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PubMed2006

Exposure to long-day photoperiod prepubertally may increase milk yield in first-lactation cows.

Exposure to a long-day photoperiod (LDPP) increases mammary and lean growth in heifers relative to a short day (SDPP). Whether these effects influence milk yield, however, is unknown. To test the hypothesis that pre-pubertal long-day exposure would increase milk production, we assigned prepubertal heifers to LDPP (16 h of light:8 h of dark; n = 16) or SDPP (8 h of light:16 h of dark; n = 16) until the onset of puberty. At puberty, heifers were commingled and housed under natural photoperiodic conditions and standard nutritional management for dairy heifers. Heifers were bred according to body weight (BW = 385 kg) and withers height (WH = 132 cm). At parturition, BW, WH, and hip height were evaluated. Analysis of Dairy Herd Improvement Association records was used to evaluate milk yield, milk components, and somatic cell scores. Relative to SDPP (n = 12), heifers on LDPP (n = 10) had greater WH (by 2.4 cm) and BW at calving (by 55 kg). Compared with heifers housed under SDPP, LDPP heifers tended to produce more milk (750 kg of 305-d projected fat-corrected milk) during the first lactation. Relative to SDPP, prepubertal heifers exposed to LDPP during the prepubertal growth phase were taller and heavier at parturition, and tended to produce more milk during their first lactation.

Animal Nutritional Physiological Phenomena↗

PubMed2005

Assessing the appropriateness and increasing the yield of renal angiography in patients undergoing coronary angiography: a scoring system.

The real appropriateness and yield of a coincident renal angiography in patients undergoing coronary angiography is still a matter of debate. We have attempted to defined a scoring system to assess the need for renal angiography in patients undergoing diagnostic coronary angiography. We retrospectively reviewed our invasive cardiology database searching for patients underwent coincident screening abdominal aorta angiography to detect occult renal artery stenosis were analyzed and entry in a development set. Univariate and multivariate logistic regression analyses were employed to determine independent predictors of extra-cardiac atherosclerotic involvement. Based on the odds ratio, identified variables were assigned to a weighted integer; the sum of integers was a total score. Thus, the scoring model was tested on a validation set based on a prospective series of consecutive patients enrolled on the basis of an identified cut-off score. In the development set (635 patients, mean age 68+/-11.2 years) an angiographically significant RAS was observed in 20% of cases (128 patients). The rate of significant angiographic findings increased proportionally with increasing risk score (Pearson coefficient 0.98). A score of >or=5 was identified to be the cut-off beyond which renal angiography seems to have a sufficiently good efficacy in detecting clinically significant renal artery diseases (>30% of patients). In the validation set the patients were enrolled on the basis of the identified cut-off score (317 patients, mean age 69+/-14.1 years): angiographic occult RAS was diagnosed in 156/317 (49.2%) patients of the validation set versus 128/635 (20%) patients of the development set, p<0.01. This scoring system, once applied in standard medium-high volume cath labs, may be effective in increasing the yield of renal artery angiography in patients undergoing coronary angiography.

Aged↗

PubMed1998

Adaptation to high CO2 concentration in an optimal environment: radiation capture, canopy quantum yield and carbon use efficiency.

The effect of elevated [CO2] on wheat (Triticum aestivum L. Veery 10) productivity was examined by analysing radiation capture, canopy quantum yield, canopy carbon use efficiency, harvest index and daily C gain. Canopies were grown at either 330 or 1200 micromoles mol-1 [CO2] in controlled environments, where root and shoot C fluxes were monitored continuously from emergence to harvest. A rapidly circulating hydroponic solution supplied nutrients, water and root zone oxygen. At harvest, dry mass predicted from gas exchange data was 102.8 +/- 4.7% of the observed dry mass in six trials. Neither radiation capture efficiency nor carbon use efficiency were affected by elevated [CO2], but yield increased by 13% due to a sustained increase in canopy quantum yield. CO2 enrichment increased root mass, tiller number and seed mass. Harvest index and chlorophyll concentration were unchanged, but CO2 enrichment increased average life cycle net photosynthesis (13%, P < 0.05) and root respiration (24%, P < 0.05). These data indicate that plant communities adapt to CO2 enrichment through changes in C allocation. Elevated [CO2] increases sink strength in optimal environments, resulting in sustained increases in photosynthetic capacity, canopy quantum yield and daily C gain throughout the life cycle.

Adaptation, Physiological↗

PubMed1983

Caffeine-mediated release of alpha-radiation-induced G2 arrest increases the yield of chromosome aberrations.

