U-shape rotating anti-cathode compact X-ray generator: 20 times stronger than the commercially available X-ray source.

A new type of U-shape anti-cathode X-ray generator in which the inner surface of a cylindrical target is irradiated by an electron beam has been made by modifying a conventional rotating anti-cathode X-ray generator whose brightness in the catalog is 12 kW mm(-2). The target material (Cu), target radius (50 mm) and rotating speed (6,000 r.p.m.) were not changed in this modification. A brightness of 52 kW mm(-2) was obtained by this U-shape-type X-ray generator. This means that the brightness of the new type is 4.3 times greater than that of the old unmodified one. Furthermore, the new-type X-ray generator yielded a brightness of 129 kW mm(-2) by adding a carbon coating on the Cu target. This means an overall increase of brightness of ten times. The original generator has the highest brightness in the generators of the same class (having a radius of 50 mm and rotation speed of 6,000 r.p.m.). Observations showed that Cu Kα counts at vertical incidence of the electron beam onto the surface of the new target, which is initially optically smooth, decrease as the surface is roughened by a severe thermal stress caused by strong electron beam exposure. Further observation reveals, however, that oblique incidence of the electron beam onto the roughened surface drastically increased the X-ray output and amounts to twice as much as that from a smooth surface at vertical incidence. Thus, at the present stage, an overall increase of brightness has been realised at a level 20 times stronger than that of the original commercially offered X-ray generator that we modified.

[Urethral injury with unusual clinical course: a case report].

A 20-year-old men fell from a ladder in 1995, striking his perineum strongly, and macroscopic hematuria with painful urination lasted for several days. Subsequently, swelling of the perineum on urination continued to occur. However, he did not seek medical treatment until July 1997, when he consulted our medical institution. A diverticulum-like change was found in the bulbous urethra on urethrocystography, and a tear in the same position on urethroscopy. On September 22, 1997, surgery was performed after constructing a cystostomy, the tear was located using a urethroscope, and closed through a perineal approach. At 14 days after surgery, there was extra-urethral leakage of contrast media on voiding cystourethrography, and at 28 days after surgery, the findings showed improvement. Since then, he has been free of the preoperative symptoms.

[A case of synchronous triple primary cancers of prostate, kidney and bladder].

A case of synchronous triple primary cancer occurring in the prostate, kidney and urinary bladder is reported. A 74-year-old man had been complaining of macroscopic hematuria, dysuria and residual sensation of urine since January 1994. Pathological analysis of prostate revealed poorly differentiated adenocarcinoma in March, 1994. Bone and Ga scintigraphy gave no evidence of metastasis. Computerized tomography (CT) revealed irregularity of a part of the margin of prostate (T2N0M0) and enhanced mass with a diameter of 3 cm localized at the hilus of the right kidney. Excretory urography showed a shadow defect in the right pelvis and elevation of the bladder base. In spite of the appearance of class 5 in urine cytology, no tumor was detected in the bladder by cystoscopy. Angiography confirmed the presence of a hypervascular tumor in the right kidney. He underwent right-sided nephroureterectomy in April, 1994, because not only right pelvic tumor but also right renal tumor was suspected. Histological examination of the renal tumor revealed clear cell carcinoma (T2N0M0). Then, he did not visit our hospital for 8 months. In January, 1995 a papillary broadbase tumor was found near the bladder neck by cystoscopy. Transurethral resection of the tumor (TUR-Bt) was performed in February, 1995. Pathological analysis of the tumor revealed TCC G1 pT1 (T1N0M0).

Reconstruction for the brilliance-upgrading project of the Photon Factory storage ring.

Reconstruction of the Photon Factory storage ring (PF ring; 2.5 GeV) is now in progress to provide very brilliant synchrotron radiation to users, i.e. the emittance is being reduced by a factor of five. Components, such as the quadrupole and sextupole magnets, vacuum chambers, beamlines and beam-position monitors, are being replaced by new ones in 16 normal-cell sections of the PF ring. The accelerating cavities, injection systems and control systems are also being replaced. Operation will commence when the improvements are completed on 1 October 1997.

Different modulation of protein kinase C isozymes in dibutyryl cyclic AMP-differentiated PC12h cells.

