Age estimation based on three-dimensional measurement of mandibular central incisors in Japanese.

The purpose of this study was to investigate an age estimation method that considers gender as well as three-dimensional measurement of the components, specifically enamel and dentin. A total of 155 mandibular central incisors aged 12-79 years old which was chosen from the collection stored at the Department of Anatomy in Tokyo Dental College and had no opened apex, caries or restorative treatment, were examined. Samples were scanned using micro-CT HMX225 ACTIS4. Based on the sliced image data, three-dimensional structures were obtained and the volumes of enamel, dentin, and pulp cavity were measured. Regression equations for age estimation were then determined. The accuracy of age estimation equations for each region, volume ratio, and sex was assessed using the determination coefficient R(2) as well as the standard errors of estimated values. The root region alone had a comparable accuracy to that of the whole tooth and the crown region had a relatively lower accuracy. In the whole tooth and the crown region, slightly higher correlations were observed for pulp/tooth volume ratios in which enamel was excluded. Females tended to have higher accuracy compared to males. The estimated age was higher in males compared to females for the same volume ratio of the pulp cavity. The highest correlation in both genders with age was observed for the volume ratio of the pulp cavity to the whole tooth excluding the enamel (males, R(2)=0.67; females, R(2)=0.76). The 95% confidence intervals for the population regression showed different distributions for each sex. In the 95% prediction intervals for age estimation, females tended to have narrower intervals and higher accuracy compared to males. Therefore, the use of gender-specific equations is recommended for age estimation.

Influence of the support base on the sorption of Co(II) with mixed solvents.

Theonyltrifluoroacetone (TTA) mixed with trioctyl phosphine oxide (TOPO) have been supported on Amberlite XAD-4, silica gel and wood powder. The resulting resins have been used to study the sorption of cobalt(II) from acetate buffer and their sorption capacities were determined and were found to be 12.38, 11.61 and 6.51 mg g(-1) for TTA+TOPO/Amberlite XAD4, TTA+TOPO/silica gel and TTA+TOPO/wood, respectively. The experimental results showed that the sorption of Co(II) increases with its initial concentration. The results can be fitted by Freundlich isotherm in the studied cobalt concentration range [10(-4)-10(-3) M] and 1/n values are 1.07, 1.17 and 1.73 for Amberlite XAD4, silica gel and wood powder, respectively. The sorption of Co(II) onto the prepared resins was found to follow the pseudo-second order model and the sorption rate have the values 8.79x10(-3), 10x10(-3) and 16x10(-3) g mg(-1)min(-1) for Amberlite XAD4, silica gel and wood powder, respectively. Thermodynamic parameters have also been calculated for the three systems and sorption process was found to be spontaneous and endothermic one.

The role of some compounds on extraction of chromium(VI) by amine extractants.

The extraction of hexavalent chromium, Cr(VI), from hydrochloric acid aqueous solution using Aliquat 336 and Alamine 336 extractants was performed under different experimental conditions. The data clarify that one molecule of amine extractants shares with approximately one molecule of HCl to extract two molecules of Cr(VI) from 1M HCl aqueous solutions. The extraction is an exothermic process and possesses enthalpy change values of -41.02 and -28.08 kJ mol(-1) for the extraction by Aliquat 336 and Alamine 336, respectively. The presence of potassium chloride greatly increases the extraction of Cr(VI) by amine extractants while the addition of some phenolic compounds such as phenol, dichlorophenol, o-nitrophenol and beta-naphthol decreases this extraction under the same experimental conditions.

Change in hepatic arterial hemodynamics induced by hepatocellular carcinoma detected with Doppler sonography.

PURPOSE: To understand the hemodynamic differences between the hepatic arterial branches that supply hepatocellular carcinomas (HCCs) and those that do not, we compared the velocity waveforms of both types of arteries. METHODS: Using duplex color Doppler sonography, we examined 38 patients with HCC localized within a single lobe of the liver and 34 patients with chronic liver disease but without HCC (controls). We measured angle-corrected peak systolic velocity and the pulsatility index (PI) of color-coded hepatic arteries along the right anterior segmental portal branch and the vertical segment of the left portal vein. RESULTS: There was no significant difference in peak systolic velocity and PI between the arterial branches tested in the controls. In contrast, we found a significantly lower PI and a higher peak systolic velocity in the arterial branches supplying the tumor than in those not supplying the tumor in patients with an HCC 3 cm or larger in diameter (p < 0.05). The degree of these hemodynamic changes correlated with the tumor size and the presence or absence of tumor thrombus in the major portal branches. CONCLUSIONS: These results indicate that the hepatic arterial branch supplying an HCC has a lower impedance than the branch not supplying the tumor.

