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The hypothalamic–pituitary–adrenal axis is a tightly regulated system that represents one of the body’s mechanisms for responding to acute and chronic stress. Prolonged stress and/or inadequate regulation of the stress system can lead to a condition of chronic hypercortisolism or, in some cases, a blunted cortisol response to stress, contributing to insulin resistance, increased adiposity and type 2 diabetes mellitus. Moreover, acute and chronic stress can exacerbate or worsen metabolic conditions by supporting an inflammatory state and a tight relationship between stress, inflammation and adipose tissue has been reported and has been a growing subject of interest in recent years. We reviewed and summarized the evidence supporting hypothalamic–pituitary–adrenal axis dysregulation as an important biological link between stress, obesity, inflammation and type 2 diabetes mellitus. Furthermore, we emphasized the possible role of infectious-related stress such as SarsCov2 infection in adrenal axis dysregulation, insulin resistance and diabetes in a bidirectional link. Understanding and better defining the links between stress and obesity or diabetes could contribute to further definition of the pathogenesis and the management of stress-related complications, in which the HPA axis dysregulation has a primary role.

Objectives: During this ongoing pandemic of coronavirus disease 2019 (COVID-19), procalcitonin (PCT) assay has proven to be a useful tool in assisting clinicians to diagnose bacterial superinfection. However, in the absence of signs of infection or at resolution thereof, inappropriately and persistently high PCT may suggest and reveal the presence of other pathologies. We report a patient with acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia in whom persistence of initially elevated PCT during recovery prompted the diagnosis of medullary thyroid cancer (MTC). Case report: A 43- year-old man presented with a two-day history of fever, sneezing, sore throat and dry cough. Physical exam revealed decreased sounds and coarse crackles in both lung bases at auscultation. Medical history was positive for cognitive impairment since birth, arterial hypertension, systemic lupus erythematosus with nephritis. Initial studies included mild lymphocytopenia 650/µl (760 - 5000), D-Dimer 0.73 µg/ml (< 0.5), C reactive protein (CRP) of 62 mg/l (< 5) and PCT of 94 ng/ml (0.00 - 0.10). Positivity for SARS-Cov-2 RNA was detected and chest computerized tomography showed bilateral ground-glass opacities in the basilar lung zones and hyperdense and irregular foci in the thoracic vertebral bodies. Empirical antibiotic therapy was started and was maintained for seven days but, despite clinical improvement and the normalization of CRP, serum PCT was persistently high (84 ng/ml). Serum calcitonin (CTN) was 2120 pg/ml (normal up to 12 pg/ml). Neck ultrasound revealed inhomogeneously echogenic lymph nodes with small punctate calcifications and a non-homogeneous thyroid with multiple nodules. Cytological examination by fine needle aspiration and CTN measurement on washing liquid confirmed the suspicion of MTC. The patient underwent total thyroidectomy with bilateral cervical lymph node dissection. Histological analysis confirmed MTC of right thyroid lobe and metastasis at lymph nodes of the central right midneck area. Blood tests performed 48 hours after surgery showed a lowering of CTN (986 pg/mL) and PCT (16 ng/mL). A 6-months follow up showed persistent increased CTN and PCT levels (921 pg/ml and 16 ng/ml, respectively) while a (18)F-fluorodihydro-xyphenylalanine ((18)F-DOPA) PET did not reveal any suspicious fixations at thyroid lodge and cervical lymph node stations while multiple osteoblastic foci in the skeletal area were described. A close follow-up was planned with establishment of the results of RET gene analysis. Discussion: Although CTN is the gold standard biochemical parameter for the diagnosis and follow-up of MTC, PCT can be useful as a biochemical marker of MTC suspicion in patients with inflammatory conditions and persistently elevated PCT even after resolution. In the present CASE, high levels of PCT in a patient with Covid-19 pneumonia without signs of bacterial infection, allowed to diagnose MCT. Conclusion: In the absence of any other signs of infection, a complete clinical assessment, including neck palpation, CTN measurement and thyroid ultrasound should be performed in the presence of persistently elevated PCT.

