PubMed Health⌕ Search

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 73 records · Page 4Linked to original sources

Gene fragment polymerization gives increased yields of recombinant human proinsulin C-peptide.

A multimerization strategy to improve yields upon recombinant production of the 31-aa human proinsulin C-peptide is presented. Gene fragments encoding the C-peptide were assembled using specific head-to-tail multimerization. DNA constructs encoding one, three or seven copies of the C-peptide gene, fused to a serum albumin binding affinity tag, were expressed intracellularly in Escherichia coli. The three fusion proteins were produced at similar levels (approximately 50 mg/l) and were proteolytically stable during production. Enzymatic digestion by trypsin-carboxypeptidase B treatment of the fusion proteins was shown to efficiently release native C-peptide, as determined by mass spectrometry, reverse-phase chromatography and a radioimmunoassay. The quantitative yields of C-peptide obtained from the three different fusion proteins suggest that this multimerization strategy could provide a cost-efficient production scheme for the C-peptide, and that this strategy could be useful also for production of other recombinant peptides.

Amino Acid Sequence↗

Drug-induced alterations in tumour perfusion yield increases in tumour cell radiosensitivity.

The perfusion of human tumour xenografts was manipulated by administration of diltiazem and pentoxifylline, and the extent that observed changes in tumour perfusion altered tumour radiosensitivity was determined. 2 tumour systems having intrinsically different types of hypoxia were studied. The responses of SiHa tumours, which have essentially no transient hypoxia, were compared to the responses of WiDr tumours, which contain chronically and transiently hypoxic cells. We found that relatively modest increases in net tumour perfusion increased tumour cell radiosensitivity in WiDr tumours to a greater extent than in SiHa tumours. Moreover, redistribution of blood flow within WiDr tumours was observed on a micro-regional level that was largely independent of changes in net tumour perfusion. Through fluorescence-activated cell sorting coupled with an in vivo-in vitro cloning assay, increases in the radiosensitivity of WiDr tumour cells at intermediate levels of oxygenation were observed, consistent with the expectation that a redistribution of tumour blood flow had increased oxygen delivery to transiently hypoxic tumour cells. Our data therefore suggest that drug-induced changes in tumour micro-perfusion can alter the radiosensitivity of transiently hypoxic tumour cells, and that increasing the radiosensitivity of tumour cells at intermediate levels of oxygenation is therapeutically relevant.

Animals↗

Use of anaerobically incubated media to increase yield of positive blood cultures in children.

During a 3-year period we received 10024 blood samples for culture from pediatric patients. Overall 181 episodes of significant bacteremia were documented. During the study period we would have missed 35 (19%) of all significant episodes of pediatric bloodstream infections if we had not been using the anaerobically incubated blood bottle. Anaerobically incubated blood samples are also necessary in the pediatric population.

Adolescent↗

Increased yield of ttbb at Hadron Colliders in low-energy supersymmetry.

Light bottom squarks and gluinos have been invoked to explain the b quark pair production excess at the Fermilab Tevatron. We investigate the associated production of ttbb at hadron colliders in this scenario, and find that the rates for this process are enhanced over the standard model prediction. If light gluinos exist, it may be possible to detect them at the Tevatron, and they could easily be observed at the CERN Large Hadron Collider.

Journal Article↗

Increased yield of heterologous viral glycoprotein in the seeds of homozygous transgenic tobacco plants cultivated underground.

The use of transgenic plants in the production of recombinant proteins for human therapy, including subunit vaccines, is being investigated to evaluate the efficacy and safety of these emerging biopharmaceutical products. We have previously shown that synthesis of recombinant glycoprotein B (gB) of human cytomegalovirus can be targeted to seeds of transgenic tobacco when directed by the rice glutelin 3 promoter, with gB retaining critical features of immunological reactivity (E.S. Tackaberry et al. 1999. Vaccine, 17: 3020-3029). Here, we report development of second generation transgenic plant lines (T1) homozygous for the transgene. Twenty progeny plants from two lines (A23T(1)-2 and A24T(1)-3) were grown underground in an environmentally contained mine shaft. Based on yields of gB in their seeds, the A23T(1)-2 line was then selected for scale-up in the same facility. Analyses of mature seeds by ELISA showedthat gB specific activity in A23T(1)-2 seeds was over 30-fold greater than the best T0 plants from the same transformation series, representing 1.07% total seed protein. These data demonstrate stable inheritance, an absence of transgene inactivation, and enhanced levels of gB expression in a homozygous second generation plant line. They also provide evidence for the suitability of using this environmentally secure facility to grow transgenic plants producing therapeutic biopharmaceuticals.

Crosses, Genetic↗

Wrist instability series: increased yield with clinical-radiologic screening criteria.

PURPOSE: To develop screening criteria for patients with wrist pain who have carpal instability. MATERIALS AND METHODS: Data were accumulated retrospectively from the cases of 535 patients with painful wrists (321 male and 214 female patients, aged 11-71 years), who underwent wrist arthrography and wrist instability series between 1979 and 1990. Four screening criteria were evaluated: abnormal carpal alignment on routine radiographs, scapholunate joint or ligament pain, reproducible painful clicking or popping, and positive capitolunate instability pattern. Patients with one or more criteria were assigned to group 1. Patients without any of the criteria were assigned to group 2. RESULTS: Group 1 comprised 142 patients (27%) and group 2 comprised 393 patients (73%). In group 1, 69 (49%) patients had abnormal wrist instability findings, and in group 2, nine (2%) had such findings. All abnormalities in group 2 were depicted on routine arthrograms. CONCLUSION: With use of these screening criteria, the majority of patients with wrist pain do not need to undergo wrist instability series and those that do can undergo a specially tailored series.

Adolescent↗

Increased yield of total RNA from fine-needle aspirates for use in expression microarray analysis.

Fine-needle aspirate samples hold the potential for gaining valuable insight into the molecular details and prognostic indicators for certain types of cancer in a limited volume of relatively pure tumor cells. Although limited, such clinical samples can be used with high efficiency when analyzed in conjunction with gene-dense expression microarrays. For this reason, it is essential to retrieve as much high-quality genetic material as possible from each fine-needle aspirate sample. We have conducted a study to improve the efficiency of extracting high quality total RNA to use in microarray analysis from single ex vivo fine-needle aspirate samples of 11 breast cancers added to RNAlater RNA Stabilization Reagent immediately upon collection. Approximately half the total RNA from fine-needle aspirate samples of breast cancers was isolated from the supernatant, and that RNA had similar quality and gene expression profile to the RNA that was isolated from the corresponding cell pellet. We recommend that the supernatant not be discarded when extracting RNA from fine-needle aspirate samples stored in RNAlater.

Biopsy, Needle↗