Phase shift of the hepatic vein flow velocity waveform in chronic liver disease: experimental and clinical studies.

We examined animal models and studied patients with chronic liver disease to evaluate phase shift of the flow-velocity waveform of the hepatic vein (HV). We decided the Doppler-Pressure (DP) ratio using electrocardiography, the HV Doppler waveform and HV pressure curves, and we calculated the DP ratios. In animal models, the mean DP ratio was 1.04 in controls, 0.68 in cirrhosis, and 1.22 in fatty liver. There were significant differences among these groups (p < 0.005). In the clinical study, the mean DP ratio was 1.03 in controls, 0.95 in chronic hepatitis and 0.79 in cirrhosis. The DP ratio in the Cirrhosis Group was significantly different from that in the Control Group (p < 0.001) and that in the Chronic Hepatitis Group (p < 0.05). We conclude that the DP ratio is decreased in certain hepatic disease states.

Clinical application of hepatic venous hemodynamics by Doppler ultrasonography in chronic liver disease.

The phase differences of the hepatic vein (HV) Doppler waveform might be influenced by fibrosis and steatosis of the liver when using HV Doppler and pressure curve analysis. Because HV catheterization is invasive, we have advocated the noninvasive comparative index (QXs ratio) of the HV Doppler waveform phases recorded simultaneously with electrocardiography and phgonocardiography. Forty-three controls and 169 patients with a variety of liver diseases were enrolled in this study. The mean QXs ratio was 0.75 in the controls, 0.6 in the chronic hepatitis patients, 0.45 in the cirrhosis patients, and 0.90 in the fatty liver patients. There were significant differences between all pairs of these groups (p < 0.001). The QXs ratio may be used to assess the degree of hepatic fibrosis or steatosis.

Analysis of factors affecting the graft oxygenation state in living related liver transplantation.

BACKGROUND/AIMS: In liver transplantation, graft dysoxia after reperfusion may lead to graft failure. The aim of this study is to investigate the relationship between the factors, which were supposed to affect the oxygen supply to the graft, and the oxygenation state of the graft in order to determine which factor is important to prevent the graft from dysoxia. MATERIALS AND METHODS: The relationship between oxygen supply and oxygenation state of the graft was investigated in 56 successful cases of living related liver transplantation. Factors affecting the oxygen supply to the graft were considered as follows; portal venous flow (PVF), mean velocity of the hepatic artery (HA-Vm), hemoglobin concentration in the peripheral blood (Hb), size of the graft liver relative to the recipient body weight (G/R ratio), partial oxygen pressure in the arterial blood (PaO2), and rate-pressure product (BP*PR). Oxygenation state of the graft was estimated by oxygen saturation of hemoglobin in the graft tissue (graft SO2) as measured by tissue near infrared spectroscopy. RESULTS: 1) Graft SO2 was rather independent of PVF and HA-Vm probably due to compensatory interrelation between the portal venous flow and hepatic arterial flow. 2) Significant correlation between G/R ratio and graft SO2 was observed after portal reflow (p < 0.01), but the correlation diminished after hepatic arterial reflow. Positive correlation between G/R ratio and AKBR after portal reflow suggested that the graft with large G/R ratio is likely to suffer dysoxia early after reperfusion. 3) Graft SO2 was positively correlated with Hb (p < 0.05), while there was no significant correlation between graft SO2 and PaO2 or BP*PR. CONCLUSION: This study clarified the contribution of the factors which were supposed to affect the oxygen supply to the graft and the oxygenation state of the graft, and which factor is important to prevent the graft from dysoxia.

Influence of spontaneous portosystemic collateral pathways on portal hemodynamics in living-related liver transplantation in children. Doppler ultrasonographic study.