Objectives During this ongoing pandemic of coronavirus disease 2019 (COVID-19), procalcitonin (PCT) assay has proven to be a useful tool in assisting clinicians to diagnose bacterial superinfection. However, in the absence of signs of infection or at resolution thereof, inappropriately and persistently high PCT may suggest and reveal the presence of other pathologies. We report a patient with acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia in whom persistence of initially elevated PCT during recovery prompted the diagnosis of medullary thyroid cancer (MTC). Case report A 43- year-old man presented with a two-day history of fever, sneezing, sore throat and dry cough. Physical exam revealed decreased sounds and coarse crackles in both lung bases at auscultation. Medical history was positive for cognitive impairment since birth, arterial hypertension, systemic lupus erythematosus with nephritis. Initial studies included mild lymphocytopenia 650/μl (760 – 5000), D-Dimer 0.73 μg/ml (< 0.5), C reactive protein (CRP) of 62 mg/l (< 5) and PCT of 94 ng/ml (0.00 – 0.10). Positivity for SARS-Cov-2 RNA was detected and chest computerized tomography showed bilateral ground-glass opacities in the basilar lung zones and hyperdense and irregular foci in the thoracic vertebral bodies. Empirical antibiotic therapy was started and was maintained for seven days but, despite clinical improvement and the normalization of CRP, serum PCT was persistently high (84 ng/ml). Serum calcitonin (CTN) was 2120 pg/ml (normal up to 12 pg/ml). Neck ultrasound revealed inhomogeneously echogenic lymph nodes with small punctate calcifications and a non-homogeneous thyroid with multiple nodules. Cytological examination by fine needle aspiration and CTN measurement on washing liquid confirmed the suspicion of MTC. The patient underwent total thyroidectomy with bilateral cervical lymph node dissection. Histological analysis confirmed MTC of right thyroid lobe and metastasis at lymph nodes of the central right midneck area. Blood tests performed 48 hours after surgery showed a lowering of CTN (986 pg/mL) and PCT (16 ng/mL). A 6-months follow up showed persistent increased CTN and PCT levels (921 pg/ml and 16 ng/ml, respectively) while a (18)F-fluorodihydro-xyphenylalanine ((18)F-DOPA) PET did not reveal any suspicious fixations at thyroid lodge and cervical lymph node stations while multiple osteoblastic foci in the skeletal area were described. A close follow-up was planned with establishment of the results of RET gene analysis. Discussion Although CTN is the gold standard biochemical parameter for the diagnosis and follow-up of MTC, PCT can be useful as a biochemical marker of MTC suspicion in patients with inflammatory conditions and persistently elevated PCT even after resolution. In the present CASE, high levels of PCT in a patient with Covid-19 pneumonia without signs of bacterial infection, allowed to diagnose MCT. Conclusion In the absence of any other signs of infection, a complete clinical assessment, including neck palpation, CTN measurement and thyroid ultrasound should be performed in the presence of persistently elevated PCT.

Although trichoscopic criteria indicative of disease severity and inflammatory activity have been recently proposed, the potential use of reflectance confocal microscopy (RCM) in the evaluation of the inflammatory stage of FD has never been published to date. Our study investigated RCM features of 14 patients with a histopathological diagnosis of FD, evaluating clinical and trichoscopic findings. RCM findings were divided into 2 main patterns: “follicular” and “interfollicular.” Our results suggest a potential role for RCM as a noninvasive, fast technique for a complementary investigation in the diagnostic process, as well as in the therapeutic management decision.

Psoriasis and alopecia areata (AA) are among the most prevalent autoimmune inflammatory diseases, affecting 1% to 4%1 and 0.1% to 0.2%2 of the worldwide population, respectively. Alopecia, decreased hair density, thin hair, and an increased number of dystrophic bulbs have been described in the context of the psoriatic plaques and thought to be causally associated with psoriasis.3, 4 Nevertheless, most patients with psoriatic alopecia experience complete regrowth of scalp hair after successful treatment of their scalp psoriasis.3 Among systemic treatments, methotrexate and retinoids are known to be associated with alopecia,5, 6 whereas there are conflicting results about anti–tumor necrosis factor (TNF) and alopecia areata.7, 8 Few epidemiologic studies found that patients with psoriasis are at greater risk of AA development.9, 10 It is estimated that patients with psoriasis have a 2.5-fold higher risk of AA development and are more likely to have at least 1 other autoimmune disease (odds ratio [OR], 1.6; confidence interval [CI], 1.5-1.7) or even 2 other autoimmune diseases (OR, 1.9; CI, 1.6-2.4).9 A recent retrospective study found that vitiligo was the most frequent skin autoimmune disease associated with psoriasis, followed by AA and chronic urticaria.7, 10 The most frequent association seems to be scalp psoriasis and AA.7, 9 Although some investigators found that psoriatic arthritis (PsA) might represent a protective factor,9, 10 others found that patients with AA are more frequently affected by either psoriasis or PsA.11, 12 Several studies also found a high prevalence of comorbid conditions as atopic dermatitis, diabetes, thyroiditis, celiac disorder, psoriasis, and PsA among individuals with AA.11, 12 We describe 4 patients affected by psoriasis and concomitant AA, emphasizing the clinical and dermoscopic characteristics, and correlation of the hair loss with antipsoriatic treatment. The collected data are summarized in Table I. Table I Summarized clinical features of the reported patients

