749 research outputs found
Cutaneous streptococcal abscess treated by photodynamic therapy
Background: Photodynamic therapy has been investigated in different areas of health through experimental conditions. Its action can alter fundamental structures for the survival of microorganisms without any development of microbial resistance.Materials and Methods: Young sheep presenting with abscess in the left forelimb caused by Streptococcus spp. was previously treated with antibiotics. There was no clinical improvement with the treatments, and the bacteria presented sensitivity in vitro. Therefore, Photodynamic therapy associating methylene blue and red laser (660 nm) was used to treat the abscess.Results: After a day of treatment, complete healing was witnessed with no recurrence was observed during the 3-month follow-up period.Conclusion: The scientific results of the antimicrobial effect of PDT proved to be a therapeutic option with great potential for clinical application.Keywords: Photoinactivation, Laser, Sheep, Streptococcus spp
Brazilian Plasmodium falciparum isolates: investigation of candidate polymorphisms for artemisinin resistance before introduction of artemisinin-based combination therapy
<p>Abstract</p> <p>Background</p> <p>This study was performed to better understand the genetic diversity of known polymorphisms in <it>pfatpase6 </it>and <it>pfmdr1 </it>genes before the introduction of ACT in Brazil, in order to get a genotypic snapshot of <it>Plasmodium falciparum </it>parasites that may be used as baseline reference for future studies.</p> <p>Methods</p> <p>Parasites from <it>P. falciparum </it>samples collected in 2002, 2004 and 2006-2007 were genotyped using PCR and DNA sequencing at codons 86, 130, 184, 1034, 1042, 1109 and 1246 for <it>pfmdr1 </it>gene, and 243, 263, 402, 431, 623, 630, 639, 683, 716, 776, 769 and 771 for <it>pfatpase6 </it>gene.</p> <p>Results</p> <p>A <it>pfmdr1 </it>haplotype NEF/CDVY was found in 97% of the samples. In the case of <it>pfatpase6</it>, four haplotypes, wild-type (37%), 630 S (35%), 402 V (5%) and double-mutant 630 S + 402 V (23%), were detected.</p> <p>Conclusion</p> <p>Although some polymorphism in <it>pfmdr1 </it>and <it>pfatpase6 </it>were verified, no reported haplotypes in both genes that may mediate altered response to ACT was detected before the introduction of this therapy in Brazil. Thus, the haplotypes herein described can be very useful as a baseline reference of <it>P. falciparum </it>populations without ACT drug pressure.</p
Variation of selfing rate and inbreeding depression among individuals and across generations within an admixed Cedrus population
[EN] We investigated the variation and short-term evolution of the selfing rate and inbreeding depression (ID) across three generations within a cedar forest that was established from admixture ca 1860. The mean selfing rate was 9.5%, ranging from 0 to 48% among 20 seed trees (estimated from paternally inherited chloroplast DNA). We computed the probability of selfing for each seed and we investigated ID by comparing selfed and outcrossed seeds within progenies, thus avoiding maternal effects. In all progenies, the germination rate was high (88-100%) and seedling mortality was low (0-12%). The germination dynamics differed significantly between selfed and outcrossed seeds within progenies in the founder gene pool but not in the following generations. This transient effect of selfing could be attributed to epistatic interactions in the original admixture. Regarding the seedling growth traits, the ID was low but significant: 8 and 6% for height and diameter growth, respectively. These rates did not vary among generations, suggesting minor gene effects. At this early stage, outcrossed seedlings outcompeted their selfed relatives, but not necessarily other selfed seedlings from other progenies. Thus, purging these slightly deleterious genes may only occur through within-family selection. Processes that maintain a high level of genetic diversity for fitness-related traits among progenies also reduce the efficiency of purging this part of the genetic load. © 2011 Macmillan Publishers Limited All rights reserved.
