bluuebunny/crossref_metadata_2025 huggingface dataset:
A boundary integral method for computing forces on particles in unsteady Stokes and linear viscoelastic fluids
Authors: Feng H. , Córdoba A. , Hernandez F. , Indei T. , Li S. , Li X. , Schieber J. D.
Published: December 2015

Accurately characterizing the forces acting on particles in fluids is of fundamental importance for understanding particle dynamics and binding kinetics. Conventional asymptotic solutions may lead to poor accuracy for neighboring particles. In this paper, we develop an accurate boundary integral method to calculate forces exerted on particles for a given velocity field. We focus our study on the fundamental two‐bead oscillating problem in an axisymmetric frame. The idea is to exploit a correspondence principle between the unsteady Stokes and linear viscoelasticity in the Fourier domain such that a unifying boundary integral formulation can be established for the resulting Brinkman equation. In addition to the dimension reduction vested in a boundary integral method, our formulation only requires the evaluation of single‐layer integrals, which can be carried out efficiently and accurately by a hybrid numerical integration scheme based on kernel decompositions. Comparison with known analytic solutions and existing asymptotic solutions confirms the uniform third‐order accuracy in space of our numerical scheme. Copyright © 2016 John Wiley & Sons, Ltd.
Reliability Evaluation of an Open‐Cathode PEMFC at Operating State and Longtime Vibration by Mechanical Loads
Authors: Imen S. J. , Shakeri M.
Published: December 2015

Reliability and durability of proton exchange membrane fuel cells (PEMFCs) are one of the most complex issues in real applications' environment. Especially, when it subjects to the various mechanical loads and vibrations. This topic requires more attention for research and experimental works. In this study, the effect of mechanical loads was investigated on an open‐cathode PEMFC in operating state. Several long time vibration tests have been applied on non‐operating PEMFC, and the performance of the fuel cell was evaluated during the test. Hydrogen leakage as a key parameter was investigated in performance monitoring instead of measuring torque on compression bolts. The vibration tests were consisted of sine, shock and random for X, Y and Z axes in operating state and random vibration in non‐operating state of PEMFC. The experimental results in operating state were indicated that the fuel cell performance has not been affected by the proposed vibrations. Furthermore, the test results of non‐operating state have been shown that the performance of PEMFC reduces about 0.6% in each four‐hour step of the vibration test. In addition, the experiments reveal that if the mechanical loads and vibrations cause physical damage on the fuel cell components, they can change the performance and reliability of the fuel cell.
Evaluation of Temazepam as a Hypnotic
Authors: Mitler Merrill M.
Published: December 2015

Temazepam is a 1,4‐benzodiazepine, newly marketed in the United States for the symptomatic treatment of the complaint of insomnia. The manufacturer recommends a dose of 30 mg before bedtime for most adults and 15 mg for geriatric or debilitated patients. A dose of 30 mg usually produces peak plasma concentrations within 3 hours after oral ingestion and has a mean half‐life of 10 to 15 hours. Thus, temazepam is absorbed more slowly and metabolized more quickly than flurazepam, the only other benzodiazepine marketed in the United States specifically for insomnia. Eight sleep laboratory and 21 clinical studies on temazepam indicate that temazepam reduces awakening during the night and increases sleep duration. However, there was no consistent evidence that temazepam reduces sleep latency — probably because temazepam, taken at bedtime, does not reach sufficiently high blood levels in time to affect sleep onset. One sleep laboratory study on 8 insomniac patients given 35 consecutive nightly doses of 30 mg found no evidence of tolerance or rebound insomnia. Studies on tolerance, metabolism and carry‐over effects have shown that temazepam has no long‐acting metabolites and does not affect waking function following use at bedtime. In patients for whom hypnotic medication is appropriate, temazepam should be an effective drug for reducing most symptoms of insomnia.
Amdinocillin: A Novel Penicillin; Antibacterial Activity, Pharmacology and Clinical Use
Authors: Neu Harold C.
Published: December 2015

Amdinocillin is a novel penicillin whose antibacterial activity is derived from its ability to bind specifically and avidly to Penicillin Binding Protein‐2 (PBP 2). Other β‐lactams bind almost exclusively to PBPs 1 and 3. This unique feature has prompted many investigators to predict that amdinocillin would aggressively synergize with other antimicrobials, particularly other β‐lactams. Certain features of these predictions have been realized.

Amdinocillin is active alone against many gram‐negative organisms. Pseudomonas and non‐fermenting gram‐negative bacteria, however, are usually resistant. Amdinocillin, in combination with many β‐lactams, exhibits marked synergy against many enterobacteriaceae. No such synergy can be demonstrated for gram‐positive organisms or pseudomonas species. Amdinocillin is not β‐lactamase stable. Organisms which produce high levels of plasma‐mediated β‐lactamase are resistant to the drug.

Amdinocillin is widely distributed to most tissues of the body. It is removed by renal tubular secretion which results in prodigious levels of the drug in the urine. Coadministration of probenecid results in markedly elevated plasma levels of amidinocillin and delays its excretion. Amdinocillin has a plasma half‐life of about one hour in patients with grossly normal renal function. Its half‐life increases to 3 to 6 hours in anephric patients. The spectrum of adverse reactions observed with amdinocillin is similar to that of other penicillins.

