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1.
Braz J Biol ; 84: e281448, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695423

RESUMO

Bacterial contamination causes irreparable losses in the performance of alcoholic fermentation. Antibiotics are used to control these microorganisms, but they generate residues and cause microbial resistance. Today the only commercial product used by the mills is hops, but it is very expensive. As an alternative, the objective of this work was to evaluate the feasibility of using extracts from plants grown in the Cerrado for antimicrobial control during an alcoholic fermentation to replace antibiotics. Hydraethanolic extracts of leaves and essential oil of the following species were tested: Schinus terebinthifolius Raddi, Serjania erecta, Serjania marginata, Campomanesia adamantium and Syzygium cumini. Only the extract of Serjania marginata did not show any activity against the bacterium Bacillus sp. Both the essential oils as well as the hydroalcoholic extracts of S. terebinthifolius and C. adamantium and the extract of S. erecta showed antibacterial activity without harming the yeast, with potential to replace the hops.


Assuntos
Fermentação , Extratos Vegetais , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Bacillus , Óleos Voláteis/farmacologia , Testes de Sensibilidade Microbiana , Bactérias/efeitos dos fármacos
5.
Braz J Med Biol Res ; 52(12): e8576, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800730

RESUMO

Physical exercise is a known preventive and therapeutic alternative for several cerebrovascular diseases. Therefore, the objective of the present study was to evaluate the motor performance and histomorphometry of the biceps brachii, soleus, and tibialis anterior muscles of rats submitted to a treadmill training program prior to the induction of cerebral ischemia via occlusion of the middle cerebral artery (OMCA). A total of 24 Wistar rats were distributed into four groups: Sham-Sed: sedentary control animals (n=6), who underwent sham surgery (in which OMCA did not occur); Sham+Ex: control animals exercised before the sham surgery (n=6); I-Sed: sedentary animals with cerebral ischemia (n=6); and I+Ex: animals exercised before the induction of ischemia (n=6). The physical exercise consisted of treadmill training for five weeks, 30 min/day (5 days/week), at a speed of 14 m/min. The results showed that the type-I fibers presented greater fiber area in the exercised ischemic group (I+Ex: 2347.96±202.77 µm2) compared to the other groups (Sham-Sed: 1676.46±132.21 µm2; Sham+Ex: 1647.63±191.09 µm2; I+Ex: 1566.93±185.09 µm2; P=0.0002). Our findings suggested that the angiogenesis process may have influenced muscle recovery and reduced muscle atrophy of type-I fibers in the animals that exercised before cerebral ischemia.


Assuntos
Isquemia Encefálica/complicações , Infarto da Artéria Cerebral Média , Músculo Esquelético/fisiopatologia , Atrofia Muscular/prevenção & controle , Condicionamento Físico Animal/fisiologia , Animais , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Masculino , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Ratos , Ratos Wistar
6.
Heliyon ; 5(7): e02166, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31388589

RESUMO

Endocrine monitoring of non-human primates (NHP) via faecal metabolites of steroid hormones appears as a useful non-invasive alternative to evaluate the reproductive status of free living NHP, as well as of those kept in captivity but of difficult handling. However, validation is needed with plasma values before its application in the field. The aim of the present study was to monitor the different phases of the menstrual cycle from the new world NHP Sapajus apella and S. libidinosus. For this, hormonal and faecal plasma levels of E2, P4 and cortisol were assessed during different days of the menstrual cycle, together with colpocitology. The mean duration of the menstrual cycle according colpocitology was of 21.7 and 21.0 days for S. apella and S. libidinosus, respectively. These values were similar to those observed via plasma analysis, i.e. 22.7 and 20.3 days for S. apella and S. libidinosus, respectively. The day of plasmatic E2 peak was set as Day -1 and the estimated day of ovulation was set as Day 0 and occurred two days earlier in S. libidinosus than in S. apella females. In both species, it was observed a delay in faecal E2 peak of six days for S. apella and of 11 days for S. libidinosus when compared with the plasma peak. A maximum P4 plasma concentration was observed in the middle of luteal phase in S. apella and in S. libidinosus, both at around day 5. However, faecal P4 peaks were detected at days 9 and 8 in S. apella and S. libidinosus, respectively. Mean plasma and faecal cortisol levels were variable during all ovulatory cycle of S. apella and S. libidinosus females. Although no exact correlation was observed between plasmatic and faecal profile of steroid hormone, faecal samples were able to indicate ovarian cycle phase, being important to assess the reproductive status of the females applying a non-invasive method.

