Nonlinear Carrier Interactions in Lead Halide Perovskites and the Role of Defects.

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.

Clinical predictors of nonresponse to anti-TNF-α agents in psoriatic patients: A retrospective study.

Although the heterogeneity of the therapeutic response to TNF-α blockers seems to be mainly due to genetic factors, several studies showed that a range of factors may influence it. The aim of our study was to investigate the impact of patients' demographic and clinical characteristics on primary response to an anti-TNF-α therapy in psoriatic patients. We retrospectively examined the relationship between various clinical and demographic features and response to treatment with etanercept, adalimumab, and infliximab, evaluated as PASI75 and average PASI improvement at weeks 12, 16, and 14, respectively. We analyzed data obtained from 199 patients. A better response to the treatment was significantly associated with male gender (OR = 2.59), coexistence of psoriatic arthritis (OR = 1.97), and PASI ≤15 at baseline (OR = 0.91). The present study supports that some clinical factors may be potential predictors of response to anti-TNF-α agents in psoriatic patients.

VITAMIN D DEFICIENCY DOES NOT AFFECT THE LIKELIHOOD OF PRESURGICAL LOCALIZATION IN ASYMPTOMATIC PRIMARY HYPERPARATHYROIDISM.

OBJECTIVE: Vitamin D deficiency (VDD) was previously associated with larger adenoma size in primary hyperparathyroidism (PHPT), but this topic was not addressed in patients with the mild/asymptomatic form of the disease (aPHPT). METHODS: We retrospectively retrieved from our series of patients affected by PHPT, 96 consecutive subjects with aPHPT in whom 25-hydroxyvitamin D (25OHD) levels had been assayed and compared those results with localizing imaging studies. RESULTS: Twenty-five of 96 patients had VDD (25OHD <20 ng/mL), but positive ultrasound and scintigraphic studies were not different between patients with and without VDD (52.3% versus 55.7% and 42.9% versus 52.4%, respectively). Upon logistic regression analysis, after adjusting for different variables, including the presence of goiter, VDD was not an independent predictor of localization by imaging studies. CONCLUSION: VDD does not affect the likelihood of positive pre-operative imaging in aPHPT and the consequent surgical decisions.

KDIGO CATEGORIES OF GLOMERULAR FILTRATION RATE AND PARATHYROID HORMONE SECRETION IN PRIMARY HYPERPARATHYROIDISM.

OBJECTIVE: The recent Fourth Workshop on the Management of Asymptomatic primary hyperparathyroidism (PHPT) maintained the threshold of 60 mL/min for decreased renal function, below which surgery is recommended. This study investigated the relationship between different stages of renal insufficiency and parathyroid hormone (PTH) levels in an updated case series of PHPT patients. METHODS: This was a retrospective, cross-sectional study involving 379 consecutive PHPT patients. Biochemical evaluation included total and ionized serum calcium, phosphate, creatinine, immunoreactive intact PTH, and 25-hydroxyvitamin D3 (25[OH]D3) levels in the fasting state. Glomerular filtration rate (GFR) was estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. RESULTS: Mean CKD-EPI estimated GFR was 81.9 ± 20.3 mL/min/1.73 m(2), and median GFR was 84.0 mL/min/1.73 m(2) (interquartile range, 26.8 mL/min/1.73 m(2)). The patients were divided into 5 groups according to the Kidney Disease: Improving Global Outcomes 2012 guidelines: group 1 with normal or increased GFR (>90 mL/min/1.73 m(2)); group 2 with mild GFR decrease (60 to 89 mL/min/1.73 m(2)); group 3a with mild to moderate GFR decrease (45 to 59 mL/min/1.73 m(2)); group 3b with moderate to severe GFR decrease (30 to 44 mL/min/1.73 m(2)); and group 4 with severe GFR decrease (<30 mL/min/1.73 m(2)). Among the 5 groups of patients, serum calcium levels were different (P = .025), whereas 25(OH)D3 levels were not (P = .36). PTH levels were comparable across groups 1 through 3a, but they were significantly higher in groups 3b and 4 (P<.0001). CONCLUSION: In our series of PHPT patients, PTH levels did not rise as a result of renal impairment until GFR decreased below 45 mL/min/1.73 m(2).