Severe and partly irreversible G2 arrest caused by americium-241 alpha-particles in Chinese hamster V79 cells acted as a competing process to the yield of detectable aberrant mitoses at metaphase. With increasing dose of alpha-radiation an increasing fraction of cells was irreversibly arrested in G2 with the consequence of interphase death before the first post-irradiation mitosis. This irreversible G2 arrest (demonstrated by flow cytofluorometry and mitotic indices) could be overcome by adding caffeine 8 hours after irradiation, the time point of maximum G2 arrest (80-90 per cent of all cells). Within 3.5 hours the number of aberrant mitoses increased by this treatment from 54 to 96 per cent and from 65 to 99.9 per cent for doses of 1.75 and 4.38 Gy of alpha-particles, respectively. The aberration frequency per mitotic cell, scored as chromatid and isochromatid breaks, rings, interchanges and dicentrics increased by a factor of about 3 after releasing G2 arrested cells. The frequency distribution of aberrations per cell revealed that, after 4.38 Gy, 58 per cent of the formerly G2-arrested cells had more than five aberrations per cell compared to only 8 per cent without the interaction of caffeine.

Alpha Particles↗

PubMedDate not supplied

[New ways to increasing the yield of laccase from Panus tigrinus fungi].

We optimized the conditions for production of laccase by lignolytic fungi Panus tigrinus 8/18. 2,4-Dimethylphenol was used as an aromatic inductor. The addition of 2,4-dimethylphenol and 2 mM CuSO4 to a rich medium was followed by a tenfold increase in the yield of this enzyme. Additional treatment of the medium with perftoran (oxygen-carrying agent) and immobilization of the fungus on polycaproamide fibers increased significantly laccase activity in the medium. The conditions for cultivation of P. tigrinus fungi were optimized. It allowed us to increase laccase activity in the medium by 25 times (compared to activity of the enzyme obtained with previously described methods).

Basidiomycota↗

PubMed2004

Glucose metabolism in lactating cows in response to isoenergetic infusions of propionic acid or duodenal glucose.

A bibliographical study showed that increasing supplies of glucogenic nutrients lead to a curvilinear increase in milk and protein yield. Increased post-hepatic glucose availability may be involved in the increase in milk yield. In the present experiment, 5 dairy cows were arranged in a 5 x 5 Latin square design to compare the respective effects of 2 amounts of either duodenal glucose or ruminal propionic acid (C3) on glucose metabolism. Treatment consisted of a grass silage-based diet supplemented with glucogenic nutrients infused into the rumen as a mixture of volatile fatty acids (control) or C3 (6.5 and 13 mol/d) or as glucose (3.4 and 6.9 mol/d) infused into the duodenum. Treatments were isoenergetic and isonitrogenous and contained 100 and 115% of energy and protein requirements, respectively, according to the Institut National de la Recherche Agronomique. Glucose appearance rate (Ra) tended to increase with the level of infusions of both glucogenic materials and with the high dose of duodenal glucose. Plasma insulin-like growth factor-I (IGF-I) concentration increased with the infusion of glucogenic materials compared with the control and was significantly higher with glucose than with C3 treatments. This experiment did not indicate whether the increased Ra was the key mechanism to increased milk yield because milk yield only tended to increase and the standard error for Ra was high. With the high dose of glucose infused into the duodenum, the Ra increase was greater than the increased lactose production in milk. Because of that connection, IGF-I may also be involved by favoring the glucose utilization by the mammary gland.

Animal Feed↗

PubMed1992

Evaluation of osmium(II)-nitrosyl complexes as a method to increase the yield of the 191Os-191mIr generator.

The nitrosyl complexes pentachloronitrosylosmate(II), [OsCl5(NO)]2-, and hydroxytetranitronitrosylosmate(II), [Os(OH)(NO2)4(NO)]2-, were evaluated as parent species for use on the 191Os-191mIr generator in an attempt to increase the 191mIr yield of the generator by providing a direct route to a chemically stable 191mIr daughter. The uptake of the 191Os-labeled complexes by the inorganic ion-exchangers ZrO2, SnO2, PbS, MnO2 and Al2O3 and the organic resin AG MP-1 was measured and prototype generators were prepared using those exchangers that demonstrated greater than 90% uptake of the 191Os-labeled complexes. The 191mIr(III)-nitrosyl complexes produced subsequent to beta- decay of the 191Os-nitrosyl parent complexes were found to undergo secondary chemical reactions to form nitro (NO2-) complexes that were tightly retained on the ion exchanger limiting 191mIr yield to less than 5%.

