2,853 research outputs found
Pericyte deficiencies lead to aberrant tumor vascularizaton in the brain of the NG2 null mouse.
No full textTightly regulated crosstalk between endothelial cells and pericytes is required for formation and maintenance of functional blood vessels. When the NG2 proteoglycan is absent from pericyte surfaces, vascularization of syngeneic tumors growing in the C57B1/6 mouse brain is aberrant in several respects, resulting in retardation of tumor progression. In the NG2 null mouse brain, pericyte investment of the tumor vascular endothelium is reduced, causing deficiencies in both pericyte and endothelial cell maturation, as well as reduced basal lamina assembly. While part of this deficit may be due to the previously-identified role of NG2 in 51 integrin-dependent periyte/endothelial cell crosstalk, the ablation of NG2 also appears responsible for loss of collagen VI anchorage, in turn leading to reduced collagen IV deposition. Poor functionality of tumor vessels in NG2 null brain is reflected by reduced vessel patency and increased vessel leakiness, resulting in large increases in tumor hypoxia. These findings demonstrate the importance of NG2-dependent pericyte/endothelial cell interaction in the development and maturation of tumor blood vessels, identifying NG2 as a potential target for anti-angiogenic cancer therapy
Disappearance of Vela or Imig in spleen of 20-wk (left) or 5-wk (right) 9 V/null mice.
No full text<p>GCase activities in spleen were determined from 20 min to 42 h post-injection and represented as fold of WT (WT = 1) as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010750#pone-0010750-g002" target="_blank">Figure 2</a>. The disappearances of Vela or Imig activities were plotted as fold WT (activity panels) or from the 20-min (20-wk) or 40-min (5-wk) peak values (% peak activity panels). The GCase activities in spleen from saline-injected mice were 8.1% (SE = ±0.017) of WT (<b>X</b>, solid line at the bottom of top panels). Disappearances of Vela or Imig proteins (CRIM panels) up to 42 h post-injection were analyzed by immunoblots as per <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0010750#pone-0010750-g002" target="_blank">Figure 2</a>.</p
Behavior during transition differs for cows diagnosed with claw horn lesions in mid lactation
No full textClaw horn lesions, including sole hemorrhages and sole ulcers, are a major cause of lameness in dairy cattle. These lesions often develop in the weeks around calving and become visible 8 to 12 wk later. The aim was to determine whether cows that are diagnosed with claw horn lesions several weeks after calving behave differently during the calving period when the lesions are thought to first develop. The claws of 26 multiparous Holstein dairy cows were scored for sole hemorrhage severity and presence of sole ulcers 2 wk before calving, 3 wk after calving, and every 4 wk thereafter until 15 wk after calving. Of the 26 cows, 13 cows had no or low lesion scores up to 15 wk and 13 cows had at least 1 new severe lesion or sole ulcer diagnosed between 7 and 15 wk after calving. Behavior (dry matter intake, feeding time and rate, number and size of meals, standing time, number and duration of standing bouts, location of standing, and displacements at the feed bunk) was recorded from 2 wk before calving to 3 wk after calving. Behavior during the 2 wk before calving, first 24h after calving, 1 wk after calving, and 2 to 3 wk after calving was compared between cows with and without lesions in mid lactation. Multivariate regression was used to determine the predictive value of each behavior and combination of behaviors on lesion diagnosis. Cows diagnosed with lesions in mid lactation spent more time standing than cows without lesions during the 2 wk before (832+/-29 vs. 711+/-29 min/d) and 24 h after (935+/-46 vs. 693+/-46 min/d) calving. These differences were driven by an increase in the time spent perching with front feet in the stall (241+/-22 vs. 147+/-22 min/d at 2 wk before calving) and an increase in standing bout duration (101+/-10 vs. 56+/-10 min/bout at 24 h after calving). Compared with cows without lesions, cows with lesions consumed feed at a faster rate (86+/-3 vs. 77+/-3 g/min) during the 2 wk before calving and consumed more feed (17.9+/-0.9 vs. 12.3+/-0.9 kg/d) during the 24 h after calving. The number of displacements at the feeder was not different between groups. These results indicate that a combination of feeding and standing behavior during the transition can serve as early indicators of claw horn lesions in mid lactation
