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Biomedical subjects

T Umekawa

Publications and source records attributed to T Umekawa.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Endopyelotomy with ureteral cutting balloon device: long-term follow up of 13 patients].

BACKGROUND: This study investigated the feasibility and long term results of retrograde endopyelotomy with the Acucise ureteral cutting balloon device in the management of ureteropelvic junction (UPJ) obstruction. METHODS: Thirteen patients (primary: 12, secondary: 1, male: 7, female: 6, mean age: 36) with UPJ obstruction were treated by the Acucise under fluoroscopic guidance. After cutting the stenotic area electrically using cutting wire and dilatation by the balloon, ureteral catheter (7-14 Fr) was inserted for 6-8 weeks. RESULTS: The mean operative time was 43 minutes, the median postoperative hospital stay was 4 days. The subjective success rate (disappearance of the abdominal pain) was 92% (11/12) and the objective success rate evaluated by radiographic studies was 62% (8/13). One patient needed a transfusion but no other major complication occurred in the treatment. The failure 5 patients were now under conservative follow up. CONCLUSION: Our limited data suggest that endopyelotomy with the Acucise device offer lower morbidity with slightly lower success rate compared other endopyelotomies. We believe that Acucise endopyelotomy can be an appropriate one of the first-line therapy for UPJO.

Adult↗
PubMed1998

beta 3-Adrenergic agonist induces a functionally active uncoupling protein in fat and slow-twitch muscle fibers.

The mitochondrial uncoupling protein (UCP) has usually been found only in brown adipose tissue. We recently observed that a chronic administration of the beta 3-adrenergic agonist CL-316,243 (CL) induced the ectopic expression of UCP in white fat and skeletal muscle in genetic obese yellow KK mice. The aim of the present study was to examine whether UCP could be induced in nongenetic obese animals produced by neonatal injections of monosodium L-glutamate (MSG). The daily subcutaneous injection of CL (0.1 mg/kg) to MSG-induced obese mice for 2 wk caused significant reductions of body weight (15%) and white fat pad weight (58%). Northern and Western blot analyses showed that CL induced significant expressions of UCP in the white fat and muscle, as well as in brown fat. Immunohistochemical observations revealed that the UCP stains in white fat were localized on multilocular cells and that those in muscle were localized on slow-twitch fibers rich in mitochondria. Immunoelectron microscopy confirmed the mitochondrial localization of UCP in the myocytes. The guanosine 5'-diphosphate (GDP) binding to mitochondria in brown fat doubled after the CL treatment. Moreover, significant GDP binding was detected in the white fat and muscle of the CL-treated mice, at about one-fourth and one-thirteenth the activity of brown fat, respectively, suggesting that ectopically expressed UCP is functionally active. We concluded that the beta 3-adrenergic agonist CL can induce functionally active UCP in white fat and slow-twitch muscle fibers of obese mice.

Adipose Tissue↗
PubMed1998

Anti-glomerular basement membrane nephritis after extracorporeal shock wave lithotripsy.

Rapidly progressive glomerulonephritis was observed in a 37-year-old woman following the administration of extracorporeal shock wave lithotripsy (ESWL) for a single stone in her right kidney. The renal biopsy specimen showed diffuse cellular crescents in all glomeruli, with linear deposits of immunoglobulin G and complement component C3 along the glomerular basement membrane (GBM). Circulating anti-GBM antibodies were detected by enzyme-linked immunosorbent assay. Thus, the patient was diagnosed with anti-GBM nephritis. It is suggested that ESWL produced an alteration in the GBM leading to the production of anti-GBM antibodies.

Adult↗
PubMed1998

Acute and chronic regulation of ob mRNA levels by beta3-adrenoceptor agonists in obese Yellow KK mice.

