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D H Jones

Publications and source records attributed to D H Jones.

At least 109 records · Page 6Linked to original sources
PubMed1993

Genome walking with 2- to 4-kb steps using panhandle PCR.

Panhandle PCR is a method that permits the rapid retrieval of DNA segments flanking a known DNA sequence. This method extends the application of PCR to the retrieval of DNA where only one end of the DNA sequence is known, so that one can use PCR to walk along an uncharacterized stretch of DNA. In this report, we demonstrate that this method can be applied to the highly specific retrieval of large pieces (2.2-4.4 kb) of human genomic DNA that flank the primer annealing sites.

Base Sequence↗
PubMed1993

Caring for hospice patients. In a nursing facility.

Hospices across the nation have successfully developed hospice programs to serve residents in nursing facilities. Three major principles have been identified as key to the programs' success: the nursing facility is considered to be the patient's own home, the nursing facility's staff are the patient's extended family, and that same staff are members of the expanded hospice team.

Contract Services↗
PubMed1993

A method for the amplification of unknown flanking DNA: targeted inverted repeat amplification.

A new method has been developed that permits the rapid amplification of unknown DNA flanking a known site so that one can walk into an uncharacterized region of DNA. This method eliminates the steps and sequence artifacts associated with cloning and permits genome walking into unclonable regions of DNA. In this method, human genomic DNA is restriction enzyme digested and then ligated to the 3' end of a 5'-phosphorylated oligonucleotide using a short bridging oligonucleotide using a short bridging oligonucleotide as a splint. The phosphorylated oligonucleotide is designed to create 5'-end extensions that are complementary to the known sequence. Following denaturation and reannealing under dilute conditions that promote intra-strand annealing and under high stringency, only those DNA strands that contain the known sequence will form a stem-loop structure with a recessed and phosphorylated 5' end. This stem-loop renders a substrate for a subsequent heat-stable ligation reaction to another oligonucleotide that anneals to the known sequence immediately adjacent to the phosphorylated oligonucleotide high-stringency annealing site. The oligonucleotide appended to the phosphorylated oligonucleotide by the heat-stable ligase can, when present in its free, non-ligated form, prime DNA polymerase-mediated amplification of those strands modified by site-specific ligation to this same oligonucleotide. This is followed by one or two nested DNA amplifications, with the final amplification primed by the phosphorylated oligonucleotide in its free, non-ligated form. We successfully applied this method to the specific amplification of 2.2 kb of DNA flanking the 5' end of the cystic fibrosis transmembrane conductance regulator cDNA using primers that anneal to the cDNA sequence and to the specific amplification of 2.2 kb of human genomic beta-globin DNA flanking the primer annealing sites.

Base Sequence↗
PubMed1993

Relative mitogenic activities of wild-type and retinoblastoma binding-defective SV40 T antigens in serum-deprived and senescent human diploid fibroblasts.

A novel gene transfer approach was used to investigate whether the retinoblastoma (Rb)-binding domain of simian virus 40 (SV40) T antigen is required for efficient T antigen-mediated stimulation of DNA synthesis is quiescent or senescent human embryo fibroblasts. In senescent cells, comparison between wild-type T antigen and a mutant defective in Rb binding (Glu-107-->Lys) revealed the latter to have approximately 15-fold lower activity. In contrast, comparison of wild-type and Rb- T antigens in serum-deprived quiescent cells revealed a much smaller (1.8-fold) difference. Surprisingly, an 18-fold differential could be induced by treating quiescent cells with the differentiating agent sodium butyrate. These results suggest that the role of Rb in control of the cell cycle is strongly dependent on the physiological state of the cell and the mechanism of growth arrest.

Antigens, Polyomavirus Transforming↗
PubMed1992

Stability and detection of recombinant pre-pro-concanavalin A after cytoplasmic expression in Escherichia coli.

The cDNA for pre-pro-concanavalin A (pre-pro-Con A) from Canavalia ensiformis was used to construct two cytoplasmic expression vectors: pKconA (no transcription terminator) and pTKconA (containing the cry transcription terminator). The latter produced 2- to 3-fold greater amounts of pre-pro-Con A. This product containing the plant signal can be detected by Western blotting only after electrophoretic transfer in the presence of SDS, indicating reduced solubility. The signal is not removed and pre-pro-Con A is clearly stable after expression in E. coli JM109. The protein is not cleaved and ligated as in the plant, in contrast to a recent report.

Blotting, Western↗
PubMed1992

Cutaneous malignant melanoma, Scotland, 1979-89. The Scottish Melanoma Group.

