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Fluoride in drinking water has beneficial or harmful health effects depending on its concentration. This highlights the need for new low-cost and portable sensors capable of in situ monitoring of F- ions. Unfortunately, achieving high levels of water compatibility and fluoride specificity remains a challenge. Here, four new urea-based discrete sensors are prepared and characterized. The sensors containing anthracenyl- (5) and 9H-fluorenyl- (7) signaling units exhibit intense luminescent emissions in dimethyl sulfoxide, the former being particularly sensitive and selective to fluoride. In water, 5 displays a superior sensitivity (871 M-1) and a detection limit (8 µm) below international guidelines, albeit with cross-sensitivity to H2PO4â¾. To enhance the performance, 5 and 7 are embedded into a fluoride-imprinted polymeric matrix to give solid-state sensors (5P and 7P, respectively). 5P shows good sensitivity (360 M-1) and specificity in water. Besides, it has a low detection limit (35 µm) and a response linear range (118-6300 µm) encompassing the limit established by the Environmental Protection Agency (211 µm). Furthermore, 5P also displays good reusability and adequate recovery values in real-sample testing (102 ± 2%), constituting the first example of a low-cost anion-imprinted polymeric probe tailored for the selective sensing of fluoride in aqueous samples.
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The review explores the 2022 update to the World Health Organization (WHO) classification of pituitary adenomas, now referred to as pituitary neuroendocrine tumors (PitNETs), and his possible impact on the clinical management of PitNET patients. The review highlights the differences and the evolution from the 2017 to 2022 version, with the current classification considering the lineage of the tumor cells, cell type, hormones produced, and other auxiliary characteristics for a comprehensive histological classification. The revision in terminology reflects a broader perspective on neuroendocrine neoplasia. The new approach based on transcription factors, hormone expression and other biomarkers has allowed a major revision of the nomenclature and a more accurate classification of pituitary adenomas. Furthermore, in some cases this approach is also assuming a prognostic value, useful in clinical practice. However, despite this elaborate classification and stratification, the review points out the lack of a robust grading or staging system and suggests the need for further research and validation of diagnostic methods. Despite these limitations, the revised classification presents a significant step towards understanding and managing PitNETs patients.
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BACKGROUND: Hypophysitis is a rare inflammatory disorder of the pituitary gland. Symptoms and signs of hypophysitis can be various, and its recognition may be challenging. Arginine vasopressin deficiency (AVP-D) due to exposure to a variety of drugs and toxic substances is rare, but some cases have been reported. Only 2 cases of AVP-D following toxic exposure to toluene, an aromatic hydrocarbon, have been reported in the literature. To our knowledge, our case represents the first description of an infundibulo neurohypophysitis (INH), manifested with AVP-D, secondary to inhalation of toluene. CASE REPORT: A 59-year-old man with an unremarkable medical history was referred to our department for headache, polyuria, and polydipsia after the inhalation of spray film containing toluene. The blood tests revealed a hyperosmolar plasma hypernatremia with normal kidney function. A desmopressin test was performed, with an improvement in water balances, blood electrolytes, and diuresis contraction. A pituitary MRI detected the absence of a normal hyperintense signal of the neuro-pituitary in the T1-weighted images. In consideration of the clinical signs and radiological imaging suggestive of INH, a therapy with desmopressin and corticosteroids was instituted, with gradual improvement of polyuria and resolution of the radiological features of INH. CONCLUSION: The exceptional finding of INH, manifested with AVP-D, following toluene inhalation could represent a new secondary cause of hypophysitis. The possibility that drugs or toxic substances never reported before could induce INH should not be excluded since the study on hypophysitis is relatively recent but emerging, predictably destined to increase exponentially in the coming years.
