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51.
INTRODUCTION: In order to be effective, treatment for osteoporosis must be long-term. Unfortunately, according to clinical trials and clinical practice the most frequent cause of patient resignation from the treatment is adverse reactions to the medications. In the case of bisphosphonates they are most frequently connected with irritant impact of the drug on gastrointestinal mucosa. The aim of our study was to answer the question whether alendronate tablets coated with a thin neutral layer may protect gastrointestinal mucosa from the irritant effects of the active substance. MATERIAL AND METHODS: Three types of tablets were administered into the cheek pouches of 18 Syrian hamsters (divided into 3 experimental groups: I, II, III) i.e. regular alendronate tablets, coated alendronate tablets and placebo. The tablets were applied for 4 minutes a day on 4 consecutive days. 24 hours after the last application, the animals were sacrificed and segments of buccal tissue were taken for histopathological examination. Oral tissue reaction was assessed using the microscopic examination grading system developed by ISO. The following adverse changes of the tissue were recorded: epithelial lesions, leucocyte infiltration, vascular congestion and oedema. Later the irritation index was calculated. RESULTS: The irritation index was 11.0 (moderately irritant), 0.0 and 0.0 (none-irritant), in each group respectively. CONCLUSION: It appears that the administration of the coated alendronate tablets reduces the frequency and intensity of the local adverse events from the gastrointestinal tract. 相似文献
52.
Oliveira Willams Silva Jéssica Luiza S. Cruz-Neto Oswaldo Oliveira Marcela Tomaz P. Fernandes de Albuquerque Isabelle Borges Laís Angélica Lopes Ariadna Valentina 《Journal of plant research》2022,135(2):235-245
Journal of Plant Research - In mixed-ploidy populations, newly formed polyploids initially occur at low frequencies when compared to diploids. However, polyploidy may lead to morphological and... 相似文献
53.
Dorota?Gurda Luiza?Handschuh Weronika?Kotkowiak Hieronim?JakubowskiEmail author 《Amino acids》2015,47(7):1319-1339
Genetic or nutritional deficiencies in homocysteine (Hcy) metabolism lead to hyperhomocysteinemia (HHcy) and cause endothelial dysfunction, a hallmark of atherosclerosis. In addition to Hcy, related metabolites accumulate in HHcy but their role in endothelial dysfunction is unknown. Here, we examine how Hcy-thiolactone, N-Hcy-protein, and Hcy affect gene expression and molecular pathways in human umbilical vein endothelial cells. We used microarray technology, real-time quantitative polymerase chain reaction, and bioinformatic analysis with PANTHER, DAVID, and Ingenuity Pathway Analysis (IPA) resources. We identified 47, 113, and 30 mRNAs regulated by N-Hcy-protein, Hcy-thiolactone, and Hcy, respectively, and found that each metabolite induced a unique pattern of gene expression. Top molecular pathways affected by Hcy-thiolactone were chromatin organization, one-carbon metabolism, and lipid-related processes [?log(P value) = 20–31]. Top pathways affected by N-Hcy-protein and Hcy were blood coagulation, sulfur amino acid metabolism, and lipid metabolism [?log(P value)] = 4–11; also affected by Hcy-thiolactone, [?log(P value) = 8–14]. Top disease related to Hcy-thiolactone, N-Hcy-protein, and Hcy was ‘atherosclerosis, coronary heart disease’ [?log(P value) = 9–16]. Top-scored biological networks affected by Hcy-thiolactone (score = 34–40) were cardiovascular disease and function; those affected by N-Hcy-protein (score = 24–35) were ‘small molecule biochemistry, neurological disease,’ and ‘cardiovascular system development and function’; and those affected by Hcy (score = 25–37) were ‘amino acid metabolism, lipid metabolism,’ ‘cellular movement, and cardiovascular and nervous system development and function.’ These results indicate that each Hcy metabolite uniquely modulates gene expression in pathways important for vascular homeostasis and identify new genes and pathways that are linked to HHcy-induced endothelial dysfunction and vascular disease. 相似文献
54.
