Probing the distinct chemosensitivity of Plasmodium vivax liver stage parasites and demonstration of 8-aminoquinoline radical cure activity in vitro

Improved control of Plasmodium vivax malaria can be achieved with the discovery of new antimalarials with radical cure efficacy, including prevention of relapse caused by hypnozoites residing in the liver of patients. We screened several compound libraries against P. vivax liver stages, including 1565 compounds against mature hypnozoites, resulting in one drug-like and several probe-like hits useful for investigating hypnozoite biology. Primaquine and tafenoquine, administered in combination with chloroquine, are currently the only FDA-approved antimalarials for radical cure, yet their activity against mature P. vivax hypnozoites has not yet been demonstrated in vitro. By developing an extended assay, we show both drugs are individually hypnozonticidal and made more potent when partnered with chloroquine, similar to clinically relevant combinations. Post-hoc analyses of screening data revealed excellent performance of ionophore controls and the high quality of single point assays, demonstrating a platform able to support screening of greater compound numbers. A comparison of P. vivax liver stage activity data with that of the P. cynomolgi blood, P. falciparum blood, and P. berghei liver stages reveals overlap in schizonticidal but not hypnozonticidal activity, indicating that the delivery of new radical curative agents killing P. vivax hypnozoites requires an independent and focused drug development test cascade.

An adaptable soft-mold embossing process for fabricating optically-accessible, microfeature-based culture systems and application toward liver stage antimalarial compound testing

Advanced cell culture methods for modeling organ-level structure have been demonstrated to replicate in vivo conditions more accurately than traditional in vitro cell culture. Given that the liver is particularly important to human health, several advanced culture methods have been developed to experiment with liver disease states, including infection with Plasmodium parasites, the causative agent of malaria. These models have demonstrated that intrahepatic parasites require functionally stable hepatocytes to thrive and robust characterization of the parasite populations' response to investigational therapies is dependent on high-content and high-resolution imaging (HC/RI). We previously reported abiotic confinement extends the functional longevity of primary hepatocytes in a microfluidic platform and set out to instill confinement in a microtiter plate platform while maintaining optical accessibility for HC/RI; with an end-goal of producing an improved P. vivax liver stage culture model. We developed a novel fabrication process in which a PDMS soft mold embosses hepatocyte-confining microfeatures into polystyrene, resulting in microfeature-based hepatocyte confinement (μHEP) slides and plates. Our process was optimized to form both microfeatures and culture wells in a single embossing step, resulting in a 100 μm-thick bottom ideal for HC/RI, and was found inexpensively amendable to microfeature design changes. Microfeatures improved intrahepatic parasite infection rates and μHEP systems were used to reconfirm the activity of reference antimalarials in phenotypic dose-response assays. RNAseq of hepatocytes in μHEP systems demonstrated microfeatures sustain hepatic differentiation and function, suggesting broader utility for preclinical hepatic assays; while our tailorable embossing process could be repurposed for developing additional organ models.

Open-source discovery of chemical leads for next-generation chemoprotective antimalarials

To discover leads for next-generation chemoprotective antimalarial drugs,we tested more than 500,000 compounds for their ability to inhibit liver-stage development of luciferase-expressing Plasmodium spp. parasites (681 compounds showed a half-maximal inhibitory concentration of less than 1micromolar).Cluster analysis identified potent and previously unreported scaffold families as well as other series previously associated with chemoprophylaxis. Further testing through multiple phenotypic assays that predict stage-specific and multispecies antimalarial activity distinguished compound classes that are likely to provide symptomatic relief by reducing asexual blood-stage parasitemia from those which are likely to only prevent malaria. Target identification by using functional assays, in vitro evolution, or metabolic profiling revealed 58 mitochondrial inhibitors but also many chemotypes possibly with previously unidentified mechanisms of action.

A comprehensive model for assessment of liver stage therapies targeting Plasmodium vivax and Plasmodium falciparum

Malaria liver stages represent an ideal therapeutic target with a bottleneck in parasite load and reduced clinical symptoms; however, current in vitro pre-erythrocytic (PE) models for Plasmodium vivax and P. falciparum lack the efficiency necessary for rapid identification and effective evaluation of new vaccines and drugs, especially targeting late liver-stage development and hypnozoites. Herein we report the development of a 384-well plate culture system using commercially available materials, including cryopreserved primary human hepatocytes. Hepatocyte physiology is maintained for at least 30 days and supports development of P. vivax hypnozoites and complete maturation of P. vivax and P. falciparum schizonts. Our multimodal analysis in antimalarial therapeutic research identifies important PE inhibition mechanisms: immune antibodies against sporozoite surface proteins functionally inhibit liver stage development and ion homeostasis is essential for schizont and hypnozoite viability. This model can be implemented in laboratories in disease-endemic areas to accelerate vaccine and drug discovery research.

Microfluidic Biopsy Trapping Device for the Real-Time Monitoring of Tumor Microenvironment

The tumor microenvironment is composed of cellular and stromal components such as tumor cells, mesenchymal cells, immune cells, cancer associated fibroblasts and the supporting extracellular matrix. The tumor microenvironment provides crucial support for growth and progression of tumor cells and affects tumor response to therapeutic interventions. To better understand tumor biology and to develop effective cancer therapeutic agents it is important to develop preclinical platforms that can faithfully recapitulate the tumor microenvironment and the complex interaction between the tumor and its surrounding stromal elements. Drug studies performed in vitro with conventional two-dimensional cancer cell line models do not optimally represent clinical drug response as they lack true tumor heterogeneity and are often performed in static culture conditions lacking stromal tumor components that significantly influence the metabolic activity and proliferation of cells. Recent microfluidic approaches aim to overcome such obstacles with the use of cell lines derived in artificial three-dimensional supportive gels or micro-chambers. However, absence of a true tumor microenvironment and full interstitial flow, leads to less than optimal evaluation of tumor response to drug treatment. Here we report a continuous perfusion microfluidic device coupled with microscopy and image analysis for the assessment of drug effects on intact fresh tumor tissue. We have demonstrated that fine needle aspirate biopsies obtained from patient-derived xenograft models of adenocarcinoma of the lung can successfully be analyzed for their response to ex vivo drug treatment within this biopsy trapping microfluidic device, wherein a protein kinase C inhibitor, staurosporine, was used to assess tumor cell death as a proof of principle. This approach has the potential to study tumor tissue within its intact microenvironment to better understand tumor response to drug treatments and eventually to choose the most effective drug and drug combination for individual patients in a cost effective and timely manner.

Complications of injectable testosterone undecanoate in routine clinical practice

OBJECTIVE

Injectable testosterone undecanoate (TU) was marketed within the last decade, but its complications in routine clinical practice are not well defined.

DESIGN AND METHODS

Prospective observational study of consecutive TU injections in an Andrology Clinic to estimate the incidence of i) immediate cough/syncope due to pulmonary oil microembolisation (POME), ii) post-injection haematoma and iii) the prevalence of secondary polycythaemia.

RESULTS

In 3022 injections given to 347 patients over 3.5 years, POME was observed after 56 injections (66% mild, 19% severe; 40% with onset before injection completed) in 43 patients. The incidence of 19 (95% CI 14-24) per 1000 injections did not differ between three experienced nurse injectors, but recurrences were more frequent than by chance. No post-injection haematoma was reported including after 269 injections to men taking antiplatelet, anticoagulant or both drugs (upper 95% confidence limit 1%) with 56 not withholding drugs prior to TU administration (upper 95% confidence limit 5.4%). Mean haematocrit was 0.44±0.04 (s.d.) with 25 (7%) >0.50, 14 (4%) >0.52 and 3 (1%) >0.54.

CONCLUSION

TU injections produce a low incidence of POME with injections by experienced nurses, but recurrence is more frequent than by chance. Post-injection haematoma was not observed even among men using anticoagulant and/or antiplatelet drugs, and polycythaemia was a minor problem rarely requiring treatment other than optimising inter-injection interval.

