PubMed Health⌕ Search

Biomedical subjects

L M Lucas

Publications and source records attributed to L M Lucas.

At least 19 recordsLinked to original sources
PubMed2001

Comparative pathogenesis of tissue culture-adapted and wild-type Cowden porcine enteric calicivirus (PEC) in gnotobiotic pigs and induction of diarrhea by intravenous inoculation of wild-type PEC.

Porcine enteric calicivirus (PEC/Cowden) causes diarrhea in pigs, grows in cell culture, and is morphologically and genetically similar to the Sapporo-like human caliciviruses. Genetic analysis revealed that the tissue culture-adapted (TC) Cowden PEC has one distant and three clustered amino acid substitutions in the capsid region and 2 amino acid changes in the RNA polymerase region compared to wild-type (WT) PEC (M. Guo, K.-O. Chang, M. E. Hardy, Q. Zhang, A. V. Parwani, and L. J. Saif, J. Virol. 73:9625-9631, 1999). In this study, the TC PEC, passaged in a porcine kidney cell line, and the WT PEC, passaged in gnotobiotic (Gn) pigs, were used to orally inoculate 13 4- to 6-day-old Gn pigs. No diarrhea developed in the TC-PEC-exposed pigs, whereas moderate diarrhea developed in the WT-PEC orally inoculated pigs, persisting for 2 to 5 days. Fecal virus shedding persisting for at least 7 days was detected by both reverse transcription (RT)-PCR and antigen-enzyme-linked immunosorbent assay (antigen-ELISA) in both TC-PEC and WT-PEC orally inoculated pigs but not in mock-inoculated pigs. The PEC particles were detected by immunoelectron microscopy (IEM) in intestinal contents from all the WT-PEC-inoculated pigs, but not from the TC-PEC-inoculated pigs. Mild (duodenum and jejunum) or no (ileum) villous atrophy was observed in histologic sections of the small intestines of TC-PEC-inoculated pigs, whereas WT PEC caused mild to severe (duodenum and jejunum) villous atrophy and fusion. Scanning electron microscopy confirmed mild shortening and blunting of villi in the duodenum and jejunum of the TC-PEC-inoculated pigs, in contrast to moderate to severe villous shortening and blunting in the duodenum and jejunum of WT-PEC-inoculated pigs. Higher numbers of PEC antigen-positive villous enterocytes were detected by immunofluorescent (IF) staining in the proximal small intestine of the WT-PEC-inoculated pigs, in contrast to low numbers of PEC antigen-positive enterocytes in only one of four TC-PEC-inoculated pigs. No PEC antigen-positive cells were observed in the colon or extraintestinal tissues of all inoculated pigs or in the small intestine of one mock-inoculated pig. Thus, the TC PEC was at least partially attenuated (no diarrhea, mild lesions) after serial passage in cell culture. In further experiments, three 4- to 6-day-old Gn pigs were intravenously (i.v.) inoculated with WT PEC, and all pigs developed diarrhea and villous atrophy in the small intestines resembling that observed in the orally inoculated pigs. Fecal viral shedding persisting for 8 days was detected by both RT-PCR and antigen-ELISA, and PEC was detected by IEM in feces or intestinal contents. The PEC RNA and antigens (at low titers) were detected in acute-phase sera from all the WT-PEC i.v.-inoculated pigs and also from seven of nine of the WT-PEC orally inoculated pigs. Oral or i.v. inoculation of four additional pigs with the PEC-positive acute-phase sera induced diarrhea, small intestinal lesions, PEC shedding in feces, and seroconversion to PEC, confirming the occurrence of viremia during PEC infection, with infectious PEC present in acute-phase sera. No diarrhea, histopathologic changes, or IF staining in the small intestine or fecal or serum detection of PEC was evident in two pigs i.v. mock-inoculated or a pig inoculated i.v. with inactivated WT PEC. To our knowledge, this is the first report of an attenuated enteric calicivirus, the induction of diarrhea, and intestinal lesions in Gn pigs caused by i.v. inoculation of WT PEC and the presence of viremia following PEC infection.

Animals↗
PubMed1995

Sinusitis. A review for generalists.

A frequent complication of the common cold, sinusitis is one of the most prevalent problems seen in general medical and emergency department practices. In addition, nosocomial sinus infection, particularly in intensive care units, is being recognized more frequently. Decision making about managing patients with sinusitis is based primarily on the history and, to a lesser extent, the findings of the physical examination.

Diagnosis, Differential↗
PubMed1993

Polypharmacy: the cure becomes the disease.

Polypharmacy occurs when a medical regimen includes at least one unnecessary medication. Factors that contribute to this problem include: patient characteristics of increasing age, multiple medical problems, therapy expectations, and decisions to self-treat; physician factors such as excessive prescribing; and system problems of multiple providers and lack of a coordinating provider. Complications include increased adverse drug reactions and noncompliance, which can lead to increased hospitalization and associated costs. Polypharmacy can be avoided by patient education and sharing the decisions for making the treatment goals and plan. The medication regimen can be simplified by eliminating pharmacologic duplication, decreasing dosing frequency, and regular review of the drug regimen. The goal should be to prescribe the least complex drug regimen for the patient as possible, while considering the medical problems and symptoms and the cost of therapy.

Aged↗
PubMed1992

Case report: multisystem failure following intravenous iopamidol.

