SEARCH · PubMed Health

Results for “yield increase”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed1998

Noncytopathogenic bovine viral diarrhea virus (BVDV) reduces cleavage but increases blastocyst yield of in vitro produced embryos.

The growing application of in vitro embryo production systems that utilize slaughterhouse tissues of animals of unknown health status conveys the risk of disease transmission. One pathogen of concern in this regard is bovine viral diarrhea virus (BVDV), and the objective of this study was to investigate the effect of BVDV on in vitro embryonic development. A bovine in vitro embryo production system was experimentally infected with BVDV at 2 stages: prior to in vitro maturation by incubating cumulus-oocyte complexes (COC) with virus (strain Pe515; titer 10(6.2) tissue culture infective dose (TCID)50/mL) or vehicle for 2 h, and then during in vitro culture by the use of BVDV infected granulosa cells. Exposure to BVDV throughout in vitro production reduced cleavage rates (P = 0.01) but increased (P = 0.05) the number of embryos that reached the 8-cell stage when expressed as a percentage of cleaved oocytes. Blastocyst yield was increased by the presence of virus when expressed as a proportion of oocytes (P = 0.0034) or of those cleaved (P < 0.0001). The percentage of total blastocyst yield on Days 7, 8 and 9 for the control and virus treatments was 20, 51, 29 and 29, 41, and 29%, respectively, indicating that the rate of blastocyst development was nonsignificantly faster in the virus-treated group (P = 0.06). These results indicate that the presence of non-cytopathogenic BVDV in an in vitro production system may reduce cleavage rates but allow those cleaved to develop to blastocysts at a higher rate.

Animals↗

PubMed2001

Low-temperature increases the yield of biologically active herring antifreeze protein in Pichia pastoris.

Antifreeze proteins and antifreeze glycoproteins are structurally diverse molecules that share a common property in binding to ice crystals and inhibiting ice crystal growth. Type II fish antifreeze protein of Atlantic herring (Clupea harengus harengus) is unique in its requirement of Ca(2+) for antifreeze activity. In this study, we utilized the secretion vector pGAPZalpha A to express recombinant herring antifreeze protein (WT) and a fusion protein with a C-terminal six-histidine tag (WT-6H) in yeast Pichia pastoris wild-type strain X-33 or protease-deficient strain SMD1168H. Both recombinant proteins were secreted into the culture medium and properly folded and functioned as the native herring antifreeze protein. Furthermore, our studies demonstrated that expression at a lower temperature increased the yield of the recombinant protein dramatically, which might be due to the enhanced protein folding pathway, as well as increased cell viability at lower temperature. These data suggested that P. pastoris is a useful system for the production of soluble and biologically active herring antifreeze protein required for structural and functional studies.

Animals↗

PubMedDate not supplied

Increased viral yield and symptom severity result from a single amino acid substitution in the turnip yellow mosaic virus movement protein.

Turnip yellow mosaic virus is a positive-strand RNA virus that produces light green or yellow-green mosaic symptoms in Chinese cabbage plants. We have characterized a strain that produces nearly uniform yellow-green chlorosis in systemically infected Chinese cabbage leaves. The increased symptom severity is due to the single nucleotide substitution U1888-->C, which results in a tyrosine to histidine substitution in the movement protein encoded by ORF-69. Coding by the overlapping ORF-206 is not affected. The mutation results in fourfold higher accumulations of viral products in systemically infected Chinese cabbage leaves but does not affect viral replication in isolated protoplasts. These results suggest that the increased viral yield and symptom severity result from improved viral spread in the host plant. These effects were specific to Chinese cabbage, since neither viral yield nor symptoms in turnips were affected by the U1888-->C mutation.

Amino Acids↗

PubMed2004

Incompatible mechanical properties in compact bone.

The covariation of a number of mechanical of properties, and some physical characteristics, of compact bones from a wide range of bones were examined. Young's modulus was well predicted by a combination of mineral content and porosity. Increasing Young's modulus was associated with: increasing stress at yield, increasing bending strength, and a somewhat higher resilience, tensile strength and fatigue strength. Contrarily, in the post-yield region a higher Young's modulus (and more clearly, a higher mineral content) was associated with: a reduced work to fracture in tension, a reduced impact strength and an increased notch sensitivity in impact. Increasing porosity is associated with deleterious effects in the pre-yield region, but has little effect in the post-yield region. Bone, like many other materials, is unable to have good qualities in both the pre- and post-yield regions. Since an increase in mineral or Young's modulus is more potent, that is deleterious, in the post-yield than it is advantageous in the pre-yield region, it is likely that mineral content will be selected to be slightly lower than would be the case if it were equally potent in both regions. As is usual in biology, different adaptive extremes are incompatible.

