Studies on the effects of mixed light-thermal ageing on parchment by vibrational spectroscopy and micro hot table method

Abstract The damaging effects of mixed light-thermal ageing on parchment were studied by exposing mock-ups to artificial light (162 W/m2 irradiance) at controlled temperature and relative humidity (52 °C, 30% RH) for up to 748 h, with testing being made during this time incrementally. The physical–chemical changes (deterioration) resulting from these conditions were analysed by applying FTIR-ATR and Raman spectroscopy, colorimetric measurements and MHT. The deterioration found includes the formation of collagen-destabilised intermediate states which then progressively convert to disorganised structures, e.g. pregelatinised collagen and gelatin. The process is characterized by molecular changes of collagen associated with its photo-oxidation. These are shown by changes in the position and intensity of the main FTIR absorption bands of collagen, namely those of Amide I, Amide II, and Amide III, as well as by the occurrence and the increase of a shoulder at 1740 cm−1. The shrinking activity of the collagen fibres in the parchment mock-ups was measured by the micro-hot-table (MHT) method, which revealed the presence of multiple collagen populations with distinct thermal stabilities and confirmed the deterioration pattern suggested by the molecular changes

From acute hypercalcaemia to post-parathyroidectomy hungry bone syndrome in a patient with primary hyperparathyroidism-associated brown tumours

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Thermal characterization of new, artificially and naturally aged leather and parchment samples

Handwritten books, codices and letters stored or displayed in historic buildings are vulnerable to changes in the outdoor environment due to the limited climate control. Understanding the degradation mechanisms and changes in the structure of leather and parchment could help to find a proper way to protect these pieces from the aging and the environmental effects. In order to identify the aging mechanisms different analytical methods, among them thermoanalytical methods were used. In this work natural aging mechanisms were modeled by acid and alkaline pretreatments. Structural changes of the samples during the aging were explored using thermoanalytical methods, in order to understand the response of parchment and leather to the environmental effects

Parathyroids: Pandemic update

Parathyroid glands-related issues (also involving calcium-phosphorus metabolism) amid pandemic are represented by: complicated recovery after COVID-19 infection in cases with severe vitamin D (VD) deficiency or uncorrected hypocalcemia (hCa); the cases with primary hyperparathyroidism-related hypercalcemia who are postponed for parathyroid adenoma removal might be complicated with arrhythmia if the patient becomes COVID-19 positive; lockdown restrictions limited the physical activity, a situation which might aggravate sarcopenia and bone mineral density loss; subjects with renal hyperparathyroidism who do not have controlled values of serum calcium are at higher risk of severe COVID-19 infection due to a wide area of chronic renal failure-associated complications, including Ca, VD and PTH disturbances. This is an update concerning parathyroid glands in relationship to two-year pandemic experience. The mini-review of literature is based on PubMed navigation using a combination of key words like “parathyroid glands”, “parathyroid”, “parathormone”, “vitamin D”, “calcium” and “COVID-19” or “coronavirus” or “pandemic”. During the first months of COVID-19 pandemic there was a massive reduction of parathyroidectomies volume which was elective for severe forms associating life threatening values of serum calcium. The number of parathyroidectomies increased during the second year of pandemic Hypocalcemia remains a poor prognostic factor in severe COVID-19 infections while underling mechanisms are complex and might not be exclusively related to vitamin D deficiency which is a topic still on trends. Direct hypoparathyroidism is a new entity amid coronavirus-induced puzzle. E-health is mandatory to follow calcium correcting medication and associated life style intervention in cases with anomalies of calcium/PTH/VD levels

Thermal characterization of new, artificially aged and historical leather and parchment