Iridium Radioisotopes↗

PubMed2006

MRT letter: high speed scanning has the potential to increase fluorescence yield and to reduce photobleaching.

True confocal microscopy requires point-shaped illumination and detection. To generate an image, a diffraction limited spot is moved over the sample. Single spot scanning has suffered in the past from low image rates; a solution is the employment of very fast scanning devices (resonant scanners) for x-movement. In the process of introducing resonant scanning devices, it was found that both signal yield is improved and bleaching is decreased-in contrary to the assumed performance. This article will show by a simple and well understood model a straightforward explanation for the potential increase of signal yield and decrease in photobleaching. The time that is ruling the dose-rate effects is the effective time; a fluorochrome is illuminated. This time depends on the diameter of the spot that is moved over the sample and the speed at which the spot moves. In essence, the scan process causes a pulsed illumination of the fluorochromes. Various schemes of pulsed illumination are simulated with a fluorescence model. The model includes a dark state, where fluorochromes will exit the fluorescence process and slowly decay back into the ground state. Upon splitting a single dose into two pulses separated by a dark time-reflecting an increased scan speed-the amount of fluorescence emission is increased and bleaching is reduced. These results show a potential increase of fluorescence and a lower photobleaching upon higher scan speed. As illumination during the bleach-phase in a FRAP-experiment is similar to a light pulse, the findings also suggest to critically consider the very beginning of fluorescence recovery in terms of triplet relaxation process that potentially could falsify the measurements.

Fluorescence↗

PubMed1996

Method for increasing the yield of properly folded recombinant human gamma interferon from inclusion bodies.

A strategy is described for improved refolding and purification of recombinant human gamma interferon (rh-IFN gamma), which could warrant a higher yield and specific activity than reported previously. The optimal conditions of refolding are obtained by addition of a labilizing agent, L-arginine, in the refolding buffer. A 10-fold increase in the yield was observed with 0.5 M L-arginine, compared with renaturation in its absence. By varying renaturation parameters, the conditions that allow functional refolding of approximately 25-30% of the recombinant protein have been standardized. A simple process is also described for the purification of rh-IFN gamma. The purification involves a single-column chromatography on S-Sepharose, after refolding of rh-IFN gamma in arginine containing buffer. This procedure has consistently produced rh-IFN gamma having a purity of at least 97%, the rest being the aggregated form of gamma interferon. The purified protein is a dimer under non-denaturing conditions and has a specific activity of 2 x 10(8) IU mg-1 protein, as measured by viral cytopathic assay.

Arginine↗

PubMedDate not supplied

Protection from cell death in cultured human fetal pancreatic cells.

Endocrine cells from the human fetal pancreas will proliferate in vitro on extracellular matrix but lose hormone expression, and redifferentiation requires removal of the expanded cells from the matrix and reaggregation into cell aggregates. However, extensive cell death occurs during manipulation and culture. The mechanism of cell death was examined at each stage throughout the process under different experimental conditions to determine optimal protocols to increase cell viability. During shipment, the addition of trehalose to the media to prevent necrosis increased yield 17-fold, while during culture as islet-like cell clusters the apoptosis inhibitor Z-VAD increased yield 1.8-fold. Following disruption of cell matrix interactions and reaggregation, there was marked evidence of apoptotic bodies by the TUNEL assay. Addition of nicotinamide or Z-VAD, or removal of arginine from the media during reaggregation, reduced the number of apoptotic bodies and the effect was additive. However, a combination of treatments was necessary to significantly increase the yield of viable cells. We conclude that cell death of human fetal pancreatic tissue in culture results from both necrosis and apoptosis and that understanding the mechanisms at the cellular level will lead to protocols that will improve cell viability and promote beta-cell growth.

Amino Acid Chloromethyl Ketones↗

PubMed1991

Amniocentesis with increased cell yield, obtained by filtration and reinjection of the amniotic fluid.

In order to increase the cell numbers obtained by amniocentesis, a new amniocentesis technique has been developed and we report preliminary results. The amniotic fluid is aspirated in the usual manner and reinjected immediately into the amniotic cavity after passage through a filter which retains the cells from the fluid. By this procedure, the cells from a relatively large volume of amniotic fluid are concentrated on the filter while only a small volume of amniotic fluid is finally removed. The method has been tested on 30 pregnant women referred for prenatal diagnosis. The mean culture time was 8.3 days and no immediate side-effects were observed.

Journal Article↗

PubMed1993

Fed-batch culture of insect cells: a method to increase the yield of recombinant human nerve growth factor (rhNGF) in the baculovirus expression system.

