Tight junctions and mucin mRNA in BEAS-2B cells.
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Bronchi↗
Biomedical subjects
J L Carson
Publications and source records attributed to J L Carson.
Physician malpractice: does the past predict the future?
OBJECTIVE: To assess whether there is a population of physicians who have consistently poor malpractice claims experiences over time. DESIGN: Retrospective cohort study. POPULATION: 12,730 physicians insured in New Jersey from 1977 to 1991. MAIN OUTCOME MEASURES: After adjusting for specialty, the physicians were grouped according to who had the highest, very high, and high rates of malpractice claims, approximating 1%, 5%, and 10% respectively, of the insured population. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated comparing the physicians in these high-risk categories with the other physicians. RESULTS: Of the 55 physicians who had the highest malpractice claims rates during the first four years, two (3.6%) were in the highest group during the subsequent three years (OR 2.8; 95% CI 0.7 to 10.8), five (9.1%) were in the very high group (OR 2.0; 95% CI 0.7 to 5.3), and 11 (20%) were in the high group (OR 2.3; 95% CI 1.1 to 4.6). Of the 260 physicians in the very high group during the first four years, 11 (4.2%) were in the highest group during the subsequent three years (OR 3.6; 95% CI 1.8 to 6.4), 26 (10.0%) were in the very high group (OR 2.3; 95% CI 1.5 to 3.6), and 46 (17.7%) were in the high group (OR 2.0; 95% CI 1.4 to 2.8). Of the 947 physicians in the high group during the first four years, 24 (2.5%) were in the highest group during the subsequent three years (OR 2.3; 95% CI 1.4 to 3.7), 62 (6.6%) were in the very high group (OR 1.5; 95% CI 1.1 to 1.9), and 118 (12.5%) were in the high group (OR 1.3; 95% CI 1.1 to 1.6). Similar results were found when using awards as the outcome. CONCLUSIONS: Most physicians who have high malpractice rates during their first four years improve over time. Physicians who have high rates of malpractice during one period should not be subjected to disciplinary action. However, carefully evaluating physicians who consistently have high rates of malpractice during two periods may represent an effective strategy for identifying problem physicians.
Cohort Studies↗
Is cimetidine associated with neutropenia?
BACKGROUND: Cimetidine is perceived as sufficiently safe that it is being considered for over-the-counter use. However, because of residual concerns about cimetidine-induced neutropenia, a study was conducted to evaluate this association. METHODS: A population-based, case-control study was undertaken using a large database with Medicaid data from six states. Cases were defined as patients hospitalized with a discharge diagnosis of neutropenia. Medical records were sought to validate the diagnoses of neutropenia and to characterize the severity of disease. Four controls were randomly selected for each case, matched for age, sex, state, and year of diagnosis. The frequency of exposures to cimetidine in the 30 days prior to hospital admission in the cases was compared to that in the identical time periods in the controls. RESULTS: When investigators simultaneously controlled for multiple, potentially confounding variables by using conditional logistic regression, the odds ratio associated with the use of cimetidine was 1.2 (P = 0.33), with a one-sided upper 95% confidence limit of 2.6 for all patients over 20 years of age, and 0.6 (P = 0.30) with a one-sided upper 95% confidence limit of 3.1 for validated cases over 12 years of age. Neither a dose-response relationship was evident (P = 0.899 and P = 0.716, respectively, when excluding the nonusers, or P = 0.245 and P = 0.215, respectively, when including the nonusers). From these data, one can exclude the occurrence of hospitalization with neutropenia or agranulocytosis due to cimetidine occurring more often than once in every 116,000 patients and once in every 573,000 patients receiving a 6-week course of the drug, respectively. CONCLUSION: If there is an association between cimetidine and neutropenia, it appears to be very small.
Adolescent↗
Morbidity risk assessment in the surgically anemic patient.
Clinicians have few data on which to base a decision to transfuse a surgical patient. We reviewed animal and human data to evaluate the effects that anemia and comorbidity have on surgical outcome. Experimental evidence consistently demonstrates increased cardiac output, decreased peripheral vascular resistance, and increased release of oxygen by red blood cells in response to anemia. Normal animals tolerate hemoglobin (Hb) levels down to approximately 5 g/dL. Below this level, cardiac ischemia and decreased ventricular function develop. In animals with experimental coronary artery stenosis, cardiac ischemia develops at Hb levels of 7-10 g/dL. Coexisting left ventricular hypertrophy, use of beta blockers, and hypoxemia also reduce animals' ability to tolerate anemia. The limited information on anemia tolerance of human surgical patients suggests that the presence of cardiac and pulmonary disease should influence transfusion decisions. A higher Hb threshold should be used in patients who have or are at risk of cardiac or pulmonary artery disease.