Aberrant CGG trinucleotide amplification within the FMR1 gene, which spans approximately 38 Kb of genomic DNA is almost always what leads to fragile X syndrome (FXS). However, deletions of part or the entire FMR1 gene can also cause FXS. Both CGG amplification-induced silencing and deletions result in the absence of the FMR1 gene product, FMRP. Here, we report a rare case of germinal mosaicism of a deletion encompassing approximately 300 Kb of DNA, which by removing the entire FMR1 gene led to FXS. The male proband, carrying the deletion, presented in clinic with the typical features of FXS. His mother was analyzed by FISH on metaphase chromosomes with cosmid probe c22.3 spanning the FMR1 locus, and she was found not to carry the deletion on 30 analyzed cells from peripheral blood lymphocytes. Prenatal examination of the mother's third pregnancy showed that the male fetus also had the same deletion as the proband. Following this prenatal diagnosis, FISH analysis in the mother was expanded to 400 metaphases from peripheral lymphocytes, and a heterozygous FMR1 deletion was found in three. Although this result could be considered questionable from a diagnostic point of view, it indicates that the deletion is in the ovary's germinal cells.

A reduction in bone mineral density (BMD) is common in primary hyperparathyroidism (PHPT), above all at cortical sites. Guidelines for the management of asymptomatic PHPT (aPHPT) recommend a BMD evaluation at the lumbar spine, hip, and forearm. Surgery is recommended for patients with a T-score less than or equal to -2.5 at any of these sites. However, a BMD evaluation at the forearm is not routinely performed.To evaluate the impact of measuring forearm BMD in the clinical management of aPHPT.We retrospectively reviewed a prospective database of 172 patients with aPHPT, selecting the 116 patients in whom a dual x-ray absorptiometry (DXA) scan had been performed at all 3 sites.Seventy-four out of 116 patients had a densitometric diagnosis of osteoporosis (OP) at any site, and the forearm was the only site involved in 13/74 (group A, 17.6% of osteoporotic patients and 11.2% of the whole aPHPT cohort). Patients belonging to group A were significantly older than the other aPHPT patients, whereas no difference was found in biochemical measurements. Six out of 13 patients belonging to group A (5.2% of the whole aPHPT cohort) fulfilled surgical criteria based only on a forearm T-score.DXA at 3 sites revealed OP at the forearm, but not at the other sites, in 11.2% of aPHPT patients. Half of these cases met surgical criteria based on this one factor alone. These patients did not show any clinical (except age) or biochemical differences from the other patients. The implementation of forearm DXA increases the rate of patients with aPHPT meeting surgical criteria.

Alopecia Areata (AA) is an organ-specific autoimmune disorder that targets anagen phase hair follicles. The course is unpredictable and current available treatments have variable efficacy. Nowadays, there is relatively little evidence on treatment of AA from well-designed clinical trials. Moreover, none of the treatments or devices commonly used to treat AA are specifically approved by the Food and Drug Administration (FDA). The Italian Study Group for Cutaneous Annexial Disease of the Italian Society of dermatology (SIDeMaST) proposes these Italian guidelines for diagnosis and treatment of Alopecia Areata deeming useful for the daily management of the disease. This article summarizes evidence-based treatment associated with expert-based recommendations.

Nail toxicities, such as paronychia and pyogenic granuloma-like lesions, are well-recognized side effects of epidermal growth factor receptor inhibitor (EGFR-I) therapy that can significantly impair patient's quality of life and compliance to anticancer treatment. Numerous therapeutic options are available, with variable rates of success. Recently, topical β-blockers have emerged as a novel, non-invasive treatment strategy. We tested the effectiveness of topical timolol 0.5% gel, twice daily, under occlusion for 30 days, on paronychia and periungual pyogenic granuloma-like lesions in 9 patients being treated with EGFR-I. We also reviewed the available literature on this topic, which is the use of topical β-blockers in the management of EGFR-I-induced nail toxicities. We assessed 25 lesions consistent with the diagnosis of EGFR-I-induced pyogenic granuloma-like lesions and paronychia (21 diagnosed as pyogenic granuloma-like, and four as paronychia). Thirteen of the 25 lesions achieved complete resolution, 9/25 reached at least improvement, and only 3/25 did not respond to the intervention. As for the review, four papers met the scope of our research. The results confirmed at least partial benefit in the majority of treated patients. Among current strategies, high-potency topical corticosteroids are a well-known treatment option especially for paronychia, targeting the inflammatory component of such lesions; nevertheless, the management of pyogenic granuloma-like lesion is often more complex and the success rate is variable. Nail plate avulsion and phenol chemical matricectomy are not highly effective and display some degree of invasiveness. Topical β-blockers seem to be promising alternatives, especially in fragile cancer patients who may be unsuitable candidates for an invasive procedure.

We use two-dimensional electronic spectroscopy (2DES) to disentangle the separate electron and hole relaxation pathways and dynamics of CdTe nanorods on a sub-100 fs time scale. By simultaneously exciting and probing the first three excitonic transitions (S1, S2, and S3) and exploiting the unique combination of high temporal and spectral resolution of 2DES, we derive a complete picture for the state-selective carrier relaxation. We find that hot holes relax from the 1Σ3/2 to the 1Σ1/2 state (S2 → S1) with 30 ± 10 fs time constant, and the hot electrons relax from the Σ′ to the Σ state (S3 → S1) with 50 ± 10 fs time constant. This observation would not have been possible with conventional transient absorption spectroscopy due to the spectral congestion of the transitions and the very fast relaxation time scales.