A fed-batch method was developed which increased the density of insect cells (Spodoptera frugiperda, Sf-9 cells) in suspension culture and the feeding of nutrients improved the yield of a recombinant protein produced by a baculovirus expression system. Analysis of spent medium samples indicated that depletions of glucose and glutamine correlated with the retardation of cell growth. Feeding of a mixture of nutrients consisting of glucose, glutamine, yeastolate and lipids solution restored the growth rate. In fed-batch culture, cell density was increased from 3 x 10(6) cells per ml to 1.2 x 10(7) cells per ml and the increased cell density enhanced the yield of the desired recombinant product, in this case, human nerve growth factor (rhNGF). The optimal conditions for the production of rhNGF were also defined by selecting the appropriate viral multiplicity of infection (MOI). At a cell density of 5 x 10(6) ml-1, a MOI of 0.05 (plaque forming units per cell) gave the highest yield of rhNGF in culture fluid 3 d post-infection. The yield of rhNGF was 20 mg l-1. The fed-batch method was scaled up to 12 l stirred bioreactor.

Animals↗

PubMed1995

Effect of substituting steam-flaked sorghum for concentrate on lactation and digestion in dairy cows.

Thirty-five lactating cows (110 DIM), allotted to five dietary treatments for 70 d, were fed 0, 15, 30, or 45% of dietary DM as steam-flaked sorghum grain (360 g/L) in place of equal amounts of a mixture (DM basis) of 40% steam-rolled corn, 13% rolled barley, 20% wheat mill run, and 27% ground beet pulp in four diets. Thinly flaked sorghum grain (283 g/L) was also fed at 15% of dietary DM. The DMI tended to increase as flaked sorghum increased. Yields of milk and milk protein and percentages of milk protein and SNF increased linearly as sorghum increased. Milk yield of cows fed 15% of DM as the thinly flaked sorghum was higher than for cows fed the 360 g/L flake at 15% and similar to that of cows fed the 360 g/L flake at 30 or 45%. Feed efficiencies and changes in BW and body condition score were unaffected by treatment. As steam-flaked sorghum increased, digestibilities of DM, OM, ADF, NDF, and CP tended to decrease, except for the thinly flaked sorghum fed at 15% of DM. Apparent starch digestibility in the total tract was unaltered by diet. The 30 to 45% of DM fed as steam-flaked sorghum grain (360 g/L) increased yields of milk and milk protein, and thinly flaked sorghum (283 g/L) fed at 15% of DM increased milk yields over that of the control diet or that with the 360 g/L flake at 15% of DM.

Animal Feed↗

PubMed2004

Increased milk yield in transgenic mice expressing insulin-like growth factor 1.

Insulin-like growth factor 1 (IGF-1) mediates many of the actions of growth hormone. Overexpression of IGF-1 was reported to have endocrine and paracrine/autocrine effects on somatic growth in transgenic mice. To study the paracrine/autocrine effects of IGF-1 in mammary gland, transgenic mice were produced by pronuclear microinjection of a construct containing a bovine alpha-lactalbumin (alpha-LA) promoter linked to an ovine IGF-1 cNDA. This alpha-LA promoter has previously been shown to direct expression of a human factor VIII gene specifically to the mammary gland of transgenic mice. Three transgenic mouse lines were established as a result of microinjection of 398 embryos. Transgene expression was found in mammary gland at day 1 of lactation from these three lines. Progeny test were carried out by mating two transgenic males/one transgenic female to two nontransgenic females/one nontransgenic male. Mice from one line (line 1225) were all nonexpressors and the other (line 1372) failed to produce offspring. Milk yield was analyzed in the line 1137 that produced 10 mice, of which three were transgenic females and three nontransgenic females. All of the three transgenic females showed integration of the transgene and expressed transgene IGF-1 mRNA in the mammary gland. Milk yields from days 5, 10, and 15 of lactation were significant greater in transgenic expressors than in their nontransgenic littermates. Specifically, there is 17.9% increase in total milk yield from these three days for transgenics compared with nontransgenics. These results demonstrate that local overexpression of IGF-1 in transgenic mice is capable to stimulating milk yield during the first lactation.

Animals↗

PubMed1995

Plasma cryoprecipitation studies: major increase in fibrinogen yield by albumin enrichment of plasma.