7.
Microb Pathog ; 130: 259-270, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30917922

RESUMO

Fruits are among the main natural sources of phenolic compounds (PC). These compounds exert important antioxidant properties primarily associated with the presence of hydroxyl groups in their molecular structure. Additionally, the antibacterial effects of fruit phenolic-rich extracts or individual PC commonly found in fruits have been an emerging research focus in recent years. This review discusses by first time the available literature regarding the inhibitory effects of fruit PC on pathogenic bacteria, including not only their direct effects on bacterial growth and survival, but also their effects on virulence factors and antibiotic resistance, as well as the possible mechanism underlying these inhibitory properties. The results of the retrieved studies show overall that the antibacterial effects of fruit PC vary with the target bacteria, type of PC and length of exposure to these compounds. The type of solvent and procedures used for extraction and fruit cultivar also seem to influence the antibacterial effects of phenolic-rich fruit extracts. Fruit PC have shown wide-spectrum antibacterial properties besides being effective antibiotic resistance modifying agents in pathogenic bacteria and these effects have shown to be associated with interruption of efflux pump expression/function. Furthermore, fruit PC can cause down regulation of a variety of genes associated with virulence features in pathogenic bacteria. Results of available studies indicate the depolarization and alteration of membrane fluidity as mechanisms underlying the inhibition of pathogenic bacteria by fruit PC. These data reveal fruit PC have potential antimicrobial properties, which should be rationally exploited in solutions to control pathogenic bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Frutas/química , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Antibacterianos/isolamento & purificação , Viabilidade Microbiana/efeitos dos fármacos , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Virulência/efeitos dos fármacos
8.
Braz. j. med. biol. res ; 52(12): e8576, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1055463

RESUMO

Physical exercise is a known preventive and therapeutic alternative for several cerebrovascular diseases. Therefore, the objective of the present study was to evaluate the motor performance and histomorphometry of the biceps brachii, soleus, and tibialis anterior muscles of rats submitted to a treadmill training program prior to the induction of cerebral ischemia via occlusion of the middle cerebral artery (OMCA). A total of 24 Wistar rats were distributed into four groups: Sham-Sed: sedentary control animals (n=6), who underwent sham surgery (in which OMCA did not occur); Sham+Ex: control animals exercised before the sham surgery (n=6); I-Sed: sedentary animals with cerebral ischemia (n=6); and I+Ex: animals exercised before the induction of ischemia (n=6). The physical exercise consisted of treadmill training for five weeks, 30 min/day (5 days/week), at a speed of 14 m/min. The results showed that the type-I fibers presented greater fiber area in the exercised ischemic group (I+Ex: 2347.96±202.77 µm2) compared to the other groups (Sham-Sed: 1676.46±132.21 µm2; Sham+Ex: 1647.63±191.09 µm2; I+Ex: 1566.93±185.09 µm2; P=0.0002). Our findings suggested that the angiogenesis process may have influenced muscle recovery and reduced muscle atrophy of type-I fibers in the animals that exercised before cerebral ischemia.


