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51.
This work was based on the analysis of digital images of histochemical profile from subcutaneous lesions in sporotrichosis
(ST) and chromoblastomycosis (CM) patients. An additional aim was the detection of carbohydrate expression using lectin histochemical
analysis of the different carbohydrates in the fungal cell wall from four different species (Sporothrix
schenckii, Fonsecaea pedrosoi, Phialophora verrucosa, and Cladophialophora carrionii) associated with diseases mentioned earlier. Slides from tissue biopsies from ST and CM positive patients (n = 10, each) were stained according to routine techniques. Slides were incubated with 25 μg/ml of Con A lectins and WGA conjugated
to peroxidase. Digital image analysis was carried out in a workstation using OPTIMAS™ software system. Routine histochemistry
results indicated that there is significantly higher collagen deposition and elastic fibers in ST characteristic lesions compared
with that found in CM cases. The ST interstitial fibrosis area was larger than in CM lesions. Comparative lectin binding showed
a positive and intense lectin staining pattern in the cell wall of S. schenckii, suggesting a higher expression of glucose/mannose and N-acetyl glucosamine in their cell surface as evidenced by Con A and WGA, respectively. However, these lectins were not effective
to recognize some carbohydrates moieties in the F. pedrosoi, P. verrucosa, and C. carrionii. Such findings contribute to additional information about specific recognition processes between fungal parasites and their
host cell targets may be mediated by the interaction of carbohydrate-binding proteins, such as lectins, on the surface of
one type of cell that combine with complementary sugars on the surface of another cells into fibro-connective tissues associated
with lesions. 相似文献
52.
Ana Luiza Freire Cintia Lacerda Ramos Euziclei Gonzaga de Almeida Whasley Ferreira Duarte Rosane Freitas Schwan 《World journal of microbiology & biotechnology》2014,30(2):567-577
Yakupa is a traditional non-alcoholic cassava beverage produced by Brazilian Amerindians. In this work the microbial dynamics and metabolites involved in yakupa fermentation were investigated by PCR-denaturing gradient gel electrophoresis and chromatography analysis, respectively. The lactic acid bacteria (LAB) population was higher than yeast in the beginning of fermentation (5 log CFU mL?1 and 3 log CFU mL?1, respectively) and after 36 h both population increased reaching 7 log CFU mL?1, remaining constant until 60 h. Culture dependent and independent methods in combination identified the bacteria Lactobacillus fermentum, L. plantarum, Weissela cibaria and W. confusa, and yeasts Saccharomyces cerevisiae and Pichia kudriavzevii. Maltose (41.2 g L?1), ethanol (6.5 g L?1) and lactic acid (7.8 g L?1) were the most abundant compounds identified by high performance liquid chromatography. Aldehydes, acids, alcohols and esters were identified by gas chromatography flame ionization detection. By the metabolites and PCA analysis we may assign the beverage’s flavor to the microbial metabolism. Heterolactic LAB and S. cerevisiae dominated the yakupa fermentation, being responsible for the organoleptic characteristics of the final product. This is the first time that the microbial dynamics and physicochemical parameters were investigated in the yakupa beverage and it may contribute to the future selection of starter cultures to perform yakupa fermentations. 相似文献
53.
Rita de Cássia Andrade Melo Emmily Margate Rodrigues de Barros Noel Guedes Loureiro Heloísa Ramos Lacerda de Melo Maria Amélia Vieira Maciel Ana Catarina Souza Lopes 《Current microbiology》2014,69(6):824-831
Klebsiella pneumoniae strains can produce different virulence factors, such as fimbrial adhesins and siderophores, which are important in the colonization and development of the infection. The aims of this study were to determine the occurrence of fimH, mrkD, and irp2 virulence genes in 22 KPC-2-producing K. pneumoniae isolates as well as 22 not producing-KPC isolates, from patients from different hospitals in Recife-PE, Brazil, and also to analyze the clonal relationship of the isolates by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The genes were detected by PCR and DNA sequencing. The bla KPC-2 gene was identified in 22 KPC-positive isolates. On analyzing the antimicrobial susceptibility profile of the isolates, it was detected that polymyxin and amikacin were the antimicrobials of best activity against K. pneumoniae. On the other hand, five isolates exhibited resistance to polymyxin. In the KPC-positive group, was observed a high rate of resistance to cephalosporins, followed by carbapenems. Molecular typing by ERIC-PCR detected 38 genetic profiles, demonstrating a multiclonal spread of the isolates analyzed. It was observed that the virulence genes irp2, mrkD, and fimH were seen to have together a higher frequency in the KPC-positive group. The accumulation of virulence genes of KPC-positive K. pneumoniae isolates, observed in this study, along with the multi-resistance impose significant therapeutic limitations on the treatment of infections caused by K. pneumoniae. 相似文献
54.