Amdinocillin, as a single agent, is effective in the treatment of urinary tract infections caused by susceptible strains of E. coli and klebsiella and enterobacter species. When amdinocillin is used in concert with other antimicrobials, synergy can frequently be demonstrated but it is essentially limited to gram‐negative aerobic organisms. At present, insufficient data are available to precisely profile the utility of amdinocillin, either alone or in combination, in the treatment of systemic infections.
Adrenal Corticosteroids as Antiemetics During Cancer Chemotherapy
Authors: Cersosimo Robert J. , Karp Daniel D.
Published: December 2015

Adrenal corticosteroids were first reported in 1979 to have antiemetic effects during cancer chemotherapy. Since then considerable numbers of trials have been conducted to evaluate their activity alone and in combination with other agents. The majority of the research has centered on dexamethasone, although other corticosteroids have been studied. Dexamethasone as a single agent is superior to placebo and appears to be more effective than standard doses of prochlorperazine when administered with highly emetic agents. Dexamethasone is comparable to metoclopramide against moderately emetogenic agents and low‐dose cisplatin, but less effective than metoclopramide against highly emetic agents or high‐dose cisplatin. Dexamethasone improves the activity of prochlorperazine and metoclopramide and may reduce some of the side effects associated with the latter. Current trials continue to explore the role of corticosteroids alone and in combination with antiemetics.
Amikacin Pharmacokinetics in Patients with Spinal Cord Injury
Authors: Segal Jack L. , Brunnemann Sherry R. , Gordon Stanley K. , Eltorai Ibrahim M.
Published: December 2015

The influence of chronic (> 1 yr duration) spinal cord injury (SCI) on the disposition of amikacin was studied in seven healthy subjects with SCI (five paraplegic, two tetraplegic) and seven able‐bodied controls (intact neuraxes). The time course of amikacin serum concentration after a 30‐minute infusion (7.5 mg/kg) was followed for up to 8.5 hours using fluorescence polarization immunoassay. Pharmacokinetic values were estimated by a noncompartmental analysis (NC). Amikacin steady‐state volume of distribution (Vss) was increased to 0.20 ± 0.04 l/kg (mean ± SD) as compared to 0.17 ± 0.02 l/kg in able‐bodied controls (p 0.03), and its mean terminal elimination half‐life in patients with SCI was prolonged by 0.64 hours over the control value of 2.11 ± 0.27 hours (p 0.01). The NC estimated mean residence time (MRT) in patients with SCI (3.65 ± 0.75 hrs) was 0.89 hours longer than that observed in controls (p 0.03). Our data suggest that the Vss, half‐life, and MRT of amikacin are increased in persons with chronic SCI. As a result, amikacin dosing regimens developed in able‐bodied humans may demonstrate diminished efficacy when extrapolated uncritically to these patients.
An Evaluation of Flurbiprofen, Aspirin, and Placebo in Postoperative Oral Surgery Pain
Authors: Forbes James A. , Yorio Christine C. , Selinger Lawrence R. , Rosenmertz Stanley K. , Beaver William T.
Published: December 2015

One hundred sixty‐four outpatients with postoperative pain after the removal of impacted third molars were randomly assigned, on a double‐blind basis, to receive oral doses of flurbiprofen 25, 50, or 100 mg; aspirin 600 mg; or placebo. Using a self‐rating record, subjects rated their pain and its relief hourly for 8 hours after medicating. Estimates of sum of pain differences (SPID), peak pain intensity difference (PID), total relief, peak relief, and hours of 50% relief were derived from these subjective reports. All active medications were significantly superior to placebo. Analgesia was similar for flurbiprofen 25 mg and aspirin 600 mg. Flurbiprofen 50 and 100 mg were significantly superior to aspirin for every measure of analgesia except peak PID. There was a significant dose‐response regression between flurbiprofen 25 mg and both of the higher dosages. Flurbiprofen 50 and 100 mg did not differ significantly, suggesting a plateau in flurbiprofen's analgesia. The analgesic effect of flurbiprofen was significant by hour 1 and persisted for 8 hours. The frequency of adverse effects was similar for the active medications.
Use of a Trypsin, Peru Balsam, and Castor Oil Spray on the Oral Mucosa: Case Report and Review of the Literature
Authors: Noble Teresa A. , Carr Donna S. , Gonzalez M. Francisco
Published: December 2015

Granulex is an aerosolized spray (Dow B. Hickman Pharmaceuticals, Sugar Land, TX 77487) that contains trypsin, Peru balsam, and castor oil. It has been available for many years as a topical spray for the treatment of decubitus ulcers. We used Granulex to promote tissue healing of a necrotic ulcer of the oral mucosa in a patient with advanced oropharyngeal squamous cell carcinoma.
On the Mechanism for Flow in the Efferent Ducts
Authors: WINET HOWARD
Published: December 2015

A cilio‐peristaltic model for pumping of efferent duct (ED) contents that predicts the observed volumetric flow rates and is consistent with a positive pressure gradient toward the epididymis is proposed. The model predicts that the major contributor to fluid flow is the peristaltic component. The cilia, in contrast, may reduce flow by creating reflux. This effect may be reduced considerably with an increase in fluid viscosity, which is in turn a function of sperm concentration. It is concluded from this investigation that if the peristaltic wave has a 33% or more constriction, the spermatozoan concentration in the ED is at least 4 × 108 cells cm−3 and flow rates in the ED are the same as in the rete testis; then transit in the ED is due to cilio‐peristaltic pumping.
Ultrastructure and Maturational Changes in Spermatozoa in the Epididymis of the Pigtailed Monkey, Macaca nemestrina
Authors: HOFFER ANITA P. , SHALEV MOSHE , FRISCH DAVID H.
Published: December 2015