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BACKGROUND: Acromegaly is associated with skeletal fragility and increased prevalence of vertebral fractures (VF). Two isoforms of GH receptor (GHR) have been described, which differ in the presence or absence of a transcript of exon 3 of the GHR gene. Both isoforms produce a functional receptor, but the exon 3-deleted isoforms (d3-GHR) have greater sensitivity to endogenous and recombinant GH than the full-length isoform (fl-GHR). OBJECTIVE: We conducted a longitudinal, retrospective, observational, single-center study to investigate the role of GHR polymorphism as a prognostic factor of incidental VF (I-VF) in firstgeneration somatostatin analogs (fg-SSAs)-resistant acromegalic patients and treated with Pegvisomant or Pasireotide LAR. METHODS: Seventy-two patients with active acromegaly were included: 28 patients carried the d3-GHR isoform, and 44 patients carried the fl-GHR isoform. Forty-six patients were treated with Pegvisomant in combination with fg-SSAs, and 26 were treated with Pasireotide LAR. At the last follow-up, 58 patients achieved biochemical control of acromegaly. Eighteen patients carried prevalent VF (P-VFs), while 14 patients experienced the occurrence of I-VFs. RESULTS: From the group treated with Pegvisomant in combination with fg-SSAs, 32 patients carried the fl-GHR isoform, and 14 carried the d3-GHR isoform. From the group treated with Pasireotide LAR, 12 patients had the fl-GHR isoform, and 14 patients carried the d3-GHR isoform. I-VF occurred more frequently in patients with the fl-GHR isoform compared to d3-GHR (p =0.04); otherwise, I-VF occurred more frequently in patients with the d3-GHR isoform than fl-GHR (p =0.01). CONCLUSION: The GHR polymorphisms could improve the therapeutic approach in acromegaly, tailored to the individual patient, in the context of personalized medicine.
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BACKGROUND: The pseudo-Cushing's encompass several disorders that can occur in high-stress situations and that show biochemical features like those of Cushing's syndrome. We present a case with difficult differential diagnosis for overlapping laboratory findings. CASE REPORT: A 74-year-old man was admitted to our hospital for worsening dyspnoea for a month, 15 kilograms of weight loss in the previous months, asthenia, hypotonia, and muscle hypotrophy. Moreover, due to the onset of acute hypoxic-hypercapnic respiratory failure, the patient was treated with non-invasive ventilation and then admitted to the intensive care unit, for pneumonia and respiratory failure due to Meticillin-sensitive Staphylococcus aureus and Klebsiella Aerogenes. Antibiotic therapy was started. During the treatment in the ICU, the patient underwent endotracheal intubation for the worsening of respiratory function, and inotropic drug therapy was introduced for the development of septic shock. Hormones were tested, showing an ACTH-dependent hypercortisolism. The results of Nugent, Liddle, and the dexamethasone- suppressed CRH stimulation tests suggested a not-neoplastic ACTH-dependent hypercortisolism. The pituitary contrasted magnetic resonance image showed gland hypertrophy, and the abdominal computed tomography ruled out adrenal lesions. Unfortunately, the patient developed a multi-organ failure and died. The autopsy finding confirmed the absence of pituitary and other neuroendocrine tumors and showed bilateral adrenal hypotrophy. CONCLUSION: Our clinical case described a patient with pseudo-Cushing's syndrome during sepsis and pre-agonist phase, with a difficult differential diagnosis, in which the combination of the low-dose dexamethasone suppression test and the CRH test allowed a conclusive and correct diagnostic orientation.
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INTRODUCTION: Hypophysitis is an inflammatory disorder of the pituitary gland. It can manifest variously, with endocrinological and neuro-ophthalmologic symptoms and signs, due to the compression of sellar and parasellar structures. CASE REPRESENTATION: Although hypophysitis is rare, this pituitary disease can occur during pregnancy or in the postpartum period. In this report, we describe the case of a woman with partial hypopituitarism secondary to autoimmune hypophysitis who, five years after the diagnosis and the immunosuppressive treatment, had an uneventful pregnancy and successfully delivered a healthy infant at term. CONCLUSION: We reported the clinical history of the patient and the evolution of the disease and also reviewed the management and treatment of autoimmune hypophysitis during pregnancy.
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Pasireotide-LAR is recommended as a second-line treatment for patients with acromegaly. Although the effects of pasireotide-LAR have been well characterized in clinical studies, real-practice evidence is scant, especially in the long term and within the individualization of therapy in patients with comorbidities. To provide additional insight on the individualized approach to acromegaly management, six clinical cases of complex acromegaly treated with pasireotide-LAR for more than 5 years were reported. Pasireotide-LAR allowed the normalization of insulin-like growth factor 1 (IGF1) values in all patients and reduced tumour residue volume where present. A good safety profile and long-term tolerability were also reported.