Ian Louis Ross Collet Dandara Marelize Swart Miguel Lacerda Desmond Schatz Dirk Jacobus Blom 《PloS one》2014,9(1)
Background
Addison’s disease (AD) has been associated with an increased risk of cardiovascular disease. Glucocorticoid receptor polymorphisms that alter glucocorticoid sensitivity may influence metabolic and cardiovascular risk factors in patients with AD. The 9β polymorphism of the glucocorticoid receptor gene is associated with relative glucocorticoid resistance and has been reported to increase the risk of myocardial infarction in the elderly. We explored the impact of this polymorphism in patients with AD.Materials and Methods
147 patients with AD and 147 age, gender and ethnicity matched healthy controls were recruited. Blood was taken in a non-fasted state for plasma lipid determination, measurement of cardiovascular risk factors and DNA extraction.Results
Genotype data for the 9β polymorphism was available for 139 patients and 146 controls. AD patients had a more atherogenic lipid profile characterized by an increase in the prevalence of small dense LDL (p = 0.003), increased triglycerides (p = 0.002), reduced HDLC (p<0.001) an elevated highly sensitive C-reactive protein (p = 0.01), compared with controls. The 9β polymorphism (at least one G allele) was found in 28% of patients and controls respectively. After adjusting for age, gender, ethnicity, BMI and hydrocortisone dose per metre square of body surface area in patients, there were no significant metabolic associations with this polymorphism and hydrocortisone doses were not higher in patients with the polymorphism.Conclusions
This study did not identify any associations between the 9β polymorphism and cardiovascular risk factors or hydrocortisone dose and determination of this polymorphism is therefore unlikely to be of clinical benefit in the management of patients with AD. 相似文献55.
Alexandre Grangeiro Maria Mercedes Escuder Alex Jones Flores Cassanote Rosa Alencar Souza Artur O. Kalichman Valdiléa Veloso Maria Letícia Rodrigues Ikeda Nêmora Tregnago Barcellos Carlos Brites Unai Tupinanbás Noaldo O. Lucena Carlos Lima da Silva Heloisa Ramos Lacerda Beatriz Grinsztejn Euclides Ayres Castilho 《PloS one》2014,9(5)
Background
The HIV-Brazil Cohort Study was established to analyze the effectiveness of combination antiretroviral therapy (cART) and the impact of this treatment on morbidity, quality of life (QOL) and mortality. The study design, patients’ profiles and characteristics of cART initiation between 2003 and 2010 were described.Methodology/Principal Findings
Since 2003, the HIV-Brazil Cohort has been following HIV-infected adults receiving cART at 26 public health care facilities, using routine clinical care data and self-reported QOL questionnaires. When not otherwise available, data are obtained from national information systems. The main outcomes of interest are diseases related or unrelated to HIV; suppression of viral replication; adverse events; virological, clinical and immunological failures; changes in the cART; and mortality. For the 5,061 patients who started cART between 2003 and 2010, the median follow-up time was 4.1 years (IQR 2.2–5.9 years) with an 83.4% retention rate. Patient profiles were characterized by a predominance of men (male/female ratio 1.7∶1), with a mean age of 36.9 years (SD 9.9 years); 55.2% had been infected with HIV via heterosexual contact. The majority of patients (53.4%) initiated cART with a CD4+ T-cell count ≤200 cells/mm3. The medications most often used in the various treatment regimens were efavirenz (59.7%) and lopinavir/ritonavir (18.2%). The proportion of individuals achieving viral suppression within the first 12 months of cART use was 77.4% (95% CI 76.1–78.6). Nearly half (45.4%) of the patients presented HIV-related clinical manifestations after starting cART, and the AIDS mortality rate was 13.9 per 1,000 person-years.Conclusions/Significance
Results from cART use in the daily practice of health services remain relatively unknown in low- and middle-income countries, and studies with the characteristics of the HIV-Brazil Cohort contribute to minimizing these shortcomings, given its scope and patient profile, which is similar to that of the AIDS epidemic in the country. 相似文献56.
