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51.
Adhemar Longatto Filho Tiago Gil Oliveira Céline Pinheiro Marcos Brasilino de Carvalho Otávio Alberto Curioni Ana Maria da Cunha Mercante Fernando C Schmitt Gilka JF Gattás 《World journal of surgical oncology》2007,5(1):140
Background
Lymphatic vessels are major routes for metastasis in head and neck squamous cell carcinoma (HNSCC), but lymphatic endothelial cells (LECs) are difficult to recognize in tumor histological sections. D2-40 stains podoplanin, a molecule expressed in LECs, however, the potential prognostic usefulness of this molecule is not completely understood in HNSCC. We aimed to investigate the value of assessing peritumoral and intratumoral lymphatic vessel density (LVD) as prognostic marker for HNSCC.Methods
Thirty-one cases of HNSCC were stained for D2-40 and CD31. LVD and blood vessel density (BVD) were assessed by counting positive reactions in 10 hotspot areas at ×200 magnification.Results
D2-40 was specific for lymphatic vessels and did not stain blood vascular endothelial cells. LECs showed more tortuous and disorganized structure in intratumoral lymphatic vessels than in peritumoral ones. No statistical differences were observed between peritumoral-LVD and intratumoral-LVD or between peritumoral-BVD and intratumoral-BVD. Tumor D2-40 staining was positively associated with lymphatic vessel invasion (p = 0.011).Conclusion
LVD is a powerful marker for HNSCC prognosis. We found significant differences in peritumoral and intratumoral D2-40 immunoreactivity, which could have important implications in future therapeutic strategies and outcome evaluation.52.
Seth M Barribeau Ben M Sadd Louis du Plessis Mark JF Brown Severine D Buechel Kaat Cappelle James C Carolan Olivier Christiaens Thomas J Colgan Silvio Erler Jay Evans Sophie Helbing Elke Karaus H Michael G Lattorff Monika Marxer Ivan Meeus Kathrin N?pflin Jinzhi Niu Regula Schmid-Hempel Guy Smagghe Robert M Waterhouse Na Yu Evgeny M Zdobnov Paul Schmid-Hempel 《Genome biology》2015,16(1)
53.
T Yvanka de Soysa Allison Ulrich Timo Friedrich Danielle Pite Shannon L Compton Deborah Ok Rebecca L Bernardos Gerald B Downes Shizuka Hsieh Rachael Stein M Caterina Lagdameo Katherine Halvorsen Lydia-Rose Kesich Michael JF Barresi 《BMC biology》2012,10(1):1-25
Background
During nerve growth, cytoplasmic vesicles add new membrane preferentially to the growth cone located at the distal tip of extending axons. Growth cone membrane is also retrieved locally, and asymmetric retrieval facilitates membrane remodeling during growth cone repulsion by a chemorepellent gradient. Moreover, growth inhibitory factors can stimulate bulk membrane retrieval and induce growth cone collapse. Despite these functional insights, the processes mediating local membrane remodeling during axon extension remain poorly defined.Results
To investigate the spatial and temporal dynamics of membrane retrieval in actively extending growth cones, we have used a transient labeling and optical recording method that can resolve single vesicle events. Live-cell confocal imaging revealed rapid membrane retrieval by distinct endocytic modes based on spatial distribution in Xenopus spinal neuron growth cones. These modes include endocytic "hot-spots" triggered at the base of filopodia, at the lateral margins of lamellipodia, and along dorsal ridges of the growth cone. Additionally, waves of endocytosis were induced when individual filopodia detached from the substrate and fused with the growth cone dorsal surface or with other filopodia. Vesicle formation at sites of membrane remodeling by self-contact required F-actin polymerization. Moreover, bulk membrane retrieval by macroendocytosis correlated positively with the substrate-dependent rate of axon extension and required the function of Rho-family GTPases.Conclusions
This study provides insight into the dynamic membrane remodeling processes essential for nerve growth by identifying several distinct modes of rapid membrane retrieval in the growth cone during axon extension. We found that endocytic membrane retrieval is intensified at specific subdomains and may drive the dynamic membrane ruffling and re-absorption of filopodia and lamellipodia in actively extending growth cones. The findings offer a platform for determining the molecular mechanisms of distinct endocytic processes that may remodel the surface distribution of receptors, ion channels and other membrane-associated proteins locally to drive growth cone extension and chemotactic guidance. 相似文献54.
