scotopic ERGs were elicited by different stimulus intensities with a maximum luminance of 0.84 log cds/m2. To evaluate RPE function, the azide response was evoked by intravenous injection of 0.1 mg sodium azide. These electrophysiological measurements were conducted on days 4, 7, 14, and 28 after the NaIO3 injections. After recording ERGs or azide response, animals were sacrificed for quantification of the histological change and immunohistochemical analysis using antibodies against RPE 65.

RESULTS

The threshold for the scotopic b-wave was significantly lower in HGF-treated eyes than in untreated control eyes (p < 0.005), and maximum b-wave amplitudes (Vbmax) were significantly larger in HGF-treated eyes (p < 0.05) across all experimental time points after NaIO3 injection. Azide response amplitudes were significantly larger in the HGF-treated eyes than in the untreated eyes (p < 0.05). The structure of the outer retina was preserved to a greater degree in the HGF-treated eyes than in the untreated eyes (p < 0.05). Immunohistochemical analysis demonstrated that irregular alignment of the outer nuclear layer was confined to the retinal area that was not stained with RPE 65.

CONCLUSIONS

Our results indicated that an intravitreal injection of HGF provided significant protection against degeneration of the photoreceptor and RPE induced by systemic administration of NaIO3. This suggests that HGF could be used as a therapeutic agent for degeneration of photoreceptors as well as RPE.

Hypoxia accelerates cancer invasion of hepatoma cells by upregulating MMP expression in an HIF-1alpha-independent manner

Tumor hypoxia has been reported to induce tumor progression in several carcinomas. Current studies have shown that hypoxia inducible factor-1alpha (HIF-1alpha) is stabilized under hypoxic conditions and transactivates various genes related to cancer aggressiveness. In the present study, we examined whether hypoxia affects cancer invasion in hepatocellular carcinoma. We aimed to solve the molecular mechanism of tumor invasion under the hypoxic condition. We showed that tumor hypoxia accelerated cancer invasion in two hepatoma cell lines. Using Western blot and RT-PCR analyses we demonstrated striking evidence that the expression of HIF-1alpha, ETS-1, MMP-7 and MT1-MMP was strongly upregulated by hypoxic stimulation. To examine whether these invasion-related genes are regulated by HIF-1alpha, we treated hepatoma cells with TX-402, which was reported to repress HIF-1alpha expression. HIF-1alpha expression was strongly repressed by the TX-402 treatment. In contrast, the expression of ETS-1, MMP-7 and MT1-MMP mRNA was not affected by TX-402 treatment. We further established stable transfectants in which HIF-1alpha dominant negative vector was introduced into Hep3B cells (pHIF-1alphaDN). In the pHIF-1alphaDN cells, the expression of ETS-1, MMP-7 and MT1-MMP was not repressed. Moreover, the invasion activity of pHIF-1alphaDN was not altered, compared with that of the mock. In hepatoma cells, we provided evidence that hypoxic stress accelerates cancer invasion by upregulating ETS-1 and the MMP family by an HIF-1alpha-independent pathway.

Exotic radiation from a photonic crystal excited by an ultrarelativistic electron beam

We report the observation of an exotic radiation (unconventional Smith-Purcell radiation) from a one-dimensional photonic crystal. The physical origin of the exotic radiation is direct excitation of the photonic bands by an ultrarelativistic electron beam. The spectrum of the exotic radiation follows photonic bands of a certain parity, in striking contrast to the conventional Smith-Purcell radiation, which shows solely a linear dispersion. Key ingredients for the observation are the facts that the electron beam is in an ultrarelativistic region and that the photonic crystal is finite. The origin of the radiation was identified by comparison of experimental and theoretical results.

Third-order neuronal responses contribute to shaping the negative electroretinogram in sodium iodate-treated rats

PURPOSE

To determine possible mechanisms that shape the negative electroretinograms (ERGs) in rats with photoreceptor degeneration induced by destruction of the retinal pigment epithelium.

METHODS

Sprague-Dawley rats (n = 48) were injected intravenously with 60 mg/kg of sodium iodate (NaIO(3)). Full-field ERGs were elicited by different stimulus intensities with a maximum luminance of 1.23 log cd-s/m(2) and recorded at 6 hr and on days 7, 14, and 28 after the NaIO(3) injections. DL-2-amino-4-phosphonobutyric acid (APB, 1 mM) or N-methyl-L-aspartic acid (NMDA, 5 mM) was injected into the vitreous cavity to isolate photoreceptor (PIII), second-order, and third-order neuronal responses. After recording the ERGs, animals were sacrificed for histological analysis.

