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21.
The fig (Ficus L.) infructescence, called syconium, is a receptacle with an apical opening, the ostiole, closed by bracts. The ostiolar bracts produce an exudate, which is rather conspicuous in some species. It has not been histochemically analyzed yet, and the structures responsible for its production are still unknown. Some wild growing species of Ficus from Brazil produce high amounts of this ostiolar exudate. Ficus enormis (Mart. ex Miq.) Miq. grows as trees or shrubs in the Atlantic rainforest. Our goal was to identify the secretory structures present in the inflorescence and, to characterize histochemically the ostiolar tissues and exudates. Syconia samples of F. enormis were processed and stained according to the usual techniques in plant anatomy. The morphological analysis revealed different types of bracts, one type specialized in secretion, another showing transitional characteristics between secretory and non-secreting bracts, and a third one being non-secreting. They are designated as secretory ostiolar bracts, transitional bracts and wall bracts. The floral bracteoles, digital-shaped colleters present in the ostiole, at the syconium axis and at the flower receptacle, were also analyzed. All have similar structure, like finger-shaped secretory trichomes. The colleters present among ostiolar bracts may contribute to production and composition of the ostiole exudate. 相似文献
22.
Li Ping Chung Svetlana Baltic Manuel Ferreira Suzanna Temple Grant Waterer Philip J. Thompson 《PloS one》2014,9(4)
Background
β2 adrenergic receptor (ADRβ2) polymorphisms including ADRβ2+46G>A have been reported to cause adverse outcomes in mild asthmatics. The extent to which ADRβ2 polymorphisms and in particular their haplotypes contribute to severe asthma is unknown.Objective
To determine the association of ADRβ2 polymorphisms and haplotypes with asthma severity.Methods
Caucasians (n = 2979) were genotyped for 11 ADRβ2 polymorphisms. The cohort (mean age 39.6, 60% female) included 2296 non-asthmatics, 386 mild asthmatics, 172 moderate asthmatics and 125 severe asthmatics. Haplotype frequency and haplotype pair for each subject was determined using the PHASE algorithm.Results
The three asthmatic cohorts were comparable in age and gender but were distinguishable from each other in terms of symptoms, spirometry, medication use and health care utilisation (p <0.001). None of the polymorphisms showed a genotypic or allelic association with asthma diagnosis or severity. Nine haplotypes were identified and no association was found with asthma diagnosis or severity per se. Haplotype pair 2/4 was associated with asthma severity (Trend Test, OR 1.42, p = 0.0008) but not with asthma per se. Prevalence of haplotype pair 2/2 appeared to decrease with asthma severity (Trend Test, OR 0.78, p = 0.067). Two new haplotypes were identified, occurring exclusively in asthmatics at a frequency of ≥ 1%. In addition, a positive association between carriage of ADRβ2 +523*C and increased risk of atopy was discovered.Conclusions
ADRβ2 haplotype pair 2/4 is associated with severe asthma and is consistent with findings of poor bronchodilator response in mild asthmatics who are also haplotype 2/4. 相似文献23.
F. Moscoso L. Ferreira F. J. Deive P. Morán M. A. Sanromán 《Bioprocess and biosystems engineering》2013,36(2):133-141
In the present work, biodegradation of phenanthrene by a bacterial consortium (LB2), isolated from lab-polluted soils has been investigated. The 16S rRNA gene-based molecular analysis revealed that the bacterial consortium LB2 consisted of two strains showing a very high homology with Staphylococcus warneri and Bacillus pumilus. The optimization of phenanthrene degradation by the consortium LB2, using a central composite face-centered design was carried out taking into account three important parameters such as temperature, pH, and phenanthrene concentration. Near complete phenanthrene degradation was reached by consortium LB2 at the optimal conditions (pH of 7.5 and 37.5 °C) in less than 48 h. Moreover, the efficiency of phenanthrene biodegradation was assessed by using logistic and Luedeking and Piret-type models. Finally, the process was implemented at bench-scale bioreactor and the main degradation routes were identified based on GC-MS data. 相似文献
24.
