Transgender health and the impact of aging and menopause.

Gender affirming hormone therapy (GAHT) is used by many transgender people to reduce gender incongruence and improve psychological functioning. As GAHT shares many similarities with menopausal hormone therapy, clinicians supporting people through menopause are ideally placed to manage GAHT. This narrative review provides an overview of transgender health and discusses long-term effects of GAHT to consider when managing transgender individuals across the lifespan. Menopause is less relevant for transgender individuals who take GAHT (often given lifelong) to achieve sex steroid concentrations generally in the range of the affirmed gender. For people using feminizing hormone therapy, there is an elevated risk of venous thromboembolism, myocardial infarction, stroke and osteoporosis relative to cisgender individuals. For trans people using masculinizing hormone therapy, there is an increased risk of polycythemia, probable higher risk of myocardial infarction and pelvic pain which is poorly understood. Proactive mitigation of cardiovascular risk factors is important for all transgender people and optimization of bone health is important for those using feminizing hormones. With a lack of research to guide GAHT in older age, a shared decision-making approach is recommended for the provision of GAHT to achieve individual goals whilst minimizing potential adverse effects.

Late-onset hypogonadism: metabolic impact.

BACKGROUND: Obesity and dysglycemia (comprising insulin resistance, the metabolic syndrome and type 2 diabetes), that is diabesity, are associated with reduced circulating testosterone and, in some men, clinical features consistent with androgen deficiency. OBJECTIVE: To review the metabolic impact of late-onset hypogonadism. METHODS: Comprehensive literature search with emphasis on recent publications. RESULTS: Obesity is one of the strongest modifiable risk factors for late-onset hypogonadism, and coexisting diabetes leads to further hypothalamic-pituitary-testicular axis suppression. The hypothalamic-pituitary-testicular axis suppression is functional and hence potentially reversible, and occurs predominantly at the level of the hypothalamus. While definitive mechanistic data are lacking, the evidence suggests that hypothalamic-pituitary-testicular axis suppression is mediated by dysregulation of pro-inflammatory cytokines leading to hypothalamic inflammation. Dysregulation of central leptin and insulin signaling may also contribute. In contrast, recent data challenge the paradigm that estradiol excess is a major contributor to hypothalamic-pituitary-testicular axis suppression. Instead, relative estradiol signaling deficiency may contribute to metabolic dysregulation in men with diabesity. While weight loss and optimization of comorbidities can reverse functional hypothalamic-pituitary-testicular axis suppression, testosterone treatment leads to metabolically favorable changes in body composition and to improvements in insulin resistance. DISCUSSION: The relationship between diabesity and late-onset hypogonadism is bidirectional. Preliminary evidence suggests that, in carefully selected men, lifestyle measures and testosterone treatment may have additive effects. CONCLUSIONS: While recent research has provided new insights into mechanistic and clinical aspects of diabesity-associated late-onset hypogonadism, more evidence from well-designed large trials is needed to guide the optimal clinical approach to such men.

Correlation of visceral adipose tissue measured by Lunar Prodigy dual X-ray absorptiometry with MRI and CT in older men.

Quantification of abdominal visceral adipose tissue (VAT) is important to understand obesity-related comorbidities. We hypothesized that dual X-ray absorptiometry (DXA) measurements of VAT would correlate with traditional gold standards of magnetic resonance imaging (MRI) and computed tomography (CT) in older men. Deming regression and Bland-Altman plots were used to assess the agreement between VAT measured simultaneously by DXA and MRI (n=95) in a cohort of older males participating in a randomized trial of testosterone replacement for diabetes. We also correlated DXA with single-slice CT (n=102) in a cohort of older males undergoing testosterone deprivation for prostate cancer. Lunar Prodigy DXA scanners using enCORE software was used to measure VAT. DXA VAT volume strongly correlated with MRI VAT volume (r=0.90, P<0.0001) and CT VAT area (r=0.83, P<0.0001). As DXA assesses VAT volume in a smaller compartment than MRI, Bland-Altman analysis demonstrated DXA systematically underestimated VAT by an approximately 30% proportional bias. DXA VAT volume measured by Lunar Prodigy DXA scanners correlate well with gold standard MRI and CT quantification methods, and provides a low radiation, efficient, cost-effective option. Future clinical studies examining the effects of interventions on body composition and regional fat distribution may find DXA an appropriate volumetric method to quantify VAT.

