Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 152
Filter
1.
Int J Obes (Lond) ; 41(12): 1790-1797, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28757640

ABSTRACT

BACKGROUND: Neuromedin U (NMU) is a neuropeptide with various physiological functions, including regulation of smooth-muscle contraction, blood pressure, stress responses and feeding behaviors. NMU activates two distinct receptors, NMUR1 and NMUR2, which are predominantly expressed in peripheral tissues and the central nervous system (CNS), respectively. It is reported that the NMU signaling system regulates food intake (FI) and body weight (BW) via NMUR2, suggesting that an NMUR2 agonist exhibiting anorectic effects would be a potential therapy for obesity. METHODS: Antiobesity effects of NMUR2 activation were assessed using a recently developed, novel NMUR2-selective agonist, NMU-7005 (a polyethylene glycolated octapeptide). Here we assessed cumulative FI and BW loss after peripheral administration of NMU-7005 in NMUR2 knockout and diet-induced obese mice. To gain mechanistic insights, we performed immunohistochemical analysis of c-Fos-like protein expression in the brain. RESULTS: We found that NMU-7005 was a NMUR2-selective agonist with little activity toward NMUR1. The anorectic effect of NMU-7005 was completely abrogated in NMUR2 knockout mice. Repeated subcutaneous administration of NMU-7005 showed a potent antiobesity effect with FI inhibition (P<0.025) in diet-induced obese mice. NMU-7005 in combination with the glucagon-like peptide-1 receptor (GLP-1R) agonist liraglutide showed an additive antiobesity effect, suggesting that NMUR2-mediated anorectic action is different from that of GLP-1R agonists. NMU-7005 also elicited a minimal conditioned taste-aversive effect, while the effect of liraglutide was significant. As c-Fos expression was upregulated in the hypothalamus and the medulla oblongata in NMU-7005-administered mice, the pharmacological effects of NMU-7005 appeared to be mediated via activation of the CNS. CONCLUSION: Our results demonstrated that a novel NMUR2-selective agonist, NMU-7005, is a beneficial tool for the elucidation of NMUR2-mediated physiological functions, which is a promising therapeutic strategy for treating obesity.


Subject(s)
Anti-Obesity Agents/pharmacology , Body Weight/drug effects , Eating/drug effects , Liraglutide/pharmacology , Neuropeptides/pharmacology , Obesity/drug therapy , Receptors, Neurotransmitter/agonists , Animals , Disease Models, Animal , Feeding Behavior , Immunohistochemistry , Mice , Mice, Obese
2.
Andrology ; 3(3): 520-5, 2015 May.
Article in English | MEDLINE | ID: mdl-25858496

ABSTRACT

The association between the Y chromosome haplogroup D2 and risk of azoospermia and low sperm motility has been previously studied, and it was indicated that haplogroups DE (YAP lineage) are associated with prostate cancer risk in Japanese males. Our assumption had been that Y chromosome haplogroups may be associated with sex hormone levels, because sex hormones have been deemed responsible for spermatogenesis and carcinogenesis. In this study, we assessed the association between Y chromosome haplogroups and sex hormone levels, including those of testosterone, sex hormone-binding globulin (SHBG), follicle-stimulating hormone (FSH), luteinizing hormone (LH), inhibin-B, and calculated free testosterone (cFT), in 901 young men from the general Japanese population (cohort 1) and 786 Japanese men of proven fertility (cohort 2). We found that the haplogroup D2a1 was significantly associated with high LH levels in a combined analysis involving two cohorts (ß = 0.068, SE = 0.025, p = 0.0075), following correction for multiple testing. To date, this result is the first evidence that implicates Y chromosome haplogroups in an association with sex hormone levels.


