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61.
Bretzel G Huber KL Kobara B Beissner M Piten E Herbinger KH Wiedemann FX Amekuse K Banla Kere A Helfrich K Fleischmann E Löscher T Diefenhardt A Nitschke J 《PLoS neglected tropical diseases》2011,5(7):e1228
Background
Since the early 1990s more than 1,800 patients with lesions suspicious for Buruli ulcer disease (BUD) have been reported from Togo. However, less than five percent of these were laboratory confirmed. Since 2007, the Togolese National Buruli Ulcer Control Program has been supported by the German Leprosy and Tuberculosis Relief Association (DAHW). Collaboration with the Department for Infectious Diseases and Tropical Medicine (DITM), University Hospital, Munich, Germany, allowed IS2404 PCR analysis of diagnostic samples from patients with suspected BUD during a study period of three years.Methodology/Principal Findings
The DAHW integrated active BUD case finding in the existing network of TB/Leprosy Controllers and organized regular training and outreach activities to identify BUD cases at community level. Clinically suspected cases were referred to health facilities for diagnosis and treatment. Microscopy was carried out locally, external quality assurance (EQA) at DITM. Diagnostic samples from 202 patients with suspected BUD were shipped to DITM, 109 BUD patients (54%) were confirmed by PCR, 43 (29.9%) by microscopy. All patients originated from Maritime Region. EQA for microscopy resulted in 62% concordant results.Conclusions/Significance
This study presents a retrospective analysis of the first cohort of clinically suspected BUD cases from Togo subjected to systematic laboratory analysis over a period of three years and confirms the prevalence of BUD in Maritime Region. Intensified training in the field of case finding and sample collection increased the PCR case confirmation rate from initially less than 50% to 70%. With a PCR case confirmation rate of 54% for the entire study period the WHO standards (case confirmation rate ≥50%) have been met. EQA for microscopy suggests the need for intensified supervision and training. In January 2011 the National Hygiene Institute, Lomé, has assumed the role of a National Reference Laboratory for PCR confirmation and microscopy. 相似文献62.
Ana Paula Carneiro Salgado Jamária Adriana Pinheiro Soares-Martins Luciana Garcia Andrade Jonas Dutra Albarnaz Paulo César Peregrino Ferreira Erna Geessien Kroon Cláudio Ant?nio Bonjardim 《Memórias do Instituto Oswaldo Cruz》2013,108(5):554-562
Interfering with cellular signal transduction pathways is a common
strategy used by many viruses to create a propitious intracellular environment
for an efficient replication. Our group has been studying cellular signalling
pathways activated by the orthopoxviruses Vaccinia (VACV) and Cowpox (CPXV) and
their significance to viral replication. In the present study our aim was to
investigate whether the GTPase Rac1 was an upstream signal that led to the
activation of MEK/ERK1/2, JNK1/2 or Akt pathways upon VACV or CPXV'' infections.
Therefore, we generated stable murine fibroblasts exhibiting negative dominance
to Rac1-N17 to evaluate viral growth and the phosphorylation status of ERK1/2,
JNK1/2 and Akt. Our results demonstrated that VACV replication, but not CPXV,
was affected in dominant-negative (DN) Rac1-N17 cell lines in which viral yield
was reduced in about 10-fold. Viral late gene expression, but not early, was
also reduced. Furthermore, our data showed that Akt phosphorylation was
diminished upon VACV infection in DN Rac1-N17 cells, suggesting that Rac1
participates in the phosphoinositide-3 kinase pathway leading to the activation
of Akt. In conclusion, our results indicate that while Rac1 indeed plays a role
in VACV biology, perhaps another GTPase may be involved in CPXV replication. 相似文献
63.