Ultrastructural characteristics of the acrosome, postacrosomal region, plasma membrane, and cytoplasmic droplet in spermatozoa taken from the caput, corpus, and cauda epididymidis of the pigtailed macaque are described. The subdivision of the postacrosomal region into an anterior and a posterior segment is demonstrated. Maturational changes manifest in the caudal shift of the cytoplasmic droplet and swelling of the plasma membrane are observed during epididymal transit in this species and are similar to those reported for other monkeys. However, the changes in the rostral segment of the acrosome are more striking than any in other Old World monkeys studied to date. In the caput epididymidis, the acrosome is asymmetric because its apical segment extends well beyond the rostral edge of the nucleus and folds under it, giving the acrosome a small but distinct hook shape In sagittal section. In the corpus and cauda, the acrosome contracts down over the nucleus, resulting in the loss of the asymmetry of the contours of the sperm head, and the distinctive hook‐shaped apical segment of the acrosome is no longer seen in sagittal section. On the basis of these findings, the pigtailed macaque appears to be a suitable primate model for morphologic analysis of structural variables during epididymal sperm maturation.
Validation of a Direct Radioimmunoassay for Testosterone in Unextracted Serum from Five Species: Application to Study of the Hypothalamic‐Pituitary‐Gonadal Axis in Males
Authors: SCHANBACHER B. D. , D'OCCHIO M. J.
Published: December 2015

A method for the radioimmunoassay of serum testosterone that does not require extraction or chromatography is described. Utilization of a highly specific antiserum, tritium‐labeled ligand, and double antibody precipitation makes the direct radioimmunoassay feasible. The direct radioimmunoassay is valid based on the criteria of sensitivity, specificity, accuracy, and precision. Because extraction, chromatography, and transfer are eliminated in this procedure, recovery of serum testosterone is always 100%. Interference by serum binding components is lacking, and values obtained for ram, bull, dog, rat, and man by direct radioimmunoassay are in agreement with those obtained by a conventional extraction assay.

Direct testosterone radioimmunoassay has been applied to the study of hypothalamic control of testosterone secretion in bull, ram, and rat. The intravenous injection of synthetic luteinizing hormone releasing hormone (LHRH) increases blood testosterone and can be administered to mimic the pulsatile nature of testosterone secretion characteristic of intact males. On the other hand, immunoneutralization of LHRH by active or passive immunization results in substantially reduced serum testosterone and failure of testosterone secretion in response to exogenous LHRH. These investigations lead us to conclude that testosterone secretion by the mammalian testis is regulated largely by inputs from the hypothalamus and that synthetic LHRH and LHRH antisera provide useful tools for studying the hypothalamopituitary‐gonadal axis. The direct radioimmunoassay provides a convenient and inexpensive method to study testosterone secretion by the testis.
Low‐molecular‐weight Inhibin from Sheep, Human, Rat, and Chicken Testes
Authors: BANDIVDEKAR ATMARAM H. , VIJAYALAKSHMI S. , MOODBIDRI SUDHIR B. , SHETH ANIL R.
Published: December 2015

Low‐molecular‐weight peptides with inhibin activity have been isolated from sheep, human, rat, and chicken testes by simple gel filtration. These peptides, isolated from avian and mammalian species, suppressed the postcastration rise of serum FSH levels in adult male rats by 34 to 45% and appeared to be biologically and chromatographically similar.
A Competitive In Vitro Assay of Human Sperm Fertilizing Ability Utilizing Contrasting Fluorescent Sperm Markers
Authors: BLAZAK W. F. , OVERSTREET J. W. , KATZ D. F. , HANSON F. W.
Published: December 2015

Fluorescein isothiocyanate (FITC) and tetramethyl rhodamine isothiocyanate (TRITC) were evaluated for use as contrasting fluorescent labels on living human spermatozoa. Unlabeled (control), FITC‐labeled (green fluorescence), TRITC‐labeled (red fluorescence), and mixed FITC‐TRITC‐labeled sperm suspensions were incubated with non‐fertilizable human oocytes for assessing sperm penetration of the zona pellucida and with zona‐free hamster eggs for assessing sperm incorporation into the ooplasm. Fluorochrome‐labeled spermatozoa were as efficient as unlabeled cells from the same donors in penetrating the human zona pellucida and in entering the hamster ooplasm. The middle and principal pieces of spermatozoa undergoing nuclear decondensation within the hamster ooplasm retained their fluorescent label, allowing visual differentiation between FITCand TRITC‐labeled spermatozoa. Videomicrographic analyses of the movement characteristics (percentage of motile cells and mean swimming speeds) of labeled and unlabeled spermatozoa before and after incubation with ova revealed no detrimental effect on the motility of labeled cells. We conclude that the fluorescent dyes FITC and TRITC do not impair the function of human spermatozoa as assessed by motility characteristics and by their ability to penetrate ova in vitro. The contrasting colors of the two fluorochromes make them particularly useful in the competitive assessment of the in vitro fertilizing potential of human spermatozoa from different donors or after different experimental treatments.
Quantitative Changes of Endogenous Unconjugated and Sulfated Steroids in Human Testis in Relation to Synthesis of Testosterone In Vitro
Authors: RUOKONEN AIMO O. , VIHKO REIJO K.
Published: December 2015

In order to investigate the function of steroid sulfates in human testicular steroid metabolism, the quantitative changes of endogenous steroids in testis tissue were characterized after synthesis of testosterone in vitro. The influence of an added substrate, dehydroepiandrosterone, was also studied. Unconjugated testosterone was the main steroid synthesized in all incubations.

In incubations without added substrate, hydrolysis of pregnenolone sulfate was the most intensive, followed by that of dehydroepiandrosterone sulfate. Concentrations of 5‐androstene‐3β,17β‐diol sulfate remained unchanged, whereas accumulating testosterone was significantly converted to its sulfate conjugate. Concentrations of pregnenolone, progesterone, and 17‐hydroxyprogesterone remained unchanged and those of dehydroepiandrosterone were increased.

