Takehiko Ogawa

Yokohama City University, Yokohama, Kanagawa, Japan

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Publications (83)220.25 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: With the increasing cure rate of paediatric cancers, infertility, as one of the adverse effects of treatments, has become an important concern for patients and their families. Since semen cryopreservation is applicable only for post-pubertal patients, alternative pre-pubertal measures are necessary. Here we demonstrate that testis tissue cryopreservation is a realistic measure for preserving the fertility of an individual. Testis tissues of neonatal mice were cryopreserved either by slow freezing or by vitrification. After thawing, they were cultured on agarose gel and showed spermatogenesis up to sperm formation. Microinsemination was performed with round spermatids and sperm, leading to eight offspring in total. They grew healthily and produced progeny upon natural mating between them. This strategy, the cryopreservation of testis tissues followed by in vitro spermatogenesis, is promising to preserve the fertility of male paediatric cancer patients in the future.
    Nature Communications 01/2014; 5:4320. · 10.02 Impact Factor
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    ABSTRACT: The in vitro propagation of mouse spermatogonial stem cells (SSCs) became possible in 2003; these cultured SSCs were named germ-line stem (GS) cells. To date, however, it has not been possible to induce spermatogenesis from GS cells in vitro. Recently, we succeeded in producing functional sperm from primitive spermatogonia in explanted neonatal mouse testis tissues. Here we describe a protocol that can support spermatogenesis from GS cells up to sperm formation in vitro using an organ culture method. GS cells transplanted in the extracted testis form colonies in the tissue fragments and differentiate into sperm under the described in vitro organ culture conditions. It takes about 6 weeks to obtain sperm from GS cells. The sperm are viable, resulting in healthy offspring through micro-insemination. Thus, this protocol should be a valuable tool for the study of mammalian spermatogenesis.
    Nature Protocol 11/2013; 8(11):2098-2104. · 8.36 Impact Factor
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    ABSTRACT: Purpose: Azoospermia is a common side effect of chemotherapy. Although most patients restore spermatogenesis over time, the exact time course has not been well described. We analyzed the recovery of spermatogenesis in testicular cancer patients following chemotherapy. Patients and Methods: 49 patients, consisting of 45 treated with a bleomycin, etoposide and cisplatin (BEP) regimen and 4 with high-dose chemotherapy, were followed up with occasional semen analyses. The primary endpoint of this study was the confirmation of motile spermatozoa in the patients' semen. Results: Among 45 patients treated with BEP, 44 recovered spermatogenesis. The recovery of spermatogenesis was delayed depending on the increase in BEP cycles. In groups of patients who received 1-2, 3 and 4 cycles, the recovery rates of spermatogenesis within 2 year were 83.3, 80.0 and 66.7%, respectively. In the group with 5-6 cycles of BEP, re-spermatogenesis was significantly delayed and no patients re-established spermatogenesis within 2 years. The patients' age and semen parameters before chemotherapy were not useful as predictive factors for the recovery of spermatogenesis. Conclusion: The recovery of spermatogenesis was rather fast and was often observed as early as several months after BEP treatment when the number of cycles was <4.
    Urologia Internationalis 09/2013; · 1.07 Impact Factor
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    ABSTRACT: The trans-Golgi-network (TGN) functions as a hub organelle in the exocytosis of clathrin-coated membrane vesicles, and SMAP2 is an Arf GTPase activating protein that binds to both clathrin and the clathrin assembly protein (CALM). In the present study, SMAP2 was detected on the TGN in the pachytene spermatocyte to the round spermatid stages of spermatogenesis. Gene targeting revealed that SMAP2-deficient male mice were healthy and survived to adulthood, but were infertile and exhibited globozoospermia. In SMAP2-deficient spermatids, the diameter of proacrosomal vesicles budding from TGN increased, TGN structures were distorted, acrosome formation was severely impaired, and reorganization of the nucleus did not proceed properly. CALM functions to regulate vesicle sizes, and this study showed that CALM was not recruited to the TGN in the absence of SMAP2. Furthermore, syntaxin2, a component of the SNARE complex, was not properly concentrated at the site of acrosome formation. Thus, the present study reveals a link between SMAP2 and CALM/syntaxin2 in clathrin-coated vesicle formation from the TGN and subsequent acrosome formation. SMAP2-deficient mice provide a model for globozoospermia in humans.
