bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tumour necrosis factor-αconverting enzyme (TACE) activity in human colonic epithelial cells
Authors: KIRKEGAARD T , PEDERSEN G , SAERMARK T , BRYNSKOV J 
Published: December 2003

SUMMARYTumour necrosis factor (TNF)-α converting enzyme (TACE) releases biologically active, soluble TNF-α from transmembrane pro-TNF-α and has attracted interest as a specific therapeutic target in inflammatory bowel disease (IBD). Strong immunoreactivity for TACE protein was demonstrated recently in human colonic epithelium, but the function is unknown. We investigated if human colonic epithelial cells express functional TACE activity and how TACE expression is regulated in response to cytokine stimulation. TACE and TNF-α mRNA and protein expression were measured in HT-29 and DLD-1 colonic epithelial cells by reverse-transcription polymerase chain reaction, western blotting or enzyme-linked immunosorbent assay. Monocytic THP-1 cells served as positive control. Functional TACE activity was identified and quantified in detergent extracts of cell lines and freshly isolated colonocytes from 14 IBD patients and five controls by a hydrolysis assay using an oligopeptide spanning the cleavage site in pro-TNF-α. HT-29 and DLD-1 cells spontaneously expressed TACE mRNA and the active form of TACE protein at levels similar to those of monocytic cells. Functional TACE activity was demonstrated in all cell lines and in cells of controls or IBD patients irrespective of disease activity. TACE mRNA expression and functional activity remained unchanged in cell lines after stimulation with TNF-α despite clear induction of TNF-α mRNA expression and release of soluble TNF-α protein. The release of soluble TNF-α protein was almost completely abolished by CH4474, a synthetic TACE inhibitor. We conclude that functional TACE activity is constitutively expressed in human colonic epithelial cells and responsible for processing of the mature, soluble form of TNF-α in response to cytokine stimulation.
Response to simulated climatic change in an alpine and subarctic pollen‐risk strategist, Silene acaulis
Authors: ALATALO J.M. , TOTLAND Ø. 
Published: December 2003

The aim of this study was to test if early flowering species respond with increased seed production to climate warming as is predicted for late‐flowering seed‐risk strategists. Experimental climate warming of about 3°C was applied to two populations of the cushion‐forming plant Silene acaulis (L.) Jacq. The experiment was run at one subarctic site and one alpine site for 2 years and 1 year, respectively, using open‐top chambers (OTC).The 2‐year temperature enhancement at the subarctic site had a marked effect on the flowering phenology. Cushions inside the OTC started flowering substantially earlier than control cushions. Both the male and female phases developed faster in the OTCs, and maturation of capsules occurred earlier. The cushions also responded positively in reproductive terms and produced more mature seeds and had a higher seed/ovule ratio. After 1 year temperature enhancement at the alpine site there was a weak trend for earlier flowering, but there was no significant difference in seed production or seed/ovule ratio.
Response to experimental warming in a population of Papaver radicatum in Greenland
Authors: MØLGAARD P. , CHRISTENSEN K. 
Published: December 2003

In an attempt to simulate the effect of a global climatic change, temperature manipulations were carried out in a natural population of Papaver radicatum from a low arctic area on Disko Island, West Greenland. The manipulations were carried out by means of ITEX corners, which are angular plexiglass screens placed around individual plants. The corners were placed with openings towards four directions and different microclimatic conditions were obtained. The corners increase the summer temperature to different degrees in the four directions. In addition they are windscreens and eventually accumulate snow, dependent on the wind directions.Dataloggers in a set of corners measured temperatures at the end of one growing season and at the beginning of the next. Spring was delayed in all corners due to increased snow cover duration, especially in those facing East and North. Nevertheless, temperatures were increased in the corners during the season, and highest temperature sums were obtained in those facing South and West. No temperature increase was found in the North‐facing corners.No effect was seen on the plants the first year after application of the ITEX corners. In the second year an increased biomass was observed in corners facing West and South in accordance with the higher temperatures experienced in these directions. In the third biomass year plants in corners facing West decreased and those facing North slightly increased compared to previous years. After 4 years plants in corners facing West, South and East had attained significantly higher biomass than the control plants and the plants in corners facing North.An earlier onset of flowering was seen in the corners compared to control, and South‐facing corners had more flowers. An early onset of the growth period is an advantage to flowering, more so than increased temperatures during the season. Flowering was prolonged in the corners compared to controls, but there was a higher risk of frost damage to the flowers in the corners.
Exsertion, elongation, and senescence of leaves of Eriophorum vaginatum and Carex bigelowii in Northern Alaska
Authors: SHAVER G.R. , LAUNDRE J. 
Published: December 2003

