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Aditya K. Manek Maud C. O. Ferrari Robyn J. Pollock Daniel Vicente Lynn P. Weber Douglas P. Chivers 《PloS one》2013,8(3)
Many prey fishes possess large club cells in their epidermis. The role of these cells has garnered considerable attention from evolutionary ecologists. These cells likely form part of the innate immune system of fishes, however, they also have an alarm function, releasing chemical cues that serve to warn nearby conspecifics of danger. Experiments aimed at understanding the selection pressures leading to the evolution of these cells have been hampered by a surprisingly large intraspecific variation in epidermal club cell (ECC) investment. The goal of our current work was to explore the magnitude and nature of this variation in ECC investment. In a field survey, we documented large differences in ECC investment both within and between several populations of minnows. We then tested whether we could experimentally reduce variation in mean ECC number by raising fish under standard laboratory conditions for 4 weeks. Fish from different populations responded very differently to being held under standard laboratory conditions; some populations showed an increase in ECC investment while others remained unchanged. More importantly, we found some evidence that we could reduce within population variation in ECC investment through time, but could not reduce among-population variation in mean ECC investment. Given the large variation we observed in wild fish and our limited ability to converge mean cell number by holding the fish under standard conditions, we caution that future studies may be hard pressed to find subtle effects of various experimental manipulations; this will make elucidating the selection pressures leading to the evolution of the cells challenging. 相似文献
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Roseane Borner Jo?o Bento-Torres Diego RV Souza Danyelle B Sadala Nonata Trevia José Augusto Farias Nara Lins Aline Passos Amanda Quintairos José Ant?nio Diniz Victor Hugh Perry Pedro Fernando Vasconcelos Colm Cunningham Cristovam W Pican?o-Diniz 《朊病毒》2011,5(3):215-227
Behavioral and neuropathological changes have been widely investigated in murine prion disease but stereological based unbiased estimates of key neuropathological features have not been carried out. After injections of ME7 infected (ME7) or normal brain homogenates (NBH) into dorsal CA1 of albino Swiss mice and C57BL6, we assessed behavioral changes on hippocampal-dependent tasks. We also estimated by optical fractionator at 15 and 18 weeks post-injections (w.p.i.) the total number of neurons, reactive astrocytes, activated microglia and perineuronal nets (PN) in the polymorphic layer of dentate gyrus (PolDG), CA1 and septum in albino Swiss mice. On average, early behavioral changes in albino Swiss mice start four weeks later than in C57BL6. Cluster and discriminant analysis of behavioral data in albino Swiss mice revealed that four of nine subjects start to change their behavior at 12 w.p.i. and reach terminal stage at 22 w.p.i and the remaining subjects start at 22 w.p.i. and reach terminal stage at 26 w.p.i. Biotinylated dextran-amine BDA-tracer experiments in mossy fiber pathway confirmed axonal degeneration and stereological data showed that early astrocytosis, microgliosis and reduction in the perineuronal nets are independent of a change in the number of neuronal cell bodies. Statistical analysis revealed that the septal region had greater levels of neuroinflammation and extracellular matrix damage than CA1. This stereological and multivariate analysis at early stages of disease in an outbred model of prion disease provided new insights connecting behavioral changes and neuroinflammation and seems to be important to understand the mechanisms of prion disease progression.Key words: prion disease, optical fractionator, neuropathology, behavioral changes, albino Swiss mice 相似文献
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S. Manek 《Cytopathology》2012,23(3):146-149
S. Manek The pathology clinic – pathologists should see patients This invited review describes why and how a pathologist should talk to patients in order to enhance the patient care pathway. The pathologist–patient interaction should become a natural extension to multidisciplinary team decision making, and also become the forum in which patients are helped to understand important aspects of their conditions and the pathological basis for their treatment plans. There is a vast amount of information available through the internet and to digest this can be a difficult process for a patient who is already having to cope with a medical condition. The pathologist is often best placed to sieve through this information and offer the patient the relevant detail necessary to understand the condition and the management pathway. Pathologists can provide up‐to‐date, simple information about malignant and even certain significant benign conditions, and they can do this with the help of several pictorial tools. In this way, the pathologist becomes an even more active member of a clinical team and helps both clinicians and patients to deal with illnesses in a novel way hitherto not considered. 相似文献
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Ian PG Marshall Dusty RV Berggren Mohammad F Azizian Luke C Burow Lewis Semprini Alfred M Spormann 《The ISME journal》2012,6(4):814-826
