Search PubMed⌕ Search

Biomedical subjects

K Kihara

Publications and source records attributed to K Kihara.

At least 91 records · Page 5Linked to original sources

Reorganization of the innervation of the vas deferens after sympathetic decentralization.

Reorganization of autonomic efferent pathways to the rat vas deferens was noted after chronic (30 days) sympathetic decentralization produced by hypogastric nerve (HGN) transection. In normal rats, electrical stimulation of the HGN elicited an increase in vasal pressure (VP) bilaterally, whereas pelvic nerve (PN) stimulation did not alter VP. However, after unilateral HGN transection, stimulation of the PN on the transected side but not on the normal side increased VP. The decentralized vas exhibited larger VP responses to stimulation of the contralateral HGN in comparison with the normal vas. After bilateral HGN transection, PN-induced VP responses were elicited at lower stimulus intensities than in rats with unilateral transections. PN-induced VP responses were blocked by hexamethonium and prazosin but were not altered by atropine. Distension of the vas lumen occurred after decentralization. PN-induced VP responses were not detectable in extremely distended vas. These data indicate that, after degeneration of sympathetic preganglionic axons, decentralized adrenergic ganglion cells are reinnervated by parasympathetic or sympathetic preganglionic pathways and that the reinnervation influences vasal function.

Animals↗

[A case of renal cell carcinoma with hyperglycemia].

A 71-year-old male with hyperglycemia was incidentally found to have a right renal tumor. Hyperglycemia had been controlled by administration of 34 units of insulin. Immediately after radical nephrectomy, hyperglycemia was improved to be able to stop insulin. His fasting blood glucose level remained within normal limits without any treatment. Laboratory studies, however, failed to reveal any endocrinopathy derived from renal cell carcinoma responsible for the diabetic state.

Aged↗

[En bloc cystourethrectomy with preservation of potency].

BACKGROUND: The objective of this study is to evaluate efficacy of en bloc cystourethrectomy with preservation of potency in patients with bladder carcinoma. METHODS: A total of nine patients underwent this procedure in 1991 and 1994. Following 2 cases of 1991 who were confirmed to recover potency and had no recurrence in the pelvis during 2-year follow up as a preliminary study, 7 cases underwent the same procedure in 1994. Erectile function was measured by the snap gauge band. RESULTS: Six of the 9 patients recovered erection adequate for sexual activity and 4 of them have practiced sexual intercourse. The remaining 3 patients experienced mild erection but inadequate. One of them failed to accomplish adequate erection because of perineal pain at erection. Three to eighteen months after surgery, the first erection was experienced. Surgical margins were pathologically negative in each of the 9 specimens. By the present, all of the 9 patients survive with no evidence of disease. CONCLUSION: The potency-sparing en bloc cystourethrectomy appears to preserve potency on the level comparable to the two-stage potency-sparing cystourethrectomy combined with delayed urethrectomy.

Adult↗

[Relationship between pretreatment serum levels of prostate specific antigen and bone metastasis in prostate cancer].

We retrospectively reviewed pretreatment levels of serum prostate specific antigen (PSA) in 138 newly diagnosed, untreated patients with prostate adenocarcinoma to evaluate the usefulness of serum PSA levels to predict results of radionuclide bone scans. All of the 24 patients with serum PSA levels above 200 ng/ml showed positive bone scans whereas those with serum PSA levels below 10 ng/ml included only three cases (3/51, 5.1%) positive for bone metastasis. All of the three had poorly differentiated adenocarcinoma of the prostate. In conclusion, bone scans may not be necessary in the cases with serum PSA levels less than 10 ng/ml except for those with poorly differentiated adenocarcinoma.

Adenocarcinoma↗

[Combined hormone-chemotherapy for stage D2 prostatic cancer: starting time of chemotherapy in relation to hormone therapy].

We retrospectively analyzed 29 patients with stage D2 prostatic cancer who had been treated with chemotherapy at the urological clinic of Tokyo Medical and Dental University Hospital between 1983 and 1992 to evaluate the efficacy of chemotherapy for advanced prostatic cancer. The patients were divided into three groups according to the starting time of chemotherapy in relation to hormone therapy; 9 patients who received chemotherapy more than four weeks after the initial hormone therapy (group H), 9 patients who received chemotherapy only or in combination with the hormone therapy more than four weeks previously (group C), and 11 patients in whom both therapies were started within four weeks (group HC). Follow-up period ranged from four to 108 months averaging 35. Combination chemotherapy including cisplatin was administered one to 17 times with the median of five. The five-year survival rates estimated by Kaplan-Meier method were 18% in group H, 28% in group C, and 78% in group HC, respectively (HC vs. C: p < 0.05, HC vs. H: p = 0.059). These findings indicate that a combination chemotherapy including cisplatin may improve the prognosis of patients with advanced prostatic cancer when it is started with the initial hormone therapy simultaneously.