RESULTS

Negative ERGs were recorded under scotopic conditions on day 7 after the NaIO(3) injection. An intravitreal injection of NMDA eliminated most of the a-wave, resulting in the abolition of the negative ERG. On days 14 and 28, the a-wave amplitudes were reduced compared to those on day 7 with the loss of the negative ERGs. The mean amplitudes of the PIII and second-order neuronal responses were progressively reduced until day 7. In contrast, the mean amplitude of the third-order neuronal responses were relatively well-preserved until day 7 and then were decreased between days 7 and 14. As a result, the amplitude of the third-order neuronal response dominated over the second-order neuronal response on day 7. There was no significant difference in the middle and inner retinal morphology at each time point.

CONCLUSIONS

NaIO(3) produced negative ERGs transiently, and the third-order neuronal responses were the main contributors to the negative ERG. The relative preservation of the third-order neuronal response plays a role in shaping the negative ERGs in this model.

Neuroprotective Effect of Hepatocyte Growth Factor against Photoreceptor Degeneration in Rats

PURPOSE

To determine whether hepatocyte growth factor (HGF) has a neuroprotective effect against photoreceptor degeneration in rats.

METHODS

Eight-week-old Sprague-Dawley (SD) and 24-day-old Royal College of Surgeons (RCS) rats received an intravitreal injection of HGF in the right eyes. The left eyes were injected with vehicle and served as the control. Two days after the injections, the SD rats were exposed to fluorescent light of 3000 lux for 72 hours. Scotopic and photopic electroretinograms (ERGs) were recorded 2 weeks after the light damage and at 70 days of age in RCS rats. After the ERG recordings, the animals were killed for histologic analysis. Some RCS rats were killed at 2 weeks after HGF-treatment for TdT-dUTP terminal nick-end labeling (TUNEL) studies.

RESULTS

In both light-damaged and RCS rats, the thresholds for the scotopic and photopic b-wave were significantly lower in the HGF-treated eyes than in the control eyes (P <0.02). The maximum b-wave amplitudes (Vbmax) of the scotopic and photopic ERGs were significantly larger in the HGF-treated eyes (P <0.0005) with a significantly greater number of photoreceptor nuclei than in the control eyes in both animal models (P <0.005). The vehicle-injected eyes of RCS rats had significantly larger numbers of TUNEL-positive photoreceptor nuclei than the HGF-treated eyes (P=0.005).

CONCLUSIONS

Intravitreal HGF led to the morphologic and physiological preservation of photoreceptors in rats with photoreceptor degeneration induced by phototoxicity or a gene mutation. The antiapoptotic effect may be the mechanism for the neuroprotective action of HGF.

Observation of millimeter-wave radiation generated by the interaction between an electron beam and a photonic crystal

We observed directional light emission in the millimeter-wave region when a high-energy (150 MeV) electron beam passes just above a photonic crystal made of polytetrafluoroethylene beads ( approximately 3.2 mm in diameter). The relation between the momentum and the energy of the emitted photons strongly suggests that the observed light is generated by the umklapp scattering process that changes the evanescent waves emitted by the electron beam into observable ones. By comparing the observed spectra with calculated ones based on the photonic band structure, we found that generated photons excite the photonic band modes making them observable as enhanced fine structures in the emission spectra.

Helicobacter pylori infection induces duodenitis and superficial duodenal ulcer in Mongolian gerbils

BACKGROUND

There is no direct evidence for an animal model of Helicobacter pylori induced duodenal ulcer.

AIM

In this study we evaluated the roles of bacterial strain and age of experimental animals in induction of duodenitis and duodenal ulcer in Mongolian gerbils after H pylori infection.

METHODS

Specific pathogen free Mongolian gerbils were inoculated orally with three bacterial strains (H pylori ATCC 43504, TN2GF4, and K-6, a clinical isolate from a patient with gastric cancer in our clinic). These strains have both the cagA gene and VacA. Five week old gerbils were used to emulate prematurity infection and 14 week old animals were used as mature test subjects. Animals were observed for 12 weeks after inoculation. Interleukin 8 (IL-8) production in gastric epithelial cells (MKN74) after coculture with the H pylori strains was measured by ELISA.

