PubMed Health⌕ Search

Biomedical subjects

J Pike

Publications and source records attributed to J Pike.

At least 37 records · Page 2Linked to original sources
PubMed1995

A carcinoembryonic antigen polynucleotide vaccine for human clinical use.

We have constructed a plasmid DNA encoding the full-length complementary DNA for human carcinoembryonic antigen (CEA) under transcriptional regulatory control of the cytomegalovirus early promoter/enhancer (pCEA) and demonstrated that this plasmid can function as a polynucleotide vaccine to elicit a CEA-specific immune response. This immune response protects against tumor challenge with syngeneic CEA-transduced colon carcinoma cells in mice. In the present work, the pCEA construct and purification method were modified to eliminate nonessential viral sequences, the ampicillin selectable marker, mutagens, and endotoxin to produce a reagent suitable for human clinical trials. The human use plasmid (pGT37) directs CEA expression at levels comparable with the original pCEA plasmid and can be propagated to yield large quantities of plasmid DNA based on kanamycin selection. A simple extraction technique greatly reduces contamination by endotoxin. Six weekly intramuscular injections of pGT37 elicited CEA-specific lymphoblastic transformation and antibody response in five of five mice and fully protected 10 of 10 mice against tumor challenge with syngeneic CEA-expressing colon cancer cells 42 days from the first plasmid injection. Thus, pGT37 encoding a tumor-associated antigen (CEA) has been shown to elicit cellular and humoral immune responses and mediate antitumor effects in vivo. This plasmid is suitable for human use and can be easily propagated in the laboratory.

Adenocarcinoma↗
PubMed1994

Fractures of the humeral capitellum: Herbert screw fixation.

During the first half of 1991, five patients with displaced fractures of the humeral capitellum were managed by open reduction and fixation of the capitellar fragments with Herbert bone screws. All patients had stable, painfree elbows at follow-up, with no restriction of normal daily activities. There were no evidence of early avascular necrosis of capitellar fragments, even where soft tissue attachments of small fragments had been injured. This method of fixation allows accurate restoration of the articular surface of the humero-radial joint and may therefore contribute to the excellent functional results following this injury in these patients.

Adult↗
PubMed1994

Factor VII antigen levels in a healthy blood donor population.

We determined factor VII antigen (FVIIag) levels in 705 healthy blood donors ranging in age from 17 to 79 years using a two-site solid-phase enzyme immunoassay developed in our laboratory. The mean (+/- SD) FVIIag level for the total population was 102 +/- 31%. FVIIag levels for men (n = 375) and women (n = 330) were 101 +/- 28% and 103 +/- 33%, respectively. A significant increase in FVIIag was observed with age in both men (r = 0.25, p < 0.0001) and women (r = 0.35, p < 0.0001). FVIIag levels were significantly higher in women > 60 years when compared to men (median women: 125%; median men: 111%; p < 0.05). On a subset of the study group (n = 45), FVIIag levels were correlated to total cholesterol (r = 0.27, p = 0.08) and triglyceride (r = 0.41, p < 0.01). Assuming the commonly used reference interval of 60-140% for FVII, the frequencies of FVIIag values for < 60% and > 140% using our assay were 2.1% and 9.2%, respectively. Gender and age-related differences in FVIIag levels must be considered in a reference interval. We further suggest that assay-specific reference ranges be established, which may include values outside the commonly used values of 60-140%.

Adolescent↗
PubMed1993

Leak point of incontinence: a measure of the interaction between outlet resistance and bladder capacity.

A total of 48 consecutive spina bifida patients undergoing routine urodynamic studies was classified into 2 groups depending upon whether they demonstrated uninhibited bladder contractions. Of the patients 34 demonstrated detrusor hyperreflexia and 14 had detrusor areflexia. These 2 groups were then subdivided depending on the continence status. Of the areflexic and hyperreflexic groups, 6 and 7 patients, respectively, were wet despite at least 2 years of conservative medical management. Leak point pressure and leak point volume were determined in all patients and results were compared in both subgroups. In the hyperreflexic groups leak point volume but not leak point pressure was significantly different between the wet and dry patients. The areflexic group demonstrated the opposite finding, that is the leak point pressure but not the leak point volume was significantly different between wet and dry patients. From these studies we determined that in the areflexic group leak point pressure was useful to predict incontinence, whereas in the hyperreflexic group leak point volume was more useful. The addition of the measurement of leak point pressure and leak point volume during routine urodynamic studies in myelodysplastic patients enhances accurate diagnosis and may select those who will best benefit from bladder augmentation and/or a procedure to increase outlet resistance.