Dispersion of a Nanoliter Bolus in Microfluidic Co-Flow

Microfluidic systems enable reactions and assays on the scale of nanoliters. However, at this scale nonuniformities in sample delivery become significant. To determine the fundamental minimum sample volume required for a particular device, a detailed understanding of mass transport is required. Co-flowing laminar streams are widely used in many devices, but typically only in the steady-state. Because establishing the co-flow steady-state consumes excess sample volume and time, there is a benefit to operating devices in the transient state, which predominates as the volume of the co-flow reactor decreases. Analysis of the co-flow transient has been neglected thus far. In this work we describe the fabrication of a pneumatically controlled microfluidic injector constructed to inject a discrete 50nL bolus into one side of a two-stream co-flow reactor. Using dye for image analysis, injections were performed at a range of flow rates from 0.5-10μL/min, and for comparison we collected the co-flow steady-state data for this range. The results of the image analysis were also compared against theory and simulations for device validation. For evaluation, we established a metric that indicates how well the mass distribution in the bolus injection approximates steady-state co-flow. Using such analysis, transient-state injections can approximate steady-state conditions within predefined errors, allowing straight forward measurements to be performed with reduced reagent consumption.

Randomised controlled trial of whether erotic material is required for semen collection: impact of informed consent on outcome

Semen is collected to evaluate male fertility or cryostore sperm preferentially in laboratories but such collection facilities have no standard fit-out. It is widely believed but untested whether providing erotic material (EM) is required to collect semen by masturbation in the unfamiliar environment. To test this assumption, 1520 men (1046 undergoing fertility evaluation, 474 sperm cryostorage, providing 1932 semen collection episodes) consecutively attending the semen laboratory of a major metropolitan teaching hospital for semen analysis were eligible for randomization to be provided or not with printed erotic material EM (X-rated, soft-core magazines) during semen collection. Randomization was performed by providing magazines in the collection rooms (as a variation on non-standard fit-out) on alternate weeks using a schedule concealed from participants. In the pilot study, men were randomized without seeking consent. In the second part of the study, which continued on from the first without interruption, an approved informed consent procedure was added. The primary outcome, the time to collect semen defined as the time from receiving to returning the sample receptacle, was significantly longer (by ~6%, 14.9 ± 0.3 [mean ± standard error of mean] vs. 14.0 ± 0.2 minutes, p = 0.02) among men provided with EM than those randomized to not being provided. There was no significant increase in the failure to collect semen samples (2.6% overall) nor any difference in age, semen volume or sperm concentration, output or motility according to whether EM was provided or not. The significantly longer time to collect was evident in the pilot study and the study overall, but not in the main study where the informed consent procedure was used. This study provides evidence that refutes the assumption that EM needs to be provided for semen collection in a laboratory. It also provides an example of a usually unobservable participation bias influencing study outcome of a randomized controlled trials.

A modular approach to create a neurovascular unit-on-a-chip

In this work, we describe the fabrication and working of a modular microsystem that recapitulates the functions of the "Neurovascular Unit". The microdevice comprised a vertical stack of a poly(dimethylsiloxane) (PDMS) neural parenchymal chamber separated by a vascular channel via a microporous polycarbonate (PC) membrane. The neural chamber housed a mixture of neurons (~4%), astrocytes (~95%), and microglia (~1%). The vascular channel was lined with a layer of rat brain microvascular endothelial cell line (RBE4). Cellular components in the neural chamber and vascular channel showed viability (>90%). The neural cells fired inhibitory as well as excitatory potentials following 10 days of culture. The endothelial cells showed diluted-acetylated low density lipoprotein (dil-a-LDL) uptake, expressed von Willebrand factor (vWF) and zonula occludens (ZO-1) tight junctions, and showed decreased Alexafluor™-conjugated dextran leakage across their barriers significantly compared with controls (p < 0.05). When the vascular layer was stimulated with TNF-α for 6 h, about 75% of resident microglia and astrocytes on the neural side were activated significantly (p < 0.05 compared to controls) recapitulating tissue-mimetic responses resembling neuroinflammation. The impact of this microsystem lies in the fact that this biomimetic neurovascular platform might not only be harnessed for obtaining mechanistic insights for neurodegenerative disorders, but could also serve as a potential screening tool for central nervous system (CNS) therapeutics in toxicology and neuroinfectious diseases.

Effects of testosterone and nandrolone on cardiac function: a randomized, placebo-controlled study

BACKGROUND

Androgens have striking effects on skeletal muscle, but the effects on human cardiac muscle function are not well defined, neither has the role of metabolic activation (aromatization, 5alpha reduction) of testosterone on cardiac muscle been directly studied.

OBJECTIVE

To assess the effects of testosterone and nandrolone, a non-amplifiable and non-aromatizable pure androgen, on cardiac muscle function in healthy young men.

DESIGN

Double-blind, randomized, placebo-controlled, three-arm parallel group clinical trial.

SETTING

Ambulatory care research centre.

PARTICIPANTS

Healthy young men randomized into three groups of 10 men.

INTERVENTION

Weekly intramuscular injections of testosterone (200 mg mixed esters), nandrolone (200 mg nandrolone decanoate) or matching (2 ml arachis oil vehicle) placebo for 4 weeks.

MAIN OUTCOME MEASURES

Comprehensive measures of cardiac muscle function involving transthoracic cardiac echocardiography measuring myocardial tissue velocity, peak systolic strain and strain rates, and bioimpedance measurement of cardiac output and systematic vascular resistance.

RESULTS

Left ventricular (LV) function (LV ejection fraction, LV modified TEI index), right ventricular (RV) function (ejection area, tricuspid annular systolic planar motion, RV modified TEI index) as well as cardiac afterload (mean arterial pressure, systemic vascular resistance) and overall cardiac contractility (stroke volume, cardiac output) were within age- and gender-specific reference ranges and were not significantly (P < 0.05) altered by either androgen or placebo over 4 weeks of treatment. Minor changes remaining within normal range were observed solely within the testosterone group for: increased LV end-systolic diameter (30 +/- 7 vs. 33 +/- 5 mm, P = 0.04) and RV end-systolic area (12.8 +/- 1.3 vs. 14.6 +/- 3.3 cm(2), P = 0.04), reduced LV diastolic septal velocity (Em, 9.5 +/- 2.6 vs. 8.7 +/- 2.0 cm/s, P = 0.006), increased LV filling pressure (E/Em ratio, 7.1 +/- 1.6 vs. 8.3 +/- 1.8, P = 0.02) and shortened PR interval on the electrocardiogram (167 +/- 13 vs. 154 +/- 12, P = 0.03).

CONCLUSION

Four weeks of treatment with testosterone or nandrolone had no beneficial or adverse effects compared with placebo on cardiac function in healthy young men.

Blood testosterone threshold for androgen deficiency symptoms

There are few systematic studies of the relationship between blood testosterone concentrations and the symptoms of overt androgen deficiency. Because most testosterone preparations are relatively short-term, the rapid changes in blood testosterone concentrations they cause make it difficult to define any testosterone threshold. By contrast, subdermal testosterone implants provide stable blood testosterone concentrations over days to weeks, while gradually declining to baseline over 5-7 months. Hence, this provides an opportunity to define a blood testosterone threshold for androgen deficiency symptoms by observing androgen-deficient men as their familiar androgen deficiency symptoms return as testosterone pellets slowly dissolve. Among 52 androgen-deficient men who underwent 260 implantations over 5 yr, at the time of return of androgen deficiency symptoms the blood total and free testosterone concentrations were highly reproducible within individuals (F = 0.8, P = 0.49 and F = 1.4, 0.24, respectively) but varied markedly between men (F = 167 and F = 138, both P < 0.001), indicating that each person had a consistent testosterone threshold for androgen deficiency symptoms that differed markedly between individuals. The most reported symptoms of androgen deficiency were lack of energy, lack of motivation, and reduced libido. The symptomatic threshold was significantly lower in men with secondary hypogonadism compared with men with primary or mixed hypogonadism (total, 9.7 +/- 0.5 nmol/liter vs. 11.7 +/- 0.4 nmol/liter and 10.2 +/- 0.3 nmol/liter, P = 0.006; free, 146 +/- 10 pmol/liter vs. 165 +/- 6 pmol/liter and 211 +/- 18 pmol/liter, P = 0.002) but was not affected by the underlying cause of hypogonadism or by specific symptoms of any severity. Despite a wide range in individual thresholds for androgen deficiency symptoms, the mean blood testosterone threshold corresponded to the lower end of the eugonadal reference range for young men. The implications of these observations for the development of more specific quality-of-life measures, as well as for other potential androgen deficiency states such as chronic diseases and aging, remain to be determined.