The seasonal patterns of leaf exsertion, elongation, and senescence were described and compared for two of the most abundant graminoid species of Alaskan moist tussock tundra, Eriophorum vaginatum and Carex bigelowii. In addition the responses of both species to NPK fertilizer and to variation in site fertility (water track vs. non‐track areas) were also assayed and compared. The research was done over two full growing seasons at two sites near Toolik Lake, Alaska, where other aspects of the ecology of both species have been the subject of intensive and ongoing research.Both species showed the typical graminoid pattern of sequential leaf growth, in which the exsertion and elongation of new leaves is coincident with the senescence of old leaves. However, the rates of these processes were much slower and steadier in Eriophorum than in Carex, with much greater overlap in the life histories of individual leaf cohorts. The total and green leaf lengths of whole tillers in Eriophorum were also less variable over the entire year than in Carex. The conclusion is that leaf growth in Carex should depend more on external storage of carbon and nutrients than Eriophorum, with a much greater seasonal variation in demands on storage and retranslocation to and from leaves.The effects of fertilizer and the water track on leaf growth dynamics and turnover rates were largely nonsignificant, despite major effects on total tiller size and productivity. This is in contrast to previous research on evergreen leaf dynamics, but similar to results of previous research on overall production and biomass regulation in Eriophorum. It is concluded that the graminoid response to increased nutrient availability in the Arctic is to dilute the greater amounts of nutrient uptake by greater growth, so that nearly the same metabolic homeostasis is achieved as under low nutrient availability, but at a higher biomass.
Vegetation dynamics in central Africa since 18,000 yr BP: pollen records from the interlacustrine highlands of Burundi, Rwanda and western Uganda
Authors: Jolly Dominique , Taylor David , Marchant Robert , Hamilton Alan , Bonnefille Raymonde , Buchet Guillaume , Riollet Guy 
Published: December 2003

A standardized analysis of palaeoecological data, in the form of six pollen sequences and forty‐ four radiocarbon ages, has permitted a region‐wide reconstruction of Late Quaternary vegetation dynamics for the interlacustrine highlands of central Africa.A landscape widely dominated by ericaceous scrub and grasslands, but also supporting sparse patches of open‐canopied montane forest, possibly in those areas with a topography most favourable to the growth of trees, is indicated for the last glacial maximum of 18,000 yr bp. Major expansions in the extent of upper altitudinal forms of montane forest occurred from around 12,500 yr bp, while lower moist montane forest—the expected climax for much of the region today—did not become prominent until 11,000 yr bp to 10,000 yr bp. From the palaeoecological evidence at least, it appears that the major east Central forest refuge, proposed by some workers on the basis of current species’ distribution patterns, did not extend to the eastern flanks of the Albertine Rift.A late glacial–early Holocene transition is only fully chronicled in two of the sites. However, it appears that the expansion of lower montane forest had a time‐transgressive pattern across the region, and was not simply from low to high altitude. The composition of forests during the early Holocene appears to have been different to that in the later stages of the present interglacial, as taxa presently associated with wetter and/or more open forest types were much more common. Pollen data also indicate that higher altitude parts of the interlacustrine highlands were more attractive to the earliest (possibly Bantu‐speaking) farmers and metal‐workers. There is evidence of wide‐spread forest clearance around the beginning of the present millennium, possibly as a result of substantial changes in socio‐economic conditions, and patterns of settlement, associated with the onset of the Late Iron Age.
High‐pressure freezing of epithelial cells on sapphire coverslips
Authors: Reipert S. , Fischer I. , Wiche G. 
Published: December 2003

