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Kenjiro Kohri

Publications and source records attributed to Kenjiro Kohri.

At least 19 recordsLinked to original sources
PubMed2007

Laparoscopic management for urachal cyst in a 9-year-old boy.

We report a boy with urachal cyst managed laparoscopically. A 9-year-old boy was referred from another hospital with a history of low abdominal pain. We laparoscopically excised the urachal cyst, removing all structures within the umbilicovesical fascia, including the urachus and each medial umbilical ligament, as well as the associated peritoneum from the umbilicus to the bladder dome. Laparoscopic management of urachal disease can be performed safely, with minimal postoperative pain, excellent cosmetic results and early ambulation. We advocate the use of laparoscopic treatment of urachal anomalies in children.

Child↗
PubMed2007

Validation study of the prediction system for clinical response of M-VAC neoadjuvant chemotherapy.

To predict the efficacy of the M-VAC neoadjuvant chemotherapy for invasive bladder cancers, we previously established the method to calculate the prediction score on the basis of expression profiles of 14 predictive genes. This scoring system had clearly distinguished the responder group from the non-responder group. To further validate the clinical significance of the system, we applied it to 22 additional cases of bladder cancer patients and found that the scoring system correctly predicted clinical response for 19 of the 22 test cases. The group of patients with positive predictive scores had significantly longer survival than that with negative scores. When we compared our results with a previous report describing the prognosis of the patients with cystectomy alone, the results imply that patients with positive scores are likely to benefit from M-VAC neoadjuvant chemotherapy, but that the chemotherapy would shorten the lives of patients with negative scores. We are confident that our prediction system to M-VAC therapy should provide opportunities for achieving better prognosis and improving the quality of life of patients. Taken together, our data suggest that the goal of 'personalized medicine', prescribing the appropriate treatment regimen for each patient, may be achievable by selecting specific sets of genes for their predictive values according to the approach shown here.

Aged↗
PubMed2007

Testicular seminoma occurring 8 years after treatment of a metastatic extragonadal germ cell tumor.

A 30-year-old man was admitted with a chief complaint of left-sided scrotal enlargement, and was diagnosed as having testicular seminoma after orchiectomy. Eight years earlier, he had been treated with chemotherapy for an extragonadal germ cell tumor, without orchiectomy, leading to complete remission. His histological diagnosis at that time was a germ cell tumor, composed of choriocarcinoma and embryonal carcinoma. He was followed up without testicular biopsy. Routine pretreatment testicular biopsy in patients with extragonadal germ cell tumor is controversial, but regular long-term follow up and information on the risk of developing a metachronous testicular tumor are needed after treatment of extragonadal germ cell tumors, even when there seems to be a partial or complete clinical response.

Adult↗
PubMed2007

Influence for testicular development and histological peculiarity in the testes of flutamide-induced cryptorchid rat model.

OBJECTIVES: To investigate influence for the testicular development and to assess the usefulness as an animal model, cryptorchid rats were induced by exposure to flutamide during the fetal period and their testes examined histologically. METHODS: Flutamide was injected into the abdomen of pregnant rats for 7 days from the 14th to 20th day of gestation. The male offspring in which cryptorchidism was observed at 28 days after birth were defined as the model rats. They were divided into four groups by dosage of flutamide (2.5 mg, 5 mg, 7.5 mg, 15 mg per day), and their testicular weight, spermatogenesis (modified Johnsen score), and germ cell apoptosis were examined histochemically at 10 weeks after birth. RESULTS: The incidence of cryptorchidism including both unilateral and bilateral in the 2.5, 5, 7.5 and 15-mg flutamide groups was 58.3%, 81.9%, 93.6% and 91.0%, respectively. In the model rats, the undescended testes were located at the caudal end of the abdominal cavity, and these testes weighed less than the contra-descended testes in each group. Histologically, apoptotic cells were markedly increased, the seminiferous tubules were degenerated and disturbance of spermatid differentiation was observed in the undescended testes compared with the normal or contra-lateral descended testes. CONCLUSIONS: We found out that the incidence of undescended testes increased in a flutamide dose-dependent manner. The findings of histological examination were independent of the administrated dose of flutamide and it is suggested that exposure of the testes to abdominal temperature causes spermatogenic arrest with germ cell apoptosis. The present animal model indicates high incidence of above 90%, has no surgical stress and dose not require special techniques. We believe that the present model is a useful tool for the understanding of pathogenesis and treatment of cryptorchidism and further biological research into spermatogenesis.