Testosterone release rate and duration of action of testosterone pellet implants

OBJECTIVE

Testosterone pellets are a highly effective subdermal depot administered at regular intervals with the timing individualized depending upon return of the patient's characteristic androgen deficiency symptoms. Yet the in vivo testosterone release rate and effective duration of action of these pellets has been little studied systematically.

DESIGN

Analysis of prospectively collected data from three randomized controlled clinical trials. Collection of extruded pellets.

PATIENTS

Androgen-deficient men (n = 136) undergoing long-term androgen replacement therapy with a standard dose (800 mg) of testosterone pellets implanted subdermally at intervals from 5 to 7 months.

MEASUREMENTS

Testosterone release rate of pellets, consisting of pure crystalline testosterone without excipients, is estimated by measuring the dry weight lost by pellets (n = 179) over their time in situ. The effective duration of the standard regimen, and the influence of extrusion and patient or procedural characteristics on it, was estimated by timing of return for re-implantation due to recurrence of the patient's familiar androgen deficiency symptoms.

RESULTS

The loss of dry weight of intact (n = 112) pellets was strongly correlated with time in situ (r2 = 0.969) providing an estimate of daily testosterone release rate per 200 mg pellet of 1.34 +/- 0.02 mg/pellet/day (95% CI 1.30-1.37 mg/day) for the first 3 months. After 756 implantations of the standard dose, men return for re-implantation at 5.8 calendar months following no or only a single pellet extrusion, but the time to return was significantly shorter after multiple extrusions. No patient or procedural features influenced the timing of return. Among men with primary hypogonadism, increases in plasma LH and FSH were more sensitive than plasma total or free testosterone to changes in testosterone delivery following an extrusion.

CONCLUSION

Testosterone pellet implants release testosterone at a steady rate of 1.3 mg/200 mg implant/day (95% CI). The duration of action is about 6 months in an uncomplicated cycle with timing of return shortened by extrusions only in the 3.6% of procedures followed by multiple extrusions. No other patient or procedural features influenced duration of action. Among men with an intact hypothalamo-pituitary unit, plasma gonadotropins are more sensitive than blood total or free testosterone to reduced testosterone delivery following an extrusion.

A randomised controlled clinical trial of antibiotic impregnation of testosterone pellet implants to reduce extrusion rate

OBJECTIVE

Testosterone pellet implantation is a safe, effective and convenient form of depot androgen replacement, with extrusion of pellets following about 10% of procedures the most frequent adverse effect. This study aimed to determine whether extrusion rate could be reduced by antibiotic impregnation of pellets immediately prior to implantation.

DESIGN

Prospective, randomised, parallel-group, open-label study design in a single centre. One hundred and eighty-six androgen-deficient men (400 implantation procedures) were randomised into either a group who had their pellets soaked for approximately 2 min in gentamicin solution prior to implantation, or a control group who had the standard implantation procedure.

METHODS

Extrusion, infection and/or bruising were evaluated prospectively by self-report from the participants, and retrospectively at subsequent implantation. Other variables (site, shaving, skin preparation, operator, pellet batch, bruising) were collected at implantation time.

RESULTS

The extrusion rate was 20% lower (odds ratio=0.80, 95% confidence interval (CI) 0.40-1.62) but not statistically different between the two groups (extrusion rate 23/205 (11.2%) for the control group vs 18/195 (9.2%) for the antibiotic-soak group, P=0.42). One operator experienced more total (P=0.0002) and infection-related (P=0.0008) extrusions and marginally more bruising (P=0.06) than other operators. The operator effect did not appear to be explained by differences in experience or implantation style. There was a 4.6-fold excess (95% CI 1.6-18.6) of multiple (19 vs 4 expected) over single (22 vs 10 expected) and no (359 vs 386 expected) extrusions. Extrusion was not related to batch number (P=0.15), location (P=0.15), shaving (P=0.32), old or new site (P=0.59), or the presence of suppuration or not (P=0.42); however, povidone-iodine skin disinfectant had statistically fewer extrusions than mixed alcohol solution.

CONCLUSIONS

Antibiotic impregnation prior to implantation does not significantly decrease testosterone pellet extrusion rate. An operator effect, not due to experience or procedural style, an excess of multiple extrusions and disinfectant effects were confirmed. Neither location, nor preparation of the site, nor pellet batch, influences extrusion rate.

Long-term outcomes of elective human sperm cryostorage

BACKGROUND

Sperm cryopreservation allows men with threatened fertility to preserve their progenitive potential, but there is little data on long-term outcomes of elective sperm cryostorage programmes.

METHODS AND RESULTS

Over 22 years, 930 men sought semen cryostorage in a single academic hospital, of which 833 (90%) had spermatozoa cryostored. Among 692 (74%) men surviving their illness, sperm samples were discarded for 193 (21% of all applicants, 28% of survivors) and cryostored spermatozoa were used for 64 men (7% of all applicants, 9% of survivors) in 85 treatment cycles commencing at a median of 36 months post-storage (range 12-180 months) with nearly 90% of usage started within 10 years of storage and none after 15 years. Pregnancy was most efficiently produced by intracytoplasmic sperm injection (median three cycles) compared with conventional IVF (median eight cycles) or artificial insemination (median more than six cycles; P < 0.05). A total of 141 (15%) of men had died and of these, 120 (85% of those dying) had their spermatozoa discarded; requests to prolong cryostorage were received from relatives of 21 men (2% of all applicants, 15% of deceased) of which three cases had spermatozoa transferred for use with no pregnancies reported. Sperm concentration was lower for all cryostorage groups compared with healthy sperm donor controls (P < 0.05). Following orchidectomy, men with testicular cancer had sperm density approximately half that of all other groups of men seeking cryostorage (P < 0.05), the lowering attributable to removal of one testis rather than in defects in spermatogenesis.

CONCLUSION

Elective sperm cryopreservation is an effective, if sparsely used, form of fertility insurance for men whose fertility is threatened by medical treatment and is an essential part of any comprehensive cancer care programme.

Influence of implantation site and track geometry on the extrusion rate and pharmacology of testosterone implants

BACKGROUND

Implantation of testosterone pellets under the lateral abdominal wall skin is an old but popular and effective form of androgen replacement therapy. Extrusion of one or more pellets remains the most frequent adverse event.

OBJECTIVE

To determine whether an alternative implantation site (hip) and/or track geometry (two vs. four tracks) would reduce extrusion rates compared with the standard of a four-track abdominal site. Additionally, the study aimed to evaluate the effects of site and track geometry on other adverse effects (bruising, infection) and the pharmacology of testosterone release from the implants.

DESIGN

A prospective, parallel-group unmasked study design in a single centre. The primary objective was to evaluate sites, with evaluation of track geometry a subordinate objective made necessary by anatomical differences. Accordingly, androgen deficient men requiring testosterone implantation with the standard dose (four 200 mg pellets) were randomized into one of three groups (ratio 1 : 1 : 2): a four-track abdomen site (standard), a two-track abdomen site or a two-track hip site. The pharmacological substudy was to evaluate the impact of site and track geometry on testosterone implant pharmacology by monthly hormone assays following implantation.

PATIENTS

Two hundred and forty-six implantation procedures involving 96 androgen deficient men.

MEASUREMENTS

The primary end-point, extrusion rate per procedure, and secondary end-points (bruising or infection post procedure) were evaluated prospectively by self-report from the participants, and verified when they returned next for implantation. The pharmacology substudy involved monthly blood sampling for hormone (total and free testosterone, LH, FSH) measurements.

RESULTS

The extrusion rate was significantly higher [odds ratio (OR) = 2.6, 95% confidence interval (CI) 1.1-7.1] for the hip site (15/125, 12%) compared with the abdominal site (6/121, 5%). Track geometry made no significant difference (OR = 1.05, 95% CI 0.2-5.4) to the extrusion rate. No secondary end-points (bruising, infection) were significantly different according to either site or track geometry. One operator who performed the implant procedures had significantly less primary and secondary adverse events than the other operators (P = 0.006). Neither implantation site, nor track geometry influenced pharmacokinetics [peak plasma total and free testosterone concentrations and net hormone release (area-under-curve, AUC)] or pharmacodynamics [nadir plasma LH and FSH and net suppression (AUC) in men with hypergonadotrophic hypogonadism].