Laboratory astrochemistry: catalytic conversion of acetylene to polycyclic aromatic hydrocarbons over SiC grains.

Catalytic conversion reactions of acetylene on a solid SiC grain surface lead to the formation of polycyclic aromatic hydrocarbons (PAHs) and are expected to mimic chemical processes in certain astrophysical environments. Gas-phase PAHs and intermediates were detected in situ using time-of-flight mass spectrometry, and their formation was confirmed using GC-MS in a separate experiment by flowing acetylene gas through a fixed-bed reactor. Activation of acetylene correlated closely with the dangling bonds on the SiC surface which interact with and break the C-C π bond. The addition of acetylene to the resulting radical site forms a surface ring structure which desorbs from the surface. The results of HRTEM and TG indicate that soot and graphene formation on the SiC surface depends strongly on reaction temperature. We propose that PAHs as seen through the 'UIR' emission bands can be formed through decomposition of a graphene-like material, formed on the surface of SiC grains in carbon-rich circumstellar envelopes.

Testosterone levels increase in association with recovery from acute fracture in men.

UNLABELLED: In this longitudinal case-control study, acute fracture was associated with low serum testosterone, which was transient in 43% of men. While assessment of gonadal status is part of the assessment of bone fragility, measurement of testosterone in the early period after fracture may overestimate the prevalence of androgen deficiency. INTRODUCTION: Measurement of circulating testosterone is recommended in the evaluation of bone fragility in men. Since acute illness can transiently decrease circulating testosterone, we quantified the association of acute fracture and serum testosterone levels. METHODS: A case-control study was conducted involving 240 men with a radiologically confirmed minimal trauma fracture presenting to a tertiary referral hospital and 89 age-matched men without a history of minimal trauma fracture serving as controls. Follow-up testosterone levels 6 months after baseline were available for 98 cases and 27 controls. Results were expressed as the median and interquartile (IQR) range. RESULTS: Compared to controls, cases had lower total testosterone [TT, 7.2 (3.5, 10.8) vs 13.6 (10.9, 17.1) nmol/L, p < 0.001]. The 143 cases treated as inpatients had lower testosterone levels than the 97 cases treated as outpatients [TT 4.7 (2.3, 8.1) vs 10.3 (7.5, 12.7) nmol/L, p < 0.001]. Group differences in calculated free testosterone (cFT) were comparable to the group differences in TT. At follow-up, in 98 cases, median TT increased from 6.5 nmol/L (3.2, 8.5) to 9.6 nmol/L (6.9, 12.0) p < 0.0001, and SHBG remained unchanged. Of cases with low testosterone, 43% with TT <10 nmol/L and/or cFT <230 pmol/L at presentation were reclassified as androgen sufficient at follow-up. TT was unchanged in the controls. CONCLUSIONS: Low testosterone levels in men presenting with an acute fracture may, at least in part, be due to an acute, fracture-associated, stress response. To avoid over diagnosis, evaluation for testosterone deficiency should be deferred until recovery from the acute event.

(18)O(2) label mechanism of sulfur generation and characterization in properties over mesoporous Sm-based sorbents for hot coal gas desulfurization.

Using a sol-gel method, SmMeOx/MCM-41 or SBA-15 (Me=Fe, Co and Zn) and corresponding unsupported sorbents were prepared. The desulfurization performance of these sorbents was evaluated over a fixed-bed reactor and the effects of reaction temperature, feed and sorbent composition on desulfurization performance were studied. Samarium-based sorbents used to remove H2S from hot coal gas were reported for the first time. The results of successive sulfidation/regeneration cycles revealed that SmFeO3/SBA-15 sorbent was suitable for desulfurization of hot coal gas in the chemical industry. The formation of elemental sulfur during both sulfidation and regeneration processes depended strongly on the catalytic action of Sm2O2S species, which was confirmed for the first time via high sensitive time of flight mass spectrometer (TOF-MS) using 6%vol(18)O2/Ar regeneration gas and can reduce markedly procedural complexity. The sorbents were characterized using N2-adsorption, high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), temperature-programmed reduction of H2 (H2-TPR), thermogravimetry (TG) and time-of-flight mass spectrometry (TOF-MS) techniques.