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INTRODUCTION: Skeletal fragility is a clinically relevant and not-reversible complication of acromegaly, involving around 30-40% of patients since the disease diagnosis. Few studies have investigated the effects on skeletal health of medical therapies for acromegaly. In this retrospective longitudinal monocentre study, we investigated the outcome of skeletal fragility in patients treated with Pasireotide Lar in combination with Pegvisomant (Pasi-Lar + Peg-V), also comparing those observed in patients treated with conventional therapies. RESULTS: We included 6 patients treated with Pasi-Lar + Peg-V, 5 patients treated with Peg-V in monotherapy (m-Peg-V), 16 patients treated with Peg-V plus first-generation somatostatin receptor ligands (fg-SRLs + Peg-V), 9 patients treated with Pasi-Lar. None of the patients treated with Pasi-Lar + Peg-V experienced worsening of spine and femoral bone mineral density (BMD) and incident vertebral fractures (i-VFs). Eight patients experienced i-VFs. The frequency of i-VFs was significantly lower in patients treated with the Pasi-Lar + Peg-V (0/8; 0%), as compared to those observed in m-Peg-V treated patients (4/8; 50%, p = 0.02). The frequency of i-VFs was slightly but not significantly higher in Pasi-Lar treated patients (1/8; 12.5% p = 0.6) and in fg-SRLs + Peg-V treated patients (3/8; 37.5% p = 0.364), concerning those treated with Pasi-Lar + Peg-V (0/8; 0%). I-VFs occurred more frequently in patients with higher GH levels at acromegaly diagnosis (p < 0.001), and in patients who experienced a BMD worsening (p = 0.005). CONCLUSION: Our preliminary data suggested that in conventional and multi-drug resistant acromegaly, the combination therapy Pasi-Lar + Peg-V may prevent the worsening of BMD and the occurrence of i-VFs. Prospective and translational studies should further validate these results and ascertain underlying physiopathology mechanisms.
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Acromegalia , Densidade Óssea , Hormônio do Crescimento Humano , Somatostatina , Humanos , Acromegalia/tratamento farmacológico , Densidade Óssea/efeitos dos fármacos , Pessoa de Meia-Idade , Feminino , Masculino , Estudos Retrospectivos , Adulto , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Hormônio do Crescimento Humano/análogos & derivados , Projetos Piloto , Idoso , Estudos LongitudinaisRESUMO
Filters made of graphene oxide (GO) are promising for purification of water and selective sieving of specific ions; while some results indicate the ionic radius as the discriminating factor in the sieving efficiency, the exact mechanism of sieving is still under debate. Furthermore, most of the reported GO filters are planar coatings with a simple geometry and an area much smaller than commercial water filters. Here, we show selective transport of different ions across GO coatings deposited on standard hollow fiber filters with an area >10 times larger than typical filters reported. Thanks to the fabrication procedure, we obtained a uniform coating on such complex geometry with no cracks or holes. Monovalent ions like Na+ and K+ can be transported through these filters by applying a low electric voltage, while divalent ions are blocked. By combining transport and adsorption measurements with molecular dynamics simulations and spectroscopic characterization, we unravel the ion sieving mechanism and demonstrate that it is mainly due to the interactions of the ions with the carboxylate groups present on the GO surface at neutral pH.
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Several genetic investigations were conducted to identify germline and somatic mutations in somatotropinomas, a subtype of pituitary tumors. To our knowledge, we report the first acromegaly patient carrying a RET pathogenic variant: c.2410G>A (rs79658334), p.Val804Met. Alongside the fact that the patient's father and daughter carried the same variant, we investigated the clinical significance of this variant in the context of somatotropinomas and other endocrine tumors, reviewing the RET mutations' oncogenic mechanisms. The aim was to search for new targets to precisely manage and treat acromegaly. Our case describes a new phenotype associated with the RET pathogenic variant, represented by aggressive acromegaly, and suggests consideration for RET mutation screening if NGS for well-established PitNET-associated gene mutations renders negative.
