In this study, the potential of perfusion calorimetry in the characterization of solvates forming isomorphic desolvates was investigated. Perfusion calorimetry was used to expose different hydrates forming isomorphic desolvates (emodepside hydrates II-IV, erythromycin A dihydrate and spirapril hydrochloride monohydrate) to stepwise increasing relative vapour pressures (RVP) of water and methanol, respectively, while measuring thermal activity. Furthermore, the suitability of perfusion calorimetry to distinguish the transformation of a desolvate into an isomorphic solvate from the adsorption of solvent molecules to crystal surfaces as well as from solvate formation that is accompanied by structural rearrangement was investigated. Changes in the samples were confirmed using FT-Raman and FT-IR spectroscopy. Perfusion calorimetry indicates the transformation of a desolvate into an isomorphic solvate by a substantial exothermic, peak-shaped heat flow curve at low RVP which reflects the rapid incorporation of solvent molecules by the desolvate to fill the structural voids in the lattice. In contrast, adsorption of solvent molecules to crystal surfaces is associated with distinctly smaller heat changes whereas solvate formation accompanied by structural changes is characterized by an elongated heat flow. Hence, perfusion calorimetry is a valuable tool in the characterization of solvates forming isomorphic desolvates which represents a new field of application for the method.
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http://dx.doi.org/10.1016/j.ejps.2011.06.008 | DOI Listing |
Res Pract Thromb Haemost
May 2024
Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
Background: Salvianolic acid B (SAB) is a major component of root (Danshen), widely used in East/Southeast Asia for centuries to treat cardiovascular diseases. Danshen depside salt, 85% of which is made up of SAB, is approved in China to treat chronic angina. Although clinical observations suggest that Danshen extracts inhibited arterial and venous thrombosis, the exact mechanism has not been adequately elucidated.
View Article and Find Full Text PDFJ Neurochem
May 2024
Department of Experimental Medical Science, Faculty of Medicine, Lund University, Lund, Sweden.
Hormone-sensitive lipase (HSL) is active throughout the brain and its genetic ablation impacts brain function. Its activity in the brain was proposed to regulate bioactive lipid availability, namely eicosanoids that are inflammatory mediators and regulate cerebral blood flow (CBF). We aimed at testing whether HSL deletion increases susceptibility to neuroinflammation and impaired brain perfusion upon diet-induced obesity.
View Article and Find Full Text PDFAm J Emerg Med
April 2024
The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States of America; Department of Emergency Medicine, Zucker School of Medicine at Hofstra/Northwell, New York, NY, United States of America; Department of Emergency Medicine, North Shore University Hospital, Manhasset, NY, United States of America.
Objective: Oxygen consumption (VO), carbon dioxide generation (VCO), and respiratory quotient (RQ), which is the ratio of VO to VCO, are critical indicators of human metabolism. To seek a link between the patient's metabolism and pathophysiology of critical illness, we investigated the correlation of these values with mortality in critical care patients.
Methods: This was a prospective, observational study conducted at a suburban, quaternary care teaching hospital.
J Nat Med
January 2024
Collage of Pharmacy, Chongqing Medical University, Chongqing, 400016, China.
The impact of hypertension on tissue and organ damage is mediated through its influence on the structure and function of blood vessels. This study aimed to examine the potential of celastrol, a bioactive compound derived from Tripterygium wilfordii Hook F, in mitigating hypertension-induced energy metabolism disorder and enhancing blood perfusion and vasodilation. In order to investigate this phenomenon, we conducted in vivo experiments on renovascular hypertensive rats, employing indirect calorimetry to measure energy metabolism and laser speckle contrast imaging to evaluate hemodynamics.
View Article and Find Full Text PDFBMC Pulm Med
October 2023
The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA.
Objective: Using a system, which accuracy is equivalent to the gold standard Douglas Bag (DB) technique for measuring oxygen consumption (VO), carbon dioxide generation (VCO), and respiratory quotient (RQ), we aimed to continuously measure these metabolic indicators and compare the values between post-cardiothoracic surgery and critical care patients.
Methods: This was a prospective, observational study conducted at a suburban, quaternary care teaching hospital. Age 18 years or older patients who underwent mechanical ventilation were enrolled.
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