Electronic transitions of palladium dimer.

The laser induced fluorescence spectrum of palladium dimer (Pd2) in the visible region between 480 and 700 nm has been observed and analyzed. The gas-phase Pd2 molecule was produced by laser ablation of palladium metal rod. Eleven vibrational bands were observed and assigned to the [17.1](3)Πg-X(3)Σu(+) transition system. The bond length (ro) and vibrational frequency (ΔG1∕2) of the ground X(3)Σu(+) state were determined to be 2.47(4) Å and 211.4(5) cm(-1), respectively. A molecular orbital energy level diagram was used to understand the observed ground and excited electronic states. This is the first gas-phase experimental investigation of the electronic transitions of Pd2.

Obesity and age as dominant correlates of low testosterone in men irrespective of diabetes status.

Although men with type 2 diabetes (T2D) frequently have lowered testosterone levels, it is not well established whether this is ascribable to the diabetic state per se, or because of other factors, such as obesity. Our objective was to determine the prevalence and correlates of low testosterone in middle-aged men with diabetes. We conducted a cross-sectional study in 240 men including 80 men with type 1 diabetes (T1D), 80 men with T2D and 80 men without diabetes. Prevalence of a total testosterone ≤8 nmol/L was low, occurring in none of the men with T1D, 6.2% of men with T2D and 2.5% of men without diabetes. Men with T1D had higher testosterone levels compared with men without diabetes (p < 0.001), even after adjustment for body mass index (BMI) and age (p < 0.02). While men with T2D had lower testosterone compared with controls (p = 0.03), this was no longer significant when BMI and age were taken into account (p = 0.16). In the entire cohort, TT remained inversely associated with BMI independent of age, sex hormone-binding globulin and diabetic status (p = 0.01), whereas calculated free testosterone (cFT) was independently and inversely associated with age (p < 0.001), but not with BMI (p = 0.47). These results suggest that marked reductions in circulating testosterone are uncommon in middle-aged men with diabetes. Increasing BMI and age are dominant drivers of lowered total and cFT, respectively, independent of the presence or absence of diabetes.

Electronic transitions of ruthenium monoxide.

The electronic transition spectrum of ruthenium monoxide (RuO) molecule in the spectral region between 545 nm to 640 nm has been recorded and analyzed using laser ablation/reaction free-jet expansion and laser induced fluorescence spectroscopy. The RuO molecule was produced by reacting laser-ablated ruthenium atoms with N2O seeded in argon. Nine vibrational bands were recorded, and they are identified to belong to four electronic transition systems, namely, the [18.1]Ω = 4-X(5)Δ4, [16.0]Ω = 5-X(5)Δ4, [18.1]Ω = 3-X(5)Δ3, and [15.8]Ω = 4-X(5)Δ3 systems. RuO was determined to have a X(5)Δ4 ground state. A least-squares fit of the measured rotational lines yielded molecular constants for the ground and the low-lying electronic states. A molecular orbital energy level diagram has been used to help with the assignment of the observed electronic states.

Catalytic conversion of acetylene to polycyclic aromatic hydrocarbons over particles of pyroxene and alumina.

Polycyclic aromatic hydrocarbons (PAHs) are known to be present in many astrophysical objects and environments, but our understanding of their formation mechanism(s) is far from satisfactory. In this paper, we describe an investigation of the catalytic conversion reaction of acetylene gas to PAHs over pyroxene and alumina. Crystalline silicates such as pyroxenes (with general formula [Mg, Fe]SiO3) and alumina (Al2O3) are observed astrophysically through their infrared spectra and are likely to promote grain surface chemical reactions. In the experiments reported here, gas-phase PAHs were produced by the catalytic reaction of acetylene over crystalline silicates and alumina using a pulsed jet expansion technique and the gaseous products detected using time-of-flight mass spectrometry. In a separate experiment, the catalytic formation of PAHs from acetylene was further confirmed with acetylene gas at atmospheric pressure flowing continuously through a fixed-bed reactor. The gas effluent and carbonaceous compounds deposited on the catalysts were dissolved separately in dichloromethane and analysed using gas chromatography-mass spectrometry. Among the samples studied, alumina showed higher activity than the pyroxene-type grains for the acetylene reaction. It is proposed that formation of the PAHs relies on the Mg²âº ions in the pyroxenes and Al³âº ions in alumina, where these ions act as Lewis acid sites. X-ray diffraction, Fourier transform infrared and high-resolution transmission electron microscopy techniques were used to characterize the structure and physical properties of the pyroxene and alumina samples.