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Acromegalia , Proteínas Proto-Oncogênicas c-ret , Humanos , Acromegalia/genética , Mutação em Linhagem Germinativa , Neoplasia Endócrina Múltipla Tipo 2a/genética , Mutação , Fenótipo , Proteínas Proto-Oncogênicas c-ret/genética , Neoplasias da Glândula Tireoide/genéticaRESUMO
BACKGROUND: We aim to assess the role of a multidisciplinary approach in pituitary adenomas (PitNETs) classification, evaluate criteria concordance, and compare intraoperative assessments with post-operative MRIs for tumor remnants. METHODS: Clinical, radiological, histological, and intra- and post-operative data of the treated PitNETs were extracted from prospectively created records. PitNETs were graded according to Trouillas, and the evaluation of the tumor remnants was recorded. RESULTS: Of 362 PitNETs, 306 underwent surgery, with Trouillas grading assigned to 296. Eight-nine radiologically non-invasive PitNETs progressed to grades 1b (27), 2a (42), or 2b (20) due to proliferative or surgical invasiveness criteria. Twenty-six radiologically invasive tumors were graded 2b due to proliferative criteria. Surgical resection details and post-surgical MRI findings revealed that residual tumors were more common in grades 2a and 2b. During surgery, small tumor remnants were documented in 14 patients which were not visible on post-surgical MRI. Post-surgical MRIs identified remnants in 19 PitNETs not seen during surgery, located in lateral recesses of the sella (4), retrosellar (2), or suprasellar regions (7), along the medial wall of the cavernous sinus (6). CONCLUSIONS: The Pituitary Board allows for the correct grading of PitNETs to be obtained and an accurate identification of high-risk patients who should undergo closer surveillance due to tumor remnants.
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Purpose: The aim of this study was to examine the probability of achieving acromegaly disease control according to several patient-, disease- and treatment-related factors longitudinally. Methods: We analyzed data from ACROSTUDY, an open-label, noninterventional, post-marketing safety surveillance study conducted in 15 countries. A total of 1546 patients with acromegaly and treated with pegvisomant, with available information on baseline IGF-1 level, were included. Factors influencing IGF-1 control were assessed up to 10 years of follow-up by mixed-effects logistic regression models, taking into account changing values of covariates at baseline and at yearly visits. Twenty-eight anthropometric, clinical and treatment-related covariates were examined through univariate and multivariate analyses. We tested whether the probability of non-control was different than 0.50 (50%) by computing effect sizes (ES) and the corresponding 95% CI. Results: Univariate analysis showed that age <40 years, normal or overweight, baseline IGF-1 <300 µg/L or ranged between 300 and 500 µg/L, and all pegvisomant dose <20 mg/day were associated with a lower probability of acromegaly uncontrol. Consistently, in multivariate analyses, the probability of uncontrolled acromegaly was influenced by baseline IGF-1 value: patients with IGF-1 <300 µg/L had the lowest risk of un-controlled acromegaly (ES = 0.29, 95% CI: 0.23-0.36). The probability of acromegaly uncontrol was also lower for values 300-500 µg/L (ES = 0.37, 95% CI: 0.32-0.43), while it was higher for baseline IGF-1 values ≥700 µg/L (ES = 0.58, 95% CI: 0.53-0.64). Conclusion: Baseline IGF-l levels were a good predictor factor for long-term acromegaly control. On the contrary, our data did not support a role of age, sex, BMI and pegvisomant dose as predictors of long-term control of acromegaly. Significance statement: Among factors that could influence and predict the efficacy of pegvisomant therapy in controlling acromegaly, a central role of baseline IGF-1 values on the probability of achieving a biochemical control of acromegaly during the treatment with pegvisomant was identified, in a real-life setting.
