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Rivaroxaban is an anticoagulant (orally active direct Xa inhibitor) considered to reduce the risk of stroke and systemic embolism and treat deep vein thrombosis, pulmonary embolism, and other cardiovascular complications. Bioanalytical methods for rivaroxaban quantification in plasma are necessary for application in pharmacokinetic studies, as well as in drug therapeutic monitoring. In this work, we developed and validated a sensitive bioanalytical method using LC-MS/MS for rivaroxaban quantification in human plasma using an one-step liquid-liquid extraction. The linear concentration range was 1-600 ng/mL. The bioanalytical method was also applied to pharmacokinetic studies in healthy volunteers under fasting and fed conditions. The results demonstrated that the method is rapid, sensitive, and adequate for application in pharmacokinetic studies.

The objective of this study was to develop a dissolution test in order to establish an in vitro–in vivo correlation (IVIVC) model for desvenlafaxine succinate monohydrate (DVSM) extended release (ER) tablets. The in vitro release characteristics of the drug were determined using USP apparatus 1 at 75 rpm, with volume of HCl pH 1.2, acetate buffer solution (ABS) pH 4.5, or phosphate buffer solution (PBS) pH 6.8. In vivo plasma concentrations and pharmacokinetic parameters in healthy volunteers were obtained from a bioequivalence study. The similarity factors f1 and f2 were used to compare the dissolution data. The IVIVC model was developed using fraction dissolved and fraction absorbed of the reference product. For predictability, the results showed that the percentage prediction error (%PE) value of Cmax was 7.63%. The observed low prediction error for Cmax demonstrated that the IVIVC model was valid for this parameter.

The aim of the present study was to bring additional evidence regarding a biopredictive dissolution medium containing 1% sodium lauryl sulphate (SLS) to predict the in vivo behavior of carbamazepine (CBZ) products. Twelve healthy volunteers took one immediate release (IR) dose of either test and reference formulations in a bioequivalence study (BE). Dissolution profiles were carried-out using the medium. Level A in vitro&ndash, in vivo correlations (IVIVC) were established using both one-step and two-step approaches as well as exploring the time-scaling approach to account for the differences in dissolution rate in vitro versus in vivo. A detailed step by step calculation was provided to clearly illustrate all the procedures. The results show additional evidence that the medium containing 1% SLS can be classified as a universal biopredictive dissolution tool, and that both of the approaches used to develop the IVIVC (one and two-steps) provide good in vivo predictability. Therefore, this biopredictive medium could be a highly relevant tool in Latin-American countries to ensure and check the quality of their CBZ marketed products for which BE studies were not requested by their regulatory health authorities.

Aim: The combination of levodopa with carbidopa has been used for treatment of Parkinson's disease being an important therapy in dopamine level control in the brain. Both are very polar compounds becoming a challenge for analysis by LC–MS/MS.Materials & methods: In this work, it was developed and validated a sensitive bioanalytical method by UHPLC–MS/MS for simultaneous levodopa and carbidopa quantification in human plasma using a fast protein precipitation method. Moreover, the bioanalytical method was applied to a pharmacokinetic study in healthy volunteers. Results/Conclusion: The results demonstrated a sensitive and adequate method for application to pharmacokinetic/bioequivalence studies.

In vitro - in vivo correlation (IVIVC) allows prediction of the in vivo performance of a pharmaceutical product based on its in vitro drug release profiles and can be used to optimize formulations, set dissolution limits, reduce the number of bioequivalence studies during product development, and facilitate certain regulatory decisions. This review article aimed to assess papers published in the last two decades regarding the use of the IVIVC in the development of oral formulations, to demonstrate the scenario in this area, as well as to describe the main characteristics of the assessed studies. A systematic search of PubMed and Web of Science databases was conducted to retrieve articles reporting the use of the IVIVC in the oral formulation development in the period from 1998 to 2018. The qualified studies were abstracted regarding drug name, dosage form, BCS class, in vitro and in vivo data, level of IVIVC, number of formulations, presence of the validation and predictability. The discussion was supported by these data, which allowed to address broadly strengths and weaknesses in this area. Moreover, a large database has been described in this article containing different IVIVC models, with different substances, providing support to scientists interested in this area.