CONCLUSIONS

We conclude that the hip site has a higher extrusion rate than the standard abdominal wall site but that track geometry does not increase the risk of extrusion. Neither implantation site, nor track geometry influenced either other adverse effects or the pharmacokinetics or pharmacodynamics of testosterone pellet implants.

A double-blind, placebo-controlled, randomized clinical trial of transdermal dihydrotestosterone gel on muscular strength, mobility, and quality of life in older men with partial androgen deficiency

The efficacy and safety of androgen supplementation in older men remains controversial. Despite biochemical evidence of partial androgen deficiency in older men, controlled studies using T demonstrate equivocal benefits. Furthermore, the importance of aromatization and 5alpha reduction in androgen actions among older men remains unclear. Dihydrotestosterone is the highest potency natural androgen with the additional features that it is neither aromatizable nor susceptible to potency amplification by 5alpha reduction. Therefore, the effects of dihydrotestosterone may differ from those of T in older men. This study evaluated the efficacy and safety of 3 months treatment with transdermal dihydrotestosterone gel on muscle strength, mobility, and quality of life in ambulant, community-dwelling men aged 60 yr or older. Eligible men (plasma T < or =15 nmol/liter) were randomized to undergo daily dermal application of 70 mg dihydrotestosterone gel (n = 18) or vehicle (n = 19) and were studied before, monthly during, and 1 month after treatment. Among 33 (17 dihydrotestosterone, 16 placebo) men completing the study with a high degree of compliance, dihydrotestosterone had significant effects on circulating hormones (increased dihydrotestosterone; decreased total and free testosterone, LH, and FSH; unchanged SHBG and estradiol), lipid profiles (decreased total and low-density lipoprotein cholesterols; unchanged high-density lipoprotein cholesterol and triglycerides), hematopoiesis (increased hemoglobin, hematocrit, and red cell counts), and body composition (decreased skinfold thickness and fat mass; unchanged lean mass and waist to hip ratio). Muscle strength measured by isokinetic peak torque was increased in flexion of the dominant knee but not in knee extension or shoulder contraction, nor was there any significant change in gait, balance, or mobility tests, in cognitive function, or in quality of life scales. Dihydrotestosterone treatment had no adverse effects on prostate (unchanged prostate volumes and prostate-specific antigen) and cardiovascular (no adverse change in vascular reactivity or lipids) safety markers. We conclude that 3 months treatment with transdermal dihydrotestosterone gel demonstrates expected androgenic effects, short-term safety, and limited improvement in lower limb muscle strength but no change in physical functioning or cognitive function.

Effects of androgen deficiency and replacement on prostate zonal volumes

BACKGROUND AND OBJECTIVES

Androgens play a key role in prostate development and disease. However the effects of androgen deficiency and replacement on the prostate during mid-life are not well understood, and there is no information on their effects on prostate zonal volumes. This study aimed to define the effects of androgen deficiency and androgen replacement therapy on prostate zonal volumes (central, peripheral & total) using planimetric prostate ultrasound with particular emphasis on the central zone of the prostate, the most hormonally sensitive and fastest growing region of the prostate and the zone where nodular benign prostate hyperplasia originates.

PATIENTS AND MEASUREMENTS

Central and total prostate volume were measured directly, and peripheral prostate volume calculated, by a single observer using transrectal ultrasound in 71 hypogonadal men (aged 40 +/- 2, range 18-78 years) who were compared with individually age-matched health controls without prostate or gonadal disease. Among the men with androgen deficiency, 17 men had untreated androgen deficiency (never treated or no treatment for at least 6 months) and 54 men were receiving long-term androgen replacement therapy (median 32 months, 93% > or = 6 months) with testosterone implants (n = 27), testosterone ester injections (n = 24) or other testosterone treatment (n = 3).

RESULTS

Compared with individually age-matched controls, untreated androgen deficient men (n = 17) had reduced central (4.0 +/- 0.5 vs. 6.2 +/- 0.5 ml, P < 0.001) and total (23.4 +/- 2.6 vs. 29.2 +/- 1.6 ml, P < 0.001) prostate volumes whereas the reduction in peripheral prostate volume (19.4 +/- 2.1 vs. 23.0 +/- 1.3 ml, P = 0.15) was not statistically significant. Men with treated androgen deficiency (n = 54) also still had significantly reduced central (4.8 +/- 0.4 vs. 6.8 +/- 0.4, P < 0.001), peripheral prostate volume (19.6 +/- 0.8 vs. 21.6 +/- 0.7 ml, P = 0.06) and total (24.4 +/- 1.1 vs. 28.4 +/- 1.0 ml, P = 0.008) despite prolonged restoration of physiological testosterone concentrations. Neither modality of testosterone treatment nor type of hypogonadism influenced prostate zonal volumes before or after treatment. In contrast, central, peripheral and total prostate volume increased with age among healthy controls and men with androgen deficiency regardless of androgen replacement therapy. Plasma PSA concentrations were reduced in men with untreated androgen deficiency and were similar to age-matched controls in men with treated androgen deficiency.

CONCLUSIONS

We conclude that, during mid-life, chronic androgen deficiency due to hypogonadism is associated with reduced central, peripheral and total prostate volumes. Reduced prostate volumes persist even during long-term maintenance of effective androgen replacement therapy with physiological testosterone concentrations until the fourth decade of life. After that, prostate volumes increase with age regardless of androgen deficiency or replacement. These findings suggest that, during mid-life, age is a more important determinant of prostate growth than ambient testosterone concentrations maintained in the physiological range. The persistently subnormal prostate volumes despite adequate androgen replacement therapy may explain the apparent paucity of cases of overt prostate disease among testosterone-treated androgen deficient men who retain protection against prostate disease despite physiological androgen replacement therapy.

Use, misuse and abuse of androgens. The Endocrine Society of Australia consensus guidelines for androgen prescribing

Androgen replacement therapy (ART) is usually life-long, and should only be started after androgen deficiency has been proven by hormone assays. The therapeutic goal is to maintain physiological testosterone levels. Testosterone rather than synthetic androgens should be used. Oral 17 alpha-alkylated androgens are hepatotoxic and should not be used for ART. There is no indication for androgen therapy in male infertility. Although androgen deficiency is an uncommon cause of erectile dysfunction, all men presenting with erectile dysfunction should be evaluated for androgen deficiency. If androgen deficiency is confirmed, investigation for the underlying pathological cause is required. Contraindications to androgen therapy are prostate and breast cancer. Precautions include using lower starting doses for older men and induction of puberty. Intramuscular injections should be avoided in men with bleeding disorders. Androgen-sensitive epilepsy, migraine, sleep apnoea, polycythaemia or fluid overload need to be considered. Competitive athletes should be warned about the risks of disqualification. ART should be initiated with intramuscular injections of testosterone esters, 250 mg every two weeks [corrected]. Maintenance requires tailoring treatment modality to the patient's convenience. Modalities currently available include testosterone injections, implants, or capsules. Choice depends on convenience, cost, availability and familiarity. There is no convincing evidence that, in the absence of proven androgen deficiency, androgen therapy is effective and safe for older men per se, in men with chronic non-gonadal disease, or for treatment of non-specific symptoms. Until further evidence is available, such treatment cannot be recommended.

Oestradiol enhances testosterone-induced suppression of human spermatogenesis

The aim of this study was to determine for the first time in humans, the efficacy of adding a low dose oestradiol to a suboptimally suppressive testosterone dose in a depot hormonal regimen to suppress spermatogenesis in healthy eugonadal men. Twenty-six healthy men were randomized into groups that were treated by a single subdermal implantation of either 600 mg testosterone alone (T; n = 11) or together with 10 mg (TE10, n = 7) or 20 mg (TE20, n = 8) oestradiol. Administration of oestradiol produced a dose-dependent increase in peak plasma oestradiol at 1 month and prolonged suppression of plasma LH and FSH leading to significantly enhanced suppression of sperm output. Despite the augmented spermatogenic suppression, there was no significant difference in the proportions achieving azoospermia (6/26, 23%) or severe oligozoospermia (<1 or <3 x 10(6) spermatozoa per ml, 7/26, 27%) and overall these proportions were inadequate to provide reliable contraception according to the standards identified in World Health Organization male contraceptive efficacy studies. Total and free testosterone remained within the eugonadal reference range for young men throughout the study. While the lower oestradiol dosage had minimal spermatogenic suppression effects, the higher dose produced dose-limiting adverse effects of androgen deficiency and/or oestrogen excess between the fourth and sixth month of the study. This appeared to be due to the unexpectedly prolonged, low concentration of oestradiol release from the oestradiol implants. There were no significant treatment-related changes in body composition, lipids, prostate-specific antigen, haematological or biochemical variables. Thus oestradiol has a low therapeutic window and dose-limiting side-effects at dosages that fail to achieve the uniform azoospermia required of an effective male hormonal contraceptive regimen.

