The amorphous-to-crystalline transformation of nitrendipine was investigated using Raman spectroscopy and X-ray powder diffraction (XRPD). The nucleation and growth rate of crystalline nitrendipine in a medium containing poly (vinyl alcohol) (PVA) and polyethylene glycol (PEG 200) were quantitatively determined using image analysis based on polarized light microscopy. The findings from the image analysis revealed that the transformation process occurred through the dissolution of amorphous drug precipitate followed by the nucleation and growth of the crystalline phase with the amorphous precipitate acting as a reservoir for maintaining the supersaturation. The rates of nucleation and crystal growth of nitrendipine decreased with an increase in PEG 200 concentration in organic phase from 0% to 75% (v/v). Increasing the PVA concentration in water phase from 0.1% to 1.0% (w/w) also decreased the rates of nucleation and crystal growth, however, an increase in PVA concentration from 1.0% to 2.0% (w/w) did not result in a further decrease in the rates of nucleation and crystal growth. An increase in drug concentrations in the organic phase from 10 mg/ml to 30 mg/ml led to faster nucleation rates. However, a further increase in drug concentration to 100mg/ml decelerated the growth of nitrendipine crystals. Combining image analysis of polarized light micrographs together with Raman spectroscopy and XRPD provided an in-depth insight into solid state transformations in amorphous nitrendipine suspensions.
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http://dx.doi.org/10.1016/j.ejps.2012.03.008 | DOI Listing |
J Hand Surg Am
January 2025
Hand and Upper Extremity Division of Plastic and Reconstructive Surgery, University of California Davis, Sacramento, CA.
Purpose: Current technologies to define the zone of acute peripheral nerve injury intraoperatively are limited by surgical experience, time, cumbersome electrodiagnostic equipment, and interpreter reliability. In this pilot study, we evaluated a real-time, label-free optical technique for intraoperative nerve injury imaging. We hypothesize that fluorescence lifetime imaging (FLIm) will detect a difference between the time-resolved fluorescence signatures for acute crush injuries versus uninjured segments of peripheral nerves in sheep.
View Article and Find Full Text PDFAm J Sports Med
January 2025
Department of Orthopaedic Surgery, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, South Korea.
Background: Studies are still limited on the isolated effect of retear after arthroscopic rotator cuff repair (ARCR) on functional outcomes after the midterm period.
Purpose: To assess the effect of retear at midterm follow-up after ARCR and to identify factors associated with the need for revision surgery.
Study Design: Cohort study; Level of evidence, 3.
Med Sci Monit
January 2025
Department of Oral Implantology, The Affiliated Stomatology Hospital, Jiangxi Medical College, Nanchang University, Jiangxi Province Key Laboratory of Oral Biomedicine, Jiangxi Province Clinical Research Center for Oral Disease, Nanchang, Jiangxi, China.
BACKGROUND This study included 32 patients with single missing teeth and alveolar bone defects and aimed to compare outcomes from guided bone regeneration with a gelatin/polylactic acid (GT/PLA) barrier membrane and a Guidor® bioresorbable matrix barrier dental membrane. MATERIAL AND METHODS A total of 32 participants were recruited in the clinical study, with single missing teeth and alveolar bone defects, requiring guided bone regeneration (32 missing teeth in total). They were randomly divided into the GT/PLA membrane group (experimental) and Guidor® membrane group (control) by the envelope method (n=16).
View Article and Find Full Text PDFCommun Biol
January 2025
Center for Research on Genomics and Global Health, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
Single cell studies have transformed our understanding of cellular heterogeneity in disease but the need for fresh starting material can be an obstacle, especially in the context of international multicenter studies and archived tissue. We developed a protocol to obtain high-quality cells and nuclei from dissected human skeletal muscle archived in the preservative Allprotect® Tissue Reagent. After fluorescent imaging microscopy confirmed intact nuclei, we performed four protocol variations that compared sequencing metrics between cells and nuclei enriched by either filtering or flow cytometry sorting.
View Article and Find Full Text PDFJ Cancer Res Clin Oncol
January 2025
Sarcoma Unit, Department of Surgery, University Medical Center and Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
Purpose: The management of soft tissue sarcoma (STS) at reference centers with specialized multidisciplinary tumor boards (MTB) improves patient survival. The German Cancer Society (DKG) certifies sarcoma centers in German-speaking countries, promoting high standards of care. This study investigated the variability in treatment recommendations for localized STS across different German-speaking tertiary sarcoma centers.
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