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Featured researches published by Teppei Takeshima.


Journal of Medical Case Reports | 2017

Onco-testicular sperm extraction (onco-TESE) for bilateral testicular tumors: two case reports

Sohgo Tsutsumi; Takashi Kawahara; Teppei Takeshima; Sawako Chiba; Koichi Uemura; Masako Otani; Kota Shimokihara; Yutaro Hayashi; Taku Mochizuki; Daiji Takamoto; Yusuke Hattori; Jun-ichi Teranishi; Yasuhide Miyoshi; Masahiro Yao; Yoshiaki Inayama; Yasushi Yumura; Hiroji Uemura

BackgroundMost patients with testicular cancer are infertile; thus, the preservation of the sperm after surgery is an important factor to consider. We report two cases of bilateral testicular cancer in patients who underwent bilateral higher orchiectomy and simultaneous testicular sperm extraction.Case presentationTwo Asian-Japanese men were referred to our hospital with bilateral testicular tumors. Both of the patients were preoperatively diagnosed with azoospermia and requested testicular sperm extraction at the time of higher orchiectomy. In one patient, sperm was successfully harvested and then frozen. In the other patient, sperm could not be retrieved from the patient’s testis. In both patients, the pathological diagnosis was seminoma. Testicular tumors often occur in patients of reproductive age. The preservation of sperm before chemotherapy or bilateral orchiectomy is necessary for patients with testicular tumors who wish to be fathers.ConclusionsOnco-testicular sperm extraction might be an option for patients with testicular cancer and azoospermia or severe oligospermia.


Asian Journal of Andrology | 2017

Inverse correlation between reactive oxygen species in unwashed semen and sperm motion parameters as measured by a computer-assisted semen analyzer.

Teppei Takeshima; Yasushi Yumura; Kengo Yasuda; Hiroyuki Sanjo; Shinnosuke Kuroda; Hiroyuki Yamanaka; Akira Iwasaki

This study investigated the correlation between sperm motion parameters obtained by a computer-assisted semen analyzer and levels of reactive oxygen species in unwashed semen. In total, 847 patients, except for azoospermic patients were investigated. At the time of each patient′s first consultation, semen parameters were measured using SMAS™ or CellSoft 3000™, and production of reactive oxygen species was measured using a computer-driven LKB Wallac Luminometer 1251 Analyzer. The patients were divided into two groups: reactive oxygen species - positive and negative. The semen parameters within each group were measured using one of the two computer-assisted semen analyzer systems and then compared. Correlations between reactive oxygen species levels and sperm motion parameters in semen from the reactive oxygen species - positive group were also investigated. Reactive oxygen species were detected in semen samples of 282 cases (33.3%). Sperm concentration (P < 0.01; P < 0.01), motility (P < 0.01; P < 0.05), and progressive motility (P < 0.01; P < 0.01) were markedly lower in the reactive oxygen species - positive group than in the reactive oxygen species - negative group. Among the sperm motion parameters in the reactive oxygen species - positive group, sperm concentration (P < 0.01; P < 0.01), motility (P < 0.05; P < 0.01), mALH (P < 0.05; P < 0.01), and progressive motility (P < 0.05; P < 0.01) also showed inverse correlations with the logarithmic transformed reactive oxygen species levels. Therefore, this study demonstrated that excessive reactive oxygen species in semen damage sperm concentration, motility, and other sperm motion parameters.


Systems Biology in Reproductive Medicine | 2017

Effect of density gradient centrifugation on reactive oxygen species in human semen.

Teppei Takeshima; Yasushi Yumura; Shinnosuke Kuroda; Takashi Kawahara; Hiroji Uemura; Akira Iwasaki

ABSTRACT Density gradient centrifugation can separate motile sperm from immotile sperm and other cells for assisted reproduction, but may also remove antioxidants from seminal plasma, resulting in oxidative stress. Therefore, we investigated reactive oxygen species (ROS) concentrations and distribution in semen before and after density gradient centrifugation. We assessed semen volume, sperm concentration, sperm motility, and ROS levels before and after density gradient centrifugation (300 x g for 20 minutes) in 143 semen samples from 118 patients. The ROS removal rate was evaluated in ROS-positive samples and ROS formation rate in ROS-negative samples. Thirty-eight of 143 untreated samples (26.6%) were ROS-positive; sperm motility was significantly lower in these samples than in ROS-negative samples (p < 0.05). After density gradient centrifugation, only seven of the 38 ROS-positive samples (18.42%) exhibited a ROS-positive lower layer (containing motile sperm) with a ROS removal rate of 81.58%, whereas the upper layer was ROS-positive in 24 samples (63.16%). In the ROS-negative group (n = 105), ROS was detected in 19 samples after centrifugation (18.10%, ROS generation rate), of which 18 were ROS-positive only in the upper layer or interface and the other was ROS-positive in both layers. Density gradient centrifugation can separate motile sperm from immotile sperm as well as remove ROS (including newly generated ROS). This data supports the view that density gradient centrifugation can select motile spermatozoa without enhancing oxidative stress. Abbreviations: ROS: reactive oxygen species; SOD: superoxide dismutase; GPx: glutathione peroxidase; DNA: deoxyribonucleic acid; DGC: density gradient centrifugation; IUI: intrauterine insemination; IVF: in vitro fertilization; HEPES: 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid; EDTA: ethylenediaminetetraacetic acid; HTF: HEPES-buffered human tubal fluid; IMSI: intracytoplasmic morphologically selected sperm injection; SMAS: sperm motility analyzing system; CASA: computer-assisted semen analyzer; WHO: World Health Organization