RESULTS

Gastritis and gastric ulcers were found in all gerbils infected with the three strains. However, duodenitis and gastric metaplasia were seen more frequently in gerbils infected with TN2GF4 and K-6 strains than in the ATCC 43504 infected or control groups (p<0.05). Superficial duodenal ulcers with severe duodenitis and gastric metaplasia were found in two gerbils inoculated at 14 weeks with the TN2GF4 strain but none at five weeks. The TN2GF4 strain stimulated significantly higher levels of IL-8 than ATCC 43504 and K6 strains (p=0.0039).

CONCLUSIONS

When injected into adult Mongolian gerbils, a specific strain (TN2GF4) of H pylori can induce duodenitis with gastric metaplasia and superficial duodenal ulcers. Induction of duodenal ulcer in an animal model fulfills the requirements of Koch's postulates for establishing a role for H pylori as a causative agent.

Clarithromycin resistance, but not CYP2C-19 polymorphism, has a major impact on treatment success in 7-day treatment regimen for cure of H. pylori infection: a multiple logistic regression analysis

Mutations in the gene encoding the CYP2C-19 enzyme for PPI metabolism have been shown to enhance the chance for a cure in a H. pylori-positive patients using a two-week dual-therapy regimen involving omeprazole and amoxicillin. However, the impact of CYP2C-19 genetic polymorphism on eradication rates of a one-week triple-therapy regimen has not been examined. In this cohort study, 156 H. pylori-positive peptic ulcer or NUD patients who presented to our university hospital were recruited. They were treated by one-week omeprazole-amoxicillin-clarithromycin therapy. Host and bacterial predictive factors including H. pylori susceptibility and CYP2C-19 genotyping, as well as cure rate for H. pylori infection, were studied. Cure rate was 85.9% (95% CI: 79-91%) on an intent to treat (ITT) basis. By multiple logistic regression analysis, only clarithromycin resistance had a significant impact on treatment success (odds ratio 28.7: 95% CI: 6-172). CYP2C-19 genetic polymorphism was not associated with a significant change in cure rate. These observations indicate only clarithromycin susceptibility, not CYP2C-19 polymorphism, has a major impact on the treatment success when using a seven-day OAC H. pylori treatment regimen.

Comparison of the efficacy of 400mg and 800mg of clarithromycin used with lansoprazole and amoxicillin in eradication regimens for Helicobacter pylori infection in a Japanese population

We conducted a randomized prospective comparative study to determine whether a 1-week lansoprazole-amoxicillin-clarithromycin (LAC) regimen with 800 mg of clarithromycin a day was more effective such a regimen with 400 mg daily in the Japanese population. One hundred and seventy-five Helicobacter pylori-positive patients were randomly assigned to receive one of two different 7-day regimens, one with clarithromycin 400 mg (LAC 400 regimen) and the other with clarithromycin 800 mg (LAC 800 regimen). The cure rates for both regimens were similar, although adverse effects were significantly more frequent in the LAC 800 regimen, suggesting that 400 mg of clarithromycin may be sufficient in our patient population.

On-site diagnosis of H. pylori infection by urine

We have recently developed an on-site diagnostic kit for H. pylori infection using urine (utilizing immunochromatographic method employing a nitrocellulose membrane coated by extracted H. pylori antigen). Accordingly, we investigated its usefulness in 155 consecutive dyspeptic patients using the 13C urea breath test as a gold standard and further compared its performance with two commercially available rapid diagnostic kits that use whole blood (Helisal Rapid Blood, and ImmunoCard H. pylori). As the results, the urine based on-site diagnostic kit provided 95.9% sensitivity and 87.9% specificity with 92.9% accuracy, which were comparable or even better than that of both rapid whole blood tests, suggesting its usefulness in screening of H. pylori infection.

Insufficient diagnostic accuracy of imported serological kits for Helicobacter pylori infection in Japanese population

Although there are many reports of the high diagnostic accuracy of commercially available serologic kits for Helicobacter pylori infection in Western countries, they rarely has been investigated in oriental population. Accordingly we examined their usefulness in 492 Japanese patients with dyspeptic symptoms. Diagnostic accuracy of 4 imported serologic kits (HEL-p TEST, HM CAP, G.A.P IgG, Helico G2) was investigated using the (13)C-urea breath test as the gold standard. When intermediate results were excluded, the sensitivity, specificity and accuracy of these serologic tests ranged from 88.6% to 97.8%, 67.9% to 85.9%, and 87.9% to 91.4%, respectively, which were comparable with reported median accuracy in the Western population. However, there were many intermediate results in these tests, ranging from 5.3% to 23.0%. Their usefulness seemed to be limited in our patient population because of the large number of intermediate results.