Adolescent↗
PubMed1993

Value of bedside plating of semiquantitative cultures for diagnosis of central venous catheter-related infections in ICU patients.

We compared semiquantitative central venous catheter tip cultures plated at the bedside with those cultured in the laboratory, to determine if bedside plating provides a significantly better yield. Paired segments of 197 catheter tips from 92 surgical and medical ICU patients were evaluated prospectively. A total of 31 catheter tip cultures were positive for > or = 15 organisms per agar plate, with 10 of these being simultaneously positive at the bedside and in the laboratory. Cultures were exclusively positive in 18 cases plated immediately at the bedside, whereas laboratory plating resulted in only 3 exclusively positive cases. This discrepancy was statistically significant (p < 0.005). Compared with bedside plating, the sensitivity and specificity of sending catheters to the laboratory were 36 percent and 98 percent, respectively. These results indicate that the practice of sending central venous catheter tips to the laboratory for routine culture should be reconsidered in favor of bedside plating.

Adult↗
PubMed1993

Factor VII assays.

Several prospective and cross-sectional studies have proposed that an association exists between elevated coagulation factor VII levels and cardiovascular disease. Not all of these studies used the same method to assess the factor VII levels. Although the most common method is the one-stage factor assay, there are numerous variables in the composition of this assay. Also, factor VII may circulate in plasma in several forms. The relative contribution of each of these forms to the assay result is presently unknown. Future efforts may help to standardize factor VII assays, improve understanding of the influence of the various forms of factor VII, and identify nonfactor VII components that may both affect assay results and be potential indicators for risk of cardiovascular disease.

Animals↗
PubMed1992

Bactericidal activity of antimicrobial agents against slowly growing Helicobacter pylori.

The doubling times of bacteria at sites of colonization or infection are considerably longer than those in laboratory culture media, and slow growth reduces the susceptibility of bacteria to antimicrobial agents. Helicobacter pylori is susceptible to a wide range of antimicrobial agents in vitro; however, tests for inhibitory activity do not adequately predict which antimicrobial agents will eradicate slowly growing H. pylori from the stomachs of patients. The chemostat can be used to compare the bactericidal activities of antimicrobial substances against slowly growing bacteria. In this study we compared the bactericidal activities of antimicrobial agents against slowly growing H. pylori. The bactericidal activities of erythromycin, minocycline, ampicillin, amoxicillin, cefixime, metronidazole, and bismuth subcitrate against slowly growing H. pylori NCTC 11,637 in a chemostat were compared. Antimicrobial agents were added to the system at four to eight times the MIC. Exposure of H. pylori to metronidazole was associated with the rapid development of metronidazole resistance, preventing assessment of the bactericidal activity of metronidazole. Resistance to the other antimicrobial agents tested did not develop. The poor bactericidal activities of the antimicrobial agents against slowly growing H. pylori may be a contributory factor in limiting their clinical efficacies. Of the agents tested, only amoxicillin and bismuth subcitrate showed bactericidal activity against slowly growing H. pylori. The chemostat allows comparison of the bactericidal activities of antimicrobial agents against slowly growing H. pylori and may therefore provide results which more accurately identify those agents or combinations of agents that will eradicate H. pylori from patients.

Anti-Bacterial Agents↗
PubMed1992

Experience with the AS-800 artificial urinary sphincter in myelodysplastic children.