Reproductive Medicine and Biology | 2017

Reactive oxygen species measured in the unprocessed semen samples of 715 infertile patients

Yasushi Yumura; Teppei Takeshima; Takashi Kawahara; Hiroyuki Sanjo; Shinnosuke Kuroda; Takuo Asai; Kohei Mori; Takuya Kondou; Hiroji Uemura; Akira Iwasaki

To determine whether reactive oxygen species (ROS) in semen samples could be measured with the Monolight™ 3010 Luminometer.


Molecular and Clinical Oncology | 2018

Oxidative stress marker 8-hydroxyguanosine is more highly expressed in prostate cancer than in benign prostatic hyperplasia

Shinji Ohtake; Takashi Kawahara; Yukari Ishiguro; Teppei Takeshima; Shinnosuke Kuroda; Koji Izumi; Hiroshi Miyamoto; Hiroji Uemura

Oxidative stress is a primary cause of vascular endothelial damage. In the prostate, ischemia increases the levels of reactive oxygen species, growth factors and cytokines, and induces the development of angiogenesis, which results in cancer progression. The expression levels of an oxidative stress marker, 8-hydroxyguanosine (8-OHdG), were compared between prostate cancer and non-neoplastic prostate tissues. A prostate tissue microarray composed of 10 cases of prostatic adenocarcinoma and 70 cases of benign prostatic hyperplasia was immunohistochemically stained for 8-OHdG. All cases expressed 8-OHdG. The levels of 8-OHdG expression in prostatic cancer (30.0% moderate and 70.0% strong) were significantly higher than those in benign prostatic hyperplasia (71.4% moderate and 28.6% strong; (p<0.01). Notably, 8-OHdG is expressed more highly in prostate cancer tissues in comparison to benign prostate tissues.


Clinical and Experimental Reproductive Medicine | 2018

An infertile patient with Y chromosome b1/b3 deletion presenting with congenital bilateral absence of the vas deferens with normal spermatogenesis

Shinnosuke Kuroda; Kimitsugu Usui; Kohei Mori; Kengo Yasuda; Takuo Asai; Hiroyuki Sanjo; Hiroyuki Yakanaka; Teppei Takeshima; Takashi Kawahara; Haruka Hamanoue; Yoshitake Kato; Yasuhide Miyoshi; Hiroji Uemura; Akira Iwasaki; Yasushi Yumura

We report the case of a 46-year-old Chinese male patient who visited our clinic complaining of infertility. Semen analysis revealed azoospermia, and azoospermia factor c region partial deletion (b1/b3) was detected using Y chromosome microdeletion analysis. Testicular sperm extraction was performed after genetic counseling. The bilateral ductus deferens and a portion of the epididymis were absent, whereas the remaining epididymis was expanded. Motile intratesticular spermatozoa were successfully extracted from the seminiferous tubule. On histopathology, nearly complete spermatogenesis was confirmed in almost every seminiferous tubule. To our knowledge, this is the first case report of b1/b3 deletion with a congenital bilateral absence of the vas deferens and almost normal spermatogenesis.


Clinical and Experimental Reproductive Medicine | 2018

Successful onco-testicular sperm extraction from a testicular cancer patient with a single testis and azoospermia

Shinnosuke Kuroda; Takuya Kondo; Kohei Mori; Kengo Yasuda; Takuo Asai; Hiroyuki Sanjo; Hiroyuki Yakanaka; Teppei Takeshima; Takashi Kawahara; Yoshitake Kato; Yasuhide Miyoshi; Hiroji Uemura; Akira Iwasaki; Yasushi Yumura