Aged↗

[Rapidly deteriorating adult hydronephrosis due to an aberrant vessel: a case report].

Hydronephrosis due to ureteropelvic junction (UPJ) obstruction generally progresses gradually. We experienced a case of hydronephrosis due to UPJ obstruction deteriorating rapidly in an adult woman. In spite of percutaneous nephrostomy, 99mTc-DTPA renogram showed a non-functional pattern. A nephrectomy was done. Peri-operatively, the aberrant lower pole vessel was found to be obstructing the UPJ. The hydronephrosis deteriorated rapidly because the extrarenal pelvis dilated in the shape of box, became suspended from the aberrant vessel. Therefore, we believe that the box pelvis is one of the most important factors deteriorating hydronephrosis.

Arteries↗

Differential effects of an acyl-coenzyme A:cholesterol acyltransferase inhibitor on HDL-induced cholesterol efflux from rat macrophage foam cells.

When rat macrophages were converted to foam cells with acetylated low density lipoprotein (acetyl-LDL) and then reacted with high density lipoprotein (HDL) and an inhibitor of acyl-coenzyme A:cholesterol acyltransferase (58-035) (sequential incubation system), 58-035 did not enhance HDL-induced cholesterol efflux. In contrast, when macrophages were exposed to acetyl-LDL in the presence of both HDL and 58-035 (simultaneous incubation system), HDL-induced cholesterol efflux was enhanced 1.6-fold by 58-035. Cholesterol efflux with HDL alone was 2-fold greater in simultaneous incubation than in sequential incubation. These results suggest the presence of an efficient cholesterol efflux pathway in simultaneous incubation which is not available in sequential incubation. This pathway, which we refer to as the neutral cholesterol ester hydrolase-independent pathway, is characterized by the efflux of lysosome-derived cholesterol without re-esterification.

Animals↗

Natural killer (NK) and lymphokine-activated killer (LAK) activities in a patient who recovered from cancer, and the characteristics of LAK cells generated from CD4-CD8- and CD8+ peripheral blood lymphocytes.

The natural killer (NK) and lymphokine-activated killer (LAK) activities of a patient who recovered from bladder transitional cell carcinoma were determined. The patient was diagnosed in 1980 and repeated several therapies until 1986. Since 1987, he has been in a tumor-free state. Recently, very high NK and LAK activities were found. The NK activity was recognized not only against the NK-sensitive cell line K562, but also against NK-unsensitive Raji and Daudi cell lines and against autotumor cell line H41. The percentage of CD16+ in peripheral blood lymphocytes (PBL) was 52.9%, the CD8+CD16+ was 26.3%, and the CD4-CD8-CD16+ was 26.6% (17.5, 5.4 and 12.1% in healthy blood donor (control), respectively). Because the patient had large numbers of CD4-CD8- cells in the PBL, CD4-CD8- LAK were generated from them. The CD4-CD8- LAK cells exhibited extremely high killer activity, whereas the CD8+ LAK cells generated from the CD8+ cells showed a low level of killer activity. These results suggest that the tumor-free condition of this patient may be related to these high killer activities. In this patient, several cytokines were also determined, although the results were not completely interpreted.

CD8-Positive T-Lymphocytes↗

The functional limitations of tetraplegic hands for intermittent clean self-catheterisation.

Since the introduction of intermittent self-catheterisation by Lapides et al, low pressure voiding methods have been adopted actively in our centre. A retrospective review of 47 patients with cervical spinal cord injury (CSCI) who performed independent (self) clean intermittent catheterisation (CIC) on discharge is presented. Their functional abilities were evaluated by both the Frankel and the Zancolli scales. Fourteen out of the 47 patients could manage independent CIC, 17 assisted CIC, nine tapped or voided voluntarily, two were discharged with a diaper, one with a suprapubic catheter, and four with an indwelling catheter. According to Frankel's classification, four patients were in A category, four in B, one in C and five in D among the group of complete CIC. C6A/C5B (right/left hand) by Zancolli's classification was the highest level of ability for all these 14 patients; and one patient (a 30-year-old male, Frankel B classification) could manage independent CIC with the aid of our special device. However, the practical limit of functional hands for independent CIC appeared to be about C6B1.

Adolescent↗

Antegrade and retrograde fluid transport through the vas deferens.

