Biomedical subjects
Publications and source records attributed to D Gordon.
Presence of gas in the prosthetic graft bed does not necessarily represent infection, but may rather be indicative of the presence of benign gas. The diagnostic and therapeutic implications of this finding are discussed.
In a young woman with POEMS syndrome and two systemic embolic events, transesophageal echocardiography revealed a small mobile aortic valve mass. At surgery, an aortic valvular papillary fibroma, with areas of attached thrombus, was removed. This case underlines the importance of transesophageal echocardiography in identifying cardiac sources of emboli.
We describe a unique case of a left coronary arteriovenous fistula arising from a left sinus of Valsalva aneurysm in a pregnant woman. The relevant diagnostic contributions of two-dimensional echocardiography, color flow Doppler, magnetic resonance imaging, and angiography are discussed. The hemodynamic manifestations of this anomaly in pregnancy and the eventual surgical correction are reviewed.
In this descriptive study, healthcare needs reported by 386 HIV-infected persons from all risk categories and their primary nurses from four care settings (hospital, outpatient, long-term care, and home) are identified. Healthcare needs were classified into four domains of nursing practice using a conceptual framework from community health nursing--physiologic, psychosocial, health behaviors, environmental--and were assessed using the Healthcare Needs Scale for Patients with HIV/AIDS. Nurses' perceptions of major healthcare needs across all settings centered around decreased physical endurance, limited physical mobility, and sensory deficits. Patients' needs focused on financial issues. The results reflect the multidimensional nature of this infection and provide direction for clinical practice.
Culture expansion of fetal cells from the maternal circulation will provide an increased number of cells for non-invasive prenatal diagnosis. Hematopoietic CD34+ cells are potential candidates for this application. More information is needed regarding the frequency of these cells and the phenomenon of post-delivery persistence in the maternal circulation. In this study we assessed the number of fetal CD34+ cells in the maternal circulation, the effect of culture expansion on the number of fetal cells and the persistence of fetal CD34+ cells from previous pregnancies. Fetal cells were identified by the presence of Y-chromosome sequences detected by FISH and nested PCR. Fetal CD34+ cells were detected in all samples from women carrying a male fetus. A low number of residual fetal cells from previous pregnancies was detected (1-3 XY cells in 20 ml blood) in less than 1/3 of the samples from both non-pregnant women and those pregnant with a female fetus. Culturing of CD34+ cells resulted in a significant increase in fetal cell numbers. However, the number of fetal cells persisting from previous pregnancies also increased after culture. It is proposed that information derived from CD34+ cells could potentially support data derived from other cell types for more accurate non-invasive prenatal diagnosis.
Yersinia pestis, the etiologic agent of plague, is endemic in the western United States; 105 cases were reported between 1970 and 1979. Plague may manifest in one of three clinical forms; bubonic, septicemic, or pneumonic. Bubonic and septicemic plague represent relatively little risk for human-to-human transmission to contacts, although heavily infected secretions, such as drainage from a bubo, pose a theoretical risk, especially if they are aerosolized from a syringe during diagnohree clinical forms; bubonic, septicemic, or penumonic. Bubonic and septicemic plague represent relatively little risk for human-to-human transmission to contacts, although heavily infected secretions, such as drainage from a bubo, pose a theoretical risk, especially if they are aerosolized from a syringe during diagnohree clinical forms; bubonic, septicemic, or penumonic. Bubonic and septicemic plague represent relatively little risk for human-to-human transmission to contacts, although heavily infected secretions, such as drainage from a bubo, pose a theoretical risk, especially if they are aerosolized from a syringe during diagnostic aspirations. Pneumonic plague may be highly contagious to contacts and poses a greater risk. The Plague Branch, Center for Disease Control recommends that all patients with plague be placed in strict isolation for the first 48 hours of treatment because of the possibility that pneumonia may supervene. If it does not, wound and skin precautions are adequate for the duration of hospitalization. Untreated plague pneumonia is an epidemiologic emergency. All contacts must be identified promptly and those with face-to-face exposure should receive abortive antibiotic therapy. All contacts should be under surveillance, with twice-daily temperature checks, for seven days.