SummaryRapid freezing of cell monolayers at ambient pressure is limited regarding the thickness of ice crystal damage‐free freezing. The specific freezing conditions of the cells under investigation are decisive for the success of such methods. Improved reproducibility of results could be expected by cryoimmobilization at high pressure because this achieves a greater thickness of adequate freezing. In a novel approach, we tested the suitability of sapphire discs as cell substrata for high‐pressure freezing. Frozen samples on sapphire were subjected to freeze‐substitution while in the same flat sample holders as used for high‐pressure freezing. We obtained cells that displayed an excellent preservation of fine structure. Because sapphire is a tissue culture substratum suitable for light microscopy, its use in combination with high‐pressure freezing could become a powerful tool in correlative studies of cell dynamics at light and electron microscopic levels.
A recombinant 31.5 kDa keratinase and a crude exo‐antigen fromMicrosporum canisfail to protect against a homologous experimental infection in guinea pigs
Authors: Descamps Frédéric F. , Brouta Frédéric , Vermout Sandy M. , Willame Corinne , Losson Bertrand J. , Mignon Bernard R. 
Published: December 2003

Abstract AMicrosporum canisrecombinant 31.5 kDa keratinase and aM. caniscrude exo‐antigen were tested as vaccines in an experimental infection model in guinea pigs. Animals were vaccinated subcutaneously three times at two‐week intervals with either the keratinase, the exo‐antigen or the adjuvant alone. Cutaneous challenge was performed blindly. Both humoral and cellular‐specific immune responses toM. canisantigens were evaluated every 14 days, while a blind evaluation of clinical lesion development and fungal persistency in skin were monitored weekly. Vaccination induced very high and significant (P < 0.01) antibody responses towards both antigens. High cell‐mediated immune responses to both immunogens were also induced by vaccination. After challenge, however, scores reflecting the severity of dermatophytic lesions did not differ significantly between vaccinated and control groups at any time after challenge. These results suggest that, in the guinea pig, the induction of specific immune responses against theM. canis‐secreted antigens used in this study are not protective against challenge exposure.
Feline pemphigus foliaceus: a retrospective analysis of 57 cases
Authors: Preziosi Diane E. , Goldschmidt Michael H. , Greek Jean S. , Jeffers Jim G. , Shanley Kevin S. , Drobatz Kenneth , Mauldin Elizabeth A. 
Published: December 2003

Abstract Fifty‐seven cases of feline pemphigus foliaceus were identified from biopsy specimens submitted to University of Pennsylvania School of Veterinary Medicine's Laboratory of Pathology and Toxicology by veterinary dermatologists from 1991 to 2002. Age at onset ranged from less than 1 year to 17 years; median 5 years. Eighty per cent of cats were reported to have been pruritic. At the time of biopsy, the distribution of lesions varied, but included some combination of face/head, paws, dorsum or ventrum and consisted of crusts, erosions, scale and alopecia. The histological features of 208 biopsy specimens were reviewed and included the following. Acantholytic cells were found in large numbers in both intact and degenerating pustules in most cases. Mast cells were found in the dermal infiltrate more often than reported previously. Seventeen cases were receiving corticosteroids at the time of biopsy; reducing the percentage of diagnostic biopsies per case. Forty‐four cases were followed for 1–54 months (median 9 months). Triamcinolone was more successful at inducing remission without significant adverse effects than prednisone or prednisone in combination with chlorambucil. Only 4/44 cats died from their disease or therapy during the study period.
Evaluation of intravenous fluorescein in intradermal allergy testing in psittacines
Authors: Nett Claudia S. , Hosgood Giselle , Heatley J. Jill , Foil Carol S. , Tully Thomas N. 
Published: December 2003