Subject(s)
Chromosomes, Human, Y/genetics , Gene Frequency/genetics , Haplotypes/genetics , Luteinizing Hormone/blood , Adult , Follicle Stimulating Hormone/blood , Humans , Inhibins/blood , Japan , Luteinizing Hormone/genetics , Male , Sex Hormone-Binding Globulin/metabolism , Testosterone/blood , Young Adult
3.
Surg Endosc ; 22(2): 430-5, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17661138

ABSTRACT

BACKGROUND: Recent typical therapy for twin-to-twin transfusion syndrome (TTTS) is selective laser photocoagulation of anastomotic communicating vessels on the placenta using the fetoscopic approach. The difficulty of a conventional laser device approach for this procedure depends significantly on the placental location, so a new robotized device is required to bend the direction of laser irradiation flexibly within the narrow uterus. METHODS: The authors designed a miniature bending mechanism impelled by a wire-guided linkage driving method that provides a stable procedure for bending laser irradiation from -90 degrees to 90 degrees . Using this bending mechanism, the authors developed a bending manipulator with a diameter of 3.5 mm and a hollow central channel with a diameter of 0.8 mm for passing a glass fiber for neodymium:yttrium-aluminum-garnet (Nd:YAG) laser photocoagulation. The bending mechanism is motorized by an electrical actuator and controlled by a grip-type interface with a small joystick. The robotized tip's part and the actuator's part are easily separable for cleaning and sterilization. RESULTS: In performance evaluations of the manipulator, the bending characteristics with a glass fiber were examined. The bending range was -52.6 degrees to 80 degrees, with a very small hysteresis error, and the bending repeatability error was 0.5 degrees +/- 0.2 degrees, which corresponds with the high accuracy of 0.2 +/- 0.1-mm positioning error at the glass fiber's tip. In the evaluation of Nd:YAG laser photocoagulation, the study confirmed that the manipulator performed effective laser photocoagulation of the placental phantom surface (underwater chicken liver). The large bending range, reaching 80 degrees, enabled a flexible approach from various directions with a high irradiation efficiency of no less than 96.6%. CONCLUSIONS: The authors' original miniature bending manipulator can change the laser irradiating direction with highly repeatable positioning accuracy for speedy, safe, and effective vessel occlusion in clinical practice.


Subject(s)
Fetofetal Transfusion/surgery , Fetoscopes , Laser Therapy/instrumentation , Miniaturization , Robotics , Equipment Design , Female , Humans , Pregnancy
4.
Hum Reprod ; 20(8): 2289-94, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15845595

ABSTRACT

BACKGROUND: Microdissection testicular sperm extraction (TESE) has provided new hope for successful sperm retrieval to patients with Sertoli cell-only syndrome (SCO). We determined expression of the inhibin alpha subunit, glial cell line-derived neurotrophic factor (GDNF) and stem cell factor (SCF) in Sertoli cells obtained from patients with SCO immunohistochemically and compared expression rates with rates of microdissection TESE sperm retrieval. METHODS: Testicular biopsy specimens were obtained from 52 men with non-obstructive azoospermia who underwent microdissection TESE and were diagnosed with SCO by histological analysis. RESULTS: All specimens showed intense staining for the inhibin alpha subunit. Moderate or intense staining for GDNF was observed in 65.8% of specimens. All but one showed moderate or intense staining for SCF. Among specimens negative for GDNF, the sperm retrieval rate was significantly higher (100%) for specimens with intense staining for SCF than for specimens with no or moderate staining (30.7%) (P<0.05) for SCF. CONCLUSION: GDNF expression differs among patients with SCO. The sperm retrieval rate was high in cases of no staining for GDNF and intense staining for SCF.


Subject(s)
Infertility, Male/pathology , Infertility, Male/therapy , Inhibins/metabolism , Nerve Growth Factors/metabolism , Stem Cell Factor/metabolism , Testis/pathology , Adult , Biomarkers/metabolism , Biopsy , Glial Cell Line-Derived Neurotrophic Factor , Humans , Immunohistochemistry , Male , Microdissection/methods , Middle Aged , Predictive Value of Tests , Sertoli Cells/pathology , Spermatozoa/cytology , Testis/cytology , Testis/metabolism
5.
Aging Male ; 8(3-4): 175-9, 2005.
Article in English | MEDLINE | ID: mdl-16390742