Animals↗
PubMed2006

[Hypergonadism].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed2006

Complete regression of experimental prostate cancer in nude mice by repeated hyperthermia using magnetite cationic liposomes and a newly developed solenoid containing a ferrite core.

BACKGROUND: Magnetite cationic liposomes (MCLs) can be used to induce hyperthermia because they generate heat in an alternating magnetic field (AMF). This study aimed at developing more practical method for MCL hyperthermia examining the effect of MCL-induced hyperthermia on human prostate cancer in vivo. MATERIALS AND METHODS: A newly developed AMF generator incorporating a solenoid with a ferrite core (FC) was used. Human prostate cancer cells (PC-3 and LNCap) were injected subcutaneously into nude mice. MCLs were injected into tumor nodule and the mice were exposed into AMF three times at 24-hr intervals (repeated hyperthermia; RH) until complete tumor regression was observed. RESULTS: Irradiation with an AMF generated by newly developed device can adequately increase the temperature of tumor tissue. Frequent RH resulted in complete tumor regression in all nude mice. CONCLUSION: RH using MCLs may be a promising new therapy for hormone-refractory human prostate cancer in the future.

Animals↗
PubMed2006

Quantification of alpha1-adrenoceptor subtypes by real-time RT-PCR and correlation with age and prostate volume in benign prostatic hyperplasia patients.

BACKGROUND: We used a real-time reverse transcriptase polymerase chain reaction (RT-PCR) method for quantification of each alpha(1)-adrenoceptor (alpha(1)-AR) subtype expression level, and examined whether age and prostate volume influence human prostate alpha(1)-AR subtype expression. METHODS: Enrolled in our study were 75 men with lower urinary tract symptoms (LUTS) secondary to untreated benign prostatic hyperplasia (BPH). Real-time RT-PCR was performed using prostate biopsy specimens to quantify the expression level of each alpha(1)-AR subtype. RESULTS: The median expression level (interquartile range) was 1.24 (0.66-2.32), 0.16 (0.10-0.33), and 1.11 (0.75-2.27) x 1,000 copies/beta-actin for alpha(1a)-, alpha(1b)-, and alpha(1d)-AR mRNA, respectively. The expression levels differed with the individual. The expression levels of alpha(1a)-AR, alpha(1d)-AR, and total alpha(1)-AR mRNA showed a significant positive correlation with patient age, but did not correlate with prostate volume. CONCLUSION: The difference in the expression of the alpha(1)-AR subtype with the patient may be the cause of the difference in the effectiveness of several subtype-selective alpha(1)-AR antagonists from patient to patient. The increase of alpha(1)-AR mRNA expression level with age could be an important factor in the pathogenesis of clinically significant BPH.

Adrenergic alpha-Antagonists↗
PubMed2006

Genes associated with the formation of germ cells from embryonic stem cells in cultures containing different glucose concentrations.

In a previous study, we established a system for visualizing the development of germ cells from mouse embryonic stem (ES) cells in culture using knock-in ES clones in which visual reporter genes were expressed from the mouse vasa homolog, Mvh. While assessing various culture conditions, we found that germ-cell formation was markedly depressed in low glucose medium. Using a repeated polymerase chain reaction (PCR) subtraction method, we identified genes that were differentially expressed in low versus high glucose media. Three genes that were predominantly expressed in high glucose medium, thioredoxin-interacting protein (Txnip), pituitary tumor-transforming gene 1 (Pttg), and RuvB-like protein 2 (RuvBl2), were further investigated. These genes were also found to be highly expressed in adult and embryonic gonads, and RuvBl2 in particular, which encodes an ATP-dependent DNA helicase, was specifically detected in the spermatocytes and spermatids of the adult testis as well as in primordial germ cells. Furthermore, using a green fluorescent protein (GFP) fusion construct, we found that RuvBl2 was expressed in both the nucleus and cytoplasm of testicular germ cells. These findings suggest a possible relationship between glucose metabolism and germ-cell development.

ATPases Associated with Diverse Cellular Activitie↗
PubMed2006

Effects of imatinib mesylate (Glivec) as a c-kit tyrosine kinase inhibitor in the guinea-pig urinary bladder.