The Scottish Melanoma Group (SMG) was established in 1979 to assess mortality from and incidence, features, pathological data, and management of cutaneous malignant melanoma in Scotland. Incidence during the first five years and five-year survival have already been reported. We now have data about incidence and mortality over eleven years in relation to anatomical site and pathological types. From 1979 to 1989, 1354 male and 2459 female patients with primary cutaneous malignant melanomas were first diagnosed in Scottish residents. The incidence rate per 100,000 population per year has increased from 3.4 in 1979 to 7.1 in 1989 for men, and from 6.6 to 10.4 for women. The overall increase over eleven years is 82% (7.4% per year). The greatest rates of increase are seen in lesions of the superficial spreading histogenetic type, arising on the female leg and the male trunk. Following public education programmes started in 1985, the proportion of all melanomas less than 1.5 mm thick has shown a sustained and significant increase. Mortality data for 1661 patients for whom a minimum of five-year follow-up is available shows five-year survival of 71.6% overall (77.6% for women, 58.7% for men). The survival advantage for women persists when appropriate statistical adjustment is made for thickness, ulceration, and histogenetic type. These data are useful in designing public education programmes aimed at both primary and secondary prevention of melanoma and in auditing changes in trends that might result from such education.

Adolescent↗
PubMed1992

Sequence specific generation of a DNA panhandle permits PCR amplification of unknown flanking DNA.

We present a novel method for the PCR amplification of unknown DNA that flanks a known segment directly from human genomic DNA. PCR requires that primer annealing sites be present on each end of the DNA segment that is to be amplified. In this method, known DNA is placed on the uncharacterized side of the sequence of interest via DNA polymerase mediated generation of a PCR template that is shaped like a pan with a handle. Generation of this template permits specific amplification of the unknown sequence. Taq (DNA) polymerase was used to form the original template and to generate the PCR product. 2.2 kb of the beta-globin gene, and 657 bp of the 5' flanking region of the cystic fibrosis transmembrane conductance regulator gene, were amplified directly from human genomic DNA using primers that initially flank only one side of the region amplified. This method will provide a powerful tool for acquiring DNA sequence information.

Base Sequence↗
PubMed1992

Non-glycosylated recombinant pro-concanavalin A is active without polypeptide cleavage.

The complex post-translational processing of concanavalin A (Con A) in maturing jackbeans is unique because the non-glycosylated mature active protein is circularly permuted in primary sequence relative to its own inactive precursor (glycosylated pro-Con A) and to other legume lectins. We show here that non-glycosylated pro-Con A expressed in bacteria from recombinant cDNA (rec-pro-Con A) folds in vivo and in vitro to a stable form which is active without further processing. N-glycosylation alone must therefore be sufficient to inactivate pro-Con A--a novel role for glycosylation in regulating activity during protein maturation.

Base Sequence↗
PubMed1992

Living arrangements, knowledge of health risks, and stress as determinants of health-risk behavior among college students.

The association of knowledge of health risks, living arrangements, and perceived stress with health-risk behaviors was examined in a sample of college students included in the Health Promotion and Disease Prevention Supplement of the National Health Interview Survey. Regressions of each health-risk behavior (dependent variable) were performed on the predicted correlates. Although knowledge was not associated with participation in physical activity or smoking, the study found that students who knew more about the harmful effects of alcohol drank less, and those with greater knowledge of health risks practiced fewer risky behaviors. Students living independently were more likely to smoke, and those living in residence halls were less like to do so. Drinking, however, was more common among students living in residence halls or independently than among those living at home. Hall residents engaged in more group physical activity than other students did, but their physical activity was unrelated to health-risk behaviors. Stress was associated with smoking but not with other health practices. The findings suggest that smoking may be less influenced by health knowledge and more associated than drinking is with a response to stress. Drinking appears to be a social activity associated with living among peers and is potentially modifiable by increased knowledge about the effects of alcohol on health.

Adolescent↗
PubMed1992

Nucleotide sequence of the structural gene encoding a 2-haloalkanoic acid dehalogenase of Pseudomonas putida strain AJ1 and purification of the encoded protein.

The nucleotide sequence of a gene encoding an L-2-haloalkanoic acid halidohydrolase from Pseudomonas putida strain AJ1 was determined. The ORF (hadL) codes for a polypeptide of 227 amino acids (Mr 25,687) which has significant homology to two other L-2-haloalkanoic acid halidohydrolases of Pseudomonas sp., DehcI and DehcII; these show 38% and 51% amino acid identity respectively to HadL. All three enzymes produce products of an opposite optical configuration to that of the substrates. Comparison of the three sequences shows several highly conserved motifs which indicate the possible position of the enzyme active site. The enzyme was purified to homogeneity and appears to exist as a tetramer.

Amino Acid Sequence↗
PubMed1992

Recombinant circle PCR and recombination PCR for site-specific mutagenesis without PCR product purification.

Two simple methods for site-specific mutagenesis are described and compared. In each method, the PCR is used in two separate amplifications to mutate the site of interest and to add ends to one PCR product that are homologous to the ends of the other PCR product. In the first method, the two products are combined, denatured and reannealed prior to transformation of E. coli in order to form recombinant circles in vitro, while in the second method, the two linear products are co-transfected directly into E. coli without prior manipulation, resulting in transformation of E. coli with the recombinant of interest by recombination in vivo. Each PCR amplification uses a plasmid template that has been linearized by restriction enzyme digestion outside the region to be amplified. This permits use of unpurified PCR products in these two protocols and generation of the mutant of interest with no other enzymatic manipulation in vitro apart from PCR amplification. In each protocol greater than or equal to 50% of the resulting clones contained the mutation of interest without detected errors.