ABSTRACT

The purpose of this study was to evaluate the efficacy and safety of human chorionic gonadotropin (hCG) for patients with partial androgen deficiency of the aging male (PADAM). Twenty-one patients over 50 years of age with PADAM symptoms were included in this study. Laboratory and endocrinologic profiles were reviewed as appropriate, and PADAM symptoms were judged by means of several questionnaires such as the Aging Males' Symptoms (AMS) scale, short version of the International Index of Erectile Function (IIEF-5), and the Self-rating Depression Scale (SDS). Laboratory and endocrinologic values and symptom scores were evaluated and compared before and after treatment by hCG injection. The treatment period was 8.0 +/- 5.0 months (3.0-24.0 months). Serum concentrations of testosterone, including total testosterone, calculated free testosterone, and calculated bioavailable testosterone, increased significantly. AMS total scores and subscores decreased significantly after treatment. However, IIEF-5 and SDS scores did not improve. With respect to adverse effects, laboratory tests showed that only red blood cell count, hematocrit and hemoglobin level increased significantly after treatment, however, these values remained within the normal range. No adverse effect was identified after treatment. We conclude that hCG injection may be considered as a treatment for PADAM.


Subject(s)
Aging/physiology , Androgens/deficiency , Chorionic Gonadotropin/therapeutic use , Hormone Replacement Therapy , Testosterone/blood , Aged , Aging/pathology , Biological Availability , Humans , Hypogonadism/drug therapy , Male , Middle Aged , Safety , Surveys and Questionnaires , Testosterone/pharmacokinetics , Treatment Outcome
6.
Int J Impot Res ; 17(3): 259-63, 2005.
Article in English | MEDLINE | ID: mdl-15616608

ABSTRACT

The International Society for the Study of the Aging Male (ISSAM) recommends that a diagnosis be based on a patient's total testosterone (TT), calculated free testosterone (cFT), or calculated bioavailable testosterone (cBT) for partial androgen deficiency of the aging male (PADAM). The purpose of this study was to confirm whether hypogonadism of patients with PADAM is related to symptoms and clarify which criteria of testosterone recommended by ISSAM is suitable for Japanese patients. A total of 90 patients with PADAM symptoms were included in this study. Endocrinologic profiles were reviewed as appropriate, and PADAM symptoms were judged by means of several questionnaires. Laboratory values and symptoms were compared between patients with and without hypogonadism. Even when any criterion of testosterone was used for diagnosis of hypogonadism, AMS (total and subscales), IIEF-5, or SDS scores of PADAM symptoms did not differ significantly between patients classified as having and not having hypogonadism. No other endocrinologic variables than testosterone differed significantly between them, either. PADAM symptoms are not related to testosterone level and it is still obscure whether ISSAM's criterion can be adopted for Japanese patients with PADAM. Other pathology needs to be addressed for evaluation and diagnosis of PADAM in Japan.


Subject(s)
Aging , Androgens/deficiency , Andropause/physiology , Testosterone/blood , Humans , Hypogonadism/blood , Hypogonadism/diagnosis , Luteinizing Hormone/blood , Male , Middle Aged , Reference Values , Surveys and Questionnaires
7.
Transplant Proc ; 36(2 Suppl): 456S-460S, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15041387

ABSTRACT

A crossover administration of Neoral and Sandimmune was performed in 43 renal allograft recipients who had been on cyclosporine maintenance therapy for 2 to 19 years posttransplant to investigate the pharmacokinetics of cyclosporine. Although there was no difference in C0 values (trough values) when Neoral and Sandimmune were administered at the same doses, AUC(0-4) and AUC(0-12) values of Neoral were 1.57- and 1.36-fold greater than those of Sandimmune, respectively. For both Neoral and Sandimmune, there was a high correlation between the C2 value and AUC(0-4). The Pearson's product-moment coefficient for the correlation between the C2 value and AUC(0-4) was R=0.91642. On the other hand, the correlation with the C0 value (trough value) was low (R=0.53181). During the period of the study, there was no acute rejection episode, onset of adverse drug reaction symptoms, or marked change in laboratory test values.