Guardar / Salir Siguiente >This work has been partially supported by Grant PPI-00-04 from the Polytechnic University of Valencia (Spain). We thank B Fady and E Klein as well as two anonymous reviewers for their helpful comments on a previous version of the paper. We acknowledge B Jouaud, W Brunetto, F Jean and H Picot for seed collection and processing and laboratory assistance, as well as P Brahic and staff from the Experimental Nursery of Aix-Les Milles for nursery cares.Ferriol Molina, M.; Pichot, C.; Lefevre, F. (2011). Variation of selfing rate and inbreeding depression among individuals and across generations within an admixed Cedrus population. Heredity. 106(1):146-157. https://doi.org/10.1038/hdy.2010.451461571061Barret SH, Eckert CG (1990). Variation and evolution of mating systems in seed plants. In: Kawano S (ed). Biological Approaches and Evolutionary Trends in Plants. Academic Press: London. pp 230–254.Benton TG, Plaistow SJ, Coulson TN (2006). Complex population dynamics and complex causation: devils, details and demography. Proc R Soc B Biol Sci 273: 1173–1181.Bower AD, Aitken SN (2007). Mating system and inbreeding depression in whitebark pine (Pinus albicaulis Engelm.). Tree Genet Genomes 3: 379–388.Byers DL, Waller DM (1999). Do plant populations purge their genetic load? Effects of population size and mating history on inbreeding depression. Annu Rev Ecol Syst 30: 479–513.Cointat M (1996). Le roman du cèdre. Revue Forestière Française 48: 503–526.Collevatti RG, Grattapaglia D, Duvall J (2001). High resolution microsatellite based analysis of the mating system allows the detection of significant biparental inbreeding in Caryocar brasiliense, an endangered tropical tree species. Heredity 86: 60–67.Cottrell JE, White IMS (1995). The use of isozyme genetic markers to estimate the rate of outcrossing in a Sitka pruce (Picea sitchensis (Bong.) Carr.) seed orchard in Scotland. New Forests 10: 111–122.Coulson T, Benton TG, Lundberg P, Dall SRX, Kendall BE (2006). Putting evolutionary biology back in the ecological theatre: a demographic framework mapping genes to communities. Evol Ecol Res 8: 1155–1171.Durel CE, Bertin P, Kremer A (1996). Relationship between inbreeding depression and inbreeding coefficient in maritime pine (Pinus pinaster). Theor Appl Genet 92: 347–356.Eriksson E (2006). Thinning operations and their impact on biomass production in stands of Norway spruce and Scots pine. Biomass Bioenergy 30: 848–854.Fady B, Lefèvre F, Reynaud M, Vendramin GG, Bou Dagher-Karrat M, Anzidei M et al. (2003). Gene flow among different taxonomic units: evidence from nuclear and cytoplasmic markers in Cedrus plantation forests. Theor Appl Genet 107: 1132–1138.Farris MA, Mitton JB (1984). Population density, outcrossing rate, and heterozygote superiority in ponderosa pine. Evolution 38: 1151–1154.Favre-Duchartre M (1970). Des Ovules Aux Graines. Monographie 8. Masson et Cie.: Paris.Franklin EC (1969). Inbreeding Depression in Metrical Traits of Loblolly Pine (Pinus taeda L.) as a Result of Self-pollination. North Carolina State University: Raleigh, NC. Technical report No 40, School of Forest Resources.Gregorius HR, Ziehe M, Ross MD (1987). Selection caused by self-fertilization I. Four measures of self-fertilization and their effects on fitness. Theor Popul Biol 31: 91–115.Hamrick JL, Godt MJ (1989). Allozyme diversity in plant species. In: Brown AHD, Al Kahler MC, Weir BS (eds). Plant Population Genetics, Breeding, and Genetic Resources. Sinauer: Sunderland, MA. pp 43–63.Holsinger KE (1991). Mass-action models of plant mating systems—the evolutionary stability of mixed mating systems. Am Nat 138: 606–622.Husband BC, Schemske DW (1996). Evolution of the magnitude and timing of inbreeding depression in plants. Evolution 50: 54–70.Jones FA, Hamrick JL, Peterson CJ, Squiers ER (2006). Inferring colonization history from analyses of spatial genetic structure within populations of Pinus strobus and Quercus rubra. Mol Ecol 15: 851–861.Kärkkäinen K, Savolainen O (1993). The degree of early inbreeding depression