Williane Fernanda Siqueira Agostinho Gonalves Viana Joo Luís Reis Cunha Leticia Mansur Rosa Lilian Lacerda Bueno Daniella Castanheira Bartholomeu Mariana Santos Cardoso Ricardo Toshio Fujiwara 《PLoS neglected tropical diseases》2021,15(9)
Visceral leishmaniasis (VL) is caused by protozoa belonging to the Leishmania donovani complex and is considered the most serious and fatal form among the different types of leishmaniasis, if not early diagnosed and treated. Among the measures of disease control stand out the management of infected dogs and the early diagnosis and appropriate treatment of human cases. Several antigens have been characterized for use in the VL diagnosis, among them are the recombinant kinesin-derived antigens from L. infantum, as rK39 and rKDDR. The main difference between these antigens is the size of the non-repetitive kinesin region and the number of repetitions of the 39 amino acid degenerate motif (6.5 and 8.5 repeats in rK39 and rKDDR, respectively). This repetitive region has a high antigenicity score. To evaluate the effect of increasing the number of repeats on diagnostic performance, we designed the rKDDR-plus antigen, containing 15.3 repeats of the 39 amino acid degenerate motif, besides the absence of the non-repetitive portion from L. infantum kinesin. Its performance was evaluated by enzyme-linked immunosorbent assay (ELISA) and rapid immunochromatographic test (ICT), and compared with the kinesin-derived antigens (rKDDR and rK39). In ELISA with human sera, all recombinant antigens had a sensitivity of 98%, whereas the specificity for rKDDR-plus, rKDDR and rK39 was 100%, 96% and 71%, respectively. When evaluated canine sera, the ELISA sensitivity was 97% for all antigens, and the specificity for rKDDR-plus, rKDDR and rK39 was 98%, 91% and 83%, respectively. Evaluation of the ICT/rKDDR-plus, using human sera, showed greater diagnostic sensitivity (90%) and specificity (100%), when compared to the IT LEISH (79% and 98%, respectively), which is based on the rK39 antigen. These results suggest that the increased presence of repetitive motifs in the rKDDR-plus protein improves the diagnostic performance of serological tests by increasing the specificity and accuracy of the diagnosis. 相似文献
57.
Charcot-Marie-Tooth (CMT) disease is one of the most common heritable neuromuscular disorders, affecting 1 in every 2500 people. Mutations in LITAF have been shown to be causative for CMT type 1C disease. In this paper we explore the subcellular localization of wild type LITAF and mutant forms of LITAF known to cause CMT1C (T49M, A111G, G112S, T115N, W116G, L122V and P135T). The results show that LITAF mutants A111G, G112S, W116G, and T115N mislocalize from the late endosome/lysosome to the mitochondria while the mutants T49M, L122V, and P135T show partial mislocalization with a portion of the total protein present in the late endosome/lysosome and the remainder of the protein localized to the mitochondria. This suggests that different mutants of LITAF will produce differing severity of disease. We also explored the effect of the presence of mutant LITAF on wild-type LITAF localization. We showed that in cells heterozygous for LITAF, CMT1C mutants T49M and G112S are dominant since wild-type LITAF localized to the mitochondria when co-transfected with a LITAF mutant. Finally, we demonstrated how LITAF transits to the endosome and mitochondria compartments of the cell. Using Brefeldin A to block ER to Golgi transport we demonstrated that wild type LITAF traffics through the secretory pathway to the late endosome/lysosome while the LITAF mutants transit to the mitochondria independent of the secretory pathway. In addition, we demonstrated that the C-terminus of LITAF is necessary and sufficient for targeting of wild-type LITAF to the late endosome/lysosome and the mutants to the mitochondria. Together these data provide insight into how mutations in LITAF cause CMT1C disease. 相似文献
58.