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BACKGROUND: Pancreatic metastases from medullary thyroid carcinoma (MTC) are exceptional. Imaging and treatment based on somatostatin receptors may play a role, though the evidence is unconvincing. CASE PRESENTATION: We have, herein, documented a unique case of metastatic MTC, where pancreatic metastasis was identified by 68Ga-PET/CT, with the disease showing very slow progression during treatment with lanreotide autogel. A 51-year-old woman underwent total thyroidectomy for goiter in 2000, with a postoperative diagnosis of MTC. Due to persistent disease, somatostatin analogues (SSA) treatment commenced in 2005, following a positive acute octreotide test. In 2012, a pathology-confirmed pancreatic metastasis was diagnosed via 68Gallium-positron emission tomography (68Ga-PET/CT). The disease progressed very slowly over 17 years of SSA treatment. CONCLUSION: This uncommon case of pancreatic metastasis from MTC indicates that nuclear medicine techniques might offer valuable additional information. Extended treatment with lanreotide autogel appears to correlate with very slow disease progression in selected patients.
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A new atomically precise, single-ion catalyst (MWCNT-LPd) for ORR (oxygen reduction reaction), consisting of a Pd(II) complex of a tetraazacycloalkane anchored on multiwalled carbon nanotubes, has been prepared through a supramolecular approach ensuring a uniform distribution of catalytic centres on the support surface. A tetraazacycloalkane was chosen to saturate the four coordination sites of the typical square planar coordination geometry of Pd(II) with the aim of ascertaining whether the metal ion must have free coordination sites to function effectively in the ORR or whether, as predicted by quantum mechanical calculations, the catalytic effect can be originated from an interaction of O2 in the fifth coordinative position. The results clearly demonstrated that tetracoordination of Pd(II) does not influence its catalytic capacity in the ORR. Electrodes based on this catalyst show ORR performance very close to that of commercial Pt electrodes, despite the low Pd(II) content (1.72% by weight) in the catalyst. The onset potential (Eon) value and the half-wave potential (E1/2) of the catalyst are, respectively, only 53 mV and 24 mV less positive than those observed for the Pt electrode and direct conversion of O2 to H2O reaches 85.0%, compared to 89% of the Pt electrode. Furthermore, a preliminary galvanostatic test (simulating a working fuel cell at a fixed potential) showed that the catalyst maintains its efficiency continuing to produce water throughout the process (the average number of electrons exchanged over time per O2 molecule remains close to 4).
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CONTEXT: The prompt control of acromegaly is a primary treatment aim for reducing related disease morbidity and mortality. First-generation somatostatin receptor ligands (fg-SRLs) are the cornerstone of medical therapies. A non-negligible number of patients do not respond to this treatment. Several predictors of fg-SRL response were identified, but a comprehensive prognostic model is lacking. OBJECTIVE: We aimed to design a prognostic model based on clinical and biochemical parameters, and pathological features, including data on immune tumor microenvironment. METHODS: A retrospective, monocenter, cohort study was performed on 67 medically naïve patients with acromegaly. Fifteen clinical, pathological, and radiological features were collected and analyzed as independent risk factors of fg-SRLs response, using univariable and multivariable logistic regression analyses. A stepwise selection method was applied to identify the final regression model. A nomogram was then obtained. RESULTS: Thirty-seven patients were fg-SRLs responders. An increased risk to poor response to fg-SRLs were observed in somatotropinomas with absent/cytoplasmatic SSTR2 expression (OR 5.493 95% CI 1.19-25.16, P = .028), with low CD68+/CD8+ ratio (OR 1.162, 95% CI 1.01-1.33, P = .032). Radical surgical resection was associated with a low risk of poor fg-SRLs response (OR 0.106, 95% CI 0.025-0.447 P = .002). The nomogram obtained from the stepwise regression model was based on the CD68+/CD8+ ratio, SSTR2 score, and the persistence of postsurgery residual tumor and was able to predict the response to fg-SRLs with good accuracy (area under the curve 0.85). CONCLUSION: Although our predictive model should be validated in prospective studies, our data suggest that this nomogram may represent an easy to use tool for predicting the fg-SRL outcome early.