Growth, biomass partitioning, and water-use efficiency of a leguminous shrub (Bauhinia faberi var. microphylla) in response to various water availabilities
No full textResponses of the endemic leguminous shrub Bauhinia faberi var. microphylla, to various soil water supply regimes were studied in order to assess water stress tolerance of seedlings. Two-month-old seedlings were grown under water supply regimes of 100, 80, 60, 40, and 20% water field capacity (FC), respectively, in a temperature and light-controlled greenhouse. Plant height and leaf number were measured monthly over a 4-month period, while water use (WU), water-use efficiency (WUE), leaf relative water content (RWC), biomass production and its partitioning were recorded at the end of the experiment. Seedlings exhibited the greatest biomass production, height, basal diameter, branch number, leaf number, and leaf area when soil content was at 100% FC, and slightly declined at 80% FC. These parameters declined significantly under 60% FC water supply, and severely reduced under 40 and 20% FC. RWC, WU and WUE decreased, while the ratio of root mass to stem mass (R:S) increased in response to decreasing water supply. Water stress caused leaf shedding, but not plant death. The results demonstrated that B. faberi var. microphylla seedlings could tolerate drought by reducing branching and leaf area while maintaining a high R:S ratio. However, low dry mass and WUE at 40 and 20% FC suggested that the seedlings did not produce significant biomass under prolonged severe water deficit. Therefore, before introducing B. faberi var. microphylla in vegetation restoration efforts, water supply above 40% FC is recommended for seedlings to maintain growth
On co-authorship for author disambiguation
No full textAuthor name disambiguation deals with clustering the same-name authors into different individuals. To attack the problem, many studies have employed a variety of disambiguation features such as coauthors, titles of papers/publications, topics of articles, emails/affiliations, etc. Among these, co-authorship is the most easily accessible and influential, since inter-person acquaintances represented by co-authorship could discriminate the identities of authors more clearly than other features. This study attempts to explore the net effects of co-authorship on author clustering in bibliographic data. First, to handle the shortage of explicit coauthors listed in known citations, a web-assisted technique of acquiring implicit coauthors of the target author to be disambiguated is proposed. Then, a coauthor disambiguation hypothesis that the identity of an author can be determined by his/her coauthors is examined and confirmed through a variety of author disambiguation experiments. (C) 2008 Elsevier Ltd. All rights reserved.X1174sciescopu
Health and growth of veal calves provided a fatty acid supplement and a dry teat
No full textVeal calves are at a high risk of disease early in life, which can lead to poor growth. Research is needed to determine interventions that can reduce disease and promote the growth of veal calves. The aim of this study was to determine the effects of fatty acid supplementation and the provision of a dry teat on the incidence of bovine respiratory disease (BRD), navel inflammation, and diarrhea, as well as calf growth. Upon arrival to a commercial veal facility (d 0), 240 Holstein bull calves from 2 cohorts were randomly assigned to 4 treatments using a 2 × 2 factorial arrangement (n = 60/treatment): (1) milk replacer (MR) without fatty acid supplementation and without access to a dry teat (control), (2) MR with fatty acid supplementation (NeoTec5g, Provimi, Brookville, OH) and without access to a dry teat (FAS), (3) MR without fatty acid supplementation and with access to a dry teat (TT), or (4) MR with fatty acid supplementation and with access to a dry teat (FAS+TT). Calves were housed in individual pens from 0 to 9 wk and then paired by treatment