The inhibitory effect of beta3-adrenoceptor agonists on the ob gene in brown adipose tissue (BAT) and white adipose tissue (WAT) is now well documented both in vivo in lean animals and in vitro, but the reported effects of beta3-adrenoceptor agonists on ob gene expression in obese animals remain controversial. We investigated whether ob gene expression in BAT and WAT is reduced by acute and chronic administrations of a beta3-adrenoceptor agonist, CL316,243 (CL). The ob gene mRNA levels in BAT, perimetric and inguinal WAT of obese Yellow KK mice were about 4-fold higher than those of lean controls. Acute exposure (6 h) to CL decreased ob gene mRNA levels in three fat depots in both animals. Chronic exposure (10 days) to CL also decreased ob gene mRNA levels in BAT, perimetric, and inguinal WAT in both animals. We concluded that acute and chronic regulation by a beta3-adrenoceptor agonist suppressed ob gene expression in obese Yellow KK mice and lean controls.

Adipose Tissue↗
PubMed1998

[Beta 3 adrenergic receptor polymorphism and obesity].

The beta 3-adrenoceptor plays a significant role in the control of lipolysis and thermogenesis in the brown adipose tissue of rodents and humans. In human beta 3-adrenoceptor, a Trp to Arg replacement has recently been discovered. This change which occurs at position 64, in the first coding exon, has been correlated with increased weight gain, difficulty in losing weight, insulin resistance syndrome, and worsened diabetic situation. Higher percentages of this mutation are observed in Pima Indians (over 30%) and Japanese (20%). The possible functional mechanism of Trp54Arg is reported using human HEK293 cell line stably expressing the wild type and the [Arg64] beta 3-adrenoceptor type. Beta 3-adrenoceptor agonists available for humans are been also developing. In this paper we describe these points up-to-date.

Adipose Tissue↗
PubMed1998

Osteopontin antisense oligonucleotide inhibits adhesion of calcium oxalate crystals in Madin-Darby canine kidney cell.

PURPOSE: We previously suggested that osteopontin (OPN) plays an important role in the process of deposited calcium crystals adhesion to cells in the early stages of urolithiasis. To further confirm this theory, we tried to inhibit OPN expression at the translational level and examined its cellular biological consequence on the formation and adhesion process of crystals. MATERIALS AND METHODS: We synthesized antisense and sense oligonucleotide corresponding to an appropriate part of the coding sequence for OPN in Madin Darby canine kidney (MDCK) cells. With the aid of lipofection reagent DOTAP, antisense and sense oligonucleotide were introduced into MDCK cells grown in a confluent monolayer. After further incubation, inhibition of OPN expression in the cells was assessed by immunofluorescence photomicrography, and formation of calcium oxalate crystals was quantitated by incorporation of 45Ca into the stone and visualized by scanning electron microscopy (SEM). RESULTS: Antisense oligonucleotide at concentrations higher than 20 microM inhibited synthesis of OPN. Incorporation of 45Ca into the calculus stone was inhibited by the addition of oligonucleotide in a concentration dependent manner in a range above 20 microM. More than 90% of incorporation was inhibited at 50 microM as compared to control. Inhibition of calcium crystal formation was confirmed by SEM. CONCLUSIONS: OPN was shown as a major component in the extracellular matrix involving the formation and adhesion of calcium crystals in the distal renal tubular cells, suggesting that OPN plays an important role in stimulating deposition and adhesion of calculus crystals to cells in the early stages of urolithiasis.

Animals↗
PubMed1998

[Endopyelotomy with Acucise for secondary ureteropelvic junction obstruction: report of a case].

We report a case of successful endopyelotomy using the Acucise cutting balloon device for secondary ureteropelvic junction obstruction (UPJO). A 23-year-old man was hospitalized with the chief complaint of left lumbago and left hydronephrosis due to left UPJO. He underwent antegrade endopyelotomy with a nephroscope and open pyeloplasty. However, left lumbago and hydronephrosis did not show improvement. Acucise endopyelotomy was performed under epidural anesthesia. The operative time was 55 minutes and the hospital stay after the operation was 4 days. There were no operative complications and 3 months later, the operative results were satisfactory as determined by drip infusion pyelography and the disappearance of the lumbago.

Adult↗
PubMed1997

Beta 3-adrenergic-receptor polymorphism: a genetic marker for visceral fat obesity and the insulin resistance syndrome.

