Summary
Objectives The role of androgen decline in the sexual activity of adult males is controversial. To clarify whether sexual function would benefit from testosterone (T) treatment in men with ...partially or severely reduced serum T levels, we conducted a systematic review and meta‐analysis of placebo‐controlled studies published in the past 30 years. The aim of this study was to assess and compare the effects of T on the different domains of sexual life.
Data source A comprehensive search of all published randomized clinical trials was performed in MEDLINE, the Cochrane Library, EMBASE and Current Contents databases.
Review methods Guided by prespecified criteria, software‐assisted data ion and quality assessed by two independent reviewers, a total of 17 randomized placebo‐controlled trials were found to be eligible. For each domain of sexual function we calculated the standardized mean difference relative to T and reported the results of pooled estimates of T treatment using the random effect model of meta‐analysis. Heterogeneity, reproducibility and consistency of the findings across studies were explored using sensitivity and meta‐regression analysis.
Results Overall, 656 subjects were evaluated: 284 were randomized to T, 284 to placebo (P) and 88 treated in cross‐over. The median study length was 3 months (range 1–36 months). Our meta‐analysis showed that in men with an average T level at baseline below 12 nmol/l, T treatment moderately improved the number of nocturnal erections, sexual thoughts and motivation, number of successful intercourses, scores of erectile function and overall sexual satisfaction, whereas T had no effect on erectile function in eugonadal men compared to placebo. Heterogeneity was explored by grouping studies according to the characteristics of the study population. A cut‐off value of 10 nmol/l for the mean T of the study population failed to predict the effect of treatment, whereas the presence of risk factors for vasculogenic erectile dysfunction (ED), comorbidities and shorter evaluation periods were associated with greater treatment effects in the studies performed in hypogonadal, but not in eugonadal, men. Meta‐regression analysis showed that the effects of T on erectile function, but not libido, were inversely related to the mean baseline T concentration. The meta‐analysis of available studies indicates that T treatment might be useful for improving vasculogenic ED in selected subjects with low or low‐normal T levels. The evidence for a beneficial effect of T treatment on erectile function should be tempered with the caveats that the effect tends to decline over time, is progressively smaller with increasing baseline T levels, and long‐term safety data are not available. The present meta‐analysis highlights the need, and pitfalls, for large‐scale, long‐term, randomized controlled trials to formally investigate the efficacy of T replacement in symptomatic middle‐aged and elderly men with reduced T levels and ED.
We present a differential geometric approach to the problem of fault detection and isolation for nonlinear systems. A necessary condition for the problem to be solvable is derived in terms of an ...unobservability distribution, which is computable by means of suitable algorithms. The existence and regularity of such a distribution implies the existence of changes of coordinates in the state and in the output space which induce an "observable" quotient subsystem unaffected by all fault signals but one. For this subsystem, a fault detection filter is designed.
The morbidity and mortality of diabetes mellitus are mostly attributed to cardiovascular complications. Despite tremendous advancement in glycemic control, anti-diabetic medications have failed to ...revert vascular impairment once triggered by the metabolic disorder. The angiogenic growth factors, Angiopoietin-1 (Ang1) and Angiopoietin-2 (Ang2), are crucial regulators of vessel formation and maintenance starting with embryonic development and continuing through life. In mature vessels, angiopoietins control vascular permeability, inflammation and remodeling. A crucial role of angiopoietins is to drive vascular inflammation from the active to the quiescent state, enabling restoration of tissue homeostasis. The mechanism is of particular importance for healing and repair after damage, two conditions typically impaired in metabolic disorders. There is an emerging body of evidences suggesting that the imbalance of Ang1 and Ang2 regulation, leading to an increased Ang2/Ang1 ratio, represents a culprit of the vascular alterations of patients with type-2 diabetes mellitus. Pharmacological modulation of Ang1 or Ang2 actions may help prevent or delay the onset of diabetic vascular complications by restoring vessel function, favoring tissue repair and maintaining endothelial quiescence. In this review, we present a summary of the role of Ang1 and Ang2, their involvement in diabetic complications, and novel therapeutic strategies targeting angiopoietins to ameliorate vascular health in metabolic disorders.
Purpose
To provide the evidence-based recommendations on the role of testosterone (T) on age-related symptoms and signs remains.
Methods
The Italian Society of Andrology and Sexual Medicine (SIAMS) ...and the and the Italian Society of Endocrinology (SIE) commissioned an expert task force to provide an updated guideline on adult-onset male hypogonadism. Derived recommendations were based on Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.