At the concentrations used, addition of dehydroepiandrosterone significantly inhibited hydrolysis of dehydroepiandrosterone sulfate and increased the synthesis of 5‐androstene‐3β,17β‐diol sulfate. Testosterone synthesis further increased in all incubations, but concentrations of the other steroids investigated remained unchanged.

Quantitative results indicate that a considerable amount of testosterone was synthesized from steroid sulfates. Under conditions favoring testosterone formation, this active androgen was partly converted into its sulfate conjugate. These results further strengthen the concept that steroid sulfates have a dynamic role in testicular steroidogenesis in man.
The Male Antifertility Agents Alpha Chlorohydrin, 5‐Thio‐D‐Glucose, and 6‐Chloro‐6‐Deoxy‐D‐Glucose Interfere with Sugar Transport Across the Epithelium of the Rat Caput Epididymidis
Authors: HINTON BARRY T. , HERNANDEZ HERMAN , HOWARDS STUART S.
Published: December 2015

The effects of the male antif ertility agents α‐chlorohy‐drin, 5‐thio‐D‐glucose, and 6‐chloro‐6‐deoxy‐D‐glucose on sugar transport (3H‐3‐0‐methyl‐D‐glucose and 3H‐2‐deoxy‐D‐glucose) across the rat caput epithelium was studied in vivo and in vitro. The compound α chlorohydrin reduced sugar transport uptake in vivo but not in vitro whereas 5‐thio‐D‐glucose and 6‐chloro‐6‐deoxy‐D‐glucose were both effective in vivo and in vitro. The mechanism of action of these compounds on sugar movement across the caput epithelium is probably complex. Direct competition for the glucose carrier situated on the basolateral membrane and intratubular effects are suggested. Thirty‐day injections of 5‐thio‐D‐glucose or α‐chlorohydrin did not have adverse effects on sugar transport or the permeability of the blood‐testis and blood‐epididymis barriers as assessed by an in vitro technique.
The Aging Leydig Cell VIII Protein Kinase Activity
Authors: LIN TU , VINSON NANCY E. , MURONO EISUKE P. , OSTERMAN JURAJ , NANKIN HOWARD R.
Published: December 2015

The effects of aging on cyclic AMP (cAMP) dependent protein kinase activity of purified Leydig cells were evaluated. Purified Leydig cells from 20‐day‐, 40‐day‐, 60‐day‐ and 30‐month‐old rats were incubated with or without hCG for 1 hour. At the end of incubation, tubes were centrifuged and supernatants were saved for cAMP and testosterone determinations, and the pellets were prepared for protein kinase assay. Basal cAMP levels of Leydig cells from 20‐day‐ and 40‐day‐old rats were lower than those of 60‐day‐ and 30‐month‐old rats. In response to hCG stimulation, Leydig cells of 40‐day‐old rats produced the highest amounts of cAMP, while 30‐month‐old rats had the lowest levels. Testosterone responses of 30‐month‐old rats were also significantly lower than those of 60‐day‐old mature rats. When cAMP‐dependent protein kinase activities were measured, 30‐month‐old rats had the lowest total kinase activity. These results suggest that reduced protein kinase activity might contribute to the decreased testosterone synthesis of aged rats.
Effects of Long‐ and Short‐term Vasectomy on Structural and Functional Parameters of the Rat
Authors: MILLER ROMAN J. , KILLIAN GARY J. , VASILENKO PETER
Published: December 2015

The effects of vasectomy were examined by comparing various parameters from sham operated and vasectomized rats that had undergone surgery at 90 days of age and were killed at 190 or 390 days of age. Significant alterations in the vasectomized rats from sham rats included: testicular and epididymal hypertrophy, formation of pathologic vas deferens granulomas, decreased total serum protein, lowered alpha‐globulin levels as shown by serum electrophoresis, and increased sperm agglutinin antibody titers. For vasectomized rats, the differential white blood cell count showed increased numbers of neutrophils and large lymphocytes and decreased numbers of small lymphocytes and basophils. Both the number and extent of many vasectomy‐induced alterations were greater in long‐term vasectomized than in short‐term vasectomized rats.
Regulation of Rat Caput Epididymidis Contractility by Prostaglandins
Authors: COSENTINO M. JAMES , TAKIHARA HIROSHI , BURHOP JAMES W. , COCKETT ABRAHAM T. K.
Published: December 2015

Mechanical activity of the rat caput epididymidis in vitro was recorded using a videomicrography system. The effects of prostaglandin (PG)F2α, PGE2, and aspirin on caput epididymidis contractility were determined by measuring the frequency of contraction, luminal diameter, and amplitude of contraction at various concentrations of each test compound in vitro. PGF2α stimulated contractility of the tubules at physiological concentrations, while PGE2 reduced contractility. Aspirin strongly inhibited contractility at concentrations of 10−3 and 10−2 M. Endogenous levels of PGF2α and PGE were determined for rat testes, caput, corpus, and cauda epididymidis and vas deferens. While the concentrations of PGE were consistently higher than those of PGF2α, both compounds were relatively low in the testes, high in the vas deferens, and intermediate throughout the epididymis. Results from these experiments strongly suggest that PGs are important regulators of proximal epididymidis contractions and thus may regulate sperm transport through that organ.
Selective Luminal Absorption of L‐Carnitine from the Proximal Regions of the Rat Epididymis Possible Relationships to Development of Sperm Motility
Authors: HINTON B.T. , HERNANDEZ H.
Published: December 2015