    Molecular biology of the cell 07/2013; · 5.98 Impact Factor
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    ABSTRACT: It is known that cells of testis tissues in fetal or neonatal periods have the ability to reconstruct the testicular architecture even after dissociation into single cells. This ability, however, has not been demonstrated effectively in vitro. In our present study, we succeeded in reconstructing seminiferous tubules in vitro which supported spermatogenesis to meiotic phase. Testis cells of neonatal mice were dissociated enzymatically into single cells. The cells formed aggregates in suspension culture and were transferred to the surface of agarose gel to continue the culture with a gas-liquid interphase method, where a tubular architecture gradually developed during the following 2 weeks. Immunohistological examination confirmed Sertoli cells forming tubules and germ cells inside. With testis tissues of Acr-GFP transgenic mice, whose germ cells express GFP during meiosis, cell aggregates formed a tubular structure and showed GFP expressions in their reconstructed tissues. Meiotic figures were also confirmed by regular histology and immunohistochemistry. In addition, we mixed cell lines of spermagonial stem cells (GS cells) into the testis cell suspension, and found the incorporation of GS cells in the tubules in reconstructed tissues. When GS cells derived from Acr-GFP transgenic mice were used, GFP expression was observed, indicating that the spermatogenesis of GS cells was proceeding up to the meiotic phase. This in vitro reconstruction technique will be a useful method for the study of testis organogenesis and spermatogenesis.
    Biology of Reproduction 06/2013; · 4.03 Impact Factor
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    ABSTRACT: We investigated the Core Lower Urinary Tract Symptom Score as an outcome assessment tool for the treatment of lower urinary tract symptoms using silodosin. In addition, the ability of the Core Lower Urinary Tract Symptom Score to detect overactive bladder in male patients with lower urinary tract symptoms was examined. The present study included 241 males with benign prostatic hyperplasia treated at 31 medical facilities between June 2009 and December 2010. All patients were given silodosin, and the effects of silodosin intake were measured using four questionnaires: the Core Lower Urinary Tract Symptom Score, International Prostate Symptom Score, Overactive Bladder Symptom Score and Quality-of-Life index. The efficacy of silodosin for treating lower urinary tract symptoms was validated according to the total scores of all four questionnaires weighted equally (P < 0.05). Spearman's ρ among the Core Lower Urinary Tract Symptom Score, International Prostate Symptom Score and Overactive Bladder Symptom Score showed a mild-high correlation. However, the correlation between the baseline values of the Core Lower Urinary Tract Symptom Score and Quality-of-Life index was low in the groups with benign prostatic hyperplasia (ρ = 0.314) and benign prostatic hyperplasia/overactive bladder (ρ = 0.244). Our findings showed the Core Lower Urinary Tract Symptom Score, both its total score and each subscore, is able to show the efficacy of silodosin, similar to other questionnaires. The Core Lower Urinary Tract Symptom Score is also useful for identifying overactive bladder symptoms in patients with benign prostatic hyperplasia. As the Core Lower Urinary Tract Symptom Score does not correlate well with the Quality-of-Life index, these two questionnaires might be better used in combination to assess treatment outcomes.
    International Journal of Urology 05/2013; · 1.73 Impact Factor
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    ABSTRACT: Germline stem (GS) cells are stem cell lines derived from postnatal male germline cells. Remarkably, GS cells can form functional spermatozoa when transplanted into an infertile host mouse testes, indicating that GS cells have spermatogonial stem cell (SSC) activity. As GS cells are the only type with SSC activity, they are most suitable for in vitro studies on male germ cell differentiation. However, GS cells can deviate from the germ cell state to become other types of cells, depending on culture conditions. Therefore, it is desirable to have a monitor system to ensure that GS cells are kept at the germ cell state in culture. Here we established GS cell lines from neonatal testes of transgenic mice that express the fluorescent protein, Venus, whose gene expression is driven by the promoter of Mvh (mouse Vasa homolog), a gene highly specific to mammalian germ cells. This novel cell line has genuine GS cell properties equivalent to existing GS lines, including the ability to generate viable offspring. This Mvh-Venus GS cell line, to our knowledge, is the first one expressing a germ cell-specific reporter. This valuable resource should provide new opportunities for studies on male germ cell differentiation. © 2013 Wiley Periodicals, Inc.
