Optimization of a Therapeutic Vaccine Candidate by Studying Routes, Immunization Schedules and Antigen Doses in HBsAg-positive Transgenic Mice

Hepatitis B core antigens (HBcAg) and hepatitis B surface antigens (HBsAg) are the main structural antigens of hepatitis B virus (HBV). Both antigens are potent immunogens for experimental animals as well as in acutely infected patients. A novel formulation based on the combination of HBsAg and HBcAg has been developed as a therapeutic vaccine candidate, aimed at inducing an immune response capable of controlling the infection. An immunization schedule was conducted to evaluate the immunogenicity of this formulation after simultaneous immunization by the intranasal and parenteral routes using different schedules and doses. Humoral and cellular immune responses generated in blood and spleen were evaluated by engyme-linked immunosorbent assay (ELISA) and enzyme-liked immunospot (ELISPOT) assays respectively. A first experiment evaluated two groups of mice simultaneously immunized by intranasal (IN) and subcutaneous (SC) routes, one including alum by SC route and, in the other, the formulation was injected without adjuvant.

As a result, alum adjuvant did not increase the immunogenicity under the studied conditions. In fact, the group without alum induced the most potent immune response. The immune response was enhanced by combining IN and SC immunization compared to the SC route alone. In a second experiment, mice were immunized by different mucosal routes at the same time, and compared to the simultaneously (IN/SC) immunized groups. It was demonstrated that there is no improvement on the resulting immune response by using multiple routes of immunizations simultaneously; however, the increase of the antigen dose induced a superior immune response. Interestingly, the increase of antigen dose only by SC route did not favor the resulting immunogenicity. In conclusion, the use of HBsAg transgenic mice has proven useful to optimize the formulation, avoiding the unnecessary use of alum as adjuvant as well as provided information of the role of different mucosal immunization routes and antigen dose on the resulting immune response.

How to cite this article: Trujillo H, Blanco A, García D, Freyre F, Aguiar J, Lobaina Y, Aguilar JC. Optimization of a Therapeutic Vaccine Candidate by Studying Routes, Immunization Schedules and Antigen Doses in HBsAg-positive Transgenic Mice. Euroasian J Hepato-Gastroenterol 2014;4(2):70-78.

Implications of genetic selection on yolk proportion on the dry matter content of eggs in a White Leghorn population

1. The responses to genetic selection on yolk proportion as a technique for increasing egg dry matter content, an important criterion for the egg-product industry, was investigated in a pedigree flock of White Leghorn hens. 2. Parents were preselected on high and low yolk proportion from a base population. The absolute estimated breeding value for yolk proportion of both groups differed by 3%. The realised selection difference in dry matter content of eggs between groups was more than 1% in the analysed offspring population. 3. Heritability estimates were moderate and dry matter had a lower heritability (h(2) = 0.39) than yolk proportion (h(2) = 0.44). 4. The genetic correlation between yolk proportion and dry matter content was highly positive (rg = 0.91). Genetic correlations with egg weight were negative and would have to be compensated for in a breeding programme (rg = -0.76 with yolk proportion and rg = -0.64 with dry matter content). The genetic correlation between the laying performance and yolk proportion was rg = 0.28 and close to zero (rg = -0.05) for dry matter content. 5. Easy recording and lower undesirable correlations make yolk proportion more suitable for commercial selection compared with egg dry matter content in layer breeding.

Electrooxidation of industrial wastewater containing 1,4-dioxane in the presence of different salts

The treatment of 1,4-dioxane solution by electrochemical oxidation on boron-doped diamond was studied using a central composite design and the response surface methodology to investigate the use of SO4 (2-) and HCO3 (-) as supporting electrolytes considering the applied electric current, initial chemical oxygen demand (COD) value, and treatment time. Two industrial effluents containing bicarbonate alkalinity, one just carrying 1,4-dioxane (S1), and another one including 1,4-dioxane and 2-methyl-1,3-dioxolane (S2), were treated under optimized conditions and subsequently subjected to biodegradability assays with a Pseudomonas putida culture. Electrooxidation was compared with ozone oxidation (O3) and its combination with hydrogen peroxide (O3/H2O2). Regarding the experimental design, the optimal compromise for maximum COD removal at minimum energy consumption was shown at the maximum tested concentrations of SO4 (2-) and HCO3 (-) (41.6 and 32.8 mEq L(-1), respectively) and the maximum selected initial COD (750 mg L(-1)), applying a current density of 11.9 mA cm(-2) for 3.8 h. Up to 98 % of the COD was removed in the electrooxidation treatment of S1 effluent using 114 kWh per kg of removed COD and about 91 % of the COD from S2 wastewater applying 49 kWh per kg of removed COD. The optimal biodegradability enhancement was achieved after 1 h of electrooxidation treatment. In comparison with O3 and O3/H2O2 alternatives, electrochemical oxidation achieved the fastest degradation rate per oxidant consumption unit, and it also resulted to be the most economical treatment in terms of energy consumption and price per unit of removed COD.