The aging mechanism of leather and parchment was studied by thermoanalytical methods to understand the effect of the environment on the historical manuscripts and the heritage of libraries and archives. Alkaline and acidic treatments followed by thermal dehydration were applied to achieve chemical changes in the structure of new leather and parchment similar to the slow natural aging of historical samples. Chemical and structural changes during both natural and artificial aging processes were characterized by thermoanalytical techniques. The thermal stability and the evolution profile of the decomposition products under slow heating were studied by thermogravimetry/mass spectrometry (TG/MS). The distribution of the decomposition products of these collagen-based materials under fast pyrolysis was characterized by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). It was found that the maximal rate of the thermal decomposition (DTGmax) significantly decreases by aging in case of both leather and parchment samples indicating the degree of deterioration. Py-GC/MS has been found to be a suitable technique to sensitively monitor the degradation of the polyphenolic components of the vegetable tannins under natural or artificial aging. It was established that the tannin content of leather is more significantly affected by natural aging and alkaline treatment than the main structure of the polypeptide chains. Principal component analysis (PCA) has been used to find statistical correlations between the experimental data for leather samples. The results of the PCA confirmed that the alkaline treatment and the natural aging processes similarly modify the tannin content of the vegetable tanned leather

Adrenal surgery amid COVID-19 pandemic

COVID-19 pandemic affected every aspect of medical life, including the field of adrenal glands (AG). Our purpose is to overview the literature concerning AG domain, especially adrenal surgery amid COVID-19 pandemic. The approach of adrenal tumors (AT) is reflected by two aspects: what happens to a patient known with an adrenal mass if COVID-19 infection is positive and the other is related to restrictions amid pandemic daily practice that involve AT surgery. Patients with AT underling active hormonal over-production are at higher risk of COVID-19 infection or at increased risk of developing a more severe form of coronavirus infection, for instance, via diabetes mellitus, high blood pressure, and obesity. During the first year of pandemic, especially if considering the periods with severe restrictions and lockdown, there was a massive reduction of adrenalectomies, when compare to the same months of the previous year. Several systems of deciding the timing of intervention were used; they is still an insufficient statistical validation of these scores until now. The reduction of surgery volume was less expressive during the second year of pandemic. The rate of peri-operatory infections is relatively low, but it depends on center. Post-operative adrenal insufficiency exposes the patient to a higher risk of infections, including coronavirus infection. Peri-operative management can be handle via telemedicine in most of cases

Gamma Knife radiosurgery: effect on corticotropin-secreting pituitary adenoma

Introduction: Cushing's disease (CD) is a complex endocrine disorder characterized by an increased risk of recurrence and persistence of hypercortisolism after initial transsphenoidal adenomectomy, a situation requiring alternative therapeutic measures. Case presentation: A 21-year-old female patient was admitted for weight gain with centripetal fat distribution, transient headache, hair thinning and psycho-emotional lability. Clinical examination revealed round facies, acne, purple-red striae, hirsutism with a Ferriman-Gallwey score of 20. The hormonal profile revealed high serum cortisol (of 283.1 ng/mL, normal:70-225 ng/mL) and high ACTH (Adrenocorticotropic Hormone) levels (of 260.6 pg/mL, normal: 7.2-63.3 pg/mL). The pituitary MRI (Magnetic Resonance Imaging) examination found a 4.3/4.4/6.2mm left paramedian microadenoma. The persistence of hypercortisolism after adenomectomy required GKRS (Gamma Knife radiosurgery). Four months after radiosurgery, complete remission of the disease was achieved and it was maintained at the last evaluation. At present, the patient is 20 weeks pregnant. Conclusions: Gamma Knife radiosurgery offers a high control rate of pituitary adenomas and a reasonable rate of remission of residual hypercortisolism after neurosurgical treatment. After surgery or GKRS, periodic monitoring is necessary for patients with CD due to the risk of pituitary insufficiency or relapse

DIFFERENT INDICATIONS, ONE PROCEDURE: THYROIDECTOMY (AS SIMPLE AS THAT)

Introduction. Thyroidectomy is currently a rather simple procedure with various indications, regardless total or subtotal/near total, based on conventional approach or modern like robotic (trans-axillary and axillobreast robotic). We aim to introduce a few scenarios in daily endocrine practice based on a pictorial essay. This is a cases series. Case 1 is a 59-year old female with recent subclinical thyrotoxicosis with an extremely large multinodular goitre who was confirmed benign by the pathological report was provided after. Case 2 is a 70-year old female who self detected through palpation a large left thyroid macronodule with suspected ultrasound features. However, she still delays thyroidectomy. Case 3 is a 51-year old female also with compressive symptoms due multinodular goitre and a dominant left lobe nodule who was referred to surgery. Case 4 is a 59-year female treated with thiamazole for 12 years presents a large multinodular goitre which was referred to surgery. Conclusion. Different scenarios are ending with the idea of thyroidectomy from compressive local symptoms, to curative option for a potential malignancy etc