Subject(s)
Cyclosporine/pharmacokinetics , Adult , Area Under Curve , Chemistry, Pharmaceutical , Cyclosporine/blood , Cyclosporine/therapeutic use , Drug Administration Schedule , Female , Humans , Kidney Transplantation/immunology , Kidney Transplantation/physiology , Male , Middle Aged
8.
Int J Androl ; 27(1): 32-6, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14718044

ABSTRACT

Testicular sperm extraction (TESE) combined with intracytoplasmic sperm injection is becoming a first-line treatment even for non-obstructive azoospermia. The current focus of TESE is the identification of seminiferous tubules that contain spermatozoa and minimization of testicular damage. Although microdissection TESE has been introduced as a preferred procedure for sperm retrieval, no serial follow-up studies of testicular damage have been reported. In the present study, we assayed serum testosterone concentrations and for the presence of antisperm antibodies (ASA) for 1 year after conventional multiple TESE or microdissection TESE and compared postoperative testicular damage between procedures. Thirteen patients who underwent conventional multiple TESE and 12 patients who underwent microdissection TESE were included in this study. Serum total and free testosterone concentrations were evaluated before operation and 1, 6 and 12 months after TESE. Serum ASA was also evaluated before and 12 months after TESE. Serum total and free testosterone concentrations in all patients in both groups showed no significant postoperative decrease. A comparison between the two groups of serum total and free testosterone concentrations showed no significant difference (total testosterone, p = 0.2477; free testosterone, p = 0.3098). No incidence of new ASA formation was identified in the present study. In conclusion, TESE procedures cause neither a decrease of serum testosterone nor formation of ASA. Serum testosterone concentration are similar between patients in the conventional multiple TESE and microdissection groups. Therefore, microdissection TESE is safe with respect to testicular damage, particularly for patients with hypogonadism.


Subject(s)
Antibodies/blood , Microdissection , Oligospermia/diagnosis , Spermatozoa/immunology , Testis/surgery , Testosterone/blood , Adult , Follow-Up Studies , Humans , Male , Microdissection/adverse effects , Oligospermia/etiology , Sperm Injections, Intracytoplasmic , Time Factors
9.
Arch Androl ; 50(1): 15-7, 2004.
Article in English | MEDLINE | ID: mdl-14660165

ABSTRACT

Environmental factors, changes in lifestyle and occupational exposures are responsible for declining human semen quality. We investigated the effects of history of surgery and lifestyle choices on infertility of 271 infertile men and 251 healthy volunteers. The frequency of varicocelectomy was significantly higher in infertile men (2.9%) than in controls (0.4%; P < 0.05). Alcohol use was significantly more common in infertile men (92%) than in controls (80%; P < 0.01). Satisfaction with sexual life was greater in controls (85%) than in infertile men (77%; P < 0.05). Other factors had no effect.


Subject(s)
Infertility, Male/epidemiology , Life Style , Adult , Alcohol Drinking/epidemiology , Female , Humans , Male , Maternal Age , Pregnancy , Risk Factors , Smoking/epidemiology , Surveys and Questionnaires
10.
Arch Androl ; 48(6): 467-74, 2002.
Article in English | MEDLINE | ID: mdl-12425764

ABSTRACT

This investigation was conducted to determine whether renal transplantation can improve sexual function in male patients with chronic renal failure. The authors retrospectively studied 121 men undergoing renal transplantation who complained of any type or degree of sexual dysfunction pre-operatively. Sexual function was evaluated by questionnaire which included erectile, ejaculative, and orgasmic functions. Pre- and postoperative frequency of sexual intercourse was also recorded. Patient characteristics, laboratory data, and endocrinologic profiles were analyzed to identify factors that might influence sexual function. In patients with hormonal determinations, results essentially normalized after transplantation. However, only 43 patients (35.5%) reported improvement of overall sexual function after renal transplantation, while 34 (28.1%) reported worsening. Although frequency of sexual intercourse was unaffected by transplantation, 15 of 20 patients who had no intercourse before transplantation initiated intercourse afterward. These 15 patients all underwent transplantation before 40 years of age. Comparisons of variables by sexual function showed significant differences for type of immunosuppressive treatment, interval after renal transplantation, and serum concentration of hemoglobin A1c. It is concluded that renal transplantation cannot improve sexual function in all patients, although hormonal profiles were largely normalized, and that renal transplantation should be encouraged at a younger age.