determines the selfing rate at the seed stage: model and results from Pinus sylvestris (Scots pine). Heredity 71: 160–166.Keller LF, Waller DM (2002). Inbreeding effects in wild populations. Trends Ecol Evol 17: 230–241.Klein EK, Lavigne C, Gouyon PH (2006). Mixing of propagules from discrete sources at long distance: comparing an exponential tail to an exponential. BMC Ecol 6: 3.Knowles P, Furnier GR, Aleksiuk MK, Perry DJ (1987). Significant levels of self-fertilization in natural populations of tamarack. Can J Bot 65: 1087–1091.Koelewijn HP, Koski V, Savolainen O (1999). Magnitude and timing of inbreeding depression in Scots pine (Pinus sylvestris L.). Evolution 53: 758–768.Kremer A (1994). Genetic diversity and phenotypic variability of forest trees. Genet Sel Evol 26: s105–s123.Krouchi F, Derridj A, Lefèvre F (2004). Year and tree effect on reproductive organisation of Cedrus atlantica in a natural forest. For Ecol Manage 197: 181–189.Lande R (1988). Genetics and demography in biological conservation. Science 241: 1455–1460.Ledig FT (1986). Heterozygosity, heterosis, and fitness in outbreeding plants. In: Soulé ME (ed). Conservation Biology: the Science of Scarcity and Diversity. Sinauer Ass: Sunderland. pp 77–104.Lee JK, Nordheim EV, Kang H (1996). Inference for lethal gene estimation with application in plants. Biometrics 52: 451–462.Lefèvre F, Fady B, Fallour-Rubio D, Ghosn D, Bariteau M (2004). Impact of founder population, drift and selection on the genetic diversity of a recently translocated tree population. Heredity 93: 542–550.Marquardt PE, Epperson BK (2004). Spatial and population genetic structure of microsatellites in white pine. Mol Ecol 13: 3305–3315.Morgante M, Vendramin GG, Rossi P (1991). Effects of stand density on outcrossing rate in two Norway spruce (Picea abies) populations. Can J Bot 69: 2704–2708.Mosseler A, Major JE, Simpson JD, Daigle B, Lange K, Park YS et al. (2000). Indicators of population viability in red spruce, Picea rubens. I. Reproductive traits and fecundity. Can J Bot 78: 928–940.Naydenov KD, Tremblay FM, Alexandrov A, Fenton NJ (2005). Structure of Pinus sylvestris L. populations in Bulgaria revealed by chloroplast microsatellites and terpenes analysis : provenance tests. Biochem Syst Ecol 33: 1226–1245.Neale DB, Adams WT (1985). The mating system in natural and shelterwood stands of Douglas-fir. Theor Appl Genet 71: 201–207.Notivol E, Garcia-Gil MR, Alia R, Savolainen O (2007). Genetic variation of growth rhythm traits in the limits of a latitudinal cline in Scots pine. Can J For Res 37: 540–551.O’Connell LM, Russell J, Ritland K (2004). Fine-scale estimation of outcrossing in western redcedar with microsatellite assay of bulked DNA. Heredity 93: 443–449.Parducci L, Szmidt AE, Madaghiele A, Anzidei M, Vendramin GG (2001). Genetic variation at chloroplast microsatellites (CpSSRs) in Abies nebrodensis (Lojac.) Mattei and three neighboring Abies species. Theor Appl Genet 102: 733–740.Parraguirre-Lezama C, Vargas-Hernández JJ, Ramirez-Vallejo P, Ramirez Herrera C (2004). Mating system in four natural populations of Pinus greggii Engelm. Agrociencia 38: 107–119.Petit RJ, Hampe A (2006). Some evolutionary consequences of being a tree. Annu Rev Ecol Evol Syst 37: 187–214.Pichot C, Bastien C, Courbet F, Demesure-Musch B, Dreyfus P, Fady B et al. (2006). Déterminants et conséquences de la qualité génétique des graines et semis lors de la phase initiale de régénération naturelle des peuplements forestiers. In: 6e Colloque National du BRG ; La Rochelle 2006/10/02-04. Les Actes du Bureau des Ressources Génétiques 6: 277–297.Remington DL, O’Malley DM (2000a). Whole-genome characterization of embryonic stage inbreeding depression in a selfed loblolly pine family. Genetics 155: 337–348.Remington DL, O’Malley DM (2000b). Evaluation of major genetic loci contributing to inbreeding depression for survival and early growth in a selfed family of Pinus taeda. Evolution 54: 1580–1589.Restoux G, Silva DE, Sagnard F, Torre F, Klein E, Fady B (2008). Life at the margin: the mating system of Mediterranean