Rodini CO Batista AC Dionísio TJ Santos CF Cunha FQ Lara VS 《Journal of molecular histology》2008,39(3):275-282
The immunopathologic and inflammatory mechanisms involved in periodontal disease (PD) include the participation of host resident,
inflammatory cells and chemical mediators. Metalloproteinases (MMPs) and nitric oxide (NO) play essential role in extracellular
matrix turnover of periodontal tissue destruction. In this study, by means of RT-PCR through semi-quantitative densitometric
scanning methods, the expression of MMPs -2 and -9 and inducible NO synthase (iNOS) was temporally and spatially investigated
during the destructive mechanisms of experimentally induced PD in rats. Samples from different periods were microscopically
analyzed and compared with the contralateral side (control). Our results showed significant expression of MMP-9 and iNOS in
tissues affected by PD, as compared with controls, three days after PD induction, simultaneously with the beginning of alveolar
bone loss. At 7 days post induction, only the MMP-9 mRNA presented a significantly higher expression, as compared with the
respective controls. Thus, in the rat ligature-induced PD, MMP-9 and iNOS might importantly participate in the early stages
of the disease, including inflammatory cell migration, tissue destruction and alveolar bone resorption. Also, we may suggest
that the exuberant presence of PMNs may be related to the important expression of iNOS and MMP-9 found at 3 days post induction. 相似文献
25.
Leonardo F Ferreira Shunsaku Koga Thomas J Barstow 《Journal of applied physiology》2007,103(6):1999-2004
Utilization of near-infrared spectroscopy (NIRS) in clinical exercise testing to detect microvascular abnormalities requires characterization of the responses in healthy individuals and theoretical foundation for data interpretation. We examined the profile of the deoxygenated hemoglobin signal from NIRS {deoxygenated hemoglobin + myoglobin [deoxy-(Hb+Mb)] approximately O(2) extraction} during ramp exercise to test the hypothesis that the increase in estimated O(2) extraction would be close to hyperbolic, reflecting a linear relationship between muscle blood flow (Q(m)) and muscle oxygen uptake (Vo(2)(m)) with a positive Q(m) intercept. Fifteen subjects (age 24 +/- 5 yr) performed incremental ramp exercise to fatigue (15-35 W/min). The deoxy-(Hb+Mb) response, measured by NIRS, was fitted by a hyperbolic function [f(x) = ax/(b + x), where a is the asymptotic value and b is the x value that yields 50% of the total amplitude] and sigmoidal function {f(x) = f(0) + A/[1 + e(-(-c+dx))], where f(0) is baseline, A is total amplitude, and c is a constant dependent on d, the slope of the sigmoid}, and the goodness of fit was determined by F test. Only one subject demonstrated a hyperbolic increase in deoxy-(Hb+Mb) (a = 170%, b = 193 W), whereas 14 subjects displayed a sigmoidal increase in deoxy-(Hb+Mb) (f(0) = -7 +/- 7%, A = 118 +/- 16%, c = 3.25 +/- 1.14, and d = 0.03 +/- 0.01). Computer simulations revealed that sigmoidal increases in deoxy-(Hb+Mb) reflect a nonlinear relationship between microvascular Q(m) and Vo(2)(m) during incremental ramp exercise. The mechanistic implications of our findings are that, in most healthy subjects, Q(m) increased at a faster rate than Vo(2)(m) early in the exercise test and slowed progressively as maximal work rate was approached. 相似文献
26.