Onco-testicular sperm extraction is used to preserve fertility in patients with bilateral testicular tumors and azoospermia. We report the case of a testicular tumor in the solitary testis of a patient who had previously undergone successful contralateral orchiectomy and whose sperm was preserved by onco-testicular sperm extraction. A 35-year-old patient presented with swelling of his right scrotum that had lasted for 1 month. His medical history included a contralateral orchiectomy during childhood. Ultrasonography revealed a mosaic echoic area in his scrotum, suggesting a testicular tumor. The lesion was palpated within the normal testicular tissue along its edge and semen analysis showed azoospermia. Radical inguinal orchiectomy and onco-testicular sperm extraction were performed simultaneously. Motile spermatozoa were extracted from normal seminiferous tubules under microscopy and were frozen. Eventual intracytoplasmic sperm injection using the frozen spermatozoa is planned. Onco-testicular sperm extraction is an important fertility preservation method in patients with bilateral testicular tumors or a history of a previous contralateral orchiectomy.


Case Reports in Oncology | 2018

Prostate Basal Cell Carcinoma: A Case Report

Sahoko Ninomiya; Takashi Kawahara; Hiromichi Iwashita; Genta Iwamoto; Daiji Takamoto; Taku Mochizuki; Shinnosuke Kuroda; Teppei Takeshima; Koji Izumi; Jun-ichi Teranishi; Yasushi Yumura; Yasuhide Miyoshi; Takuo Asai; Hiroji Uemura

Prostate basal cell carcinoma (PBCC) accounts for 0.01% of all prostate cancers. A 68-year-old man complained of dysuria for 5 years on his initial visit. His PSA level was 3.87 ng/mL. Due to a diagnosis of benign prostate hyperplasia, he underwent transurethral resection of the prostate. A pathological examination revealed that basal cell-like atypical cells made alveolar with palisadal layout. Immunohistochemical analysis showed positive 34β12, P63, and Ki-67. Based on these findings, PBCC was diagnosed. Then, we performed radical prostatectomy. He was free from recurrence 22 months after the operation. We herein report an extremely rare case of PBCC.


Andrologia | 2018

A case of a rare variant of Klinefelter syndrome, 47,XY,i(X)(q10)

Takuya Kondo; Shinnosuke Kuroda; Kimitsugu Usui; Kohei Mori; Takuo Asai; Teppei Takeshima; Takashi Kawahara; Haruka Hamanoue; Hiroji Uemura; Yasushi Yumura

Klinefelter syndrome is a condition in which a male patient has one Y chromosome and one or more extra X chromosomes. It is the most common sex chromosome disorder. Klinefelter syndrome is distinguished by many clinical features, such as infertility, high gonadotropin and low testosterone levels, increased height, and sparse body and facial hair. We report the case of a 32‐year‐old man who visited our hospital complaining of male infertility. Semen analysis showed azoospermia, and chromosomal analysis revealed a 47,XY,i(X)(q10) karyotype, which is a rare variant of Klinefelter syndrome. No spermatozoon was found on microdissection testicular sperm extraction, and the testis biopsy histology showed only Sertoli cells and hyalinised seminiferous tubules. 47,XY, i(X)(q10) has an additional isochromosome made of the long arm of the X chromosome, which shares some features of classical Klinefelter syndrome in many aspects, but patients are usually shorter than average height and have normal intelligence. In addition, to the best of our knowledge, no successful sperm extractions from 47,XY, i(X)(q10) patients were reported in the literature. The reports of patients who have undergone microdissection testicular sperm extraction are very rare. Further reports and studies of this chromosomal abnormality are needed.


Luts: Lower Urinary Tract Symptoms | 2017

Management of urethral stricture: High-pressure balloon dilation versus optical internal urethrotomy

Yohei Kumano; Takashi Kawahara; Taku Mochizuki; Daiji Takamoto; Teppei Takeshima; Sinnnosuke Kuroda; Jun-ichi Teranishi; Kazuhide Makiyama; Yasuhide Miyoshi; Yasushi Yumura; Masahiro Yao; Hiroji Uemura

Urethral stenosis is a disease in which the lumen of the urethra becomes constricted by fibrosis. Such stenoses have been treated by urethral dilation using a bougie and optical internal urethrotomy (OIU). Recently, high‐pressure balloon dilation (BD) has been developed as a new treatment method for urethral stenosis. The present study compared the effectiveness of urethral dilation by BD and OIU.

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Yasushi Yumura

Yokohama City University Medical Center

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Shinnosuke Kuroda

Yokohama City University Medical Center

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Hiroji Uemura

Yokohama City University Medical Center

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Takashi Kawahara

Yokohama City University Medical Center

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Yasuhide Miyoshi

Yokohama City University Medical Center

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Kengo Yasuda

Yokohama City University Medical Center

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Kohei Mori

Yokohama City University Medical Center

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Takuo Asai

Yokohama City University Medical Center

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