Images in cardiology. Perils of polypectomy.
Explore the source record for details and available documents.
Anesthetics, Local↗
Biomedical subjects
P Collier
Publications and source records attributed to P Collier.
Analysis of amelogenin proteins using monospecific antibodies to defined sequences.
Amelogenins are the predominant proteins found in the developing enamel matrix and are believed to play a crucial role in normal mineralization. Although the amelogenin gene is found as a single copy in all species in which it has been examined, multiple amelogenin polypeptides ranging in size from 5 to 25 kDa are obtained upon extraction of developing enamel matrix, making identification and characterization of individual components difficult. This heterogeneity may be ascribed to transcription of divergent genes located on the X and Y chromosomes, alternative splicing of the primary transcripts, physiologic degradative processing, and artefactual degradation. In order to characterize individual components, antibodies were produced to the following peptides: (1) QPLQPMQPMQPLQPLQPL (corresponding to the repeat sequence encoded only in the bovine X chromosome gene), (2) IRHPPLPP (corresponding to a unique sequence generated by alternative splicing found in leucine-rich amelogenin peptide (LRAP), (3) LPDLPLEAWPATDKTKREEVD corresponding to the amelogenin carboxy-terminus. Amelogenin proteins obtained from fetal bovine molars were subjected to SDS PAGE and Western electrotransfer, and immuno-ultrastructural analysis. These analyses demonstrated that: (1) the distribution of amelogenin polypeptides isolated from male fetuses differed appreciably from that of females, (2) the LRAP junctional peptide sequence can be specifically identified, and (3) the LRAP peptide can be immunolocalized in the enamel matrix of both males and females.
Alternative Splicing↗
Analysis of the regulatory region of the bovine X-chromosomal amelogenin gene.
The amelogenin proteins, which are crucial for normal enamel mineral formation, are secreted by ameloblasts during development of tooth enamel. In order to better understand the mechanisms involved in regulation of expression of the amelogenin genes, the bovine X-chromosomal amelogenin gene was cloned and a 3.5 KB fragment upstream of exon 1 was inserted into a beta galactosidase (beta gal) expression vector for production of transgenic mice. When tissues from these mice were treated with Xgal, a substrate for beta gal, only ameloblasts and some of the adjacent stratum intermedium cells contained blue stain. To obtain further information concerning regulation of expression, the 3.5 KB amelogenin gene fragment was evaluated in transfection experiments. Nonoverlapping 1.9 and 1.5 KB fragments of the upstream region were subcloned separately into a vector that contains the SV40 promoter and the CAT reporter gene. Each amelogenin gene fragment was able to suppress CAT activity driven by the heterologous SV40 promoter in transfected HeLa cells. We theorize that each of these gene fragments contains regulatory elements important for the tissue-specific and developmentally-regulated pattern of expression of the X-chromosomal amelogenin gene.
Ameloblasts↗
A team approach to geriatric case management.
Providing high-quality, comprehensive care for elderly Americans is becoming increasingly challenging because of the aging of society, the shortage of primary care physicians, and rising health care costs. These trends are encouraging health care delivery systems to adopt alternative models of patient care. This article reports on one such model, the complementary practice model, which incorporates a team approach to geriatric case management. The complementary practice model targets the frail elderly who are near the end of life, or are at highest risk for either hospitalization or cognitive decline. It includes a diverse, multidisciplinary team to provide patient care by involving the patient, family, physician, nurse practitioner, social worker, and registered nurse as core team members. This team approach assesses and identifies patients' problems, utilizes the expertise of multiple health care disciplines, and encourages patients and families to be active participants in developing and implementing the case management plan.
Aged↗
Compliance with universal precautions and needle handling and disposal practices among emergency department staff at two community hospitals.
