0
selected
-
1.
Processability evaluation of multiparticulate units prepared by selective laser sintering using the SeDeM Expert System approach.
Vasiljević, I, Turković, E, Piller, M, Mirković, M, Zimmer, A, Aleksić, I, Ibrić, S, Parojčić, J
International journal of pharmaceutics. 2022;:122337
Abstract
3D printing in dosage forms fabrication is in the focus of researchers, however, the attempts in multiparticulate units (MPUs) preparation are scarce. The aim of this study was to fabricate different size MPUs by selective laser sintering (SLS), using different polymers, and investigate their processability based on the SeDeM Expert System approach. MPUs (1- or 2-mm size) were prepared with model drug (ibuprofen or caffeine), polymer (poly(ethylene)oxide (PEO), ethyl cellulose (EC) or methacrylic acid-ethyl acrylate copolymer (MA-EA)) and printing aid. Comprehensive sample characterization was performed and experimentally obtained parameters were mathematically transformed and evaluated using the SeDeM Expert System framework. The obtained samples exhibited irregular shape, despite the spherical printing object design. Polymer incorporated notably affected MPUs properties. The obtained samples exhibited low bulk density, good flowability-, as well as stability-related parameters, which indicated their suitability for filling into capsules or sachets. Low density values implied that compressibility enhancing excipients may be required for MPUs incorporation in tablets. Samples containing EC and MA-EA were found suitable for compression, due to high compacts tensile strength. The obtained results indicate that SeDeM Expert System may extended from powder compressibility evaluation tool to framework facilitating powders/multiparticulate units processing.
-
2.
Evolution of the nutritional status of COVID-19 critically-ill patients: A prospective observational study from ICU admission to three months after ICU discharge.
Rives-Lange, C, Zimmer, A, Merazka, A, Carette, C, Martins-Bexinga, A, Hauw-Berlemont, C, Guerot, E, Jannot, AS, Diehl, JL, Czernichow, S, et al
Clinical nutrition (Edinburgh, Scotland). 2022;(12):3026-3031
-
-
Free full text
-
Abstract
BACKGROUND & AIMS Malnutrition following intensive care unit (ICU) stay is frequent and could be especially prominent in critically ill Coronavirus Disease 2019 (COVID-19) patients as they present prolonged inflammatory state and long length stay. We aimed to determine the prevalence of malnutrition in critically ill COVID-19 patients both at the acute and recovery phases of infection. METHODS We conducted a prospective observational study including critically ill COVID-19 patients requiring invasive mechanical ventilation discharged alive from a medical ICU of a university hospital. We collected demographic, anthropometric and ICU stay data (SAPS2, recourse to organ support and daily energy intake). Nutritional status and nutritional support were collected at one month after ICU discharge (M1) by phone interview and at 3 months after ICU discharge (M3) during a specialized and dedicated consultation conducted by a dietitian. Malnutrition diagnosis was based on weight loss and body mass index (BMI) criteria following the Global Leadership Initiative on Malnutrition. Primary outcome was the prevalence of malnutrition at M3 and secondary outcomes were the evolution of nutritional status from ICU admission to M3 and factors associated with malnutrition at M3. RESULTS From march 13th to may 15th, 2020, 38 patients were discharged alive from the ICU, median [IQR] age 66 [59-72] years, BMI 27.8 [25.5-30.7] kg/m2 and SAPS2 47 [35-55]. Thirty-three (86%) patients were followed up to M3. Prevalence of malnutrition increased during the ICU stay, from 18% at ICU admission to 79% at ICU discharge and then decreased to 71% at M1 and 53% at M3. Severe malnutrition prevailed at ICU discharge with a prevalence of 55% decreasing 32% at M3. At M3, the only factors associated with malnutrition in univariate analysis were the length of invasive mechanical ventilation and length of ICU stay (28 [18-44] vs. 13 [11-24] days, P = 0.011 and 32 [22-48] vs. 17 [11-21] days, P = 0.006, respectively), while no ICU preadmission and admission factors, nor energy and protein intakes distinguished the two groups. Only 35% of undernourished patients at M3 had benefited from a nutritional support. CONCLUSION Malnutrition is frequent, protracted and probably underrecognized among critically ill Covid-19 patients requiring invasive mechanical ventilation with more than half patients still being undernourished three months after ICU discharge. A particular attention should be paid to the nutritional status of these patients not only during their ICU stay but also following ICU discharge.
-
3.
New insights into structure-function relationships of oxalyl CoA decarboxylase from Escherichia coli.