conifers. Web Ecol 8: 94–102.Ribeiro MM, Mariette S, Vendramin GG, Szmidt AE, Plomion C, Kremer A (2002). Comparison of genetic diversity estimates within and among populations of maritime pine using chloroplast simple-sequence repeat and amplified fragment length polymorphism data. Mol Ecol 11: 869–877.Ritland K, El-Kassaby YA (1985). The nature of inbreeding in a seed orchard of Douglas fir as shown by an efficient multi-locus model. Theor Appl Genet 71: 375–384.Ritland K, Travis S (2004). Inferences involving individual coefficients of relatedness and inbreeding in natural populations of Abies. For Ecol Manage 197: 171–180.Robledo-Arnuncio JJ, Alia R, Gil L (2004). Increased selfing and correlated paternity in a small population of a predominantly outcrossing conifer, Pinus sylvestris. Mol Ecol 13: 2567–2577.Rouault G, Turgeon J, Candau JN, Roques A, Aderkas P (2004). Oviposition strategies of conifer seed chalcids in relation to host phenology. Naturwissenschaften 91: 472–480.Savolainen O, Kärkkäinen K, Kuittinen H (1992). Estimating numbers of embryonic lethals in conifers. Heredity 69: 308–314.Scofield DG, Schultz ST (2006). Mitosis, stature and evolution of plant mating systems: low-Phi and high-Phi plants. Proc R Soc B Biol Sci 273: 275–282.Shaw DV, Allard RW (1982). Estimation of outcrossing rates in douglas-fir using isoenzyme markers. Theor Appl Genet 62: 113–120.Skrøppa T (1996). Diallel crosses in Picea abies. II. Performance and inbreeding depression of selfed families. For Genet 3: 69–79.Sorensen FC (1997). Effects of sib mating and wind pollination on nursery seedling size, growth components, and phenology of Douglas-fir seed-orchard progenies. Can J For Res 27: 557–566.Sorensen FC (1999). Relationship between self-fertility, allocation of growth, and inbreeding depression in three coniferous species. Evolution 53: 417–425.Sorensen FC (2001). Effect of population outcrossing rate on inbreeding depression in Pinus contorta var. murrayana seedlings. Scand J For Res 16: 391–403.Sorensen FC, Adams WT (1993). Self fertility and natural selfing in three Oregon Cascade populations of lodgepole pine. In: Lindgren D (ed). Pinus contorta—From Untamed Forest to Domesticated Crop. Department of Forest Genetics and Plant Physiology, Sweden University of Agricultural Science: Umea, Sweden. Report 11, pp 358–374.Sorensen FC, Miles RS (1974). Self-pollination effects on Douglas fir and ponderosa pine seeds and seedlings. Silvae Genet 23: 135–138.Sorensen FC, Miles RS (1982). Inbreeding depression in height, height growth, and survival of Douglas-fir, ponderosa pine, and noble fir to 10 years of age. For Sci 28: 283–292.Terrab A, Paun O, Talavera S, Tremetsberger K, Arista M, Stuessy TF (2006). Genetic diversity and population structure in natural populations of Moroccan Atlas cedar (Cedrus atlantica; Pinaceae) determined with cpSSR markers. Am J Bot 93: 1274–1280.Vendramin GG, Lelli L, Rossi P, Morgante M (1996). A set of primers for the amplification of 20 chloroplast microsatellites in Pinaceae. Mol Ecol 5: 595–598.White TL, Adams WT, Neale DB (2007). Forest Genetics. CABI Publisher: Cambridge, MA. pp 149–186.Wilcox MD (1983). Inbreeding depression and genetic variances estimated from self- and cross- pollinated families of Pinus radiata. Silvae Genet 32: 89–96.Williams CG (2007). Re-thinking the embryo lethal system within the Pinaceae. Can J Bot 85: 667–677.Williams CG (2008). Selfed embryo death in Pinus taeda: a phenotypic profile. New Phytol 178: 210–222.Williams CG, Auckland LD, Reynolds MM, Leach KA (2003). Overdominant lethals as part of the conifer embryo lethal system. Heredity 91: 584–592.Wilson R (1923). Life history of Cedrus atlantica. Bot Gaz 75: 203–208.Yazdani R, Muona O, Rudin D, Szmidt AE (1985). Genetic structure of a Pinus sylvestris L. seed-tree stand and naturally regenerated understory. For Sci 31: 430–436
Prostatectomia radical laparoscópica versus aberta: margens cirúrgicas
A prostatectomia radical por via laparoscópica é atualmente uma via de abordagem al-
ternativa à via clássica.