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A threshold of 3.3 for a genome-wide maximum LOD score (MAXLOD) has been demonstrated in human linkage studies as corresponding to a type I error rate of 5%. Generalization of this work to other species assumes the presence of an infinitely dense marker map. While this assumption is increasingly realistic for the human genome, it may be unrealistic for the dog genome. In this study we establish the analytic and empirical thresholds for MAXLOD in canine linkage studies corresponding to type I error rates of 5% and 1% for autosomal traits. Empirical thresholds are computed via simulation assuming a 10 cM map with no fine mapping performed. Pedigree structures for simulations were drawn from two canine disease studies. Five thousand replicates of genome-wide null genotype data were simulated and analyzed for each disease. We determined that MAXLOD thresholds of 3.2 and 2.7 correspond to analytic and empirical type I error rates of 5%, respectively. In all cases, the MAXLOD thresholds from simulations were always at least 0.5 LOD units below the corresponding analytic thresholds. We therefore recommend that a threshold of 3.2 be used for canine linkage studies when fine mapping is performed, and that researchers perform their own simulation studies to assess genome-wide empirical significance levels when no fine mapping is performed.
The effect of altering the frequency of self-monitoring of blood glucose upon blood glucose control was assessed in 25 Type 1 diabetic patients. Patients entered a balanced, crossover study in which they were randomly allocated to three 12-week periods. During each period the frequency at which patients self-monitored their blood glucose was: (1) four-point profiles on 2 days per week; (2) four-point profiles on 1 day per week; (3) two-point profiles on every day of the week. There were no significant differences in mean blood glucose concentration, fructosamine or glycosylated haemoglobin concentrations during the three periods. There was no correlation between the frequency at which patients altered insulin doses and measures of metabolic control. Altering the frequency of blood glucose self-monitoring had a variable and uncertain influence upon the frequency at which patients altered insulin doses. Some patients felt unsafe monitoring blood glucose only four times per week. There was however no patient consensus on the best-liked regimen.
The fibrillin gene (FBN1) is the disease locus for Marfan syndrome. This disorder shows a high degree of clinical and allelic heterogeneity. Direct mutation screening has proven difficult and inefficient and at present cannot be utilized for routine analysis. In familial cases linkage analysis represents a useful tool for molecular diagnosis. We have determined the allelic frequencies of 5 polymorphic markers within the FBN1 locus in the Italian population and have successfully employed them for prenatal diagnosis and resolution of clinically equivocal cases.
We have used a double-immunolabelling technique on human carotid atherosclerotic plaques to measure cell proliferation and type-I collagen gene expression, using antibodies to proliferating cell nuclear antigen (PCNA) and type-I procollagen protein, respectively. Although cell proliferative activity and type-I collagen gene expression can occur simultaneously in the same cell, this is a rare event, and the vast majority of collagen-producing cells do not show proliferative activity. These two processes also tend to occur in separate locations, although they can coexist in certain regions of the plaque. This disparate location of these two important modes of plaque growth suggests that cell proliferation and collagen gene expression may be under separate biological controls during the development and evolution of human atherosclerosis.
A retrospective study of 15 Mitchell and 15 Chevron osteotomies was undertaken in order to compare the efficacy of these two procedures in the correction of hallux valgus. Patient satisfaction, clinical findings, and roentgenographic measurements were all carefully evaluated after follow-up periods of 21 +/- 5 months for the Chevron and 34 +/- 8 months for the Mitchell procedures. Differences observed were a better correction of the angle between the first and second metatarsals by the Mitchell osteotomy (2.3 vs 5.5 degrees) and a tendency to loose the correction in the immediate postoperative period for the Chevron osteotomy. However, no clinical superiority could be demonstrated, nor did patient satisfaction differ in the two techniques. The authors conclude that these procedures give essentially equivalent results. Although the outcome was generally considered satisfactory by the patient, nearly 40% of both groups had metatarsalgia in the lateral rays, which stresses the importance of carefully considering load distribution across the foot in planning any corrective surgery.