We investigated whether the polymorphism of the beta 3-adrenergic receptor (beta 3-AR) gene, which is associated with insulin resistance in non-diabetic subjects and an earlier onset of non-insulin-dependent diabetes mellitus in Pima Indians, was associated with visceral fat obesity and features of the insulin resistance syndrome in Japanese premenopausal obese women. There was no difference between 131 obese women and 256 control subjects (0.23 vs 0.17, p = 0.112) in the frequency of the Arg64 allele. The visceral fat area measured by computerised tomography scan was greater in homozygous Arg64Arg (172 +/- 17 cm2, n = 6) and heterozygous Trp64Arg (178 +/- 47 cm2, n = 48) women than in women homozygous for the Trp64Trp (121 +/- 46 cm2, n = 77) genotype (p < 0.01). This was also reflected by increased total body fat but not by increased body mass index. The association between the Trp64 allele and visceral fat mass by multiple regression analysis, was independent of age, body mass index and total fat mass (p < 0.004). Moreover, homozygous carriers of the Arg64 allele had higher systolic blood pressure, higher fasting and post-load glucose and insulin concentrations, higher cholesterol, and triglyceride and lower HDL-cholesterol concentrations than homozygous carriers of the Trp64 allele. Some of these differences were also observed between heterozygous Trp64Arg and homozygous Trp64Trp genotypes (glucose tolerance, insulin and cholesterol concentration). We conclude that in obese women the beta 3-AR polymorphism may be used as a genetic marker for visceral fat obesity and the insulin resistance syndrome.

Adipose Tissue↗
PubMed1997

Effect of CL316,243, a highly specific beta(3)-adrenoceptor agonist, on lipolysis of epididymal, mesenteric and subcutaneous adipocytes in rats.

To clarify whether a beta(3)-adrenoceptor agonist is more lipolytic in the visceral adipocytes than in the subcutaneous adipocytes, the lipolysis induced by CL316,243, a highly specific beta(3)-adrenoceptor agonist (relative selectivities of 0, 1 and 10,000 for beta(1)-, beta(2)- and beta(3)-receptors, respectively) was investigated in adipose tissue from rats. White adipocytes were prepared from the subcutaneous, mesenteric, and epididymal white adipose tissues of male Wistar rats (weighing about 150 g). Our findings showed that lipolysis of white adipocytes was stimulated both by the non-specific beta-adrenoceptor agonist, isoproterenol, and by the beta(3)-specific adrenoceptor agonist, CL316,243, but the lipolytic sensitivity to CL316,243 was about 10 times greater than that to isoproterenol in these three adipose tissues. Both isoproterenol and CL316,243 induced more noticeable lipolysis in the epididymal and mesenteric than in the subcutaneous adipose cells in terms of the pD2 value [-log mol l-1 for EC50 (the concentration of an agonist giving half of its own maximum stimulation)]. These findings show that CL316,243 is more lipolytic in the visceral adipose cells than in the subcutaneous adipose cells, although epididymal adipose cells showed a high lipolytic response close to those observed in visceral adipose cells. CL316,243 may therefore be especially useful for the treatment of visceral fat type obesity related to various diseases.

Adipocytes↗
PubMed1997

Octreotide and bromocriptine suppress thyroid hormone levels and thyroid nodule in an acromegalic patient with nontoxic autonomous goiter.

An acromegalic patient with nontoxic autonomous goiter was sequentially treated with octreotide and bromocriptine. Before therapy, serum GH, PRL and insulin-like growth factor-I (IGF-I) levels were increased. Free T3 and free T4 were within the normal range with suppressed TSH levels, whereas 123Iodine-uptake of thyroid was 5.6% after 24 h. During treatment with octreotide and bromocriptine, serum GH, PRL, and IGF-I became normal and free T3 and free T4 were slightly but significantly decreased, but TSH levels remained very low. After thyroidectomy, thyroglobulin, free T3 and free T4 were further decreased, and the TSH levels were recovered to normal. These findings suggested that octreotide and bromocriptine inhibit the release of thyroid hormones from the autonomous thyroid gland directly or indirectly through the decline in IGF-I.