Anemia↗
Variability in distribution and populations of gap junctions in ferret trachea during postnatal development.
Immunocytochemical probes have been used to characterize gap junction distribution in the postnatal ferret trachea by epifluorescence and by laser scanning confocal and electron microscopy. A battery of antibodies directed against fragments of different connexins localized beta 1- and beta 2-gap junction antigens (connexins 32 and 26, respectively) at the intercellular borders of the superficial epithelium while alpha 1-gap junction antigen (connexin 43) was localized to the loose connective tissues. Gap junction labeling in the superficial epithelium declined in the first weeks of life but persisted in the developing submucosal glands to the weanling stage. Localization of the alpha- and beta-antigens was specific for connective tissues and epithelial layers, respectively. These observations suggest that communication competence is an important component of early development in the mammalian airways.
Aging↗
The effect of gastric bypass surgery on hypertension in morbidly obese patients.
BACKGROUND: Hypertension is the most common medical disorder associated with obesity. The relationship between dietary weight loss and the reduction of blood pressure is well established. However, the effect of gastric bypass surgery on blood pressure has not been well studied. METHODS: We evaluated the relationship between weight loss and blood pressure in patients with diastolic hypertension who had gastric bypass surgery for morbid obesity. Patients were defined as hypertensive if taking antihypertensive medication or if both the preoperative office and mean hospital diastolic blood pressures were greater than 90 mmHg. Two of the authors (J.L.C., M.E.R.), blinded to all postoperative weights, classified the follow-up hypertensive status into one of four categories: resolved, improved, no change, or worse. The relationship between postoperative changes in blood pressure status and mean weight loss, percent excess weight loss, and body mass index were examined using a one-way analysis of variance. The relationship between postoperative weight loss and blood pressure was assessed in the baseline normotensive population using linear regression analysis. RESULTS: There were 45 patients with diastolic hypertension; 91% were taking an antihypertensive medication. The mean follow-up was 39 months. The mean preoperative weight was 137 kg and the mean weight loss at 1, 12, and 24 months following surgery was 13, 21, and 45 kg, respectively. Twelve months after surgery, hypertension had resolved in 22 patients (54%) and had improved in six patients (15%). These findings persisted through 48 months postoperatively. There was a significant relationship between the percentage of excess weight lost and improvement of hypertension at the 6-month and 12-month follow-up visits. There was also a significant relationship between the body mass index and improvement of hypertension at the 1-month, 12-month, 24-month, and 48-month follow-up visits. In the baseline normotensive patients there was not a significant relationship between our weight loss measures and changes in blood pressure. CONCLUSIONS: We conclude that postoperative weight loss in patients undergoing gastric bypass surgery was associated with resolution or improvement of diastolic hypertension in approximately 70% of cases. Resolution or improvement of hypertension occurred more often in patients with a lower postoperative body mass index.
Adult↗
Morphogenesis of the murine node and notochordal plate.
Development of the node and formation of the notochordal plate in gestational day 7-9 mice (Theiler stages 10-14) has been documented principally with scanning electron microscopy (SEM) and cell fate analyses utilizing DiI and/or CFSE as a cell label. With SEM, cells composing these two populations are initially identifiable at stage 10 at the ventral midline of the rostral half of the embryo. They can be recognized by their relatively small ventral surface area, as compared to that of the peripherally adjacent prospective gut endodermal cells, and by the presence on the ventral side of each cell of a prominent single, central cilium, which is lacking on endodermal cells. At stage 10, the node is located at the apex of the cup-shaped embryo. It represents the rostral end of the primitive streak (although its structure differs from that of the rest of the streak), and it consists of a localized two-layered area (i.e., epiblast and the most caudal aspect of the notochordal plate). By stage 11, the notochordal plate constitutes a relatively broad, circular area (at the level of the node) that tapers rostrally into a narrower midline strip (beneath the future floor plate of the neural tube). The tip of the notochordal plate terminates rostrally at the much broader prechordal plate, which underlies the future forebrain level of the neuraxis. The prechordal plate cells, like the ventral node and notochordal plate cells, each have a relatively small ventral surface area and displays a single central cilium on their ventral surface. The most caudal aspect of the notochordal plate remains morphologically distinct on the dorsal, midline surface of the open gut through stage 13; the more rostral levels progressively fold off from the roof of the gut to form the definitive notochord. Videomicroscopy reveals that the cilia extending from the ventral surfaces of the cells of node and of the prechordal and notochordal plates are motile. The potential significance of this motile behavior remains unknown. Labeling studies, which marked cells in both the dorsal and ventral layers of the node, reveal that the stage-10 node contributes cells to the notochordal plate and overlying midline ectodermal cells of the neural plate, the future floor plate of the neural tube.(ABSTRACT TRUNCATED AT 400 WORDS)
Animals↗
Current diagnosis and management of sinusitis.