We investigated the influence of spontaneous portosystemic collateral pathways on the portal hemodynamics and examined the necessity for ligating these vessels in pediatric liver transplantation from living donors. We assessed portal blood flow before, during, and after surgery in 82 pediatric recipients (mean age, 4.2 years), using Doppler ultrasonography. When blood flow in the reconstructed portal vein was decreased (< 10 ml/min/kg body weight) and portosystemic collaterals persisted during surgery, those vessels were ligated and Doppler flowmetry was examined again. Spontaneous portosystemic collaterals were detected at one or more sites in 67 patients before transplantation. These collaterals had been ligated in 17 patients before intraoperative flowmetry. Among the remaining 50 patients, initial Doppler studies revealed a decrease in portal blood flow in 22 patients. Nine patients had hepatofugal splenic venous flow and 6 had no significant flow signals from the intrahepatic portal vein. Ligation of collaterals resulted in a remarkable increase in portal blood flow in 20 patients, all of whom are alive. The remaining 2 patients died of graft failure due in part to portal hypoperfusion. On the other hand, the collaterals were not ligated in 24 patients because adequate portal blood flow was confirmed by intraoperative flowmetry. Postoperatively, flow signals from the unligated collateral vessels gradually diminished, but they still persisted in 3 patients at 12 months after transplantation. Hepatofugal blood flow through the portosystemic collateral pathways may persist after implantation of a normal graft. If the patent collaterals significantly reduce the effective portal blood flow, these vessels should be ligated in order to avoid graft failure.

Vascular complications in living related liver transplantation detected with intraoperative and postoperative Doppler US.

BACKGROUND/AIMS: The purpose of this study was to clarify changes in the graft hemodynamics induced by vascular complications in living related liver transplantation. METHODS: This study included 46 pediatric recipients who underwent partial liver transplantation from living related donors. The blood flow was evaluated in the portal system, the hepatic artery and the hepatic vein with serial intra- and post-operative Doppler ultrasound (US). RESULTS: In 12 patients, intraoperative Doppler US showed a decrease in portal venous inflow (< 9 ml.min-1.kg-1) toward the liver graft and could act as a guide for ligation of collaterals in seven patients, portal re-construction in two, thrombectomy in one and relief of hepatic venous outflow obstruction in two for increasing the portal venous inflow. In five patients, intraoperative Doppler US showed poor arterial inflow, i.e. dampened arterial waveforms which involved both low pulsatility index (< 0.90) and low peak-systolic velocity (< 31 cm/s). In three of them, the waveform was more pulsatile after re-anastomosis or relief from stretching of the hepatic artery. The remaining two patients developed hepatic artery thrombosis. Most of the hepatic venous outflow obstruction (four of five patients) had flat waveforms, low flow velocity (< 10 cm/s) of the hepatic vein, and poor portal inflow (flow velocity < 14 cm/s). Postoperative Doppler US showed hepatic venous outflow obstruction in three patients, hepatic artery thrombosis in three (twice in one patient), portal vein stenosis in two and portal vein thrombosis in one. These complications were successfully managed with surgical procedures in three patients, transhepatic angioplasty in three and conservative treatments in four. Six patients died of non-vascular complications. CONCLUSIONS: Serial intra- and post-operative Doppler US was a useful technique for making an early diagnosis of abnormal hemodynamics of the graft circulation. Furthermore, intraoperative Doppler US could assess reconstructed vessels objectively and would reduce the incidence of vascular complications following transplantation.

Recovery of graft circulation following percutaneous transluminal angioplasty for stenotic venous complications in pediatric liver transplantation: assessment with Doppler ultrasound.

Percutaneous transluminal angioplasty was performed for venous stenosis after living related liver transplantation in three children. Two of them had hepatic vein stenosis and one had stenosis of both the hepatic and portal veins. Progressive development of ascites and deterioration of liver function were found in all cases. Serial Doppler ultrasound studies showed that the flow velocity in the hepatic vein gradually decreased with a flattened velocity waveform, followed by a decrease in portal blood flow. After a successful hepatic vein angioplasty, the velocity in the hepatic and portal veins increased and the Doppler waveform in the hepatic vein became pulsatile in two cases. In the remaining case, a remarkable recovery of both graft perfusion and clinical findings was achieved via combined hepatic vein and portal vein angioplasty. We conclude that balloon angioplasty is an effective alternative to surgery for post-transplant vascular stenosis and that Doppler ultrasound is useful in monitoring graft circulation.