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BACKGROUND: In adamantinomatous craniopharyngiomas, tumor topographical categories, cystic component volume, and magnetic resonance signal intensity may impact prognosis. OBJECTIVE: To identify magnetic resonance imaging (MRI) variables associated with pituitary-hypothalamic axis dysfunction and predictive of outcome in children with cystic adamantinomatous craniopharyngiomas. MATERIALS AND METHODS: We evaluated 40 preoperative MRIs of adamantinomatous craniopharyngiomas to classify tumor topography, volume, and signal intensity of the cystic components and peritumoral edema. Volumes and normalized signal intensity minimum values were extracted from coronal T2-weighted images (nT2min). Radiological variables were compared to pituitary-hypothalamic axis dysfunction-related clinical data and surgical outcomes. RESULTS: Adamantinomatous craniopharyngiomas were categorized into five topographic classes (12 patients, sellar-suprasellar; seven patients, pseudo-intraventricular; six patients, strict intraventricular; 14 patients, secondary intraventricular; one patient, not strict intraventricular). All cases exhibited a predominant (30 patients, 80%) or total (10 patients, 20%) cystic tumor component and displayed low nT2min percentage values compared to cerebrospinal fluid (42.3% [interquartile range 28.4-54.6%]). Significant associations between tumor topographic classes and pituitary dysfunction (P<0.001), and between peritumoral edema and hypothalamic dysfunction (P<0.001) were found. Considering extent of surgical removal and tumor relapse, volume of the cystic tumor component displayed a positive correlation (P=0.002; r=0.48; P=0.02; r=0.36), while nT2min intensity values exhibited a negative correlation (P=0.01; r= - 0.40; P=0.028; r= - 0.34). CONCLUSION: Severe hypothalamic-pituitary axis dysfunction is associated with tumors along the pituitary stalk and peritumoral edema. Tumor invasion of the third ventricle, tight adherence to the hypothalamus, larger volumes, and lower nT2min intensity of the tumor cystic component are independent predictors of extent of adamantinomatous craniopharyngioma excision and recurrence.
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Craniofaringioma , Neoplasias Hipofisárias , Criança , Humanos , Craniofaringioma/diagnóstico por imagem , Craniofaringioma/cirurgia , Craniofaringioma/patologia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Imageamento por Ressonância Magnética/métodos , Hipotálamo/diagnóstico por imagem , Hipotálamo/patologia , EdemaRESUMO
Recently, advances in molecular biology and bioinformatics have allowed a more thorough understanding of tumorigenesis in aggressive PitNETs (pituitary neuroendocrine tumors) through the identification of specific essential genes, crucial molecular pathways, regulators, and effects of the tumoral microenvironment. Target therapies have been developed to cure oncology patients refractory to traditional treatments, introducing the concept of precision medicine. Preliminary data on PitNETs are derived from preclinical studies conducted on cell cultures, animal models, and a few case reports or small case series. This study comprehensively reviews the principal pathways involved in aggressive PitNETs, describing the potential target therapies. A search was conducted on Pubmed, Scopus, and Web of Science for English papers published between 1 January 2004, and 15 June 2023. 254 were selected, and the topics related to aggressive PitNETs were recorded and discussed in detail: epigenetic aspects, membrane proteins and receptors, metalloprotease, molecular pathways, PPRK, and the immune microenvironment. A comprehensive comprehension of the molecular mechanisms linked to PitNETs' aggressiveness and invasiveness is crucial. Despite promising preliminary findings, additional research and clinical trials are necessary to confirm the indications and effectiveness of target therapies for PitNETs.
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Tumores Neuroendócrinos , Neoplasias Hipofisárias , Animais , Humanos , Neoplasias Hipofisárias/patologia , Hipófise/metabolismo , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/terapia , Tumores Neuroendócrinos/metabolismo , Agressão , Microambiente Tumoral/genéticaRESUMO
It is urgent yet challenging to develop new environmentally friendly and cost-effective sources of energy. Molecular solar thermal (MOST) systems for energy capture and storage are a promising option. With this in mind, we have prepared a new water-soluble (pH > 6) norbornadiene derivative (HNBD1) whose MOST properties are reported here. HNBD1 shows a better matching to the solar spectrum compared to unmodified norbornadiene, with an onset absorbance of λonset = 364 nm. The corresponding quadricyclane photoisomer (HQC1) is quantitatively generated through the light irradiation of HNBD1. In an alkaline aqueous solution, the MOST system consists of the NBD1-/QC1- pair of deprotonated species. QC1- is very stable toward thermal back-conversion to NBD1-; it is absolutely stable at 298 K for three months and shows a marked resistance to temperature increase (half-life t½ = 587 h at 371 K). Yet, it rapidly (t½ = 11 min) releases the stored energy in the presence of the Co(II) porphyrin catalyst Co-TPPC (ΔHstorage = 65(2) kJâmol-1). Under the explored conditions, Co-TPPC maintains its catalytic activity for at least 200 turnovers. These results are very promising for the creation of MOST systems that work in water, a very interesting solvent for environmental sustainability, and offer a strong incentive to continue research towards this goal.