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Acute Disease↗
Bubble hair. Case caused by an overheating hair dryer and reproducibility in normal hair with heat.
BACKGROUND: Bubble hair is an acquired hair shaft deformity characterized by bubble-like areas in the hair shaft seen with light microscopy and corresponding cavitary defects with scanning electron microscopy. OBJECTIVE: Our purpose was to report the fourth case of bubble hair, to demonstrate a cause, and to determine whether the cavities contain gas or liquid. METHODS: Light and scanning electron microscopy were performed. The patient's hair dryer was examined. We applied heat to normal hair of the patient and that of 16 human volunteers. Approximate temperatures for bubble formation were measured. The bubble contents were investigated by applying aqueous and nonaqueous liquids to affected hairs. RESULTS: No person's hair failed to develop bubbles when subjected to sufficient heat. The cause of bubble hair in the patient was an overheating hair dryer. The cavitations contained a gas. CONCLUSION: Bubble hair is a reproducible hair shaft defect caused by heat. The use of overheating hair dryers, or any other hair care equipment that overheats, should be avoided.
Adult↗
Does physician performance explain interspecialty differences in malpractice claim rates?
Physician specialty has been consistently associated with different malpractice claim rates, with neurosurgery, orthopedics, and obstetrics and gynecology having the highest rates. Whether these differences reflect physician performance or other aspects of patient care that are unique for each specialty is unclear. A retrospective cohort study was performed including 12,829 physicians involved in 8,221 closed cases from 1977 to 1991. For each case an assessment was made whether the plaintiff received an award and whether the physician care of the patient was indefensible. An award was made to the plaintiff in 42% of cases. Physician care was considered indefensible in 23% of the cases. The specialties with the highest award rates were anesthesiology (58.3%), obstetrics and gynecology (47.5%), and radiology (43.0%). Neurosurgery had the lowest rate of award (30.2%). The specialties with the highest indefensibility rates were radiology (36%), obstetrics and gynecology (27%), and anesthesiology (27%). Neurosurgery had the lowest indefensibility rate (10%). These results were unchanged after controlling for physician age, degree, site of training, certification status, and severity of patient injury. In conclusion, differences in award rate and indefensibility are present, but not large enough to explain the large variation in specialty claim rates. This suggests that the variation in malpractice rates results from factors other than a meaningful difference in physician performance.
Clinical Competence↗
Epidemiology of gastrointestinal damage associated with nonsteroidal anti-inflammatory drugs.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with significant upper gastrointestinal (GI) toxicity, with a relative risk of approximately 3. This is supported by evidence drawn from randomised controlled trials [of aspirin (acetylsalicylic acid)], cohort studies and case-control studies. The risk is increased with higher doses of medication, shorter treatment duration and concomitant corticosteroid use. Elderly patients and those with a history of GI illness are also at increased risk. Ibuprofen may be associated with a lower, and piroxicam with a higher, risk of complications. There are only preliminary data regarding an association between NSAIDs and small and large intestinal complications. Therapeutic alternatives which may confer a lower risk of significant GI toxicity include enteric-coated preparations, non-acetylated salicylates, and NSAIDs taken in conjunction with misoprostol. Epidemiological data regarding these alternatives are sparse.
Anti-Inflammatory Agents, Non-Steroidal↗
Acute liver disease associated with erythromycins, sulfonamides, and tetracyclines.