The present studies compared fibrinogen yields of cryoprecipitate (Cr) obtained under differing conditions, and focused on yields from albumin enriched plasma. Addition of human albumin to fresh plasma collected into CPDA-1, citrate, or heparin (4 U/ml) resulted in an average of 2.8 fold (+/- 0.34 SD, n = 17) increase in yields of Cr fibrinogen. This albumin effect was shown with undefatted and defatted albumin, fibrinogen yields increasing in the range of 2-6 g of albumin added/dl of plasma and plateauing thereafter. Similarly increased were yields of fibronectin, plasminogen and factor XIII, but not of factor VIII or of von Willebrand factor. By electrophoretic analyses, Cr fibrinogen from albumin enriched and that from untreated plasma did not differ. Fibrin related measurements disclosed that the albumin enhancement of fibrinogen yield did not result form increased fibrin formation in Cr. This enhancement was shown in plasma that had been enriched with soluble fibrin to increase its yield and in that which had been subjected to hirudin, to high ionic strength, or to dilution to decrease its Cr fibrinogen yield. The results suggest a water exclusion effect, inducing cryoprecipitation of otherwise soluble fibrin/fibrinogen complexes.

Albumins↗

PubMed2000

[CT- and ultrasound-guided biopsies: prospective comparison of fine-needle aspiration with true-cut biopsy in 103 patients].

PURPOSE: A prospective comparison of FNAB and TCB was performed in an identical set of patients and lesions. METHODS: In 103 patients focal lesions were biopsied by US- or CT-guidance with at least one FNAB and TCB each. Complications were registered and documented. Cytological and histological specimens were evaluated independently. A final diagnosis was then attempted by consensus. RESULTS: A total of 253 punctures was performed with sufficient tissue in 72.8% (FNAB) and 85.4% (TCB) of the cases. Diagnosis was possible in 68% (FNAB) and 80.6% (TCB). After combined evaluation of both specimens the diagnostic yield increased to 91.3%. Minor complications without clinical sequelae were observed in 21 patients. CONCLUSION: A diagnostic strategy with the combined use of FNAB and TCB increases the diagnostic yield in image-guided punctures. Even though this approach needs at least two separate punctures, the complication rate does not increase.

Biopsy↗

PubMed1996

Percutaneous biopsy in diffuse liver disease: increasing diagnostic yield and decreasing complication rate by routine ultrasound assessment of puncture site.

OBJECTIVE: To evaluate the usefulness of routine ultrasound assessment of puncture site before performing percutaneous biopsy in diffuse liver disease. Seven hundred fifty-three consecutive patients were studied retrospectively. METHODS: Serial scanning of the last intercostal spaces allowed us to establish the most suitable access to the thicker liver parenchyma (assessing the most favorable angulation of the needle too), avoiding the puncture of adjacent organs; no more than 1 min was necessary for such a determination. RESULTS: In 99.4% of patients, a definitive or indicative pathological diagnosis of chronic liver disease was obtained. Only one hemorrhagic complication (0.13%) occurred, requiring no surgical treatment or blood transfusion. Three cases of vasovagal reaction occurred (0.40%): two of these recovered spontaneously, while the other one needed i.v. administration of atropine. Mortality was 0 in our series. CONCLUSIONS: Routine ultrasound of the puncture site is a quick method of assessment, allowing one to increase the diagnostic yield of percutaneous liver biopsy and to maintain low complication rates for such a procedure.

Biopsy, Needle↗

PubMed1990

Chlorophyll a fluorescence measurements of isolated spinach thylakoids obtained by using single-laser-based flow cytometry.

Flow cytometry data of spinach thylakoid membrane preparations indicate the presence of a homogeneous thylakoid population. Fluorescence data from a flow cytometer and comparison with data from two other fluorometers show that chlorophyll a fluorescence detected with a flow cytometer has the character of maximum fluorescence (Fmax), not of the constant component (Fo). This conclusion is important since Fo measures fluorescence that is affected mostly by changes in excitation energy transfer and Fmax-Fo (the variable fluorescence) by changes in photochemistry. This was demonstrated by: 1) The light intensity as well as diffusion rate dependence of the quenching effect of various quinones (p-benzoquinone, phenyl-benzoquinone, and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, DBMIB) on fluorescence yield; quenching for the same concentration of these quinones was lower at the higher than at the lower light intensities. 2) Temperature dependence of the fluorescence yield; increasing the temperature from 20 to 70 degrees C did not show an increase in fluorescence yield using a flow cytometer in contrast to measurements with weak excitation light, but similar to those obtained for Fmax. 3) Addition of an inhibitor diuron up to 100 microM did not change the fluorescence intensity. A comparison of quenching of fluorescence by various quinones obtained by flow cytometry with those by other fluorometers suggests that the high intensity used in the cytometry produces unique results: the rate of reduction of quinones in much larger than the rate of equilibration with the bulk quinones.

Chlorophyll↗