Animals↗

PubMedDate not supplied

Failure of postfiltration leukapheresis plasma to increase granulocyte yields.

Autologous plasma collected either during or immediately after continuous flow filtration leukapheresis (CFFL) was infused prior to subsequent donations in an attempt to induce granulocytosis and to augment granulocyte yields. Granulocytosis did not occur in the 15 to 20 minutes following plasma administration and no increase in granulocyte yields could be demonstrated. In addition, the plasma infusion did not affect the timing or magnitude of the transient granulocytopenia which characteristically occurs during CFFL. Although infusion of postfiltration leukapheresis plasma does not appear to feasible or practical means of enhancing granulocyte collection, it may still serve as a valuable tool in the study of granulocyte kinetics.

Agranulocytosis↗

PubMed1991

Increasing the yield of ventricular tachycardia induction: a prospective, randomized comparative study of the standard ventricular stimulation protocol to a short-to-long protocol and a new two-site protocol.

Programmed ventricular stimulation with a standard protocol that used up to three extrastimuli was compared prospectively with a short-to-long protocol and a two-site protocol in 77 consecutive patients undergoing electrophysiologic study in an attempt to increase the yield of ventricular tachycardia (VT) induction. The short-to-long protocol uses a train of eight stimuli at a short cycle length and up to two extrastimuli. The two-site protocol is similar to the standard protocol but delivers the last extrastimulus via a second spatially separated right ventricular catheter. Patients were divided into two groups based on indications for study: group 1 included 45 patients with syncope, nonsustained VT, or both, and group 2 included 32 patients with a history of sustained VT, sudden cardiac death, or both. The yield of VT induction with the short-to-long protocol was less than that with the standard protocol. In none of the patients in group 1 in whom the standard protocol results were negative did the short-to-long protocol produce sustained VT. Only two patients, both in group 2, had sustained arrhythmias induced by the short-to-long protocol when the standard protocol results were negative: one had sustained VT induced and one with long QT syndrome had ventricular fibrillation (VF) induced with the short-to-long protocol. However, the short-to-long protocol failed to induce sustained VT in seven patients in whom the standard protocol produced sustained VT. All seven of these patients required three extrastimuli with the standard protocol for induction of VT.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1987

Factors controlling the hormesis response in irradiated seed.

Ionizing radiation at very low doses frequently has a stimulating or hormetic effect on the growth of organisms. Irradiation of seed before planting can stimulate early plant growth, leading to advanced maturity and increased yield. The unreliability of this response has limited its application. However, the technique has been extensively studied and now is practiced on a large scale on some farms in certain countries. Our research has addressed various factors that may determine the stimulation response with the goal of developing an ability to predict the occurrence of increased economic yield. In this paper, we discuss several of these factors in light of our data and data from other field studies in Canada. A hormesis response was observed for most species studied, but varied among cultivars and among seed lots within a cultivar. Seed condition may be the underlying factor in these effects. The response was most frequently evident at very early stages of growth and was often masked in subsequent growth. This suggests that the hormesis phenomenon in seeds may be quite common and is not reliably manifest in advanced maturity or yield increases because of environmental effects. Storage time after irradiation must be minimized to gain the greatest response. There is little evidence to suggest that the photon energy or dose rate of the radiation source is an important factor.

Dose-Response Relationship, Radiation↗

PubMed1990

Treatment of dairy cows with recombinant bovine somatotropin: genetic and phenotypic aspects.

Thirty-four multiparous and primiparous Holstein cows were utilized to examine the association between the response to long-term administration of recombinant bovine somatotropin and the cow's phenotypic and genetic production potential. Cows representing a range of phenotypic and genetic production potentials were assigned to one of four treatment groups: 0, 12.5, 25.0, or 50.0 mg recombinant bovine somatotropin daily. They were injected daily for 266 d beginning on d 24 to 35 postpartum. Pretreatment milk and fat yields were used to predict daily yields over the lactation and allowed treatment groups to serve as their own controls. Actual minus predicted yield estimated the response to treatment for milk, fat, and FCM for each cow. Milk composition (fat, protein, and lactose percentage) was not significantly affected by treatment. Response in yield for milk, fat, and FCM was significant during the treatment period (266 d). Milk yield increased by 18.5, 19.9, and 21.4%; fat yield increased by 13.4, 20.3, and 18.1%; and FCM increased by 16.3%, 19.7%, and 21.1% after receipt of 12.5, 25.0 and 50.0 mg recombinant bovine somatotropin, respectively. Differences in response were not significant. The dramatic effect recombinant bovine somatotropin has on production requires that alternative approaches be adopted in the future for accurate genetic evaluation of sires and dams if somatotropin is discriminantly used in the national herd.