Subject(s)
Kidney Failure, Chronic/physiopathology , Kidney Transplantation , Sexual Behavior , Adult , Aged , Coitus , Humans , Kidney Failure, Chronic/surgery , Male , Middle Aged , Retrospective Studies
11.
Tissue Antigens ; 60(1): 53-63, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12366783

ABSTRACT

Non-obstructive azoospermia is a male infertility characterized by no or little sperm in semen as a result of a congenital dysfunction in spermatogenesis. Previous studies have reported a higher prevalence of particular human leukocyte antigen (HLA) antigens in non-obstructive azoospermia. As the expression of the RING3 gene located in the HLA class II region was predominant in the testis, mainly around spermatids and pachytene spermatocytes, it is tempting to speculate that RING3 is one of the strong candidate genes responsible for the pathogenesis of the disease. In this study, the genetic polymorphism in the RING3 gene was investigated by the direct sequencing technique. As a result, a total of 14 single nucleotide polymorphisms were identified. Among them, six were localized in the coding region but none of them was accompanied by an amino-acid substitution. No significant difference in the allelic distribution at these 14 polymorphic sites was observed between the patients and healthy controls, suggesting that the susceptible gene for non-obstructive azoospermia is not the RING3 gene. Then, in order to map the susceptibility locus for non-obstructive azoospermia precisely within the HLA region, 11 polymorphic microsatellite markers distributed from the SACM2L gene just outside the HLA class II region (187 kb telomeric of the DPB1 gene) to the OTF3 gene in the HLA class I region were subjected to association analysis in the patients. Statistical analysis of distribution in the allelic frequency at each microsatellite locus demonstrated that the pathogenic gene for non-obstructive azoospermia is located within the HLA-DR/DQ subregion. In fact, DRB1*1302 and DQB1*0604 were found to be strongly associated with non-obstructive azoospermia by polymerase chain reaction-based DNA typing. Further, haplotype analysis suggested that the DQB1*0604 allele may play a decisive role in the pathogenesis of non-obstructive azoospermia.


Subject(s)
Genetic Predisposition to Disease/genetics , HLA-DQ Antigens/classification , HLA-DQ Antigens/genetics , HLA-DR Antigens/classification , HLA-DR Antigens/genetics , Histocompatibility Antigens Class II/genetics , Oligospermia/genetics , Alleles , Base Sequence , Chromosome Mapping , Exons/genetics , Genetic Markers/genetics , HLA-DQ Antigens/physiology , HLA-DQ beta-Chains , Haplotypes/genetics , Histocompatibility Testing , Humans , Japan , Linkage Disequilibrium/genetics , Male , Microsatellite Repeats/genetics , Molecular Sequence Data , Polymorphism, Genetic/genetics , Sequence Deletion/genetics , Statistics as Topic
12.
Hum Reprod ; 17(11): 2924-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12407050

