Composites of ZnO nanoparticles and biomass based activated carbon: adsorption, photocatalytic and antibacterial capacities.

Composite material (AC-ZnO) was prepared by growing ZnO nanoparticles during the production of biomass based-activated carbon (AC) via the incorporation of zinc acetate in the process. Comprehensive analyses confirmed the presence of ZnO nanoparticles over the AC surface and described the particular nature of the composite adsorbent. Methylene blue (MB) equilibrium data fitted the Dubinin-Radushkevich model. The MB adsorption capacity was higher for the bare activated carbons (197.9-188.7 mg/g) than the activated carbons with ZnO nanoparticles (137.6-149.7 mg/g). The adsorption of the MB on the adsorbents is physical because the mean adsorption energy (E) is between 1.76 and 2.00 kJ/mol. Experiments that combine adsorption and photocatalysis were carried out with different loads of adsorbents and with and without UV-light exposure. Photocatalytic activity was identified mostly at the first stage of the adsorption process and, in the case of experiments with less load of the composite AC-ZnO, because the light obstruction effect of the activated carbon is more for higher loads. The ZnO grown over AC improves the adsorption of cations such as Pb, Al and Fe in aqueous phase (polluted river water) and provides antibacterial capacity against Escherichia coli and Salmonella typhimurium.

New vaccines require potent adjuvants like AFPL1 and AFCo1.

Neisseria meningitidis B proteoliposome (AFPL1 when used as adjuvant) and its derivative-Cochleate (AFCo1) contain immunopotentiating and immunomodulating properties and delivery system capacities required for a good adjuvant. Additionally, they contain meningococcal protective antigens and permit packaging of other antigens and pathogen-associated molecular patterns (PAMP). Consequently, we hypothesized that they would function as good vaccine adjuvants for their own antigens and also for non-related antigens. AFPL1 is a detergent-extracted outer membrane vesicle of N. meningitidis B transformed into AFCo1 in calcium environment. Both are produced at Finlay Institute under good manufacture practices (GMP) conditions. We show their exceptional characteristics: combining in the same structure, the potentiator activity, polarizing agents and delivery system capacities; presenting multimeric protein copies; containing multiprotein composition and multi and synergistic PAMP components; acting with incorporated or co-administrated antigens; inducing type I IFN-gamma and IL-12 cytokines suggesting the stimulation of human plasmocytoid precursor and conventional dendritic cells, respectively, inducing a preferential Th1 immune response with TCD4(+), TCD8(+), cross-presentation and cytotoxic T-lymphocyte (CTL) in vivo responses; and functioning by parenteral and mucosal routes. AFPL1-AFCo1 protective protein constitutions permit per se their function as a vaccine. In addition to Phase IV Men BC vaccine, AFPL1 has ended the preclinical stage in an allergy vaccine and is concluding the preclinical stage of a nasal meningococcal vaccine. In conclusion, AFPL1 and AFCo1 induced signal 1, 2 and 3 polarizing to a Th1 (including CTL) response when they acted directly as vaccines or were used as adjuvants with incorporated or co-administered antigens by parenteral or mucosal routes. Both are very promising adjuvants.

Competency-based instruction to improve the surgical resident technique and accuracy of the trauma ultrasound.

In a surgical trauma center, programs and workshops have improved the performance on focused abdominal sonogram for trauma (FAST). The purpose of this single-blind study was to prove that a cadaver laboratory competency-based instruction program may be an effective method of FAST training to acquire the skills that would be applied in the trauma room. The study was divided in two parts, laboratory and clinical. Nine surgical residents were divided into two groups: Group I performed the test only once, and Group II performed the training twice. A third "group" was the senior ultrasound technician, whose readings served as our "gold standard" with which to compare the resident readings (Group III). Using cadavers, a 2-cm catheter was introduced into the peritoneal cavity. Sequential aliquots of normal saline were introduced into the abdominal cavity at 0-, 200-, 400-, 600-, and 1000-cc increments in each group tested. The residents were asked to describe their examinations for the presence or absence of fluid in the abdomen. The ultrasound examination was then performed with the cadaver in three different positions to study if there was any difference of fluid detection in varied positions. True positive, true negative, and accuracy were then calculated comparing the three different groups of test sonographers. In the second part of the study, the same residents were then followed in the trauma room, where they performed the FAST in the absence of the ultrasound technician during emergencies. As in the laboratory, the accuracy of their reading compared with that of the ultrasound technician was also evaluated. From 400 cc and upward, Group II began having an overall significantly superior accuracy than the first group and the technician in most quadrants examined. The trend was apparent for more accurate results in all quadrants and positions by all groups as the fluid was increased. Overall, group II was most superior in detection of intra-abdominal fluid in the cadaver. In the clinical scenario, the residents as a whole had similar accuracy (92% vs 96%) in reading FAST as the ultrasound technician. Our results suggest that surgical residents have the ability to detect fluid in the abdomen, there exists a fast learning curve, and the minimum detection level of fluid was between 200 and 400 cc in the peritoneal cavity in the laboratory. Surgical residents were able to detect intra-abdominal fluid in the trauma situation, as shown by the 92 per cent accuracy of the FAST in the emergency situation. We conclude that a cadaver laboratory training program is an important adjunct to improve the skills of the resident in performing and reading FAST.