The absorption of L‐carnitine from the duct of the proximal regions of the rat epididymis was investigated using a stopped‐flow, split‐droplet microperfusion technique. L‐carnitine was absorbed from the duct of the proximal caput epididymidis by a time‐dependent and saturable transport system (Km = 25 μm; Vmax = 0.65 pmoles absorbed/min/mm3 tubular volume). Furthermore, absorption appeared to be primarily sodium‐independent, although the existence of a minor sodium‐dependent pathway cannot be ruled out. A similar transport system was not evident along the distal caput epididymidis, where absorption of L‐carnitine was attributable to passive diffusion only. The inward and outward movement of L‐carnitine across the epithelium of the proximal and distal caput epididymidis appears to be regulated so that the spermatozoa come into contact with high levels of L‐carnitine in the distal caput region.
Sex Steroid‐induced Changes in Collagen of the Prostate and Seminal Vesicle of Rats
Authors: SRINIVASAN N. , ARULDHAS M. MICHAEL , GOVINDARAJULU P.
Published: December 2015

The effects of androgens alone or in combination with estrogen or prolactin on the collagen of the prostate and seminal vesicles were studied in prepubertal and adult rats. Castration decreased the collagen content of the male accessory sex organs of both prepubertal and adult rats. Androgens showed stimulatory effects in castrated rats irrespective of the age. However, in intact animals, the stimulatory effects of androgens were evident only before puberty. Only the seminal vesicle of prepubertal rats responded to the stimulatory effect of estrogen given along with androgens. Prolactin did not elicit any appreciable effect either in the prostate or the seminal vesicles when administered along with androgens.
Correlation Between Defective Motility (Asthenospermia) and ATP Reactivation of Demembranated Human Spermatozoa
Authors: LIU DE YI , JENNINGS M. GAEL , BAKER H.W. GORDON
Published: December 2015

Human spermatozoa treated with 0.05% Triton X‐100 to remove the cell membranes became immotile but flagellar movement was reinitiated by addition of 0.06 to 1 mM adenosine triphosphate (ATP). The percentage of spermatozoa showing flagellar movement 2 minutes after addition of 1 mM ATP from men with idiopathic asthenospermia (mean ± SD, 34 ± 15%), oligozoospermia (17 ± 21%), sperm autoimmunity (17 ± 12%), vasoepididymostomy (20 ± 22%), or idiopathic zero motility (0%) was significantly lower than with spermatozoa from normal men (54 ± 12%). The percentage of reactivated spermatozoa was correlated with the proportion of live cells (Eosin Y stain, r = 0.602, P < 0.001), percentage of motile cells (r = 0.761, P < 0.001), and motility index (r = 0.759, P < 0.001) in the same semen samples. When expressed relative to initial sperm motility, the proportion reactivated was similar for idiopathic asthenospermia (85%) and normospermia (82%). Thus, failure to produce ATP does not appear to be a frequent cause of low sperm motility in man.
Pituitary—Testicular Function of Prostatic Cancer Patients During Treatment with a Gonadotropin‐Releasing Hormone Agonist Analog I. Circulating Hormone Levels
Authors: HUHTANIEMI I. , NIKULA H. , RANNIKKO S.
Published: December 2015

Eight patients with advanced prostatic carcinoma (ages 59 to 78 years) were treated with a potent gonadotropin‐releasing hormone (GnRH) agonist analog (buserelin, Hoechst; 600 μg intranasally, 3 times daily) and orchiectomized after 6 months of treatment. Endocrine responses were followed by serum hormone measurements during agonist treatment and for 3 months after orchiectomy. Six other patients (65 to 86 years) with advanced prostatic cancer had been orchiectomized as the first therapeutic measure and their blood samples were used as controls. In the GnRH agonist‐treated patients, serum immunoreactive luteinizing hormone (LH) and follicle stimulating hormone (FSH) decreased after initial stimulation by 70 to 80%, within 1 to 3 weeks (P < 0.01). FSH partly recovered (P < 0.05) after the first month of treatment. Serum prolactin (PRL) displayed a slight tendency to decline during buserelin treatment (P < 0.05). Serum total and free testosterone (T) of the buserelin‐treated patients decreased to the castrate range within 3 to 4 weeks after an initial 5‐day increase (P < 0.01). Serum progesterone and 17‐hydroxyprogesterone (17‐OHP‐4) decreased to the castrate range (by 50 to 70%) in 1 week. Only minor changes were observed in sex hormone binding globulin (SHBG). Significant, acute elevations of LH, FSH, T, and 17‐OHP‐4 were observed only on day 1 after an injection of buserelin (500 μg i.m.) and not when assessed between day 7 and month 6 of treatment. After 6 months of buserelin treatment, orchiectomy did not affect the serum steroids measured. After orchiectomy, immediate increases in serum LH, and somewhat later in FSH, were seen in the control patients. Initial treatment with buserelin did not affect the postcastration rise of FSH, whereas the rise of LH was delayed by about 2 weeks. In summary, these results indicate that pituitary‐ testicular function becomes refractory to stimulation of high‐dose buserelin treatment within a week. Testicular steroids decrease to the castrate range within 3 to 4 weeks, probably through inhibition of steroidogenesis proximally to progesterone and 17‐OHP‐4 formation. After simultaneous cessation of treatment and surgical castration, the desensitization of the pituitary applies only to LH secretion, whereas the postcastration rise of FSH is essentially similar to that of orchiectomized control patients.
Further Characterization of a Secreted Epididymal Glycoprotein in Mice that Binds to Sperm Tails
Authors: VERNON ROBERT B. , MULLER CHARLES H. , EDDY E. M.
Published: December 2015