Effects of dobutamine on hepatosplanchnic hemodynamics in patients with chronic liver disease.

BACKGROUND: It is said that catecholamines increase hepatic blood flow in patients without liver diseases, although several reports have suggested a blunted response to catecholamines in patients with liver cirrhosis. METHODS: We investigated changes in splanchnic blood flow distribution induced by the infusion of dobutamine into peripheral veins of healthy adults (NC group), patients with chronic hepatitis (CH group), and patients with liver cirrhosis (LC group), using a Doppler duplex system (protocol 1). We also investigated changes in hepatic hemodynamics induced by dobutamine infusion in patients with liver cirrhosis (cirrhosis group) and patients without liver diseases (control group), using hepatic catheterization (protocol 2). RESULTS: In protocol 1 the average increase in portal venous blood flow during dobutamine infusion was significant in the NC and CH groups but was not significant in the LC group. Changes in the blood flow in the splenic artery and vein, superior mesenteric artery and vein, and femoral artery were similar to those in the portal vein in each of the three groups. Infusion did not cause a change in the common hepatic arterial flow in any of the three groups. In protocol 2 the portal venous flow, cardiac index, and hepatic venous pressure gradient increased significantly during dobutamine infusion in both the cirrhosis and the control groups. Hepatic vascular resistance in the cirrhosis group increased slightly, whereas, in contrast, that in the control group increased significantly. The rate of change in almost all variables was lower in the cirrhosis group than in the control group. CONCLUSION: These results indicate that dobutamine has less effect on hepatic circulation in patients with liver cirrhosis than in those without liver diseases, indicating that the value of dobutamine in increasing hepatic blood flow in cirrhotic patients is very limited.

Distribution of mesenteric and splenic blood flow in cirrhosis of the liver as estimated by radionuclide angiography.

We used radionuclide angiography following an injection of 185 MBq Tc-99m tin colloid as a non-invasive method for measuring the mesenteric and portal components of the total hepatic circulation, according to the method of Fleming et al (J Nucl Med 24; 1983). Fifty-seven patients with cirrhosis and 33 controls were examined. The relative mesenteric flow (MF) and the relative portal flow (PF) were 68.6 +/- 8.5% and 78.6 +/- 5.9%, respectively, in the control group. These values were 42.0 +/- 16.4% and 70.9 +/- 8.9%, respectively in the cirrhosis group, and were significantly lower than in the controls. In the cirrhosis group, the reduction in PF was small, while that in MF was large. Consequently, we found that portal blood flow was relatively well maintained in the cirrhosis patients, while the contribution of splanchnic blood flow to the portal flow was relatively reduced.

Transcatheter hepatic arterial drug infusion therapy for hepatocellular carcinoma. Effect on the arterial ketone body ratio.

The arterial ketone body ratio (acetoacetate to beta-hydroxybutyrate) was measured in 15 patients with chronic liver disease before and after the infusion of anticancer drugs or embolic agents (gelatin sponge or iodized oil) into the hepatic artery. The arterial ketone body ratio decreased after hepatic angiography and decreased further at 15 min after infusion therapy. When the arterial ketone body ratio decreased to 1.0 or less on at least one occasion after infusion therapy, the ratio after hepatic angiography was always 1.35 or less. Such patients developed marked systemic symptoms like fever and severe liver dysfunction. Ascites also developed in three patients in whom the arterial ketone body ratio was reduced to 0.7 or less at 24 h after infusion therapy. The arterial ketone body ratios improved at 3-7 days after infusion therapy. In the seven patients treated with gelatin sponge embolization, the ratio at 3-7 days after therapy was actually higher than that before angiography.

Relief of hepatic vein stenosis by balloon angioplasty after living-related donor liver transplantation.

We have experienced 5 hepatic vein stenoses in 3 children (8 to 23 months old) after living-related liver transplantation (total 48 liver transplants for 48 children between June 1990 and November 1992). The initial symptoms of hepatic vein stenosis were ascites and/or edema. The blood flow of hepatic vessels was monitored by duplex sonography. The mean velocity of the hepatic vein and the portal vein was decreased and flow wave pattern of the stenotic hepatic vein was flat. The patients were treated by percutaneous transhepatic balloon angioplasty. After a successful angioplasty, the mean velocity of the hepatic vein and portal vein increased and pulsatile waves returned to the hepatic vein. Arterial ketone body ratio (acetoacetate/3-hydroxybutylate) increased, promptly followed by recovery of other liver function tests. In 1 patient, this complication occurred three times with intervals of 7 months and 3 months between episodes of hepatic vein stenosis. In conclusion, hepatic vein flow should be monitored routinely with duplex sonography after living-related donor liver transplantation. Percutaneous transhepatic balloon angioplasty is a primary treatment for the stenosis.