Relationship between insulin sensitivity and bone mineral density in primary hyperparathyroidism.

INTRODUCTION: Evidence of crosstalk between bone and insulin metabolism has been identified. In primary hyperparathyroidism (PHPT), scant data exist on this relationship. AIM: To evaluate the relationship between insulin levels or sensitivity and bone mineral density (BMD) in PHPT. SUBJECT AND METHODS: Two hundred and sixty-seven patients with PHPT without known diabetes mellitus were studied. Fasting blood glucose and insulin levels as well as BMD at lumbar spine, femoral neck and forearm were measured. Insulin sensitivity was assessed using Quantitative Insulin Sensitivity Check Index (QUICKI). The same parameters were measured 2 years (interquartile range 2·8 years) after surgery (PTX) in a subgroup of patients (n = 51). RESULTS: In univariate analysis, a positive relationship between insulin levels and BMD (R = 0·17, P < 0·03) or T-score (R = 0·20, P < 0·005) was found at femoral neck level. Consequently, a negative relationship between QUICKI and femoral BMD (R = -0·20, P < 0·01) or T-score (R = -0·21, P < 0·004) was found. In multivariate analysis, when femoral BMD was the dependent variable, age (beta = -0·35, P < 0·000004), BMI (beta = 0·39, P < 0·00001), PTH (beta = -0·18, P < 0·05) and QUICKI (R = -0·15, P < 0·05) had an independent effect (R(2) = 0·29). Insulin levels and QUICKI did not change after PTX. No relationship was found between QUICKI or insulin levels at the time of diagnosis and change in BMD at any site at follow-up. CONCLUSIONS: Our data show a weak relationship between insulin levels and/or insulin sensitivity and BMD in PHPT. However, the insulin state does not influence change in bone density after PTX in PHPT.

Silent renal stones in primary hyperparathyroidism: prevalence and clinical features.

OBJECTIVE: (1) To evaluate the prevalence of silent nephrolithiasis in patients with primary hyperparathyroidism (PHPT) compared with controls, and (2) To characterize clinically PHPT patients with silent renal stones. METHODS: We reviewed clinical data for 141 patients with PHPT and without symptoms or history of nephrolithiasis in whom renal ultrasonography was performed at diagnosis. A total of 141 sex- and age- matched subjects with abdomen ultrasonography obtained for reasons different from urinary symptoms served as controls. RESULTS: Silent nephrolithiasis was more prevalent in PHPT patients than in controls (11.35% vs. 2.13%; P = .003). Among patients with PHPT, those with silent renal stones showed higher serum calcium and parathyroid hormone levels and met surgical criteria, regardless of nephrolithiasis, more frequently than those without renal stones. CONCLUSION: The prevalence of silent nephrolithiasis is increased in patients with PHPT as compared with controls. Moreover, it seems likely that silent renal stone disease could identify a subset of PHPT patients with more severe disease. Accordingly, we suggest ultrasonographic screening of nephrolithiasis in all PHPT patients. Further studies are needed to better characterize this clinical entity.

Obesity in Prediabetic Patients: Management of Metabolic Complications and Strategies for Prevention of Overt Diabetes.