Sperm maturation antigen 4 (SMA‐4) is a surface component of the mouse sperm tail. Previously, immunofluorescence studies indicated that SMA‐4 may be secreted by principal cells of the distal caput epididymidis and bound to spermatozoa as they pass through that region of the duct. In the present study, detergent extracts of spermatozoa from the cauda epididymidis were subjected to polyacrylamide gel electrophoresis under reducing and denaturing conditions, transferred to nitrocellulose, and immunostained with a monoclonal antibody against SMA‐4. A band of approximately 54,000 molecular weight was revealed. The band was also stained by the periodic acid‐Schiff (PAS) procedure. This glycoprotein was not detected in extracts of spermatozoa from the proximal caput epididymidis or of spermatozoa from the cauda epididymidis that were preincubated for 4 hours in an in vitro fertilization environment. Blots of sperm‐free fluid from the corpus and cauda epididymidis displayed an immunoreactive and PAS‐positive band of about 85,000 molecular weight that was not observed in fluid from the caput epididymidis. The difference in the molecular weights of the antigen in the fluid and that in extracts of cauda spermatozoa suggests that SMA‐4 may be modified chemically upon association with the sperm surface.
Inhibin Production by Sertoli Cells During Testicular Regression in the Golden Hamster
Authors: BERKOWITZ ALBERT S. , HEINDEL JERROLD J.
Published: December 2015

The objective of this study was to determine if testicular regression in the hamster results in changes in Sertoli cell function that reflect altered pituitary function. Inhibin‐like activity was measured in spent media from Sertoli cells cultured from adult control and optically enucleated hamsters with regressed testes using a homologous hamster Sertoli cell/hamster pituitary cell bioassay. The inhibin activity resulted in a dose‐related decrease in FSH release from both normal and “regressed” pituitary cultures but maximal inhibition occurred at a 3‐ to 4‐fold lower dose with media from Sertoli cells obtained from regressed hamsters. When pituitary cells from control adult or adult hamsters with regressed testes were incubated with Sertoli cell spent media, pituitary cells from regressed hamsters were more sensitive than normal pituitary cells to both normal and “regressed” inhibin. This greater production of inhibin‐like activity and/or an enhanced sensitivity to inhibin in the regressed hamster may contribute to the decline in FSH levels during testicular regression. This data lends further support to a physiologic role for inhibin.
Morphologic Changes Induced by Short‐term Ischemia in the Rat Testis Are Not Affected by Treatment with Superoxide Dismutase and Catalase
Authors: BERGH ANDERS , DAMBER JAN‐ERIK , MARKLUND STEFAN L.
Published: December 2015

Short‐term testicular ischemia was induced unilaterally by ligating the testicular artery for 60 or 100 minutes in adult rats. After 7 days, the rats were fixed by vascular perfusion. The effect of ischemia and reperfusion was quantified using morphometric techniques. Occlusion of the testicular artery for 60 and 100 minutes resulted in a mild and moderate damage, respectively, to the seminiferous tubules. The contralateral control testis was not affected. To study the role of oxygen radicals in ischemia‐reperfusion‐induced testicular damage, rats were treated with superoxide dismutase and catalase. These radical scavengers did not influence the extent of testicular damage.
Physiologic Attributes of the Luteinizing Hormone Pulse Signal in the Human Cross‐Validation Studies in Men
Authors: VELDHUIS JOHANNES D. , EVANS WILLIAM S. , URBAN RANDALL J. , ROGOL ALAN D. , JOHNSON MICHAEL L.
Published: December 2015

The performance of two new statistically based, independently formulated, endocrine peak detection methodologies (Cluster and Detect) were tested on the same large set of physiologic LH pulsations. Serum LH concentrations were determined in blood samples withdrawn at 5‐minute intervals for 24 hours in eight healthy young men. The subsequent comprehensive LH time series were subjected to Cluster and Detect analysis, each constrained to an alpha level of 0.01 or 0.05. Under both circumstances, computer estimates of physiologic LH pulse frequency by the two separate algorithms were statistically indistinguishable. Moreover, the two distinct methodologies were concordant not only in relation to the original 5‐minute sampling series but also with respect to the constituent 10‐, 15‐, 20‐, 30‐, and 45‐minute sampling data. The cross‐validation of these two mathematically independent methodologies has permitted delineation of the detailed spectrum of spontaneous LH pulse properties within individual men and among different males under basal physiologic conditions.
Kinetics of Secretion of Luteinizing Hormone Subunits and Free Alpha, and Effects of Gonadotropin Releasing Hormone
Authors: VOGEL DONNA L. , ROWLAND JACK A. , SHERINS RICHARD J.
Published: December 2015

While GnRH is known to stimulate release of pituitary gonadotropins, its acute effects on the kinetics of secretion of the various hormones and subunits are not well characterized. Pulse‐chase experiments were therefore performed to compare the time course of secretion of newly synthesized LH subunits and free α from rat pituitary quarters, and to study the effects of GnRH. After a l‐h pulse labeling with [35S]cysteine in the presence or absence of 10−8 M GnRH, cultures were chased with excess unlabeled cysteine for 1, 2, 4, 8, or 20 h. Tissue lysates and media were immunoprecipitated sequentially with antisera to PRL, GH, LHβ and LHα, and the products were analyzed by gel electrophoresis.

Labeled LHα was completely secreted by 4 h of chase without GnRH, and by 2 h with GnRH, as shown by its appearance in media and depletion from pituitary. Newly synthesized LHβ was depleted only at 8 h with GnRH from pituitary, suggesting much slower secretion. Incorporation of 35S into LHβ was approximately half that into LHα. Newly synthesized free α subunit was secreted between 4 and 20 h without GnRH, and by 8 h with GnRH. Free α incorporated a similar amount of radioactivity as LHβ.

GnRH had no effect on the timing of the secretion of labeled total protein, PRL, GH, or TSH subunits. The amount of label incorporated during the pulse was greatest for PRL, approximately 15% of total protein label. GH incorporated approximately 20% as much label as PRL, with the glycoprotein subunits somewhat lower.