Lalhaba Oinam Gopakumar Changarathil Erna Raja Yen Xuan Ngo Hiroaki Tateno Aiko Sada Hiromi Yanagisawa 《Aging cell》2020,19(8)
Aging in the epidermis is marked by a gradual decline in barrier function, impaired wound healing, hair loss, and an increased risk of cancer. This could be due to age‐related changes in the properties of epidermal stem cells and defective interactions with their microenvironment. Currently, no biochemical tools are available to detect and evaluate the aging of epidermal stem cells. The cellular glycosylation is involved in cell–cell communications and cell–matrix adhesions in various physiological and pathological conditions. Here, we explored the changes of glycans in epidermal stem cells as a potential biomarker of aging. Using lectin microarray, we performed a comprehensive glycan profiling of freshly isolated epidermal stem cells from young and old mouse skin. Epidermal stem cells exhibited a significant difference in glycan profiles between young and old mice. In particular, the binding of a mannose‐binder rHeltuba was decreased in old epidermal stem cells, whereas that of an α2‐3Sia‐binder rGal8N increased. These glycan changes were accompanied by upregulation of sialyltransferase, St3gal2 and St6gal1 and mannosidase Man1a genes in old epidermal stem cells. The modification of cell surface glycans by overexpressing these glycogenes leads to a defect in the regenerative ability of epidermal stem cells in culture. Hence, our study suggests the age‐related global alterations in cellular glycosylation patterns and its potential contribution to the stem cell function. These glycan modifications detected by lectins may serve as molecular markers for aging, and further functional studies will lead us to a better understanding of the process of skin aging. 相似文献
64.
Jacco C. Karper Mark M. Ewing Margreet R. de Vries Saskia C. A. de Jager Erna A. B. Peters Hetty C. de Boer Anton-Jan van Zonneveld Johan Kuiper Eric G. Huizinga T. Harma C. Brondijk J. Wouter Jukema Paul H. A. Quax 《PloS one》2013,8(7)
Background
RP105 (CD180) is TLR4 homologue lacking the intracellular TLR4 signaling domain and acts a TLR accessory molecule and physiological inhibitor of TLR4-signaling. The role of RP105 in vascular remodeling, in particular post-interventional remodeling is unknown.Methods and Results
TLR4 and RP105 are expressed on vascular smooth muscle cells (VSMC) as well as in the media of murine femoral artery segments as detected by qPCR and immunohistochemistry. Furthermore, the response to the TLR4 ligand LPS was stronger in VSMC from RP105−/− mice resulting in a higher proliferation rate. In RP105−/− mice femoral artery cuff placement resulted in an increase in neointima formation as compared to WT mice (4982±974 µm2 vs.1947±278 µm2,p = 0.0014). Local LPS application augmented neointima formation in both groups, but in RP105−/− mice this effect was more pronounced (10316±1243 µm2 vs.4208±555 µm2,p = 0.0002), suggesting a functional role for RP105. For additional functional studies, the extracellular domain of murine RP105 was expressed with or without its adaptor protein MD1 and purified. SEC-MALSanalysis showed a functional 2∶2 homodimer formation of the RP105-MD1 complex. This protein complex was able to block the TLR4 response in whole blood ex-vivo. In vivo gene transfer of plasmid vectors encoding the extracellular part of RP105 and its adaptor protein MD1 were performed to initiate a stable endogenous soluble protein production. Expression of soluble RP105-MD1 resulted in a significant reduction in neointima formation in hypercholesterolemic mice (2500±573 vs.6581±1894 µm2,p<0.05), whereas expression of the single factors RP105 or MD1 had no effect.Conclusion
RP105 is a potent inhibitor of post-interventional neointima formation. 相似文献65.
Grazziotin A Pimentel FA Sangali S de Jong EV Brandelli A 《Bioresource technology》2007,98(16):3172-3175
A feather protein hydrolysate was produced using the keratinolytic bacterium Vibrio sp. strain kr2. Complete feather degradation was observed in medium containing up to 60 g L(-1) raw feathers. Cultivation on 40, 60 or 80 g L(-1) feathers for five days resulted in similar amounts of soluble protein, reaching maximum values around 2.5 g L(-1). Maximum yields of soluble protein were achieved at 30 degrees C and initial pH ranging from 6.0 to 8.0. Strain kr2 was effective in producing keratin hydrolysate from chicken feathers. Bacterial feather hydrolysate has the potential for utilization as an ingredient in animal feed or as organic fertilizer, thereby reducing the environmental impact of feather waste from the poultry industry. 相似文献
66.