Conformational and biological properties of Bauhinia bauhinioides kallikrein inhibitor fragments with bradykinin‐like activities 下载免费PDF全文
Flávio Lopes Alves Maria Luiza Vilela Oliva Antonio Miranda 《Journal of peptide science》2015,21(6):495-500
Proteinase inhibitors extracted form medicinal plants are an interesting source of new drugs. Modifications in the structure of some of this kind of macromolecules could also lead to compounds of interesting biological properties. In this work, we synthesized and tested one fragment containing the reactive site of the Bauhinia bauhinioides kallikrein inhibitor (BbKI), denoted BbKI51–62, and a related analog (P2) in which a proline residue was inserted in order to mimic the N‐terminal region of the bradykinin molecule. The related retro‐inverso counterparts Ri‐BbKI51–62 and Ri‐P2 were also included. The ability of these peptides to induce contraction of stomach fundus isolated from mouse was evaluated as well as their capability to induce calcium release from a cell culture of smooth muscle from guinea pig ileum. The conformational properties of the peptides were evaluated by circular dichroism and their resistance to enzymatic degradation by exposure to human blood plasma. Our results show that neither the parent BbKI51–62 nor its Ri‐BbKI51–62 analog exhibit bradykinin‐like activity, although the retro‐inverso isomer was resistant to blood plasma degradation. On the other hand, the peptides P2 and Ri‐P2 presented contractile activities on gastric smooth muscle from stomach fundus possibly by acting via B‐2 receptor. Both compounds also induce calcium release from guinea pig ileum muscle cells in a manner similar to bradykinin. Moreover, both compounds also inhibited porcine pancreatic kallikrein. However, conformational analysis did not reveal any direct correlation between structure and biological effects. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
55.
56.
Fernanda Errero Porto Ana Luiza de Brito Portela-Castro Isabel Cristina Martins-Santos 《Ichthyological Research》2011,58(3):225-231
Cytogenetic analysis in three Rineloricaria pentamaculata populations revealed diploid number 2n = 56 chromosomes, karyotype formula 8m/sm + 48st/a and FN = 64. Owing to the presence of the heteromorphic chromosome pair
with a big submetacentric chromosome and a small acrocentric one in both males and females, 42.9% of specimens in the Tauá
Stream population had the karyotype formula 9m/sm + 47st/a and FN = 65. Analysis of the nucleolus-organizing region by Ag-NOR
and FISH techniques showed a single NOR system at pair 5 for R. pentamaculata populations of the Keller River and the Tauá Stream. However, specimens of populations of the Tatupeba Stream had multiple
NOR systems at pairs 5 and 8. A constitutive heterochromatin pattern in R. pentamaculata is mainly distributed in the pericentromeric and telomeric regions with interstitial markers in certain chromosomes. Heterochromatin
is located in the telomeric and centromeric positions of the acrocentric chromosome in the heteromorphic pair of the Tauá
Stream population. In the submetacentric chromosome the markings are located in the telomeric (short arm), pericentomeric
and interstitial (long arm) positions. The origins of polymorphisms are discussed. 相似文献
57.
Summary In contrast to the situation found in two classes of warm-blooded vertebrates, mammals and birds, the class Reptilia is not uniform with regard to total genetic content; rather, it contains two distinct categories. The close cytological kinship between snakes and birds was revealed. Both are almost identical in total genetic content, which is about 50 per cent that of placental mammals. Both have microchromosomes, as well as Z-chromosomes very similar in absolute size, comprising nearly 10 per cent of the homogametic haploid (AZ) set. This leads to the implication that snakes and birds originated from the same lineage, and that their Z-chromosomes have not changed substantially since the Jurassic period of the Mesozoic era, about 180 million years ago.Within the reptilian suborder Serpentes, the step-by-step differentiation from the primitive ZW pair to the grossly heteromorphic ZW pair could be observed. In the ancient family Boidae, the sex chromosomes were still homomorphic to each other. In the family Colubridae, the beginning of heteromorphism was manifested in two ways. In some species, a pericentric inversion on the W caused it to differ from the Z; in others, duplication of the W occurred. In the family Crotalidae, the W had apparently achieved its very specialized status; it was a distinctly smaller element.In Säo Paulo, this work was supported by Fundacão de Amparo a Pesquisa do Estado de São Paulo e Fundo de Pesquisas do Instituto Butantan. In Duarte, this work was supported in part by grant CA-05138-05, National Cancer Institute, U. S. Public Health Service. Contribution No. 36-64, Department of Biology, City of Hope Medical Center. 相似文献
58.
