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Shingo Takada

Publications and source records attributed to Shingo Takada.

11 recordsLinked to original sources
PubMed2006

Isolation of germ cells from leukemia and lymphoma cells in a human in vitro model: potential clinical application for restoring human fertility after anticancer therapy.

More than 70% of patients survive childhood cancer, but chemotherapy and radiation therapy may cause irreversible impairment of spermatogenesis. To treat infertility secondary to anticancer treatment for childhood cancer, we have developed a procedure to isolate germ cells from leukemic mice by fluorescence-activated cell sorting with two surface markers, and transplantation of isolated germ cells successfully restored fertility without inducing leukemia. In the present study, we analyzed human germ cells and human malignant cells, including five leukemia cell lines and three lymphoma cell lines, by fluorescence-activated cell sorting with antibodies against MHC class I and CD45. Testicular specimens were obtained from a patient who underwent surgery for testicular rupture. In the high forward scatter and low side scatter region, no malignant cells were found in the MHC class I-negative and CD45-negative fraction (the germ cell fraction), with the exception of K562 cells. A total of 39.2% of the germ cells were found in the germ cell fraction. A total of 1.45% of K562 cells were found in the germ cell fraction. Treatment with IFNgamma induced the expression of MHC class I on K562 cells but not on germ cells and made it possible to isolate germ cells from K562 cells. In conclusion, we isolated human germ cells from malignant cells with two surface markers after treatment with IFNgamma. Immunophenotyping for each patient will be necessary before isolation and induction of surface marker will be clinically applicable.

Cell Line, Tumor↗
PubMed2006

Salvage microdissection testicular sperm extraction after failed conventional testicular sperm extraction in patients with nonobstructive azoospermia.

PURPOSE: TESE is considered the best procedure for identifying a tubule for spermatozoa retrieval. This technique improves the SRR to around 50%. However, it has been unclear whether it is useful in patients in whom conventional TESE has failed. We compared the outcome of microdissection TESE in patients in whom conventional TESE failed to that in patients who did not undergo conventional TESE. We also evaluated relations between the outcome of salvage microdissection TESE and the characteristics of previous conventional TESE. MATERIALS AND METHODS: A total of 46 patients with nonobstructive azoospermia in whom salvage microdissection TESE was performed after failed conventional TESE were included. Patient characteristics and the SRR were compared between these patients and 134 in whom conventional TESE had not been performed previously. The previous TESE procedure, testicular histology and interval between TESEs were also evaluated. RESULTS: Patient characteristics did not differ significantly between the groups. The microdissection TESE SRR also did not differ significantly between the groups (45.7% vs 44.0%). The possibility of successful spermatozoa retrieval by salvage microdissection TESE remained regardless of the previous failure of any other TESE procedure and regardless of testicular histology. The salvage microdissection TESE SRR was not related to the interval between TESEs. CONCLUSIONS: Because salvage microdissection TESE is effective in patients in whom conventional TESE has failed, this option should be made available to them with the understanding that extended followup after salvage microdissection TESE is necessary due to the risk of hypogonadism.

Adult↗
PubMed2006

Associations of homologous RNA-binding motif gene on the X chromosome (RBMX) and its like sequence on chromosome 9 (RBMXL9) with non-obstructive azoospermia.

AIM: To investigate the associations of autosomal and X-chromosome homologs of the RNA-binding-motif (RNA-binding-motif on the Y chromosome, RBMY) gene with non-obstructive azoospermia (NOA), as genetic factors for NOA may map to chromosomes other than the Y chromosome. METHODS: Genomic DNA was extracted using a salting-out procedure after treatment of peripheral blood leukocytes with proteinase K from Japanese patients with NOA (n=67) and normal fertile volunteers (n=105). The DNA were analyzed for RBMX by expressed sequence tag (EST) deletion and for the like sequence on chromosome 9 (RBMXL9) by microsatellite polymorphism. RESULTS: We examined six ESTs in and around RBMX and found a deletion of SHGC31764 in one patient with NOA and a deletion of DXS7491 in one other patient with NOA. No deletions were detected in control subjects. The association study with nine microsatellite markers near RBMXL9 revealed that D9S319 was less prevalent in patients than in control subjects, whereas D9S1853 was detected more frequently in patients than that in control subjects. CONCLUSION: We provide evidence that deletions in or around RBMX may be involved in NOA. In addition, analyses of markers in the vicinity of RBMXL9 on chromosome 9 suggest the possibility that variants of this gene may be associated with NOA. Although further studies are necessary, this is the first report of the association between RBMX and RBMXL9 with NOA.

Adult↗
PubMed2005

Transplantation of spermatogonial stem cells isolated from leukemic mice restores fertility without inducing leukemia.

More than 70% of patients survive childhood leukemia, but chemotherapy and radiation therapy cause irreversible impairment of spermatogenesis. Although autotransplantation of germ cells holds promise for restoring fertility, contamination by leukemic cells may induce relapse. In this study, we isolated germ cells from leukemic mice by FACS sorting. The cell population in the high forward-scatter and low side-scatter regions of dissociated testicular cells from leukemic mice were analyzed by staining for MHC class I heavy chain (H-2K/H-2D) and for CD45. Cells that did not stain positively for H-2K/H-2D and CD45 were sorted as the germ cell-enriched fraction. The sorted germ cell-enriched fractions were transplanted into the testes of recipient mice exposed to alkylating agents. Transplanted germ cells colonized, and recipient mice survived. Normal progeny were produced by intracytoplasmic injection of sperm obtained from recipient testes. When unsorted germ cells from leukemic mice were transplanted into recipient testes, all recipient mice developed leukemia. The successful birth of offspring from recipient mice without transmission of leukemia to the recipients indicates the potential of autotransplantation of germ cells sorted by FACS to treat infertility secondary to anticancer treatment for childhood leukemia.

