Leydig cell function in adolescent boys with varicoceles

The incidence of varicoceles in adolescent boys ranges from 5% to 19.5%. We studied five adolescent boys aged 17 to 20 years with visible left-sided varicoceles. All of them had public hair and testicular volumes between 20 to 25 mL and had achieved stage V of pubertal development. Serum gonadotropin response to the intravenous administration of 100 micrograms of gonadotropin-releasing hormone (GnRH) and testosterone response to the administration of 2,000 IU human chorionic gonadotropin (hCG) daily for 3 days before and 3 months after varicocelectomy were measured. Basal levels of both gonadotropins were in the pubertal range, and there was no significant difference between serum levels before and after varicocelectomy. Both gonadotropins, however, showed increased responses to the administration of GnRH (luteinizing hormone [LH]: basal, 12.0 +/- 5.1 mIU/mL; peak, 105.0 +/- 36.0 mIU/mL; follicle-stimulating hormone [FSH]: basal, 11.6 +/- 4.2 mIU/mL, peak, 60.0 +/- 18.0 mIU/ml) that decreased after varicocelectomy (LH: basal, 14.3 +/- 6.0 mIU/mL; peak, 58.6 +/- 12.0 mIU/mL; FSH: basal, 6.8 +/- 4.6 mIU/mL; peak, 38.0 +/- 8.1 mIU/mL). Serum testosterone response to hCG was also significantly improved by varicocelectomy (testosterone peak: before, 780 +/- 210 ng/dL; after, 1850 +/- 170 ng/dL). Testicular biopsy specimens showed no histologic abnormalities and normal spermatogenesis. Endocrine evaluation in adolescent boys with varicoceles could detect an early Leydig cell dysfunction that could be corrected by varicocelectomy.     

Male hypogonadism of uremic patients on hemodialysis

Primary hypogonadism occurring among uremic men on hemodialysis has been widely investigated, yet few data are available concerning the general pattern of steroidogenesis. In 161 hemodialysis patients and in 83 healthy subjects, serum levels of gonadotropins (LH and FSH), prolactin (PRL), testosterone (T), androstenedione (A), estrone (E1), estradiol (E2), and dehydroepiandrosterone-sulphate (DHEA-S) were assessed through RIA methods. Mean +/- SD hormone levels were: LH 45.6 +/- 41.1 mIU/ml, FSH 16.3 +/- 16 mIU/ml, PRL 42.4 +/- 69.1 ng/ml, A 0.83 +/- 0.27 ng/ml, E1 64.3 +/- 31.7 pg/ml, all higher than controls; T 289 +/- 125 ng/100 ml, E2 11.8 +/- 3 pg/ml, and DHEA-S 1.4 +/- 1.4 micrograms/ml, all lower than controls. The A/T and E1/E2 ratios were also higher than controls and showed a good positive linear correlation (r = 0.40; p less than 0.001) between each other. The uremic damage acts at the testis level, impairing the activity of the enzyme 17-beta-hydroxysteroid-dehydrogenase (17-OHSD), even if a derangement of the peripheral interconversion between steroids cannot be excluded.     

Varicocele ligation on free testosterone levels in infertile men with varicocele

We have analyzed the effects of varicocele ligation on free testosterone levels, and investigated the interrelationships between free testosterone and fertility. The records were retrospectively evaluated for 42 infertile patients who underwent varicocele ligation, with serum free testosterone levels, follicle stimulating hormone (FSH), lutenizing hormone (LH), testosterone, estradiol, prolactin, ejaculated volume, sperm concentration and motility before and after surgery. Serum free testosterone levels increased from 12.97+/-4.16 to 13.59+/-3.93 pg/mL, but the difference was insignificant. The differences before and after surgery of patients in sperm concentration and motility were also insignificant. However, in free testosterone increasing group, the sperm concentration and motility increased significantly, from 4.05+/-4.35 to 7.90+/-8.19 million/mL (P=0.01) and from 30.64+/-21.87% to 41.00+/-22.00%, respectively (P=0.03). The increase in serum free testosterone level by varicocele ligation results in a significant improvement in sperm concentration and motility.     