Assuntos
Animais , Masculino , Ratos , Condicionamento Físico Animal/fisiologia , Atrofia Muscular/prevenção & controle , Isquemia Encefálica/complicações , Músculo Esquelético/fisiopatologia , Infarto da Artéria Cerebral Média , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Isquemia Encefálica/fisiopatologia , Ratos Wistar , Modelos Animais de Doenças
9.
Int J Pharm ; 552(1-2): 7-15, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30244149

RESUMO

The use of tailored particle-based adjuvants constitutes a promising way to enhance antigen-specific humoral and cellular immune responses. However, a thorough understanding of the mechanisms underlying their adjuvanticity is crucial to generate more effective vaccines. We studied the ability of chitosan-aluminum nanoparticles (CH-Al NPs), which combine the immunostimulatory effects of chitosan and aluminum salts, to promote dendritic cell activation, assess their impact on innate and adaptive immune responses, and compare the results to those reported for conventional chitosan particles (CH-Na NPs). All tested CH-NP formulations were capable of modulating cytokine secretion by dendritic cells. CH-Al NPs promoted NLRP3 inflammasome activation, enhancing the release of IL-1ß without significantly inhibiting Th1 and Th17 cell-polarizing cytokines, IL-12p70 or IL-23, and induced DC maturation, but did not promote pro-inflammatory cytokine production on their own. In vivo results showed that mice injected with CH-Al NPs generated a local inflammatory response comparable to that elicited by the vaccine adjuvant alum. Importantly, after subcutaneous immunization with CH-Al NPs combined with the hepatitis B surface antigen (HBsAg), mice developed antigen-specific IgG titers in serum, nasal and vaginal washes. Overall, our results established CH-Al NPs as a potential adjuvant to enhance both innate and adaptive immune responses.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Alumínio/administração & dosagem , Quitosana/administração & dosagem , Antígenos de Superfície da Hepatite B/administração & dosagem , Nanopartículas/administração & dosagem , Animais , Citocinas/imunologia , Feminino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia
10.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1145-1151, set.-out. 2017. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-877304

RESUMO

As neoplasias ovarianas em gatas são raras e, quando relatadas, estão associadas a animais senis, assim como a piometra de causa não iatrogênica. O objetivo deste trabalho foi relatar o caso de uma gata jovem com neoplasia ovariana, tumor de células da granulosa associado ao complexo hiperplasia endometrial cística/piometra (HECP). O animal foi atendido no setor de Reprodução Animal e Obstetrícia Veterinária (RAOV) de um Hospital Veterinário Escola, com histórico de monta natural recente, anorexia, êmese, polidipsia, poliúria e descarga vaginal purulenta. Ao exame físico, observou-se apatia, mucosas ictéricas, aumento de volume da região abdominal e presença de secreção vaginal purulenta. À ultrassonografia, foi visibilizado conteúdo ecogênico no útero diagnóstico de HECP e estrutura ecogênica na cavidade abdominal, na região ovariana, confirmado pelo exame histopatológico como sendo tumor das células da granulosa. A conduta terapêutica adotada foi a cirurgia de ovariossalpingo-histerectomia (OSH).(AU)


Ovarian neoplasias in cats are rare, and are associated with advanced ages, as well as non-iatrogenic pyometra. The objective of the present study was to report a case of a young cat showing signs of a rare neoplasia, the granulosa-cell tumor, associated with complex cystic endometrial hyperplasia/pyometra (HECP). The animal was attended in the Animal Reproduction and Veterinary Obstetrics sector of a Teaching Veterinary Hospital with a history of natural breeding, anorexia, emesis, polydipsia, polyuria, and purulent vaginal discharge. During clinical examination, apathy, icterus, swelling of the abdomen, and purulent vaginal discharge were observed. On the ultrasonographic exam, an echogenic content inside the uterus was observed, leading to diagnosis of HECP and an echogenic structure in the abdominal cavity, in ovarian region, confirmed by histopathology as being of granulosa cells. The therapeutic conduct adopted was salpingo-oophorectomy and hysterectomy surgery (OSH).(AU)


Assuntos
Animais , Feminino , Gatos , Hiperplasia Endometrial/veterinária , Tumor de Células da Granulosa/veterinária , Piometra/veterinária , Neoplasias Ovarianas/veterinária
11.
J Dairy Sci ; 100(10): 8426-8429, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28755949