Regulation of corticosterone secretion is modified by PFOS exposure at different levels of the hypothalamic-pituitary-adrenal axis in adult male rats

Perfluorooctane sulfonate (PFOS) is a fluorinated compound and a Persistent Organic Pollutant which can disrupt the endocrine system. This work was undertaken to evaluate the possible effects of PFOS exposure on the regulation of corticosterone secretion in adrenal and pituitary glands and at hypothalamic level in adult male rat, and to evaluate the possible morphological alterations induced by PFOS in this endocrine tissue. Adult male rats were orally treated with 0.5, 1.0, 3.0 and 6.0 mg of PFOS/kg/day for 28 days. Corticosterone, adrenocorticotropic hormone (ACTH) and corticotrophin-releasing hormone (CRH) secretion decreased in PFOS-treated rats. After PFOS exposure, relative expression of adrenocorticotropic hormone receptor (ACTHr) and proopiomelanocortin (POMC) genes was increased in adrenal and in pituitary glands, respectively; while relative expression of ACTHr and CRH genes decreased in hypothalamus with the doses of 0.5 and 1.0 mg/kg/day. PFOS treatment increased relative nitric oxide synthase 1 and 2 (NOS1 and NOS2) gene expression in the adrenal gland, and incremented superoxide dismutase activity. PFOS exposure induces a global inhibition of the hypothalamic-pituitary-adrenal (HPA) axis activity, and small morphological changes were observed in adrenal zona fasciculata cells.

Prolonged incubation time does not increase sensitivity for the diagnosis of implant-related infection using samples prepared by sonication of the implants

We have designed a prospective study to evaluate the usefulness of prolonged incubation of cultures from sonicated orthopaedic implants. During the study period 124 implants from 113 patients were processed (22 osteosynthetic implants, 46 hip prostheses, 54 knee prostheses, and two shoulder prostheses). Of these, 70 patients had clinical infection; 32 had received antibiotics at least seven days before removal of the implant. A total of 54 patients had sonicated samples that produced positive cultures (including four patients without infection). All of them were positive in the first seven days of incubation. No differences were found regarding previous antibiotic treatment when analysing colony counts or days of incubation in the case of a positive result. In our experience, extending incubation of the samples to 14 days does not add more positive results for sonicated orthopaedic implants (hip and knee prosthesis and osteosynthesis implants) compared with a conventional seven-day incubation period.

Cite this article: Bone Joint J 2013;95-B:1001–6.

Photocatalytic degradation of contaminants of concern with composite NF-TiO2 films under visible and solar light

This study reports the synthesis and characterization of composite nitrogen and fluorine co-doped titanium dioxide (NF-TiO(2)) for the removal of contaminants of concern in wastewater under visible and solar light. Monodisperse anatase TiO(2) nanoparticles of different sizes and Evonik P25 were assembled to immobilized NF-TiO(2) by direct incorporation into the sol-gel or by the layer-by-layer technique. The composite films were characterized with X-ray diffraction, high-resolution transmission electron microscopy, environmental scanning electron microscopy, and porosimetry analysis. The photocatalytic degradation of atrazine, carbamazepine, and caffeine was evaluated in a synthetic water solution and in an effluent from a hybrid biological concentrator reactor (BCR). Minor aggregation and improved distribution of monodisperse titania particles was obtained with NF-TiO(2)-monodisperse (10 and 50 nm) from the layer-by-layer technique than with NF-TiO(2) +monodisperse TiO(2) (300 nm) directly incorporated into the sol. The photocatalysts synthesized with the layer-by-layer method achieved significantly higher degradation rates in contrast with NF-TiO(2)-monodisperse titania (300 nm) and slightly faster values when compared with NF-TiO(2)-P25. Using NF-TiO(2) layer-by-layer with monodisperse TiO(2) (50 nm) under solar light irradiation, the respective degradation rates in synthetic water and BCR effluent were 14.6 and 9.5 × 10(-3) min(-1) for caffeine, 12.5 and 9.0 × 10(-3) min(-1) for carbamazepine, and 10.9 and 5.8 × 10(-3) min(-1) for atrazine. These results suggest that the layer-by-layer technique is a promising method for the synthesis of composite TiO(2)-based films compared to the direct addition of nanoparticles into the sol.