Werther, T, Zimmer, A, Wille, G, Golbik, R, Weiss, MS, König, S
The FEBS journal. 2010;(12):2628-40
-
-
Free full text
-
Abstract
The gene yfdU from Escherichia coli encodes a putative oxalyl coenzyme A decarboxylase, a thiamine diphosphate-dependent enzyme that is potentially involved in the degradation of oxalate. The enzyme has been purified to homogeneity. The kinetic constants for conversion of the substrate oxalyl coenzyme A by the enzyme in the absence and presence of the inhibitor coenzyme A, as well as in the absence and presence of the activator adenosine 5'-diphosphate, were determined using a novel continuous optical assay. The effects of these ligands on the solution and crystal structure of the enzyme were studied using small-angle X-ray scattering and X-ray crystal diffraction. Analyses of the obtained crystal structures of the enzyme in complex with the cofactor thiamine diphosphate, the activator adenosine 5'-diphosphate and the inhibitor acetyl coenzyme A, as well as the corresponding solution scattering patterns, allow comparison of the oligomer structures of the enzyme complexes under various experimental conditions, and provide insights into the architecture of substrate and effector binding sites.
-
4.
Comparison of bioresorbable and titanium plates in cervical spinal fusion: early radiologic and clinical results.
Nabhan, A, Ishak, B, Steimer, O, Zimmer, A, Pitzen, T, Steudel, WI, Pape, D
Journal of spinal disorders & techniques. 2009;(3):155-61
Abstract
STUDY DESIGN This is a prospective, randomized, and controlled study, approved by the local ethical committee of Saarland (Germany), no. 209/06. OBJECTIVE The aim of this study was to compare clinical results, segmental motility, magnetic resonance imaging (MRI) compatibility, and change of the bone density of a cervical spine segment that was treated with either bioresorbable or titanium plates in single level. SUMMARY AND BACKGROUND DATA Anterior cervical discectomy and fusion including plate fixation is an accepted technique for treatment of symptomatic degenerative disc disease. Titanium plates have been used but cause imaging artifacts. Radiolucent bioresorbable plates and screws were developed to reduce the imaging artifacts associated with titanium. METHODS Forty patients with single level cervical radiculopathy were randomized to anterior discectomy and fusion with bioresorbable plate (19 patients, study group) or titanium plate (18 patients, control group). Follow-up used a visual analog scale (VAS) with regard to brachial pain and Neck Disability Index (NDI) for neck pain. Radiostereometry was performed immediately postoperative and after 6 weeks, 3, and 6 months. MRI of the cervical spine was obtained immediately postoperatively at 3 and 6 months to assess hematoma, infection, and swelling. Computed tomography of the operated cervical spine segment was performed to assess bone density, expressed in Hounsfield units. RESULTS Three-dimensional analysis of segmental motion (medio-lateral, cranio-caudal and anterior-posterior) did not reveal any statistical difference between both groups at any time postoperatively (P>0.05). Fusion rate and speed evaluated on Radiostereometric analysis and computed tomography of cervical spine segment were similar in both groups. MRI of cervical spine did not show any pathology, especially hematoma and infection. The VAS and NDI did not differ between both groups after 6 months (P>0.05). CONCLUSIONS Anterior plate fixation by using a bioresorbable plate has the same fusion progress and stability as titanium. During the study, no complications like soft tissue swelling and infection occurred.
-
5.
Creatine monohydrate and conjugated linoleic acid improve strength and body composition following resistance exercise in older adults.
Tarnopolsky, M, Zimmer, A, Paikin, J, Safdar, A, Aboud, A, Pearce, E, Roy, B, Doherty, T
PloS one. 2007;(10):e991
Abstract
Aging is associated with lower muscle mass and an increase in body fat. We examined whether creatine monohydrate (CrM) and conjugated linoleic acid (CLA) could enhance strength gains and improve body composition (i.e., increase fat-free mass (FFM); decrease body fat) following resistance exercise training in older adults (>65 y). Men (N = 19) and women (N = 20) completed six months of resistance exercise training with CrM (5g/d)+CLA (6g/d) or placebo with randomized, double blind, allocation. Outcomes included: strength and muscular endurance, functional tasks, body composition (DEXA scan), blood tests (lipids, liver function, CK, glucose, systemic inflammation markers (IL-6, C-reactive protein)), urinary markers of compliance (creatine/creatinine), oxidative stress (8-OH-2dG, 8-isoP) and bone resorption (Nu-telopeptides). Exercise training improved all measurements of functional capacity (P<0.05) and strength (P<0.001), with greater improvement for the CrM+CLA group in most measurements of muscular endurance, isokinetic knee extension strength, FFM, and lower fat mass (P<0.05). Plasma creatinine (P<0.05), but not creatinine clearance, increased for CrM+CLA, with no changes in serum CK activity or liver function tests. Together, this data confirms that supervised resistance exercise training is safe and effective for increasing strength in older adults and that a combination of CrM and CLA can enhance some of the beneficial effects of training over a six-month period. Trial Registration. ClinicalTrials.gov NCT00473902.