55.
Ashwini?S?Kucknoor Vasanthakrishna?Mundodi JF?AldereteEmail author 《BMC molecular biology》2005,6(1):5
Background
Trichomonosis, caused by Trichomonas vaginalis, is the number one, nonviral sexually transmitted infection that has adverse consequences for the health of women and children. The interaction of T. vaginalis with vaginal epithelial cells (VECs), a step preparatory to infection, is mediated in part by the prominent surface protein AP65. The bovine trichomonad, Tritrichomonas foetus, adheres poorly to human VECs. Thus, we established a transfection system for heterologous expression of the T. vaginalis AP65 in T. foetus, as an alternative approach to confirm adhesin function for this virulence factor. 相似文献56.
Vincens P; Buffat L; Andre C; Chevrolat JP; Boisvieux JF; Hazout S 《Bioinformatics (Oxford, England)》1998,14(8):715-725
MOTIVATION: Complete genomic sequences will become available in the future.
New methods to deal with very large sequences (sizes beyond 100 kb)
efficiently are required. One of the main aims of such work is to increase
our understanding of genome organization and evolution. This requires
studies of the locations of regions of similarity. RESULTS: We present here
a new tool, ASSIRC ('Accelerated Search for SImilarity Regions in
Chromosomes'), for finding regions of similarity in genomic sequences. The
method involves three steps: (i) identification of short exact chains of
fixed size, called 'seeds', common to both sequences, using hashing
functions; (ii) extension of these seeds into putative regions of
similarity by a 'random walk' procedure; (iii) final selection of regions
of similarity by assessing alignments of the putative sequences. We used
simulations to estimate the proportion of regions of similarity not
detected for particular region sizes, base identity proportions and seed
sizes. This approach can be tailored to the user's specifications. We
looked for regions of similarity between two yeast chromosomes (V and IX).
The efficiency of the approach was compared to those of conventional
programs BLAST and FASTA, by assessing CPU time required and the regions of
similarity found for the same data set. AVAILABILITY: Source programs are
freely available at the following address: ftp://ftp.biologie.ens.
fr/pub/molbio/assirc.tar.gz CONTACT: vincens@biologie.ens.fr,
hazout@urbb.jussieu.fr
相似文献
57.
Saskia I. Johanns Richard G. Gantin Bawoubadi Wangala Kossi Komlan Wemboo A. Halatoko Meba Banla Potchoziou Karabou Adrian JF Luty Hartwig Schulz-Key Carsten Khler Peter T. Soboslay 《PLoS neglected tropical diseases》2022,16(5)
BackgroundAnnual mass drug administrations (MDA) of ivermectin will strongly reduce Onchocerca volvulus microfilariae (mf) in the skin and in the onchocerciasis patients’ eyes. Ivermectin treatment will also affect the expression of immunity in patients, such that activated immune defenses may help control and contribute to clearance of mf of O. volvulus. Longitudinal surveys are a prerequisite to determining the impact of ivermectin on the status of anti-parasite immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist.Methodology/Principal findingsOnchocerciasis patients were treated annually with ivermectin and their Onchocerca volvulus antigen (OvAg) specific IgG and cellular responses were investigated before and at 30 years post initial ivermectin treatment (30yPT).Repeated annual ivermectin treatments eliminated persisting O. volvulus microfilariae (mf) from the skin of patients and abrogated patent infections. The OvAg-specific IgG1 and IgG4 responses were diminished at 30yPT to the levels observed in endemic controls. Prior to starting ivermectin treatment, OvAg-induced cellular productions of IL-10, IFN-γ, CCL13, CCL17 and CCL18 were low in patients, and at 30yPT, cellular cytokine and chemokine responses increased to the levels observed in endemic controls. In contrast, mitogen(PHA)- induced IL-10, IFN-γ, CCL17 and CCL18 cellular production was diminished. This divergent response profile thus revealed increased parasite antigen-specific but reduced polyclonal cellular responsiveness in patients. The transmission of O. volvulus