Extrusion of testosterone pellets: a randomized controlled clinical study

BACKGROUND

It has previously been shown that testosterone implantation is an effective and well accepted form of androgen replacement therapy, but that pellet extrusion was the most frequent side-effect. The present study aimed to reduce the extrusion rate.

OBJECTIVE

To determine whether the washing of testosterone pellets to remove potentially surface-adherent particles decreased the rate of extrusion of pellet implants.

DESIGN

Prospective, randomized parallel group design in a single centre with consecutive procedures to be randomized (1 : 1) into a wash or control group.

PATIENTS

The study included 251 testosterone implantation procedures in men with known androgen deficiency.

MEASUREMENTS

The primary endpoint, extrusion rate per procedure, was evaluated prospectively by telephone contact at 1 week and then 3 and 6 month intervals. Secondary end-points included peri-procedure adverse events (bleeding, skin reaction, excessive discomfort) noted at the time of implant. Bruising, bleeding and infection were also evaluated as later adverse events by telephone and personal follow-up. Explanatory variables recorded as possible covariables included the number of implants used, production batch number of the implants, the operator, as well as other demographic and medical factors.

RESULTS

In the wash group, the extrusion rate was 12% per procedure (19 pellets from 15 subjects) whereas in the control group, the extrusion rate was 11.1% per procedure (18 pellets from 14 subjects), indicating no evidence of any benefit of the wash procedure (OR = 1. 09 [95% CI 0.47-2.6] per procedure). There was no evidence of benefit in secondary endpoints including total adverse events (7.1%, OR 1.28 [0.44-3.9], bleeding/bruising (8.8%, 1.23 [0.47-3.3]) and infection (4.0%, 1.54 [0.35-7.6]) per procedure. Among men reporting an infection requiring antibiotic treatment according to their own general practitioners, six/ten (60%) subsequently experienced an extrusion. There were no significant differences in extrusion rate between four different operators (P = 0.24) nor among 12 different batches of pellets used during the course of the study (P = 0.77).

CONCLUSIONS

The pellet washing procedure used during implantation does not reduce the subsequent extrusion rate. The higher rate of both primary and secondary adverse events in this prospective study compared with the previous retrospective survey may reflect either more rigorous follow-up or a secular trend.

Efficacy and safety of recombinant human follicle stimulating hormone (Gonal-F) with urinary human chorionic gonadotrophin for induction of spermatogenesis and fertility in gonadotrophin-deficient men

In order to evaluate the efficacy and safety of recombinant human follicle stimulating hormone (r-hFSH) in combination with urinary human chorionic gonadotrophin (HCG) to induce spermatogenesis and fertility in gonadotrophin-deficient men, we conducted a prospective, open, non-comparative multicentre study in two Australian academic medical centres. Ten men with gonadotrophin deficiency requiring induction of spermatogenesis and fertility were treated with HCG for 3-6 months followed by the s.c. self-administration of injections of r-hFSH in combination with HCG for 18 months. Among the eight men who commenced r-hFSH treatment, seven demonstrated sperm output at a median of 6 months and five achieved the target sperm output of 1. 5x10(6) per ml at a median of 9 months of FSH treatment. Mean testicular volume increased by 4.2 ml during FSH treatment. Three men produced pregnancies in their partners, two of which resulted in the birth of healthy babies and a third patient's partner had a miscarriage. We conclude that r-hFSH is well tolerated and effective in inducing testis growth, spermatogenesis and fertility in gonadotrophin-deficient men. The efficacy of r-hFSH seems comparable with urinary FSH at restoring normal fertility in gonadotrophin-deficient men.

An analysis of testosterone implants for androgen replacement therapy

OBJECTIVE

To review 13 years of experience using fused crystalline testosterone implants for androgen replacement therapy in order to identify pattern of usage (including continuation rates) and adverse events emerging during therapy and factors associated with adverse events including implant extrusions.

DESIGN

Retrospective review of prospectively collected data on characteristics of patients and implant procedures performed as well as adverse events reported during routine follow-up.

PATIENTS

Over 13 years 973 implant procedures using fused crystalline testosterone implants were performed in 221 men.

MEASUREMENTS

Continuation rates and adverse events such as extrusions, bleeding, infection or others were recorded and analysed in relationship to characteristics of the patient and the implant procedure performed.

RESULTS

Overall rate of adverse events (108/73, 11.1%) was significantly related to increased numbers of implants (4.2 +/- 0.1 vs 4.0 +/- 0.03, P = 0.031) and higher levels of physical activity at work (P = 0.030). The most common adverse effect was extrusion (83/973, 8.5%) which was related to occupational classification (P = 0.033) and increasing work activity (P = 0.044) and occurred more frequently than by chance in multiple (16 vs 3.3 expected) rather than single (65 vs 76.1 expected) episodes. Bleeding (22/973, 2.3%) was significantly associated with an increased number of implants (4.5 +/- 0.2 vs 4.0 +/- 0.03, P = 0.020) but even in the worst cases (3/22) it was of minor clinical importance. Infection was rare (6/973, 0.6%) but occurred more among thinner men. The overall continuation rate was 92.7% increasing from 86% after the first implantation to > 99% after the tenth implant.

CONCLUSIONS

This study demonstrates the very satisfactory clinical acceptability of testosterone pellet implants for androgen replacement therapy within a single unit with experienced operators. The only regular adverse effect is extrusion, which may be related to mechanical factors such as habitual work activity but also possibly procedural factors. Other adverse effects such as bleeding, infection and fibrosis were rare. An improved method of implant delivery would enhance this old but durable technology.

Pharmacokinetics and pharmacodynamics of nandrolone esters in oil vehicle: effects of ester, injection site and injection volume

We studied healthy men who underwent blood sampling for plasma nandrolone, testosterone and inhibin measurements before and for 32 days after a single i.m. injection of 100 mg of nandrolone ester in arachis oil. Twenty-three men were randomized into groups receiving nandrolone phenylpropionate (group 1, n = 7) or nandrolone decanoate (group 2, n = 6) injected into the gluteal muscle in 4 ml of arachis oil vehicle or nandrolone decanoate in 1 ml of arachis oil vehicle injected into either the gluteal (group 3, n = 5) or deltoid (group 4, n = 5) muscles. Plasma nandrolone, testosterone and inhibin concentrations were analyzed by a mixed-effects indirect response model. Plasma nandrolone concentrations were influenced (P < .001) by different esters and injection sites, with higher and earlier peaks with the phenylpropionate ester, compared with the decanoate ester. After nandrolone decanoate injection, the highest bioavailability and peak nandrolone levels were observed with the 1-ml gluteal injection. Plasma testosterone concentrations were also influenced (P < .001) by the ester and injection site, with the most rapid, but briefest, suppression being due to the phenylpropionate ester, whereas the most sustained suppression was achieved with the 1-ml gluteal injection. Plasma inhibin concentrations were also significantly influenced by injection volume and site, with the lowest nadir occurring after the nandrolone decanoate 1-ml gluteal injection. Thus, the bioavailability and physiological effects of a nandrolone ester in an oil vehicle are greatest when the ester is injected in a small (1 ml vs. 4 ml) volume and into the gluteal vs. deltoid muscle. We conclude that the side-chain ester and the injection site and volume influence the pharmacokinetics and pharmacodynamics of nandrolone esters in an oil vehicle in men.