Analysis of Variance↗

PubMed2001

Increasing diagnostic yield in allergic fungal sinusitis.

Diagnosis of allergic fungal sinusitis (AFS) in patients who present with rhinosinusitis and polyposis is based upon certain clinical, histopathological and mycological histopathological criteria are the demonstration of fungal hyphae in allergic mucin and absence of tissue invasion in the excised polyps. Previous reports have indicated difficulty in demonstrating fungal hyphae on histological examination in up to 75 per cent of cases. Analysis of a series of 25 patients with AFS, suggested methods to ensure demonstration of fungal hyphae and thus increase diagnostic yield in cases with suspected AFS. criteria. Specific diagnostic

Coloring Agents↗

PubMed1998

Stereotactic biopsy of intracranial brain lesions. High diagnostic yield without increased complications: 65 consecutive biopsies with early postoperative CT scans.

Diagnostic yield and complication rate were analyzed for a series of 65 consecutive stereotactic biopsies of intra-axial brain lesions. The diagnostic yield was 98.5 +/- 1.5% and the complication rate was 1.5%. A median number of 14 biopsies (range 1-48) were taken per lesion. The biopsy sites followed a clockwise pattern, going from the superficial margin to the center and the deep margin of the lesion with respect to the inner table of the skull. A side window cannula biopsy needle was used. All patients underwent immediate postoperative CT scans within 4 h of biopsy to rule out intracranial complications. All patients were discharged within 24 h after biopsy, unless medical reasons unrelated to the biopsy required further hospitalization. We attribute the high diagnostic yield in our series to the high number of systematically taken biopsies per lesion. The higher number of biopsies did not lead to an increase in complications. From our experience, it appears safe to discharge patients the same day or within 24 h after a stereotactic biopsy if the postoperative CT shows no complication. Stereotactic biopsy could often safely be performed on an outpatient basis.

Adolescent↗

PubMed1991

Tuberculous pleural effusions: increased culture yield with bedside inoculation of pleural fluid and poor diagnostic value of adenosine deaminase.

A prospective study of 111 adult patients with a pleural effusion was carried out in an area with a high prevalence of tuberculosis to compare the yield of bedside with laboratory inoculation of pleural fluid, and the yield and speed of a radiometric mycobacterial culture system (BACTEC) with that of conventional culture. The use of adenosine deaminase activity in pleural fluid as a diagnostic test for tuberculosis was also evaluated. In the 62 cases of tuberculosis confirmed histologically or by culture, or both, the BACTEC system had the same culture yield as conventional mycobacterial culture (positive in 14 cases-23%), but was significantly faster (18 versus 33 days). Bedside inoculation had a culture yield significantly higher than laboratory inoculation in the 24 patients tested (11 versus four). The remaining three diagnostic categories were malignant (28), miscellaneous (10), and undiagnosed (11). Median adenosine deaminase activity was significantly higher in tuberculous effusions than in any of the other categories, but there was considerable overlap between the groups. It is concluded that the BACTEC system is significantly faster than conventional mycobacterial culture and that bedside inoculation of pleural fluid substantially increases culture yield. Adenosine deaminase does not provide as valuable a diagnostic test of pleural tuberculosis as has been suggested.

Adenosine Deaminase↗

PubMed2005

Novel pathway engineering design of the anaerobic central metabolic pathway in Escherichia coli to increase succinate yield and productivity.