Low-threshold laser oscillation due to group-velocity anomaly peculiar to two- and three-dimensional photonic crystals

An analytical expression of the lasing threshold for arbi trary photonic crystals was derived, which showed their reduction due to small group velocities of electromagnetic eigenmodes. The lasing threshold was also evaluated numerically for a two-dimensional photonic crystal by examining the divergence of its transmission and reflection coeffcients numerically. A large reduction of lasing threshold caused by a group-velocity anomaly that is peculiar to two- and three- dimensional photonic crystals was found.

Role of extracellular matrix on colonic cancer cell migration and proliferation

A simplified method to quantitatively analyze the migration and proliferation capacity of a colonic cancer cell line (SW837) in vitro was developed. The objective of this study was to evaluate the role of the extracellular matrix in colon cancer metastasis. We used this model to investigate the effects of the extracellular matrix components collagen type I and type IV, laminin, and fibronectin on the migration and the proliferation of cancer cells. Migration was fastest on laminin and slowest on collagen type I. Further, proliferation was highest on laminin of all extracellular matrices groups studied. Therefore, it is concluded that laminin had pronounced effects on migration and proliferation of SW837 cells. These findings suggest that the composition of the extracellular matrix plays an important role in the mechanism of metastasis of colon cancer cells.

A direct involvement of the central nervous system in hypophagia and inhibition of respiratory rate in rats after treatment with O,O,S-trimethyl phosphorothioate

O,O,S-Trimethyl phosphorothioate (OOS-TMP) is known to induce unique symptoms, which are characterized by hypophagia, progressive weight loss, and hypothermia. To determine whether there is the possibility of a causal relationship between these toxic symptoms and a direct action of OOS-TMP on the central nervous system, we investigated the development of these symptoms in Fischer 344 female rats after oral or intracerebral treatment with OOS-TMP. Oral administration of OOS-TMP at 20 mg/kg induced marked hypophagia, progressive weight loss and hypothermia. Moreover, inhibition of respiratory rate was observed immediately after treatment. It lasts during the entire experimental period. Profound hypothermia below 34 degrees C was observed more frequently in the rats, which became hypercapnic (PaCO2 > or = 50 mmHg). In contrast, administration of OOS-TMP at 20 mg/kg (as much as the oral dose) into the cerebral lateral ventricle succeeded in inducing hypophagia, progressive weight loss and lowered respiratory rates. On the other hand, by this route of administration, OOS-TMP at 20 mg/kg failed to induce hypothermia, hypercapnia and lung injury. The present results suggest that hypophagia and inhibitions of respiratory rate are attributable to the direct action of OOS-TMP on the central nervous system, while other symptoms are associated with lung injury.

O,O,S-trimethyl phosphorothioate increases Ca2+ independent nitric oxide synthase activity in the lung but decreases Ca2+/calmodulin dependent type in the cerebellum in Fischer 344 rats

In the present study, we investigated the possible role of nitric oxide synthase in lung injury using female Fischer 344 rats as a model animal and O,O,S-trimethyl phosphorothioate as an example of lung toxicants. One form of nitric oxide synthase, Ca2+/calmodulin dependent type, decreased monotonously in a dose-dependent manner in the cerebellum. In contrast, O,O,S-trimethyl phosphorothioate increased activities of Ca2+ independent nitric oxide synthase in the lung in a dose-associated manner from 5 mg/kg to 15 mg/kg, but decreased at 30 mg/kg. Lung toxicity of O,O,S-trimethyl phosphorothioate, however, as judged both by functional impairments (PaCO2 and [HCO3-]) and histopathological changes, increased sharply at 30 mg/kg. We thus tested the hypothesis that a potent nitric oxide synthase inhibitor, NG-nitro-L-arginine-methyl ester, may modify lung injury induced by O,O,S-trimethyl phosphorothioate. Treatment with NG-nitro-L-arginine-methyl ester at 20 mg/kg/day aggravated lung injury induced by O,O,S-trimethyl phosphorothioate: Pulmonary oedema and bleeding occurred, leading to an increase in mortalities at 15 mg/kg of O,O,S-trimethyl phosphorothioate, at which level it did not induce such changes as when dosed alone. These findings indicate that nitric oxide synthase in the lung might play a protective role in lung injury.