Follow-up of second adrenal tumor after remission of Cushing syndrome

Bilateral adrenal tumors (BAT) represent a vast domain of endocrinology and connected medical and surgical fields. Our purpose is to introduce several key points in relationship with long time management on a 56-year old female case who is currently admitted for reassessment of a left adrenal tumor with potential autonomous cortisol secretion. She is also known with pituitary incidentaloma since 2014, cerebral meningioma which was partially removed in 2015, uncontrolled diabetes mellitus under metformin and insulin therapy since 2017, and high blood pressure since 2021. Her medical history includes right adrenalectomy for Cushing syndrome in 2014. At that moment, she was first admitted for BAT, a tumor of 2 centimeters (cm) on the left gland according to computed tomography, respective of 3.5 cm maximum diameter on the right adrenal. The hormonal panel confirmed adrenal Cushing syndrome. After 6 months of non-interventional follow-up, the right tumor increased to 4 cm, also associating small areas of necrosis, thus a decision of unilateral laparoscopic adrenalectomy was done with good clinical post-operatory outcome. She did not develop adrenal insufficiency at any point in time, moreover, a low-normal ACTH (Adrenocorticotrop Hormone) with intermittent elevation of morning plasma cortisol levels after Dexamethasone suppression test showed a possible autonomous cortisol secretion of the left adrenal tumor during a 7-year follow-up. In 2014, the female patient received the confirmation of an adrenocortical adenoma which was consistent with cortisol over-secretion. Particular gene contributions are attributed to protein kinase A (PKA) defects (or B) that usually induce bilateral adrenocortical hyperplasia; however, they are not routinely tested in daily endocrine practice, neither had we performed it. Interestingly, the patient was detected with a cerebral meningioma after years of intermittent, mild headache. The diagnostic was established during initial endocrine evaluations. The headache was not associated with uncontrolled high blood pressure, as first expected due to excessive cortisol amount. Recently, it was identified that mutations of ARMC5 (armadillo repeat containing 5) gene are responsible for macronodular adrenal hyperplasia, but also meningioma. They may be also responsible for severe diabetes mellitus as seen here. The key points of following a patient with bilateral adrenal tumors include the timing of uni/bilateral adrenalectomy, the multidisciplinary management of associated complications, as well as the need of understanding the genetic rational behind it

Side-chain Poly[2]pseudorotaxanes containing β-cyclodextrin for more sustainable tanning process

Sustainability of leather lies in how the hide, a sustainable, naturally renewable, raw material, is processed. Tanning chemistry has been a limiting factor for leather sustainability. In this study, a host-guest synthesis strategy was selected to modify one of the most widely used tanning polymer, MIDA DD, and obtain a new hybrid tanning system containing fl-cyclodextrin, and leather drastically less impactful on the earth and people. Poly[2] pseudorotaxane Side-Chain Complexes (PSCCs) have been obtained by threading fl-cyclodextrin units onto the side-chains of the commercial MIDA DD. The formation of PSCCs in aqueous solution was investigated by using 1D NMR, ATR-FTIR and TGA experiments. The ability of PSCCs to stabilize the collagen matrix was tested at laboratory and industrial pilot scale by micro-DSC, ATR-FTIR and solid-state NMR techniques. The physical and mechanical performance of the obtained crust leather was determined by standard tests used in tanning industry. Side-chain poly[2]pseudorotaxanes showed better tanning performances than the fossil-based MIDA DD, the most effective supramolecular tannins being obtained by mixing fl-CD and MIDA DD in ratios close to 1/1 (w/w). The new tanning mixtures allow for significantly reducing both the amount of fossil-based MIDA-DD polymer in the current tanning processes (by 45%) and the free bisphenol content in leather crust (by more than 80%) due to the presence of bio-based fl-CD in the composition of the new supramolecular tanning agents. The findings disclosed here pave the way for the CDs' employment in improving the sustainability of tanning processes