Luciana da Silva Ruiz Sonia Khouri Rosane Christine Hahn Eriques Gonçalves da Silva Vanessa Krummer Perinazzo de Oliveira Rinaldo Ferreira Gandra Claudete Rodrigues Paula 《Mycopathologia》2013,175(3-4):231-239
Opportunistic infections are an increasingly common problem in hospitals, and the yeast Candida parapsilosis has emerged as an important nosocomial pathogen. The aims of this study were to determine and compare (i) the prevalence rate among C. parapsilosis complex organisms isolated from blood in a public children’s hospital in São Paulo state, (ii) the ability of the complex C. parapsilosis species identified to produce biofilm and (iii) the antifungal susceptibility profiles. Forty-nine (49) specimens of isolated blood yeast were analyzed, previously identified as C. parapsilosis by conventional methods. After the molecular analysis, the isolates were characterized as C. parapsilosis sensu stricto (83.7 %), C. orthopsilosis (10.2 %) and C. metapsilosis (6.1 %). All species were able to form biofilm. The species with the highest biofilm production was C. parapsilosis sensu stricto, followed by C. orthopsilosis and further by C. metapsilosis. All of the strains have demonstrated similar susceptibility to fluconazole, caspofungin, voriconazole, cetoconazole and 5-flucytosine. Only one strain of C. parapsilosis was resistant to amphotericin B. Regarding itraconazole, 66.6 and 43.9 % isolates of C. metapsilosis and C. parapsilosis, respectively, have demonstrated to be susceptible dose-dependent, with one isolate of the latter species resistant to the drug. Candida parapsilosis sensu stricto has demonstrated to be the less susceptible, mainly to amphotericin B, caspofungin and “azoles” such as fluconazole. Therefore, C. metapsilosis and C. orthopsilosis are still involved in a restricted number of infections, but these data have become essential for there are very few studies of these species in Latin America. 相似文献
27.
An Evaluation of Habitat Rehabilitation on Coastal Dune Forests in Northern KwaZulu-Natal, South Africa 总被引:5,自引:0,他引:5
R. J. van Aarde S. M. Ferreira J. J. Kritzinger P. J. van Dyk M. Vogt T. D. Wassenaar 《Restoration Ecology》1996,4(4):334-345
The rehabilitation program conducted by Richards Bay Minerals (RBM) of areas exposed to opencast surface mining of sand dunes north of Richards Bay (28°43'S, 32°12'E) on the coast of northern KwaZulu-Natal Province commenced 16 years before this study and has resulted in the development of a series of known-aged stands of vegetation. By assuming that these spatially separated stands develop along a similar pathway over time, instantaneous sampling should reveal successional or other changes usually associated with aging and should provide an opportunity to evaluate the success of rehabilitation. We compare relative densities of pioneer and secondary species, species richness, and a similarity index of the herbaceous layer, tree, beetle, millipede, bird, and small-mammal communities of rehabilitating areas of known age with those of 30-year-old unmined forests and unmined forests of unknown age adjacent to the rehabilitating area. Species richness for all but the mammalian taxa increased with increasing age of rehabilitating stands. For all taxa but the mammals and herbaceous layer, the unmined stands harbored more species than the mined rehabilitating stands. The relative densities of pioneer species of all the taxa decreased with an increase in the age of rehabilitating stands, whereas those of the secondary species increased with an increase in habitat age. Similarity between unmined stands and rehabilitating stands of different ages increased with increasing regeneration age of rehabilitating stands, suggesting that rehabilitating communities, in terms of species composition and relative densities, are developing towards the status of unmined communities. Rehabilitation based on RBM's management program of limited interference is occurring and may result in the reestablishment of a coastal dune forest ecosystem. But rehabilitation resulting from succession depends on the availability of species sources from which colonization can take place. In the Richards Bay mining operation the present mining path is laid out so that such refuges are present. 相似文献
28.
Patricia Fagundes Costa Geisa Ferreira Fernandes Priscila Oliveira dos Santos Cristiane Candida Amaral Zoilo Pires Camargo 《Mycopathologia》2010,169(1):37-46
The ecological niche or exact habitat of the fungus Paracoccidioides brasiliensis is not known, and few isolates have been obtained from the environment. In this study, ten isolates were analyzed with respect
to antigenic composition, serology, pathogenicity, and molecular aspects. Gp43 is considered to be the molecular basis for
the serodiagnosis of paracoccidioidomycosis; however, in this study only six of the environmental isolates secreted this molecule
(four in great amounts and two in small amounts). Other molecules were also produced. When exoantigens from these isolates
were tested using immunodiffusion, only four preparations were positive by ID tests. However, when these exoantigens were
tested by ELISA, all of them except one were able to detect anti-P. brasiliensis antibodies. In Western blot assays, these exoantigens showed different reactivities. Isolates that secreted gp43 presented
positive reactions for this molecule, and isolates that did not secrete gp43 gave positive reactions for other minor molecules.