Obesity and prediabetes affect a substantial part of the general population, but are largely underdiagnosed, underestimated, and undertreated. Prediabetes differs from diabetes only in the degree of hyperglycaemia consequent to the progressive decline in residual beta-cell function. Both prediabetes and diabetes occur as a consequence of insulin resistance that starts several years before the clinical onset of overt diabetes. Macrovascular complications in patients with diabetes are mainly caused by insulin resistance. This is why in prediabetes, the overall cardiovascular risk is, by all means, similar to that in patients with diabetes. It is important, therefore, to identify prediabetes and treat patients not only to prevent or delay the onset of diabetes, but to reduce the cardiovascular risk associated with prediabetes. This review provides an overview of the pathophysiology of prediabetes in patients with obesity and the progression toward overt diabetes. We have reviewed nutritional and pharmacological approaches to the management of obesity and reduced glucose tolerance, and the treatment of the major comorbidities in these patients, including hypertension, dyslipidaemia, and Metabolic dysfunction-associated Steatotic Liver Disease (MASLD), has also been reviewed. In patients with obesity and prediabetes, the nutritional approach is similar to that adopted for patients with obesity and diabetes; treatments of dyslipidaemia and hypertension also have the same targets compared to patients with diabetes. MASLD is a critical issue in these patients; in the prediabetic state, MASLD rarely progresses into fibrosis. This highlights the importance of the early recognition of this pathological condition before patients become diabetic when the risk of fibrosis is much higher. It is necessary to raise awareness of the clinical relevance of this pathological condition in order to prompt early intervention before complications occur. The single most important therapeutic goal is weight loss, which must be early and persistent.

Italian National Registry of Alopecia Areata: an epidemiological study of 699 Italian patients.

BACKGROUND: Alopecia areata (AA) is an organ-specific autoimmune disease that affects the hair follicles of the scalp and the rest of the body causing hair loss. Due to the unpredictable course of AA and the different degrees of severity of hair loss, only a few well-designed clinical studies with a low number of patients are available. Also, there is no specific cure, but topical and systemic anti-inflammatory and immune system suppressant drugs are used for treatment. The need to create a global registry of AA, comparable and reproducible in all countries, has recently emerged. An Italian multicentric electronic registry is proposed as a model to facilitate and guide the recording of epidemiological and clinical data and to monitor the introduction of new therapies in patients with AA. METHODS: The aim of this study was to evaluate the epidemiological data of patients with AA by collecting detailed information on the course of the disease, associated diseases, concomitant and previous events, and the clinical response to traditional treatments. Estimate the impact on the quality of life of patients. RESULTS: The creation of the National Register of AA has proven to be a valid tool for recording, with a standardized approach, epidemiological data, the trend of AA, response to therapies and quality of life. CONCLUSIONS: AA is confirmed as a difficult hair disease to manage due to its unpredictable course and, in most cases, its chronic-relapsing course, capable of having a significant impact on the quality of life of patients.

Vitamin D status in primary hyperparathyroidism: a Southern European perspective.

BACKGROUND: Vitamin D deficiency (VDD) is common in patients with primary hyperparathyroidism (pHPT), and this could affect the clinical expression of the disease. However, few North American or North European studies have addressed this issue, showing vitamin D repletion in only about one-third of the patients. SUBJECTS AND METHODS: Vitamin D status was evaluated both in an observational study in a series of 206 consecutive patients with pHPT at diagnosis and in a case-control analysis with 113 age- and sex-matched healthy blood donors. Vitamin D status was assessed by measuring plasma 25-hydroxy-vitamin D (25OHD) levels and was defined as VDD or severe VDD if 25OHD was <20 ng/ml (<50 nm) and <10 ng/ml (<25 nm), respectively. RESULTS: No seasonal variability was observed in 25OHD levels. VDD was observed in 75 of 206 patients (36·4%). The VDD was severe in 24 of 75 patients (11·7%). There was no difference in prevalence of VDD between men and women nor between asymptomatic and 'bone and stone' symptomatic patients. 25OHD levels was negatively correlated with parathyroid hormone, ionized calcium, and bone turnover markers, and positively correlated with phosphate. 25OHD levels were also positively correlated with bone mineral density at all sites measured. In the case-control study, the overall prevalence of VDD and severe VDD was higher in patients with pHPT compared with controls (33·6% vs 10·6%, P < 0·0001, and 8·8% vs 1·8%, P = 0·0337, respectively). CONCLUSIONS: Our study shows that VDD occurs in about one-third of patients with pHPT resident in a Southern European area, a lower figure than previously reported. Moreover, VDD is related to a more severe bone disease, and its prevalence is higher in patients with pHPT than in healthy matched subjects.