Enhanced levels of lipid peroxidation and xanthine oxidase activity in the lung of male Sprague-Dawley rats following treatment with O,O,S-trimethyl phosphorothioate

The purpose of this study was to investigate the roles of lipid peroxidation and a prototypical radical generating enzyme, xanthine oxidase, in lung injury caused by O,O,S-trimethyl phosphorothioate (OOS-TMP). Animals (five per group) were dosed with OOS-TMP at 40 mg/kg and sacrificed on the 1st, 3rd or 7th day after treatment. OOS-TMP increased lipid peroxidation (Mean +/- S.E.) to 139 +/- 9.6% of the control values in the lung and to 623 +/- 203% in the liver on the 1st day. When rats were dosed with OOS-TMP at 20, 40 and 60 mg/kg, lipid peroxidation in the lung and the liver were increased in a dose-dependent manner. In the lung, the total activity of xanthine oxidase was coincidentally increased. In contrast, the activities of superoxide dismutase and catalase were not affected. Effects of OOS-TMP on lipid peroxidation and the total activity of xanthine oxidase were completely abolished by coadministration with O,O,O-trimethyl phosphorothionate of a non-toxic dose (1 mg/kg), which antagonizes the lung injury after treatment with OOS-TMP. The present results indicate that free radical formation may be involved in lung injury after OOS-TMP treatment through activation of radical producing enzymes such as xanthine oxidase.

[Pharmacokinetics of isosorbide dinitrate studied by the extrapolation model]

To make a pharmacokinetic model of isosorbide dinitrate (ISDN), we infused ISDN at 1, 10 or 30 micrograms.kg-1.min-1 into anesthetized rabbits and measured concentrations of ISDN and its metabolites (2-ISMN and 5-ISMN) in plasma, urine and bile. We found the concentration gradient of ISDN between arteries and veins and between the ascending aorta and femoral artery. These concentration gradients may occur due to metabolism and accumulation of ISDN in many organs and tissues, let alone the vascular endothelium. There was no significant difference in plasma concentrations of ISDN or its metabolites between the hepatic vein and femoral vein. It seems that ISDN is metabolized in various organs and tissues. By ISDN infusion of more than 10 micrograms.kg-1.min-1, the plasma concentration of ISDN showed a pronounced increase. It appears that there is metabolic saturation of ISDN. Using these informations, we extrapolated the model to human and the estimated values were compared with observed values to determine the validity of the extrapolation model. There was no remarkable differences between the estimated values and observed values. This suggests the validity of the model. The plasma concentrations of ISDN, estimated by this extrapolated model, showed a linear increase (Y = 30X) with the flow rate range of 0.2-5.0 micrograms.kg-1.min-1, when the metabolic rate was normal. With ISDN infusion of more than 5.0 micrograms.kg-1.min-1, the plasma concentrations of ISDN showed a pronounced increase. In the conditions of impaired metabolism, the plasma concentrations of ISDN increase exponentially.(ABSTRACT TRUNCATED AT 250 WORDS)

[Patients with calcinosis cutis in National Leprosarium Matsuoka Hoyo-En]

As of the year 1991 there were 358 leprosy patients in National Leprosarium Matsuoka Hoyo-En, including 223 patients (62.3%) who had received the injections of chaulmoogra oil before. Calcinosis cutis caused probably from the injections was noted on 73 patients (32.7%): 67 lepromatous and 6 tuberculosis cases. It has never been reported before that the T type patient suffering from calcinosis cutis was observed in the cases of the chaulmoogra oil injection in Japan. The detectable positions of calcinosis cutis were mostly at the injected sites, that is, outside the right brachium followed by bilateral-branchia and crura. In the group of patients with calcinosis cutis, the anti-PGL antibody was negative for the most part. Urinalyses, peripheral blood figure analyses, histopathological tissue examinations of calcium deposition, X-ray diffraction patterns, differential thermal and gravitational analyses, and chemical analyses were performed on all patients with this disease. Further, as the result of this study six patients with calcinosis cutis caused by sulpyrine was also found. The major component of the deposit by the drug was calcium phosphate. These calcinosis cutis were considered to be of trophopathic calcinosis based on the disorder of subcutaneous tissue due to the injections of respective drugs: chaulmoogra oil and sulpyrine.