Ghrelin reduction after esophageal substitution and its correlation to postoperative body weight loss in esophageal cancer patients

BACKGROUND: Body weight loss is observed commonly after esophagectomy with gastric tube reconstruction in thoracic esophageal cancer patients. The functional and anatomical alteration of the stomach by this surgery should affect ghrelin secretion, a novel gastric hormone that upregulates body weight through appetite control and metabolic reaction. METHODS: Early-phase postoperative alteration of serum ghrelin was measured before and at day 3 and day 7 after surgery in 9 patients. With 26 other patients, who had previously undergone surgery from 3 months to 67 months (mean, 25 months) before the present study period, the late-phase postoperative alteration of serum ghrelin was investigated along with postoperative body weight loss and serum leptin. RESULTS: Serum ghrelin concentration, which was equivalent to the control group before surgery (88.6 fmol/mL vs 97.5 fmol/mL) significantly decreased by half at 3 and 7 days after surgery. Thereafter, the serum ghrelin decline continued in the outpatients within 1 year after surgery (58.8 fmol/mL), while it was marginal in those from 1 to 3 years after surgery (77.2 fmol/mL). Serum ghrelin was significantly higher than the control after 3 years (185.1 fmol/mL). Thus, a significant positive correlation was observed between ghrelin and time after surgery (P < .0001). Postoperative body weight loss was significant, averaged as DeltaBMI - 2.7 in the outpatients (P < .0001). Until 3 years after surgery, a significant correlation between ghrelin and postoperative body weight loss was observed (P = .0152), with those having higher serum ghrelin showing less body weight loss. Serum leptin correlated well with body weight (P = .0144), but not with postoperative time, the degree of body weight loss, or serum ghrelin concentration. CONCLUSION: Gastric tube replacement for esophagectomy resulted in temporary reduction of ghrelin production, which is associated with body weight loss after surgery. The decline of ghrelin may play some role in the serious body weight loss after esophagectomy, thus encouraging clinical application of exogenous recombinant ghrelin for these patients.     

Relationship between body composition,sex hormones and leptinemia in hemodialyzed patients with chronic renal failure

BACKGROUND: Females are characterized by significantly higher plasma leptin concentration than males. It seems likely that sex hormones influence leptinemia independently from differences in body composition. The aim of the present study was to analyze the contribution of plasma concentrations of testosterone and estradiol on leptinemia in hemodialyzed patients. METHODS: 110 hemodialyzed patients--HD (60 M, 50 F) and 70 healthy subjects (HS) (30 M, 40 F) were enrolled in this study. Plasma leptin, testosterone or estradiol and CRP concentrations and body composition by dual-energy X-ray absorptiometry (DEXA) were assessed. RESULTS: Total body fat was significantly higher in females than in males (27.5 +/- 1.5% vs. 17.2 +/- 1.0% of body weight in HD and 36.0 +/- 1.0% vs. 18.2 +/- 1.4% in HS, respectively). Plasma leptin concentrations were markedly higher in females than in males both in HD (27.9 +/- 5.4 ng/ml vs. 9.6 +/- 1.9 ng/ml) and HS (16.5 +/- 1.7 ng/ml vs.3.1 +/- 0.4 ng/ml). A highly significant, strong positive correlation was found between total fat mass (TFM) and leptinemia in all studied groups. No significant univaried correlation between plasma leptin and testosterone or estradiol concentrations respectively was found both in HD and HS. Multiple regression analyses showed that the main determinant of leptinemia is TFM (beta = 0.623 and 0.798 in HS females and males respectively, and beta = 1.058 and 0.797 in HD females and males respectively). Plasma concentration of testosterone (beta = -0.139 and beta = -0.075 in male HD and HS respectively) and estradiol (beta = 0.199 and beta = 0.046 in females HD and HS, respectively) contributed to leptinemia only in a minor degree. CONCLUSION: Both testosterone and estradiol are minor contributors to leptinemia both in HS and HD patients. The main determinant of leptinemia in these subjects is total body fat mass.     

Peritoneal clearance of leptin in CAPD patients: impact of local insulin administration.