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Computer-based voice-recognition software has many potential advantages in producing reports of radiology procedures. Using voice-recognition systems, however, necessitates increased involvement of the radiologist in the process of producing the report. The radiologist, previously responsible only for recording a report onto tape and ensuring the integrity of the final report now becomes obligated to interact with the computer and to ensure the integrity of the transcription process as well as the accuracy of the final report. Two attending radiologists and one first-year radiology resident at an academic medical center timed the production of reports using both the voice recognition system and tape transcription of reports of plain films (n = 27), mammograms (n = 25), and GI/GU exams (n = 17). In addition, the taped dictations were transcribed and then corrected by the physicians. The additional correction time (determined as an average) was added to the tape times to produce a "corrected" tape time. Paired T-Test procedures were used to determine if pairs of readings (voice recognition vs. corrected tape transcription) differed in length of time. In addition, the data was stratified into three groupings--plain film, mammography, and GI/GU--in order to assess for differences between modalities. The length of time required to produce a radiology report using the commercial radiology voice recognition system employed at our center is significantly longer than that required by the traditional corrected tape transcription system. One motivation to use a voice recognition system is the cost savings achieved by eliminating transcriptionists and replacing them with the radiologist using the voice recognition system. In our institution this cost savings is estimated to be $100,000 annually. This apparent cost savings is reduced by the cost of the lost productivity of the radiologist. Compared to tape transcription, our data demonstrate a significant increase in the amount of time necessary for radiologists to produce a radiology report when using the voice recognition system currently employed in our hospital. While it is likely that future systems will require less extra time, this factor needs to be accounted for when departments consider using such systems to replace transcriptionists with radiologists.
PURPOSE: Zoledronic acid, a new and more potent bisphosphonate, was compared with pamidronate, the current standard treatment for patients with osteolytic or mixed bone metastases/lesions. PATIENTS AND METHODS: A total of 1,648 patients with either Durie-Salmon stage III multiple myeloma or advanced breast cancer and at least one bone lesion were randomly assigned to treatment with either 4 or 8 mg of zoledronic acid via 15-minute intravenous infusion or 90 mg of pamidronate via 2-hour intravenous infusion every 3 to 4 weeks for 12 months. The primary efficacy endpoint was the proportion of patients experiencing at least one skeletal-related event over 13 months. RESULTS: The proportion of patients with at least one skeletal-related event was similar in all treatment groups. Median time to the first skeletal-related eventwas approximately 1 year in each treatment group. The skeletal morbidity rate was slightly lower in patients treated with zoledronic acid than in those treated with pamidronate, and zoledronic acid (4 mg) significantly decreased the incidence and event rate for radiation therapy to bone, both overall and in breast cancer patients receiving hormonal therapy. Pain scores decreased in all treatment groups in the presence of stable or decreased analgesic use. Zoledronic acid (4 mg) and pamidronate were equally well tolerated; the most common adverse events were bone pain, nausea, fatigue, and fever and < 5% of serious adverse events were related to the study drug. The incidence of renal impairment among patients treated with 4 mg of zoledronic acid via 15-minute infusion was similar to that among patients treated with pamidronate. CONCLUSIONS: Zoledronic acid (4 mg) via 15-minute intravenous infusion was as effective and well tolerated as 90 mg of pamidronate in the treatment of osteolytic and mixed bone metastases/lesions in patients with advanced breast cancer or multiple myeloma. (Can-
An infiltration of mononuclear leukocytes into the myocardium of a cardiac allograft is diagnostic of transplant rejection. The presence of these leukocytes implies their adhesion to, and subsequent migration through, the vascular endothelium. Intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 are endothelial proteins that have been shown to be involved in the binding of mononuclear leukocytes to the endothelium in vitro. We investigated the induction of these proteins in a random series from 99 endomyocardial biopsy specimens obtained from 1 week to 4 years after cardiac allograft transplantation. Intercellular adhesion molecule-1 was found to be expressed constitutively by the myocardial microvasculature in the recipient's original heart and in the posttransplantation biopsy specimens. No correlation was found between the presence or absence of intercellular adhesion molecule-1 expression and cellular rejection. In contrast, no endothelial expression of vascular cell adhesion molecule-1 was observed in the recipient heart or in endomyocardial biopsy specimens lacking cellular rejection. The presence of vascular cell adhesion molecule-1 significantly correlated with the presence of mild or moderate rejection. The de novo induction of vascular cell adhesion molecule-1 on the myocardial vasculature during periods of rejection, in addition to the recruitment of mononuclear leukocytes that are known to bind to this protein, suggests that the expression of this endothelial adhesion protein could be of use in diagnosing rejection.