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51.
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Thaiz Ferraz Borin Ayumi Aurea Miyakawa Leandro Cardoso Luciano de Figueiredo Borges Giovana Aparecida Gonçalves Jose Eduardo Krieger 《International journal of experimental pathology》2009,90(3):328-337
Neo-intima development and atherosclerosis limit long-term vein graft use for revascularization of ischaemic tissues. Using a rat model, which is technically less challenging than smaller rodents, we provide evidence that the temporal morphological, cellular, and key molecular events during vein arterialization resemble the human vein graft adaptation. Right jugular vein was surgically connected to carotid artery and observed up to 90 days. Morphometry demonstrated gradual thickening of the medial layer and important formation of neo-intima with deposition of smooth muscle cells (SMC) in the subendothelial layer from day 7 onwards. Transmission electron microscopy showed that SMCs switch from the contractile to synthetic phenotype on day 3 and new elastic lamellae formation occurs from day 7 onwards. Apoptosis markedly increased on day 1, while α-actin immunostaining for SMC almost disappeared by day 3. On day 7, cell proliferation reached the highest level and cellular density gradually increased until day 90. The relative magnitude of cellular changes was higher in the intima vs . the media layer (100 vs . 2 times respectively). Cyclin-dependent kinase inhibitors (CDKIs) p27Kip1 and p16INKA remained unchanged, whereas p21Cip1 was gradually downregulated, reaching the lowest levels by day 7 until day 90. Taken together, these data indicate for the first time that p21Cip1 is the main CDKI protein modulated during the arterialization process the rat model of vein arterialization that may be useful to identify and validate new targets and interventions to improve the long-term patency of vein grafts. 相似文献
53.
Edna Aparecida Ferraz de Araújo Navas Aline Cássia Inocêncio Janete Dias Almeida Graziella Nuernberg Back-Brito Adolfo José Mota Antonio Olavo Cardoso Jorge Silvia Maria Rodrigues Querido Ivan Balducci Cristiane Yumi Koga-Ito 《Journal of oral pathology & medicine》2009,38(10):764-767
Objective: The aim of this study was to evaluate the prevalence of Candida spp. and presence of oral lesions in Brazilian leprosy patients under multidrug therapy (MDT).
Methods: Thirty-eight individuals (18 males and 20 females, median age 53 years) clinically and microbiologically diagnosed as leprosy (lepromatous variant), and under MDT for at least 45 days were studied. The control group constituted by 38 healthy individuals (median age 53.5), matched to the test group in relation to age, gender and oral conditions. Oral rinses were collected and the Candida identification was performed by phenotypic tests. The existence of Candida dubliniensis among the isolates was analyzed using a validated multiplex PCR assay. Twenty-nine leprosy patients were examined intra-orally for the presence of lesions. Data were analyzed by z- and Mann–Whitney tests (α = 5%).
Results: Yeast carriage rate between leprosy patients (65.8%) and controls (47.4%) was similar ( P = 0.099), and no significant difference between yeast counts was observed ( P = 0.1004). Candida albicans was the most frequently isolated species in both groups. In the leprosy group, Candida tropicalis and Candida parapsilosis were also identified. In the control group, we additionally identified Candida tropicalis , Candida glabrata and Candida kefyr. Candida dubliniensis was not detected. No leprosy-related oral lesion was registered.
Conclusion: Within the limits of the study, we concluded that Brazilian leprosy patients under MDT showed similar levels of carriage and Candida species distribution in relation to the controls. 相似文献
Methods: Thirty-eight individuals (18 males and 20 females, median age 53 years) clinically and microbiologically diagnosed as leprosy (lepromatous variant), and under MDT for at least 45 days were studied. The control group constituted by 38 healthy individuals (median age 53.5), matched to the test group in relation to age, gender and oral conditions. Oral rinses were collected and the Candida identification was performed by phenotypic tests. The existence of Candida dubliniensis among the isolates was analyzed using a validated multiplex PCR assay. Twenty-nine leprosy patients were examined intra-orally for the presence of lesions. Data were analyzed by z- and Mann–Whitney tests (α = 5%).
Results: Yeast carriage rate between leprosy patients (65.8%) and controls (47.4%) was similar ( P = 0.099), and no significant difference between yeast counts was observed ( P = 0.1004). Candida albicans was the most frequently isolated species in both groups. In the leprosy group, Candida tropicalis and Candida parapsilosis were also identified. In the control group, we additionally identified Candida tropicalis , Candida glabrata and Candida kefyr. Candida dubliniensis was not detected. No leprosy-related oral lesion was registered.
