Encapsulation and immobilization of papain in electrospun nanofibrous membranes of PVA cross-linked with glutaraldehyde vapor.

In this paper, papain enzyme (E.C. 3.4.22.2, 1.6 U/mg) was successfully immobilized in poly(vinyl alcohol) (PVA) nanofibers prepared by electrospinning. The morphology of the electrospun nanofibers was characterized by scanning electron microscopy (SEM) and the diameter distribution was in the range of 80 to 170 nm. The presence of the enzyme within the PVA nanofibers was confirmed by infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDXS) analyses. The maximum catalytic activity was reached when the enzyme loading was 13%. The immobilization of papain in the nanofiber membrane was achieved by chemical crosslinking with a glutaraldehyde vapor treatment (GAvt). The catalytic activity of the immobilized papain was 88% with respect to the free enzyme. The crosslinking time by GAvt to immobilize the enzyme onto the nanofiber mat was 24h, and the enzyme retained its catalytic activity after six cycles. The crosslinked samples maintained 40% of their initial activity after being stored for 14 days. PVA electrospun nanofibers are excellent matrices for the immobilization of enzymes due to their high surface area and their nanoporous structure.

Desorption of Furfural from Bimetallic Pt-Fe Oxides/Alumina Catalysts.

In this work, the desorption of furfural, which is a competitive intermediate during the production of biofuel and valuable aromatic compounds, was studied using pure alumina, as well as alumina impregnated with iron and platinum oxides both individually and in combination, using thermogravimetric analysis (TGA). The bimetallic sample exhibited the lowest desorption percentage for furfural. High-resolution transmission electron microscopy (HRTEM) imaging revealed the intimate connection between the iron and platinum oxide species on the alumina support. The mechanism of furfural desorption from the Pt-Fe/Al2O3 0.5%-0.5% sample was determined using physisorbed furfural instead of chemisorbed furfural; this mechanism involved the oxidation of the C=O group on furfural by the catalyst. The oxide nanoparticles on γ-Al2O3 support helped to stabilize the furfural molecule on the surface.

Usefulness of intra-abdominal pressure in a predominantly medical intensive care unit.

BACKGROUND: The deleterious effects of elevated intra-abdominal pressure (IAP) have been known for more than a century. The proposed objectives were to measure changes in IAP and analyze increase-related factors and complications and whether high IAP and its persistence are related to complications and mortality in a predominantly medical intensive care unit. METHODS: Over a 1-year period, we conducted a prospective cohort study in which IAP was measured using the bladder method. Hospitalization time, demographic variables, diagnosis on admission, APACHE II score, and clinical complications were recorded. RESULTS: A total of 130 patients were studied. Overall mean IAP was 12.3 mm Hg (standard deviation [SD], 3.79; 95% confidence interval [CI], 11.7-13), and on the first day, 12.68 mm Hg (SD, 5.32; 95% CI, 11.8-13.6); maximum IAP was 16.4 mm Hg (SD, 4.6; 95% CI, 15.6-17.2). A positive correlation was found between IAP, APACHE (Acute Physiology And Chronic Health Evaluation) II, and age. Higher IAP values were independently associated with higher age, prolonged activated partial thromboplastin time, need for dialysis, and intolerance to enteral feeding. The value showing the best sensitivity and specificity in predicting mortality was persistence of IAP 20 mm Hg or greater for 4 days or more. The number of days with IAP 20 mm Hg or greater was a factor associated with a higher risk of death (odds ratio, 2.3). Patients who died showed a tendency to increased IAP. CONCLUSION: In this study, a threshold IAP of 20 mm Hg and its permanence over time were the best predictive factors of complications and mortality. Among other relationships, we also observed that older patients had higher IAP. High IAP was a cause of intolerance to enteral nutrition.

A PDA-based flexible telecommunication system for telemedicine applications.

Technology has been used to deliver health care at a distance for many years. Telemedicine is a rapidly growing area and recently there are studies devoted to prehospital care of patients in emergency cases. In this work we have developed a compact, reliable, and low cost PDA-based telecommunication device for telemedicine applications to transmit audio, still images, and vital signs from a remote site to a fixed station such as a clinic or a hospital in real time. This was achieved based on a client-server architecture. A Pocket PC, a miniature camera, and a hands-free microphone were used at the client site and a desktop computer running the Windows XP operating system was used as a server. The server was located at a fixed station. The system was implemented on TCP/IP and HTTP protocol. Field tests have shown that the system can reliably transmit still images, audio, and sample vital signs from a simulated remote site to a fixed station either via a wired or wireless network in real time. The Pocket PC was used at the client site because of its compact size, low cost and processing capabilities.

Crystal structure of 1beta-hydroxy-beta-homopipitzolone (9-hydroxy-2,6,9-trimethyltricyclo[6,3,1,0(1,6)]dodeca-5,10,11,12-tetraone).

C15H18O5 is orthorhombic, P2(1)2(1)2(1). The unit-cell dimensions at 293 K are a = 6.526(3), b = 10.247(4), c = 21.008(13) A, V = 1404.8(12) A3, Dx = 1.316 g/cm3, and Z = 4. The R value is 0.044 for 1288 observed reflections. The A, B and C rings adopt chair, twist, and half-chair conformations. The absolute configuration is inferred from the C6 stereochemistry of (+)-cedrol. The crystal structure is stabilized by an O-H...O hydrogen bond and van der Waals forces.