We present a joint experimental and theoretical study of the early stage dynamics of photoexcited charges in a prototypical organic/inorganic interface. By using femtosecond pump probe experiments we compared the photophysic of a layer-by-layer hybrid structure obtained by alternating CdSe nanocrystals and poly(p-styrenesulphonic acid) and the same CdSe nanocrystals capped with hexadec-ylamine and stearic acid diluted in solutions. While in the LBL structure it is dear the appearance of a long-lived charged state, no evidence of this is instead found in the diluted solutions. Density functional calculations indicate that these states are localized dose to the nanoparticle surface, and that electrons and holes are separated across the hybrid interface, pointing out the effects of surfactant capping molecules on the optoelectronic properties of the interface. Our combined approach, allowing for unique access to the photoexcited electronic structure, opens the possibility to the fine tailoring of hybrid organic/semiconducting layers for photovoltaic applications.

The simple solution processability at room temperature exposes lead halide perovskite semiconductors to a non-negligible level of unintentional structural and chemical defects. Ascertained that their primary optoelectronic properties meet the requirement for high efficiency optoelectronic technologies, a lack of knowledge about the nature of defects and their role in the device operation currently is a major challenge for their market-scale application due to the issues with stability and reliability. Here, we use excitation correlation photoluminescence (ECPL) spectroscopy to investigate the recombination dynamics of the photogenerated carriers in lead bromide perovskites and quantitatively describe the carrier trapping dynamics within a generalization of the Shockley-Read-Hall formalism. The superior sensitivity of our spectroscopic tool to the many-body interactions enables us to identify the energetics of the defects. In fact, in the case of polycrystalline films, depending on the synthetic route, we demonstrate the presence of both deep and shallow carrier traps. The shallow defects, which are situated at about 20 meV below the conduction band, dope the semiconductor, leading to a substantial enhancement of the photoluminescence quantum yield despite carrier trapping. At excitation densities relevant for lasing, we observe breakdown of the rate-equation model, indicating a buildup of a highly correlated regime of the photocarrier population that suppresses the nonradiative Auger recombination. Furthermore, we demonstrate that colloidal nanocrystals represent virtually defect-free systems, suffering from nonradiative quenching only due to subpicosecond Auger-like interactions at high excitation density. By correlating the fabrication conditions to the nonradiative loss channels, this work provides guidelines for material engineering towards superior optoelectronic devices.

The simple solution processability at room temperature exposes lead halide perovskite semiconductors to a non-negligible level of unintentional structural and chemical defects. Ascertained that their primary optoelectronic properties meet the requirement for high efficiency optoelectronic technologies, a lack of knowledge about the nature of defects and their role in the device operation currently is a major challenge for their market-scale application due to the issues with stability and reliability. Here, we use excitation correlation photoluminescence (ECPL) spectroscopy to investigate the recombination dynamics of the photogenerated carriers in lead bromide perovskites and quantitatively describe the carrier trapping dynamics within a generalization of the Shockley–Read–Hall formalism. The superior sensitivity of our spectroscopic tool to the many-body interactions enables us to identify the energetics of the defects. In fact, in the case of polycrystalline films, depending on the synthetic route, we demonstrate the presence of both deep and shallow carrier traps. The shallow defects, which are situated at about 20 meV below the conduction band, dope the semiconductor, leading to a substantial enhancement of the photoluminescence quantum yield despite carrier trapping. At excitation densities relevant for lasing, we observe breakdown of the rate-equation model, indicating a buildup of a highly correlated regime of the photocarrier population that suppresses the nonradiative Auger recombination. Furthermore, we demonstrate that colloidal nanocrystals represent virtually defect-free systems, suffering from nonradiative quenching only due to subpicosecond Auger-like interactions at high excitation density. By correlating the fabrication conditions to the nonradiative loss channels, this work provides guidelines for material engineering towards superior optoelectronic devices.