Objetivos: Pretende-se comparar os resultados oncológicos, nomeadamente as margens
cirúrgicas, dos dois tipos de abordagens.
Material e métodos: Em Setembro de 2012 deu-se início, a um estudo prospetivo durante
10 meses, com o objetivo de comparar os resultados da prostatectomia radical laparos-
cópica versus aberta. Incluiu-se no estudo apenas os tumores de baixo risco e de risco
intermédio.
Avaliou-se diversos parâmetros: idade, PSA inicial, Gleason na biópsia, duração da ci-
rurgia, número de transfusões sanguíneas, margens cirúrgicas, complicações, Gleason e
estádio TNM na peça operatória.
Resultados: Foram incluídos no estudo 45 doentes, 24 operados por via laparoscópica
e 21 por via aberta. No grupo da abordagem laparoscópica, dos 24 doentes 70,8% (17)
apresentaram margens negativas, 25% (6) margens positivas e 4,17% (1) não avaliável.
No grupo da abordagem aberta dos 21 doentes 66,7% (14) apresentaram margens nega-
tivas, 28,6% (6) margens positivas e 4,76% (1) não avaliável.
A aplicação de um teste do qui-quadrado considerando dois grupos de margens: po-
sitivas e não positivas, resultou num valor observado do qui-quadrado igual a 0,07
(p valor = 0,79), pelo que se concluiu não haver diferenças signifi cativas na distribuição
das margens positivas nos dois grupos de abordagem cirúrgica.
Procurámos avaliar se a distribuição dos tumores classifi cados como T2a, T2b, T2c, T3a
e T3b, era idêntica nos dois grupos. Obtivemos um valor observado para o qui-quadrado
de 1,44 (p valor = 0,23), que nos permitiu concluir que a distribuição dos dois grupos de
estádios tumorais não é signifi cativamente diferente nos dois tipos de cirurgia utilizados.
Conclusões: Os resultados obtidos neste estudo revelam que não há associação entre as
margens e o tipo de abordagem cirúrgica bem como, não existe também associação entre
os estádios tumorais e os dois tipos de abordagem cirúrgica. Através das diferentes análises elaboradas neste estudo podemos concluir que a pros-
tatectomia radical laparoscópica poderá ser uma alternativa válida à abordagem aberta
nos tumores de baixo risco e de risco intermédio. Apesar do número reduzido de casos,
pensamos que é uma técnica segura do ponto de vista oncológico, não estando reservada
apenas a centros de alto volume
Predictors of persistently positive Mycobacterium-tuberculosis-specific interferon-gamma responses in the serial testing of health care workers
<p>Abstract</p> <p>Background</p> <p>Data on the performance of Mycobacterium-tuberculosis-specific interferon-(IFN)-γ release assays (IGRAs) in the serial testing of health care workers (HCWs) is limited. The objective of the present study was to determine the frequency of IGRA conversions and reversions and to identify predictors of persistent IGRA positivity among serially tested German HCWs in the absence of recent extensive tuberculosis (TB) exposure.</p> <p>Methods</p> <p>In this observational cohort-study HCWs were prospectively recruited within occupational safety and health measures and underwent a tuberculin skin test (TST) and the IGRA QuantiFERON<sup>®</sup>-TB Gold In-Tube (QFT-GIT) at baseline. The QFT-GIT was repeated 18 weeks later in the median. QFT-GIT conversions (and reversions) were defined as baseline IFN-γ < 0.35 IU/ml and follow-up IFN-γ ≥ 0.35 IU/ml (and vice versa). Predictors of persistently positive QFT-GIT results were calculated by logistic regression analysis.</p> <p>Results</p> <p>In total, 18 (9.9%) and 15 (8.2%) of 182 analyzed HCWs were QFT-GIT-positive at baseline and at follow-up, respectively. We observed a strong overall agreement between baseline and follow-up QFT-GIT results (κ = 0.70). Reversions (6/18, 33.3%) occurred more frequently than conversions (3/162, 1.9%). Age and positive prior and recent TST results independently predicted persistent QFT-GIT positivity. Furthermore, the chance of having persistently positive QFT-GIT results raised about 3% with each additional 0.1 IU/ml increase in the baseline IFN-γ response (adjusted odds ratio 1.03, 95% confidence interval 1.01-1.04). No active TB cases were detected within an observational period of more than two years.