Acromegaly↗
PubMed1997

Anti-obesity and anti-diabetic effects of CL316,243, a highly specific beta 3-adrenoceptor agonist, in Otsuka Long-Evans Tokushima Fatty rats: induction of uncoupling protein and activation of glucose transporter 4 in white fat.

The anti-obesity and anti-diabetic effects of a highly specific beta 3-adrenoceptor agonist, CL316,243 (CL; beta 1: beta 2: beta 3 = 0:1:100,000), were investigated in Otsuka Long-Evans Tokushima Fatty (fatty) and Long-Evans Tokushima Otsuka (control) rats. Daily injection of CL (0.1 mg/kg, s.c.) to these rats (10 weeks old) for 14 weeks caused a significant reduction in body weight (fatty, 27%; control, 15%), associated with a marked decrease in fat pad weight (inguinal: fatty, 60%; control, 36%; retroperitoneal: fatty, 75%; control, 77%) without affecting food intake. The levels of uncoupling protein mRNA and protein levels of uncoupling protein (UCP), as well as guanosine 5'-diphosphate-binding (a reliable index of thermogenesis) in brown adipose tissue, were lower in the fatty than in the control rats. However, after CL treatment, these parameters in brown adipose tissue increased significantly 2- to 3-fold in both groups. Furthermore, uncoupling protein was induced in white adipose tissue as well as in brown adipose tissue. The fatty rats showed hyperglycemia and hyperinsulinemia during the glucose tolerance test, but CL ameliorated these parameters. These findings suggest that decreased thermogenesis in brown adipose tissue may be one of the causes of obesity in the fatty rats and that administration of CL prevents obesity by decreasing white fat mass, by activating brown adipose tissue thermogenesis, and by inducing uncoupling protein in white adipose tissue. Furthermore, CL treatment may inhibit diabetes mellitus by ameliorating obesity and by activating glucose transporter 4 in white adipose tissue and brown adipose tissue.

Adipose Tissue↗
PubMed1997

Effects of Trp64Arg mutation in the beta 3-adrenergic receptor gene on weight loss, body fat distribution, glycemic control, and insulin resistance in obese type 2 diabetic patients.

OBJECTIVE: To investigate the effects of Trp64Arg mutation in the beta 3-adrenergic receptor gene on weight loss, body fat distribution, glycemic control, and insulin resistance in obese type 2 diabetic patients. RESEARCH DESIGN AND METHODS: We measured body weight, waist-to-hip ratio (WHR), adjusted resting metabolic rate, fasting blood glucose, fasting serum insulin levels, insulin resistance index (fasting glucose x fasting insulin/22.5), and HbA1c levels before and after 12 weeks of obesity treatment in 61 obese women with type 2 diabetes. The MvaI polymorphism of the beta 3-adrenergic receptor gene was determined by polymerase chain reaction-restriction fragment length polymorphism analysis. RESULTS: Of obese type 2 diabetic patients, those with the mutation (n = 24) had a higher WHR (P < 0.001), a lower adjusted metabolic rate, and higher blood glucose levels, serum insulin levels, insulin resistance index (P < 0.001), and HbA1c levels (P = 0.016). Furthermore, patients with the mutation had smaller decreases in body weight, WHR, insulin resistance index, and HbA1c levels after the weight-loss program compared with patients without the mutation (n = 37), even though food intake, exercise, and serum thyroid hormone levels were similar in both groups. CONCLUSIONS: These present findings show that the Trp64Arg allele of the beta 3-adrenergic receptor gene may predict difficulty in losing body weight, lowering WHR, and improving glycemic control and insulin resistance in obese patients with type 2 diabetes.

Adult↗
PubMed1997

Beta 3-adrenoreceptor gene polymorphism: a newly identified risk factor for proliferative retinopathy in NIDDM patients.