[Continuous intravenous pethidine infusion for analgesia after upper abdominal surgery: a randomized, prospective double-blind comparison with continuous epidural infusion of pethidine]

We conducted a randomized double-blind controlled study comparing patients receiving continuous intravenous pethidine infusion with those receiving continuous epidural infusion for postoperative analgesia after upper abdominal surgery. Twenty patients scheduled for upper abdominal surgery were randomized into 2 groups: IV Group (n = 10) received 100 mg.24 h-1 of pethidine intravenously and saline epidurally, Epi Group (n = 10) received 100 mg.24 h-1 of pethidine epidurally and saline intravenously. During 24-hour postoperatively, verbal descriptor pain scale, sedative scale, respiratory rate, pulse rate and blood pressure were evaluated at each 2 hours. During 72-hour postoperatively, visual analogue pain scale (added at 6-hour postoperatively), supplemental doses of pethidine, and side effects were evaluated at each period of 12 hours. There was no significant difference in the rating of analgesia in either group during 72-hour postoperatively. However in the first 12 hours postoperatively, VAS in Epi Group tended to be lower than that in IV Group. There was no respiratory depression in either group. We conclude that continuous intravenous infusion of 100 mg.24h-1 of pethidine was effective for postoperative analgesia after upper abdominal surgery without major side effects, and almost the same analgesic effect was obtained as compared with continuous epidural analgesia.

Effect of controlled mechanical ventilation without positive end-expiratory pressure on right ventricular function after coronary artery bypass graft surgery

To evaluate the changes in right ventricular function during controlled mechanical ventilation (CMV) without positive end-expiratory pressure (PEEP) and during spontaneous breathing, we compared right ventricular ejection fraction (RVEF), right ventricular end-diastolic volume index (RVEDVI), and right ventricular end-systolic volume index (RVEDVI) using a thermodilution technique after coronary artery bypass graft surgery. Patients were divided into two groups on the basis of changes in RVEDVI from CMV to spontaneous breathing: group U (n = 6) consisted of patients whose RVEDVI increased during spontaneous breathing compared with mechanical ventilation, group D (n = 3) consisted of patients whose RVEDVI decreased during spontaneous breathing compared with mechanical ventilation. PVRI values during CMV in group D were significantly larger than those in group U. Patients in group U showed no increase in RVEDVI, or decrease in RVEF during CMV without PEEP. However, the remaining 3 patients in group D showed an increase in RVEDVI and a decrease in RVEF during CMV. Mean PAP, RAP, RV systolic pressure, RV end-diastolic pressure, PWP, HR, and mean arterial pressure in both groups were comparable, and showed no significant difference at each of the measured points by 24 hrs postoperatively. Then, RVEF, RVEDVI and RVESVI measured by thermodilution technique is useful in evaluating ventricular function at bedside in ICU.

[Effect of continuous infusion of diltiazem on cardiovascular responses to laryngoscopy and intubation]

We studied the cardiovascular responses to laryngoscopy and intubation in 30 patients who received continuous infusion of either diltiazem 10 micrograms.kg-1.min-1, 40 micrograms.kg-1.min-1 or saline as control group during 20 min before induction. Heart rate, arterial pressure, rate pressure product (RPP), pressure rate quotient (PRQ) were measured starting 20 min before induction to 3 min after tracheal intubation. The increases in arterial pressure and RPP following tracheal intubation were reduced significantly in patients receiving diltiazem 40 micrograms.kg-1.min-1, but they were not reduced in patients receiving diltiazem 10 micrograms.kg-1.min-1 compared with control. We conclude that continuous infusion of diltiazem during 20 min before induction is effective for preventing the increases in arterial pressure and RPP following tracheal intubation, and the optimal infusion rate is from 10 to 40 micrograms.kg-1.min-1.

[Continuous intravenous infusion of pethidine or buprenorphine for postoperative analgesia]

Efficacy of continuous intravenous infusion for postoperative analgesia was evaluated in 20 patients who had undergone abdominal surgery for 72 hours postoperatively. The patients were randomly allocated to two groups: one group received continuous intravenous infusion of buprenorphine at 0.2 mg.24 hr-1 using a non-electronic, portable infusor 0.5 ml.hr-1 type (Baxter), while the other received infusion of pethidine at 50 mg.hr-1. During the first 12 postoperative hours, the frequency of "Fair" rating which indicated need of supplemental analgetics was significantly higher than the later 12-hour period until 72 hours in both groups. However, although during the first 12 hours continuous intravenous infusion was inadequate to alleviate postoperative pain compared with other 12-hour period, no patient received supplemental analgesics more than 2 times. During the 24 to 72 postoperative hours, 70% of cases needed no supplemental analgesics to alleviate postoperative pain. Continuous intravenous infusion of 0.2 mg.hr-1 buprenorphine or 50 mg.hr-1 pethidine was inadequate for postoperative analgesia during immediately after the operation to 36 hours postoperatively, especially during the first 12-hour period. However, this infusion was effective during 36 to 72 postoperative hours. There was no significant difference between buprenorphine group and pethidine group.