INTRODUCTION: The ob gene product leptin is secreted by fat cells and the serum leptin levels reflects the body fat content. Markedly elevated serum leptin levels have been reported in patients with chronic renal failure. The aim of the present study was to assess if the dialysate leptin levels in peritoneal dialysate are similar to what can be expected from passive diffusion or if intraperitoneal synthesis of leptin may occur. METHODS: We studied 39 patients (20 males), mean age 54+/-12 years, who had been treated with peritoneal dialysis for 17+/-12 months. Ten of the patients were diabetics of which seven used intraperitoneal insulin. A 24-h collection of dialysate was performed and dialysate and fasting blood samples were analysed for leptin, albumin and beta2-microglobulin, and the peritoneal clearances (PCl) were calculated for these solutes. RESULTS: Serum leptin (mean 47+/-76, range 3-350 ng/ml) was related to body mass index (r=0.35, P<0.05). In multiple regression analysis, serum leptin also correlated to serum TNF-alpha. Although dialysate leptin levels correlated to serum leptin, they were higher than expected from the molecular weight of 16 kD. PCl of leptin was 1.3 ml/min (range 0.2-5.9 ml/min), which was 1.6 times higher than expected from the molecular weight of leptin and PCl for albumin and beta2-microglobulin, not taking the protein binding of leptin into account. A strong correlation was found between PCI for albumin and beta2-microglobulin (r = 0.68, P < 0.0001) but neither PCl albumin, nor PCl beta2-microglobulin correlated to PCI leptin. The PCl of leptin was markedly higher in diabetics using intraperitoneal insulin (n = 7) compared to the other 32 patients (2.6+/-2.0 vs 1.1+/-0.7 ml/min, P<0.05). CONCLUSION: Serum leptin is locally produced in the peritoneal cavity, and intraperitoneal insulin enhances local production of leptin.     

Serum leptin as a determinant of bone resorption in healthy postmenopausal women

To examine the relationships between serum leptin and bone metabolism, we measured bone mineral density (BMD) at the spine and the hip, fasting serum leptin, and osteocalcin and urinary excretion of C-terminal crosslinking telopeptide of type I collagen (CTX), as markers of bone formation and resorption, respectively, in 121 postmenopausal women aged 54 +/- 5 years. These parameters were also assessed at 6 months and 2 years of treatment with either 2.5 mg tibolone (n = 34), 1.25 mg tibolone (n = 45), or 2 mg estradiol plus 1 mg norethindrone acetate (n = 42). At baseline, serum leptin correlated positively with spine (r = 0.21, P = 0.02) and total hip (r = 0.26, P = 0.0044) BMD and negatively with CTX (r = -0.38, P < 0.0001) and osteocalcin (r = 0.21, P = 0.025). After adjustment for BMI and for fat mass, the association between serum leptin and CTX persisted with a partial correlation coefficient of -0.18 (P = 0.046) and of -0.22 (P = 0.03), respectively. Women in the highest quartile of leptin levels had 11% higher total hip (P = 0.0039) and lumbar spine BMD (P = 0.016), 21% lower osteocalcin (P = 0.01), and 38% lower CTX (P = 0.0005) than women in the lowest quartile (P < 0.05). During treatment, serum leptin levels increased (+14.7 +/- 47.3%, P = 0.019), without significant difference between the groups. This increase correlated with the increase in body weight (r = 0.46, P < 10(-4)). No correlation was found between the changes in leptin and the changes in bone parameters. In conclusion, leptin may play a role as a determinant of bone resorption in healthy, untreated postmenopausal women, but the effect of estradiol or tibolone on bone are not mediated by leptin.     

Routine screening for classical azoospermia factor deletions of the Y chromosome in azoospermic patients with Klinefelter syndrome

Aim： To evaluate the occurrence of classical azoospermia factor （AZF） deletions of the Y chromosome as a routine examination in azoospermic subjects with Klinefelter syndrome （KS）. Methods： Blood samples were collected from 95 azoospermic subjects with KS （91 subjects had a 47,XXY karyotype and four subjects had a mosaic 47,XXY/46, XY karyotype） and a control group of 93 fertile men. The values of testosterone, follicle stimulating hormone （FSH） and luteinizing hormone （LH） were measured. To determine the presence of Y chromosome microdeletions, polymerase chain reaction （PCR） of five sequence-tagged site primers （sY84, sY 129, sY 134, sY254, sY255） spanning the AZF region, was performed on isolated genomic DNA. Results： Y chromosome microdeletions were not found in any of the 95 azoosperrnic subjects with KS. In addition, using similar conditions of PCR, no microdeletions were observed in the 93 fertile men evaluated. The level of FSH in KS subjects was higher than that in fertile men （38.2 ± 10.3 mIU/mL vs. 5.4 ±2.9 mIU/mL, P 〈 0.001） and the testosterone level was lower than that in the control group （1.7 ±0.3 ng/mL vs. 4.3 ± 1.3 ng/mL, P 〈 0.001）. Conclusion： Our data and review of the published literature suggest that classical AZF deletions might not play a role in predisposing genetic background for the phenotype of azoospermic KS subjects with a 47,XXY karyotype. In addition, routine screening for the classical AZF deletions might not be required for these subjects. Further studies including partial AZFc deletions （e.g. gr/gr or b2/b3） are necessary to establish other mechanism underlying severe spermatogenesis impairment in KS.     