[Right lower quadrant abdominal pain--the usual suspects? Diagnosis and therapy of a symptomatic mesenteric cyst]

HISTORY AND CLINICAL FINDINGS

A 17-year-old male sought medical attention for right lower abdominal pain. At clinical examination an abdominal mass in the right lower abdominal quadrant was accompanied by pain and tenderness in this very region. The febrile patient (temperature axillary: 37.5 °C, rectal: 38.6 °C) was in reduced general health.

INVESTIGATIONS

Except for an elevated C-reactive protein (CRP: 14.3 mg/dl, normal: < 0.5) laboratory tests were inconspicuous. Abdominal ultrasound showed a hypoechogenic/anechogenic septated mass measuring 7.2 × 10.4 × 15 cm as well as small amounts of fluid. Abdominal computed tomography confirmed these findings. Radiographically there was evidence for appendicitis.

TREATMENT AND COURSE

Empiric antibiotic therapy was immediately commenced. Within 48 hours laparotomy was performed showing an abdominal mass which seemed to infiltrate the transverse colon, the ileocolic artery and the mesenteric root. No signs of appendicitis were found. A radical resection of the abdominal mass was performed meeting current standards of oncologic surgery. The postoperative course was favourable. Histopathological investigation showed a mesenteric cyst incorporating a hematoma and tissue with signs of chronic inflammation and granulation.

CONCLUSION

Mesenteric cysts are rare pathologies occurring most frequently during childhood. They may become clinically overt in case of infection, haemorrhage or secondary intestinal obstruction. In the presented case presented hematoma formation and chronic inflammation had presumably induced peritonitis and clinical signs of appendicitis. Abdominal ultrasound and computed tomography facilitated diagnostic work-up. The patient thereby benefited from a scheduled laparotomy allowing a complete recovery.

[Final voluntary assessment for Traumatology and Orthopaedic Surgery medical residents: a report on the results and a look at the future]

INTRODUCTION

The idea of establishing an examination that accredits the training of the specialists in orthopaedic surgery at the end of their educational period as residents is subject to controversy. With the aim of encouraging the development of this examination, the present members of the National Commission of the Specialty of Orthopaedics (CNE) have reviewed the results obtained in previous examination.

MATERIALS AND METHODS

The results of the voluntary final exam for Orthopaedics residents, and of the surveys of participant opinions for the years 2006 to 2011 are presented.

RESULTS

The total number of participants was 231, growing from 19 in 2005, to 71 in 2011. The overall mean score in the period reviewed (2006-2011) was 6.72 out of 10 points. In these 6 years, 9 participants failed (4.25%). The mean score for the test was 7.57. The overall mean score of the oral exam was 6.57. The worst results were obtained in the general knowledge section of the oral examination. Nobody has ever failed the section on reconstruction of the lower extremity. The upper extremity section in the oral examination achieves the best average results.

DISCUSSION

The examination has established its place in the structure of orthopaedic resident training in our country, even without making it official by the Administration. We must positively acknowledge those candidates who chose to take the examination and be evaluated by their peers in order to prove their qualification and distinction. This recognition will be the best encouragement for future generations.

Nanoscale Morphology of Water in Silica Colloidal Crystals

We show a simple method to visualize the morphology of water adsorbed within the pore network of colloidal crystals made of submicrometer silica spheres. Water is replicated into silica by modified silicon tetrachloride hydrolysation under standard ambient conditions, making it visible to standard electronic microscopy and thus allowing one to discern the original water distribution. Different distribution patterns are identified depending on the water content, surface condition, and spheres arrangement. The dimension and shape of wetting layers (covering the submicrometer spheres) and capillary bridges (joining them) are measurable at the nanoscale. We finally use these findings to demonstrate proof-of-principle of fabrication of isolated and freestanding silica nanorings by using hydrophobic polymeric templates and selective etching.