Context: The recent Third International Workshop on the Management of Asymptomatic Primary Hyperparathyroidism (PHPT) set 60 ml/min as the precise level of glomerular filtration rate (GFR) below which surgery is recommended because it is considered a threshold of concern in patients with PHPT. Objective: The aim of the study was to investigate the relationship between different stages of renal insufficiency and PTH levels in PHPT patients. Design: We conducted a cross-sectional study. Patients and Methods: We studied 294 consecutive PHPT patients. Biochemical evaluation included total and ionized serum calcium, phosphate, creatinine, immunoreactive intact PTH, and 25-hydroxyvitamin D3 levels in the fasting state. GFR was assessed with the Modification of Diet in Renal Disease Study formula. Results: The mean GFR of the whole group of PHPT patients was 92.3 ± 31.6 ml/min · 1.73 m2. The patients were divided into four groups according to National Kidney Foundation Disease Outcomes Quality Initiative (K/DOQI) guidelines: group 1 with normal or increased GRF (>90 ml/min · 1.73 m2; n = 153); group 2 with mild decreased GFR (60–89 ml/min · 1.73 m2; n = 90); group 3 with moderately decreased GFR (30–59 ml/min · 1.73 m2; n = 45); and group 4 with severely decreased GFR ( Conclusion: In our series of PHPT patients, only a severe impairment of GFR was characterized by a further PTH increase. These findings challenge the concept of a PTH elevation below the threshold of 60 ml/min of GFR. In a large series of contemporary PHPT patients, only a severe impairment of glomerular filtration rate (i.e.

Decreased renal function has been consistently included among factors prompting recommendation for surgery in primary hyperparathyroidism (PHPT). However, most retrospective studies addressing this issue did not show an improvement in renal function after parathyroidectomy (PTX). The aim of this study was to investigate changes in renal function after PTX in PHPT patients subdivided according to renal function at diagnosis.This was a retrospective cross-sectional study.We studied 109 consecutive PHPT patients before and after PTX. Biochemical evaluation included fasting total and ionized serum calcium, phosphate, creatinine, immunoreactive intact PTH, and 25-hydroxyvitamin D3 levels. Glomerular filtration rate (GFR) was assessed with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.Mean (± SD) CKD-EPI estimated GFR (eGFR) at diagnosis was 82.4 ± 19.3 mL/min/1.73 m(2) (median, 84.8 mL/min/1.73 m(2); interquartile range, 68.5-94.2 mL/min/1.73 m(2)). Patients with eGFR equal to or higher than 60 mL/min/1.73 m(2) (group 1, n = 95) were significantly younger than patients with eGFR lower than 60 mL/min/1.73 m(2) (group 2, n = 14; P.0003). After PTX, eGFR did not change in patients of group 2 (P = .509), whereas it was significantly reduced in patients of group 1 (P.0002). The difference in eGFR between baseline and post-PTX values was correlated negatively with baseline serum creatinine (R = -0.27; P = .0052) and positively with baseline CKD-EPI eGFR (R = 0.32; P = .00062). At multiple regression analysis, only systolic blood pressure and baseline CKD-EPI eGFR were independent predictors of GFR variation.Surgical cure of PHPT halts renal function deterioration in patients with coexisting renal disease. Our study thus supports the indication for surgery in patients with eGFR less than 60 mL/min/1.73 m(2), as recommended by current guidelines. Moreover, our data show that presurgical renal function is a relevant predictor of renal function after PTX.

We present a spectroscopic investigation on a new hyperbranched cadmium selenide nanocrystals (CdSe NC)/poly(3-hexylthiophene) (P3HT) blend, a potentially good active component in hybrid photovoltaics. Combined ultrafast transient absorption spectroscopy and morphological investigations by means of an ultrafast confocal microscope reveal a strong influence of the complex local structure on the photogenerated carrier dynamics. In particular, we map the electron-transfer process across the hybrid NC/polymer interface, and we reveal that charge separation occurs through a preferential pathway from the CdSe nanobranches to the P3HT chains. Efficient charge generation at the distributed heterojunction is also confirmed by scanning kelvin probe force microscopy measurements.

Ghrelin stimulates appetite and plays a role in the neuroendocrine response to energy balance variations. Ghrelin levels are inversely associated with body mass index (BMI), increased by fasting and decreased by food intake, glucose load, insulin, and somatostatin. Ghrelin levels are reduced in obesity, a condition of hyperinsulinism, reduced GH secretion, and hypothalamus-pituitary-adrenal axis hyperactivity. We studied the endocrine and metabolic response to acute ghrelin administration (1.0 μg/kg iv) in nine obese women [OB; BMI (mean ± sd) 36.3 ± 2.3 kg/m2] and seven normal women (NW; BMI 20.3 ± 1.7 kg/m2). Basal ghrelin levels in NW were higher than in OB (P < 0.05). In NW, ghrelin increased (P < 0.05) GH, prolactin (PRL), ACTH, cortisol, and glucose levels but did not modify insulin. In OB, ghrelin increased (P < 0.01) GH, PRL, ACTH, and cortisol levels. The GH response to ghrelin in OB was 55% lower (P < 0.02) than in NW, whereas the PRL, ACTH, and cortisol responses were similar. In OB, ghrelin increased glucose and reduced insulin (P < 0.05). Thus, obesity shows remarkable reduction of the somatotroph responsiveness to ghrelin, suggesting that ghrelin hyposecretion unlikely explains the impairment of somatotroph function in obesity. On the other hand, in obesity ghrelin shows preserved influence on PRL, ACTH, and insulin secretion as well as in glucose levels.

