Portal blood flow: measurement with MR imaging

Portal blood flow was measured by means of direct bolus imaging (DBI), a method of measuring flow velocity with magnetic resonance imaging. DBI allows immediate visualization of fluid movement, thereby enabling calculation of a flow velocity from fluid displacement. In a study of 14 healthy male volunteers, portal blood flow was measured with electrocardiographic gating during the 18 seconds subjects could suspend respiration. These measurements showed a close correlation (r = .968) with those obtained by means of Doppler ultrasound (US). Increases in portal blood flow after oral administration of ethanol and glucose were measured with DBI. Glucose caused a statistically greater increase in portal blood flow volume in healthy control subjects than in patients with chronic hepatitis. Blood sugar, on the other hand, showed a significantly greater increase in these patients, possibly reflecting the greater vascular resistance of the liver. DBI is a useful noninvasive method of measuring portal blood flow without the limitations imposed on Doppler US by obesity and intestinal gas.

[Effect of vasopressin on rabbit hepatic energy metabolism evaluated using in vivo P-31 magnetic resonance spectroscopy]

Changes in metabolic state of rabbit livers after administration of vasopressin (10 mU/kg/min d.i.v.) were evaluated using in vivo P-31 magnetic resonance (MR) spectroscopy. Targets were nine normal control rabbits and eight with chronically carbon tetrachloride-damaged livers. A 2.0 Tesla whole-body MR imager was used for measurement. After administration of vasopressin, liver spectroscopy showed a mild ischemic pattern. The inorganic phosphate peak increased statistically significantly (p less than 0.05) both in the normal control group and in the damaged-liver group (20% and 16% above base line value respectively). In the normal control group, there was a statistically significant decrease (p less than 0.05) in the ATP peak to 18% below the base line value while the PME (phosphomonoester) peak increased slightly (about 10%); there was little change in the damaged-liver group. It was thought that the difference between the two groups was due to differences in blood flow mechanism and liver metabolism. Magnetic resonance spectroscopy was considered to be useful in studying the detailed changes in metabolic state of rabbit liver after administration of vasopressin.

[Experimental study of periodontal tissue regeneration using biodegradable membranes]

This study was designed to investigate the effect on new attachment formation using a biodegradable membrane as a barrier to the regeneration of periodontal tissue. One-wall wide periodontal osseous defects with exposed root surfaces were prepared in three adult mongrel dogs. After surgical debridement of the periodontal defects, 3 types of biodegradable membranes, [Poly(L-lactic acid); (P-L-LA)] membrane, [Poly(lactic acid-co-glycolic acid); (PLGA)] (81: 19 mole%) membrane and PLGA (50: 50 mole%) membrane, were arranged to cover the denuded root surfaces. Specimen blocks were removed 8 weeks postoperatively for histological evaluation of their effect on the regeneration of periodontal tissue. The results were as follows: 1. Gingival regions containing P-L-LA or PLGA (81: 19 mole%) membranes showed delayed wound healing macroscopically. 2. Almost all P-L-LA membranes were present in the experimental sites failing to be resorbed during the 8-week experimental period. PLGA (81: 19 mole%) membranes were also present but showed with some degree of resorption and fragility, while PLGA (50: 50 mole%) membranes were completely resorbed. 3. This showed that the membranes used in this experiment are possible barriers to the generation of new attachment. It is important to make sure keeping the membrane. 4. There was no relationship between osteogenesis and cementogenesis. It seems that osteogenesis was depressed by membrane shrinkage and the gingival pressure which limited "the regenerative space of bone." 5. Moderate resorption was observed on the root surface, and new cementum was formed at the resorbed surface. 6. Ankylosis was observed between the new cementum and bone at the experimental sites. Newly formed cementum was seen on coronal sections of this area.

[Measurement of portal blood flow with magnetic resonance imaging]

A new method for measuring portal blood flow using magnetic resonance imaging has been developed. Flow velocities are calculated from distances that are directly visualized using a new pulse sequence. In a phantom study, the measured flow rates showed a close correlation (r = 0.9996) with actual flow rates in the range 4.7 cm/sec to 22.8 cm/sec. In a study using volunteers, portal blood flow was quickly measured (about 18 seconds) using electrocardiographic gating. These measurements were compared with those obtained by Doppler ultrasound, with which they showed a close correlation in flow velocity (r = 0.968) and flow volume (r = 0.936). This method allows reasonably accurate quantitative analysis of portal blood flow in patients in whom the Doppler method can not be used because of obesity or intestinal gas.

Central signals of gallstones in magnetic resonance imaging

The magnetic resonance imaging of gallstones was studied in 34 patients. Diagnosis of the gallstones using magnetic resonance imaging was possible in 29 patients (85%). The gallstones showed as no-signal areas in all cases, with relatively strong signals being detected from the center of the stones in six cases. Postoperative studies showed the stones with the central signals to be of the so-called mixed stone type, in which the central area consists of cholesterol with a radiating structure. The central signal was thought to originate in water that accumulates in the central cavity of the stone, the cavity not being isolated from the exterior of the stone and there being a passage of fluids. The central signal is a characteristic indication of the stone's structure.