Band-edge ultrafast pump-probe spectroscopy of core/shell CdSe/CdS rods: assessing electron delocalization by effective mass calculations.

CdSe/CdS dot/rods nanocrystals show interesting physical properties related to the band-alignment at the hetero-interface, which controls the band-edge electron delocalization over the rods. Here the differential transmission spectra of CdSe/CdS nanorod samples with different core sizes have been measured using excitation resonant to the core transition. The photo bleaching ratio between dot and rod transitions increases with the dot size, indicating a trend towards electron localization. This trend has been further quantified by performing effective mass calculations in which the conduction band misalignment was varied in order to reproduce the observed bleaching feature ratio. The best agreement was found for negligible conduction band misalignment for small dots of around 2.3 nm in diameter, and about -0.1 eV misalignment was estimated for the larger dots, above 3.5 nm in diameter. This shows that the band misalignment might be dependent on the geometry of the system, and we argue that this might be related to different strain developed at the hetero-interface.

Plasmon dynamics in colloidal Cu2-xSe nanocrystals.

The optical response of metallic nanostructures after intense excitation with femtosecond-laser pulses has recently attracted increasing attention: such response is dominated by ultrafast electron-phonon coupling and offers the possibility to achieve optical modulation with unprecedented terahertz bandwidth. In addition to noble metal nanoparticles, efforts have been made in recent years to synthesize heavily doped semiconductor nanocrystals so as to achieve a plasmonic behavior with spectrally tunable features. In this work, we studied the dynamics of the localized plasmon resonance exhibited by colloidal Cu(2-x)Se nanocrystals of 13 nm in diameter and with x around 0.15, upon excitation by ultrafast laser pulses via pump-probe experiments in the near-infrared, with ∼200 fs resolution time. The experimental results were interpreted according to the two-temperature model and revealed the existence of strong nonlinearities in the plasmonic absorption due to the much lower carrier density of Cu(2-x)Se compared to noble metals, which led to ultrafast control of the probe signal with modulation depth exceeding 40% in transmission.

Alopecia Areata Occurring after COVID-19 Vaccination: A Single-Center, Cross-Sectional Study.

Limited data concerning the development of autoimmune skin diseases after COVID-19 vaccination are currently available. Recently, a few reports described the development, worsening or recurrence of alopecia areata after the administration of COVID-19 vaccines. High variability in terms of disease onset following vaccination as well as the heterogeneous topical and/or systemic treatment approaches have been described. Methods: All patient-related data and images were obtained as part of clinical routine. Diagnosis of alopecia areata was established according to clinical and trichoscopic findings, along with the exclusion of common differential diagnoses. Results. Twenty-four patients, 20 females (83.3%) and four males (16.7%), with a mean age of 39.1 years (age range: 14-66 years), were examined for the occurrence of alopecia areata within 16 weeks after COVID-19 vaccination. Out of 24, 14 patients (58.3%) experienced a patchy alopecia areata, while an extensive disease occurred in 10/24 patients (41.7%): six patients with whole scalp involvement (alopecia areata totalis) and four patients with the whole body affected (alopecia areata universalis). Twelve patients reported a history of autoimmune disease (50%). Treatment with topical corticosteroid was performed in almost all patients with patchy alopecia areata, whilst it was associated with systemic drugs (corticosteroids, minoxidil, cyclosporin) in the case of generalized alopecia areata and alopecia areata universalis. Mean baseline values of Severity of Alopecia Tool (SALT) score decreased from 43.4 to 36.6 after 12 weeks of treatment, with evidence of hair regrowth in 16/21 patients. Conclusion. This study described the occurrence of alopecia areata after COVID-19 vaccination and its management that implicates the use of both topical and systemic therapies.