    genesis 03/2013; · 2.58 Impact Factor
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    ABSTRACT: Objectives: To investigate the utility and limitations of stone surface area (SA) as a predictor of stone-free (SF) status after a single semirigid ureteroscopy (URS), with or without a flexible component, for the treatment of urinary stones. Patients and Methods: Cases of patients with urinary stones treated by combined ureteroscopy with holmium laser lithotripsy at a single institute were retrospectively evaluated. Correlations of possible predictors with SF status were analyzed using a logistic regression model. Two types of stone surface area were measured, "traced stone surface area" (tSA) and "calculated stone surface area" (cSA). Results: According to the univariate analysis, the following variables were significantly associated with non-SF: stone number (P<0.001), ureteral stone location (P=0.045), presence of renal stones (P<0.001), tSA (P<0.001), cSA (P<0.001), stone volume (P<0.001), and operator experience (P=0.02). According to multivariate analysis, stone volume (P=0.016) was an independent predictor of SF status. The scatter diagrams for tSA and cSA showed strong correlations between these parameters, and Spearman's ρ was 0.975. Conclusions: Stone volume and SA were highly indicative of stone status after single semirigid URS, with or without a flexible component. The formula for cSA, maximum diameter x width x π x 1/4, was demonstrated to accurately represent SA in this study. SA, however, indicated a lower clinical priority and utility as a predictor of stone status than stone volume. The combination of semirigid and flexible URS could access any ureteral stones, including those that semirigid URS alone could not treat. The cut-off points for these predictors of outcome were 110.0 mm2 for cSA, 125.0 mm2 for tSA, and 840.0 mm3 for stone volume.
    Journal of endourology / Endourological Society 02/2013; · 1.75 Impact Factor
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    ABSTRACT: Research on in vitro spermatogenesis has a long history and remained to be an unaccomplished task until very recently. In 2010, we succeeded in producing murine sperm from primitive spermatogonia using an organ culture method. The fertility of the sperm or haploid spermatids was demonstrated by microinsemination. This organ culture technique uses the classical air-liquid interphase method and is based on conditions extensively examined by Steinbergers in 1960s. Among adaptations in the new culture system, application of serum-free media was the most important. The system is very simple and easy to follow.
    Methods in molecular biology (Clifton, N.J.) 01/2013; 927:479-88. · 1.29 Impact Factor
  • Urology 01/2013; 81(1):217. · 2.42 Impact Factor
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    ABSTRACT: To retrospectively assess the clinical utility in ureteroscopy (URS) planning of cumulative stone diameter (CSD), which does not account for stone width or depth, as a predictor of URS outcome and compare it with stone volume. Patients with renal stones treated at a single institute by flexible URS were retrospectively evaluated. To assess the clinical utility of CSD, relationships between stone-free (SF) status and stone burden (CSD and volume) were analyzed using the area under the receiver operating characteristics (AUROC) curve. To identify stone number impact on CSD, the AUROC of CSD divided by stone number was evaluated. Correlation coefficients of CSD and stone volume were also calculated for groups by stone number. In cases with CSD <20.0 mm, CSD and stone volume revealed equal ability to predict SF status. In cases with CSD ≥20.0 mm, stone volume showed higher predictive ability. The ROC curves for cases with ≥4 stones showed that CSD was less predictive of SF status than stone volume. The correlation coefficients of CSD and stone volume by stone number were 0.922 for 1 stone, 0.900 for 2-3 stones, and 0.661 for ≥4 stones. In cases with CSD ≥20.0 mm or ≥4 stones, we should evaluate stone volume for a more predictive stone burden, and pretreatment non-contrast CT seems sufficient. In cases with CSD <20.0 mm or 1-3 stones, CSD was as valid a predictor of preoperative stone burden as stone volume, so preoperative kidney-ureter-bladder (KUB) films may be sufficient.