[The evaluation of incremental positive end-expiratory pressure on right ventricular hemodynamics as determined by the thermodilution technique]

Effects of incremental positive end-expiratory pressure (PEEP) on right ventricular (RV) hemodynamics were studied in 10 patients undergoing coronary artery bypass grafting, abdominal aneurysmectomy and partial hepatectomy, using Swan-Ganz catheter mounted with the rapid response thermistor. PEEP was increased from 0 (baseline) to 15 cmH2O with increment of 5 cmH2O, and right ventricular ejection fraction (RVEF), RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), and cardiac output (CO) were computed with a thermodilution technique at each PEEP. At 15 cmH2O PEEP, RVEF, RVEDVI and RVESVI were comparable with the baseline, while right arterial pressure, RV peak systolic pressure and mean pulmonary arterial pressure increased significantly compared with the baseline. Increased afterload of RN caused by PEEP did not affect RV contractility. Decreased cardiac and stroke volume indices were attributed to the decrease of preload caused by the increase of intrathoracic pressure. We conclude that PEEP at 5 to 15 cmH2O does not influence right ventricular hemodynamics, and RVEDV is a reliable index to monitor RV hemodynamics instead of right arterial pressure to determine optimal PEEP.

[The effect of continuous epidural infusion of a combination of 1% mepivacaine and buprenorphine for post-operative pain relief]

Using a portable 2 ml.hr-1 type infusor (Baxter Infusor), the effect of continuous epidural infusion for post-operative pain relief for 72 hours was studied in 32 patients after upper abdominal surgery. The patients were randomly allocated into four groups: Group 1 (n = 8) received continuous epidural infusion of 1% mepivacaine and buprenorphine 0.2 mg (48 ml.hr-1); group 2 (n = 8) 1% mepivacaine and buprenorphine 0.4 mg (48 ml.hr-1); Group 3 (n = 8) saline and buprenorphine 0.2 mg (48 ml.hr-1); Group 4 (n = 8) saline and buprenorphine 0.4 mg (48 ml.hr-1). The effect was evaluated at intervals of 12-hour until 72 hours postoperatively. Patients received supplemental buprenorphine intramuscularly as needed. In each period during the 12 to 72-hour after operation, the percentage of the patients who needed no supplemental buprenorphine was 62.5-100%, which is higher than during the 0 to 12-hour (25.0%). The percentage of the patients who showed no pain on coughing and changing in position in Group 1 and 2 was higher than in Group 3 and 4 in each period (P less than 0.05 12-24 and 36-72 hr). Continuous epidural infusion using Baxter Infusor with the combination of 1% mepivacaine and buprenorphine is effective for alleviating postoperative pain during the 12 to 72 hours after the operation, and for prevention of pulmonary complications.

[Ventricular arrhythmia associated with the use of an electrosurgical unit in a patient with a Swan-Ganz catheter]

We experienced short-run type ventricular arrhythmia associated with use of electrosurgical unit (ESU) in a patient with a Swan-Ganz catheter. Leakage current was not detected from the body of the five different devices used in this study. Nevertheless, there is a possibility of leakage current to the electrode of the intra-cardiac catheter thereby exciting the myocardium, because the grounding of the five devices used simultaneously on the patient were not of EPR system. The other possibility, that is the occurrence of pulse direct current voltage by rectification of high frequency current at the contact point of electrosurgical knife's tip and vital organ is a speculation but not underlined by a definite proof. In summary, the cause of ventricular arrhythmia associated with the use of ESU could not be identified in the present case. It must always be remembered that whatever safety measures may be prescribed for electrical instruments, a complete prevention of EMI is impossible. Also it must be stressed that whenever many devices are used simultaneously on a patient, EPR system is very important for avoiding electrical hazard.

[Evaluation of the efficacy of continuous epidural block with low concentration of local anesthetics in patients with ureterolithiasis]

Forty patients with ureterolithiasis were studied to evaluate the efficacy of a continuous epidural block with local anesthetics. The patients were randomly allocated into 3 groups: first group (n = 7) received continuous epidural administration of 1% mepivacaine at a rate of 2 ml.hr-1; second group (n = 19) received intermittent bolus administration of the same anesthetic 4-5 times daily; and third group (control group, n = 14) was treated by conventional therapy including infusion of Ringer's solution and diuretics. Among 3 groups, a comparison of the rate of abortion of ureter stone, the rate of mobilization of stone, and the frequency of operation was performed. The rate of abortion in group 1 was significantly higher than those of group 2 and control. The rate of mobilization of stone in group 1 tended to be higher than group 2 and control. Also the frequency of operation in group 1 tended to be lower than group 2. Effect of continuous administration with 1% mepivacaine in patient with ureterolithiasis was comparable to that of intermittent bolus administration of 2% mepivacaine or 0.5% bupivacaine reported. We conclude that the continuous block with 1% mepivacaine is effective and safe for treating the patient with ureterolithiasis.