Base Sequence↗
PubMed1991

Cardiovascular health knowledge in the United States: findings from the National Health Interview Survey, 1985.

Knowledge of the risk precursors to cardiovascular disease is thought to be a key component of health decision making. Many intervention programs have been aimed at increasing the nation's general knowledge of risk factors for cardiovascular disease, although the determinants of the level of cardiovascular disease knowledge are not thoroughly understood. We examined cardiovascular knowledge in a nationally representative sample of the United States population with data from the 1985 Health Promotion and Disease Prevention supplement of the National Health Interview Survey. Interviews with 12,551 white women, 770 Hispanic women, 2,547 black women, 9,832 white men, 576 Hispanic men, and 1,440 black men were used in this analysis. We constructed a seven-item index for cardiovascular disease knowledge. After adjustment for age and education, white men and women scored higher on the cardiovascular disease knowledge index than either their Hispanic or black counterparts. We also examined the relationships of age, education, income, marital status, access to medical care, geographic region, and seven self-reported cardiovascular disease risk factors to the levels of cardiovascular disease knowledge. Education was the strongest predictor of cardiovascular disease knowledge. The variables examined accounted for a small portion of the variance in knowledge. Levels of cardiovascular disease knowledge were lower among respondents with less education and income, those who were not married, those with less access to medical care, and those who were smokers or physically inactive. Therefore, efforts to improve levels of cardiovascular disease knowledge should be directed toward subgroups.

Age Factors↗
PubMed1991

Successful use of subcutaneous recombinant human erythropoietin before cholecystectomy in an anemic patient with religious objections to transfusion therapy.

Use of recombinant human erythropoietin has been advocated for therapy in anemic patients with end-stage renal disease and to enhance the harvesting of autologous red blood cells from healthy patients scheduled for elective orthopedic surgery. The authors report the case of a diabetic patient with moderate chronic renal failure and cholelithiasis but whose religious beliefs forbade the use of transfusion therapy. She underwent successful cholecystectomy only after treatment with recombinant human erythropoietin.

Anemia↗
PubMed1991

A rapid method for recombination and site-specific mutagenesis by placing homologous ends on DNA using polymerase chain reaction.

We have developed a novel polymerase chain reaction (PCR) method that permits the rapid generation of site-specific mutants and recombinant DNA constructs with a minimum number of steps and primers. DNA segments are modified by using amplifying primers that add homologous ends to the polymerase chain reaction product(s). These homologous ends undergo recombination in vivo following transformation of recA-E. coli strains used routinely in cloning. In vivo circularization of PCR products containing plasmid sequences with a selective marker permits the rapid cloning of the desired mutant or recombinant. In the mutagenesis protocol, 7 of the 12 clones contained the product of interest, and 6 of these clones had no detected error (50% of the clones without detected errors). In each of several recombination protocols, at least 50% of the clones tested contained the insert of interest without detected errors.

Base Sequence↗
PubMed1991

Fluid therapy in the PACU.

The goal of fluid therapy in the PACU setting is the restoration of blood volume and tissue perfusion. Choosing the type of fluid infusion depends on the preoperative, intraoperative, and postoperative condition of the patient. An understanding of the functional fluid compartments, the composition of body fluids and commercially available fluids, and the steps to evaluate fluid depletion allow one to determine the fluid needs of the patient. The orderly and expedient evaluation of fluid status of the postoperative patient involves the assessment of volume status, concentration status, composition status, and signs and symptoms of inadequate tissue perfusion. Recovery after surgery is a dynamic process, and fluid reassessment should be conducted periodically. Fluid challenges may be necessary in the hypovolemic patient or in patients with clear signs and symptoms of end-organ hypoperfusion. Weil and Rackow and Shoemaker provide useful approaches to fluid challenge guided by CVP and PAP monitoring. The decision of whether to use crystalloids or colloids for fluid resuscitation is complex, controversial, often determined by personal preference and concern over expense, and may be inconsequential as long as fluids are infused appropriate to the needs of the patient. There are disadvantages and advantages to both crystalloid and colloid fluid administration. As with any therapeutic intervention, there are complications with fluid administration, congestive heart failure and pulmonary edema being of more immediate concern. Finally, blood components are colloid-type solutions that should be reserved for specific patient problems. Red blood cells are indicated to increase oxygen-carrying capacity in patients with anemia. Platelets are used to treat bleeding associated with deficiencies in platelet number or function. Fresh frozen plasma is transfused to increase clotting factor levels in patients with demonstrated deficiency. A good understanding of fluid types available, of a systematic approach to evaluating fluid depletion, and of the indications for blood component therapy will allow one to make appropriate decisions when implementing fluid therapy in the PACU.

Blood Transfusion↗