at wk 9. Milk replacer was fed twice daily using a step-up program. Fatty acid supplement was added to milk replacer at a feeding rate of 0.5 g/kg of body weight per head per day for the FAS and FAS+TT groups. Health exams were conducted twice weekly for 6 wk to diagnose BRD, navel inflammation, and diarrhea. Body weight, body condition score (BCS), and structural measurements were recorded at wk 0, 5, and 10. Average daily gain (ADG) was calculated for wk 1 to 5, wk 5 to 10, and wk 1 to 10. Health data were analyzed using logistic regression and are reported as relative risk. Body weight, BCS, and structural measurements were analyzed using repeated-measures ANOVA, and ADG was analyzed using a generalized linear model. There was no effect of FAS, TT, or their interaction on body weight or BCS. There was no effect of FAS on ADG wk 1 to 5, wk 5 to 10, or wk 1 to 10. There was a tendency for TT to decrease ADG from wk 1 to 5 but not from wk 5 to 10 or wk 1 to 10. There was a tendency for the interaction of FAS and TT to decrease ADG for wk 1 to 5 but not for wk 5 to 10 and wk 1 to 10. There was no effect of FAS, TT, or their interaction on the risk of BRD, diarrhea, or navel inflammation. We saw no effect of our interventions on calf health or growth. More research is needed to determine whether other factors, such as failure of passive transfer, poor ventilation, barren housing, and low milk allowance in the first few weeks after arrival, may have affected the efficacy of our interventions
Effects of supplemental vitamins E and C on the immune responses of calves
No full textTwo experiments were conducted to evaluate the effects of oral supplementation of vitamin C and vitamin E (alpha-tocopherol), alone and in combination, on immune responses of calves. In Experiment 1, 18 Holstein newborn female calves were supplemented with 0, 1, and 2 g/d of vitamin C from birth to 6 wk of age. Concentrations of ascorbic acid in blood plasma were significantly higher for supplemented calves than for control calves. No significant differences among treatments occurred in the concentrations of IgG1, IgG2, and titer to keyhole limpet hemocyanin. In Experiment 2, effects of oral supplementation of vitamins E and C on immune responses were studied using 18 Holstein female calves. Concentrations of alpha-tocopherol in blood plasma were significantly higher for supplemented than for control calves. The concentrations increased from birth to wk 1, and then very little change occurred from wk 1 to 6. Differences among treatments in the concentrations of IgG1, IgG2, IgM, and titer to keyhole limpet hemocyanin were not significant; however, concentrations of IgM in calves supplemented with vitamins E and C generally tended to be higher than those of control calves. Antibodies to keyhole limpet hemocyanin were higher at 6 wk than at 4 wk of age.LR: 20031114; PUBM: Print; JID: 2985126R; 0 (Antibodies); 0 (Antigens); 0 (Immunoglobulin G); 0 (Immunoglobulin M); 0 (keyhole-limpet hemocyanin); 1406-18-4 (Vitamin E); 50-81-7 (Ascorbic Acid); 9013-72-3 (Hemocyanin); ppublishSource type: Electronic(1
Randomized clinical trial to investigate the effectiveness of teflubenzuron for treating sea lice on Atlantic salmon
No full textA double-blind, randomized control clinical trial was performed to investigate the effectiveness of teflubenzuron in controlling sea lice Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar. A total of 40 sea cages from 3 commercial cage sites in Atlantic Canada were used in this Good Clinical Practice (GCP) trial. The teflubenzuron was administered in the feed at a dosage of 10 mg kg(-1) biomass d(-1) for 7 d. Medicated and control cages were matched by site, cage size, and pre-treatment mean lice counts using cages as the unit of concern. Post-treatment lice counts and staging of developmental stages were performed at 1 and 2 wk after the end of treatment. Chalimus stages in medicated cages were significantly lower than in control cages at 1 wk (79% reduction in mean lice counts, p < 0.001), and at 2 wk (53% reduction, p < 0.001). Mobile (pre-adult and adult) stages were also significantly reduced in medicated cages at 1 wk (69% reduction, p < 0.01), and at 2 wk (40% reduction, p < 0.01) post-treatment, respectively. Teflubenzuron was proven effective for reducing lice burdens on salmon despite the low parasite levels experienced during the trial and the recruitment of lice from the untreated cages. The use of cage as the unit of concern was an important design component of this trial.LR: 20061115; PUBM: Print; JID: 8807037; 0 (Benzamides); 70288-86-7 (Ivermectin); 83121-18-0 (teflubenzuron); ppublishSource type: Electronic(1