To clarify the impairment of the GH/IGF-I axis in obstructive sleep apnea syndrome (OSAS), in 13 adult male patients with OSAS (OSA) as well as 15 weight-matched patients with simple obesity (OB) and 10 normal lean male subjects (NS), we studied: 1) the GH response to GHRH (1 micro g/kg iv) plus arginine (30 g iv); and 2) the IGF-I and IGF binding protein-3 responses to a very low dose recombinant human (rh)GH treatment (5.0 microg/kg sc per day for 4 d). The GH response to arginine plus GHRH in OSA was lower than in OB (P < 0.05), which in turn was lower than in NS (P < 0.001). Basal IGF-I levels in OSA were lower than in OB (P < 0.05), which in turn were lower than in NS (P < 0.03). As opposed to OB and NS, in OSA a very low rhGH dose did not affect IGF-I. Adjusting for age and basal values, rhGH-induced IGF-I rise in OSA was lower than in OB (P < 0.01). IGF binding protein-3, glucose, and insulin levels in the three groups were not modified by rhGH. OSA show a more marked impairment of the maximal secretory capacity of somatotroph cells together with reduced IGF-I sensitivity to rhGH stimulation. These findings suggest that OSAS is connoted by a concomitant impairment of GH secretion and sensitivity.

OBJECTIVE: Reduction of growth hormone (GH) secretion in obesity probably reflects neuroendocrine and metabolic abnormalities. Even short-term fasting stimulates GH secretion and distinguishes normal from hypopituitary subjects with growth hormone deficiency (GHD). Marked weight loss improves GH secretion in obesity but the effect of fasting is controversial. We studied the effects of a 36 h fasting on the GH/IGF-I axis and metabolic parameters in obesity. SUBJECTS: We studied nine obese patients (OB; three male and six female; age, 29.2±4.8; range, 18–59 y; body mass index (BMI), 43.4±2.7 kg/m2; WHR, 0.9±0.1). Fifteen normal subjects (NS; eight male and seven female 28.9±0.6, 25–35 y; 21.6±0.4 kg/m2) and 10 adult hypopituitary patients with severe GH deficiency (GHD; seven male and three female; 37.6±2.3, 29–50 y; 24.5±1.0 kg/m2; GH peak

OBJECTIVE: To verify the hypothesis of an increased sensitivity to GH in obesity (OB) and Cushing's syndrome (CS). DESIGN: We studied the effects of short-term administration of low-dose rhGH on circulating IGF-I levels in patients with simple OB or CS and in normal subjects (NS). METHODS: Nineteen women with abdominal OB aged (mean +/- s.e.m.) 38.2+/-3.1 years, body mass index 40.7+/-2.5 kg/m(2), waist to hip ratio 0.86+/-0.02, ten with CS (50.4+/-4.2 years, 29.7 +/- 3.3 kg/m(2)) and 11 NS (35.0+/-3.6 years, 20.5+/-0.5 kg/m(2)) underwent s.c. administration of 5 microg/kg per day rhGH at 2200 h for four days. Serum IGF-I, IGF-binding protein-3 (IGFBP-3), GH-binding protein (GHBP), insulin and glucose levels were determined at baseline and 12 h after the first and the last rhGH administration. RESULTS: Basal IGF-I levels in NS (239.3+/-22.9 microg/l) were similar to those in OB (181.5+/-13.7 microg/l) and CS (229.0+/-29.1 microg/l). Basal IGFBP-3, GHBP and glucose levels in NS, OB and CS were similar while insulin levels in NS were lower (P

Circulating GH levels are reduced in obesity due to true reduction of the 24-h GH production rate. GH insufficiency in obesity might reflect neuroendocrine abnormalities and/or alterations in peripheral hormones and metabolic factors. The somatotroph response to provocative stimuli including GHRH is markedly blunted in obese patients. However, the somatotroph responsiveness to GHRH in obesity shows also peculiar refractoriness to the inhibitory effect of glucose load. In this present study we aimed at verifying the effect of low dose rhIGF-I (20μ g/kg, sc, at 0 min) on the GH response to GHRH (1 μg/kg, iv, at 180 min) in obesity. With this goal in mind, six obese women with abdominal adiposity [OB; age (mean ± sem), 32.3± 4.4 yr; body mass index, 32.8 ± 2.3 kg/m2] were studied. The effects of recombinant human insulin-like growth factor I (rhIGF-I) administration on circulating total IGF-I, insulin, and glucose levels were also evaluated. The results in OB were compared with those recorded in age-matched ...