Establishing the minimum effective dose and additive effects of depot progestin in suppression of human spermatogenesis by a testosterone depot

Hormonally induced azoospermia induced by weekly im injections of testosterone enanthate provides effective and reversible male contraception, but more practical regimens are needed. Given our previous findings that six 200-mg pellets implanted subdermally produced more stable, physiological T levels and reduced the delivered T dose by more than 50% while maintaining equally effective suppression of sperm output with fewer metabolic side-effects than weekly 200-mg testosterone enanthate injections, we sought in this study to determine 1) whether further dose-sparing could be achieved by lower testosterone doses while maintaining efficacy and 2) the efficacy of adding a depot progestin to a suboptimally suppressive depot testosterone dose as a model depot progestin/androgen combination male contraceptive. Healthy volunteers were randomized into groups (n = 10) who received either of two lower T doses (two or four 200-mg T pellets) or four 200-mg T pellets plus a single im injection of 300 mg depot medroxyprogesterone acetate (DMPA). Two T pellets (400 mg, 3 mg/day) had a negligible effect on sperm output. Four T pellets (800 mg, 6 mg/day) suppressed sperm output between the second to fourth postimplant months; output returned to normal by the seventh postimplant month, although only 4 of 10 men became azoospermic or severely oligozoospermic (< 3 mol/L/mL). The addition of a depot progestin markedly increased the extent, but not the rate, of sperm output suppression, with 9 of 10 becoming azoospermic and 10 of 10 becoming severely oligozoospermic. There were no serious adverse effects during the study. Plasma total and free testosterone levels remained within the eugonadal range at all times with each treatment. Plasma epitestosterone was suppressed by all 3 regimens, consistent with a dose-dependent inhibition of endogenous Leydig cell steroidogenesis. Plasma LH and FSH measured by a two-site immunoassay were suppressed in a dose-dependent fashion by T and further suppressed by the addition of DMPA. Sex hormone-binding globulin levels were decreased by DMPA, but not by either T dose. Prostate-specific antigen and lipids (total, low or high density lipoprotein cholesterol, and triglycerides) were not significantly changed in any group. Thus, a depot testosterone preparation with zero order release must be delivered at between 6-9 mg/day to provide optimal (but not uniform) efficacy at inducing azoospermia. The addition of a single depot dose of a progestin to a suboptimal testosterone dose (6 mg/day) markedly enhances the extent, but not the rate, of spermatogenic suppression, with negligible biochemical androgenic side-effects. These findings provide a basis for the use of a progestin/androgen combination depot for hormonal male contraception.

Hypothalamic-pituitary-testicular function in end-stage non-alcoholic liver disease before and after liver transplantation

OBJECTIVE

Gonadal dysfunction is common in chronic liver disease, but most of the previous studies have been restricted to men with alcohol-induced liver disease. We have evaluated hypothalamic-pituitary-testicular function in patients with end-stage non-alcoholic liver disease before and at 6 and 12 months after hepatic transplantation.

DESIGN

A prospective study of hypothalamic-pituitary-testicular endocrine function before and after cadaveric hepatic transplantation.

PATIENTS

Fifty four consecutive patients with end-stage, non-alcoholic liver disease were evaluated before and after liver transplantation.

MEASUREMENTS

Hypothalamic-pituitary-testicular (HPT) axis function was evaluated under basal conditions by single morning measurements of plasma total and free testosterone, sex hormone-binding globulin and by plasma LH and FSH responses to 100 micrograms i.v. GnRH.

RESULTS

Men with chronic non-alcoholic liver disease had reduced levels of total and free testosterone and increased levels of SHBG compared with controls with normal liver function. Total and free testosterone were positively correlated with basal and stimulated LH (but not FSH) concentrations. Gonadotrophin responses to GnRH were preserved but delayed compared with healthy controls consistent with a predominantly hypothalamic defect in regulation of pituitary-testicular function. Increasing severity of underlying liver disease was associated with declining total and free testosterone as well as peak GnRH-stimulated LH concentrations. Spironolactone treatment was associated with decreased circulating testosterone levels only in men with liver disease of intermediate severity (Child-Pugh class B). Following hepatic transplantation, total and free testosterone and SHBG concentrations returned progressively towards eugonadal control levels over the first 12 months but total and free testosterone levels remained subnormal.

CONCLUSIONS

Hypothalamic-pituitary regulation of testicular function is impaired in end-stage non-alcoholic liver disease in proportion to the severity of underlying liver disease. Spironolactone reduces circulating testosterone but only among men with Child-Pugh B liver cirrhosis. Gonadal function improves, but is not normalized, over the first year following successful liver transplantation.

Pharmacokinetics of human follicle-stimulating hormone in gonadotropin-deficient men

Gonadotropin treatment of hypogonadotropic infertile men usually requires regular im administration of human urinary FSH (uFSH); however, testicular function is rarely normalized despite years of treatment. As the pharmacokinetics of standard FSH doses (75 IU, two or three times weekly) in gonadotropin-deficient men are poorly characterized, we studied 10 gonadotropin-deficient men by measuring plasma FSH levels with an ultrasensitive fluoroimmunoassay (Delfia, Pharmacia) in single dose and multidose studies. The single dose studies involved blood samples taken 15 min before and 0, 1, 2, 4, 6, 8, 10, 12, 15, 18, 21, 24, 48, 72, and 96 h after the injection of 75 IU uFSH in 1 mL diluent, either sc under the abdominal wall skin or im into the deltoid muscle, in a random sequence, cross-over design (n = 7 men) and after the injection of 150 IU, sc, with additional blood sampling at 120 and 168 h (n = 7 men). The multidose studies used a fixed ascending dose sequence, with blood sampled at 24-h intervals posttreatment after at least 1 month of regular administration of either 75 or 150 IU uFSH, sc, at injection intervals of 72, 48, and 24 h (n = 6 men). From the single dose studies, pharmacokinetic variables were estimated from a one-compartment open model fitted by a weighted polyexponential curve fit of plasma FSH over time. The bioavailability of uFSH via the sc route was high (mean area under the curve, 90% for 75 IU and 143% for 150 IU vs. 75 IU, im). Peak plasma FSH levels were later (21.1 vs. 7.1 h; P < 0.001) and lower (2.0 vs. 2.7 IU/L; P < 0.001) after sc compared with im administration of 75 IU due to a slower absorption half-time (6.1 h vs. 1.4 h; P < 0.001), whereas mean residence times and clearance half-times were similar. The pharmacokinetic features of the 150- and 75-IU doses sc were essentially identical, apart from expected dose-dependent increases in peak plasma FSH level (2.8 vs. 2.0 IU/L; P < 0.001) and area under the curve (206 vs. 129 IU.h/L; P < 0.05). Multidose simulations based on the single dose pharmacokinetic models predicted that during chronic sc administration of standard FSH doses, plasma FSH levels would be in the lower half of the eugonadal range and fluctuate less than with im administration. The multidose study confirmed empirically these predictions. These studies form a pharmacological basis for a more flexible, cost-effective, and convenient self-administered sc regimen.(ABSTRACT TRUNCATED AT 400 WORDS)

Tolerability of intramuscular injections of testosterone ester in oil vehicle

We undertook a prospective survey of the tolerability of deep i.m. injections of testosterone enanthate in a castor oil vehicle, the most widely used form of androgen replacement therapy. Over a period of 8 months, 26 men received 551 weekly injections into the gluteal, deltoid or thigh muscle and side-effects were recorded immediately and 1 week after each injection by the same nurse using a standardized questionnaire. Most injections caused no complaints [389/551, 70.6% (95% confidence interval 66.6-74.4%)] but minor local side-effects, mostly pain and bleeding, were common [162/551, 29.4% (25.6-33.4%)]; no serious side-effects were observed. Considering all side-effects, the gluteal site had fewer complaints and was less prone to bleeding but was painful more often than deltoid or thigh injection sites. The laterality of injection at any site had no significant effect on side-effects. The only systemic side-effect was episodes of sudden-onset, non-productive cough associated with faintness following eight injections [1.5% (0.6-2.9%)] which we speculate may have been due to pulmonary oil microembolism. We conclude that, when administered by an experienced nurse, deep i.m. injection of testosterone enanthate in a castor oil vehicle is generally safe and well tolerated but causes relatively frequent minor side-effects, including pain and bleeding. An improved depot form of testosterone would be highly desirable for androgen replacement therapy and hormonal male contraception.

Activity of a nitrofurazone matrix urinary catheter against catheter-associated uropathogens

Nitrofurazone-coated urinary catheter segments inhibited 51 (75%) of 70 urinary bacterial isolates from patients with indwelling catheters. Inhibition zones correlated significantly with the nitrofurazone MIC (r2 = 0.79, P = 0.0001). All strains except the Pseudomonas spp. were inhibited by < or = 64 micrograms of nitrofurazone per ml. MICs of nitrofurazone and nitrofurantoin correlated significantly (r2 = 0.93, P = 0.0001).