continued at the patients’ location in the Mô river basin in central Togo 2018 and 2019 when 0.58% and 0.45%, respectively, of Simulium damnosum s.l. vector blackflies carried O. volvulus infections.Conclusions/SignificanceRepeated annual ivermectin treatment of onchocerciasis patients durably inhibited their patent O. volvulus infections despite ongoing low-level parasite transmission in the study area. Repeated MDA with ivermectin affects the expression of immunity in patients. O. volvulus parasite-specific antibody levels diminished to levels seen in infection-free endemic controls. With low antibody levels, antibody-dependent cellular cytotoxic responses against tissue-dwelling O. volvulus larvae will weaken. O. volvulus antigen inducible cytokine and chemokine production increased in treated mf-negative patients, while their innate responsiveness to mitogen declined. Such lower innate responsiveness in elderly patients could contribute to reduced adaptive immune responses to parasite infections and vaccines. On the other hand, increased specific cellular chemokine responses in mf-negative onchocerciasis patients could reflect effector cell activation against tissue invasive larval stages of O. volvulus. The annual Simulium damnosum s.l. biting rate observed in the Mô river basin was similar to levels prior to initiation of MDA with ivermectin, and the positive rtPCR results reported here confirm ongoing O. volvulus transmission. 相似文献
58.
JP Valde LG Lawson A Lindberg JF Agger H Saloniemi O Østerås 《Acta veterinaria Scandinavica》2004,45(4):201-210
Data from the national dairy cow recording systems during 1997 were used to calculate lactation-specific cumulative risk of mastitis treatments and cumulative risk of removal from the herds in Denmark, Finland Norway and Sweden. Sweden had the lowest risk of recorded mastitis treatments during 305 days of lactation and Norway had the highest risk. The incidence risk of recorded mastitis treatments during 305 days of lactation in Denmark, Finland, Norway and Sweden was 0.177, 0.139, 0.215 and 0.127 for first parity cows and 0.228, 0.215, 0.358 and 0.204 for parities higher than three, respectively. The risk of a first parity cow being treated for mastitis was almost 3 times higher at calving in Norway than in Sweden. The period with the highest risk for mastitis treatments was from 2 days before calving until 14 days after calving and the highest risk for removal was from calving to 10 days after calving in all countries.The study clearly demonstrated differences in bovine mastitis treatment patterns among the Nordic countries. The most important findings were the differences in treatment risks during different lactations within each country, as well as differences in strategies with respect to the time during lactation mastitis was treated. 相似文献
59.
We previously concluded that the Kv2.1 K(+) channel inactivates preferentially from partially activated closed states. We report here that the Kv3.1 channel also exhibits two key features of this inactivation mechanism: a U-shaped voltage dependence measured at 10 s and stronger inactivation with repetitive pulses than with a single long depolarization. More surprisingly, slow inactivation of the Kv1 Shaker K(+) channel (Shaker B Delta 6--46) also has a U-shaped voltage dependence for 10-s depolarizations. The time and voltage dependence of recovery from inactivation reveals two distinct components for Shaker. Strong depolarizations favor inactivation that is reduced by K(o)(+) or by partial block by TEA(o), as previously reported for slow inactivation of Shaker. However, depolarizations near 0 mV favor inactivation that recovers rapidly, with strong voltage dependence (as for Kv2.1 and 3.1). The fraction of channels that recover rapidly is increased in TEA(o) or high K(o)(+). We introduce the term U-type inactivation for the mechanism that is dominant in Kv2.1 and Kv3.1. U-type inactivation also makes a major but previously unrecognized contribution to slow inactivation of Shaker. 相似文献
60.
Penelope R Whitehorn Matthew C Tinsley Mark JF Brown Ben Darvill Dave Goulson 《BMC evolutionary biology》2009,9(1):152-9