</p> <p>Conclusions</p> <p>The QFT-GIT's utility for the application in serial testing was limited by a substantial proportion of reversions. This shortcoming could be overcome by the implementation of a borderline zone for the interpretation of QFT-GIT results. However, further studies are needed to clearly define the within-subject variability of the QFT-GIT and to confirm that increasing age, concordantly positive TST results, and the extend of baseline IFN-γ responses may predict the persistence of QFT-GIT positivity over time in serially tested HCWs with only a low or medium TB screening risk in a TB low-incidence setting.</p
Synthesis and characterization of VO2-based thermochromic thin films for energy-efficient windows
Thermochromic VO2 thin films have successfully been grown on SiO2-coated float glass by reactive DC and pulsed-DC magnetron sputtering. The influence of substitutional doping of V by higher valence cations, such as W, Mo, and Nb, and respective contents on the crystal structure of VO2 is evaluated. Moreover, the effectiveness of each dopant element on the reduction of the intrinsic transition temperature and infrared modulation efficiency of VO2 is discussed. In summary, all the dopant elements--regardless of the concentration, within the studied range-- formed a solid solution with VO2, which was the only compound observed by X-ray diffractometry. Nb showed a clear detrimental effect on the crystal structure of VO2. The undoped films presented a marked thermochromic behavior, specially the one prepared by pulsed-DC sputtering. The dopants effectively decreased the transition of VO2 to the proximity of room temperature. However, the IR modulation efficiency is markedly affected as a consequence of the increased metallic character of the semiconducting phase. Tungsten proved to be the most effective element on the reduction of the semiconducting-metal transition temperature, while Mo and Nb showed similar results with the latter being detrimental to the thermochromism
PCR colorimetric dot-blot assay and clinical pretest probability for diagnosis of Pulmonary Tuberculosis in Smear-Negative patients
<p>Abstract</p> <p>Background</p> <p>Smear-negative pulmonary tuberculosis (SNPTB) accounts for 30% of Pulmonary Tuberculosis (PTB) cases reported annually in developing nations. Polymerase chain reaction (PCR) may provide an alternative for the rapid detection of <it>Mycobacterium tuberculosis </it>(MTB); however little data are available regarding the clinical utility of PCR in SNPTB, in a setting with a high burden of TB/HIV co-infection.</p> <p>Methods</p> <p>To evaluate the performance of the PCR dot-blot in parallel with pretest probability (Clinical Suspicion) in patients suspected of having SNPTB, a prospective study of 213 individuals with clinical and radiological suspicion of SNPTB was carried out from May 2003 to May 2004, in a TB/HIV reference hospital. Respiratory specialists estimated the pretest probability of active disease into high, intermediate, low categories. Expectorated sputum was examined by direct microscopy (Ziehl-Neelsen staining), culture (Lowenstein Jensen) and PCR dot-blot. Gold standard was based on culture positivity combined with the clinical definition of PTB.</p> <p>Results</p> <p>In smear-negative and HIV subjects, active PTB was diagnosed in 28.4% (43/151) and 42.2% (19/45), respectively. In the high, intermediate and low pretest probability categories active PTB was diagnosed in 67.4% (31/46), 24% (6/25), 7.5% (6/80), respectively. PCR had sensitivity of 65% (CI 95%: 50%–78%) and specificity of 83% (CI 95%: 75%–89%). There was no difference in the sensitivity of PCR in relation to HIV status. PCR sensitivity and specificity among non-previously TB treated and those treated in the past were, respectively: 69%, 43%, 85% and 80%. The high pretest probability, when used as a diagnostic test, had sensitivity of 72% (CI 95%:57%–84%) and specificity of 86% (CI 95%:78%–92%). Using the PCR dot-blot in parallel with high pretest probability as a diagnostic test, sensitivity, specificity, positive and negative predictive values were: 90%, 71%, 75%, and 88%, respectively. Among non-previously TB treated and HIV subjects, this approach had sensitivity, specificity, positive and negative predictive values of 91%, 79%, 81%, 90%, and 90%, 65%, 72%, 88%, respectively.