A novel in vivo method of producing succinate has been developed. A genetically engineered Escherichia coli strain has been constructed to meet the NADH requirement and carbon demand to produce high quantities and yield of succinate by strategically implementing metabolic pathway alterations. Currently, the maximum theoretical succinate yield under strictly anaerobic conditions through the fermentative succinate biosynthesis pathway is limited to one mole per mole of glucose due to NADH limitation. The implemented strategic design involves the construction of a dual succinate synthesis route, which diverts required quantities of NADH through the traditional fermentative pathway and maximizes the carbon converted to succinate by balancing the carbon flux through the fermentative pathway and the glyoxylate pathway (which has less NADH requirement). The synthesis of succinate uses a combination of the two pathways to balance the NADH. Consequently, experimental results indicated that these combined pathways gave the most efficient conversion of glucose to succinate with the highest yield using only 1.25 moles of NADH per mole of succinate in contrast to the sole fermentative pathway, which uses 2 moles of NADH per mole of succinate. A recombinant E. coli strain, SBS550MG, was created by deactivating adhE, ldhA and ack-pta from the central metabolic pathway and by activating the glyoxylate pathway through the inactivation of iclR, which encodes a transcriptional repressor protein of the glyoxylate bypass. The inactivation of these genes in SBS550MG increased the succinate yield from glucose to about 1.6 mol/mol with an average anaerobic productivity rate of 10 mM/h (approximately 0.64 mM/h-OD600). This strain is capable of fermenting high concentrations of glucose in less than 24 h. Additional derepression of the glyxoylate pathway by inactivation of arcA, leading to a strain designated as SBS660MG, did not significantly increase the succinate yield and it decreased glucose consumption by 80%. It was also observed that an adhE, ldhA and ack-pta mutant designated as SBS990MG, was able to achieve a high succinate yield similar to SBS550MG when expressing a Bacillus subtilis NADH-insensitive citrate synthase from a plasmid.

Anaerobiosis↗

PubMed1986

Effect of genetic selection for milk yield and increased milking frequency on plasma growth hormone and prolactin concentration in Holstein cows.

Fifty Holstein cattle, either second to fourth generation daughters of cows randomly bred to non-commercial sires originating in the Virginia Tech dairy herd (estimated mean PDM84 = -455 kg, control animals), or daughters of cows bred to commercially available sires (mean PDM84 = +368 kg, selection animals), were randomly assigned to be milked twice or thrice daily starting at parturition. Serial blood samples were collected via jugular cannulae at 30, 90 and 200 d post-partum (DPP) during both the first and second lactations. Blood samples were collected for 3 h prior to and 4 h following thyrotropin releasing hormone (TRH) administration, and were analyzed for growth hormone (GH) and prolactin (PRL) concentrations. Dry matter intake, body weight and milk yield and fat content were used to calculate net energy balance (NEB) of animals at each DPP sampling period. Mean plasma GH concentrations were greater (P less than .01) in selection vs control animals both before and after TRH administration, and decreased (P less than .01) with advancing lactation (30 greater than 90 greater than 200 DPP). However, NEB was not influenced by genetic merit, implying that observed differences in GH concentrations were not due to that trait. Plasma PRL concentrations were not affected by genetic merit or DPP, but were greater (P less than .01) in the second vs first lactation. Neither PRL or GH concentrations were affected by frequency of milking. The results support the contention that increased plasma GH concentrations are associated with selection for increased milk yield.

Animals↗

PubMed1984

Effect of varying protein and energy densities in complete rations fed to cows in first lactation.

Sixty-three Holstein cows in first lactation were allotted randomly at 28 days postpartum to receive one of nine rations in a 3 X 3 factorial design. Rations had crude protein 12, 15, or 18% in each of three energy densities from ratios of forage:concentrate of 75:25, 55:45, and 35:65. Corn silage and hay crop silage were combined in a ratio of 2:1 (dry basis) in each case, and diets were offered for ad libitum intake as complete feeds for an 11-wk experimental period plus 2 wk for a digestion trial. In regression analysis as energy density increased, feed intake, milk yield, milk protein, and lactose yields increased linearly, urea nitrogen in blood plasma decreased linearly, and milk fat percent and yield decreased curvilinearly. As dietary protein increased, feed intake, fat-corrected milk, milk fat yield, and plasma urea nitrogen increased linearly, and yields of milk, solids-corrected milk, milk protein, and lactose increased curvilinearly. Actual milk yield adjusted for dry matter intake increased with greater energy density but not with higher protein concentration. Increases of energy and protein each resulted in linear increases of digestibility of dry matter, crude protein, and energy of diets. There were no interactions of energy X protein for these measurements. Cows in first lactation will increase milk production in response to increasing protein over a range of energy densities when feed intake is increased.

Animals↗

PubMed1987

Higher yields and increased purity of in vitro grown Toxoplasma gondii.

