RESUMEN
The concept of manufacturing valuable bacterial nanocellulose (BNC) from plant raw materials having a zero prime cost is substantiated. The process flowsheet involves the chemical transformation of the feedstock to obtain a pulp; enzymatic hydrolysis of the pulp to furnish a solution of reducing sugars, chiefly glucose; preparation of a nutrient broth based on the enzymatic hydrolysate; biosynthesis of nanocellulose microfibrils by the symbiotic Medusomyces gisevii Sa-12 culture; and purification of BNC. BNC has for the first time been synthesized from oat hulls and has a high degree of crystallinity of 88 ± 5% and is composed of 99% Iα-allomorph.
Asunto(s)
Bacterias/metabolismo , Celulosa/biosíntesis , Nanopartículas/química , Nanotecnología/métodos , Avena/química , Celulosa/química , Celulosa/economía , Nanotecnología/economía , Plantas/químicaRESUMEN
In this work, X-ray studies of the amorphous oxide films obtained by thermal evaporation of WO(3) powder in a vacuum and by anodic oxidation were carried out. X-ray diffraction patterns were obtained in the symmetric reflection geometry on a DRON-4 diffractometer (Mo K(alpha) radiation, LiF monochromator) in automatic mode. Molecular dynamics simulation of amorphous tungsten oxide atomic configurations has been carried out in the micro-canonical ensemble (NVE) for N = 208 atoms and N = 624 atoms, in a cubic cell, using pairwise Born-Mayer interaction potentials and periodic boundary conditions. One of the purposes of the present work is to analyze the influence of the parameters and the cutoff of the interaction potentials on the interatomic distances. The values obtained in the molecular dynamics simulation for the pair functions D(r) are compared with the experimental data for amorphous oxides in order to choose the most convenient aforesaid values. The values of the average interatomic distances and the coordination numbers obtained by both methods are also compared. The result shows that the tungsten subsystem can be well reproduced using the potential cutoff radius of about 4 A, but the oxygen subsystem can be well reproduced when the cutoff of the potential for the W-O pairs is equal to 2.8 A. The configuration built during the molecular dynamics experiment consists of distorted octahedra. These octahedra form chains, as in the WO(3) phases of type ReO(3), and hexagonal rings, of the same type as in the WO(3)(1/3)H(2)O phase, when we extract (1/3)O at every WO(3) unit. The pair function D(r) and scattering intensity I(s) distribution curves calculated for simulation configurations show a satisfactory agreement with experiment.
RESUMEN
The investigation was concerned with diagnostic sensitivity, specificity and effectiveness of assay of CA 19-9 and carcinoembryonic antigen (CEA) in the choice of treatment modality and evaluation of therapy pancreatic carcinoma (PC). Either marker has been studied in 685 examinations for PC, 68--chronic pseudotumorous pancreatitis and 24--intestinal cancer at other sites since 1995. Tumor resection for PC was carried out in 31; conservative treatment--67; chemotherapy--56 and radiotherapy--in 29 cases. In CA 19-9 examinations, diagnostic sensitivity was 90.2; specificity--72.1 and effectiveness--85.3%, while in CEA determinations, 82.5; 30.9 and 68.5%, respectively. CA 19-9 and CEA levels proved to be prognostic factors of survival. An inverse correlation was observed between median survival and tumor marker concentrations: higher basal (preoperative) level of marker in blood was matched by lower median survival. A similar relationship was identified for CEA: 5-10--14.2 months; 10.1-20 ng/ml--8.0 months; 20.1-30 ng/ml--3.9 months, and more than 30 ng/ml--4.8 months. There was a direct correlation between CA 19-9 level and tumor stage. The dynamics of tumor markers, particularly, CA 19-9 correlated with treatment effectiveness during its course.
Asunto(s)
Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/sangre , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Terapia Combinada , Diagnóstico Diferencial , Humanos , Estadificación de Neoplasias , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Valor Predictivo de las Pruebas , Pronóstico , Sensibilidad y Especificidad , Análisis de SupervivenciaRESUMEN
The characteristics of nonspecific immunity were studied on an outpatient material of 80 non-smoking women aged 38-60 years, with manifestations of hereditary primary enzymopathy (hyperoxaluria syndrome). Hyperoxaluria was shown to be related to immunologic imbalance of some components of nonspecific resistance by the cellular and humoral type. In addition to biochemical differences, the group of patients with prognostically favourable chronic asthmatic bronchitis have got immunologic differences with the alternative group.