PC12h cells can be differentiated into sympathetic neuron-like cells by various agents, including nerve growth factor, basic fibroblast growth factor, cyclic AMP analogues, and protein kinase C (PKC) activators. To study the involvement of PKC in the process of PC12h cell differentiation by cyclic AMP treatment, PKC isozymes (alpha, beta I, beta II, and gamma) were analyzed using column chromatography and immunoblotting. Two PKC isozymes, PKC(alpha) and PKC(beta II), were predominantly detected in PC12h cells. When stimulated by dibutyryl cyclic AMP, PKC(alpha) levels declined in the cytosolic fraction of the cells, whereas PKC(beta II) levels increased. Increased PKC(beta II) levels were also detected in the particulate fraction, whereas particulate PKC(alpha) levels did not change. The total PKC activity decreased in the cytosolic fraction following cyclic AMP stimulation of PC12h cells, whereas it stayed constant in the particulate fraction. Fractionation on a hydroxyapatite column showed a decreased level of PKC(alpha) activity and a transient increase followed by a decreased level of PKC(beta II) activity. This discrepancy between increased PKC(beta II) immunoreactivity and reduced PKC(beta II) activity suggested the presence of nonactivatable PKC(beta II) in cyclic AMP-treated PC12h extract. These findings indicate that PKC(alpha) and PKC(beta II) are differentially regulated during the differentiation of PC12h cells. In addition, the differentiation of PC12h cells triggered by cyclic AMP seems to involve characteristic alterations of PKC isozymes.

[Study on free enzymes and proteins in the urine. Report IV: The effects of Iohexol on elderly patients with renal function disorder].

We assessed the nephrotoxicity of a non-ionic contrast medium, Iohexol, in 18 elderly patients. They were divided into two groups. Group 1 consisted of 12 patients with glomerular flow rate (GFR) above 60 ml/min/1.73 m2 (range 69-136; average 96) and group 2 consisted of 6 patients with GFR below 60 ml/min/1.73 m2 (range 38-59; average 49). Urine samples, collected before, immediately after, and on the third and sixth days after drip infused pyeloureterography (DIP) were analyzed for gamma-glutamyl transpeptidase (gamma-GTP), N-acetyl-beta-D-glucosaminidase (NAG), beta 2-microglobulin (beta 2-MG) and albumin. In group 1, immediately after DIP, the urinary excretion of albumin, gamma-GTP and NAG were significantly increased (p < 0.01, p < 0.01, p < 0.01). In group 2, immediately after DIP, the urinary excretion of gamma-GTP and beta 2-MG were significantly increased (p < 0.01, p < 0.1). The gamma-GTP and NAG values in both groups suggest that the damage of proximal tubules cells will not continue for more than 4 days. However, as for the reabsorption of beta 2-MG on proximal tubules, in group 2 the value did not return to the pre DIP level until 6 days after DIP. We believe it is important to postpone injection of non-ionic contrast medium within 6 days of its last usage.

[The use of a metallic stent in 32 patients with benign prostatic hypertrophy. Preliminary results and 3 months of follow-up].

A prospective noncontrolled study of the safety and potential efficacy of the metallic stent was performed on 32 patients with benign prostatic hypertrophy. Mean age was 76.6 years (range, 56-98 years), and mean prostatic volume was 24.2 cm3. The patients were selected on the basis of a quantitative symptom score (QSS), uroflowmetry measurements, and residual urine volume (RU). Nineteen patients had urinary retention and remaining 13 patients had moderate symptoms and signs of prostatism. Placing the stent was successfully done in 31 patients (97%). It took 15 minutes to place the stent using transabdominal and/or endorectal sonography. After 3 months, 27 patients (87%) showed improved QSS. In patients with dysuria, maximum flow rate (MFR) and RU before treatment were 6.9 +/- 1.7 ml/sec and 112.3 +/- 61.8 ml, respectively. After treatment, they improved to 12.3 +/- 2.7 ml/sec and 12.7 +/- 6.7 ml, respectively. On the other hand, all patients who had urinary retention were able to urinate just after treatment, and MFR and RU were 12.9 +/- 3.6 ml/sec and 24.4 +/- 43.3 ml, respectively. Evaluation on the basis of improvement in MFR and reduction in RU showed that the stent was effective in 71% of total patients (22 out of 31 patients), 94% of the patients with urinary retention (17 out of 18 patients). The overall clinical efficacy of this stent was 68% (21 patients). There were no major complications such as urge incontinence and urinary tract infection during follow-up. Although proximal migration of the stent was observed in 6 patients, the stent could be taken out and replaced in 4 patients. From the above results, we conclude that the metallic stent is useful for the treatment of prostatism and urinary retention.