RESUMO

Goat farming is a low-cost alternative to dairy production in developing countries. In Brazil, goat production has increased in recent years due in part to the implementation of programs encouraging this activity. Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of paratuberculosis, a disease that causes chronic granulomatous enteritis in ruminants, but MAP transmission dynamics are still poorly understood in goats. In a previously published study of our research group, 10 dairy goat farms (467 animals) from Minas Gerais state were analyzed for MAP detection; 2 fecal cultures and 11 milk samples tested positive for MAP by conventional PCR and were confirmed by sequencing. Because no clinical signs were observed over 1 yr of monitoring, we hypothesized that these MAP-positive goats could be passive shedders. Thus, in the present study, 4 positive goats (4/13) from the previous study were purchased and feces and milk samples were collected for evaluation (twice, with an interval of 3 mo between tests) by culture of MAP, IS900 PCR, or both. All analyses were negative for MAP. At the last time point, blood samples were collected for ELISA, the animals were killed, and tissues collected for tissue culture and histopathology. At necropsy, no macroscopic lesions related to paratuberculosis were observed. Similarly, no histological changes were observed and MAP in samples stained by Ziehl-Neelsen was not detected. These animals were characterized as potential passive shedders with upward contamination of the teat canal by MAP. This is the first report of the passive shedding phenomenon in goats in Brazil and it highlights the importance of identifying these animals for control programs and to ensure the quality of dairy products.


Assuntos
Derrame de Bactérias , Doenças das Cabras/microbiologia , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/microbiologia , Animais , Brasil , Fezes/microbiologia , Cabras , Leite/microbiologia
12.
Int J Pharm ; 527(1-2): 103-114, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28522427

RESUMO

The use of particulate adjuvants offers an interesting possibility to enhance and modulate the immune responses elicited by vaccines. Aluminium salts have been extensively used as vaccine adjuvants, but they lack the capacity to induce a strong cellular and mucosal immune response. Taking this into consideration, in this study we designed a new antigen delivery system combining aluminium salts with chitosan. Chitosan-aluminium nanoparticles (CH-Al NPs) exhibited a mean diameter of 280nm and a positive surface charge. The newly developed CH-Al NPs are more stable at physiological environment than classical CH NPs, showing no cytotoxic effects and revealing potential as a delivery system for a wide range of model antigens. In vivo studies showed that mice immunized with hepatitis B surface antigen (HBsAg)-containing CH NPs display high anti-HBsAg IgG titers in the serum, as well as the highest antigen-specific IgG on vaginal washes. Furthermore, in contrast to mice receiving antigen alone, mice immunized with the particulate adjuvant were able to elicit IgG2c antibody titers and exhibited higher antigen-specific IFN-γ levels in splenocytes. In conclusion, we established that CH-Al NPs, combining two immunostimulants to enhance both humoral and cellular immune responses, are a safe and promising system for antigen delivery. Our findings point towards their potential in future vaccination approaches.


Assuntos
Adjuvantes Imunológicos/química , Alumínio/química , Quitosana/química , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Células A549 , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química
13.
Transbound Emerg Dis ; 64(5): e4-e7, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27357532

RESUMO

This report describes a fatal case of a pet dog with major enteric signs owned by a family that has experienced cases of pulmonary tuberculosis (TB) in the household. Clinical and epidemiological aspects, imaging data, microbiological, haematological and histopathological examinations were assessed to diagnosis of disease. gyrB-RFLP, spoligotyping and MIRU-VNTR allowed molecular detection of M. tuberculosis strain from S family. The resazurin microtiter assay indicated that all isolates were resistant to isoniazid, ethambutol, ciprofloxacin, ofloxacin, streptomycin and amikacin. The public health concerns related to canine tuberculosis and risk of the dissemination by pets of M. tuberculosis pre-multidrug-resistant (PMD) to isoniazid, ethambutol and other first-line drugs used in human therapy of TB are discussed. We believe this to be the first report of PMD M. tuberculosis infection in a dog presenting mainly enteric manifestation, confirmed as S lineage by molecular methods, owned by a family in which TB has spread in the household for generations.