Comparison of effects of gastric bypass and biliopancreatic diversion with duodenal switch on weight loss and body composition 1-2 years after surgery.

BACKGROUND: Gastric bypass (GB) is the most common surgical procedure for weight loss in the United States. Biliopancreatic diversion with duodenal switch (BPD/DS) is less routinely performed, perhaps because of its technical difficulty and metabolic concerns. The objective of this study was to determine whether these procedures had differential effects on weight loss and body composition. METHODS: Body composition was measured by bioimpedance (Tanita 310) at the initial consultation, and follow-up measurements were completed 1-2 years after surgery. RESULTS: Of the 72 patients in the study, 50, aged 46.2 +/- 8.5 years, had undergone GB and were measured 15.5 +/- 5.2 months after surgery and 22, aged 40.6 +/- 7.9 years, had undergone BPD/DS and were measured 19.5 +/- 7.5 months after surgery. Patient age and time after surgery were significantly different between the 2 groups. The body mass index (BMI) for the BPD/DS group was 53.6 +/- 11.9 kg/m(2), significantly greater than the BMI of the GB group (48.0 +/- 6.3 kg/m(2); P = .009). However, the percentage of body fat did not differ between the 2 groups (P = .515). Postoperatively, the BMIs for the GB group (31.5 +/- 5.0 kg/m(2)) and BPD/DS group (30.3 +/- 6.1 kg/m(2)) were not significantly different (P = .384). The percentage of body fat for the GB and BPD/DS groups had changed from 49.2% +/- 8.3% to 32.1% +/- 10.6% and 47.9% +/- 5.9% to 23.8% +/- 10.4%, respectively (P = .002). The BMI had decreased by 16.5 +/- 4.8 kg/m(2)after GB and 23.3 +/- 6.8 kg/m(2) after BPD/DS (P <.001). The decrease in fat was 17.1% +/- 8.2% after GB and 24.2% +/- 7.2% after BPD/DS (P <.001). CONCLUSION: The BPD/DS procedure is more effective in reducing the BMI and promoting fat loss than is GB. The assessment of the impact of these two operations on an individualized basis offers additional information to assist in the evaluation of these procedures.     

Testosterone decreases adiponectin levels in female to male transsexuals

Aim:To evaluate the effect of testosterone(T)on adiponectin serum levels in transsexual female patients.Methods:We measured adiponectin,leptin,luteinizing hormone and follicle stimulating hormone,T,estradiol,lipid profile,biochemical parameters and body composition in 16 transsexual female patients at baseline and after 6 months of Ttreatment(100mg Testoviron Depot/10 days,i.m.).Results:Adiponectin levels were 16.9±7.3 mg/mL at baselineand 13.5±7.4 mg/mL at month 6 of T treatment(P<0.05).Leptin and high-density lipoprotein cholesterol decreasedsignificantly,whereas body mass index,waist circumference and lean body mass increased significantly after 6months of T treatment.No changes in insulin or Homeostasis Model Assessment were detected.Conclusion:T cansignificantly reduce adiponectin serum levels in transsexual female patients.(Asian JAndro12006 Nov;8:725-729)     