Clonazepam is a benzodiazepine commonly prescribed to treat panic disorder, epilepsy, anxiety, depression and certain types of seizures. This study aimed to evaluate the bioequivalence between two formulations of clonazepam tablets in order to meet regulatory requirements for marketing in Colombia and other countries in Latin America. An open-label, randomized, single-dose, two-period, two-sequence, two-treatment crossover study was conducted in 36 healthy subjects of both genders. Subjects received a single dose of clonazepam 2 mg test tablet (Sanofi-Aventis de Colombia S.A.) and reference product (Rivotril®, Produtos Roche Químicos e Farmacêuticos S.A.) under fasting conditions according to a randomly assigned order with a 21-day washout period. Serial blood samples were collected up to 96 h post-dose. Plasma concentrations of clonazepam were obtained by a validated liquid chromatography-tandem mass spectrometry method. Pharmacokinetic parameters were calculated using non-compartmental methods. A total of 36 healthy subjects were enrolled and 31 of them completed the study. Twenty-nine adverse events were reported (11 events with test product

Lipases are one of the most used enzymes in the pharmaceutical industry due to their efficiency in organic syntheses, mainly in the production of enantiopure drugs. From an industrial viewpoint, the selection of an efficient expression system and host for recombinant lipase production is highly important. The most used hosts are Escherichia coli and Komagataella phaffii (previously known as Pichia pastoris) and less often reported Bacillus and Aspergillus strains. The use of efficient expression systems to overproduce homologous or heterologous lipases often require the use of strong promoters and the co-expression of chaperones. Protein engineering techniques, including rational design and directed evolution, are the most reported strategies for improving lipase characteristics. Additionally, lipases can be immobilized in different supports that enable improved properties and enzyme reuse. Here, we review approaches for strain and protein engineering, immobilization and the application of lipases in the pharmaceutical industry.

Myopathy is a well-known side effect of corticosteroid therapy. Creatine monohydrate (Cr) supplementation has been shown to increase fat-free mass and muscular function. This study aimed to investigate if Cr administration could offset the deleterious functional effects of high doses of steroids. Fifty-six male Syrian golden hamsters were randomized among 4 groups: GI (n = 10), subcutaneous (s.c.) and intraperitoneal (i.p.) saline; GII (n = 10), s.c. saline and i.p. Cr (600 mg·kg–1·d–1); GIII (n = 18), s.c. dexamethasone (7.5 mg·kg–1·d–1) and i.p. saline; and GIV (n = 18), s.c. dexamethasone and i.p. Cr. Daily voluntary running was measured using activity wheels for 18 d. At the end of the study, statistically significant differences in running were observed between all groups, except for GI versus GII (GI, 8878 ± 2737 m; GII, 9145 ± 2000 m; GIII, 4289 ± 2623 m; GIV, 6339 ± 2345 m). Dexamethasone led to a significant decrease in cross-sectional area of type II fibers of the medial gastrocnemius. The cross-sectional area of type I fibers was significantly larger in GIV than in GIII. In conclusion, Cr administration attenuated the impairment of daily spontaneous running of hamsters receiving a high dose of corticosteroids. Additional research is needed to clarify the clinical implications of this finding.