    PLoS ONE 01/2013; 8(6):e65060. · 3.53 Impact Factor
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    ABSTRACT: This study investigated the correlation between the operation time using two different power settings of a Ho: YAG laser. A total of 68 patients underwent cystolithotripsy from April 2010 to October 2011 In Fifty-six of these patients underwent cystolithotripsy by one surgeon using a Ho: YAG laser for bladder calculi. This study assessed these patients in two groups; the 30 W laser generator group with the settings of 2.5 J x 5 Hz (30 W group) and the 100 W laser generator group as the settings of 3.5 J x 5 Hz (100 W group). The operation time in these two groups were assessed.A total of 56 patients including 45 male and 11 female patients that underwent cystolithotripsy using a Ho: YAG laser for bladder calculi by one surgeon were enrolled in this study. The patients' characteristics including age (mean; 68.8 vs 68.4 yr), gender (male; 74.2 vs 88.0%), stone burden (mean; 34.9 vs 41.3 mm), number of stones (mean; 3.2 vs 2.0) and stone's CT density (mean; 981.5 vs 902.0 HU) showed no significant differences. All patients were stone free following treatment. The median total length of the operation was 19 minutes (mean: 34.6 ± 36.1) in the 30 W group and 29 minutes (mean: 44.4 ± 38.8) in the 100 W group, which was not significantly different. The results showed that the power settings of Ho: YAG laser show no differences in the operation time for bladder calculi lithotripsy.
    BMC Research Notes 01/2013; 6:80.
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    ABSTRACT: OBJECTIVE: To evaluate the effectiveness of cystoscopic lithotripsy, we performed Amplatz sheath technique using Ho: YAG laser. Maheshwari first reported the use of an Amplatz sheath in the female urethra in 1998, and Okeke et al reported the use of an Amplatz sheath for male patients during cystolithotripsy in 2004. The usefulness of the holmium (Ho): yttrium aluminum garnet (YAG) laser lithotripsy is widely accepted, even for large bladder calculi. Since then, there have been no more reports of using the sheath with an Ho: YAG laser. TECHNICAL CONSIDERATIONS: We inserted the Amplatz sheath conversely. Because of the clear visualization, we used higher laser settings with 2.5 J × 15 to 20 Hz. RESULTS: We experienced 3 female patients that were successfully treated with the Amplatz sheath technique using Ho: YAG laser lithotripsy. In these 3 patients, whose stone burdens were 4.5, 3.8, and 4.3 cm, they were able to successfully become stone-free with surgeries of 74 minutes, 67 minutes, and 58 minutes, respectively, with no complications. CONCLUSION: We experienced 3 female patients that were successfully treated with the Amplatz sheath technique using Ho: YAG laser lithotripsy.
    Urology 09/2012; · 2.42 Impact Factor
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    ABSTRACT: Male infertility is most commonly caused by spermatogenic defects or insufficiencies, the majority of which are as yet cureless. Recently, we succeeded in cultivating mouse testicular tissues for producing fertile sperm from spermatogonial stem cells. Here, we show that one of the most severe types of spermatogenic defect mutant can be treated by the culture method without any genetic manipulations. The Sl/Sl(d) mouse is used as a model of such male infertility. The testis of the Sl/Sl(d) mouse has only primitive spermatogonia as germ cells, lacking any sign of spermatogenesis owing to mutations of the c-kit ligand (KITL) gene that cause the loss of membrane-bound-type KITL from the surface of Sertoli cells. To compensate for the deficit, we cultured testis tissues of Sl/Sl(d) mice with a medium containing recombinant KITL and found that it induced the differentiation of spermatogonia up to the end of meiosis. We further discovered that colony stimulating factor-1 (CSF-1) enhances the effect of KITL and promotes spermatogenesis up to the production of sperm. Microinsemination of haploid cells resulted in delivery of healthy offspring. This study demonstrated that spermatogenic impairments can be treated in vitro with the supplementation of certain factors or substances that are insufficient in the original testes.
