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31.
Joshua M. Thurman Maria Wong Brandon Renner Ashley Frazer-Abel Patricia C. Giclas Melanie S. Joy Diana Jalal Milena K. Radeva Jennifer Gassman Debbie S. Gipson Frederick Kaskel Aaron Friedman Howard Trachtman 《PloS one》2015,10(9)
Background
Recent pre-clinical studies have shown that complement activation contributes to glomerular and tubular injury in experimental FSGS. Although complement proteins are detected in the glomeruli of some patients with FSGS, it is not known whether this is due to complement activation or whether the proteins are simply trapped in sclerotic glomeruli. We measured complement activation fragments in the plasma and urine of patients with primary FSGS to determine whether complement activation is part of the disease process.Study Design
Plasma and urine samples from patients with biopsy-proven FSGS who participated in the FSGS Clinical Trial were analyzed.Setting and Participants
We identified 19 patients for whom samples were available from weeks 0, 26, 52 and 78. The results for these FSGS patients were compared to results in samples from 10 healthy controls, 10 patients with chronic kidney disease (CKD), 20 patients with vasculitis, and 23 patients with lupus nephritis.Outcomes
Longitudinal control of proteinuria and estimated glomerular filtration rate (eGFR).Measurements
Levels of the complement fragments Ba, Bb, C4a, and sC5b-9 in plasma and urine.Results
Plasma and urine Ba, C4a, sC5b-9 were significantly higher in FSGS patients at the time of diagnosis than in the control groups. Plasma Ba levels inversely correlated with the eGFR at the time of diagnosis and at the end of the study. Plasma and urine Ba levels at the end of the study positively correlated with the level of proteinuria, the primary outcome of the study.Limitations
Limited number of patients with samples from all time-points.Conclusions
The complement system is activated in patients with primary FSGS, and elevated levels of plasma Ba correlate with more severe disease. Measurement of complement fragments may identify a subset of patients in whom the complement system is activated. Further investigations are needed to confirm our findings and to determine the prognostic significance of complement activation in patients with FSGS. 相似文献32.
33.
Milena S. Espíndola Leonardo J. G. Lima Luana S. Soares Maira C. Cacemiro Fabiana A. Zambuzi Matheus de Souza Gomes Laurence R. Amaral Valdes R. Bollela Olindo A. Martins-Filho Fabiani G. Frantz 《PloS one》2015,10(12)
Background
Successful highly active antiretroviral therapy (HAART) has changed the outcome of AIDS patients worldwide because the complete suppression of viremia improves health and prolongs life expectancy of HIV-1+ patients. However, little attention has been given to the immunological profile of patients under distinct HAART regimens. This work aimed to investigate the differences in the immunological pattern of HIV-1+ patients under the first- or second-line HAART in Brazil.Methods
CD4+ T cell counts, Viral load, and plasma concentration of sCD14, sCD163, MCP-1, RANTES, IP-10, IL-1β, IL-6, TNF-α, IL-12, IFN-α, IFN-γ, IL-4, IL-5, and IL-10 were assessed for immunological characterization of the following clinical groups: Non-infected individuals (NI; n = 66), HIV-1+ untreated (HIV; n = 46), HIV-1+ treated with first-line HAART (HAART 1; n = 15); and HIV-1+ treated with second-line HAART (HAART 2; n = 15).Results
We found that the immunological biosignature pattern of HAART 1 is similar to that of NI individuals, especially in patients presenting slow progression of the disease, while patients under HAART 2 remain in a moderate inflammatory state, which is similar to that of untreated HIV patients pattern. Network correlations revealed that differences in IP-10, TNF-α, IL-6, IFN-α, and IL-10 interactions were primordial in HIV disease and treatment. Heat map and decision tree analysis identified that IP-10>TNF-α>IFN-α were the best respective HAART segregation biomarkers.Conclusion
HIV patients in different HAART regimens develop distinct immunological biosignature, introducing a novel perspective into disease outcome and potential new therapies that consider HAART patients as a heterogeneous group. 相似文献34.
Milena Nasi Sara De Biasi Elena Bianchini Lara Gibellini Marcello Pinti Tiziana Scacchetti Tommaso Trenti Vanni Borghi Cristina Mussini Andrea Cossarizza 《PloS one》2015,10(1)
Background
An accurate and affordable CD4+ T cells count is an essential tool in the fight against HIV/AIDS. Flow cytometry (FCM) is the “gold standard” for counting such cells, but this technique is expensive and requires sophisticated equipment, temperature-sensitive monoclonal antibodies (mAbs) and trained personnel. The lack of access to technical support and quality assurance programs thus limits the use of FCM in resource-constrained countries. We have tested the accuracy, the precision and the carry-over contamination of Partec CyFlow MiniPOC, a portable and economically affordable flow cytometer designed for CD4+ count and percentage, used along with the “CD4% Count Kit-Dry”.Materials and Methods
Venous blood from 59 adult HIV+ patients (age: 25–58 years; 43 males and 16 females) was collected and stained with the “MiniPOC CD4% Count Kit-Dry”. CD4+ count and percentage were then determined in triplicate by the CyFlow MiniPOC. In parallel, CD4 count was performed using mAbs and a CyFlow Counter, or by a dual platform system (from Beckman Coulter) based upon Cytomic FC500 (“Cytostat tetrachrome kit” for mAbs) and Coulter HmX Hematology Analyzer (for absolute cell count).Results
The accuracy of CyFlow MiniPOC against Cytomic FC500 showed a correlation coefficient (CC) of 0.98 and 0.97 for CD4+ count and percentage, respectively. The accuracy of CyFlow MiniPOC against CyFlow Counter showed a CC of 0.99 and 0.99 for CD4 T cell count and percentage, respectively. CyFlow MiniPOC showed an excellent repeatability: CD4+ cell count and percentage were analyzed on two instruments, with an intra-assay precision below ±5% deviation. Finally, there was no carry-over contamination for samples at all CD4 values, regardless of their position in the sequence of analysis.Conclusion
The cost-effective CyFlow MiniPOC produces rapid, reliable and accurate results that are fully comparable with those from highly expensive dual platform systems. 相似文献35.