ABSTRACT

BACKGROUND: Testicular sperm extraction (TESE) with ICSI is becoming the first-line treatment for non-obstructive azoospermia (NOA). Recently, the sperm retrieval rate (SRR) by microdissection TESE was reported to be higher than by conventional TESE. However, a comprehensive comparison between multiple and microdissection TESE patients including histological findings has not been reported. METHODS: Patients with NOA who underwent microdissection TESE (n = 56) or multiple TESE (n = 37) were compared. Pre-operative characteristics were similar between groups. In addition, microscopic findings during microdissection TESE also were investigated. RESULTS: Operative time was significantly longer for microdissection TESE than for multiple TESE. Histological examination suggested that spermatogenesis was relatively more impaired in the microdissection TESE group than in the multiple TESE group. Despite this, SRR by microdissection TESE (42.9%) appeared higher than by conventional TESE (35.1%) although this observation failed to reach statistical significance. Seventeen of 26 patients (65.4%) with heterogeneous tubule were successful for sperm retrieval. No severe operative complications occurred in any patient in either group, and no patient required post-operative hormone replacement to treat hypogonadism. CONCLUSIONS: Microsurgical technique is safe and may improve SRR for TESE in a variety of patients with NOA, especially patients with heterogeneous testicular tubules.


Subject(s)
Dissection , Spermatozoa , Testis/surgery , Tissue and Organ Harvesting/methods , Adult , Humans , Male , Oligospermia/pathology , Oligospermia/physiopathology , Spermatogenesis , Testis/pathology , Time Factors
13.
Arch Androl ; 48(1): 29-36, 2002.
Article in English | MEDLINE | ID: mdl-11789680

ABSTRACT

The efficacy of reanastomosis was evaluated in 30 patients with obstructive azoospermia, including 19 postvasectomy cases; 7 cases complicating inguinal herniorrhaphy; 2 cases with a characterized isolated congenital anomaly; 1 case of Young's syndrome; and 1 case with an unknown, possibly congenital cause. In the postvasectomy group. successful vasovasostomy was achieved in 15 of 18 cases (83.3%; 1 postvasectomy patient dropped out of the study prior to analysis). Duration of obstruction in the 3 cases where anastomosis failed was 6, 9, and 20 years. In the group where obstruction followed inguinal herniorrhaphy, unilateral vasovasostomy was performed in 6 cases, and transepididymovasostomy was performed in 1 case. Success was achieved in 3 of 6 cases (50%; 1 case was not included because failure of spermatogenesis was detected postoperatively). In all 4 remaining cases, microsurgical epididymovasostomy or transepididymovasostomy was performed, but success was achieved only in the case of Young's syndrome. Although mailed questionnaires and telephone interviews indicated occurrence of natural pregnancy in only 4 affected couples, postoperative sperm counts were relatively satisfactory as in previous reports.


Subject(s)
Oligospermia/surgery , Adult , Female , Humans , Male , Middle Aged , Pregnancy , Pregnancy Rate
14.
Urology ; 58(6): 1064-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11744496

ABSTRACT

OBJECTIVES: To examine how hepatocyte growth factor (HGF) affects cell-cell adhesion junctions on scattering in prostate cancer cells. HGF is known to induce scattering (dispersion of clustered cells into single cells) in various epithelial cells, including prostate cancer cells, but the mechanisms surrounding this action are not fully understood. Cell-cell adhesion junctions are composed of E-cadherin and its associated intracellular catenins and play important roles in the maintenance of cell integrity. METHODS: The human prostate cancer cell line DU145 was used in this study. The associations and changes of various adhesion molecules with HGF treatment were investigated by inhibition assays, Western blot analysis, and immunofluorescence staining. RESULTS: In the inhibition assay, anti-E-cadherin neutralizing monoclonal antibody caused the dissociation of DU145 cells similar to the scattering with HGF treatment. The expression of E-cadherin decreased with HGF, and the expression of alpha-catenin and beta-catenin did not change by Western blot analysis. In immunofluorescence staining, HGF caused the translocation of E-cadherin from cell-cell adhesion junctions to the cytoplasm. CONCLUSIONS: These results indicate that HGF induces scattering by decreasing the expression of E-cadherin and causes its translocation to the cytoplasm of DU145 cells.