Intraluminal pressure of the seminal tract at seminal emission from the ejaculatory duct and the mode of transport of cauda epididymal contents were investigated to explore the mechanism of sperm transport. Direct electrical stimulation of any site of the cauda epididymis and vas deferens, which generated nerve-transmitted muscle contraction, caused elevation of the intraluminal pressure only at the cauda epididymis, whereas stimulation of the testis, caput, and corpus epididymis caused no response. The dye instilled in the cauda was emitted into the urethra during the stimulation. Shortly after discontinuation of the stimulation, retrograde movement of residual dye in the vas resulted in its ultimate reentry into the cauda epididymis. Significant decrease of the muscle tonus just after contraction was observed at the cauda. Distension of the wall of the vas generated elevation of the intraluminal pressure only at the site distended. The above results indicate the presence of rapid antegrade and retrograde movement of the sperm and the crucial role of the cauda epididymis on the sperm transport.

Animals↗

Relationship of the structure of ureteral muscularis to in vitro spontaneous contractions.

We investigated the anatomical structure of the smooth muscle layers of the mid portion of the canine ureter. In transverse sections the inner muscle bundles appear to be oriented longitudinally and the outer muscle bundles appear to be oriented in a circular configuration. In sections cut parallel with the longitudinal axis of the ureter, the inner and outer bundles appear to be oblique and are oriented in a mesh-line manner. In oblique sections, cut parallel with the helically oriented ureteral muscle, bundles appear to be oriented in a lengthwise configuration. These anatomical studies show that canine ureteral smooth muscle is composed of spiral fibers in a mesh structure and that helical muscle strips which include a significant percentage of continuous bundles have a greater capacity to generate spontaneous contractions in vitro than do transverse and longitudinal muscle strips.

Animals↗

Effects of clenbuterol on rabbit vesicourethral muscle contractility.

Clenbuterol (10(-10)-10(-7) M), a selective beta 2-adrenoceptor agonist, reduced spontaneous contractile force of isolated rabbit bladder dome, bladder base and proximal urethra. Clenbuterol inhibited both acetylcholine (Ach)-and electrical field stimulation (EFS)-induced contractions of rabbit bladder dome, but was more potent in inhibiting EFS-than Ach-induced contractions. Acetylcholine-but not EFS-induced contractions in the bladder dome were completely inhibited by pretreatment with 10(-6) M atropine. The atropine resistant component of the EFS-induced contractions was completely inhibited by tetrodotoxin, 10(-6) M. Clenbuterol and a non-selective beta-adrenoceptor agonist, isoproterenol, potentiated the EFS-induced contractions of isolated striated muscle preparations from the external urethral sphincter and from the extensor digitorum longus in the rabbit. Clenbuterol was more potent than isoproterenol in increasing EFS-induced contractile force in the external urethral sphincter, whereas isoproterenol was more potent than clenbuterol in increasing EFS-induced contractile force in the extensor digitorum longus. These data suggest that clenbuterol may have a role in the treatment of urinary incontinence by inhibiting the detrusor contraction and fascilitating the external urethral sphincter selectively.

Acetylcholine↗

[Natural killer (NK) and lymphokine-activated killer (LAK) activities of a patient recovered from bladder cancer, and the characteristics of LAK cells generated from lymphocyte subsets].

NK and LAK activities of a patient who recovered from bladder transitional cell carcinoma were determined. He was diagnosed in 1980 and operations, radiations and chemotherapies were repeated until 1986. Since 1987, a relapse has not been recognized, and he is now in a tumor free state. Recently, his very high NK and LAK activities were found. The percentage of CD 16+ in his peripheral blood lymphocytes (PBL) was 52.9%, the CD 4- CD 8- CD 16+ was 26.6% (17.5% and 12.1% in control, respectively). It seems likely that his tumor free condition may be related to these high killer activities. As a high number of CD 4- CD 8- cells were included in his PBL, it was possible to generate a CD 4- CD 8(-)-LAK and compare it with the CD 8(+)-LAK. The CD 4- CD 8(-)-LAK exhibited higher killer activity which was maintained for a long period of the culture, and a strong adherence property against the cultured tumor cells. Whereas, the CD 8(+)-LAK did not show such a high level of killer activity which decreased after two weeks into the culture. However, the CD 8(+)-LAK in this patient demonstrated higher killer activity against the auto-tumor cell line compared to what occurred with the control. A type of specific killing against auto-tumor cells may be contained in his CD 8(+)-LAK, although the MHC-restrictive killing was not confirmed. It remains unclear why the killer activities increased in this patient.