We present a self-consistent treatment of the electron-hole correlations in optically excited quantum wires within the ladder approximation, and using a contact potential interaction. The limitations of the ladder approximation to the excitonic low-density region are largely overcome by the introduction of higher order correlations through self consistency. We show relevance of these correlations in the low-temperature emission, even for high density relevant in lasing, when large gain replaces excitonic absorption., 4 paes 3 figures

Rod-shaped CdTe–Cu2−xTe nano-heterostructures with tunable dimensions of both sub-units and a type II band alignment were prepared by Cd2+/Cu+ cation exchange. The light absorption properties of the heterostructures are dominated by the excitonic and plasmonic contributions arising, respectively, from the CdTe and the Cu2−xTe sub-units. These results were confirmed over a wide range of sub-unit length fractions through optical modelling based on the discrete dipole approximation (DDA). Although assuming electronically independent sub-units, our modelling results indicate a negligible ground state interaction between the CdTe exciton and the Cu2−xTe plasmon. This lack of interaction may be due to the low spectral overlap between exciton and plasmon, but also to localization effects in the vacancy-doped sub-unit. The electronic interaction between both sub-units was evaluated with pump-probe spectroscopy by assessing the relaxation dynamics of the excitonic transition. In particular, the CdTe exciton decays faster in the presence of the Cu2−xTe sub-unit, and the decay gets faster with increasing its length. This points towards an increased probability of Auger mediated recombination due to the high carrier density in the Cu2−xTe sub-unit. This indication is supported through length-fraction dependent band structure calculations, which indicate a significant leakage of the CdTe electron wavefunction into the Cu2−xTe sub-unit that increases along with the shortening of the CdTe sub-unit, thus enhancing the probability of Auger recombination. Therefore, for the application of type II chalcogenide–chalcogenide heterostructures based on Cu and Cd for photoenergy conversion, a shorter Cu-based sub-unit may be advantageous, and the suppression of high carrier density within this sub-unit is of high importance.

Glucose load has a biphasic effect on GH secretion. In fact, in normal subjects, glucose load has a prompt inhibitory and a late stimulatory effect on both spontaneous and GHRH-induced GH levels. The mechanism underlying the inhibitory effect is probably mediated by the increase in hypothalamic somatostatin, whereas that underlying the stimulatory effect is unclear. On the other hand, in obesity, a reduced somatotrope responsiveness to all GH secretagogues is well known, whereas recently, we found that glucose load, but not pirenzepine and somatostatin, fails to inhibit the GHRH-induced GH rise. Thus, the inhibitory effect of hyperglycemia on GH secretion is selectively lacking in obesity. The aim of the present study was to verify whether in obesity the late stimulatory effect of glucose on GH secretion is preserved. We studied 15 female obese patients (OB; age, 33.9 ± 2.6 yr; body mass index, 36.4 ± 1.5 kg/m2; waist/hip ratio, 0.9 ± 0.1) and 12 normal female subjects (NS; 26.5 ± 1.0 yr; 21.4± 0.3 kg/m2)...

Heavily-doped semiconductor nanocrystals characterized by a tunable plasmonic band have been gaining increasing attention recently. Herein, we introduce this type of materials focusing on their structural and photo physical properties. Beside their continuous-wave plasmonic response, depicted both theoretically and experimentally, we also review recent results on their transient, ultrafast response. This was successfully interpreted by adapting models of the ultrafast response of gold nanoparticles., 20 pages review paper, 15 figures

Aqueous dispersions containing TiO2 nanoparticles and hydrophilic poly(2-ethyl-2-oxazoline) allow the preparation of highly transparent nanocomposites containing up to 44 wt% of TiO2. Transmission Electron Microscopy (TEM) images indicate that the nanoparticles are homogeneously distributed in the polymeric matrix with no significant agglomeration. Nanocomposite films remain highly transparent to visible light, absorb the ultraviolet (UV) radiation, and their refractive indices can be regulated in the range from 1.52 to 1.65 by the content of TiO2 nanoparticles. While specular gloss measurements reveal an increase of the root-mean-square (RMS) surface roughness with TiO2 content, distinctness-of-image gloss measurements demonstrate that it does not negatively affect the image information carried by the underlying layer. © 2012 The Royal Society of Chemistry.

Cushing's syndrome may remain unrecognized among patients referred for metabolic syndrome; thus, a proactive screening has been suggested in certain patient populations with features of the disorder. However, conflicting data have been reported on the prevalence of Cushing's syndrome in patients with type 2 diabetes.Our aim was to evaluate the prevalence of unsuspected Cushing's syndrome among outpatients with type 2 diabetes.This was a cross-sectional prospective study in 24 diabetes clinics across Italy.Between June 2006 and April 2008, 813 patients with known type 2 diabetes without clinically overt hypercortisolism were evaluated. Follow-up of the study was closed in September 2010. Patients were not selected for characteristics conferring a higher pretest probability of hypercortisolism. Patients underwent a first screening step with the 1-mg overnight dexamethasone suppression test.Forty patients failed to suppress serum cortisol less than 5.0 μg/dl (138 nmol/liter) and underwent a standard 2-d, 2-mg dexamethasone suppression test, after which six patients (0.6% of the overall series) failed to suppress cortisol less than 1.8 μg/dl (50 nmol/liter), receiving a definitive diagnosis of Cushing's syndrome that was adrenal dependent in five patients. Four patients were cured, being able to discontinue, or reduce, the glucose-lowering agents.The present data do not support widespread screening of patients with type 2 diabetes for Cushing's syndrome; however, the disorder is less rare than previously thought when considering epidemiology of type 2 diabetes. Our results support a case-finding approach in patients with uncontrolled diabetes and hypertension despite appropriate treatment.