OBJECTIVE: To determine whether erythromycins, sulfonamides, and tetracyclines are associated with an increased risk for acute hepatitis. DESIGN: Case-control study. SETTING: Medicaid billing data from Michigan and Florida between 1980 and 1987. PATIENTS: The 107 cases included patients hospitalized with acute symptomatic hepatitis without an identifiable cause of liver disease noted in the medical record. Four controls per case were randomly selected and were matched for age, sex, and state. RESULTS: Five cases (4.7%) and four controls (0.9%) were exposed to erythromycins, yielding an odds ratio of 5.2 (95% Cl, 1.1 to 26.6). No case or control was exposed to erythromycin estolate. Eight cases (7.5%) and three controls (0.7%) were exposed to oral sulfonamides, yielding an odds ratio of 11.4 (Cl, 2.7 to 67.8). All (except one control) had received trimethoprimsulfamethoxazole. Five cases (4.7%) and four controls (0.9%) were exposed to tetracyclines, yielding an odds ratio of 5.2 (Cl, 1.4 to 19.7). The results did not change substantively for erythromycin or sulfonamides after adjustment using multiple logistic regression for age, sex, state, and use of other hepatotoxic drugs. With tetracyclines, however, the odds ratio decreased to 3.6 (Cl, 0.9 to 14.3). Associations were also seen with isoniazid (P = 0.008) and rifampicin (P = 0.04). The number of patients developing acute symptomatic liver disease resulting in hospitalization for each million patients treated with a 10-day course of erythromycin was 2.28 cases; for sulfonamides, this figure was 4.8 cases; and for tetracycline, the figure was 1.56 cases. CONCLUSION: Erythromycin, sulfonamides, and tetracyclines are associated with acute symptomatic hepatitis resulting in hospitalization. Given the widespread use of these drugs, they will be among the more common drugs associated with hepatitis.
Acute Disease↗
Nonsteroidal anti-inflammatory drugs and neutropenia.
BACKGROUND: The association between nonsteroidal anti-inflammatory drugs (NSAIDs) and neutropenia is based primarily on case reports only. METHODS: A population-based, case-control study was performed with Medicaid claims data from six states. Cases were defined as patients hospitalized with neutropenia. Four controls per case were randomly chosen, matched for age, sex, state, and year. The frequency of exposure to NSAIDs in the 30 days before hospital admission in the cases was compared with the frequency in the identical period in the controls. The diagnosis of neutropenia was validated by review of medical records. RESULTS: The crude odds ratio for NSAIDs as a class was 3.3 (90% confidence interval, 1.6 to 6.6). The multivariate adjusted odds ratio was 4.2 (90% confidence interval, 2.0 to 8.7). No single class of NSAID, nor any individual NSAID, was associated with a unique risk, although the data on individual NSAIDs were sparse. Even excluding phenylbutazone and indomethacin, an increased risk was observed (3.5 [1.6 to 7.6]). CONCLUSIONS: Neutropenia is associated with the use of NSAIDs. However, given the low incidence of this disease, the additional number of cases of neutropenia caused by the use of NSAIDs is small. These data do not support the existence of a risk restricted to selected NSAIDs only.
Adolescent↗
Safety of nonsteroidal anti-inflammatory drugs with respect to acute liver disease.
OBJECTIVE: To examine the magnitude of the risk of acute hepatitis associated with the use of nonsteroidal antiinflammatory drugs. METHODS: We calculated the annual incidence rate of hepatitis resulting in hospitalization and then performed a case-control study using 1980 to 1987 Medicaid billing data from Michigan and Florida. The 107 cases included patients with symptomatic acute hepatitis without an identifiable cause of liver disease. Four controls per case were randomly selected and were matched for age, sex, and state. Antecedent drug exposure was assessed 30 days prior to the onset of the disease in the cases and during the same period in the controls. RESULTS: The annual incidence rate (95% confidence interval) of acute idiopathic symptomatic hepatitis resulting in hospitalization was 2.2 (2.0 to 2.4) per 100,000 persons per year. Nine cases (8.4%) and 26 controls (6.1%) were exposed to nonsteroidal anti-inflammatory drugs, yielding an odds ratio of 1.4 (0.6 to 3.1). After adjustment for potential confounding variables, the odds ratio was 1.2 (0.5 to 2.8). CONCLUSIONS: Acute symptomatic idiopathic liver disease severe enough to result in hospitalization is uncommon, and no association was evident between nonsteroidal anti-inflammatory drugs and acute hepatitis. This study was large enough to exclude a relative risk of 2.8. These data suggest that acute symptomatic liver disease from nonsteroidal anti-inflammatory drugs is not a frequent clinical problem.