Abstract  This study was designed to improve the clinical feasibility of intradermal skin testing of psittacine birds using intravenous fluorescein stain. Twenty‐five healthy, anaesthetized Hispaniolan Amazon parrots (Amazona ventralis) were injected intravenously with 10 mg kg−1 fluorescein–sodium 1% followed by intradermal injections of 0.02 mL phosphate‐buffered saline, histamine phosphate (1:100 000 w/v) and codeine phosphate (1:100 000 w/v) at the sternal apteria. Wheal diameters of reaction sites were measured grossly and under illumination with a Wood's lamp after 5 and 10 min. Fluorescence‐enhanced injection sites were scored between 0 and 2, with 0 equivalent to normal skin and 2 equivalent to a plucked feather follicle. The presence of a fluorescent halo around intradermal injections was also recorded. Under Wood's light illumination at 10 min, histamine and saline were evaluated as positive and negative controls, respectively, based on a positive test having a halo and a score of 2. Sensitivity and specificity were each 76% for halo, 84 and 42% for score and 64 and 77% for combination of score and halo, respectively. Further, mean histamine reactions were significantly larger than codeine phosphate and saline (8.8 ± 0.4 mm; 7.2 ± 0.3 mm; 5.9 ± 0.6 mm); however, this finding was not consistent in individual birds. Wheal size, halo presence and score were affected by site location independent from the injected compound. Intravenous fluorescein improved the readability of avian skin tests; however, the compounds tested raised inconsistent reactions in wheal size, score or halo presence. The compound‐independent site effect raises concern on the validity of avian skin testing and warrants investigation of other techniques such as in vitro allergy testing. Based on our findings, intradermal allergy testing in psittacines with or without fluorescein is unreliable and cannot be recommended for practical clinical use.
Feline plasma cell pododermatitis: a study of 8 cases
Authors: Dias Pereira Patrícia , Faustino Augusto M. R. 
Published: December 2003

Abstract Eight cases of feline plasma cell pododermatitis, collected over a 3‐year period, were studied using histological (haematoxylin and eosin), histochemical (methyl green–pyronin) and immunohistochemical (antibody against lambda light chains of immunoglobulins) techniques. No sex, breed or age predisposition, or paw predilection was observed. The disease began as a swelling of the footpads, followed by ulceration. Histologically, lesions were characterized by the presence of a large number of plasma cells in a predominantly perivascular pattern. Binucleated plasma cells and mitotic figures were observed. Clinical follow‐up for over 1 year revealed total remission of the lesions both after glucocorticoid therapy in four cases, and total surgical excision in two animals. Follow‐up studies were not possible in one case.
Zur funktionellen Morphologie der Dickdarm‐Mukosa von Rind (Bos primigenius f. taurus), Schaf (Ovis ammon f. aries) und Ziege (Capra aegagrus f. hircus)*
Authors: Wille K.‐H 
Published: December 2003

On the functional morphology of the large intestinal mucosa of the ox (

Bos primigenius

f. taurus), sheep (

Ovis ammon

f. aries) and goat (

Capra aegagrus

f. hircus) The mucous membrane of the large intestine of the ox, sheep and goat was studied using light and electron microscopy. The surface epithelium possesses the well‐known complement of organelles with a conspicuous number of mitochondria as a source of energy for absorptive activities. Occasionally, brush cells are found in the epithelium; the functional significance of this type of cell is still under discussion. In the present material, electron‐lucid spheroids (diameter: 45 × 35 nm), which tend to fuse, appear in the supranuclearly located osmiophilic granules. The structure and appearance of the epithelium cells in the crypts of these species correspond to previous descriptions in other mammals. In the epithelial cells of the deep glandular region, dense accumulations of mainly rounded granules (diameter up to 400 nm) are found apically in the cytoplasm. Their functional significance is still under discussion. Acid phosphatase activity, as a marker enzyme for lysosomes, points to degenerative processes in connection with the physiological death of enterocytes. In contrast, the negative alkaline phosphatase reaction indicates that, according to our findings, the epithelial transport of substances in the large intestine of ruminants – in principle contrary to the situation in the small intestinal enterocytes – occurs without the aid of this enzyme. The demonstrated ATPase activity on the other hand, is related to a primary active ion transport linked with membrane exchange of non‐electrolytes in connection with transepithelial events of absorption and secretion in the large intestine.
Konstruktionsprinzipien an der Vorder‐ und Hinterpfote der Hauskatze (Felis catus). III. Mitteilung: Muskulatur
Authors: Vollmerhaus B , Roos H 
Published: December 2003