Hypothalamic-pituitary adrenal function in end-stage non-alcoholic liver disease

Patients with end-stage liver disease have significant mortality often associated with intercurrent episodes of bleeding or sepsis. Intact adrenal function is essential in such situations. In order to test the hypothesis that adrenal insufficiency might be present in severe liver disease, hypothalamic-pituitary adrenal function was evaluated in patients with end-stage liver disease awaiting transplantation. The study had a prospective, open comparative design with patients restricted to those having non-alcoholic liver disease in order to avoid the confounding direct effects of alcohol on adrenocortical function. Fifty-one consecutive patients with end-stage, non-alcoholic liver disease undergoing evaluation for liver transplantation and 40 healthy controls were studied. Patients who had used corticosteroids (n = 8) or who were unable to complete the investigations (n = 5) were excluded leaving 38 patients eligible for analysis. Adrenal function was evaluated under basal conditions by single morning measurements of plasma total and free cortisol, corticosteroid-binding globulin, dehydroepiandrosterone sulfate and by adrenal stimulation indirectly using insulin-induced (0.1 U/kg, i.v.) hypoglycaemia and/or directly by adrenocorticotrophic hormone (ACTH); 250 micrograms tetracosactrin, i.v.) stimulation. Compared with healthy controls, patients with liver disease had a 64% reduction in maximal increments of plasma cortisol to indirect adrenal stimulation via insulin-induced hypoglycaemia and a 39% reduction to direct adrenal stimulation by ACTH (all P < 0.001). There was a significant negative correlation between the severity of underlying liver disease as assessed by Child-Pugh scores and peak control responses to ACTH (r = -0.647, P < 0.0001) and insulin-induced hypoglycaemia (r = -0.597, P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Suppression of human spermatogenesis by testosterone implants

Hormonally induced azoospermia is an effective, reversible form of male contraception; however, some men treated with weekly im testosterone enanthate (TE) injections fail to become azoospermic. As weekly injections cause widely fluctuating and supraphysiological testosterone levels, we tested the hypothesis that more stable, physiological testosterone levels would consistently produce azoospermia. Using a depot testosterone formulation which provides stable, physiological range testosterone levels for up to 6 months, we studied nine men before and after insertion of six 200 mg testosterone implants under the abdominal wall skin and compared the results with 38 men treated in a previous study with weekly im injections of 200 mg TE. Testosterone implants suppressed sperm output to near-azoospermia between the second to fourth postimplant months returning to normal by the sixth postimplant month. The fall in sperm output at the first month was greater after testosterone implants than TE injections (58% vs. 17%, P = 0.011) but similar proportions of men became azoospermic (5/9 vs. 25/38) or severely oligozoospermic (< 1 million/ml; 9/9 vs. 37/38). Plasma testosterone and estradiol levels remained mostly within the eugonadal range after implants but were markedly supraphysiological during TE injections. Both treatments suppressed immunoreactive LH and FSH to undetectable levels by ultrasensitive fluoroimmunoassay. Sex hormone-binding globulin levels were decreased and PRL levels increased by TE injections but neither was changed by testosterone implants. Prostate-specific antigen demonstrated a small rise of marginal significance (P = 0.065) after testosterone implants. Fewer men experienced acne after implants (0/9 vs. 25/38, p = 0.0004). Therefore a depot testosterone preparation with quasi-zero-order release demonstrates higher dose efficiency with similar (but not uniform) efficacy at inducing azoospermia but may cause fewer androgenic side-effects than weekly TE injections.

Pharmacokinetics and pharmacodynamics of testosterone pellets in man

We studied the pharmacokinetics and pharmacodynamics of sc implanted pellets of fused crystalline testosterone. Three different regimens (6 x 100 mg, 6 x 200 mg; and 3 x 200 mg) were compared in a prospective, cross-over clinical trial in which androgen deficient men were administered the three-dose combinations in a randomized starting order at intervals of at least 6 months. Plasma free and total testosterone, sex hormone-binding globulin, LH, and FSH were measured before and at monthly intervals for at least 6 months after 111 pellet implantation in 43 men with hypergonadotropic (n = 22) or hypogonadotropic (n = 21) hypogonadism. Total and free testosterone levels peaked at the first month and were maintained at physiological levels for 4 to 5 (600 mg doses) or 6 (1200 mg dose) months after a single implantation. Absorption of testosterone from 100 mg and 200 mg pellets closely approximated zero-order throughout the effective life of the pellets and exhibited a half-duration of 2.5 months. The estimated rate of release of testosterone was 1.5 (95% confidence limits 1.3-1.6) mg/day.200 mg pellet as determined from direct measurement of residue in pellets recovered after extrusion and confirmed independently from percent absorbed-time plots. The bioavailability of testosterone was virtually complete and the time course was predictable from the total implant dose and, to a lesser extent, total initial surface areas of pellets. Despite wide fluctuations in testosterone, SHBG levels were not changed during 6 months. In men with hypergonadotropic hypogonadism, both LH and FSH levels were uniformly and markedly suppressed by increased testosterone after pellet implants. LH and FSH were highly correlated with each other (r = 0.87) and inversely with total (r = 0.47 and 0.45, respectively) and free (r = 0.46 and 0.47) testosterone levels. Nadir LH levels occurred at 1-3 months (600 mg) and 1-4 months (1200 mg) reaching levels comparable with eugonadal controls. In contrast nadir FSH levels occurred at similar times but remained elevated compared with eugonadal controls. We conclude that fused pellets of crystalline testosterone provides very satisfactory depot androgen replacement exhibiting many desirable features for androgen replacement.

Randomized clinical trial of testosterone replacement therapy in hypogonadal men

We have compared the pharmacokinetics and pharmacodynamics of the three commonly used testosterone formulations in a prospective, randomized cross-over clinical trial. Plasma free and total testosterone and their ratio (proportion of unbound testosterone), sex hormone-binding globulin (SHBG), oestradiol, LH and FSH were measured in 15 hypogonadal men (nine hyper- and six hypogonadotrophic) who underwent, in a randomized sequence, three treatment periods each separated by an intervening washout period. The treatments were: (i) intramuscular injection of 250 mg mixed testosterone esters at 2-weekly intervals, (ii) oral testosterone undecanoate 120 mg bd, and (iii) subcutaneous testosterone pellets (6 x 100 mg). Pellet implantation gave the most prolonged effect with free and total testosterone levels being elevated for up to 4 months. This was accompanied by prompt and sustained suppression of plasma LH and FSH, an increase in plasma levels of oestradiol but no change in SHBG levels. In contrast, intramuscular injections induced marked but reproducible week-to-week fluctuations in free and total testosterone, which resulted in a small decrease in plasma SHBG levels, less marked suppression of LH and FSH and a smaller increase in plasma levels of oestradiol. Oral testosterone undecanoate produced the most variable plasma levels of free and total testosterone with a peak in the first treatment week and a fall thereafter and, despite maintenance of testosterone levels within the physiological range, there was no significant suppression of plasma levels of LH and FSH, and oestradiol levels were unchanged but levels of SHBG and total cholesterol were decreased. Free testosterone levels were increased disproportionately during testosterone treatment as the proportion of unbound testosterone was increased by all three treatments. All three testosterone preparations lowered plasma levels of urea and all were without biochemical or haematological toxicity. Reported sexual function was better maintained and side-effects were fewer with parenteral compared with oral treatments. The marked decrease in SHBG and cholesterol levels during oral testosterone undecanoate, when compared with parenteral treatments, occurred despite lesser androgenic effects (suppression of gonadotrophin levels and reported sexual function), which suggests that the liver is exposed to excessive androgenic load via the portal vein during oral treatment with testosterone esters. It is concluded that testosterone pellets give the closest approximation to zero-order (steady-state) delivery conditions for up to 4 months after a single insertion.(ABSTRACT TRUNCATED AT 400 WORDS)

Testicular function and fertility in men with homozygous alpha-1 antitrypsin deficiency

Fertility and testicular function were studied in eight men with severe homozygous (Pi ZZ variant genotype) alpha-1 antitrypsin (AAT) deficiency. Age- and marital duration standardized fertility, clinical androgenic features, mean testicular volume, plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and semen analysis were all normal apart from a reduction in semen volume. Mean plasma total and free testosterone were elevated and the percentage free testosterone reduced compared with age-matched, healthy fertile controls indicative of increased sex-hormone binding globulin (SHBG) levels representing an early marker for subclinical hepatic dysfunction associated with AAT-deficiency. In view of the preservation of normal fertility and testicular function despite chronic respiratory disease and premature death with deleterious AAT gene variants, it is proposed that the high prevalence of genetic polymorphism in the AAT protein may be maintained by the chronological asynchrony of the periods of maximal male reproductive activity (40 years) and the late onset (greater than 40 years) of symptoms in severe AAT deficiency rather than by any balance between reduced reproductive fitness of homozygotes and heterozygote advantage.