The authors describe their experience with an artificial urinary sphincter (model AS-800; American Medical Systems, Minnetonka, Minn.) in treating urinary incontinence in children. Twenty-eight sphincters were implanted in 27 boys between May 1986 and June 1989. All the boys had neurogenic bladders secondary to myelomeningocele or sacral agenesis. The mean age at the time of initial implantation was 14 years (range from 9 to 19 years), and the median follow-up was 12 months (range from 6 to 31 months). The sphincters were implanted initially around the bladder neck in 25 cases. Three required reimplantation around the bulbous urethra. The complication rate was 39% (11 of 28 cases). There were two cases of erosion, two cases of infection without erosion and seven cases of device-related problems. The artificial sphincter had to be removed in four cases. There were no deaths. The revision rate was 25% (7 of 28 cases). Continence was evaluated in 22 (88%) of 25 boys who had functional sphincters in place. Five boys required oxybutinin chloride to maintain continence. Ten boys required augmentation cystoplasty before (3), after (6) and combined with (1) sphincter implantation. Eight of these 10 children were able to void spontaneously and were continent. One required intermittent catheterization twice a day and another six times a day. The authors conclude from their experience that the artificial urinary sphincter (model AS-800) can establish continence in boys with neurogenic bladders. Proper selection of the ideal patient for the artificial sphincter is essential to avoid complications.

Adolescent↗
PubMed1989

The blood-brain barrier and response of C.N.S. metastases to chemotherapy.

A case demonstrating a differential effect of chemotherapy on a pineal metastasis and parenchymal cerebral metastases is described. At presentation, extensive metastatic small cell carcinoma of the lung was present and CT scanning showed an apparently solitary metastasis in the pineal. The clinical course and serial CT scans showed significant improvement of the pineal tumor and simultaneous development of multiple intra-cerebral metastases. This case confirms that the pineal gland is excluded from the blood-brain barrier, and indicates the clinical importance of the effect of the blood-brain barrier in the responsiveness of CNS metastases to chemotherapy.

Blood-Brain Barrier↗
PubMed1989

Microcystic adenoma of the pancreas--an incidental finding.

Microcystic adenoma of the pancreas is a rare benign pancreatic tumour usually occurring in elderly females. These tumours have characteristic radiological appearances that should allow their differentiation from the potentially malignant macrocystic adenoma as well as other cystic lesions of the pancreas. A case of a large micro-cystic adenoma of the pancreas found incidentally in a patient with carcinoma of the kidney is presented.

Adenoma↗
PubMed1988

Hemispheric differences for visual evoked potentials from checkerboard stimuli.

Visual evoked potentials (VEPs) were elicited in right-handed male subjects with an alternating checkerboard pattern stimulus presented to either the left or right visual half-field. The sizes of the individual checks in different conditions were 0.25, 0.5, 2.0, or 4.0 cycles/degree of visual angle. The amplitude of the P100 VEP decreased while peak latency increased as check size decreased across both visual field conditions. Left hemisphere responses demonstrated significantly larger P100 amplitudes compared to the right hemisphere responses, although the interaction between hemisphere and stimulus size was not significant. No hemispheric effects of P100 latency were observed. The results suggest that the left hemisphere is engaged more than the right hemisphere for the sensory analysis of visual stimuli composed of straight edges over a wide range of spatial frequencies.

Adult↗
PubMed1985

Detection of Chlamydia trachomatis infection in endocervical specimens using direct immunofluorescence.

A monoclonal antibody specific for Chlamydia trachomatis (Syva MicroTrak) was used to stain endocervical smears from three groups of women. When compared with results from tissue culture, direct specimen results showed 100% (15 of 15) sensitivity and 95% (164 of 172) specificity. The eight specimens with MicroTrak-positive/culture-negative results were probably true positives. Because the direct specimen test method takes less than an hour to complete, is easy to read with a fluorescence microscope, and is much less expensive than culture methods, it could become the rapid screening tool that is urgently needed in young, sexually active women.

Antibodies, Monoclonal↗
PubMed1983

Delayed traumatic intracerebral haematoma: case report.

A case of delayed intracerebral haematoma following closed head injury in a young male is reported. The patient was treated surgically with a satisfactory result. The problem of the unsuspected delayed traumatic intracerebral haematoma is highlighted.

Adolescent↗