Anti M. leprae IgM antibody determination by ultramicroimmunoenzymatic (UMELISA HANSEN) for the diagnosis and monitoring leprosy.

The relationship between the IgM antibody response, antigenic load as well as the clinical improvement after chemotherapy was studied in order to obtain useful data for the early diagnosis and monitoring leprosy. A level of 82% (94/115) agreement was obtained between IgM UMELISA HANSEN and slit-skin smear examination. Discrepant results were observed in 16 patients who showed positive IgM response despite negative by the skin smear examination. In these patients, the IgM response was seen to be associated to the early signal for bacilli recurrence in the skin. In one of these patients the presence of bacilli was demonstrated in the skin, two months after IgM antibodies being detected by UMELISA HANSEN. Also in one of the treated patients positive by both diagnostic techniques, a remarkable decrease in the IgM antibody levels was seen, correlating with a significant clinical improvement. Moreover it was found a direct relationship between the IgM antibody response and bacterial antigenic load, regardless the time elapsed in the disease's evolution.

UltramicroELISA for measuring tetanus antitoxin in human sera.

This article describes a combination of methods--a solid-phase enzyme-linked immunosorbent assay (ELISA) combined with an ultramicroanalytical system (UMAS)--that can be used to measure tetanus antitoxin activity in human sera or plasma. The test, which is rapid and permits analysis of 78 samples of serum per reaction plate with a volume of 10 microL of diluted serum per sample, is proposed as an alternative to the traditional biologic assay in mice based on seroneutralization of a known dose of tetanus toxin. The study reported here compared these two procedures, using them both to evaluate 100 sera from the Clinical Laboratory of the General Calixto García Hospital in Havana, Cuba. The two sets of results showed a high degree of correlation (r = 0.99) when subjected to linear regression analysis (95% CI = 0.985-0.993). These and other findings indicate that the cheap and rapid ultramicroELISA method can perform certain tasks for which the slower and costlier traditional assay is not well suited, such as field evaluation of tetanus toxoid vaccines and identification of hyperimmune plasmas appropriate for use in producing specific antitetanus immunoglobulin.

[Ultramicro-ELISA for measuring tetanus antitoxin in human serum]. / UltramicroELISA para medir antitoxina tetánica en suero humano.

A solid-phase enzyme immunoassay (ELISA) for measuring tetanus antitoxin activity in human serum is described; the assay is based on a combination of the indirect method and ultramicro analysis. This rapid test, which has the capacity to analyze 78 blood samples per reagent plate (at a volume of 10 microL of diluted serum per sample), is proposed as an alternative to the traditional mouse bioassay system based on the neutralization of a known dose of tetanus toxin. Results from both tests showed a high correlation in the lineal regression analysis (r = 0.99; CI95%: 0.985 to 0.993). It is recommended that the ultramicro ELISA assay be used in the field to evaluate tetanus toxoid vaccines and to identify hyperimmune plasmas suitable for producing antitetanus immunoglobulin.

[Ultramicro ELISA to the detection of IgM antibodies in Mycobacterium leprae using dry blood samples]. / UltramicroELISA para la detección de anticuerpos IgM al Mycobacterium leprae utilizando muestras de sangre seca.

In this work the adequate conditions for the detection of IgM antibodies to PGL-I in eluates from dried blood spots using the UMELISA HANSEN and the SUMA technology are established. A total of 300 blood donors and 58 leprosy patients samples were studied. For both populations, in the previously established conditions, we compared the results of the eluates from dried blood spots with the serum samples, and was obtained a correlation of 0.919 in blood donors, 0.969 in patients, and 0.954 for the total of both populations. It was also obtained a level of agreement of 98% in patients and 96% in blood donors. In the patients population was found a sensitivity of 93% and an specificity of 100% for the eluates of dried blood spots evaluated by the UMELISA HANSEN in the comparison with the serum samples analized by the same assay.

Prevention of allergic diseases and IgE dosification in cord sera.

In 1986, a Program on Prevention of Allergic Diseases was initiated in our country which was possible on account of the organization conditions of our health system. The program includes IgE measurement in umbilical cord serum by means of an ultramicroanalytic technique for IgE quantification. This is an heterogeneous sandwich-type immunoassay that requires only 10 microliters of reactive on each reaction step and its processing is carried out on the Cuban SUMA equipment. Two groups of children were selected and followed-up: group I included 80 one-year-old infants and group II included 60 18-months-old infants. Both groups followed hypoallergenic diets and had minimal exposure to aeroallergens within their microenvironment. Results were compared with those of respective control groups. Compliance of both groups with the prophylactic measures brought about a reduction in the existence of allergic diseases and a comparison with the control groups offered a statistically significant difference (p less than 0.001). Similarly, incidence of asthma was found more reduced in groups I and II than in the control groups (p less than 0.001). Within the groups treated under the Program on Prevention of Allergic Diseases, IgE values were lower, while the control groups exhibited a higher number of infants with figures of 200 IU/ml or more (p less than 0.05). Our results support the usefulness of preventive measures in avoiding the presence of atopic diseases.