Antonio Bevilacqua Monica Mischitelli Valeria Pietropaolo Emanuela Ciuffreda Milena Sinigaglia Maria Rosaria Corbo 《PloS one》2015,10(10)
Alicyclobacillus acidoterrestris is the main cause of most spoilage problems in fruit juices and acidic products. Since soil borne species often contaminate fruit juices and do not need strict extreme requirements for survival, it is a great concern to investigate whether and how soil species could evolve from their ecological niches in microbial community to new environments as fruit juices. In this study, 23 isolates of thermo-acidophilic, spore-forming bacteria from soil were characterized by cultural and molecular methods. In addition, 2 strains isolated from a spoilage incident in pear juice were typed. Strains phenotyping showed that they could be grouped into 3 different clusters, and some isolates showed identical or quite similar patterns. Analyzing pH and temperature ranges for growth, the majority of strains were able to grow at values described for many species of Alicyclobacillus. Qualitative utilization of lysine, arginine and indole production from tryptophan revealed, for the first time, deamination of lysine and decarboxylation of arginine. Resistance to 5% NaCl as well as the ability to hydrolyze starch and gelatin, nitrate reduction, catalase and oxidase activities confirmed literature evidences. Examining of 16S rRNA, showed that isolates were divided into three blocks represented by effectively soil species and strains that are moving from soil to other possible growing source characterized by parameters that could strongly influence bacterial survival. RAPD PCR technique evidenced a great variability in banding patterns and, although it was not possible to obtain genotypically well-distinguished groups, it was feasible to appreciate genetic similarity between some strains. In conclusion, the investigation of a microbial community entails a combination of metagenomic and classic culture-dependent approaches to expand our knowledge about Alicyclobacillus and to look for new subspecies. 相似文献
36.
Isolation and characterization of calf liver thioredoxin 总被引:10,自引:0,他引:10
N E Engstr?m A Holmgren A Larsson S S?derh?ll 《The Journal of biological chemistry》1974,249(1):205-210
37.
Surya K. Maharjan Milena Holmgren Frans Bongers Jan J. Wieringa William D. Hawthorne 《Biotropica》2011,43(5):552-561
Plant morphological and physiological traits affect the way plants tolerate environmental stresses and therefore play an important role in shaping species distribution patterns in relation to environmental gradients. Despite our growing knowledge on the role of functional traits in structuring plant communities, few studies have tested their importance at large scales in the wet tropics. Here, we describe the distribution patterns of the most important West African rain forest timber species along the regional rainfall gradient and relate them to their functional traits. We found that the distribution patterns of 25 out of the 31 studied species (80%) were significantly related to mean annual rainfall. Shade tolerance and drought resistance were identified as the main strategy axes of variation. Wood density and leaf deciduousness emerged as the best predictor traits of species position along the rainfall gradient, explaining respectively 32 and 15 percent of the variation. Species traits tended to show stronger relationships with estimated optimum annual rainfall for each species than to the extreme rainfall conditions where they occur. The significant role of rainfall in shaping timber species distribution and the strong relationships between species traits and rainfall indicate that changes in climate, especially declining rainfall, could have strong effects on species composition and abundance in these tropical forests. 相似文献
38.
A name (Eremogone loisiae) is provided for those plants from northern Utah and southeastern Idaho that have gone under the misapplied name Eremogone kingii subsp. uintahensis. Eremogone loisiae, named in honor of Lois A. Arnow, is distinguished from E. kingii by its longer and narrower, flexuous leaves and its longer sepals, petals, styles, capsules, and seeds. 相似文献
39.
40.
Milena Lima de Moraes Renata de Faria Barbosa Raquel Espírito Santo Flávia da Silva Santos Edgar Francisco Oliveira de Jesus Fátima Lúcia de Carvalho Sardinha Maria das Graças Tavares do Carmo 《Biological trace element research》2011,139(2):126-136
Adolescence is marked by intensive growth and development. When pregnancy occurs during this period of the mother’s growth,
there is an increase in her nutritional needs. The aim of this study was to determine the levels of calcium, iron, copper,
and zinc in maternal plasma, the placenta, and in the cord plasma of pregnant teenagers and adults. A total of 80 sets of
maternal plasma, placentas, and cord plasma (40 from teenagers and 40 from adults) were analyzed using synchrotron radiation
total reflection X-ray fluorescence. The levels of calcium, copper, and zinc in the maternal and cord plasma from teenagers
were not significantly different than those from adults. Iron levels in the teenagers maternal and cord plasma were higher
than in the adults. All of the minerals analyzed were present at higher levels in the placentas from adults than those from
teenagers. However, the low quantities of placental calcium, iron, copper, and zinc in the teenagers do not compromise the
levels of these minerals in the cord plasma. Future research regarding the placental transport of these minerals is recommended
to investigate the efficiency of mechanisms of transfer of these minerals in pregnant teenagers. 相似文献