Use of proton nuclear magnetic resonance spectroscopy of plasma in screening for malignant disease.

In 1986, narrow plasma proton nuclear magnetic resonance (NMR) methyl and methylene line widths were reported to be associated with malignant disease, but more recent studies have not confirmed this relationship. The authors analyzed 106 plasma samples from healthy control subjects and patients with cirrhosis, hepatocellular carcinoma, metastatic liver tumors, other untreated cancers, and hyperlipidemia. NMR spectroscopy was performed using a proton NMR spectrometer operating at 399.65 MHz. A significant difference was found between the mean line widths of the plasma methyl resonances in control subjects and those in patients with cancer or hyperlipidemia. However, no significant difference was found between the mean plasma methylene line widths in control subjects and patients with cancer. Plasma samples from patients with liver disease or hyperlipidemia showed a characteristic methylene spectral pattern. The methylene pattern could be separated into three types: type A had a small peak on the right shoulder of the main peak; type B was a sharp single peak; and type C was a broad single peak. All control subjects had type A pattern; patients with liver disease had type C pattern; and patients who had hyperlipidemia had type B pattern, and hyperlipidemia may affect methyl and methylene line widths in NMR spectra. Because the methyl and methylene levels and their average line widths correlated inversely with triglyceride levels, considering the spectral patterns that indicate hyperlipidemia should decrease false-positive results and make the methyl line width useful for cancer screening.

Photodynamic therapy using pheophorbide-a and Q-switched Nd:YAG laser on implanted human hepatocellular carcinoma.

To evaluate whether administration of pheophorbide-a, a new photosensitizer, followed by use of Q-switched Nd:YAG laser produces a photodynamic reaction, we administered pheophorbide-a to female nude mice (BALB/c-nu) that had been implanted with human hepatocellular carcinoma. Intra-tumoral concentrations of pheophorbide-a were measured by high-performance liquid chromatography. 3 hours after peroral administration of 1 mg/kg body weight, the intra-tumoral concentration was too low to reveal photodynamic effects. Peroral administration of 250 mg/kg body weight, intra-peritoneal administration of 5 mg/kg body weight, and intra-tumoral injection of 200 micrograms yielded 0.24 micrograms/g, 0.83 micrograms/g and 3.68-108 micrograms/g tumor concentrations, respectively. All tumors were irradiated interstitially using a Q-switched Nd:YAG laser at 1064 nm. Only tumors that had been intra-tumorally injected had areas of necrosis larger than those in control tumors. The results suggest that the injection of pheophorbide-a followed by interstitial irradiation using a Q-switched Nd:YAG laser does not induce sufficient photodynamic reaction if the intra-tumoral pheophorbide-a concentration is less than 0.83 micrograms/g tumor tissue, and that photodynamic therapy may be useful if the pheophorbide-a tumor concentration is within the range of 0.83-108 micrograms/g.

Changes in portal blood flow consequent to partial hepatectomy: Doppler estimation.

Hemodynamic changes in portal blood flow were investigated in 56 patients with hepatic tumors who underwent partial hepatectomy. Portal flow was measured with a Doppler ultrasound system before, during, and after surgery. The portal flow of patients who underwent massive hepatectomy decreased intraoperatively. The portal flow per unit of cardiac output decreased in patients who underwent massive or major hepatectomy, patients with a cirrhotic liver, and patients who had a satisfactory postoperative course. Postoperatively, the portal flow in patients with a poor clinical outcome (multiple organ failure, hepatic failure, and cardiorespiratory failure) decreased significantly. Monitoring portal hemodynamic values appears to be useful in providing an index of "hepatic functional reserve." Adequate portal flow is essential for postoperative hepatic regeneration; changes in portal hemodynamic values may be directly related to the patient's ability to survive surgery and to regain or maintain normal liver function.