Assuntos
Doenças do Cão/microbiologia , Farmacorresistência Bacteriana Múltipla , Enterite/veterinária , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Pulmonar/microbiologia , Animais , Antituberculosos/farmacologia , Doenças do Cão/diagnóstico , Cães , Enterite/diagnóstico , Enterite/microbiologia , Evolução Fatal , Humanos , Isoniazida/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/isolamento & purificação , Animais de Estimação , Tuberculose Resistente a Múltiplos Medicamentos
15.
Int Rev Neurobiol ; 130: 1-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27678173

RESUMO

Central nervous system (CNS) diseases constitute a set of challenging pathological conditions concerning diagnosis and therapeutics. For most of these disorders, there is a lack of early diagnosis, biomarkers to allow proper follow-up of disease progression and effective therapeutic strategies to allow a persistent cure. The poor prognosis of most CNS diseases is, therefore, a global concern, especially regarding chronic age-related neurodegenerative disorders, which are already considered problems of public health due to the increasing average of life expectancy. The difficulties associated with the treatment of CNS diseases are owed, at least in part, to very specific characteristics of the brain and spinal cord, when compared to peripheral organs. In this regard, the CNS is physically and chemically protected by the blood-brain barrier (BBB), which, while maintaining essential brain homeostasis, significantly restricts the delivery of most therapeutic agents to the brain parenchyma. On the other hand, regenerative properties of the tissue are lacking, meaning that a CNS insult resulting in neuronal death is a permanent phenomenon. Approaches for transposing the BBB aiming to treat CNS diseases, relying on specific properties of nanosystems, have been reported for therapeutic delivery to CNS without interfering with the normal function of the brain. In this chapter, we address the latest advances concerning the principles of such approaches, employing lipid-based nanoparticles and cell-produced exosomes as drug and nucleic acid delivery systems, and summarize recent example of applications in the context of neurological diseases. Major achievements obtained in preclinical studies and the trends identified by these studies are emphasized to provide new prospects for further developments in this area, thus enabling us to move from the research realm to the clinical arena.


Assuntos
Doenças do Sistema Nervoso Central/tratamento farmacológico , Exossomos , Nanopartículas/uso terapêutico , Nanotecnologia/tendências , Animais , Sistemas de Liberação de Medicamentos , Humanos , Lipídeos/administração & dosagem , Nanopartículas/administração & dosagem
16.
Bioorg Med Chem ; 24(18): 4228-4240, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27475533

RESUMO

In this study, we designed and synthesized a series of thiophen-2-iminothiazolidine derivatives from thiophen-2-thioureic with good anti-Trypanosoma cruzi activity. Several of the final compounds displayed remarkable trypanocidal activity. The ability of the new compounds to inhibit the activity of the enzyme cruzain, the major cysteine protease of T. cruzi, was also explored. The compounds 3b, 4b, 8b and 8c were the most active derivatives against amastigote form, with significant IC50 values between 9.7 and 6.03µM. The 8c derivative showed the highest potency against cruzain (IC50=2.4µM). Molecular docking study showed that this compound can interact with subsites S1 and S2 simultaneously, and the negative values for the theoretical energy binding (Eb=-7.39kcal·mol(-1)) indicates interaction (via dipole-dipole) between the hybridized sulfur sp(3) atom at the thiazolidine ring and Gly66. Finally, the results suggest that the thiophen-2-iminothiazolidines synthesized are important lead compounds for the continuing battle against Chagas disease.


Assuntos
Tiazolidinas/farmacologia , Tiofenos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Cisteína Endopeptidases , Inibidores de Cisteína Proteinase/síntese química , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/toxicidade , Glicina/química , Camundongos , Simulação de Acoplamento Molecular , Octoxinol , Proteínas de Protozoários/antagonistas & inibidores , Tiazolidinas/síntese química , Tiazolidinas/toxicidade , Tiofenos/síntese química , Tiofenos/toxicidade , Tioureia/análogos & derivados , Tioureia/síntese química , Tioureia/farmacologia , Tioureia/toxicidade , Tripanossomicidas/síntese química , Tripanossomicidas/toxicidade
17.
Phys Chem Chem Phys ; 18(44): 30288-30296, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27341353