AIMS: In the gastrointestinal tract, slow wave activity in smooth muscle is generated by the interstitial cells of Cajal (ICC). Detrusor smooth muscle strips of most species show spontaneous contractions which are triggered by action potential bursts, however, the pacemaker mechanisms for the detrusor are still unknown. Recently, ICC-like cells have been found in guinea-pig bladder, using antibodies to the c-kit receptor. We have investigated the effects of Glivec, a c-kit tyrosine kinase inhibitor, on spontaneous action potentials in guinea-pig detrusor and intravesical pressure of isolated guinea-pig bladders. METHODS: Changes in the membrane potential were measured in guinea-pig detrusor smooth muscle using conventional microelectrode techniques. Pressure changes in the bladder were recorded using whole organ bath techniques. RESULTS: Smooth muscle cells in detrusor muscle bundles exhibited spontaneous action potentials, and spontaneous pressure rises occurred in isolated bladders. Glivec (10 microM) converted action potential bursts into continuous firing with no effects on the shape of individual action potentials. Glivec (>50 microM) reduced the amplitude of spontaneous pressure rises in the whole bladder in a dose dependent manner and abolished spontaneous action potentials in detrusor smooth muscle cells. CONCLUSIONS: The results suggest that ICC-like cells may be responsible for generating bursts of action potentials and contractions in detrusor smooth muscle. Drugs inhibiting the c-kit receptor may prove useful for treating the overactive bladder.

Animals↗
PubMed2006

Abnormal glycosylation of serum IgG in patients with IgA nephropathy.

BACKGROUND: We postulated that IgA nephropathy (IgAN) involved alterations of serum IgG. The present study was undertaken to elucidate changes in serum IgG oligosaccharide structure analysis and to assess the diagnostic usefulness of this analysis in IgAN. METHODS: The subjects were 28 children who were definitively diagnosed as having IgAN on the basis of renal biopsy and who had not received treatment for this disease; 27 healthy children; 15 untreated adults definitely diagnosed as having IgAN; 5 patients with other nephropathies; and 61 healthy adults. Oligosaccharide analyses of IgG were performed by reverse-phase high-performance liquid chromatography (HPLC) developed by Takahashi and colleagues. RESULTS: In both the children and the adults, the peak area ratio of isomers with two different galactosyl-N-acetylglucosamine (Gal-GlcNAc) binding sites was significantly lower in the presence of IgAN than in the healthy subjects (P<0.05 in children and P<0.001 in adults). The ratio of Gal-free oligosaccharides to Gal-positive oligosaccharides did not differ according to the presence or absence of IgAN in children or in adults. CONCLUSIONS: The analysis of the oligosaccharide structure of serum IgG seems to be useful in diagnosing IgAN.

Adolescent↗
PubMed2006

Expression of a fluorescent recombinant form of sperm protein phospholipase C zeta in mouse epididymal sperm by in vivo gene transfer into the testis.

OBJECTIVE: To use in vivo gene transfer into the testis by electroporation to express a fluorescent recombinant form of a testis-specific gene in the mature epididymal sperm of mice and thus study the pattern of gene localization. DESIGN: Controlled animal study. SETTING: Research laboratory at the University of Oxford. ANIMAL(S): Four- to 6-week-old male mice. INTERVENTION(S): Phospholipase C zeta (PLCzeta), the putative mammalian egg activation factor, was fused to enhanced yellow fluorescent protein (EYFP), and in vivo gene transfer by electroporation was used to introduce this transgene (PLCzeta-EYFP) into mouse testis. Transgene expression in testis and sperm were analyzed at 20 and 40 days after electroporation. MAIN OUTCOME MEASURE(S): Transgene expression in testis and epididymal sperm was analyzed by fluorescence microscopy and an excitation light source suitable for EYFP. RESULT(S): Phospholipase C zeta-EYFP was successfully expressed in epididymal sperm when analyzed 40 days after gene transfer and was localized to the head and midpiece regions. CONCLUSION(S): Our results provide the first demonstration that in vivo gene transfer can be used to study the localization of proteins in mature sperm and that this represents a powerful new technique for studying male infertility and gene function in sperm.

Animals↗
PubMed2006

Assessment of serum follicle-stimulating hormone level and testicular volume for prediction of paternity potential in pubertal boys who underwent bilateral orchiopexy in childhood.

