Renal hyperparathyroidism is a disease entity that is complex and poorly understood. Although there are guidelines regarding how to manage this patient group, evidence is scarce. Therefore, this ...survey-based study aims to map the physicians' attitude in terms of preference for management of renal hyperparathyroidism and the influence of patient and respondent factors.
A survey was sent to Dutch societies of nephrology, endocrinology, and surgeons with interest in endocrine surgery. The survey consisted of eight case vignettes of renal hyperparathyroidism patients who were on hemodialysis and suitable for kidney transplantation, and varied in one of three patient variables import for decision making: age (40 vs. 65 years), parathyroid hormone (40 vs. 90 pmol/L), and serum calcium level (2.25 vs. 2.8 mmol/L). For each case, respondents could choose between maintaining conservative treatment (active vitamin D metabolites), calcimimetics, or subtotal parathyroidectomy as their treatment of choice. Categorical multilevel logistic models were used to investigate the association of patient and respondent variables with treatment preference. The influence of patient variables was determined independently of each other and by means of logistic regression the probabilities of treatment choice were calculated.
In total, 115 surveys were included in the analysis. In 6 out of 8 cases, less than two-thirds of respondents agreed on the most favoured treatment. Among patient characteristics, the main disincentive for respondents not to choose conservative therapy was an elevated serum calcium level (subtotal parathyroidectomy vs conservative OR 93.1, 95%-CI: 48.39-179.07 and calcimimetics vs conservative OR 31.2 95%-CI: 18.58-52.30). Additionally, the most significant treatment differences were found between medical specialties and the experience of the respondents, expressed as the amount of cases the physician was involved in during the past year.
Elevated serum calcium levels were widely recognized and the prime reason for respondents to abandon conservative treatment. However, considerable disagreement in treatment preferences remained throughout the cases, demonstrating the current literature available being inconclusive in guiding physicians. Therefore, a high-quality trial comparing subtotal parathyroidectomy to medical treatment is needed to determine optimal treatment.
Systemic immune cell dynamics during coronavirus disease 2019 (COVID-19) are extensively documented, but these are less well studied in the (upper) respiratory tract, where severe acute respiratory ...syndrome coronavirus 2 (SARS-CoV-2) replicates
. Here, we characterized nasal and systemic immune cells in individuals with COVID-19 who were hospitalized or convalescent and compared the immune cells to those seen in healthy donors. We observed increased nasal granulocytes, monocytes, CD11c
natural killer (NK) cells and CD4
T effector cells during acute COVID-19. The mucosal proinflammatory populations positively associated with peripheral blood human leukocyte antigen (HLA)-DR
monocytes, CD38
PD1
CD4
T effector (T
) cells and plasmablasts. However, there was no general lymphopenia in nasal mucosa, unlike in peripheral blood. Moreover, nasal neutrophils negatively associated with oxygen saturation levels in blood. Following convalescence, nasal immune cells mostly normalized, except for CD127
granulocytes and CD38
CD8
tissue-resident memory T cells (T
). SARS-CoV-2-specific CD8
T cells persisted at least 2 months after viral clearance in the nasal mucosa, indicating that COVID-19 has both transient and long-term effects on upper respiratory tract immune responses.
: To date, there is no satisfactory treatment for patients with calcium and vitamin D supplementation refractive hypoparathyroidism. Parathyroid allotransplantation by design is a one-time cure ...through its restoration of the parathyroid function and, therefore, could be the solution. A systematic literature review is conducted in the present paper, with the aim of outlining the possibilities of parathyroid allotransplantation and to calculate its efficacy. Additionally, various transplantation characteristics are linked to success.
This review is carried out according to the PRISMA statement and checklist. Relevant articles were searched for in medical databases with the most recent literature search performed on 9 December 2021.
In total, 24 articles involving 22 unique patient cohorts were identified with 203 transplantations performed on 148 patients. Numerous types of (exploratory) interventions were carried out with virtually no protocols that were alike: there was the use of (non-) cryopreserved parathyroid tissue combined with direct transplantation or pretreatment using in vitro techniques, such as culturing cells and macro-/microencapsulation. The variability increased further when considering immunosuppression, graft histology, and donor-recipient compatibility, but this was found to be reported in its entirety by exception. As a result of the large heterogeneity among studies, we constructed our own criterium for transplantation success. With only the studies eligible for our assessment, the pooled success rate for parathyroid allotransplantation emerged to be 46% (13/28 transplantations) with a median follow-up duration of 12 months (Q1-Q3: 8-24 months).
Manifold possibilities have been explored around parathyroid allotransplantation but are presented as a double-edged sword due to high clinical diverseness, low expertise in carrying out the procedure, and unsatisfactory study quality. Transplantations carried out with permanent immunosuppression seem to be the most promising, but, in its current state, little could be said about the treatment efficacy with a high quality of evidence. Of foremost importance in pursuing the answer whether parathyroid allotransplantation is a suitable treatment for hypoparathyroidism, a standardized definition of transplantation success must be established with a high-quality trial.
Cobalt-based alloys such as Stellite 3 and Stellite 6 are widely used to protect stainless steel surfaces in primary circuit nuclear reactor applications where high resistance to wear and corrosion ...are required. In this study, self-mated sliding wear of Stellite 3 and Stellite 6 consolidated by hot isostatic pressing were compared. Tests were performed with a pin-on-disc apparatus enclosed in a water-submerged autoclave environment and wear was measured from room temperature up to 250 °C (a representative pressurized water reactor environment). Both alloys exhibit a microstructure of micron-sized carbides embedded in a cobalt-rich matrix. Stellite 3 (higher tungsten and carbon content) contains M7C3 and an eta (η) -carbide whereas Stellite 6 contains only M7C3. Furthermore, the former has a significantly higher carbide volume fraction and hardness than the latter. Both alloys show a significant increase in the wear rate as the temperature is increased but Stellite 3 has a higher wear resistance over the entire range; at 250 °C the wear rate of Stellite 6 is more than five times that of Stellite 3. There is only a minimal formation of a transfer layer on the sliding surfaces but electron backscatter diffraction on cross-sections through the wear scar revealed that wear causes partial transformation of the cobalt matrix from fcc to hcp in both alloys over the entire temperature range. It is proposed that the acceleration of wear with increasing temperature in the range studied is associated with a tribocorrosion mechanism and that the higher carbide fraction in Stellite 3 resulted in its reduced wear rate compared to Stellite 6.
•Sliding wear tests were conducted at 20–250 °C in lithiated deionised water.•Stellite 3 exhibited much higher wear resistance in comparison to Stellite 6.•Wear resistance was increased through higher carbide content and hardness.•Both alloys underwent fcc-hcp transformation in the cobalt matrix at 20–250 °C.•Tribocorrosion is proposed to cause steep increase of wear at above 150–200 °C.
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