A Multi-professional Approach for Transition of Care at Discharge in Hyperglycemic Inpatients with COVID-19: A Single Center Study.

BACKGROUND: The discharge from the hospital of insulin-treated hyperglycemic patients is always challenging. This is even more so in patients requiring glucocorticoid treatment, such as those with COVID-19. PATIENTS AND METHODS: A retrospective monocentric study of 23 inpatients was conducted with newly diagnosed or already known diabetes mellitus (DM) who were naïve to insulin treatment, and who were hospitalized with COVID-19 in non-critical settings and then discharged. Patients were followed up for one month after discharge for the management of insulin treatment by a multi-professional team through phone consultations. RESULTS: Insulin prescriptions at discharge were 24.6 ± 14 U/day injected in 2 ± 1.5 daily shots. A mean of three phone consultations was required. One month later, the mean insulin reduction was 1.5 ± 1.3 shots and 6 ± 5 U/day. All patients reached their glycemic target without hypoglycemic events, drop-outs, or readmissions. CONCLUSION: This study demonstrates the feasibility, efficacy, and safety of a multi-professional approach through telemedicine for managing DM patients after discharge during COVID-19.

Steady-state photoinduced absorption of CdSe/CdS octapod shaped nanocrystals.

Colloidal branched nanocrystals have been attracting increasing attention due to evidence of an interesting relationship between their complex shape and charge carrier dynamics. Herein, continuous wave photoinduced absorption (CW PIA) measurements of CdSe/CdS octapod-shaped nanocrystals are reported. CW PIA spectra show strong bleaching due to the one-dimensional (1D) CdS pod states (480 nm) and the zero-dimensional (0D) CdSe core states (690 nm). The agreement with previously reported ultrafast pump-probe experiments indicates that this strong bleaching signal may be assigned to state filling. Additional bleaching features at 520 and 560 nm are characterized by a longer lifetime and are thus ascribed to defect states, localized at the pod-core interface of the octapod, showing that some of the initially photogenerated carriers get quickly trapped into these long-lived defect states. However, we remark that a relevant part of electrons remain untrapped: this opens up the opportunity to exploit octapod shaped nanocrystals in photovoltaics applications, as electron acceptor materials, considering that several efficient hole extracting materials are already available for the realization of a composite bulk heterojunction.

Suppression of biexciton auger recombination in CdSe/CdS dot/rods: role of the electronic structure in the carrier dynamics.

We studied carrier dynamics in semiconductor nanocrystals consisting of a small CdSe dot embedded in an elongated, rod-shaped CdS shell, using the ultrafast pump-probe technique. We found clear evidence of a substantial suppression of the Auger nonradiative recombination in the biexciton regime. Moreover, a simple model of the dynamics in which biexcitons show no Auger recombination, and only holes are localized in the dot, fits well the differential transmission observed at all pump densities. The long biexciton lifetime results into an observed long-living gain having a peak that is red shifted with respect to the lowest energy absorption peak. We argue that the origin of the large relative gain observed at large fillings is related to the peculiar structure of the electronic levels, and in particular, to delocalization of electrons in the rod.

Diabetes and Bone Involvement in Primary Hyperparathyroidism: Literature Review and Our Personal Experience.