An improved method for in vitro cultivation of Toxoplasma gondii is described. Commonly, confluent cell monolayers are infected with Toxoplasma; higher yields and an increased purity could be obtained instead when host cells were immediately infected after subculture: Depending on the initial parasite inoculum 2-3 fold increased multiplication rates were achieved and simultaneously the amount of host cell debris was reduced to 10-20 per cent compared to that deriving from infected cell monolayers. This may be ascribed to a facilitated invasion of host cells by Toxoplasma when the cell's glycocalyx is irritated by trypsinization and to a more far-reaching exploitation of young separated host cells in contrast to cells of monolayers. Moreover, the Toxoplasma trophozoites could be harvested from tissue culture already four days after infection without any change of medium, which makes the method very economical.

Animals↗

PubMed2003

Oat cover cropping and soil insecticides in an integrated sugarbeet root maggot (Diptera: Otitidae) management program.

Sugarbeet, Beta vulgaris L., producers occasionally establish cereal cover crops to minimize early-season soil erosion, wind abrasion, and mechanical injury of seedlings. We evaluated the use of living oat, Avena sativa L., cover cropping as a cultural tactic to minimize feeding injury from sugarbeet root maggot, Tetanops myopaeformis (Röder), larvae at five field sites during 1996, 1998, and 1999. Sweep-net sampling yielded 4.8-, 11.2-, and 7.2-fold more flies from oat cover-cropped chlorpyrifos, terbufos, and untreated control plots, respectively, than in noncover counterparts. However, larval feeding injury in terbufos-treated plots was reduced when cover-cropped (383 seeds/m2) at St. Thomas in all years. A reduced oat seeding rate (224 seeds/m2) also enhanced root protection in terbufos-treated plots at St. Thomas in 1999. Less root injury was sustained in cover-cropped chlorpyrifos plots than in noncover counterparts at St. Thomas in 2 study yr. Oat cover cropping also frequently resulted in reduced T. myopaeformis feeding injury in the absence of a soil insecticide. Although trends toward increased yields were often evident, significant yield benefits were limited to a 6.8% root yield increase in oat cover plots when compared with noncover treatments overall at St. Thomas in 1996 and an 18.4% sucrose yield increase in terbufos-treated plots at St. Thomas in 1999. These findings suggest that beneficial interactions between planting-time soil insecticides and cereal cover crops are achievable in areas infested by T. myopaeformis. Demonstrated reductions in root feeding injury, combined with additional agronomic benefits, may warrant use of this production practice as part of an integrated management program for this key insect pest of sugarbeet.

Agriculture↗

PubMed2002

Enhanced ADP-glucose pyrophosphorylase activity in wheat endosperm increases seed yield.

Yield in cereals is a function of seed number and weight; both parameters are largely controlled by seed sink strength. The allosteric enzyme ADP-glucose pyrophosphorylase (AGP) plays a key role in regulating starch biosynthesis in cereal seeds and is likely the most important determinant of seed sink strength. Plant AGPs are heterotetrameric, consisting of two large and two small subunits. We transformed wheat (Triticum aestivum L.) with a modified form of the maize (Zea mays L.) Shrunken2 gene (Sh2r6hs), which encodes an altered AGP large subunit. The altered large subunit gives rise to a maize AGP heterotetramer with decreased sensitivity to its negative allosteric effector, orthophosphate, and more stable interactions between large and small subunits. The Sh2r6hs transgene was still functional after five generations in wheat. Developing seeds from Sh2r6hs transgenic wheat exhibited increased AGP activity in the presence of a range of orthophosphate concentrations in vitro. Transgenic Sh2r6hs wheat lines produced on average 38% more seed weight per plant. Total plant biomass was increased by 31% in Sh2r6hs plants. Results indicate increased availability and utilization of resources in response to enhanced seed sink strength, increasing seed yield, and total plant biomass.

Glucose-1-Phosphate Adenylyltransferase↗

PubMed1984

Milk yield in rats in relation to activity and size of the mammary secretory cell population.

An attempt was made to partition changes in milk yield during lactation in the rat between changes in the size of the secretory cell population and changes in cellular activity. Groups of rats were studied on d 2, 7, 14, 21 and 28 of lactation. Milk yield increased between d 2 and 7, less markedly between d 7 and 14 and decreased between d 14 and 21. Milk secretion had apparently ceased on d 28. Total mammary DNA (DNAt) and RNA (RNAt) increased from d 2 to 14. It is concluded that of the increase in milk yield between d 2 and 14, an increase in cell population accounted for 75% and an increase in cellular activity for 25%. A decrease in activity appeared to be entirely responsible for the decrease in yield between d 14 and 21.

Animals↗