Principles of construction in the forepaw and hindpaw of the domestic cat (

Felis catus

). III: Musculature With regard to muscular mass and inner structure, the muscles of the forepaw and hindpaw of the domestic cat are grouped functionally, compared and evaluated. A high degree of functional adaptation is present in these muscles, for example in the passive locomotion apparatus of the paws. The domestic cat is not a ‘running animal’ like other domestic mammals. Also, in domestication it has preserved a strongly individual way of life and has remained a quick, ambushing hunter and climber on the run. Hence its forepaw is a flexible guiding and gripping apparatus, while its hindpaw provides stability for sprinting and non‐skid pushing. The partly re‐interpreted functions of the muscles are described and listed in four tables.
The nutrient status of Nong Han, a shallow tropical lake in north‐eastern Thailand: Spatial and temporal variations
Authors: Settacharnwit Surattana , Buckney Rodney T. , Lim Richard P. 
Published: December 2003

AbstractSpatial and temporal patterns of nutrient (nitrate‐N, ammonia‐N and phosphate) concentrations in the Nong Han water column were examined during the dry (January – May) and wet (August – October) seasons in 2001. Low nitrate‐N concentrations in the water were common. High ammonia‐N concentrations were found on all occasions, but particularly in the early wet season. Phosphate concentrations in the water column were very high. The very low nitrate‐N and low ammonia‐N concentrations (in early dry, late dry and late wet seasons), and low phosphate concentrations (in the early dry season) were attributed to assimilation by dense stands of macrophytes, in particular submerged types during the low water season. Additionally, higher nitrate‐N concentrations found in the late wet season might be related to increases in the water level and nitrification activity at the sediment–water interface. The very high ammonia‐N and phosphate concentrations in the water during the early wet season possibly reflect run‐off from agricultural areas in the Nong Han catchment and the regeneration of ammonia‐N and phosphate from recently degraded organic matter (particularly decaying macrophytes) in the surface sediment layer. Also, higher phosphate concentrations in the bottom water of most samples in the late dry and late wet seasons were attributed to temporary anaerobic conditions caused by submerged macrophyte decomposition and aerobic conditions, respectively. These hypotheses are consistent with dissolved oxygen and pH conditions found in both seasons.
A fish kill event, hypoxia and other limnological impacts associated with early wet season flow into a lake on the Mary River floodplain, tropical northern Australia
Authors: Townsend Simon A. , Edwards C. A. 
Published: December 2003

AbstractThe Mary River, in the Australian wet/dry tropics, flows seasonally to inundate a coastal floodplain. In the dry season, the river reduces to a series of disconnected lakes located along the main river channel. This paper examines the impact of riverine inflow, at the beginning of the wet season, on the limnology of Shady Camp Lake, and addresses broader water quality management issues. The first wet season flow of Mary River carried a high biological oxygen demand that reduced the lake's oxygen concentration. The resulting hypoxic conditions prompted fish avoidance behaviour and caused the death of at least 200 fish. There is no evidence of any direct anthropogenic pollution causing the event. After reaching near anoxic conditions, dissolved oxygen concentrations recovered several weeks later, although they remained low. The water quality of the Mary River was characterized by an initial pulse of water with high concentrations of organic carbon, suspended particulate material, colour, total nitrogen and total phosphorus. Phytoplankton biomass, measured as chlorophyll a, did not increase because of nitrogen limitation attributed to low nitrate and ammonia concentrations in the inflow waters. The low concentrations of available nitrogen were probably a result of denitrification, which would have been enhanced by the warm temperatures and low oxygen concentrations. The oxygen sag in Shady Camp Lake caused by the inflow of the Mary River exemplifies the vulnerability of floodplain channel lakes to riverine waters and underscores the need to manage catchment practices to minimize the concentration of labile organic material in the river and its associated oxygen demand.