An expression library was constructed from an Actinobacillus pleuropneumoniae serotype 1 clinical isolate using a plasmid vector. The library was screened with serum raised against the culture supernatant of this strain. One Escherichia coli transformant which also reacted with convalescent serum was isolated and found to express a protein with an electrophoretic mobility of approximately 50,000. The A. pleuropneumoniae-derived DNA encoding the protein was localized and characterized by nucleotide sequence analysis and primer extension mapping. One open reading frame of 1,095 bases was detected and confirmed by TnphoA insertion mutagenesis. It encoded a protein with a calculated molecular mass of 40 kDa which was lipid modified and present in the outer membrane and in membrane blebs of A. pleuropneumoniae. This protein was designated as outer membrane lipoprotein A (OmlA), and the encoding gene as omlA. Southern blotting under low-stringency conditions revealed the presence of hybridizing sequences in all A. pleuropneumoniae type strains, and a specific serum detected a homologous protein in serotypes 2, 8, 9, 11, and 12 type strains. Pigs immunized with this recombinant protein preparation were protected from death in an aerosol challenge experiment with an A. pleuropneumoniae serotype 1 isolate.

Two Actinobacillus pleuropneumoniae serotype 7 antigens were expressed in Escherichia coli and tested for their protective efficacy in an experimental pig model. The antigens used were a fusion protein containing the carboxy-terminal 70% of the +/- 103 kDa cytolysin and a full length 60 kDa protein which has been shown previously to bind transferrin. Pigs were immunized twice with 25 micrograms of either or both preparations. All pigs developed a strong humoral immune response comparable to that induced by infection. Upon challenge with an A. pleuropneumoniae serotype 7 strain, all immunized groups were less affected by the disease and showed significantly lower mortality than the controls (p less than 0.1). Pigs receiving both antigens had a tendency to recover faster than the controls or animals which were vaccinated with only one antigen. Protection was serotype-specific since no cross-protection was detected following challenge with an A. pleuropneumoniae serotype 1 strain. A dose-response experiment using the single antigens at 200, 50 or 12.5 micrograms per dose showed no difference in protection among the groups.

O trabalho que segue, MEU CORPO É UM ACONTECIMENTO, dissertação apresentada ao Curso de Mestrado em Artes da Escola de Belas Artes/UFMG, investiga o corpo na primeira pessoa. Objeto e sujeito da ação, o corpo sensível faz do ato um acontecimento. Assim, aborda questões, tais quais: a arte da performance, a fotografia, o vídeo, os gestos do artista, o tempo, o lugar, o individual e o global, os afetos e percepções, a realidade e a virtualidade, objetivando uma análise capaz de confluir teoria e prática, arte e vida. Como suporte para a pesquisa, estuda o pensamento como um elemento construtor de mundos e suas implicações conceituais, inseridas na contemporaneidade. Os desdobramentos, advindos de tal reflexão, são os elementos construtores dessa escrita. MY BOBY IS AN OCCURRENCE, dissertation submitted to the Escola de Belas Artes/UFMG for the Master degree in Visual Arts, investigates the body in the first person speech. Action object and subject, my sensitive body turns the act into an occurrence. This way, I deal with relevant matters, such as: the performance art, the photography, the video, the artists gestures, the time, the place, the individual and the global, the affections and perceptions, the reality and virtuality, focusing an analysis capable of converge theory and practice, art and life. As the recherche support, it is studied the thought as a construction element of worlds and its conceptual implications, inserted in the contemporaneity. The developments, came out from such reflexion, are the constructive elements of this writing.

Recovery from infection involves a number of complex interactions between specific cells of the immune system. Many of these interactions are mediated by cytokines, which can activate these cells to kill or reduce the replication rate of the pathogen. Availability of large quantities of recombinant cytokines has provided the opportunity to investigate the mechanism or mechanisms of action of each cytokine in vitro and in vivo. In the present review, we describe the application of interferons to reduce morbidity and mortality of cattle suffering from bovine respiratory disease and mastitis. The potential application of interferons in disease modulation as well as the impediments to their use are discussed.

