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The process of quasi-isothermal dehydration of thin films of pure water and aqueous sugar solutions is investigated with a dual experimental and theoretical approach. A nanoporous paper disk with a homogeneous internal structure was used as a substrate. This experimental set-up makes it possible to gather thermodynamic data under well-defined conditions, develop a numerical model, and extract needed information about the dehydration process, in particular the water activity. It is found that the temperature evolution of the pure water film is not strictly isothermal during the drying process, possibly due to the influence of water diffusion through the cellulose web of the substrate. The role of sugar is clearly detectable and its influence on the dehydration process can be identified. At the end of the drying process, trehalose molecules slow down the diffusion of water molecules through the substrate in a more pronounced way than do the glucose molecules. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the risk factors for postoperative vasopressor requirement among patients with pheochromocytoma undergoing retroperitoneal adrenalectomy. The primary outcome was postoperative hypotension requiring vasopressor support., Design: A single-center retrospective observational study., Setting: At a university hospital., Participants: Adults who underwent unilateral adrenalectomy for pheochromocytoma between October 2015 and February 2020., Interventions: None., Measurements and Main Results: Overall, 201 patients were included. Postoperative vasopressor requirements were observed in 39 (19.4%) patients, and were associated with baseline coronary artery disease (CAD) (odds ratio [OR] 6.21, 95% CI) 2.48-15.52; p = 0.0001), maximal systolic blood pressure (maxSBP) >195 mmHg (OR 3.71, 95% CI 1.53-8.95; p = 0.0035), and >5.1-fold increase in the upper limit of normal values for baseline adrenergic activity (OR 4.9, 95% CI 1.93-12.55; p = 0.0008). The area under the receiver operating characteristic curve of the predictive model was 0.804 (95% CI 0.742-0.856)., Conclusion: A MaxSBP >195 mmHg, baseline adrenergic activity >5.1-fold increase in the upper limit of normal values, and baseline CAD could predict postresection requirements for vasoactive support. Prospective multicenter international studies are required to develop and validate universally accepted predictive models for postoperative complications in patients after adrenalectomy for pheochromocytoma., Competing Interests: Conflict of Interest None., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The aim of the present study was to test a hypothesis that baseline systemic vascular resistance index (SVRI) assessed by method of transpulmonary thermodilution predicts perioperative requirement for vasoactive drugs. The primary outcomes were: (1) peak vasoactive-inotropic score (VIS) and (2) peak dose of hypotensive drugs at any stage of surgery. The main exposure variable was baseline SVRI. Hemodynamics were retrospectively assessed by transpulmonary thermodilution in 50 adults who had undergone posterior retroperitoneal surgery for pheochromocytoma. Univariate linear regression analysis showed predictive value of SVRI on VIS [regression coefficient, 95% CI; 0.024 (0.005, 0.4), p=0.015]. Other significant factors were the history of peak diastolic pressure, baseline MAP, baseline betablocker therapy, and history of coronary artery disease (CAD). After adjustment of SVRI for the history of CAD, its prognostic value became non-significant [0.018 (0.008, 0.03), p=0.063 and 29.6 (19, 40.2), p=0.007 for SVRI and history of CAD, respectively]. Requirements of vasodilators were predicted by baseline adrenergic activity [0.37 (0.005, 0.74), p=0.047]. In conclusion, baseline SVRI is associated with perioperative requirement of vasopressor drugs, but history of CAD is a stronger prognostic factor for vasopressor support. Perioperative requirement in vasodilators is associated with baseline adrenergic activity., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

In this paper, solid-state amorphization induced by mechanical milling is shown to be a useful tool to explore the polymorphism of drugs and their mechanism of devitrification. We show in particular how the recrystallization of amorphous chlorhexidine dihydrochloride obtained by milling reveals a complex polymorphism that involves several polymorphic forms. Two new crystalline forms are identified, one of them appearing as a highly disordered precursor state which however clearly differs from the amorphous one. Several interpretations are here proposed to describe the puzzling nature of this phase. In addition, the possibility to amorphize chlorhexidine dihydrochloride by milling allowed to determine the main physical characters of the amorphous state which cannot be obtained through the usual thermal quench of the liquid because of a strong chemical degradation occurring on melting., (Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

The present molecular epidemiology study was carried out to evaluate the genotoxic effects of occupational exposure to antineoplastic drugs (ANP). The study was conducted in 52 hospital workers involved in the preparation, handling or administration of ANP in a hospital in Perugia (central Italy) and in 52 non-exposed control subjects matched for age, gender and smoking habits to the exposed subjects. Both comet assay and the micronucleus test were used to evaluate genome damage in peripheral blood lymphocytes in study subjects. The extent of primary DNA damage, as evaluated by the comet assay, was significantly increased in exposed personnel with respect to matched controls. On the other hand, no significant differences in micronuclei frequency was observed between the two groups. Multivariate linear regression analysis showed an association between years of occupational exposure over 10 years and higher extent of primary DNA damage in the exposed group. The results of this study confirm that handling ANP without appropriate precautions carries a genotoxic risk for exposed healthcare workers. These results address the need for regular biological effect monitoring of staff occupationally-exposed to ANP.