Subject(s)
Cadherins/physiology , Cell Communication/drug effects , Hepatocyte Growth Factor/pharmacology , Prostatic Neoplasms/pathology , Trans-Activators , Cytoskeletal Proteins/metabolism , Humans , Male , Neoplasm Proteins/metabolism , Prostatic Neoplasms/metabolism , Tumor Cells, Cultured , alpha Catenin , beta Catenin
15.
Vision Res ; 41(23): 3039-50, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11704241

ABSTRACT

It is well known that compression of visual space occurs near the saccade goal when visual stimuli are briefly flashed at various locations on a visual reference just before a saccade. We investigated how presaccadic compression of visual space affected the apparent size of an object. In the first experiment, subjects were instructed to report the apparent number of multiple bars briefly presented around the time of saccade onset. The reported number of four bars began to decline at the 50 ms mark before a saccade and reached a minimum near the saccade onset. This confirms that the compression of visual space occurs just before saccades. In the second experiment, subjects judged the apparent width of a rectangle (a single element) or four bars (four elements) presented just before saccades. The apparent width of the four-bar stimulus was compressed just before saccades, but that of the rectangle stimulus was not compressed. Experiment 3 shows that the width compression of the four-bar stimulus is consistent with the width change predicted by compression of position. These findings indicate that the shape of a single object is not distorted at the saccade goal during presaccadic compression of visual space. In addition, experiment 4 indicates that the apparent width of a flashed stimulus just before saccades depends on the processing of global shape. This extends the definition of a visual object during presaccadic compression of visual space to not only a solid element but also a constellation of multiple elements. Furthermore, the results from these experiments suggest that presaccadic compression of visual space does not prevent object recognition underlying an attentional mechanism in generating saccadic eye movements.


Subject(s)
Saccades/physiology , Size Perception/physiology , Space Perception/physiology , Adult , Female , Humans , Male , Psychometrics
17.
Arch Androl ; 47(1): 67-76, 2001.
Article in English | MEDLINE | ID: mdl-11442337

ABSTRACT

Selenoprotein P, a plasma selenoprotein, is thought to act as an antioxidant in the testis, similar to glutathione peroxidase. mRNA encoding selenoprotein P was selectively expressed by Leydig cells, suggesting participation in testosterone production. On the other hand, testosterone production has been linked to O2 toxicity in cultured Leydig cells. The authors, therefore, examined changes in selenoprotein P mRNA expression and testosterone production following stimulation by a stable analog cyclic adenosine 3',5'-monophosphate (cAMP) in cultured Leydig cells (MLTC-1 cells) under normal O2 concentrations. Selenoprotein P mRNA was analyzed by Northern blotting, while testosterone concentration in culture medium was measured by radioimmunoassay. When cAMP was added to cultures at 0, 0.01, 0.1, or 1 mM, selenoprotein P mRNA expression showed dose-dependent stimulation. cAMP was added at 0.1 mM to cultures, and the selenoprotein P mRNA expression and testosterone concentration were evaluated after incubation times of 2, 5, 9, 15, or 24 h. Selenoprotein P mRNA expression was maximal at 9 h. Testosterone concentration in the medium also increased, becoming maximal at 15 h. Selenoprotein P induced in Leydig cells following cAMP stimulation may counteract O2 toxicity from cAMP-mediated increases in testosterone production.


Subject(s)
Leydig Cells/metabolism , Proteins/physiology , Testosterone/biosynthesis , Animals , Blotting, Northern , Cyclic AMP/administration & dosage , Cyclic AMP/pharmacology , Dose-Response Relationship, Drug , Gene Expression/drug effects , Kinetics , Leydig Cells/chemistry , Male , Mice , Oxygen/administration & dosage , Proteins/genetics , RNA, Messenger/analysis , Rats , Reverse Transcriptase Polymerase Chain Reaction , Selenoprotein P , Selenoproteins , Testis/chemistry , Tumor Cells, Cultured
18.
Biol Reprod ; 65(2): 532-7, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11466222