Sirolimus Impairs Gonadal Function in Heart Transplant Recipients

The impact of sirolimus on hormone levels involved in the hypothalamus-pituitary-gonad axis in male heart transplant recipients was investigated. A pair-matched analysis with 132 male heart transplant recipients on either sirolimus based- or calcineurin inhibitor-based immunosuppression was performed. Matching criteria were age, years after transplantation and creatinine levels. Measured parameters were testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), sexual hormone-binding globulin (SHBG) and free androgen index (FAI). Mean testosterone was 3.86 +/- 1.41 ng/mL in the sirolimus group and 4.55 +/- 1.94 ng/mL in the controls (p = 0.025). Serum LH was 12.82 +/- 11.19 mlU/mL in the sirolimus patients and 6.2 +/- 5.25 mlU/mL in the controls (p = 0.015). Follicle stimulating hormone levels were 13.31 +/- 18.4 mlU/mL vs. 7.32 +/- 5.53 mlU/mL, respectively (p = 0.015). The analysis revealed a significant decrease in testosterone and a significant increase in FSH and LH in the sirolimus group. The duration of sirolimus treatment correlated positively with SHBG (p < 0.01), LH (p < 0.05) and FSH (p < 0.05) and negative with the FAI (p < 0.05). Sirolimus trough levels correlated with LH and FSH levels (p < 0.01). Heart transplant recipients treated with sirolimus revealed significantly lower testosterone levels and a significant increase in gonadotropic hormones. These effects were trough-level dependent. All candidates awaiting organ transplantation should be informed about these adverse effects.     

Peritoneal clearance of leptin in continuous ambulatory peritoneal dialysis.

Leptin is a 16-kd protein that increases energy expenditure and limits food intake. Serum leptin (S-leptin) is elevated in dialysis patients, and little data have been reported on leptin clearance (Cl) during dialysis. We analyzed the peritoneal dialysis (PD) Cl of leptin in 15 continuous ambulatory peritoneal dialysis (CAPD) patients and compared the results to beta(2)-microglobulin (beta(2)-m), urea, and creatinine PD Cl. S-leptin was significantly elevated (Kruskal-Wallis, P < 0.005) in CAPD women (58.4 +/- 42.4 [SE] microg/L, n = 5) as compared with CAPD men (13.9 +/- 7.1, n = 10) and with healthy women (11.0 +/- 1.4, n = 13) and men (5.1 +/- 0. 9, n = 14). Correlations were found between percent of fat mass and S-leptin (P < 0.05); between S-leptin and the 24-hour PD leptin (P < 0.05); and between dialysate-to-plasma (D/P) beta(2)-m and D/P leptin (P < 0.01). PD leptin Cl (1.80 +/- 0.43 mL/min/1.73 m(2)) was higher than beta(2)-m Cl (1.22 +/- 0.31) (P < 0.01), but reduced as compared with urea Cl (8.84 +/- 1.20) (P < 0.005) and creatinine Cl (7.71 +/- 0.99) (P < 0.005). These results indicate that leptin is eliminated through the peritoneum membrane. However, peritoneal leptin clearance, as beta(2)-m, appears to be clearly restricted as compared with peritoneal transport of smaller molecules. Hence, leptin could use the same diffusion transport pathway as beta(2)-m. In addition, leptin, which has a higher molecular weight than beta(2)-m, was significantly more eliminated into the peritoneal dialysate. More studies are necessary to clarify whether this is an active leptin elimination process by peritoneal secretion or by a different restriction coefficient of diffusion through the peritoneum membrane.     

Serum inhibin pro alphaC in infertile men.

Specific assays have been developed for bioactive inhibin dimers, inhibin A and B, and inhibin alpha-subunit precursor pro alphaC. To better understand the role of serum inhibin pro alphaC in infertile men, the authors measured these forms of inhibin in sera from 39 infertile men and analyzed inhibin relationships with serum gonadotropins, testosterone, and estradiol. All subjects had oligozoospermia. Inhibin A levels were undetectable in all subjects. Inhibin B concentrations were 117 +/- 59 pg/mL. Inhibit B concentrations correlated negatively with serum FSH (r = .584, p < .0001) and positively with sperm count (p < .01) and bilateral testicular volume (r = .607, p < .0001). The concentration of pro alphaC was 556 +/- 236 pg/mL (normal range, 446 +/- 28). Inhibin pro alphaC showed no correlation with serum FSH, LH, testosterone, sperm concentration, and bilateral testicular volume. In addition, inhibin pro alphaC was not correlated with inhibin B. Pro alphaC is unlikely to be a useful marker for spermatogenesis in infertile men compared with inhibin B.     