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Since the late '80s, CERN has pioneered the development of niobium thin film radio-frequency (RF) cavities deposited on copper substrates for several particle accelerator applications. However, niobium thin film cavities historically feature a progressive performance degradation as the accelerating field increases. In this study, we describe a temperature mapping system based on contact thermometry, specially designed to obtain temperature maps of niobium-coated copper cavities and, consequently, study the mechanisms responsible for performance degradation. The first temperature maps on a niobium/copper 1.3 GHz cavity are reported along with its RF performance. In addition to some hotspots displayed in the temperature maps, we surprisingly observed a temperature decrease in a limited portion of the cavity cell as the accelerating field increased. This may shed new light on understanding the heat dissipation of niobium thin film cavities in liquid helium-I, which might be exploited to improve the RF cavity performance.
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Hypophysitis, a rare inflammatory disorder of the pituitary gland, has seen an uptick in reported cases in recent years. Our objective is to summarize the most recent research on the etiopathogenesis, molecular mechanisms, and genetics of both primary and secondary hypophysitis. Primary autoimmune hypophysitis (PAH): During the acute phase of the disease, the pituitary gland in enlarged due to the infiltration of T and B lymphocytes. The chronic phase is characterized by progressive and irreversible pituitary atrophy. APA may play a role in the management, diagnosis, and prognosis of PAH. Specific autoantibodies such as anti-GH, anti-PIT-1, and anti-T-PIT have been found in patients with hypophysitis and hypopituitarism. A recent study suggested that a mechanism of escaping clonal deletion and mounting an immune response against self antigens can explain the unusual nature of the immune response observed in PAH patients. A cytokine array shows the presence of gamma-interferon and interleukin-17. Patients carrying mutations in the PIT1 or PROP1 genes may present PAH. Individuals carrying the HLA DQ8 haplotype are four times more likely to develop PAH. Immune checkpoint inhibitors induce hypophysitis (IIHs): IIHs is an increasingly frequent toxicity of in patients on treatment with inhibitors targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death-1 (PD-1). ICIs inhibit the CTLA-4 pathway, leading to overactivation of T lymphocytes. The binding of PD-1/PD-L1 suppresses the activity of T cells, promotes the conversion of T-helpers into T-regulatory cells, and activates pro-survival signaling pathways in cancer cells. Cytokines play a crucial role in IIHs. B-cell infiltration has been observed in IIHs, suggesting that antibody-mediated pituitary injury may contribute. Genetic polymorphisms of CTLA-4 and PD-1 genes can increase the risk of IIHs. HLA alleles may also be involved in the onset of IIHs; this HLA association presents a possible alternative mechanistic hypothesis. IIHs may also be linked to a paraneoplastic syndrome triggered by ectopic expression of pituitary specific antigens. SARS-CoV-2-related hypophysitis: Recently, the literature has reported occurrences of hypophysitis associated with the SARS-CoV-2 virus; long COVID-19 may also present as infundibulo-neuro-hypophysitis. The virus enters the central nervous system because of its distinct interaction with angiotensin-converting enzyme receptors via spike proteins binding the capillary endothelium, and it directly damages the pituitary cells. The effect of SARS-CoV-2 can occur indirectly through inflammation and the release of cytokines. The exact mechanism remains ambiguous. The available data on endocrine complications associated with the SARS-CoV-2 vaccine are scant. Nonetheless, isolated cases of hypophysitis have been documented. Treatment of hypophysitis: Glucocorticoids are the cornerstone in managing primary hypophysitis, given their targeted action on inflammation. A better understanding of the etiopathogenesis and molecular mechanism of hypophysitis can lead to more effective and personalized treatment strategies.