PURPOSE: We examined infertile adults for the presence of spermatozoa in the testes, serum FSH level and testicular volume to predict paternity potential in pubertal boys who had undergone bilateral orchiopexy in childhood. MATERIALS AND METHODS: The study included 58 idiopathic infertile men (group 1), 14 infertile men who had undergone bilateral orchiopexy in childhood (group 2) and 21 pubertal boys who had undergone bilateral orchiopexy in childhood (group 3). We evaluated the correlation between FSH level and testicular volume in all groups. In groups 1 and 2 the testes were examined for the presence of spermatozoa using bilateral testicular biopsy samples. RESULTS: Judging from the presence of spermatozoa in the testes and correlation between FSH level and testicular volume, 14 patients in group 1 (24%) were categorized as being at high risk, 32 (55%) at intermediate risk and 12 (21%) at low risk for loss of paternity potential, with spermatozoa positive rates of 0%, 49% and 100%, respectively. In comparison, 4 patients in group 2 (29%) were categorized as being at high risk, 7 (50%) at intermediate risk and 3 (21%) at low risk, with spermatozoa positive rates of 0%, 43% and 100%, respectively. According to this categorization, 19% of pubertal boys in group 3 were at high risk and may already have lost their paternity potential. CONCLUSIONS: Despite bilateral orchiopexy in childhood, some male adolescents may not have the potential for paternity.

Adolescent↗
PubMed2006

Heterogeneous CPA sensitivity of spontaneous excitation in smooth muscle of the rabbit urethra.

1. To investigate the role of intracellular Ca stores in generating spontaneous excitation of the urethra, the effects of cyclopiazonic acid (CPA) on spontaneous contractions, transient increases in intracellular calcium concentration ([Ca2+]i; Ca transients) and depolarizations were examined in smooth muscles of the rabbit urethra. 2. In about 90% of circular smooth muscle (CSM) preparations, CPA (10 microM) increased the amplitude of spontaneous contractions by about 180% and reduced their frequency to some 25% of control values (CPA-resistant), while it readily abolished the contractions in the remaining preparations. 3. In about 70% of CSM preparations, CPA prevented the generation of spontaneous depolarizations termed slow waves, but increased their amplitude and duration in the remainder. CPA also prevented the generation of spontaneous Ca transients in about 40% of CSM preparations, while increasing their amplitude and duration in the remaining preparations. In CPA-resistant preparations that had been exposed to nicardipine (1 microM), subsequent CPA invariably abolished residual spontaneous depolarizations or Ca transients. CPA abolished caffeine-induced Ca transients in Ca-free solutions, suggesting that it effectively depleted intracellular Ca stores. 4. Longitudinal smooth muscles generated spontaneous action potentials, which had a shape distinct from that of slow waves in CSM. Spontaneous action potentials were abolished by nicardipine but not CPA. 5. Transmural nerve stimulation increased the frequency of Ca transients to give a sustained rise in [Ca2+]i, but inhibited their generation after blocking alpha-adrenoceptors with phentolamine (1 microM). These nerve-evoked responses were preserved in preparations that had been exposed to CPA. Similarly, both in control and CPA-treated CSM preparations, spontaneous Ca transients were accelerated by noradrenaline (NAd, 1 microM) and were suppressed by 3-morpholino-sydnonimine (SIN-1, 10 microM), a nitric oxide (NO) donor. 6. In conclusion, CSM of the urethra generates spontaneous activity, which depends on Ca release from intracellular Ca stores. However, after blocking this primary pacemaking mechanism, L-type Ca channel-dependent action potentials may drive CSM. Irrespective of the origin of pacemaking, neurally-released NAd and NO are capable of modulating spontaneous excitation.

Action Potentials↗
PubMed2006

Long-term outcome of upper urinary tract carcinoma in situ: effectiveness of nephroureterectomy versus bacillus Calmette-Guérin therapy.

BACKGROUND: We examined the long-term outcome and compared the usefulness of nephroureterectomy with that of bacillus Calmette-Guérin (BCG) therapy for the management of upper urinary tract carcinoma in situ (CIS). METHODS: We retrospectively reviewed the post-treatment course of 17 patients with CIS of the upper urinary tract who had undergone either a nephroureterectomy (group A, n = 6) or BCG therapy (group B, n = 11) at our institute. RESULTS: Median follow up was 58.3 months (range 1-120 months). Four of the six patients in group A (67%) had no recurrence and remained cystoscopically, cytologically and radiographically free of disease. The cytology became negative after an 8-week course in nine of the eleven patients in group B (82%; eight of ten units, 77%). Two of the nine patients showed recurrence after BCG therapy. One patient died of respiratory failure caused by a side-effect of BCG, which was interstitial pneumonia. There was no significant difference in either the 5-year recurrence-free survival or the 5-year cancer-specific survival between groups A and B. CONCLUSIONS: BCG therapy for CIS of the upper urinary tract is as effective as nephroureterectomy in long-term outcome, although it has some dangerous aspects. Further experience with treatment of CIS of the upper urinary tract is required.