The total amount of 35S incorporated into each protein studied was not affected by GnRH.

The data indicate that short term in vitro GnRH exposure during a 1‐h pulse labeling and chase acts to accelerate early secretion of LHα, LHβ and free α but does not affect overall protein synthesis. The peptide hormones PRL and GH incorporated the greatest amount of label and were the most briskly secreted hormones, while LHα led the glycoprotein subunits in the amount of incorporation and rapidity of secretion.
Age‐Related Changes in the Concentration of Cytosolic Androgen Receptors in the Epididymis, Vas Deferens and Seminal Vesicle of Maturing Male Mice
Authors: Ch. GALLON  , VEYSSIERE G. , BERGER M. , Ch. JEAN‐FAUCHER  , De TURCKHEIM M. , Cl. JEAN
Published: December 2015

In this study, changes in the number of androgen binding sites that occur in cytosols of epididymis, vas deferens and seminal vesicle of mice from 10 to 90 days of age are described. Specific saturable binding of [3H]R‐1881 by cytosols of the three organs at all time points studied and age‐related differences in the number of binding sites measured were observed. Cytosolic androgen receptor levels in all three organs studied were found to decrease with increasing age, regardless of whether the binding was expressed relative to weight of tissue, cytosolic protein or cellular DNA. The most pronounced change in androgen receptor levels (from 442 to 50 fmol/mg protein) was observed in the epididymis between 10 and 30 days of age. In these three organs there was no significant correlation between androgen (testosterone + dihydrotestosterone) levels and the concentration of androgen binding sites.
Apparent Fertility of Human Spermatozoa from the Caput Epididymidis
Authors: SILBER SHERMAN J.
Published: December 2015

Fifty‐one patients with obstructive azoospermia caused by blockage at the caput epididymidis have been followed for 4 years after undergoing “specific tubule” vasoepididymostomy, bypassing the corpus and cauda. The patency rate was 73%, and the pregnancy rate was 31%. There was no correlation between sperm count and pregnancy rate, but there was a strong correlation with sperm motility. With < 20% motility, only 15% of the patients became pregnant, but with > 20% motility postoperatively, 58% became pregnant. If the wife was over 30 years old, only 21% got pregnant. If the wife was under 30, 67% got pregnant. “Redo” cases were just as likely to succeed as “first‐time” attempts. In the “patent” cases, 43% of patients with spermatozoa that never reached or traversed the corpus or cauda epididymidis produced a pregnancy. Spermatozoa from the proximal caput produced a 33% pregnancy rate, whereas spermatozoa from the distal caput produced a 50% pregnancy rate. One‐half of the pregnancies occurred more than 2 years postoperatively.
Identification of Androgen Binding‐Protein (ABP) From Testis and Epididymis of the Seasonal Rodent, Octodon degus (Molina, 1872)
Authors: BALBONTIN JUAN B. , BUSTOS‐OBREGON EDUARDO
Published: December 2015

ABP, a Sertoli cell secretory product, was identified in the seasonal rodent Octodon degus (Molina, 1872). It was shown to be present in cytosols from the testis and epididymis. It migrated with an Rf of 0.37 on nonde‐naturing polyacrylamide gels. Ligation of the vas efferens caused the disappearance of ABP from the epididymis and its accumulation in the testis, indicating its testicular origin. Binding to [3H]5α‐DHT was specific and completely reversible, with an apparent Kd of 3.5 ± 0.4 × 10−9 M. Half‐times of association and dissociation were at 15 and 120 minutes, respectively. Binding equilibrium was achieved at 120 minutes. Steroid affinity relative to the best competitor, 5α‐DHT, was 0.27 for testosterone, 0.06 for 170β‐estradiol, and 0.01 for cyproterone acetate. The presence and similar characteristics of ABP in a wide variety of mammals, including those with special reproductive strategies such as seasonal breeding, suggests that this protein may play a general role in the mechanisms regulating spermatogenesis, probably affecting the transport and concentration of androgens in the testis and epididymis.
The Action of Calcitonin on the TM4 Sertoli Cell Line and on Rat Sertoli Cell‐Enriched Cultures
Authors: NAKHLA ATIF M. , MATHER JENNIE P. , JÄNNE OLLI A. , BARDIN C. WAYNE
Published: December 2015

The effects of synthetic salmon calcitonin on primary Sertoli cell‐enriched cultures and on an established cell line (TM4 cells, derived from immature mouse Sertoli cells) were studied. Synthetic salmon calcitonin stimulated the conversion of [3H]adenine to [3H]cyclic AMP in both cell systems. In addition, this peptide stimulated the secretion of rABP in primary Sertoli cellenriched cultures prepared from rat testis. Calcitonin also increased the total concentration of both androgen and estrogen receptors in TM4 cells. Because cAMP analogs decreased androgen and estrogen receptor concentrations, the effect of calcitonin on sex steroid receptors may not be mediated by its effect on cyclic AMP in these cells. The possibility that the action of synthetic salmon calcitonin on the receptors might be mediated by a change in cellular Ca2+ was investigated. Lowering extracellular Ca2+ concentrations from 1.5 mM to less than 0.01 mM markedly reduced the concentration of androgen and estrogen receptors; restoration of Ca2+ to 1.5 mM returned receptor levels to normal. When the receptor concentrations were decreased by lowering extracellular Ca2+ concentrations to 0.5 mM, treatment with the calcium ionophore, A23187, restored receptor levels to normal. Although the calcium channel blocker, verapamil, decreased receptor levels, calcitonin partially counteracted its effect. Trifluoperazine, an inhibitor of calmodulin, also diminished androgen and estrogen receptor levels in the cytosol of TM4 cells. It was concluded that calcitonin stimulates the formation of cyclic AMP and the secretion of rABP by Sertoli cells. This peptide also increases the concentration of androgen and estrogen receptors, possibly by a mechanism that is, in part, Ca2+‐mediated. These results, along with those on Leydig cells, suggest that calcitonin could be a regulator of testicular function.
Leydig Cell and Extracellular Matrix Effects on Sertoli Cell Function: Biochemical and Morphologic Studies
Authors: REVENTOS J. , PERRARD‐SAPORI M.H. , CHATELAIN P.G. , SAEZ J.M.
Published: December 2015