Effect of hyperprolactinemia and age on the hypogonadism of uremic men on hemodialysis

Primary hypogonadism has been commonly reported among uremic men on hemodialysis, characterized by low testosterone levels, increased luteinizing hormone and sometimes follicle-stimulating hormone levels. Little is known about the influence of hyperprolactinemia and age on this hypogonadism. In 149 hemodialysis patients and in 60 healthy subjects the serum levels of testosterone (T), gonadotropins (LH and FSH) and prolactin (PRL) were assessed through radioimmunoassay. Mean +/- SD hormone levels were: T 274 +/- 125 ng/100 ml, lower than controls; LH 44.7 +/- 46.1 mlU/ml and FSH 17.6 +/- 18.4 mIU/ml, both higher than controls. PRL 31.3 +/- 49.4 ng/ml, higher than controls. A positive correlation between LH and FSH, a negative correlation between PRL and both T and LH was found. Moreover T and FSH were correlated with age only in the normoprolactinemic patients. These data suggest: a common damaging mechanism by uremia on both interstitial and tubular structures of the testis; a central antigonadal influence of hyperprolactinemia even if a direct action on the testis cannot be excluded; a worsening action of age on the gonadal function of these patients.     

Endocrine patterns in patients with benign and malignant prostatic diseases

BACKGROUND: The known importance of the endocrine system, particularly of steroid hormones, for development of the prostate gland and the fact that steroid hormones act as immunmodulators prompted us to compare hypophyseal, adrenal, and gonadal hormones, including cortisol, in patients with benign and malignant prostatic diseases. METHODS: Patients with newly diagnosed, untreated prostate cancer (PC) (n = 75) and, as a control population, those with untreated lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) (n = 159) entered this prospective study. In all patients, the following parameters were obtained by serum analysis: prostate-specific antigen (PSA), human luteinizing hormone (hLH), human follicle-stimulating hormone (hFSH), testosterone, estradiol (E2), cortisol, and dehydroepiandrosterone-sulphate (DHEA-S). Serum samples were collected of fasting patients between 7. 30-10.00 AM. RESULTS: Age was comparable in both groups (PC: 65.6 +/- 7.6 years (mean +/- standard deviation) vs. controls: 64.9 +/- 8. 1 years; P = 0.56). HFSH (PC: 6.6 +/- 3.9 mIU/ml; controls: 8.4 +/- 6.4 mIU/ml; P = 0.04), hLH (PC: 5.3 +/- 4.8mIU/ml; controls: 7.6 +/- 6.2 mIU/ml; P = 0.009), and estradiol (PC: 25.8 +/- 12.7 pg/ml; controls: 32.6 +/- 12.6 pg/ml; P = 0.0003) were significantly lower in PC patients than controls. Cortisol (PC: 16.7 +/- 4.2 microg/dl; controls: 13.5 +/- 4.3 microg/dl; P < 0.0001) was significantly higher in cases. The difference for cortisol and estradiol concentrations between PC patients and controls held true in all life-decades. Serum concentrations for DHEA-S and testosterone were comparable between PC and control patients. In PC patients, none of the endocrine parameters correlated to serum PSA or clinical/pathological stage. CONCLUSIONS: Patients with newly diagnosed, untreated PC yielded significantly higher cortisol and lower estradiol serum concentrations than controls. The known effect of cortisol on the immune status warrants further studies.     

Correlation of serum leptin concentrations with body composition and gender in Taiwanese hemodialysis patients without diabetes

OBJECTIVE: (1) To evaluate the impact of body composition and gender on serum leptin concentration in hemodialysis patients. (2) To study which marker of adiposity is most appropriate in Taiwanese hemodialysis patients without diabetes. (3) To compare the nutrition status between nonlean and lean subjects. PATIENTS AND METHODS: Serum leptin concentrations were measured by radioimmunoassay collected in 88 hemodialysis patients without diabetes. Bioimpedance analysis was performed to determine percent fat mass (%FM), lean body mass (LM), and total body water (TBW). Body mass index (BMI) was calculated as weight/height2. Albumin and transferrin were measured by standard laboratory methods. RESULTS: Serum leptin levels were more correlated with percent fat mass (r = 0.697; P < 0.001) than with body fat mass (r = 0.672; P < 0.001) or with BMI (r = 0.594; P < 0.001) in the group as a whole and in each subgroup when analyzed separately by gender. The mean (+/- SD) serum leptin levels were 32.5 +/- 34.3 ng mL(-1) in women subjects and 13.6 +/- 15.5 ng mL(-1) in men subjects (P < 0.001). Multiple regression analysis in all subjects revealed that serum leptin levels were independently affected by percent fat mass and gender. Adiposity corrected serum leptin, such as leptin/BMI, leptin/percent fat mass, and leptin/body fat mass was significantly different between sexes (P < 0.001). The significantly higher serum leptin concentrations in women than in men were observed in obese subjects with BMI > 25 kg/m2 (P < 0.001) as well as nonobese subjects with BMI < 25 kg/m2 (P < 0.05). There were no differences in lean mass and albumin between nonlean and lean subjects. CONCLUSION: Gender and adiposity had impact on serum leptin levels in hemodialysis patients without diabetes. In terms of adiposity, serum leptin levels had stronger correlation with percent fat mass than with body fat mass (FM) or BMI in Taiwanese hemodialysis patients. Steady-state serum leptin levels could serve as valuable clinical markers for the body adiposity in stable hemodialysis patients without diabetes. Protein malnutrition markers and lean mass should be checked in lean subjects for the evaluation of the protein stores of hemodialysis patients.     