Results
Clinical diagnosis of adult-onset hypogonadism should be based on a combination of clinical and biochemical parameters. Testosterone replacement therapy (TRT) should be offered to all symptomatic subjects with hypogonadism after the exclusion of possible contraindications. T gels and the long-acting injectable T are currently available preparations showing the best efficacy/safety profile. TRT can improve all aspects of sexual function, although its effect is limited in more complicated patients. Body composition (reducing fat mass and increasing lean mass) is improved after TRT, either in subjects with or without metabolic syndrome or type 2 diabetes. Conversely, the role of TRT in improving glycometabolic control is more conflicting. TRT can result in increasing bone mineral density, particularly at lumbar site, but no information on fracture risk is available. Limited data support the use of TRT for improving other outcomes, including mood frailty and mobility.
Conclusions
TRT can improve sexual function and body composition particularly in less complicated adult and in aging subjects with hypogonadism. When hypogonadism is adequately diagnosed, T appropriately prescribed and subjects correctly followed up, no short-term increased risk of adverse events is observed. Longer and larger studies are advisable to better clarify TRT long-term efficacy/safety profile.
Summary
In this paper, we study the problem of networks on nonlinear oscillators when communication topologies are disconnected. In the first part of this paper, we show that the high‐gain design ...procedure succeeds in achieving clustered consensus when disconnected topologies occur. In the second part, we study a network of nonlinear oscillators when the topology is switching between sets of disconnected and connected topologies. By a Lyapunov analysis, we prove that if disconnected topologies last for a limited amount of time and the switching law for connected topologies fulfills an average dwell‐time condition, synchronization is achieved.
Purpose
The recent pandemic of severe acute respiratory syndrome (SARS) due to coronavirus (CoV) 2 (SARS-CoV-2) has raised several concerns in reproductive medicine. The aim of this review is to ...summarize available evidence providing an official position statement of the Italian Society of Andrology and Sexual Medicine (SIAMS)
Methods
A comprehensive Pubmed, Web of Science, Embase, Medline and Cochrane library search was performed. Due to the limited evidence and the lack of studies, it was not possible to formulate recommendations according to the Oxford 2011 Levels of Evidence criteria.
Results
Several molecular characteristics of the SARS-CoV-2 can justify the presence of virus within the testis and possible alterations of spermatogenesis and endocrine function. Orchitis has been reported as a possible complication of SARS-CoV infection, but similar findings have not been reported for SARS-CoV-2. Alternatively, the orchitis could be the result of a vasculitis as COVID-19 has been associated with abnormalities in coagulation and the segmental vascularization of the testis could account for an orchitis-like syndrome. Finally, available data do not support the presence of SARS-CoV-2 in plasma seminal fluid of infected subjects.
Conclusion
Data derived from other SARS-CoV infections suggest that in patients recovered from COVID-19, especially for those in reproductive age, andrological consultation and evaluation of gonadal function including semen analysis should be suggested. Studies in larger cohorts of currently infected subjects are warranted to confirm (or exclude) the presence of risks for male gametes that are destined either for cryopreservation in liquid nitrogen or for assisted reproduction techniques.
Purpose
The short- and long-term andrological effects of coronavirus disease 2019 (COVID-19) have not been clarified. Our aim is to evaluate the available evidence regarding possible andrological ...consequences of COVID-19 either on seminal or hormonal parameters. The safety of the COVID-19 vaccines in terms of sperm quality was also investigated.
Methods
All prospective and retrospective observational studies reporting information on severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) mRNA semen and male genitalia tract detection (
n
= 19), as well as those reporting data on semen analysis (
n
= 5) and hormonal parameters (
n
= 11) in infected/recovered patients without any arbitrary restriction were included.
Results
Out of 204 retrieved articles, 35 were considered, including 2092 patients and 1138 controls with a mean age of 44.1 ± 12.6 years, and mean follow-up 24.3 ± 18.9 days. SARS-CoV-2 mRNA can be localized in male genitalia tracts during the acute phase of the disease. COVID-19 can result in short-term impaired sperm and T production. Available data cannot clarify long-term andrological effects. Low T observed in the acute phase of the disease is associated with an increased risk of being admitted to the Intensive Care Unit or death. The two available studies showed that the use of mRNA COVID-19 vaccines does not affect sperm quality.
Conclusions
The results of our analysis clearly suggest that each patient recovering from COVID-19 should be monitored to rule out sperm and T abnormalities. The specific contribution of reduced T levels during the acute phase of the infection needs to be better clarified.