RAPD analysis revealed that there is great genetic variation between these environmental isolates. These isolates were non-pathogenic:
no mortality was observed among the inoculated mice during an 18-month follow-up period. 相似文献
29.
Carlota Pascoal Sandra Brasil Rita Francisco Dorinda Marques-da-Silva Agnes Rafalko Jaak Jaeken Paula A. Videira Luísa Barros Vanessa dos Reis Ferreira 《Orphanet journal of rare diseases》2018,13(1):215
Background
Health-related Quality of Life (HrQoL) is a multidimensional measure, which has gained clinical and social relevance. Implementation of a patient-centred approach to both clinical research and care settings, has increased the recognition of patient and/or observer reported outcome measures (PROMs or ObsROMs) as informative and reliable tools for HrQoL assessment. Inherited Metabolic Diseases (IMDs) are a group of heterogeneous conditions with phenotypes ranging from mild to severe and mostly lacking effective therapies. Consequently, HrQoL evaluation is particularly relevant.Objectives
We aimed to: (1) identify patient and/or caregiver-reported HrQoL instruments used among IMDs; (2) identify the main results of the application of each HrQoL tool and (3) evaluate the main limitations of HrQoL instruments and study design/methodology in IMDs.Methods
A scoping review was conducted using methods outlined by Arksey and O’Malley. Additionally, we critically analysed each article to identify the HrQoL study drawbacks.Results
Of the 1954 studies identified, 131 addressed HrQoL of IMDs patients using PROMs and/or ObsROMs, both in observational or interventional studies. In total, we identified 32 HrQoL instruments destined to self- or proxy-completion; only 2% were disease-specific. Multiple tools (both generic and disease-specific) proved to be responsive to changes in HrQoL; the SF-36 and PedsQL questionnaires were the most frequently used in the adult and pediatric populations, respectively. Furthermore, proxy data often demonstrated to be a reliable approach complementing self-reported HrQoL scores. Nevertheless, numerous limitations were identified especially due to the rarity of these conditions.Conclusions
HrQoL is still not frequently assessed in IMDs. However, our results show successful examples of the use of patient-reported HrQoL instruments in this field. The importance of HrQoL measurement for clinical research and therapy development, incites to further research in HrQoL PROMs’ and ObsROMs’ creation and validation in IMDs.30.
Rosete Pescador Gilberto Barbante Kerbauy Wagner de Melo Ferreira Eduardo Purgatto Rogério Mamoru Suzuki Miguel Pedro Guerra 《Plant Growth Regulation》2012,68(1):67-76
Endogenous levels of IAA, ABA and four types of CKs were analyzed in zygotic and indirect (ISE) and direct somatic embryogenesis of Acca sellowiana. Zygotic and somatic embryos at different developmental stages were sampled for morphological and hormonal analysis. Both embryo types showed substantial asymmetry in hormone levels. Zygotic embryos displayed a conspicuous peak of IAA in early developmental stages. The results outlined the hormonal variations occurring during zygotic and somatic embryogenesis regarding the timing, nature and hormonal status involved in both processes. The short transient pulse of IAA observed on the 3rd day in culture was suggested to be involved with the signaling for the induction of somatic embryogenesis. Fertilized ovule development was associated with increased IAA levels 21?C24?days after pollination, followed by a sharp decrease in the cotyledonary stage, both in zygotic and somatic embryos. There was a prominent increase in ABA levels in cultures which generated ISE 24?C30?days after pollination, a period that corresponds to the heart and torpedo stages. The levels of total CKs (Z, [9R]Z, iP and [9R]iP) were also always higher in zygotic than in somatic embryogenesis. While zygotic embryogenesis was dominated by the presence of zeatin, the somatic process, contrarily, was characterized by a large variation of the other cytokinin forms and amounts studied. The above results, when taken together, could be related to the previously observed high frequency formation of anomalous somatic embryos formed in A. sellowiana, as well as to their low germination ability. 相似文献