    Proceedings of the National Academy of Sciences 09/2012; 109(42):16934-8. · 9.81 Impact Factor
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    ABSTRACT: Complete staghorn calculi are typically managed with percutaneous nephrolithotomy (PCNL). However, dilating nephrostomy and inserting a nephro access sheath can be difficult to perform without hydronephrosis. We reported the procedure of ureteroscopy-assisted retrograde nephrostomy (UARN) during PCNL. UARN is effective without dilating the renal collecting system in cases of complete staghorn calculi. A 63-year old female with a left complete staghorn renal calculus was referred to our hospital. Under general and epidural anesthesia, the patient was placed in a modified-Valdivia position. A flexible ureteroscope was inserted and a Lawson retrograde nephrostomy puncture wire was advanced into the flexible ureteroscope. The puncture wire was forwarded along the route from the renal pelvis to the exit skin. Calculus fragmentation was done using a pneumatic lithotripter and the Ho: YAG laser. UARN during PCNL was effective for the treatment of a complete staghorn calculus.
    Current urology. 09/2012; 6(2):102-5.
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    ABSTRACT: The first indwelling ureteral splint was described in 1967. A ureteral stent can cause unpleasant side effects, such as urinary frequency, urgency, incontinence, hematuria, bladder pain and flank pain, which have a negative impact on a patient's quality of life. It is necessary to minimize the amount of material in the bladder in order to decrease stent-related symptoms. This study investigated the stent-related symptoms after changing from a double pigtail to a loop-type ureteral stent in the same patient group. This study followed 25 patients who underwent ureteral stent exchange from double pigtail to loop-type ureteral stent between September 2009 and February 2010. Ureteral stents were exchanged using topical, conscious sedation and general anesthesia for the various procedures including stent exchange, before/after shock wave lithotripsy and before/after ureteroscopy. The stent length was selected to be the same as whole ureteral length and the caliber based on the previous stent. A self-administered stent-related symptom questionnaire was used to assess stent-related symptoms in comparison to the previous double-pigtail stents. A total of 25 patients with a median age of 56.5 years underwent ureteral stent exchange. All patients had stone disease except two patients who had ureteral stricture. Almost all of stent-related symptoms without nocturia showed a significantly lower score with the loop-type ureteral stent than in double-pigtail stent. None of the patients experienced urinary tract infection either before or after undergoing ureteral stent exchange. Changing to loop-type ureteral stent significantly decreased ureteral stent-related symptoms.
    Urological Research 08/2012; · 1.59 Impact Factor
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    ABSTRACT: We previously reported on the effectiveness of ureteroscopy-assisted retrograde nephrostomy during percutaneous nephrolithotomy and report two cases of lower calyx calculi in horseshoe kidney that were successfully treated with ureteroscopy-assisted retrograde nephrostomy. During the ureteroscopy-assisted retrograde nephrostomy procedure, a ureteroscope is advanced in the desired calyx and a Lawson retrograde nephrostomy puncture wire is inserted. The wire is advanced through the calyx to exit the skin. The wire is then used for the percutaneous dilation. Case 1 was a 68-year-old man who was shown on radiography to have left lower calyx calculi (19 × 15mm, 7 × 5mm, and 7 × 3mm) in horseshoe kidney. Case 2 was a 36-year-old woman shown on radiography to have a left lower calyx calculus (10 × 8mm) in horseshoe kidney. Both patients were stone-free after ureteroscopy-assisted retrograde nephrostomy during percutaneous nephrolithotomy. Ureteroscopy-assisted retrograde nephrostomy is a promising procedure for safely and effectively treating lower calyx stones in horseshoe kidney.
    Journal of Medical Case Reports 07/2012; 6(1):194.
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    ABSTRACT: A 33-year-old male with an ileal conduit was referred to our department for the treatment of left renal calculi. After inserting a ureteral access sheath, a ureteroscopy-assisted retrograde nephrostomy was made. Percutaneous nephrolithotomy was successfully achieved using this nephrostomy.
    Case reports in nephrology and urology. 07/2012; 2(2):113-7.
  • Journal of endourology / Endourological Society 06/2012; 26(7):926. · 1.75 Impact Factor
  • Urological Research 06/2012; · 1.59 Impact Factor