Mechanism of dialysis-induced hypotension.

Dialysis-induced hypotension, the sharp decrease in blood pressure occurring during hemodialysis, remains one of the most difficult problems associated with hemodialysis even today. However, there is yet no established theory to explain the mechanism triggering dialysis-induced hypotension. This review attempts to offer a consistent and cohesive source of information on the hemodynamics during dialysis-induced hypotension, and then analyzes etiologic factors in such hypotension reported by various investigators. Finally, three hypotheses concerning the mechanism of dialysis-induced hypotension including our own are introduced.

Effects of excess factor D on early- and late-phase activation of the complement cascade.

The present study was undertaken to examine the effects of excess factor D build-up in the body of end-stage renal disease (ESRD) patients upon the activation of the alternative pathway and the terminal pathway in the fluid phase. First, to clarify the effect of excess factor D on the alternative pathway, purified factor D from an ESRD patient was added to normal serum and the changes in concentrations of C3a-des-Arg and C5a-des-Arg were investigated. The results showed that once the serum factor D level reached a concentration corresponding to 15 micrograms/ml in the serum of the ESRD patient, the C3a-des-Arg and C5a-des-Arg levels had climbed to about 1.7-fold the concentration in normal serum. Next, in order to clarify the effect of excess factor D on the terminal pathway, purified factor D was added to normal serum, and the changes in C5b6 generation were examined. The results indicated that as the factor D level increased in the serum, the C5b6 level rose gradually also; and when the factor D concentration reached 15 micrograms/ml, the C5b6 generation had risen to approximately 1.5-fold the level in normal serum. The present results therefore suggest that factor D build-up in ESRD patients provides a uremic toxin that can cause abnormal activation of the whole complement cascade.

Induction of irreversible glomerulosclerosis in the rat by repeated injections of a monoclonal anti-Thy-1.1 antibody.

The present experiment demonstrated that an irreversible glomerulosclerosis could be induced in the rat through repeated intravenous administrations of OX-7 (a monoclonal anti-Thy-1.1 antibody). Rats were injected with 0.2 mg of affinity-purified OX-7 at 1-week intervals for a period of 4 weeks. Glomerular damage was periodically examined at light-microscopic level. Thirty-five days after the initial injection (7 days after the final injection), capillary aneurysms and expansion of the mesangial areas with hypercellularity were frequently observed. Similar glomerular damage was also observed in rats 7 days after they received a single injection of either 1.0 or 0.2 mg of OX-7. After repeated injections, 112 days from the initial administration (84 days after the final injection), approximately 60% of the glomeruli had expanded mesangial areas with an apparent increase in the mesangial matrix. The result contrasts sharply with that obtained from a single injection of OX-7 in that more than 85% of the glomeruli showed no abnormalities 84 days after the injection. This chronic model, as a result of repeated injections of the antibody, could serve as a potential for further investigation of the mechanisms involved in the development of chronic glomerulonephritis.

[The coefficient of variation of RR intervals (CVRR) on electrocardiogram in patients with essential hypertension with reference to aging, hemodynamics and sympatho-adrenomedullary function].