Conclusion: Within the limits of the study, we concluded that Brazilian leprosy patients under MDT showed similar levels of carriage and Candida species distribution in relation to the controls. 相似文献
54.
Breno Rates Karla K.F. Ferraz Márcia H. Borges Maria Elena De Lima Adriano M.C. Pimenta 《Toxicon》2008,52(5):611-618
MALDI-TOF-TOF and de novo sequencing were employed to assess the Tityus serrulatus venom peptide diversity. Previous works has shown the cornucopia of molecular masses, ranging from 800 to 3000 Da, present in the venom from this and other scorpions species. This work reports the identification/sequencing of several of these peptides. The majority of the peptides found were fragments of larger venom toxins. For instance, 28 peptides could be identified as fragments from Pape proteins, 10 peptides corresponded to N-terminal fragments of the TsKβ (scorpine-like) toxin and fragments of potassium channel toxins (other than the k-beta) were sequenced as well. N-terminal fragments from the T. serrulatus hypotensins-I and II and a novel hypotensin-like peptide could also be found. This work also reports the sequencing of novel peptides without sequence similarities to other known molecules. 相似文献
55.
56.
Ferraz AC Xavier LL Hernandes S Sulzbach M Viola GG Anselmo-Franci JA Achaval M Da Cunha C 《Brain research》2003,986(1-2):200-205
The immunostaining for tyrosine hydroxylase (TH) in the substantia nigra pars compacta (SNpc) and in the ventral tegmental area (VTA) after intranigral infusion of 6-hydroxydopamine (6-OHDA, 6 microg/side) was analyzed in ovariectomized adult female Wistar rats. Estrogen replacement for 52 days (400-microg 17-beta-estradiol capsules) did not prevent the loss of TH-immunoreactive cells induced by 6-OHDA in the SNpc. This result indicates that the neuroprotective effect of dopaminergic mesencephalic cells is not observed with long-term estrogen replacement. 相似文献
57.
Ferraz G Russell GJ Stouffer PC Bierregaard RO Pimm SL Lovejoy TE 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(24):14069-14073
In the face of worldwide habitat fragmentation, managers need to devise a time frame for action. We ask how fast do understory bird species disappear from experimentally isolated plots in the Biological Dynamics of Forest Fragments Project, central Amazon, Brazil. Our data consist of mist-net records obtained over a period of 13 years in 11 sites of 1, 10, and 100 hectares. The numbers of captures per species per unit time, analyzed under different simplifying assumptions, reveal a set of species-loss curves. From those declining numbers, we derive a scaling rule for the time it takes to lose half the species in a fragment as a function of its area. A 10-fold decrease in the rate of species loss requires a 1,000-fold increase in area. Fragments of 100 hectares lose one half of their species in <15 years, too short a time for implementing conservation measures. 相似文献
58.
Pinheiro ET Gomes BP Ferraz CC Teixeira FB Zaia AA Souza Filho FJ 《Oral microbiology and immunology》2003,18(2):100-103
Studies of the microbiota from the canals of teeth with failure of endodontic therapy have revealed that it differs markedly from that of untreated necrotic dental pulps. This study aimed to evaluate the microbiota of 30 root-filled teeth with persisting periapical lesions and to test the antibiotic susceptibility of the most prevalent species. Microbial samples, isolation and speciation were done using advanced microbiologic techniques for anaerobic species. A total of 55 bacterial species were isolated, 80% were gram-positives and 58% facultative anaerobic microorganisms. The bacterial genera most frequently recovered were Enterococcus, Streptococcus, Peptostreptococcus and Actinomyces. Antibiotic sensitivity of Enterococcus faecalis and Peptostreptococcus spp. was accomplished with the E-test system. All species studied were susceptible to benzylpenicillin, amoxicillin, amoxicillin combined with clavulanate. However, 20% of the E.faecalis strains were resistant to erythromycin and 60% to azithromycin. It was concluded that microbial flora in canals after endodontic failure comprised predominantly facultative anaerobes and gram-positive species. E.faecalis was the species most frequently isolated and showed erythromycin and azithromycin resistance among the isolates. 相似文献
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60.
This work synthesizes the authors' views on the damages to the development of human capital in health services, which are caused by the disregard to the human spiritual dimension. New administration paradigms related to the development of spirituality are pointed out. Considering that the spiritual dimension has a systemic nature and that, by means of ethics and esthetics, it harmonizes all of man's dimensions in his relationships with others, the authors aim at approaching the spiritual value as fundamental for the re-humanization of the managing nurse's job. They recommend the integration of the spiritual dimension to the daily work of such professional as a determinant factor for a new performance as well as an inductor for nurses' better personal and professional life quality. 相似文献