Cardiovascular risk and bone loss in men undergoing androgen deprivation therapy for non-metastatic prostate cancer: implementation of standardized management guidelines.

Our objective was to evaluate the effectiveness of implementing standardized guidelines to mitigate metabolic and bone side effects of androgen deprivation therapy (ADT) in men with non-metastatic prostate cancer. We conducted a 2-year prospective cohort study at a tertiary referral teaching hospital. Overall, 236 men (mean age 69.8 ± 7.1) commencing ADT for non-metastatic prostate cancer attended a baseline clinic visit between 2007 and 2011, and 153 men were eligible for follow-up after 2 years of continuous ADT. Of these, 113 men had data available for analysis at 2 years. At baseline, 87% of the men were overweight or obese, 61% had hypertension, 56% had hypercholesterolaemia, 27% prior cardiovascular disease, 11% osteoporosis and 40% osteopaenia. After 2 years of ADT, there was an increase in waist circumference (+2.8 ± 6.3 cm, p = 0.002), and, in men without diabetes, in HbA1c (+0.13 ± 0.34%, p = 0.019). Despite this, due to treatment, there were significant reductions in total cholesterol (-0.35 ± 1.00 mmol/L, p < 0.001), and blood pressure (systolic -7.6 ± 19.3 mmHg; diastolic -4.7 ± 11.6 mmHg, p < 0.001). After 2 years, men not receiving anti-resorptive therapy experienced a significant decline in lumbar spine (-0.042 ± 0.134 g/cm(2) , p = 0.012) and total hip bone mineral density (BMD) (-0.026 ± 0.036 g/cm(2) , p < 0.001), whereas bisphosphonate treatment maintained stable BMD. Prevalence of anaemia increased from 13.8 to 32.5%. Older age independently predicted a greater drop in haemoglobin (p = 0.005). We conclude that a structured approach to assess and treat men undergoing ADT effectively improves cardiovascular risk factors and prevents bone decay. Larger studies are needed to determine effects on cardiovascular outcomes, fracture prevention and survival.

Laser-induced dissociation of singly protonated peptides at 193 and 266 nm within a hybrid linear ion trap mass spectrometer.

RATIONALE: We implemented, for the first time, laser-induced dissociation (LID) within a modified hybrid linear ion trap mass spectrometer, QTrap, while preserving the original scanning capabilities and routine performance of the instrument. METHODS: Precursor ions of interest were mass-selected in the first quadrupole (Q1), trapped in the radiofrequency-only quadrupole (q2), photodissociated under irradiation with a 193- or 266-nm laser beam in the third quadrupole (q3), and mass-analyzed using the linear ion trap. RESULTS: LID of singly charged protonated peptides revealed, in addition to conventional amide-bond cleavages, preferential fragmentation at Cα -C/N-Cα bonds of the backbone as well as at the Cα -Cß /Cß -Cγ bonds of the side-chains. The LID spectra of [M+H](+) featured product ions that were very similar to the observed radical-induced fragmentations in the CID spectra of analogous odd-electron radical cations generated through dissociative electron-transfer in metal-ligand-peptide complexes or through laser photolysis of iodopeptides. CONCLUSIONS: LID of [M+H](+) ions results in fragmentation channels that are comparable with those observed upon the CID of M(•+) ions, with a range of fascinating radical-induced fragmentations.

Laser absorption spectroscopy of the d3Π(g) ← c3Σ(u)+ transition of C2.