Bruno AN Pochmann D Ricachenevsky FK Fontella FU Bonan CD Dalmaz C Barreto-Chaves ML Sarkis JJ 《Neurochemical research》2005,30(9):1155-1161
Purinergic system exerts a significant influence on the modulation of pain pathways at the spinal site. Adenosine has antinociceptive
properties in experimental and clinical situations, while ATP exerts pronociceptive actions in different pain models. In this
study we investigated the hydrolysis of ATP to adenosine in synaptosomes from spinal cord in parallel with the nociceptive
response of rats at different ages after hypothyroidism induction. Hypothyroidism elicited a significant increase in AMP hydrolysis
to adenosine in synaptosomes from spinal cord of rats subjected to neonatal hypothyroidism and in 420-day-old rats submitted
to thyroidectomy. Accordingly, these rats presented an analgesic response as a consequence of hypothyroidism. In contrast,
the ATP hydrolysis was decreased in the spinal cord of 60-day-old hypothyroid rats in parallel with a significant increase
in nociceptive response. These results indicate the involvement of adenine nucleotides in the control of the hypothyroidism-induced
nociceptive response during development. 相似文献
59.
The Caí River (Rio Grande do Sul, Brazil) is an important watercourse that receives large amounts of industrial and untreated municipal discharges in its lower course. We employed the SMART in Drosophila melanogaster to evaluate the genotoxicity of surface waters collected from Caí sites receiving direct sewage discharge: from Montenegro (Km 52) and from S?o Sebasti?o do Caí (Km 78 and 80), and from two sites under the industrial influence (Km 13.6 and 18.6). The genotoxic analysis included three collections: March, June and September 1999, which were tested at crude sample and at 50 and 25% concentrations. Considering the industrial samples from Km 18.6 and 13.6, collected in March, June and September 1999, they were characterized as not having genetic toxicity. The urban samples collected in March--Km 52, 78 and 80--showed a significant increment in the frequencies of total spots. In Km 52 and 78 the genotoxic effect was associated to both mutational and recombinational events, although for Km 80 the increases observed were mainly related to the occurrence of homologous recombination. Moreover, the Km 80 crude sample from June and all the concentrations analyzed for Km 52 in September were also able to induce mitotic recombination. These effects were only observed in the ST cross, demonstrating the genotoxins present in the urban discharges act by direct interaction with the DNA of the somatic cells. The SMART in D. melanogaster was shown to be highly sensitive to detect genotoxic agents present in the aquatic environment, and must be better exploited for monitoring areas under anthropogenic discharges. 相似文献
60.
Fonseca SG Moins-Teisserenc H Clave E Ianni B Nunes VL Mady C Iwai LK Sette A Sidney J Marin ML Goldberg AC Guilherme L Charron D Toubert A Kalil J Cunha-Neto E 《Microbes and infection / Institut Pasteur》2005,7(4):688-697
Chronic Chagas disease occurs in 16 million individuals chronically infected by the protozoan Trypanosoma cruzi in Latin America, and may lead to a dilated cardiomyopathy in 10-30% of patients. A vigorous cellular immune response holds parasitism in check. However, up to now, few T. cruzi proteins have been shown to be recognized by CD8+ T cells from Chagas disease patients. In this study, we designed 94 peptides derived from T. cruzi proteins cruzipain and FL-160, predicted to bind to HLA-A2 molcules. After in vitro binding assays to HLA-A*0201, 26 peptides were selected, and their recognition by PBMC from Chagas disease patients was tested with the IFN-gamma ELISPOT assay. All 26 peptides were recognized by PBMC from at least one patient. Furthermore, a tetrameric HLA-A*0201 complex built with the cruzipain 60-68 peptide that was frequently recognized in the periphery also bound to CD8+ T cells from a heart-infiltrating T cell line obtained from a single patient with Chagas disease cardiomyopathy. Thus, our results suggest that the recognition of CD8+ T cell epitopes in cruzipain and FL-160 may have a pathogenic or protective role in chronic Chagas disease. 相似文献