BACKGROUND: To describe rates of needle disposal and barrier use within the emergency departments at two privately owned community hospitals in two suburbs of Minneapolis, a study was conducted. This study consisted of direct observation of a cohort of emergency department personnel providing patient care followed by a self-administered survey of the same personnel. METHODS: From June through August 1990, seven specially trained registered nurses observed emergency department personnel for a total of 400 hours. The observers documented the appropriate rates of use of gowns, goggles, masks, and gloves. Observers also noted methods of needle disposal and frequency of needle recapping. After observation, surveys that included items requesting estimates of rates of use for each barrier, as well as estimates of the rates and methods of needle recapping and disposal, were distributed. For each observed and corresponding self-reported behavior, 95% confidence intervals were calculated and compared. RESULTS: A total of 1,822 procedures were recorded. Gloves were observed to be used when appropriate 67.2% of the time, followed by goggles (50.7%), masks (16.0%), and gowns (15.3%). Self-reported barrier rates were slightly higher in all cases except for goggle use. About one third (34.4%) of the needles were recapped; 78.1% of these were recapped two-handed. CONCLUSIONS: Previous studies have documented low universal precautions compliance rates at urban teaching hospitals. Our data indicate less than optimal levels of compliance also at community hospitals, and show that personnel are less than fully aware of their own noncompliance.
Emergency Service, Hospital↗
Variables influencing worker compliance with universal precautions in the emergency department.
BACKGROUND: Emergency department health care workers frequently provide care to patients who are in unstable condition, bleeding, or in a crisis situation. To identify the variables described in the Health Belief Model affecting health care workers' compliance with practices and devices believed to reduce exposure to patients' blood, the staff of a level II trauma center were surveyed for knowledge, compliance, and training regarding universal precautions. METHODS: Fifty-three health care workers responded to an anonymous, self-report, 50-item questionnaire. Significant differences in mean scores were determined by use of a two-tailed t test. RESULTS: Health care workers estimated they were most likely to perform handwashing after contact with body fluids and to wear gloves if contact with blood was anticipated. The most common obstacles to compliance with universal precautions were lack of time, patients perceived to be at lower risk for HIV or hepatitis B infections, and interference with technical skills. Health care workers with more than three perceived obstacles to universal precautions were less likely to use gloves (p < 0.05) if contact with blood was anticipated. Health care workers with a higher number of training experiences in universal precautions were more likely to use gloves if contact with blood was anticipated (p < 0.05) and less likely to recap a needle after giving an intravascular injection (p < 0.05), drawing a blood gas sample (p < 0.05), or injecting medication into an intravenous line (p < 0.05). CONCLUSIONS: The application of the Health Belief Model to this problem suggests that an integrated approach is appropriate. Such an approach should incorporate engineering controls, cognitive approaches, behavior modification strategies, and training experiences to improve skills and dexterity.
Blood-Borne Pathogens↗
A beta-galactosidase expression vector for promoter analysis.
An expression vector plasmid, designated pMCS beta gal, was constructed to contain a multiple cloning site for insertion of gene fragments with potential regulatory function. This plasmid was designed to test promoter activity in transgenic mice, since digestion with Pst I will release all vector sequences, which could inhibit transgene expression in vivo (Jaenisch, 1988). When this vector, containing the amelogenin promoter, was used to make transgenic mice, expression was tissue specific and developmentally regulated similar to the endogenous gene (Chen et al., 1994). In addition, the herpes simplex virus (HSV) thymidine kinase (TK) minimal promoter was inserted into pMCS beta gal to produce pTK beta gal, leaving an Sph I upstream site available for insertion of gene fragments with potential enhancer or silencer function, which can be assayed following transfection into cultured cells.
Animals↗
Linear IgA disease: a heterogeneous disease.
Data from our series of 70 patients support the hypothesis that linear IgA disease is a heterogeneous disease as regards clinical features, target antigens and immunogenetics. The clinical presentation varies as regards age of onset and severity of skin and mucosal involvement and scarring. The use of split skin and of the novel substrate cylindroma has identified 2 target antigens. The majority of patients have a target antigen associated with epidermal cells and possibly cylindroma hemidesmosomes. A minority have a dermal antigen which resembles collagen VII on cylindroma. There is an association with HLA-B8, -DR3, Cw7 and with the linked rare tumour necrosis factor alpha allele, but this is not universal. These differences do not correlate with each other.
Adolescent↗
Linear IgA disease: cylindroma demonstrates heterogeneity of the target antigens.
Serum from 58 patients with linear IgA disease was tested by indirect immunofluorescence on the novel substrate cylindroma, which produces an abundance of basement membrane components. The use of split skin and of cylindroma has identified 2 target antigens. The majority of patients have a target antigen associated with epidermal cells and similar in distribution on cylindroma to hemidesmosome proteins. A minority have a dermal antigen with the distribution of collagen VII on cylindroma. These data support the hypothesis that linear IgA disease is a heterogeneous disease with regard to the target antigens.