Cumulative ecological effects of a Neotropical reservoir cascade across multiple assemblages 总被引:2,自引:0,他引:2
Natália Carneiro Lacerda dos Santos Emili García-Berthou Juliana Déo Dias Taise Miranda Lopes Igor de Paiva Affonso William Severi Luiz Carlos Gomes Angelo Antonio Agostinho 《Hydrobiologia》2018,806(1):77-93
Kettle holes are often abundant within agriculturally used moraine landscapes. They are highly enriched with nutrients and considered hotspots of carbon turnover. However, data on their primary productivity remain rare. We analysed two kettle holes typical to Germany with common aquatic plant communities during one year. We hypothesised that gross primary production (GPP) rates would be high compared to other temperate freshwater ecosystems, leading to high sediment deposition. Summer GPP rates (4.5–5.1 g C m?2 day?1) were higher than those of most temperate freshwater systems, but GPP rates were reduced by 90% in winter. Macrophytes dominated GPP from May to September with emergent macrophytes accounting for half of the GPP. Periphyton contributed to most of the system GPP throughout the rest of the year. Sediment deposition rates were high and correlated with GPP in one kettle hole. In contrast, due to prolonged periods of anoxia, aerobic sediment mineralisation was low while sediment phosphorus release was significant. Our results suggest that kettle holes have a high potential for carbon burial, provided they do not fully dry up during warm years. Due to their unique features, they should not be automatically grouped with ponds and shallow lakes in global carbon budget estimates. 相似文献
59.
Rosimeire Borges Moreira Lacerda Thamires Rodrigues Freitas Mário Machado Martins Thaise Lara Teixeira Cláudio Vieira da Silva Pamela Aparecida Candido Ronaldo Junio de Oliveira Claudio Viegas Júnior Vanderlan da Silva Bolzani Amanda Danuello Marcos Pivatto 《Bioorganic & medicinal chemistry》2018,26(22):5816-5823
Leishmaniasis is one of the most important neglected tropical diseases (NTDs) that are especially common among low-income populations in developing regions of Africa, Asia, and the Americas. Many natural products, particularly alkaloids, have been reported to have inhibitory activity against arginase, the key enzyme in the pathology caused by Leishmania sp. In this way, piperidine alkaloids (–)-cassine (1), (–)-spectaline (2), (–)-3-O-acetylcassine (3), and (–)-3-O-acetylspectaline (4) were isolated from Senna spectabilis flowers. These compounds (1/2 and 3/4) initially present as homologous mixtures were separated by high performance liquid chromatography and evaluated against the promastigote phase of Leishmania amazonensis. In addition, molecular docking simulations were implemented in order to probe the binding modes of the ligands 1–4 to the amino acids in the active site of L. amazonensis arginase. Alkaloid 2 (IC50 15.81?μg?mL?1) was the most effective against L. amazonensis. Compounds 2 and 4, with larger side chain, were more effective against the parasite than compounds 1 and 3. The cell viability test on Vero cells revealed that compound 2 (CC50 66.67?μg?mL?1) was the most toxic. The acetyl group in the 3-O position of the parent structures reduced the leishmanicidal activity and the toxicity of the alkaloids. Further, molecular docking suggested that Asn143 is essential for arginase to interact with (–)-spectaline-derived compounds, which agreed with the IC50 measurements. Our findings revealed that S. spectabilis is an important source of piperidine alkaloids with leishmanicidal activity. Moreover, the natural compound 3 has been isolated for the first time. Experimental investigation combined with theoretical study advances knowledge about the enzyme binding site mode of interaction and contributes to the design of new bioactive drugs against Leishmania infection. 相似文献
60.
Danielle Cristina Zimmermann-Franco Bruna Esteves Leticia Moroni Lacerda Isabela de Oliveira Souza Juliana Alves dos Santos Nícolas de Castro Campos Pinto Elita Scio Adilson David da Silva Gilson Costa Macedo 《Bioorganic & medicinal chemistry》2018,26(17):4898-4906
Resveratrol is a natural polyphenol found mainly on red grapes and in red wine, pointed as an important anti-inflammatory/immunomodulatory molecule. However, its bioavailability problems have limited its use encouraging the search for new alternatives agents. Thus, in this study, we synthetize 12 resveratrol analogues (6 imines, 1 thioimine and 5 hydrazones) and investigated its cytotoxicity, antioxidant activity and in vitro anti-inflammatory/immunomodulatory properties. The most promising compounds were also evaluated in vivo. The results showed that imines presented less cytotoxicity, were more effective than resveratrol on DPPH scavenger and exhibited an anti-inflammatory profile. Among them, the imines with a radical in the para position, on the ring B, not engaged in an intramolecular hydrogen-interaction, showed more prominent anti-inflammatory activity modulating, in vivo, the edema formation, the inflammatory infiltration and cytokine levels. An immunomodulatory activity also was observed in these molecules. Thus, our results suggest that imines with these characteristics presents potential to control inflammatory disorders. 相似文献