</p> <p>Conclusion</p> <p>PCR dot-blot associated with a high clinical suspicion may provide an important contribution to the diagnosis of SNPTB mainly in patients that have not been previously treated attended at a TB/HIV reference hospital.</p
Enzymatic Shaving of the Tegument Surface of Live Schistosomes for Proteomic Analysis: A Rational Approach to Select Vaccine Candidates
Adult schistosome parasites can reside in the host bloodstream for decades surrounded by components of the immune system. It was originally proposed that their survival depended on the secretion of an inert bilayer, the membranocalyx, to protect the underlying plasma membrane from attack. We have investigated whether any proteins were exposed on the surface of live worms using incubation with selected hydrolases, in combination with mass spectrometry to identify released proteins. We show that a small number of parasite proteins are accessible to the enzymes and so could represent constituents of the membranocalyx. We also identified several proteins acquired by the parasite on contact with host cells. In addition, components of the cytolytic complement pathway were detected, but these appeared not to harm the worm, indicating that some of its own surface proteins could inhibit the lytic pathway. We suggest that, collectively, the ‘superficial’ parasite proteins may provide good candidates for a schistosome vaccine
Mercury exposure, malaria, and serum antinuclear/antinucleolar antibodies in amazon populations in Brazil: a cross-sectional study
BACKGROUND: Mercury is an immunotoxic metal that induces autoimmune disease in rodents. Highly susceptible mouse strains such as SJL/N, A.SW, B10.S (H-2(s)) develop multiple autoimmune manifestations after exposure to inorganic mercury, including lymphoproliferation, elevated levels of autoantibodies, overproduction of IgG and IgE, and circulating immune complexes in kidney and vasculature. A few studies have examined relationships between mercury exposures and adverse immunological reactions in humans, but there is little evidence of mercury-associated autoimmunity in humans. METHODS: To test the immunotoxic effects of mercury in humans, we studied communities in Amazonian Brazil with well-characterized exposures to mercury. Information was collected on diet, mercury exposures, demographic data, and medical history. Antinuclear and antinucleolar autoantibodies (ANA and ANoA) were measured by indirect immunofluorescence. Anti-fibrillarin autoantibodies (AFA) were measured by immunoblotting. RESULTS: In a gold mining site, there was a high prevalence of ANA and ANoA: 40.8% with detectable ANoA at ≥1:10 serum dilution, and 54.1% with detectable ANA (of which 15% had also detectable ANoA). In a riverine town, where the population is exposed to methylmercury by fish consumption, both prevalence and levels of autoantibodies were lower: 18% with detectable ANoA and 10.7% with detectable ANA. In a reference site with lower mercury exposures, both prevalence and levels of autoantibodies were much lower: only 2.0% detectable ANoA, and only 7.1% with detectable ANA. In the gold mining population, we also examined serum for AFA in those subjects with detectable ANoA (≥1:10). There was no evidence for mercury induction of this autoantibody. CONCLUSIONS: This is the first study to report immunologic changes, indicative of autoimmune dysfunction in persons exposed to mercury, which may also reflect interactions with infectious disease and other factors
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