These studies were done to develop a subunit vaccine for swine that would protect against disease, but not create unacceptable tissue reactions at the immunization site. Swine were used to evaluate the local effects of subunit vaccines prepared from extracts of Actinobacillus pleuropneumoniae serotype 1 containing one of a wide variety of adjuvants. The antigen was an anionic fraction of a saline extract of A. pleuropneumoniae (ANEX). The adjuvants used were vegetable oils (peanut, sesame, canola, or corn oils, vitamin E, or Lipposyn II emulsion); mineral oil (Marcol-52) and other materials (aluminum hydroxide, polyethylene glycol, Quil-A, Amphigen, or Emulsigen-Plus). Two types of experiments were done. In the 1st set of experiments, pigs were given multiple simultaneous injections in different sites and euthanized on days 1, 3, 7, 14, 21, or 28. Tissues were examined for gross and histopathological lesions. In the 2nd set of experiments, 48 pigs were allocated to 6 groups and vaccinated twice with a vaccine containing ANEX antigen combined with one of various adjuvants. Antibody responses and protection from challenge were evaluated. Among the adjuvants that were tested, mineral oils induced protective immunity, although the mineral oil Marcol-52 resulted in severe tissue reactions. The vegetable oils induced little protective immunity, and some of them were quite irritating. The response to the other materials ranged from little irritation or protection induced by the vaccine containing aluminum hydroxide to effective protection without irritation after vaccination with ANEX/Amphigen or ANEX/Emulsigen-Plus combinations. In conclusion, swine were protected against disease by a subunit vaccine that did not create unacceptable tissue reaction at the immunization site.

Recombinant bovine interferon-alpha I1 (rBoIFN-alpha) has known antiviral and immunomodulatory effects which have been exploited to reduce clinical disease in a number of clinical situations including bovine respiratory diseases. A slow release rBoIFN-alpha formulation may be of value to reduce bovine respiratory disease under field conditions by extending the period of protection, and hence improving the prophylactic benefits of rBoIFN-alpha. In this report, we describe a formulation of rBoIFN-alpha in sesame oil containing calcium stearate which can successfully sustain the release of rBoIFN-alpha over an 8-day period. Recombinant bovine IFN-alpha could be measured in serum for 8 days following treatment with an initial burst of release 6 h after injection. After a single subcutaneous depot injection of 50 mg and 100 mg of rBoIFN-alpha, initial serum levels reached 12-15 ng/ml and 25 ng/ml respectively. Correlating with this burst of release, there was a decrease in the number of circulating CD4-CD8- gamma delta+ T lymphocytes, and a slight neutropenia. No alterations in other cell phenotypes tested (CD4, CD8, CD2, CD6, B cells, monocytes or MHC class II) were observed, nor were there changes in lymphokine activated killer (LAK), natural killer (NK) cell activity, or oxygen radical formation (assessed by reduction of nitroblue tetrazolium). However, despite the rapid and short-lived burst of rBoIFN-alpha, levels of 2-5 oligoadenylate (2-5 A) synthetase remained elevated for 8 days. The sustained increase of 2-5 A synthetase was not due to the high initial dose released during the burst 6-12 h after injection, since injection of a bioavailable equivalent dose of interferon induced a significant rise in 2-5 A synthetase activity for 4 days only. As 2-5 A synthetase is known to be a correlate of antiviral activity, we propose that this formulation of rBoIFN-alpha may be one approach to increase the window of protection, leading to more effective prevention of bovine respiratory disease.

Recombinant bovine interleukin-2 (rBoIL-2) was administered as a single intramuscular bolus to healthy calves to determine the minimal dose capable of exerting a biological response. Doses ranging from 2.5 to 0.05 micrograms rBoIL-2/kg did not induce pyrexia, diarrhea, or depression, nor did they alter any blood chemistry or hematological parameters commonly associated with IL-2 toxicity. Moreover, the only significant immunological change observed was a reduction in the number of peripheral blood lymphocytes identified with the monoclonal antibodies B7A, BAQ4A (WC1+ cells), CACTB6A (WC2+ cells) and DH59B (monocytes). The decrease in cells associated with these markers did not influence non-MHC restricted cytotoxicity or in vitro lymphocyte proliferative responses to mitogens and IL-2. The treatments had no effect on delayed type hypersensitivity responses to phytohemagglutinin. These results indicate that IL-2 may be involved in the regulation of trafficking patterns of a unique subpopulation of lymphocytes in cattle.