Testicular function and glycemic control in diabetic men. A controlled study

We have investigated testicular function in 28 insulin-dependent diabetic men under the age of 50 years and 119 age-matched controls. Diabetics had reduced testicular volume, semen volume, total and total motile sperm output while plasma LH and FSH levels were elevated. Reduction in semen volume and impotence were more common in long-standing complicated diabetes. Glycosylated hemoglobin (GHb) levels were positively correlated with plasma LH levels (r = 0.46, p less than 0.02) but there was no direct correlation of glycemic control and spermatogenesis. The differences in testicular function were due to decreased spermatogenesis and could not be explained by other forms of testicular pathology or the presence of diabetic neurovascular complications. We conclude that the function of the hypothalamic pituitary testicular axis is impaired in diabetic men, that this impairment is at least partly related to the degree of preceding glycemic control and that multiple levels of the axis may be dysfunctional.

Psychological and attitudinal profiles in donors for artificial insemination

Few objective data are available concerning the psychological profiles and attitudes of sperm donors in artificial insemination programs. We studied 30 consecutive new volunteers and 45 established sperm donors using the Cattell 16PF personality profile and an attitudinal survey concerning motives for donation, attitudes toward uses of sperm, desire for knowledge of outcomes, and attitudes toward disclosures of identifying and nonidentifying information between the parties to artificial insemination. Donors differed from the population norms in 7 of 16 first-order and 1 of 4 second-order personality factors, and this difference appeared to reflect their self-selection as donors. The predominant motive for donation was altruism, but secondary motives were also common. Financial motivation was very low in this population with few students. Donors approved of all current and most hypothetical uses of sperm but were not in favor of disclosures of information to other participants in the program. Restriction of disclosures to nonidentifying details was more acceptable. Unmarried donors were more often motivated for nonaltruistic reasons and were more in favor of disclosures. Attitudes of sperm donors were mostly stable over at least 3 years, but an increasing minority with time envisaged circumstances that might lead to their withdrawal from the program.

Testicular function in potential sperm donors: normal ranges and the effects of smoking and varicocele

Testicular exocrine (semen analysis) and endocrine (plasma LH, FSH, prolactin and testosterone) function was assessed in 119 consecutive healthy men presenting for screening as potential sperm donors. Since these volunteers were unbiased with respect to their fertility status, this sample of the general male population was suitable to determine normal ranges and the influence of a variety of physical (height, weight, standardized body weight, varicocele) and demographic (age, marital and fertility status, tobacco and alcohol consumption) factors on normal human testicular endocrine and exocrine function, without the confounding effects of bias in selection of subjects. The statistical distribution of all seminal parameters was non-gaussian, but cube-root transformation of the data normalized the distribution, allowing for parametric statistical analysis. The median (and 95% confidence limits) for the various semen parameters was 73.0 (10.6-235.3) million sperm per ml; 189.0 (12.6-868) million sperm per ejaculate; 50.4 (5.9-181.9) million motile sperm per ml; 133.0 (6.9-661.7) million motile sperm per ejaculate; 54.0 (7.0-172.9) million morphologically normal sperm per ml and 138.5 (7.5-672) million morphologically normal sperm per ejaculate. Testicular volume was correlated positively with measures of physique such as standardized body weight (r = 0.25, P less than 0.01) and body surface area (r = 0.30, P less than 0.002), and negatively with plasma levels of FSH (r = -0.31), P less than 0.002) but not LH. Sperm output was positively correlated with testicular volume (r = 0.28, P less than 0.005) and negatively correlated with plasma FSH (r = -0.31, P less than 0.002) and plasma LH (r = -0.31, P less than 0.002). Smoking was associated with a highly significant reduction in sperm output and motility. Men with varicocele (25%) were significantly taller, had slightly lower haemoglobin levels and moderate left (but not right) testicular atrophy, but neither seminal nor hormonal parameters were different from men without varicocele. There was no difference in any markers of human testicular function between men according to marital or fertility status, grades of moderate alcohol consumption or the presence of low titres of sperm antibodies.

Young's syndrome. Obstructive azoospermia and chronic sinopulmonary infections

We studied 29 men with Young's syndrome, a combination of obstructive azoospermia and chronic sinopulmonary infections. Men with this syndrome have only mildly impaired respiratory function and normal spermatogenesis; the azoospermia is due to obstruction of the epididymis by inspissated secretions. The diagnosis is based on the occurrence of chronic sinopulmonary infections, persistent azoospermia, normal spermatogenesis, and characteristic epididymal findings, as well as exclusion of cystic fibrosis and the immotile-cilia syndrome. The sperm themselves appear to be normal in Young's syndrome. Pregnancies had occurred in five couples; in three paternity was documented by genotyping. Thus, improved microsurgical and medical therapy might restore fertility. We suggest that Young's syndrome has a prevalence comparable to that of Klinefelter's syndrome and is a common cause of both chronic sinopulmonary infection and azoospermia.

Prevalence, testicular function and seminal parameters in men with sperm antibodies

A prospective survey of 289 unselected men, attending a male infertility clinic (200 subjects) or as donors presenting for an artificial insemination programme (89 subjects) was performed. High titres of sperm agglutinating antibodies (greater than 1/32) were present only in a group of (6.5%) of infertile men but not in volunteer donors. Low titres occurred with similar frequencies (12%) in both groups. The sperm immobilizing antibody test was less sensitive and more specific but of no additional diagnostic benefit. Patients with high titres of sperm antibodies had evidence of testicular damage with decreased testicular volumes, elevated serum FSH and LH levels and reduced sperm density and motility whereas low titres were not associated with any testicular or seminal pathology. These data suggest a sub-group of infertile men have evidence of spermatogenic damage and impaired sperm function associated with high titres of sperm antibodies. Immunologic infertility in these men may reflect either an underlying autoimmune orchitis or a secondary immune reaction following testicular damage of various causes.

Heterozygote detection in congenital adrenal hyperplasia

Detection of heterozygote carriers for congenital adrenal hyperplasia by use of a modified tetracosactide (a synthetic corticotropin) stimulation test with prior overnight dexamethasone suppression proved to have a diagnostic accuracy of 95%. Discrimination of heterozygotes from normals was best when we used a criterion based on the ratios of 17 alpha-hydroxyprogesterone to cortisol at baseline and at 30 min after intravenous administration of 250 micrograms of tetracosactide.

Heterozygote detection in congenital adrenal hyperplasia

Detection of heterozygote carriers for congenital adrenal hyperplasia by use of a modified tetracosactide (a synthetic corticotropin) stimulation test with prior overnight dexamethasone suppression proved to have a diagnostic accuracy of 95%. Discrimination of heterozygotes from normals was best when we used a criterion based on the ratios of 17 alpha-hydroxyprogesterone to cortisol at baseline and at 30 min after intravenous administration of 250 micrograms of tetracosactide.

Detection of varicocele by radionuclide blood-pool scanning

Varicocele is a common and treatable cause of male subfertility. The authors describe a new technique for varicocele detection using radionuclide blood-pool imaging of the scrotum. Of 83 patients studied, 29 had a clinically palpable varicocele of various sizes, and 26 of them were demonstrated by this technique. Two of the false negatives were bilateral varicoceles. In the 41 patients with no clinically detectable varicocele, there were 10 positive and 10 marginally asymmetric studies. The results indicate that this technique detects unilateral varicoceles with high sensitivity, including some which are subclinical. There may be significant implications for treatment of infertility.