CD4 Antigens↗

[The experimental evaluation of the difference in closing dynamics of internal urethral ostium on the urinary continence and on the ejaculation induced by an administration of phenylephrine].

BACKGROUND: The internal urethral ostium is usually closed both on the ejaculation and on the urine collection, although the difference of the closing characteristics have not been known. METHODS: The difference in closing style of bladder neck (internal urethral ostium) between on the phenylephrine administration corresponding state to the ejaculation and on the filling of urinary bladder corresponding state to the urinary continence was evaluated by Stereo-UPP method using mongrel dogs. RESULTS: On phenylephrine administration, the length between verumontanum and bladder neck was lengthened, and a remarkable pressure increase was observed in the area. On the urinary continence filling physiological saline in the bladder, the length of the urethra on the UPP curve of the anterior wall of urethra was lengthened (10%) and the base of bladder was gradually become flat. The pressure in the bladder neck was not relatively increased. CONCLUSIONS: The internal urethral ostium was closed both on the phenylephrine administration and on the urine collection, although the closing characteristics of each was very different. It was demonstrated that on the phenylephrine administration the area between the verumontanum and the bladder neck was lengthened, together with the rise of pressure in the area, whereas on the urine collection bladder neck was closed in low pressure by flattening the base of bladder.

Adrenergic alpha-Agonists↗

[A clinico-pathological study of renal cell carcinoma with a diameter of less than 5 cm].

To examine the indication of nephron sparing operations, we searched 31 nephrectomized kidneys with renal cell carcinoma for small associated lesions in the normal-appearing portion of these kidneys. The diameter of the predominant tumors was between 15 and 50 mm. The kidneys were serially sectioned at 5-mm intervals, and all sections were examined microscopically. Two of the 31 kidneys had a small renal cell carcinoma, and four had a small adenoma in the normal-appearing portion. We recommend that the nephron-sparing operation should be is performed limitedly and that radical nephrectomy is yet a standard operation in the presence of a normal contralateral kidney.

Adenoma↗

Function and distribution of autonomic receptors in canine ureteral smooth muscle.

There have been only a few reports of the measurement of autonomic receptors in ureteral smooth muscle. Furthermore, it is so difficult to maintain stable spontaneous contractions in the ureter, that either electrical field stimulation or KCl at high concentrations are utilized to induce ureteral contractions in many in vitro ureteral pharmacologic examinations. We used the spiral ureteral strips which generate spontaneous contractions in the ureter in present experiments. Norepinephrine, phenylephrine, clonidine, carbachol, and prostaglandin F2 alpha enhanced the spontaneous contractile force and/or increased the contractile frequency of spontaneous rhythmic contractions in spirally-incised muscle strips from isolated canine ureters. In contrast, isoproterenol, terbutaline, a beta 2-adrenergic agonist, and prostaglandin E2 reduced the spontaneous contractile force and/or decreased the contractile frequency of spontaneous rhythmic contractions. Dobutamine, a beta 1-adrenergic agonist, did not affect significantly the spontaneous rhythmic contractions. The effects of the prostaglandins were not influenced by autonomic antagonists or tetrodotoxin. The existence of alpha 1-, alpha 2-, and beta-adrenoceptors and muscarinic cholinergic receptors were demonstrated in the canine ureter using radioligand techniques. The density of alpha 1-receptors binding sites was significantly greater than that of the other receptors examined. Our data show that the sympathetic nervous system is more involved than the para-sympathetic nervous system in canine ureteral contractile activities, and that alpha- and beta-receptors contained in canine ureteral smooth muscle are comprised mainly of the alpha 1- and beta 2-subtypes. It is also suggested that prostaglandins directly affect canine ureteral contraction.

Animals↗

Carrier detection of Werner's syndrome using a microsatellite that exhibits linkage disequilibrium with the Werner's syndrome locus.

Werner's syndrome (WS) is a rare autosomal recessive disorder, one of the progeroid syndromes, characterized by features of premature aging. The genetic defect in WS is unknown but recently the genetic linkage of WS to several markers on the short arm of chromosome 8 has been reported. Genetic analysis of 25 families with WS demonstrated that D8S339 was the closest marker linked to the gene locus for Werner's syndrome (WRN), with a peak lod score of 18.29 at recombination frequency 0.001, and showed a linkage disequilibrium with the WRN locus. We studied two unrelated families with WS using ANK1, D8S339, and D8S360. The mutative haplotype identified through the generations in pedigrees provides a means of carrier detection and presymptomatic diagnosis.

Female↗