Portal hemodynamics in patients with hepatocellular carcinoma

The protal blood flow was assessed in 46 patients with hepatocellular carcinoma, 81 with cirrhosis, and 110 control subjects using an ultrasonic B-mode pulsed Doppler duplex system. The cross-sectional area of the portal vein was increased, and the velocity of portal blood flow was decreased in hepatocellular carcinoma and cirrhosis, whereas the blood flow volume was not significantly different. A significant decrease in portal blood flow was found in hepatocellular carcinoma only when at least three of the four major branches of the portal vein were occluded. The change in portal hemodynamics before and after transcatheter arterial embolization (TAE) was investigated. Immediately after TAE, neither portal venous pressure nor portal blood flow showed any constant trend. The portal blood flow reached a peak 1 week after TAE and then returned to its former value after 3-4 weeks, while all cases with poor prognoses showed a drop in portal blood flow after TAE.

Dietary risk factors of stroke and hypertension in Japan -- Part 2: Validity of urinalysis for dietary salt and protein intakes under a field condition

Utility of urinalysis as a method for estimating dietary salt and protein intakes was examined in volunteers from farming and fishing villages in Japan and the data was compared to findings in a survey on diets. We found that partial urine samples and even a fasting single spot urine in the a.m. could serve as valid substitutes for 24-hour (hr) urine collections. Further, significant correlations were obtained between levels of salt in the diet estimated by survey interviews and urinary sodium (Na) and between interview-estimated dietary total or animal protein and urinary inorganic sulfate (SO4). In comparative studies between farming and fishing villages, almost the same findings, higher salt in a farming village and higher animal protein in a fishing village, were obtained in the urinalysis and the survey on diets. These findings clearly indicate that urinalysis, as a method for estimating dietary salt and protein intake in population surveys, has distinct advantages.

Dietary risk factors of stroke and hypertension in Japan -- Part 1: Methodological assessment of urinalysis for dietary salt and protein intakes

In our attempt to design a method which would be more reliable than dietary survey interviews when estimating salt and protein intakes in a population survey, a urinalysis-related study was done on volunteers. Urinary sodium (Na), urea nitrogen (UN) and inorganic sulfate (SO4), all indices of dietary salt, protein and sulfoamino acids, respectively, were confirmed to reflect the nutritional condition. Interaction between salt and protein was not observed at least at the dietary levels used in the present study (for salt, 0.33 and 0.1 g/kg body weight/day; for protein, 1.6 and 0.7 g/kg body weight/day). Excretion of components was delayed several days or more after dietary ingestion, and nutritional estimation by urinalysis, therefore, may not be so much affected by daily variables in the diet intake. Further, partial urine samples proved to have a highly significant correlation with 24-hour (hr) urine, as for urinary Na, potassium (K), SO4, UN and their creatinine (Cr) ratios, thus indicating the availability of partial urine samples as substitutes for 24-hr urine specimens. Thus, urinalysis is a more readily facilitated, more scientific and more quantitative method for epidemiological nutritional surveys.

Dietary risk factors of stroke and hypertension in Japan -- Part 3: Comparative study on risk factors between farming and fishing villages in japan

General medical examinations were performed in two rural areas of Shimane Prefecture in Japan, one was a farming village and the other a fishing village where incidences of death due to stroke differed, higher in the former and lower in the latter. Comparisons were made on salt and protein intake by analyzing the fasting single spot urine collected in the morning and by blood tests. Urine samples were analyzed for sodium (Na), potassium (K), urea nitrogen (UN), inorganic sulfate (SO4) and creatinine (Cr) and blood samples for cholesterol (Chl), triglyceride (TG), hematocrit (Ht) and hemoglobin (Hb). Blood pressure, Na/Cr, Na/K and Ht were higher in the farming village and K/Cr, UN/Cr, SO4/Cr, SO4/UN, Chl and TG were higher in the fishing village. These findings indicate the higher salt intake and lower intake of K, animal protein and fat in the farming village. This typical dietary pattern of the Japanese may explain the higher incidence of hypertension and stroke in the farming village.

[Clinical evaluation of cefmetazole in the dermatologic field]

The therapeutic efficacy and safety of cefmetazole, a cephamycin-derived antibiotic in an injectable form were evaluated in patients with pyogenic infection in the dermatological field. Especially, it was found to be extremely effective for the skin diseases due to staphylococci or streptococci. The results obtained were the following; marked improvement in 18 cases and moderate improvement in 34 cases out of 61 cases, attaining efficacy of 86.7%. Side effects were noted as the rise of GOT and GPT in 3 cases, which were normalized by ceasing its further administration. The MIC of cefmetazole against Staphylococcus aureus isolated out of foci was 0.39-6.25 microgram/ml, while those of CEZ, CXM and ABPC used as the controls exceeded 50 microgram/ml in some cases. It is considered thus, that cefmetazole, is superior to these other antibiotics also in terms of MIC.