The reciprocal influence between Leydig and Sertoli cells prepared from pig testis were studied by coculture of both types of cells in either plastic dishes or dishes coated with basement membrane matrix. After 2–3 days in plastic dishes, Sertoli cells produced an increase in the steroidogenic response of Leydig cells to hCG. Pretreatment of the coculture with pFSH enhanced the steroidogenic capacity of Leydig cells and increased the number of hCG receptors. Similarly, the number of FSH binding sites and the FSH‐induced plasminogen activator activity secretion of Sertoli cells cocultured with Leydig cells were increased. Pretreatment of the coculture with hCG further enhanced both parameters. The positive reciprocal trophic effects between Leydig cells and Sertoli cells were significantly enhanced when the coculture was carried out on the top of extracellular matrix. In addition, when cells were cocultured under these conditions, but not on plastic dishes, they were organized in cell clusters or island structures, with most of the Leydig cells located in the outer area, whereas Sertoli cells were located inside the islands.
Identification of a Potential FSH Modulatory Protein in Human Testis and Seminal Plasma
Authors: SLUSS PATRICK M. , SCHNEYER ALAN L. , COCKETT ABRAHAM T.K. , CROMIE WILLIAM J.
Published: December 2015

A variety of factors capable of inhibiting the in vitro binding of FSH to its receptor have been identified in gonadal tissues from males and females. Interest in these factors has been stimulated because of their potential role as local modulators of gonadotropin action. Studies reported here were undertaken to determine if proteins having antigenic homologies with human FSH or an “FSH‐like” protein isolated from porcine follicular fluid were present in human testicular tissue or seminal plasma. Polyclonal antibodies were generated against fractions of porcine follicular fluid containing FSH receptor binding inhibitory activity, FSH agonist activity in vitro, and a 58,000 Mr protein recognized by human FSH antiserum. Antiserum against this fraction of porcine follicular fluid and antiserum against human FSH were used to probe Western blots of proteins from human testis homogenates or seminal plasma. A 58,000 Mr protein was identified in both human testis extract and seminal plasma. This protein appears to be related antigenically to both human FSH and the 58,000 Mr “FSH‐like” protein in porcine follicular fluid. It does not appear to be a metabolic degradatory product of human FSH since the protein is larger than FSH, does not dissociate into subunits under reducing conditions and is recognized by the antiserum to FSH‐like protein that does not recognize human FSH. These data identify a 58,000 Mr protein in human testis and seminal plasma that may represent a local modulator of FSH action in the testis.
Induction of Spermatogenesis by Recombinant Follicle‐Stimulating Hormone (Puregon) in Hypogonadotropic Azoospermic Men Who Failed to Respond to Human Chorionic Gonadotropin Alone
Authors: Bouloux Pierre‐Marc G. , Nieschlag Eberhard , Burger Henry G. , Skakkebaek Niels E. , Wu Frederick C.W. , Handelsman David J. , Baker Gordon H.W. , Ochsenkuehn Robert , Syska Annemarie , McLachlan Robert I. , Giwercman Aleksander , Conway Ann J. , Turner Leo , van Kuijk Jacqueline H.M. , Voortman Gerrit
Published: December 2015

ABSTRACT: A multicenter, open‐label, randomized efficacy and safety study was performed with combined human chorionic gonadotropin (hCG) and recombinant follicle‐stimulating hormone (recFSH) (Puregon®) treatment to induce spermatogenesis in hypogonadotropic hypogonadal male patients. Patients were pretreated for 16 weeks with hCG to normalize testosterone levels. A total of 30 of 49 (61%) subjects had normalized testosterone levels but were still azoospermic after the hCG‐alone phase. These patients were randomized into 2 treatment schemes with recFSH (2 × 225 IU recFSH per week [group A] or 3 × 150 IU recFSH per week [group B]), in combination with hCG for a period of 48 weeks. Total testosterone increased during the hCG‐alone period from 1.08 and 1.22 ng/mL to 6.26 and 4.52 ng/mL for groups A and B, respectively. Combined gonadotropin treatment was effective in inducing spermatogenesis (sperm count ≥1 × 106/mL) in 14 of 30 subjects (47%) and this was achieved after a median duration of treatment of approximately 5.5 months. Treatment time necessary for first sperm cells to appear in the ejaculate was related to the initial testicular volume. Subjects with a history of maldescended testes (11 of 30 subjects, 37%) showed a lower mean response to treatment as indicated by the relatively lower number of subjects reaching levels of at least 1 × 106 sperm cells per milliliter. Combined testicular volume increased during combined gonadotropin treatment from 11.4 to 24.0 mL. Although subjects with a history of maldescended testes had a lower starting testicular volume, subjects with and without a history of maldescended testes showed approximately the same relative increase in testicular volume. Total testosterone levels showed only a minor further increase during the combined gonadotropin treatment period. In conclusion, a weekly dose of 450 IU (3 × 150 IU or 2 × 225 IU) recFSH, in addition to hCG, was able to induce spermatogenesis in many hypogonadotropic azoospermic men who failed to respond to treatment with hCG alone.