[A case of delirium which occurred during otorhinolaryngological treatment under local anesthesia--the importance of close communication between practitioners and local general hospitals]

We experienced a case of delirium which occurred during treatment of chronic sinusitis under local anesthesia in a ENT practitioner, which took an unique course. We were able to treat the patient immediately after occurrence of the complication because we have emergency hot-line between anesthesiologists in our hospital and the practitioners in our area. Fortunately the patient recovered without severe sequelae due to immediate therapy. We consider that in emergency cases, a close communication between practitioners and local general hospitals is important for exact diagnosis and suitable treatments as well as for life-saving procedures.

Nd:YAG laser therapy for infertility with a contact-type probe

Laparoscopic Nd:YAG laser surgery for tubal adhesiolysis, hydrosalpinx and other disorders is an effective treatment for female infertility that causes relatively little tissue damage. In initial studies using contact-type probes, the 0.4-mm-diameter probe and 10 mm/sec incision speed were found to cause less tissue degeneration than did other combinations (P less than .05). Fifteen infertile women were treated at laparoscopy with a Nd:YAG laser; one of six with hydrosalpinx achieved pregnancy after salpingostomy using a contact-type probe, two of three with tubal adhesions achieved pregnancy after adhesiolysis with the Nd:YAG laser, and three of six with polycystic ovaries achieved pregnancy after wedge resection using a contact-type probe. Five of fifteen infertile women conceived after Nd:YAG laser surgery with a contact-type probe under laparoscopy. We confirmed that contact irradiation with a ceramic incising probe is capable of creating an adequate incision at low power levels and that laparoscopic Nd:YAG laser surgery for infertile women is an effective treatment.

Obsessive-compulsive symptoms in childhood and adolescence

We investigated 61 patients (38 boys and 23 girls) under 18 years of age with obsessive-compulsive symptoms seen in the Department of Psychiatry, Nagoya University Hospital, from 1982 until 1986. In this period, a total of 1293 patients under 18 years of age visited the clinic. The percentage of patients with obsessive-compulsive symptoms was 5%. The earliest onset of symptoms was at age 3 years, and the average age of onset was 11.6 years. We found no particular tendency in terms of the number of siblings and the birth order of the patients. Obsessive traits were the fundamental personality traits of patients. Moreover, according to the other characteristics of personality, the patients were subdivided into schizothymic, viscous temperament, and cyclothymic. Parents of the patients were more apt than usual to have obsessive-compulsive personalities. Psychiatric disturbances and occupations were also investigated. Incidents related to school situations commonly triggered obsessive-compulsive symptoms. The most frequently noted obsessive thought was dirt phobia, and the most common compulsive behavior was washing. School refusal and violence at home were especially common as associated symptoms of obsessive-compulsive symptoms. We also describe the treatment regimen and the outcomes of the patients.

X-ray determination of static displacements of atoms in alloyed Ni3Al

Single crystals of Ni3(Al, M) were grown by the Bridgman method, where M is Ti, V, Cr, Mn, Fe, Nb, Mo and Ta. The composition was controlled to be about Ni75Al20 M 5 so that the alloying element, M, substitutes mainly for Al. With these crystals conventional X-ray structural analysis was performed. The measured static displacements of atoms from the average lattice points depended largely on the alloying elements and varied in the range 0.00–0.13 Å for Ni atoms and 0.09–0.18 Å for Al atoms. It was found that these atomic displacements correlated well with the atomic radius of the alloying element, M. For example, when the atomic radius of M is larger than that of Al, the static displacements are large for the atoms in the Al sublattice but small for the atoms in the Ni sublattice. By contrast, when the atomic radius of M is smaller than that of Al, the displacements are more enhanced in the Ni sublattice than in the Al sublattice. Thus, there is an interesting correlation between the atomic displacements in both the Al and Ni sublattices in the presence of alloying elements. This seems to be one of the characteristics of alloyed compounds with several sublattices.