To evaluate the significance of parasympathetic nerve activity in essential hypertension, we measured the coefficients of variation of RR intervals (CVRR) on electrocardiogram and examined the relationships between CVRR and aging, hemodynamics and sympatho-adrenomedullary function in normotensive subjects (NT) and in patients with essential hypertension (EHT). Mean arterial pressure (MAP), heart rate (HR), plasma noradrenaline concentration (pNA), plasma adrenaline concentration (pAd) and CVRR resting in a supine position were simultaneously measured in 37 NT (33.8 +/- 2.0 years) and 47 mild-to-moderate EHT (51.3 +/- 1.5 years). In both NT and EHT, significantly negative correlations between CVRR and age (NT: r = -0.54, p less than 0.001, EHT: r = -0.41, p less than 0.005) were observed, however, CVRR correlated with neither MAP, HR nor pAd. CVRR tended to correlate negatively with pNA (r = -0.27, p less than 0.1) in NT, unlike in EHT. The mean value of CVRR in EHT (n = 10, age: 38.3 +/- 1.6 years, CVRR: 3.61 +/- 0.37%) was significantly (p less than 0.005) lower than in age-matched NT (n = 10, age: 38.3 +/- 2.5 years, CVRR: 5.76 +/- 0.45%). These results indicate that the parasympathetic tone suggested by CVRR may be related to aging and sympathetic nerve activity, and that parasympathetic function might be impaired in EHT.

A new treatment strategy using both intermittent short dialysis and continuous ambulatory hemofiltration.

The authors devised a new treatment strategy using continuous ambulatory hemofiltration (CAHF) in between short hemodialyses (short HD). For CAHF, a small wearable hemofilter (0.1 m2) was developed using a membrane permeable to low molecular weight proteins. During short HD, no body water was removed, but saline, equivalent to 3% body weight, was administered at a constant rate. During CAHF, 1 L of replacement fluid was administered intravenously after every meal to increase the replacement volume. Switch from the conventional to new strategy resulted in far more stable blood pressure during short HD, a decrease in time averaged body weight, and a decrease in a decrease in time averaged blood urea nitrogen and plasma beta 2-m levels.

[Renal sodium handling and renal dopaminergic activity in overweight normotensive subjects].

Recently, we reported that the blunted natriuretic ability related to an attenuation of renal dopaminergic activity might play an important role in the hypertensive mechanisms of overweight patients with essential hypertension. On the other hand, the interrelationships between obesity, blood pressure and renal sodium handling in normotensives (NT) have not been clear. The purpose of the present study is to reveal the role of renal dopaminergic activity on renal sodium handling in overweight NT. The study consisted of 52 hospitalized NT receiving a regular diet containing 200mEq of sodium, 75mEq of potassium, 2400kcal/day, who were divided into two groups of 31 non-obese (NNT) and 21 obese (ONT) subjects. NNT was categorized as the body mass index (BMI) less than, and ONT as the BMI equal to or more than, 25kg/m2. In the early morning, after overnight fasting, all subjects remained in a supine state and were examined for renal clearance. During the clearance period, mean arterial pressure (MAP), heart rate (HR), endogenous creatinine clearance (Ccr), urinary excretion of sodium (UNaV), fractional excretion of sodium (FENa) and of inorganic phosphorus (FEP) and urinary excretion of free dopamine (uDA) were determined. There were no significant differences in age, HR, Ccr or UNaV between the two groups. Higher MAP and lower FENa) were observed in ONT than in NNT, but the differences in these parameters were not statistically significant. However, FENa in ONT was significantly lower than in MAP-and Ccr-matched NNT. In addition, FENa correlated negatively with BMI in ONT, unlike in NNT. MAP was correlated positively with FENa, and a similar tendency was found between MAP and FEP in NNT, but not in ONT. On the other hand, there was no significant correlation between BMI and uDA in either NNT or ONT. This result was different from our previous data in patients with essential hypertension (EHT) in which BMI correlated with uDA positively in non-obese EHT and negatively in obese EHT. These findings suggest that blunted natriuretic ability may exist in ONT, and the role of renal dopaminergic activity related to the attenuated natriuretic ability in ONT may be less important than in obese EHT.

[Correlations between the coefficient of variation of RR intervals and sympathetic nerve activity following superior tilting in normotensive subjects and in patients with essential hypertension].