Disruption of the Leptin-Insulin Relationship in Obese Men 24 Hours after Laparoscopic Adjustable Silicone Gastric Banding

Background:The placement of a band to attain a tiny stomach pouch has been reported to produce early satiety in patients undergoing gastric banding. The adipocyte-derived hormone, leptin, has been shown to decrease both food intake and body weight. The aim of the present study was to assess the potential involvement of acute changes in leptin concentrations following laparoscopic adjustable silicone gastric banding (LASGB). Methods:The study groups comprised obese male patients undergoing bariatric surgery by LASGB and overweight men undergoing laparoscopic Nissen fundoplication (NFd). Blood was drawn before surgery and 24 hours postoperatively for glucose, insulin and leptin measurements. Results: In both experimental groups, a statistically significant decrease was observed in pre- and postsurgery glucose (LASGB 111 ± 8 vs 99 ± 6 mg/dl, P<0.01; NFd 107 ± 7 vs 98 ± 5 mg/d, P<0.01) and insulin concentrations (LASGB 39.8 ± 11.9 vs 32.9 ± 10.3 U/l, P<0.01; NFd 13.2 ± 3.3 vs 12.2 ± 2.9 U/l, P<0.05). However, no significant differences were observed when the percent change from pre-surgery values was analysed between both groups. Following surgery, an increase in leptin concentrations was observed in the LASGB group (23.5 ± 4.7 vs 37.5 ± 6.8 μg/l, P<0.001) whereas a small decrease was evident in the NFd patients (12.9 ± 4.6 vs 8.9 ± 2.2 μg/l, P<0.01). Conclusion: These findings strongly suggest that the short-term increase observed in plasma leptin concentrations following LASGB may play a key role in triggering an early satiety signal due to the modi fication of the gastrointestinal anatomy and physiology.     

Cytokine response to surgical stress: comparison of pure laparoscopic, hand-assisted laparoscopic, and open nephrectomy

BACKGROUND AND PURPOSE: Laparoscopic surgery has been shown to induce less immune suppression than open surgery, presumably because there is less tissue trauma, a factor that may impact oncologic-disease control. The objective of this study was to compare the cytokine and stress response associated with pure laparoscopic, hand-assisted laparoscopic (HAL), and open nephrectomy. MATERIAL AND METHODS: Fifteen female farm pigs (45-50 kg) underwent transperitoneal laparoscopic, handassisted (HAL), or open nephrectomy (N = 5 in each group). At 1, 4, 24, and 48 hours post-nephrectomy, blood and peritoneal fluid samples were collected for measurement of tumor necrosis factor (TNF) alpha, interleukin (IL)-1beta, and IL-6 using enzyme-linked immunosorbent assay (ELISA) techniques. Body temperature and serum glucose and cortisol were also measured. RESULTS: No evidence of perioperative infection was detected in any animal through temperature and glucose monitoring. Operating time and blood loss were comparable among the three groups. Peak serum cortisol concentrations were significantly higher in the HAL group than in the pure laparoscopic group at 24 hours (P = 0.02). Serum TFNalpha concentrations were significantly lower in the pure laparoscopy group (40 +/- 6 pg/mL) than in the HAL and open-nephrectomy groups (81 +/- 6 pg/mL and 83 +/- 17 pg/mL, respectively; P < 0.05), although no differences between groups were found in the serum IL-1beta and IL-6 concentrations. Peritoneal IL-1beta was significantly higher in the HAL than in the open-nephrectomy group (2993 +/- 507 pg/mL and 733 +/- 185 pg/mL, respectively; P = 0.05). Peritoneal IL-6 was significantly lower in the pure laparoscopy group (694 +/- 234 pg/mL) than in the open-surgery group (1668 +/- 312 pg/mL) (P = 0.04). CONCLUSION: Pure laparoscopic surgery in pigs elicits a less-robust cytokine response than HAL or open nephrectomy with respect to serum TNFalpha and peritoneal IL-6 concentrations, perhaps reflecting less impairment of the immune system. Clinical confirmation is required, and the implications with regard to oncologic tumor surveillance in humans require further study.     