Abdominal Pain↗
Is a hemoglobin of 10 g/dL required for surgery?
The "10/30" (hemoglobin/hematocrit) rule has long been recognized and accepted in the medical community as the threshold for transfusion in the perioperative setting. However, an increasing number of publications suggest there is no absolute threshold for transfusion, and that this decision should be based on an assessment of the overall clinical picture presented by the patient. This article reviews the risks associated with blood transfusions, and the data in humans and animals that describe the benefits of transfusion. Recommendations on the trigger for red cell transfusion are provided.
Aged↗
Increased adherence of Staphylococcus aureus from cystic fibrosis lungs to airway epithelial cells.
Airway colonization by Staphylococcus aureus is a frequent feature of cystic fibrosis (CF). To assess the pathogenesis of selective colonization with this organism, we compared the capacity of S. aureus isolated from the respiratory tract of CF and non-CF patients to adhere to epithelial cells from the upper and lower airways of CF and control subjects. Bacterial adherence to bronchial epithelial cell lines was significantly greater for CF than for non-CF isolates (p < 0.001). Of 17 CF S. aureus isolates 12 adhered at a level > 1 bacterium per cell; this was true for only 1 of 14 non-CF isolates. CF S. aureus isolates also bound more avidly than non-CF isolates to ciliated (p < 0.05) and squamous nasal cells (p < 0.02) and buccal epithelial cells (p < 0.005) freshly harvested by scraping. Each S. aureus isolate bound with equal avidity to epithelial cells from CF patients and healthy individuals. Adherence was not related to sex, age, severity of pulmonary disease, presence of other microorganisms in the airways, or genotype of the CF hosts. Binding of S. aureus was blocked by proteinase treatment of organisms, suggesting that adherence is mediated by one or more peptide adhesins. We propose that the high prevalence of adherent S. aureus is due either to selection of adherent strains by CF airways or to induction of an adherent phenotype by factors residing at the CF airways surface.
Adolescent↗
Effect of nitrogen dioxide on human nasal epithelium.
The nasal epithelium of young adult white men in good health was evaluated by electron microscopy in a condition blind fashion relative to exposures of 2 ppm nitrogen dioxide (NO2) or clean air for 4 h. The exposure protocol involved two separate exposures of the same individuals to NO2 or clean air approximately 3 wk apart. We found qualitative and quantitative evidence that luminal border membranes of ciliated cells were ultrastructurally altered in six of seven samples of nasal epithelium obtained following NO2 exposures, although subsequent morphometric statistical analyses were not significant. This alteration was characterized by cilia containing excess matrix in which individual or, more commonly, multiple ciliary axonemes were embedded, and by vesiculations of luminal border ciliary membranes, a pattern less common in clean air-exposed control specimens. Although these patterns were not widespread, their morphology was consistent with findings of previous animal studies involving acute and chronic exposure to NO2. Our findings suggest that adverse effects on mucociliary function in normal humans due to acute exposure to low levels of NO2 are most likely minimal. However, in view of other reports of NO2 exposure in laboratory animals documenting ciliary injury, our observations support a view that similar patterns might appear more prominently with higher NO2 levels and/or more extended exposure intervals.
Adolescent↗
Toxicity of nonsteroidal anti-inflammatory drugs. An overview of the epidemiological evidence.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used throughout the world. This paper reviews the epidemiological data linking NSAID administration with gastrointestinal, hepatic, renal, haematological, and hypersensitivity reactions. Meta-analysis has demonstrated that NSAIDs are associated with serious upper gastrointestinal disorders, with a relative risk of 2.7 in patients receiving NSAIDs compared with subjects not receiving NSAIDs. An increase in the dose and duration of NSAIDs and age > 60 are associated with an increase in the risk of upper gastrointestinal toxicity. The current data strongly support a causal relationship between NSAIDs and gastrointestinal disorders. Case-control studies have demonstrated an association between some NSAIDs and neutropenia, with a relative risk of between 3 and 9 in patients treated with NSAIDs compared with nonusers of these drugs. NSAIDs have also been linked with hypersensitivity reactions, although the incidence of such reactions is very low. However, there are inconsistent data on the potential associations between NSAIDs and renal disease, and there are no epidemiological studies linking NSAIDs with acute liver disease. Overall, the incidence of serious adverse reactions associated with NSAIDs is low, and this class of drugs can be regarded as being reasonably safe.
Agranulocytosis↗