We study the convergence and the stability of fictitious dynamical methods for electrons. first, we show that a particular damped second-order dynamics has a much faster rate of convergence to the ground state than first-order steepest-descent algorithms while retaining their numerical cost per time step. Our damped dynamics has efficiency comparable to that of conjugate gradient methods in typical electronic minimization problems. Then, we analyze the factors that limit the size of the integration time step in approaches based on plane-wave expansions. The maximum allowed time step is dictated by the highest frequency components of the fictitious electronic dynamics. These can result either from the larger wave vector components of the kinetic energy or from the small wave vector components of the Coulomb potential giving rise to the so called charge sloshing problem. We show how to eliminate large wave vector instabilities by adopting a preconditioning scheme in the context of Car-Parrinello ab initio molecular-dynamics simulations of the ionic motion. We also show how to solve the charge sloshing problem when this is present. We substantiate our theoretical analysis with numerical tests on a number of different silicon and carbon systems having both insulating and metallic character.

Background: The impairment of renal function can affect the clinical presentation of primary hyperparathyroidism (PHPT), increasing cardiovascular morbidity, fracture rate, and the risk of mortality. Aim: The aim of the study was to assess the differences in bone status in a series of consecutive patients affected by PHPT without overt renal failure at diagnosis grouped according to creatinine clearance (Ccr). Methods: A total of 161 consecutive patients with PHPT were studied. They were divided into two groups based on Ccr. Group A had Ccr 70 ml/min or less (n = 49), and group B had Ccr greater than 70 ml/min (n = 112). PTH, total and ionized serum calcium; urinary calcium and phosphate; serum 25-hydroxyvitamin D3; serum and urinary bone markers; lumbar, forearm, and femoral bone mineral density (BMD) were evaluated. Results: Patients in group A were older than those in group B (P < 0.0001). PTH levels did not differ in the two groups, whereas both urinary calcium and phosphorus were lower in group A than group B (P < 0.01). Lower BMD was evident in group A at lumbar spine (P < 0.002), forearm (P < 0.0001), and femur (P < 0.01). In asymptomatic PHPT, those with Ccr 70 ml/min or less had lower forearm BMD than patients with higher Ccr (P < 0.00001). When adjusting for age and body mass index in PHPT, BMD at each site persisted being lower (P < 0.05) in group A than group B. In all PHPT subjects, Ccr (beta = 0.29, P < 0.0005), age (beta = −0.27, P < 0.00001), and PTH levels (beta = −0.27, P < 0.0005) were all independently associated with forearm BMD. Conclusions: In PHPT a slight decrease in renal function is associated with more severe BMD decrease, independent of age, body mass index, and PTH levels. This association is also present in asymptomatic PHPT and strengthens the National Institutes of Health recommendations for surgery in patients with mild PHPT.

Based on density-functional perturbation theory we have computed the photoelastic tensor of a model of sodium silicate glass of composition ${({\mathrm{Na}}_{2}\mathrm{O})}_{0.25}{(\mathrm{Si}{\mathrm{O}}_{2})}_{0.75}$ (NS3). The model (containing 84 atoms) is obtained by quenching from the melt in combined classical and Car-Parrinello molecular dynamics simulations. The calculated photoelastic coefficients are in good agreement with experimental data. In particular, the calculation reproduces quantitatively the decrease of the photoelastic response induced by the insertion of Na, as measured experimentally. The extension to NS3 of a phenomenological model developed in a previous work for pure $a\text{\ensuremath{-}}\mathrm{Si}{\mathrm{O}}_{2}$ indicates that the modulation upon strain of other structural parameters besides the $\mathrm{Si}\mathrm{O}\mathrm{Si}$ angles must be invoked to explain the change in the photoelastic response induced by Na.

Based on density-functional perturbation theory we have computed from first principles the photoelastic tensor of few crystalline phases of silica at normal conditions and high pressure (quartz, $\alpha$-cristobalite, $\beta$-cristobalite) and of models of amorphous silica (containig up to 162 atoms), obtained by quenching from the melt in combined classical and Car-Parrinello molecular dynamics simulations. The computational framework has also been checked on the photoelastic tensor of crystalline silicon and MgO as prototypes of covalent and ionic systems. The agreement with available experimental data is good. A phenomenological model suitable to describe the photoelastic properties of different silica polymorphs is devised by fitting on the ab-initio data., Comment: ten figures