Measurement-specific bioavailable testosterone using concanavalin A precipitation: comparison of calculated and assayed bioavailable testosterone.

OBJECTIVE: To assess the value of calculated bioavailable testosterone (cBT) and assayed BT (aBT) for the diagnosis of late-onset hypogonadism (LOH) in middle-aged and elderly subjects. METHODS: In order to assay serum BT, sex hormone-binding globulin was precipitated with concanavalin-A and then testosterone was measured using liquid chromatography-tandem mass spectrometry. To validate the non-sex-hormone-binding-globulin-bound testosterone, gel filtration chromatography and concanavalin-A sepharose were used. Following this validation, the usefulness between aBT and cBT was evaluated in clinical samples. RESULTS: Eighty-eight healthy male volunteers (mean age 65.6 years, range: 50-86) were recruited for this study. A significant correlation was found between cBT and aBT (R(2) = 0.53, P < 0.01). Mean value ratio (cBT/aBT) was 2.48. Both cBT (R(2) = 0.122) and aBT (R(2) = 0.251) decreased with age. Variations in aBT were less marked than those for cBT, suggesting that aBT can be used to determine age-related reduced testosterone levels. CONCLUSION: aBT levels are more reliable than cBT levels for the diagnosis of LOH in middle-aged and elderly subjects.

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for simultaneous measurement of salivary testosterone and cortisol in healthy men for utilization in the diagnosis of late-onset hypogonadism in males.

It is well known that late-onset hypogonadism in males can cause a variety of symptoms, and the differential diagnosis is relatively difficult, including psychological disorders, stress, and mood disturbances. The level of serum cortisol can be measured to reflect a patient's level of stress. Salivary hormones facilitate the evaluation of physiological hormonal actions based on free hormone assay. For the simultaneous measurement of testosterone and cortisol levels in saliva, we validate a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay. Concerning accuracy and precision, the lower limit of quantification of salivary testosterone and cortisol were established as 5 and 10 pg/mL, respectively. Testosterone and cortisol in saliva is stable for 2 days, 14 days, and 28 days at room temperature, refrigeration and frozen, respectively. Freezing and thawing for 3 cycles and stimulation of salivation with gum chewing do not alter the measured values of testosterone and cortisol. Total, bioavailable, and free serum testosterone showed slight diurnal changes, but total and bioavailable serum cortisol showed marked diurnal changes. Salivary testosterone levels negatively correlate with age, regardless of the time of saliva collection (r=0.64, p<0.05). However, there is no relationship between salivary cortisol and age (r=0033, p>0.05). LC-MS/MS allows rapid, simultaneous, sensitive, and accurate quantification of testosterone and cortisol in saliva for the diagnosis late-onset hypogonadism or other hormone related disease.

Single nucleotide polymorphism analysis of the follicle-stimulating hormone (FSH) receptor in Japanese with male infertility: identification of codon combination with heterozygous variations of the two discrete FSH receptor gene.

AIMS: Dysfunction of the FSH receptor (FSHR) may be involved in some form of male infertility with azoospermia or oligozoospermia. We assessed the discrete codon combination with homo/heterozygous variation of the exon 10 in the FSHR gene. METHODS: The genotype of codon 307 and codon 680 were analysed in 352 patients with idiopathic male infertility and 145 men with proven fertility. RESULTS AND CONCLUSION: There was no significant difference in the distributions of each homozygous codon 307 or 680 between these two groups as reported in the literature. However, the population with heterozygous combinations Thr/Ala (codon 307) and Ser/ Asn (codon 680) comprised 26% (38/146) and 44.9% (157/343) in subjects with proven fertility and idiopathic infertile men, respectively. Moreover, the heterozygous genotype Thr/Ala-Ser/Asn was significantly increased in infertile patients compared with the controls. This finding showed that the combination of heterozygous FSHR can be responsible for male infertility.

Modified anatrophic partial nephrectomy with selective renal segmental artery clamping to preserve renal function: a preliminary report.

OBJECTIVES: Partial nephrectomy is effective for preserving renal function, but temporary clamping of the renal artery for hemorrhagic control may impair renal function due to ischemia/reperfusion injury. Anatrophic partial nephrectomy (APNx) has been proposed to minimize renal ischemia/reperfusion injury by clamping only the feeding artery. We aimed to evaluate whether anatrophic partial nephrectomy (APNx) is useful in preserving renal function and to assess variations in renal artery anatomy to determine the feasibility of selective segmental artery clamping. METHODS: We performed preoperative renal angiography to evaluate the utility of APNx. Perioperative changes in renal function were compared between the APNx group and a standard partial nephrectomy group. RESULTS: APNx was successful in 18 patients. The mean lengths of the feeding artery on preoperative angiography were 20.5 and 6 mm for successful and unsuccessful cases, respectively. It was not difficult to clamp the feeding artery in 16 patients with lengths >10 mm or with multiple renal arteries. Evaluation of renovascular variations on 116 renal angiograms indicated that APNx was feasible for 60% and 40% on the right and left sides, respectively. The short-term increase in the serum creatinine level was significantly smaller after APNx than it was after standard partial nephrectomy. CONCLUSIONS: APNx minimizes ischemic/reperfusion injury and preserves renal function while achieving hemorrhage control. As it can be performed safely in about 50% of cases, it may be the option for patients with renal impairment or a solitary kidney.