Adjuvants, Immunologic↗
PubMed2006

Mathieu and Barcat repair with a V incision sutured meatoplasty for secondary hypospadias surgery.

AIM: Today single-stage methods are more frequently selected for hypospadias repair than multistaged methods, but complications cannot always be avoided. We employed two kinds of meatal based flip-flap urethroplasty procedures for those with an unsuccessful primary hypospadias repair. PATIENTS AND METHODS: From 1997 to 2005, a meatal based flip-flap urethroplasty was performed as a secondary hypospadias surgery on 17 patients. Basically we attempted the Mathieu repair, but when the wings of the glans were not generously widened and the urethral groove was not sufficiently deep we applied the Barcat procedure. While 11 patients were repaired with the Mathieu technique, six patients underwent the Barcat repair. The V incision sutured meatoplasty was added to obtain a natural ventral slit-like meatus. RESULTS: Ten of the 11 patients who underwent the Mathieu repair had a good outcome, but one patient developed a urethrocutaneous fistula. None of the six patients repaired with the Barcat procedure encountered postoperative complications. Cosmetically, a vertical slit was constructed near the normal neomeatus with the Mathieu and V incision sutured (MAVIS) meatoplasty and the Barcat and V incision sutured (BAVIS) meatoplasty. CONCLUSIONS: The Mathieu or the Barcat meatal based flip-flap urethroplasty procedure is feasible as a salvage surgery for those with relatively short urethral defects and adequate mobile ventral skin if an exact procedure is selected. Excellent cosmetic results could be obtained by adding the technique of V incision sutured meatoplasty.

Humans↗
PubMed2006

Role of transcription factors Ad4bp/SF-1 and DAX-1 in steroidogenesis and spermatogenesis in human testicular development and idiopathic azoospermia.

BACKGROUND: Ad4bp/SF-1 and DAX-1 are orphan members of the nuclear hormone receptor superfamily of transcription factors. In order to obtain better understandings of human testicular steroidogenesis and spermatogenesis, we examined the expression levels of both factors in human normal and idiopathic azoospermic testes and investigated their physical meaning. METHODS: First, we examined the expression level of Ad4bp/SF-1 and DAX-1 by quantitative reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry and western blotting analysis using eight normal human testicular tissues from infants to adults. Second, we performed quantitative RT-PCR using testicular biopsy samples obtained from 22 idiopathic azoospermic patients to examine the expression of Ad4bp/SF-1 and DAX-1, and analysed the correlation between the expression levels of both factors and the serum hormone levels or histological evaluation to study their potential correlation with steroidogenesis and spermatogenesis on idiopathic azoospermia. RESULTS: The expression levels of both factors in the normal testes increased with testicular development. Ad4bp/SF-1 was abundantly expressed in Leydig cell, whereas DAX-1 was expressed in Sertoli cells. The expression level of Ad4bp/SF-1 in idiopathic azoospermic patients testes positively correlated with serum testosterone (P < 0.05). The average expression levels of DAX-1 mRNA for patients with maturation arrest (0.39 +/- 0.19) and Sertoli cell-only syndrome (0.13 +/- 0.08) were lower than that with hypospermatogenesis (1.60 +/- 1.32) and normal spermatogenesis (1.30 +/- 1.41). CONCLUSION: Ad4bp/SF-1 is important for the maintenance of steroidogenesis in the human testis. DAX-1 plays a critical role in spermatogenesis in the human testis, and Sertoli cell-only syndrome and maturation arrest may result from abnormal Sertoli cell function that disrupts the normal progression of spermatogenesis.

Adolescent↗
PubMed2006

Pseudo-clitoromegaly associated with congenital prepubic sinus.

We operated on a 12-year-old girl who had clitoromegaly and a sinus on the midline prepubic area congenitally. The prepubic sinus appeared to point to the clitoris on the preoperative magnetic resonance image, but the relation between the sinus and clitoromegaly was unclear. Gray-brown discharge was emitted at the site of dissection between the prepuce and clitoris and the size of the clitoris became normal. The sinus was excised, revealing a tract 1.5 cm long that extended to the retropubic sinus, and ended in a fibrous tract that was linked to the clitoris. This suggested pseudo-hypertrophy because of the discharge collected in the end of the prepubic sinus.

Adrenal Hyperplasia, Congenital↗