The relationship between changes in sympathetic nerve activity and those in parasympathetic tone with a change in position was investigated in patients with essential hypertension using the coefficient of variation of RR intervals on electrocardiograms (CVRR). Mean arterial pressure (MAP), heart rate (HR), plasma noradrenaline concentration (pNA) and CVRR were measured in a supine position at rest and 20 min after having the head tilted 60 degrees superiorly in 10 normotensives (NT: 51.9 +/- 3.0 yrs) and 7 essential hypertensive patients (EHT: 51.0 +/- 2.8 yrs). After changing the position, CVRR decreased significantly in the NT, but not in the EHT; whereas, significant increases of both HR and pNA without significant changes in MAP were shown in both groups. A significant negative correlation between percentage changes in CVRR (% delta CVRR) and pNA (% delta pNA) were observed in the NT, but not in the EHT. However, there was no relationship of % delta CVRR to % delta MAP or to % delta HR in either group. It was suggested from the changes in CVRR that suppression of the parasympathetic tone, which occurs in the NT group corresponding to sympathetic augmentation to present a decrease in blood pressure with a change in position, may be impaired in the EHT group.

[Shy-Drager syndrome: its autonomic function, alpha 2 receptor density and mechanism of postprandial hypotension].

The autonomic function, platelet alpha 2 receptor (alpha 2R) density, and mechanism of postprandial hypotension were examined in a 58-year-old man with Shy-Drager syndrome (SDS). His chief complaints were orthostatic syncope and impotence. His blood pressure was kept within normal limits in a supine position, but severe hypotension and fainting occurred when he assumed an upright posture. There were diminished sweating response to warm stress, abnormal pupil reactions to drugs, lack of blood pressure elevation at phase IV during the Valsalva maneuver, and a lack of pressor response to hyperventilation and cold stress. The plasma norepinephrine levels (pNE) were very low in a supine position at rest and in a head-up tilt position. Severe blood pressure fall (hypotension) associated with a lack of pNE elevation occurred during an oral glucose tolerance test (oGTT). Platelet alpha 2R density increased and the pressor response to infused norepinephrine (NE-R) was pronounced. The heart rate response to injected atropine was clearly attenuated. The coefficient of the R-R interval variation in the ECG (CVRR), which may reflect parasympathetic activity, was markedly low at rest. In addition, a decrease in a head-up tilt position and increase during oGTT also resolved. These results indicate that a dysfunction of the parasympathetic and sympathetic nervous systems and the up-regulation in the alpha 2R system that leads to an increase in alpha 2R density in SDS are involved in this disease and that the mechanism of postprandial hypotension in SDS may be different from that in normal elderly subjects.

Effectiveness of push/pull hemodiafiltration using large-pore membrane for shoulder joint pain in long-term dialysis patients.

Long-term hemodialysis (HD) patients complaining of shoulder joint pain were treated by HD and by push/pull HDF using high-flux synthetic membranes with large pores (Asahi PAN 20CX2) for 2 weeks. The results showed no significant difference in Kt/Vurea between HD and push/pull HDF. Nevertheless, reduction of the plasma beta 2-microglobulin was greater during push/pull HDF than during HD. These findings can be explained by far more convective flux in push/pull HDF than in HD: nearly 30 L during push/pull HDF vs. 3 L during HD. In the present study, there was no alleviation of the shoulder joint pain during HD treatment, whereas marked relief of the symptom was found during push/pull HDF treatment. Since the two treatment modalities differ simply in their efficiency in removing larger molecular weight substances, the joint pain alleviation effected by push/pull HDF could well be ascribed to elimination of an unknown larger molecular weight substance causing this symptom. However, a considerable amount of beta 2-microglobulin was removed both by HD and push/pull HDF. Therefore, the substance causing the joint pain might be larger than beta 2-microglobulin.

Change in sympathetic activity before, during, and after dialysis-induced hypotension.

During the hemodialyses of eight patients with end-stage renal failure, who often had sudden-onset dialysis-induced hypotension, catecholamine (CA) levels were measured in the ultrafiltrate obtained by a mini-filter placed in series upstream of the dialyzer. The water evaporation rate from the skin (reflecting the perspiration rate) was also monitored. Results showed a temporary elevation in CA levels in the ultrafiltrate before hypotension occurred. This rise did not continue for long, returning to baseline when hypotension actually occurred. The temporary elevation may reflect transient compensation by the sympathetic nervous system for the decrease in vascular wall tension. It was also found that there was considerable water evaporation from the skin during hypotension. Because sweat gland activity is reflexively modulated by the baroreceptor, perspiration after a drop in blood pressure may reflect the normal diminiution in baroreceptor activity.