RESUMO

The dengue virus (DENV) is the causative agent of the viral infection dengue fever. In spite of all the efforts made to prevent the spread of the disease, once it is contracted, there is no specific treatment for dengue and the WHO guidelines are limited to rest and symptomatic treatment. In its reproductive cycle, DENV utilizes the NS2B-NS3pro, a serine protease, to cleave the viral polyprotein into its constituents. This enzyme is essential for the virus lifecycle, and presents an attractive target for the development of specific dengue treatments. Here we used a hybrid Quantum Mechanics and Molecular Mechanics (QM/MM) Molecular Dynamics approach and Umbrella Sampling to study the first step (acylation) of the reaction catalyzed by NS2B-NS3pro, using the Pairwise Distance Directed Gaussian PM3 (PDDG/PM3) semi-empirical Hamiltonian for the QM subsystem, and Amber ff99SB for the MM subsystem. Our results indicate that the nucleophilic attack on the substrate by Ser135 occurs in a stepwise manner, in which a proton transfer to His51 first activates Ser135, which only later attacks the substrate. The rate-determining step is the Ser135 activation, with a barrier of 24.1 kcal mol-1. Water molecules completing the oxyanion hole stabilize the negative charge formed on the carbonyl oxygen of the substrate. The final step in the process is a proton transfer from His51 to the substrate's nitrogen, which happens with a lower barrier of 5.1 kcal mol-1, and leads directly to the breakage of the peptide bond.


Assuntos
Vírus da Dengue/enzimologia , Simulação de Dinâmica Molecular , Serina Proteases , Proteínas Virais , Catálise
18.
Mol Pharm ; 13(2): 472-82, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26651533

RESUMO

The generation of strong pathogen-specific immune responses at mucosal surfaces where hepatitis B virus (HBV) transmission can occur is still a major challenge. Therefore, new vaccines are urgently needed in order to overcome the limitations of existing parenteral ones. Recent studies show that this may be achieved by intranasal immunization. Chitosan has gained attention as a nonviral gene delivery system; however, its use in vivo is limited due to low transfection efficiency mostly related to strong interaction between the negatively charged DNA and the positively charged chitosan. We hypothesize that the adsorption of negatively charged human serum albumin (HSA) onto the surface of the chitosan particles would facilitate the intracellular release of DNA, enhancing transfection activity. Here, we demonstrate that a robust systemic immune response was induced after vaccination using HSA-loaded chitosan nanoparticle/DNA (HSA-CH NP/DNA) complexes. Furthermore, intranasal immunization with HSA-CH NP/DNA complexes induced HBV specific IgA in nasal and vaginal secretions; no systemic or mucosal responses were detected after immunization with DNA alone. Overall, our results show that chitosan-based DNA complexes elicited both humoral and mucosal immune response, making them an interesting and valuable gene delivery system for nasal vaccination against HBV.


Assuntos
Formação de Anticorpos/imunologia , Quitosana/administração & dosagem , DNA/administração & dosagem , Antígenos de Superfície da Hepatite B/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Nanopartículas/administração & dosagem , Mucosa Nasal/imunologia , Administração Intranasal , Animais , Quitosana/química , DNA/química , Portadores de Fármacos , Feminino , Humanos , Imunização , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/química , Mucosa Nasal/efeitos dos fármacos , Transfecção , Vacinas
19.
Artigo em Português | LILACS | ID: lil-737685

RESUMO

O câncer, ou neoplasia, é uma doença caracterizada pela propagação descontrolada de formas anormais das próprias células corporais e corresponde à segunda doença que mais causa mortes no mundo. A história da platina no tratamento do câncer teve início com a descoberta da sua atividade, em 1965, com a aprovação para uso clínico acontecendo apenas após 10 anos. Atualmente, os fármacos com platina estão entre os mais bem sucedidos agentes anticancerígenos, onde se destacam cisplatina (1), carboplatina (2) e oxaliplatina (3). Seus mecanismos de ação são similares: estes fármacos formam adutos com o DNA, impedindo a sua síntese e reparo, levando à morte celular. Contudo, os efeitos adversos desencadeados pelo tratamento e o desenvolvimento de resistência ao medicamento têm limitado suas aplicações. Uma das principais estratégias para a diminuição de tais efeitos consiste em alterar a estrutura destas moléculas, levando à formação de compostos híbridos, que se caracterizam pela presença de pelo menos dois fragmentos funcionais distintos em uma mesma molécula e podem apresentar maior espectro de atividade antitumoral. Dentre as alterações mais comuns encontram-se a modificação da solubilidade, através da inserção de grupos abandonadores mais ou menos hidrofóbicos e a introdução de ligantes com atividade biológica própria. Dessa forma, esta revisão visa verificar os avanços mais recentes na síntese de compostos híbridos de platina, bem como as melhorias na atividade anticâncer dos novos compostos platinados...