High-resolution laser absorption spectroscopy using concentration modulation has been applied to record the near-infrared spectrum of C2 in an AC hollow-cathode discharge of acetylene/helium mixtures. The (2,1) and (1,0) vibronic bands of the d3Π(g)­ c3Σ(u)+ system have been observed in the spectral region between 12,010 and 12,540 cm(­1). While the analysis of the (1,0) band was straightforward, the (2,1) band was found to be perturbed. Using the effective Hamiltonians for 3Π and 3Σ+ states, molecular constants for the vibrational levels of the c3Σ(u)+ state were retrieved in least-squares fits of the observed spectral lines. The experimental conditions, detailed analysis of the perturbations, and the determined molecular constants are reported.

Electronic transition of palladium monoboride.

The laser-induced fluorescence spectrum of palladium monoboride (PdB) in the visible region between 465 and 520 nm has been observed and analyzed. Gas-phase PdB molecules were produced by the reaction of diborane (B(2)H(6)) seeded in argon with laser ablated palladium atoms. Thirteen vibrational bands have been recorded, which included transitions of both Pd(10)B and Pd(11)B isotopic species. These bands belong to the [19.7](2)Σ(+)-X(2)Σ(+) system, with ground X(2)Σ(+) state bond length, r(o), determined to be 1.7278 Å. A molecular orbital energy level diagram was used to understand the observed ground and excited electronic states. This work represents the first experimental investigation of the electronic spectroscopy of the PdB molecule.

Electronic transitions of platinum monoboride.

The electronic transition spectrum of platinum monoboride (PtB) radical has been observed for the first time. Using laser vaporization∕reaction free jet expansion and laser induced fluorescence spectroscopy, the optical spectrum of PtB in the visible region between 455 and 520 nm has been studied. Gas-phase PtB molecule was produced by the reaction of diborane (B(2)H(6)) seeded in argon and laser ablated platinum atom. Seven vibrational bands of the Pt(11)B radical have been recorded and analyzed. The observation of Pt isotopic molecules and the Pt(10)B isotope confirmed the carrier of the bands. Two different transition systems, namely: the [20.2]3/2-X(2)Σ(+) and the [21.2]1/2-X(2)Σ(+) systems were identified. PtB was determined to have an X(2)Σ(+) ground state and the bond length, r(e), was determined to be 1.741 Å.

Electronic transitions of iridium monoxide: ground and low-lying electronic states.

The electronic transition spectrum of IrO in the spectral region between 448 and 650 nm has been recorded and analyzed using laser vaporization/reaction free jet expansion and laser induced fluorescence spectroscopy. The IrO molecule was produced by reacting laser-ablated iridium atoms with N(2)O seeded in argon. Five electronic transition systems, namely, the [17.6]2.5 - X(2)Δ(5/2), [17.8]2.5 - X(2)Δ(5/2), [21.5]2.5 - X(2)Δ(5/2), [22.0]2.5 - X(2)Δ(5/2), and [21.9]3.5 - Ω = 3.5 systems were identified. Transition lines of both the (191)IrO and (193)IrO isotopes were observed and analyzed. IrO was determined to have a X(2)Δ(5/2) ground state. A least squares fit of the measured rotational lines yielded molecular constants for the ground and low-lying electronic states. A molecular orbital energy level diagram has been used to help with the assignment of the observed electronic states.

Formation of polycyclic aromatic hydrocarbons from acetylene over nanosized olivine-type silicates.

The formation mechanism of polycyclic aromatic hydrocarbon (PAH) molecules in interstellar and circumstellar environments is not well understood although the presence of these molecules is widely accepted. In this paper, addition and aromatization reactions of acetylene over astrophysically relevant nesosilicate particles are reported. Gas-phase PAHs produced from exposure of acetylene gas to crystalline silicates using pulsed supersonic jet expansion (SJE) conditions were detected by time-of-flight mass spectrometry (TOF-MS). The PAHs produced were further confirmed in a separate experiment using a continuous flow fixed-bed reactor in which acetylene was introduced at atmospheric pressure. The gas-phase effluent and solutions of the carbonaceous compounds deposited on the nesosilicate particles were analyzed using gas chromatography-mass spectrometry (GC-MS). A mechanism for PAH formation is proposed in which the Mg(2+) ions in the nesosilicate particles act as Lewis acid sites for the acetylene reactions. Our studies indicate that the formation of PAHs in mixed-chemistry astrophysical environments could arise from acetylene interacting with olivine nano-particles. These nesosilicate particles are capable of providing catalytic centres for adsorption and activation of acetylene molecules that are present in the circumstellar environments of mass-losing carbon stars. The structure and physical properties of the particles were characterized by means of X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and high-resolution transmission electron microscopy (HRTEM) techniques.