Background: Primary hyperparathyroidism (PHPT) and type 2 diabetes mellitus (T2DM) are common endocrine disorders impacting on skeletal health, whose concomitant occurrence is becoming more frequent. Patients and Methods: We searched the PubMed database from the National Library of Medicine about the relationship between T2DM and its treatment and bone manifestations of PHPT. Thereafter, we retrospectively evaluated a consecutive series of 472 PHPT patients. Among them 55 were also affected by T2DM. At the diagnosis of PHPT we compared bone turnover markers and bone densitometry between 55 patients with and 417 without T2DM and in the former group according to antidiabetic treatment. Results: Few data are available about T2DM and PHPT bone involvement, studies about T2DM treatments and PHPT bone manifestations are lacking. Among patients with PHPT of our series, those with T2DM were older, had a lower prevalence of osteitis fibrosa cystica, higher lumbar and femoral T-scores than the remaining patients. No difference was disclosed among the diabetic patients according to ongoing antidiabetic treatment, even though modern treatments were under-represented. Conclusions: No clinical study specifically evaluated the impact of T2DM on bone involvement in PHPT. In our experience, diabetic patients resulted more frequently "mild asymptomatic" than non-diabetic patients and showed a lower prevalence of radiological PHPT bone manifestations. The treatment of T2DM does not seem to affect the biochemical or clinical features of PHPT in our series. Further studies are needed to fully disclose the influence of T2DM and antidiabetic treatment on bone health in patients with PHPT.

Persistence of Elevated Procalcitonin in a Patient with Coronavirus Disease 2019 Uncovered a Diagnosis of Medullary Thyroid Carcinoma.

OBJECTIVE: During the ongoing coronavirus disease 2019 pandemic, procalcitonin (PCT) levels have proven useful in assisting clinicians to diagnose bacterial superinfection. However, in the absence of signs of infection or at the resolution thereof, inappropriately and persistently high PCT levels may suggest and reveal the presence of other pathologies. We report a patient with severe acute respiratory syndrome coronavirus 2 pneumonia with initially elevated PCT levels that persisted during recovery, prompting the diagnosis of medullary thyroid carcinoma (MTC). METHODS: A 43-year-old man presented with a 2-day history of fever, sneezing, sore throat, and dry cough. His PCT was 94 ng/mL (normal value, 0.00-0.10 ng/mL), and he was positive for severe acute respiratory syndrome coronavirus 2 RNA. RESULTS: Empirical antibiotic therapy was administered for 7 days, but despite a clinical improvement, serum PCT remained high (84 ng/mL). Serum calcitonin (CTN) was 2120 pg/mL (normal, ≤12 pg/mL). Cytologic examination of thyroid nodules and CTN measurement of the aspiration needle washout confirmed MTC. The patient underwent total thyroidectomy with bilateral cervical lymph node dissection. Lowered CTN (986 pg/mL) and PCT (16 ng/mL) levels were observed 48 hours after surgery. A close follow-up was planned following the results of RET gene analysis. CONCLUSION: PCT can be a useful biochemical marker of MTC suspicion in patients with inflammatory conditions and persistently elevated PCT, even after resolution. In our case, high levels of PCT in a patient with coronavirus disease 2019 pneumonia without signs of bacterial infection led to MTC diagnosis.

[Renal function in primary hyperparathyroidism]. / Iperparatiroidismo primario e rene.

The kidney is one of the classical target organs of PTH action. Symptomatic primary hyperparathyroidism (PHPT) is nowadays less frequent but mostly occurs with renal symptoms, in particular kidney stones. Nephrocalcinosis and polyuria, the latter closely related to the severity of hypercalcemia, are uncommon. Parathyroidectomy leads to a marked and long-lasting improvement of nephrolithiasis, whereas it has a limited effect on nephrocalcinosis. Kidney failure is one of the long-term complications of PHPT and is associated with a more severe clinical expression of the disease and a higher risk of morbidity and mortality. Current guidelines on the management of asymptomatic PHPT, the most common presentation of PHPT today, recommend surgical treatment if renal function is decreased. However, in this particular clinical setting it is unclear whether PHPT is really associated with a more rapid decline of renal function or whether successful parathyroidectomy could protect renal function.

Reflectance Confocal Microscopy Applied to Folliculitis Decalvans: Preliminary Results of a Multicenter Study.

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.