Adenoma↗
Molecular overlap of the IgA target antigens in the subepidermal blistering diseases.
Linear IgA disease (LAD) has circulating IgA auto-antibodies which have been found to be associated with epidermal- and dermal-derived antigens. The localization and molecular weight(s) of the IgA target antigen(s) implicated in LAD and their relationship to the target antigens for the IgA antibodies in bullous pemphigoid (BP) and cicatricial pemphigoid (CP) are unknown. Sera from patients with all 3 diseases who had circulating IgA antibodies were studied by immunoblotting with both epidermal and dermal extracts. Our findings indicate that there is heterogeneity in the localization and molecular weights of the target antigen(s), with multiple bands demonstrated with some sera. Three principal target antigens were identified with molecular weights of 110-120, 160-180 and one approximately 285 kD. These antigens were common to all 3 diseases and were found in 25 patients. These results suggest that the target antigens for IgA basement membrane zone antibodies in LAD, BP and CP are multiple, complex in composition and may differ from the conventional BP antigens.
Autoantibodies↗
Fiber-containing formula and needle catheter jejunostomies: a clinical evaluation.
Despite the high frequency of diarrhea, chemically defined diets have traditionally been used with needle catheter jejunostomies, a common form of postpyloric enteral access, to avoid tube occlusion. We reviewed our experience with 57 patients fed a fiber-containing diet to determine the incidence of catheter occlusion and diarrhea. Eight catheters temporarily occluded but were reopened and remained patent for an additional 6.3 +/- 3.1 days for an overall success rate of 91% (52 of 57). The five remaining occluded catheters were removed after 6.2 +/- 1.8 days. Four of the five patients with occluded catheters tolerated gastric feedings, but one required a permanent jejunostomy. Diarrhea occurred in six (10.5%) of the 57 patients given the fiber-containing formula. We concluded that a fiber-containing formula can be administered through needle catheter jejunostomies if the catheter is irrigated daily and if no medications are given via the catheter. A fiber-containing formula may reduce the incidence of diarrhea in jejunostomy-fed patients compared with patients fed chemically defined diets.
Adult↗
The neuropathy of elderly mice.
The aim of this study was to define morphological and neurophysiological features of an age-related neuropathy in mice and to explore possible underlying pathogenetic mechanisms. Teased-fibre analysis of sciatic nerves in aged animals demonstrated a high incidence of demyelination. Electron microscopic analysis of sciatic nerve also revealed axonal atrophy. Both forms of pathology preferentially effect large myelinated fibres. The morphological evidence suggests that demyelination may have resulted from two processes; a primary event and a late consequence of axonal shrinkage. A high-affinity ouabain-binding form of (Na+,K+)ATPase was found in both mice sciatic nerve and spinal roots. A progressive and ultimately severe reduction of enzyme concentration with age was demonstrated in sciatic nerve and dorsal root. Since no change with age was seen in fast (anterograde or retrograde) axoplasmic flow, reduced peripheral nerve (Na+,K+)ATPase is not due to impaired enzyme translocation. Motor nerve conduction velocity decreased significantly with age, while minimum F-wave latency and somatosensory evoked potential latency increased. Impaired conduction velocities in aged animals may be attributed to the interaction of many factors including demyelination, remyelination, a disproportionate loss of large myelinated fibres, axonal atrophy, nerve regeneration and reduced peripheral nerve (Na+,K+)ATPase. It is concluded that the neuropathy in senescent mice is not species specific and is less severe, even in long-lived mice species, compared with that seen in the rat.
Aging↗
Psychological and physiological predictors of lipids in black males.
The association between lipids and both psychological and physiological measures were examined in this study of healthy black males. The results revealed that certain psychological measures, namely, State and Trait Curiosity and Trait Anger, explained a significant proportion of the variance in high-density lipoproteins (HDL), low-density lipoproteins (LDL), and triglycerides. Although psychological factors accounted for a significant proportion of the variance in lipids (29% for HDL, 25% for LDL, 64% for LDL/HDL, 29% for triglyceride), the amount of explained variance was significantly increased by the inclusion of both psychological and physiological variables in the regression equation. However, neither of the psychological variables explained any of the variance for total cholesterol when physiological variables were included in the regression analysis. The overall pattern of the findings suggests that black males who are at increased risk for elevated lipid levels may be identified by their level of mental vigilance, the frequency at which their anger is experienced, and the presence of other traditional risk factors.