Cancer, or neoplasm, is a disease characterized by the uncontrolled propagation of abnormal cells of the body and is the second leading death-causing disease. The history of platinum in cancer treatment goes back to the discovery of its activity in 1965 and its approval for clinical use just 10 years later. Some of the most successful anticancer agents are Pt-based chemotherapeutics, among which cisplatin (1), carboplatin (2), and oxaliplatin (3) stand out. They have similar mechanisms of action: they form adducts with DNA, preventing its synthesis and repair and leading to cell death. However, adverse effects triggered by treatment and the development of resistance to these drugs have limited their application. One of the most important strategies to reduce such effects is to carry out structural modifications of these molecules, leading to hybrid compounds that are characterized by the presence of at least two distinct functional fragments on the same molecule and can exhibit a broader antitumor activity spectrum. Among the most typical modifications are changes to the solubility pattern, created by the insertion of leaving groups with high or low hydrophobicity, and the introduction of biologically active ligands as non-leaving groups. The purpose of these strategies is to obtain compounds capable of reducing systemic toxicity and/or overcoming acquired resistance factors to cisplatin. Therefore, the aim of this review is to discuss the most recent advances in the synthesis of hybrid platinum compounds, as well as improvements in the anticancer activity of Pt-compounds...


Assuntos
Humanos , Carboplatina/farmacocinética , Carboplatina/uso terapêutico , Compostos Organoplatínicos/farmacocinética , Compostos Organoplatínicos/uso terapêutico , Imidazolidinas/farmacocinética , Imidazolidinas/uso terapêutico , Neoplasias/terapia
20.
Eur J Clin Nutr ; 68(8): 876-81, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24781692

RESUMO

BACKGROUND/OBJECTIVES: Low birth weight (LBW) and rapid postnatal weight gain are associated with future high body adiposity; however, the cumulative effect of LBW and postnatal weight gain remains unclear. The aim of this study was to investigate the influence of body proportionality of LBW infants and postnatal weight gain on body mass index (BMI) and waist circumference (WC) of 8-year-old children. SUBJECTS/METHODS: A nested cross-sectional study was conducted in a cohort of children followed from birth to 6 months and reassessed at 8 years of age. The sample consisted of 167 children born at full term (67 with LBW and 100 with appropriate birth weight). Stunted LBW was defined as length <-2 z-score and wasted LBW as length ⩾ -2 z- score and Ponderal Index <2.5. Rapid growth was defined as weight gain greater than 0.67 s.d. score from birth to 6 months. Multivariate linear regression analysis was used to investigate the net effect of LBW and postnatal weight gain on BMI and WC, controlled for sex, total breastfeeding, socioeconomic status and maternal nutrition. RESULTS: The stunted and wasted LBW contributed significantly to the reduction of BMI and WC, and together explained 10% of the variation of these measurements. Rapid weight gain in the first 6 months of life, shorter total breastfeeding duration, higher socioeconomic status and maternal BMI significantly explained the increase in child BMI and WC. CONCLUSIONS: It was concluded that LBW led to lower body measurements, whereas rapid postnatal weight gain determined higher BMI and WC among school age children.


Assuntos
Peso ao Nascer , Estatura , Índice de Massa Corporal , Crescimento , Recém-Nascido de Baixo Peso , Circunferência da Cintura , Aumento de Peso , Antropometria , Brasil , Aleitamento Materno , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Masculino , Mães , Obesidade Infantil/etiologia , Classe Social
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