67.
Letícia Muraro Wildner Maria Luiza Bazzo Susie Coutinho Liedke Christiane Louren?o Nogueira Gabriela Segat Simone Gon?alves Senna Aline Daiane Schlindwein Jaquelline Germano de Oliveira Darcita B Rovaris Claudio A Bonjardim Erna G Kroon Paulo CP Ferreira 《Memórias do Instituto Oswaldo Cruz》2014,109(3):356-361
The identification of mycobacteria is essential because tuberculosis (TB) and
mycobacteriosis are clinically indistinguishable and require different therapeutic
regimens. The traditional phenotypic method is time consuming and may last up to 60
days. Indeed, rapid, affordable, specific and easy-to-perform identification methods
are needed. We have previously described a polymerase chain reaction-based method
called a mycobacteria mobility shift assay (MMSA) that was designed for
Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria
(NTM) species identification. The aim of this study was to assess the MMSA for the
identification of MTC and NTM clinical isolates and to compare its performance with
that of the PRA-hsp65 method. A total of 204 clinical isolates (102
NTM and 102 MTC) were identified by the MMSA and PRA-hsp65. For
isolates for which these methods gave discordant results, definitive species
identification was obtained by sequencing fragments of the 16S rRNA and
hsp65 genes. Both methods correctly identified all MTC isolates. Among
the NTM isolates, the MMSA alone assigned 94 (92.2%) to a complex or species, whereas
the PRA-hsp65 method assigned 100% to a species. A 91.5% agreement
was observed for the 94 NTM isolates identified by both methods. The MMSA provided
correct identification for 96.8% of the NTM isolates compared with 94.7% for
PRA-hsp65. The MMSA is a suitable auxiliary method for routine
use for the rapid identification of mycobacteria. 相似文献
68.
Deghoyan A Heqimyan A Nikoghosyan A Dadasyan E Ayrapetyan S 《Electromagnetic biology and medicine》2012,31(2):132-142
Non thermal (NT) effect of direct radiation 4?Hz-modulated 90-160?GHz of Millimeter Waves (MMW) and preliminary MMW-treated physiological solution (PS) influence were studied on snail isolated neuron, rat's brain tissue hydration and skin penetration. It was shown that the 4?Hz-modulated low intensity 90-160?GHz MMW direct radiation and MMW-treated PS leads to on single neuron shrinkage, skin and brain tissue dehydration. On the basis of obtained data it was suggested that the cell bathing aqua medium serve as a target through which the NT effect of MMW on cell hydration is realized. The MMW-induced brain tissue dehydration can considering as consequence of MMW-induced skin water structural changes leading to unknown messenger formation able to modulate the brain cell hydration. The extrasensitivity of cell hydration to low intensity of MMW radiation allow to recommend cell hydration as a cellular marker for estimation of the NT biological effect of MMW on cells and organisms. 相似文献
69.
Falck-Zepeda J Yorobe J Husin BA Manalo A Lokollo E Ramon G Zambrano P Sutrisno 《GM crops & food》2012,3(1):52-59
Estimating the cost of compliance with biosafety regulations is important as it helps developers focus their investments in producer development. We provide estimates for the cost of compliance for a set of technologies in Indonesia, the Philippines and other countries. These costs vary from US $100,000 to 1.7 million. These are estimates of regulatory costs and do not include product development or deployment costs. Cost estimates need to be compared with potential gains when the technology is introduced in these countries and the gains in knowledge accumulate during the biosafety assessment process. Although the cost of compliance is important, time delays and uncertainty are even more important and may have an adverse impact on innovations reaching farmers. 相似文献
70.