Electronic transitions of cobalt monoboride.

Electronic transition spectrum of cobalt monoboride (CoB) in the visible region between 495 and 560 nm has been observed and analyzed using laser-induced fluorescence spectroscopy. CoB molecule was produced by the reaction of laser-ablated cobalt atom and diborane (B(2)H(6)) seeded in argon. Fifteen vibrational bands with resolved rotational structure have been recorded, which included transitions of both Co(10)B and Co(11)B isotopic species. Our analysis showed that the observed transition bands are ΔΩ = 0 transitions with Ω" = 2 and Ω" = 3 lower states. Four transition systems have been assigned, namely, the [18.1](3)Π(2)-X(3)Δ(2), the [18.3](3)Φ(3)-X(3)Δ(3), the [18.6]3- X(3)Δ(3), and the [19.0]2-X(3)Δ(2) systems. The bond length, r(o), of the X(3)Δ(3) state of CoB is determined to be 1.705 Å. The observed rotational lines showed unresolved hyperfine structure arising from the nuclei, which conforms to the Hund's case (a(ß)) coupling scheme. This work represents the first experimental investigation of the CoB spectrum.

Laser spectroscopy of NiI: new electronic states and hyperfine structure.

Two new electronic transition systems, namely, the [14.0](2)Phi(7/2)-Chi (2)Delta(5/2) and the [15.7](2)Phi(5/2)-Chi (2)Delta(5/2) transitions were observed and analyzed using laser vaporization/reaction supersonic free jet expansion and high resolution laser induced fluorescence spectroscopy. In addition, the (v, 0) bands with v=6-10 of the [14.6](2)Delta(5/2)-Chi (2)Delta(5/2) transition were found to be perturbed by the [15.7](2)Phi(5/2) state. The interaction between the [14.6](2)Delta(5/2) and the [15.7](2)Phi(5/2) states is evident in the progressive increase in hyperfine width of rotational lines of the [14.6](2)Delta(5/2)-X (2)Delta(5/2) transition as the vibrational quantum number increases. Deperturbation procedures were successfully applied to analyze the interaction between these two states. All observed spectra show partially resolved hyperfine structure, and the hyperfine width decreases rapidly as J increases suggested that the hyperfine structure conforms to the Hund's case a(beta) coupling scheme. Accurate molecular and hyperfine constants for the [14.0](2)Phi(7/2), the [14.6](2)Delta(5/2) and the [15.7](2)Phi(5/2) states were obtained and analyzed.

Laser spectroscopy of iridium monoboride.

High resolution laser induced fluorescence spectrum of IrB in the spectral region between 545 and 610 nm has been recorded and analyzed. Reacting laser-ablated iridium atoms with 1% B(2)H(6) seeded in argon produced the IrB molecule. This is the first experimental observation of the IrB molecule. Four vibronic transition bands, (v,0) with v=0-3 of an electronic transition system, have been observed. Spectra of all four isotopic molecules, (191)Ir(10)B, (193)Ir(10)B, (191)Ir(11)B, and (193)Ir(11)B, were recorded. Isotopic relationships confirmed the carrier of the spectra and the vibrational quantum number assignment. Preliminary analysis of rotational lines showed that these vibronic bands are with Omega' = 2 and Omega" = 3. The electronic transition identified is assigned as the [16.5](3)Pi(2)-X(3)Delta(3) system. Partially resolved hyperfine structure which conforms to the Hund's case a(beta) coupling scheme has been observed and analyzed. The bond length r(0) of the lower X(3)Delta(3) state of IrB was determined to be 1.7675 A.