Discrete physiological effects of beetroot juice and potassium nitrate supplementation following 4-wk sprint interval training
No full textThis is the author accepted manuscript. The final version is available from the American Physiological Society via the DOI in this record.The physiological and exercise performance adaptations to sprint interval training (SIT) may be modified by dietary nitrate (NO3) supplementation. However, it is possible that different types of NO3 supplementation evoke divergent physiological and performance adaptations to SIT. The purpose of this study was to compare the effects of 4-wk SIT with and without concurrent dietary NO3 supplementation administered as either NO3-rich beetroot juice (BR) or potassium NO3 (KNO3). Thirty recreationally active subjects completed a battery of exercise tests before and after a 4-wk intervention in which they were allocated to one of three groups: 1) SIT undertaken without dietary NO3 supplementation (SIT); 2) SIT accompanied by concurrent BR supplementation (SIT BR); or 3) SIT accompanied by concurrent KNO3 supplementation (SIT KNO3). During severe-intensity exercise, V O2peak and time to task failure were improved to a greater extent with SIT +BR than SIT and SIT KNO3 (P 0.05). There was also a greater reduction in the accumulation of muscle lactate at 3 min of severe-intensity exercise in SIT BR compared with SIT KNO3 (P <0.05). Plasma NO2 concentration fell to a greater extent during severe-intensity exercise in SIT BR compared with SIT and SIT KNO3 (P <0.05). There were no differences between groups in the reduction in the muscle phosphocreatine recovery time constant from pre- to postintervention (P <0.05). These findings indicate that 4-wk SIT with concurrent BR supplementation results in greater exercise capacity adaptations compared with SIT alone and SIT with concurrent KNO3 supplementation. This may be the result of greater NO-mediated signaling in SIT +BR compared with SIT+ KNO3. NEW & NOTEWORTHY We compared the influence of different forms of dietary nitrate supplementation on the physiological and performance adaptations to sprint interval training (SIT). Compared with SIT alone, supplementation with nitrate-rich beetroot juice, but not potassium NO3, enhanced some physiological adaptations to training
Blueberry diets delay the onset of hypertension and reduce insulin resistance in spontaneously hypertensive stroke prone rats
No full textHypertension is a major risk factor for cardiovascular disease, the number one cause of disability and death in North America. Thus, strategies (e.g. diet modification, drugs) to manage hypertension are essential. Lowbush blueberries (Vaccinium angustifolium) are rich in polyphenolic antioxidants which are beneficial to stroke, and may have vasorelaxation effects. We fed spontaneously hypertensive stroke-prone rats (SHrSP) and control rats (CON) either control diet or a diet containing 3% freeze-dried blueberry extract for 8 wks, to determine effects of blueberry diets on systolic blood pressure (BP). BP increased in both SHrSP groups over 8 wks. However BP in SHrSP on control diets was significantly higher than in CON by wk 4 (p=0.016), while BP in SHrSP consuming blueberries was not significantly elevated relative to CON until wk 7 (p=0.001). Maximum BP was 216 ± 11 mmHg (wk 7), and 178 ± 15 mmHg (wk 8) in SHrSP consuming control and blueberry diets respectively. At wk 6, BP of SHrSP on blueberry diet was 30% lower (p=0.002) than in SHrSP on control diet. In a separate group of SHrSP fed blueberries for 6 wks, a 48% lower glucose/insulin ratio was seen compared to rats on control diet (P=0.08, n=3). These results indicate that a 3% blueberry diet is capable of delaying the onset and reducing the magnitude of hypertension, and may reduce insulin resistance in SHrSP
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