We developed a broad-ranging method for identifying key hydrogen-producing and consuming microorganisms through analysis of hydrogenase gene content and expression in complex anaerobic microbial communities. The method is based on a tiling hydrogenase gene oligonucleotide DNA microarray (Hydrogenase Chip), which implements a high number of probes per gene by tiling probe sequences across genes of interest at 1.67 × –2 × coverage. This design favors the avoidance of false positive gene identification in samples of DNA or RNA extracted from complex microbial communities. We applied this technique to interrogate interspecies hydrogen transfer in complex communities in (i) lab-scale reductive dehalogenating microcosms enabling us to delineate key H2-consuming microorganisms, and (ii) hydrogen-generating microbial mats where we found evidence for significant H2 production by cyanobacteria. Independent quantitative PCR analysis on selected hydrogenase genes showed that this Hydrogenase Chip technique is semiquantitative. We also determined that as microbial community complexity increases, specificity must be traded for sensitivity in analyzing data from tiling DNA microarrays. 相似文献
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LILIAN JÄRVEKÜLG JÜRI SõBER RIIVO SINIJÄRV INDREK TOOTS MART SAARMA 《The Annals of applied biology》1989,114(2):279-291
Mouse monoclonal antibodies (MAbs) specific for potato virus M (PVM) were prepared and the properties of three of them were studied. MAb M4C1 is IgG2b, it binds with high affinity to PVM coat protein, to purified virus preparations and recognises PVM in infected potato leaves and tubers. MAb M6D5 is IgG2a and also reacts with PVM coat protein, purified PVM and with PVM in potato leaf and tuber extracts. In double-antibody sandwich ELISA (DAS ELISA) MAbs M4C1 and M6D5 reacted with all 17 PVM isolates tested. MAb M7 is IgG2b and recognises PVM only in indirect dot ELISA on nitrocellulose filters and viral coat protein on Western blots. MAbs against PVM were used as capture antibodies and europium-labelled MAbs as conjugates in time-resolved fluoroimmunoassay (EuTRFIA). The standard EuTRFIA curve of PVM detection is approximately linear over a range of PVM concentrations from 0.5 ng/ml to 1000 ng/ml. The lowest PVM concentration detectable in EuTRFIA was 0.5 ng/ml and correspondingly 6 ng/ml in DAS ELISA. The use of the europium chelate label allows PVM detection in potato leaf and tuber sap at dilutions greater than 10--4 with very low background fluorescence. EuTRFIA with MAbs, with either one or two incubations is about 10–20 times more sensitive for PVM detection than is DAS ELISA. PVM and PVX, mixed with healthy potato tuber sap, were simultaneously tested in a single sample at concentrations lower than 10 ng/ml by double-label TRFIA using europium-labelled MAbs to PVM and samarium-labelled MAbs to PVX. 相似文献
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The differential diagnosis of fibroadenomas vs phyllodes tumours by fine needle aspiration (FNA) cytology is not possible in the majority of cases. The present study aims to look at common and dissimilar features to allow differentiation, if possible. We reviewed the FNA findings of 18 histologically proven phyllodes tumours and 18 fibroadenomas, checking in each case the epithelial features, the stromal features, and any atypia. Using a semi-quantitative score assessed by two observers we were able in most cases to distinguish a phyllodes tumour from a fibroadenoma. The most important criteria were larger stromal fragments, numerous plump stromal bare nuclei, and the higher ratio of stromal bare nuclei to epithelial bare nuclei in phyllodes tumours. In the present study, an original diagnosis of phyllodes tumour was made in 7/18 (38.9%) cases but with our criteria this could be improved to 15/18 (83.3%) cases. Therefore, the presence of specific stromal features in a dimorphic cellular pattern should suggest the correct diagnosis and differentiate its appearance from a cellular fibroadenoma. 相似文献
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Timothy McPherson Rahul V. Manek William Kolling Sihui Long Tonglei Li 《AAPS PharmSciTech》2010,11(2):720-728
1,3-dipropyl-8-cyclopentylxanthine (CPX) has been shown to stimulate in vitro CFTR activity in ∆F508 cells. Data from a phase I study demonstrated erratic bioavailability and no measurable clinical response
to oral CPX. One cause for its poor bioavailability may have been dissolution rate limited absorption, but there is little
published physicochemical data on which to base an analysis. The objective of this study was to determine the solubility and
solid-state characteristics of CPX. CPX is a weak acid with pKa of 9.83 and water solubility at pH 7.0 of 15.6 μM. Both laureth-23
and poloxamer 407 increased the apparent water solubility linearly with increasing concentrations. CPX exists in two crystal
forms, one of which (form II) has been solved. Form II is a triclinic crystal with space group P1 and calculated density of
1.278 g/cm3. X-ray powder diffraction and differential scanning calorimetry studies (DSC) indicated that CPX crystals prepared at room
temperature were mixtures of forms I and II. DSC results indicated a melting point of approximately 195°C for form I and 198°C
for form II. Thermogravimetric analysis indicated no solvent loss upon heating. Dynamic water vapor sorption data indicated
no significant water uptake by CPX up to 90% RH. Analysis of the data indicates that CPX may not be amenable to traditional
formulation approaches for oral delivery. 相似文献
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Ananworanich J Schuetz A Vandergeeten C Sereti I de Souza M Rerknimitr R Dewar R Marovich M van Griensven F Sekaly R Pinyakorn S Phanuphak N Trichavaroj R Rutvisuttinunt W Chomchey N Paris R Peel S Valcour V Maldarelli F Chomont N Michael N Phanuphak P Kim JH;RV/SEARCH Study Group 《PloS one》2012,7(3):e33948