ABSTRACT

Male juvenile spermatogonial depletion (jsd/jsd) mice are sterile because of a failure of spermatogonial differentiation. We have previously reported the recovery of spermatogonial differentiation by suppressing the levels of gonadotropins and testosterone with Nal-Glu, a GnRH antagonist. To determine whether suppression of testosterone or the gonadotropins was responsible for spermatogenic recovery, we examined the effect of supplementation of LH or FSH along with Nal-Glu treatment. Systemic administration of flutamide, an androgen receptor antagonist, was also examined. LH supplementation elevated both serum and intratesticular testosterone levels and suppressed the recovery of spermatogonial differentiation in a dose-dependent manner. Supplementation with FSH did not affect either testosterone levels or spermatogonial differentiation. Furthermore, the mice treated with flutamide showed some recovery of spermatogonial differentiation. The overall findings revealed that testosterone action mediated by androgen receptors suppressed the spermatogonial differentiation in jsd/jsd mice and suggested that spermatogonial differentiation in the jsd mutant is highly sensitive to testosterone suppression.


Subject(s)
Spermatogenesis/drug effects , Spermatogonia/cytology , Testosterone/pharmacology , Androgen Antagonists/pharmacology , Androgen Receptor Antagonists , Animals , Cell Differentiation/drug effects , Dipeptides/pharmacology , Flutamide/pharmacology , Follicle Stimulating Hormone/pharmacology , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Luteinizing Hormone/pharmacology , Male , Mice , Mice, Inbred C57BL , Receptors, Androgen/physiology , Testosterone/blood
19.
Int J Urol ; 8(5): 245-8, 2001 May.
Article in English | MEDLINE | ID: mdl-11328427

ABSTRACT

A 21-year-old man with urological symptoms was found to have a large abdominal tumor in the retrovesical space between the bladder and the rectosigmoid colon. Radiologic findings revealed little evidence confirming the diagnosis. A transrectal biopsy failed to disclose the histopathologic origin of the tumor. An exploratory laparotomy with a complete surgical resection was impossible, so a wedge biopsy was performed. Combined histologic and immunohistochemical findings revealed the features of desmoplastic small round cell tumor (DSRCT). Despite subsequent multi-agent chemotherapy, the patient died as a result of the growing tumor and liver metastasis. There have been only two prior reports of this neoplasm in the urological literature.


Subject(s)
Abdominal Neoplasms/pathology , Abdominal Neoplasms/complications , Adult , Humans , Male , Urinary Bladder , Urination Disorders/etiology
20.
J Chromatogr B Biomed Sci Appl ; 753(2): 315-20, 2001 Apr 05.
Article in English | MEDLINE | ID: mdl-11334346

ABSTRACT

A high-performance liquid chromatographic method has been developed for the simultaneous determination of mycophenolic acid (MPA) and its glucuronide conjugate (MPAG) in human plasma. The method involves protein precipitation with acetonitrile, followed by ion-pair reversed-phase chromatography on C18 column, with a 40 mM tetrabutyl ammonium bromide (TBA)-acetonitrile (65:35, v/v) mobile phase. A 20-microl volume of clear supernatant was injected after centrifugation, and the eluent was monitored at 304 nm. No interference was found either with endogenous substances or with many concurrently used drugs, indicating a good selectivity for the procedure. Calibration curves were linear over a concentration range of 0.5-20.0 microg/ml for MPA and 5-200 microg/ml for MPAG. The accuracy of the method is good, that is, the relative error is below 5%. The intra- and inter-day reproducibility of the analytical method is adequate with relative statistical deviations of 6% or below. The limits of quantification for MPA and MPAG were lower than 0.5 and 5.0 microg/ml, respectively, using 50 microl of plasma. The method was used to determine the pharmacokinetic parameters of MPA and MPAG following oral administration in a patient with renal transplantation.


Subject(s)
Chromatography, High Pressure Liquid/methods , Glucuronates/blood , Mycophenolic Acid/blood , Calibration , Glucuronates/pharmacokinetics , Glucuronides , Humans , Mycophenolic Acid/analogs & derivatives , Mycophenolic Acid/pharmacokinetics , Reference Standards , Reproducibility of Results , Sensitivity and Specificity , Spectrophotometry, Ultraviolet
SELECTION OF CITATIONS
SEARCH DETAIL
...