Secretion of A-type and B-type natriuretic peptides into the bloodstream and pericardial space in children with congenital heart disease

OBJECTIVE: To determine the secretion of A-type and B-type natriuretic peptides into the bloodstream and pericardial space in children with congenital heart disease. METHODS: Plasma and pericardial fluid samples were obtained from 77 patients undergoing total correction for congenital heart disease. All patients underwent detailed right-sided and left-sided cardiac catheterization preoperatively. RESULTS: A-type natriuretic peptide levels in pericardial fluid were lower than those in plasma (33.0 +/- 23.1 versus 39.8 +/- 33.6 pg/mL, P <.05), and B-type natriuretic peptide levels in pericardial fluid showed marked elevations compared with those in plasma (231.9 +/- 305.6 versus 19.8 +/- 29.3 pg/mL, P <.0001). The A-type and B-type natriuretic peptide levels in plasma correlated with those in pericardial fluid (R =.522, P <.0001; R =.595, P <.0001). For A-type and B-type natriuretic peptide levels in plasma, the relation with biventricular volume had the highest correlation (R =.669, P <.0001; R =.652, P <.0001). The patients with a pulmonary-to-systemic flow ratio greater than 2 (n = 19) had high levels of natriuretic peptides not only in plasma (58.3 +/- 43.2, 40.5 +/- 49.4 pg/mL, P <.05) but also in pericardial fluid (44.4 +/- 31.5, 287.2 +/- 198.5 pg/mL, P <.05), and higher correlation between A-type and B-type natriuretic peptide plasma levels and left ventricular volume (R =.913, P <.0001; R =.787, P <.0001). CONCLUSIONS: B-type natriuretic peptide is secreted not only into the bloodstream but also into the pericardial space in children with congenital heart disease. Natriuretic peptide levels in plasma correlated well with biventricular volume. The left ventricle was considered to be the main source of secreted natriuretic peptides in the patients with a pulmonary-to-systemic flow ratio greater than 2.     

Does vagal nerve stimulation affect body composition and metabolism? Experimental study of a new potential technique in bariatric surgery

BACKGROUND: It has been shown that vagal nerve stimulation (VNS) can affect body mass. The aim of this study was to evaluate effect of VNS on body mass, body composition, metabolic rate, and plasma leptin and IGF-I levels. METHODS: Eight female pigs were included in the study. Under general anesthesia, a bipolar electrode was implanted on the anterior vagal nerve by laparoscopy. Group A was treated by VNS, and group B was the control. After 4 weeks, stimulation was discontinued in group A and started in group B. The following parameters were evaluated: body mass, body composition, metabolic rate, plasma leptin and IGF-1 levels and intramuscular fat content (IMF). RESULTS: VNS attenuated body weight gain (2.28 +/- 3.47 kg vs 14.04 +/- 6.75 kg; P = .0112, for stimulation and nonstimulation periods, respectively), backfat gain (0.04 +/- 0.26 mm vs 2.31 +/- 1.12 mm) and IMF gain (-3.76 +/- 6.06 mg/g MS vs 7.24 +/- 12.90 mg/g MS; P = .0281). VNS resulted in lower backfat depth/loin muscle area ratio (0.33 +/- 0.017 vs 0.38 +/- 0.35; P = .0476). Lower plasma IGF-I concentration was found after VNS (-3.67 +/- -11.55 ng/mL vs 9.86 +/- 10.74 ng/mL; P = .0312). No significant changes in other parameters were observed. CONCLUSIONS: VNS affects body weight mainly at the expense of body fat resources; however, metabolic rate is not affected.