Animals↗
PubMed2005

Outcome of gonadotropin therapy for male hypogonadotropic hypogonadism at university affiliated male infertility centers: a 30-year retrospective study.

PURPOSE: Hypogonadotropic hypogonadism (HH) is an uncommon cause of male infertility. Even specialized centers see small numbers of patients and have little experience in restoring fertility in these patients. To explore the phenotypic heterogeneity and treatment outcome of HH, we summarized our 30-year experience. MATERIALS AND METHODS: Medical charts of 36 male patients (age range 11 to 42 years) with HH (81% primary, 19% secondary) treated at university affiliated male infertility centers were reviewed. Pubic hair stage, genital stage, testicular volume (TV), sexual function and sperm production were determined before and after human chorionic gonadotropin/human menopausal gonadotropin (hCG/hMG) treatment. Differences were analyzed statistically. RESULTS: The population was stratified according to initial TV into a small testis subset (TV less than 4 ml in 23) and a large testis subset (TV 4 ml or greater in 13). Comparison of these 2 subsets revealed significant differences in the incidence of cryptorchidism (39% vs 8%) and Kallmann's syndrome (22% vs 0%), pubic hair stage (1.3 +/- 0.5 vs 3.5 +/- 1.4), genital stage (1.2 +/- 0.4 vs 3.9 +/- 0.9) and TV (1.6 +/- 0.9 vs 7.5 +/- 3.5 ml). Long-term administration of hCG/hMG for 12 to 240 months (average 56 +/- 11) resulted in sperm production in only 36% of the small testis subjects but in 71% of the large testis subjects. CONCLUSIONS: Initial TV values provide insight into phenotypic variables such as time of onset and severity in patients with primary or secondary HH, and may predict sperm output in response to hCG/hMG therapy.

Adolescent↗
PubMed2003

[Urethral stent (Memotherm) for the treatment of benign prostatic hyperplasia].

We used a urethral stent for management of high-age and high-risk patients with benign prostatic hyperplasia (BPH) who needed surgical therapy. Nine patients were treated by this method. Chief complaints were urinary retention in 6 patients, dysuria with much residual urine in 2 and dysuria in 1. Blood loss and complications of the method were minimal. Postoperatively, 8 of the patients were able to void and on the average, residual urine of the patients was approximately 10 ml. Implantation of the urethral stent is a safe and non-invasive therapy for the patients who are unsuitable for invasive therapy.

Aged↗
PubMed2003

[Squamous cell carcinoma of the renal pelvis with giant hydronephrosis].

We report a case of squamous cell carcinoma of renal pelvis associated with giant hydronephrosis. A 71-year-old woman presented to our hospital with a complaint of abdominal fullness due to the right giant hydronephrosis. Although the diagnosis of her hydronephrosis was made about 20 years ago at another hospital, it had been left untreated. Computed tomography showed the right hydronephrosis of 20 x 20 x 25 cm in diameter and no evidence of tumor or calculus in the right urinary tract. For relief of her complaint, right nephrectomy was performed. The fluid content was bloody and 4,200 ml in volume. Histological examination revealed a flat type squamous cell carcinoma of the renal pelvis. This is the 30th case of renal pelvic malignant tumor associated with giant hydronephrosis reported in Japan. The literature was reviewed and the management of giant hydronephrosis was discussed.

Aged↗
PubMed2002

[48XXYY Klinefelter's syndrome with recurrent foot ulcers: a case report].

A case of 48XXYY Klinefelter's syndrome diagnosed with foot ulcers, in a 43-year-old man, is reported. He presented to the Department of Dermatology in our hospital with the chief complaint of recurrent foot ulcers. He was referred to us because of atrophic external genitalia. The present condition and endocrinological examination suggested Klinefelter's syndrome. Chromosomal analysis revealed that his chromosomal type is 48XXYY. This is the 24th case of Klinefelter's syndrome with 48XXYY chromosome and is the 5th case associated with foot ulcers in Japan. Here we report this case together with a brief review of the previously reported cases.

Foot Ulcer↗
PubMed2002

[Sarcomatoid carcinoma of the urinary bladder: a case report].

A 63-year-old man was admitted to our hospital for a bladder tumor. Drip infusion pyelography, computerized tomography (CT) and magnetic resonance imaging suggested the presence of a large invasive tumor in the right wall of the bladder. Histopathological findings by transurethral resection of bladder tumor showed the presence of sarcomatous and carcinomatous elements. Immunohistochemical examination showed that the sarcomatous component did not stain for S-100 protein or for smooth muscle actin but it stained for epithelial markers. Under the diagnosis of sarcomatoid carcinoma, we performed a total cystectomy and ileal conduit without chemotherapy or radiation. A follow-up CT taken at four months postoperatively showed no evidence of recurrence.

Carcinosarcoma↗