Proliferative diabetic retinopathy is an important cause of visual impairment. We investigated whether the polymorphism of the beta 3-adrenoreceptor (beta 3-AR) gene, which is associated with insulin resistance and an earlier onset of NIDDM, was associated with proliferative diabetic retinopathy (PDR) in 215 Japanese NIDDM patients with a duration of diabetes of > or = 10 years. The polymorphism of the beta 3-AR gene was determined by polymerase chain reaction-restriction fragment length polymorphism analysis. The Trp64Arg allele of the beta 3-AR gene was significantly more frequent in the NIDDM patients with PDR (P = 0.002), but not in those with non-PDR (P = 0.151), than in NIDDM patients without diabetic retinopathy. Those with the mutation had an earlier onset of diabetes, a longer duration of diabetes, and higher current and maximal BMI values, compared with those without the mutation. Moreover, this mutation was also associated with higher serum triglyceride and decreased HDL-cholesterol levels. When adjustment was made for age, age at diagnosis, duration of diabetes, current BMI, systolic blood pressure, HbA1e, and serum lipids in a multiple regression analysis, a significant association was found between the Trp64Arg allele and diabetic retinopathy (P = 0.039). The Arg/Arg or Arg/Trp genotype was significantly associated with PDR, compared with the Trp/Trp genotype, with an odds ratio of 2.55 (95% CI 1.25-5.16). We concluded that the beta 3-AR gene polymorphism is a newly identified risk factor for PDR.

Aged↗
PubMed1997

[Endopyelotomy with the ureteral cutting balloon device for ureteropelvic junction obstruction].

BACKGROUND: This study investigated the feasibility of retrograde endopyelotomy with the Acucise ureteral cutting balloon device in the management of ureteropelvic junction (UPJ) obstruction. METHODS: Six patients (male: 3, female: 3, age: 6-18) with UPJ obstruction and abdominal pain as the chief complaint, were treated by the Acucise ureteral cutting balloon device (flexible ureteral catheter, 7 Fr) under epidural or general anesthesia (for the 6-year-old girl only). After cutting the stenotic area electrically and posteriolaterally using a 3 cm cutting wire and dilation by the balloon to a maximum of 24 Fr for 10 seconds, a 6/10 Fr (for children) or 7/14 Fr (for adults) endopyelotomy ureteral catheter was left in situ for 8 weeks after the operation. After removing the ureteral catheter transurethrally, the results, including the patency of the UPJ, of this procedure were evaluated by intravenous pyelography and the disappearance of the chief complaint, abdominal pain, 12 weeks after removing the ureteral catheter. RESULTS: Mean operative time was 47 (25-90) minutes and the hospital stay after the operation was 5.3 (3-14, median: 4) days. There was no transfusion or emergent open operation for uncontrolled bleeding in this series. The results 20 months after the operation: improvement of hydronephrosis was shown in 4 patients (66.7%) on intravenous pyelography and abdominal pain disappeared in all patients. CONCLUSION: UPJ obstruction may be easily and safely treated by retrograde endopyelotomy with the Acucise ureteral cutting balloon device. The principal potential advantage of this procedure is reduced morbidity compared to that with antegrade or retrograde endopyelotomy by endoscopy.

Adolescent↗
PubMed1997

[Sialic acid determinations of serum and urine specimens in calcium-containing urinary stone formers].

PURPOSE: The aim of the present study was to compare sialic acid concentrations of serum and urine specimens in both calcium (Ca)-containing urinary stone formers and non-stone formers. Moreover, we studied inhibitory activity of sialic acid upon the calcium oxalate (CaOx) crystal aggregation and growth. MATERIALS AND METHODS: Sialic acid determinations were done on fresh serum and urine samples of 35 Ca-containing urinary stone formers (stone formers group) and 20 non-stone formers (patient controls group). Inhibitory activity of sialic acid upon the CaOx crystal aggregation and growth was studied by using in vitro assay method of seed crystal system. RESULTS: Serum sialic acid concentrations were found to be similar in the two groups. Urinary sialic acid concentrations were significantly lower in the urine specimens of stone formers than in their patient controls. Sialic acid showed a dose dependent inhibitory activity upon the CaOx crystal aggregation and growth into seed crystal method. CONCLUSION: It is suggested that urinary sialic acid may play some role during the phase of stone formation from the results of the present study, because sialic acid shows marked inhibitory activity upon the CaOx crystal aggregation and growth at concentrations higher than 100 mg/dl.

Aged↗