Adult↗
Sense of belonging: a vital mental health concept.
Sense of belonging is a concept that has not been researched in psychiatric nursing practice. Using a concept-analysis strategy proposed by Walker and Avant, the authors present a detailed description of the concept that evolved from a series of inductive and deductive strategies. Sense of belonging is defined as the experience of personal involvement in a system or environment so that persons feel themselves to be an integral part of that system or environment. Sense of belonging has important applicability for clinical use as well as continued theory development in psychiatric nursing.
Adaptation, Psychological↗
Improved patient selection for angioplasty utilizing color Doppler imaging.
The accepted approach to patients with intermittent calf claudication is nonoperative unless the symptoms are truly incapacitating, in which case arteriography and either percutaneous angioplasty or operation is indicated. Arteriography is considered a preoperative procedure. However, with improvements in percutaneous angioplasty, we have altered our approach to those patients with limiting, but not incapacitating, claudication. These patients are given the choice of conservative treatment or percutaneous angioplasty, but not operation. In an attempt to limit arteriography to only those patients who would benefit from angioplasty, we have employed color Doppler imaging as a screening technique. Over a 2-year period, 62 patients with limiting claudication were evaluated with color Doppler imaging. Thirty-six patients had long occlusions and did not undergo arteriography since they were not believed to be candidates for percutaneous angioplasty. Three short (less than 5 cm) occlusions and 23 localized stenoses were identified in the superficial femoral and popliteal arteries. Angiography confirmed the Doppler findings in all 26 cases. In 24 patients, dilatation was successful, whereas 2 patients' arteries could not be dilated. Two stenoses recurred early and were redilated. There were no complications from the angioplasties. We conclude that in the subset of patients with limiting, but not incapacitating, claudication, color Doppler imaging can accurately select those patients who will benefit from angioplasty. In this way, patients can be spared unnecessary angiograms.
Angiography↗
Direct approaches to the distal portions of the deep femoral artery for limb salvage bypasses.
This study describes a technique that facilitates lower extremity "redo" revascularizations and that may increase the number of patients who can be revascularized. By using the distal deep femoral artery for bypass outflow or inflow, we were able to revascularize patients with no other accessible patent major thigh artery, to increase the use of autologous vein for infrapopliteal bypasses, and to avoid difficult groin reoperations. Thirty-seven patients (23 men) had various distal deep femoral revascularizations for limb salvage indications only (rest pain, ischemic ulcers, and/or gangrene). Techniques to expose the distal deep femoral artery directly are described and their uses discussed. We found that the type of bypass performed (e.g., axillofemoral or aortofemoral) determined the patency rate of the reconstruction. Placement of the origin or termination of the graft in the deep femoral artery did not appear to affect the results adversely.
Adult↗
Pharmacokinetics and pharmacodynamics of thiazinamium in asthmatic patients.
The pharmacokinetics and pharmacodynamics of thiazinamium (Multergan) were studied after intravenous and intramuscular administration to 7 males with chronic reversible airways obstruction. Disposition after i.v. administration was described by a clearance of 0.54 l.min-1, central compartment volume of 14.8 l, distribution rate constant 0.092 min-1, and an elimination rate constant of 0.0044 min-1. The corresponding estimates after i.m. administration were 0.324 l.min-1, 34.1 l, 0.035 min-1, and 0.0018 min-1. The bronchodilator response (expressed as % predicted FEV1) after i.v. administration was characterized by maximum increase in FEV1 of 33.9%, with an EC50 of 12.8 ng.ml-1 and an equilibration half-time of 11 min. Corresponding parameter estimates after i.m. administration were 32.2%, 18.8 ng.ml-1, and 9 min. Anticholinergic activity, measured by the change in heart rate after i.v. administration, showed maximum increase of 76 beats.min-1, with an EC50 of 176 ng.ml-1 and an equilibration half-time of 1.3 min. After i.m. administration the corresponding values were 120 beats.min-1, 250 ng.ml-1, and 3 min. The optimal plasma concentration of thiazinamium was about 100 ng.ml-1, which should give a near maximal bronchodilator response (over 80% of predicted normal) and a heart rate of about 100 beats.min-1.
Adult↗
Management of the occluded and failing PTFE graft.
Explore the source record for details and available documents.
Arterial Occlusive Diseases↗