A case of life-threatening adverse effects following intravenous administration of a non-ionic contrast medium is reported. The patient, a 68-year-old diabetic hypertensive male with dyspnoea and cough had an abnormal chest radiograph, revealing congestive heart failure and an enlarged right hilum. Computed tomography (CT) of the chest was performed using 100 cm3 of intravenous iopamidol. Within half an hour the patient developed abdominal cramping, vomiting, and diarrhoea, followed by hypotension, tachycardia, fever to 40 degrees C, and delirium. His course was complicated by disseminated intravascular coagulation, rhabdomyolysis, renal failure, respiratory arrest, and atrial fibrillation. There was no evidence of infection, neoplastic disease, or myocardial infarction. Over the next month the patient slowly recovered. One other case report implicates a contrast agent with a similar syndrome. The features of this case fulfil the criteria for a probable adverse drug reaction of a type and severity rarely encountered.

Aged↗
PubMed1992

Recognizing and reporting adverse drug reactions.

Although physicians in practice are most likely to see patients with adverse drug reactions, they may fail to recognize an adverse effect or to attribute it to a drug effect and, when recognized, they may fail to report serious reactions to the US Food and Drug Administration (FDA). To recognize and attribute an adverse event to a drug effect, physicians should review the patient's clinical course, looking at patient risk factors, the known adverse reactions to the suspected drug, and the likelihood of a causal relationship between the drug and the adverse event-based on the temporal relationship, response to stopping or restarting the drug, and whether other factors could explain the reaction. Once an adverse drug reaction has been identified, the patient should be informed and appropriate documentation made in the patient's medical record. Serious known reactions and all reactions to newly released drugs or those not previously known to occur (even if the certainty is low) should be reported to the FDA.

Adult↗
PubMed1992

Clinical significance in alcoholic patients of commonly encountered laboratory test results.

An improved understanding of medical problems of alcoholic patients can be gained from commonly encountered laboratory test results. Liver function tests--such as measures of alkaline phosphatase, gamma-glutamyl transpeptidase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase--may provide evidence of altered hepatic activity of different types, such as obstruction and hepatocellular injury. Other test results may indicate impaired hepatic function, such as measurements of albumin, bilirubin, prothrombin time, and blood urea nitrogen. Alterations are also common in electrolytes, blood glucose, magnesium, phosphate, uric acid, and acid-base balance. Disturbances in hematologic function are not infrequent in alcoholic patients, including anemias from many causes, altered granulocyte responses, and thrombocytopenia.

Acid-Base Imbalance↗
PubMed1991

Gemfibrozil-induced myopathy.

Drug-induced myopathy has been reported with use of lovastatin, nicotinic acid, and clofibrate. A particularly severe form, often accompanied by rhabdomyolysis, has been reported with the use of lovastatin and gemfibrozil; however, as far as we know, no case has been documented with use of gemfibrozil alone. Herein, we report the first case (to our knowledge of gemfibrozil-induced myopathy, confirmed by drug rechallenge.

Clofibrate↗
PubMed1989

Septic and nonseptic olecranon bursitis. Utility of the surface temperature probe in the early differentiation of septic and nonseptic cases.

Forty-six consecutive cases of olecranon bursitis were prospectively analyzed during a 1-year period. Eleven cases were septic; 35 cases were nonseptic. In addition to bursal fluid analysis, the surface temperature over the involved olecranon bursa and the contralateral (control) olecranon process was obtained by using a surface temperature probe. We compared the temperature difference between the involved and control sides in all septic and nonseptic cases. In nonseptic cases, the mean surface temperature difference was 0.7 degree C vs 3.7 degrees C in septic cases. In all septic cases, the temperature difference was 2.2 degrees C or greater (range, 2.2 degrees C to 5.1 degrees C; SD, 1.1). Use of the surface probe temperature difference proved 100% sensitive and 94% specific in discriminating septic from nonseptic cases. It seems to be more helpful than the bursal fluid leukocyte count, the predominant cell type, or Gram's stain in the early differentiation of septic and nonseptic olecranon bursitis.

Adult↗
PubMed1989

Treatment of nonseptic olecranon bursitis. A controlled, blinded prospective trial.

We enrolled 42 patients with nonseptic olecranon bursitis in a double-blind prospective treatment trial to compare the efficacy of an intrabursal steroid preparation with that of an oral anti-inflammatory agent. Patients were randomized into one of four treatment regimens: (1) methylprednisolone acetate (20 mg) intrabursal injection and oral naproxen (1 g/d for 10 days), (2) methylprednisolone acetate (20 mg) intrabursal injection and oral placebo for 10 days, (3) oral naproxen (1 g/d for 10 days), and (4) oral placebo for 10 days. The degree of swelling in millimeters was assessed at study introduction and at 1, 3, and 6 weeks. At 6 months, the number of patients requiring reaspiration for bursitis recurrence was tabulated. Data at 1 week indicated that patients treated with an intrabursal methylprednisolone acetate injection (20 mg) demonstrated the most rapid decrease in swelling. At 6 weeks, the methylprednisolone-treated groups demonstrated sustained improvement. At 6 months, the mean number of reaspirations per patient for reaccumulation of bursal fluid was higher in groups 3 (1.0 +/- 1.2) and 4 (0.4 +/- 0.7). An intrabursal methylprednisolone acetate 20-mg injection seems to be the most effective treatment regimen for nonseptic olecranon bursitis.

Administration, Oral↗
PubMed1988

Physical examination: a revered skill under scrutiny.

Clinicians in the 1980s rely on the physical examination to a lesser degree than their predecessors in making diagnostic and therapeutic decisions. The major criticisms are that the physical examination lacks sensitivity for many common diseases and has not been subjected to the same scientific scrutiny afforded laboratory testing. On the positive side, the physical examination is a series of diagnostic maneuvers that permit physicians to test hypotheses generated during history taking, to determine disease severity, and to lessen clinical uncertainty. Furthermore, the physical examination fosters the development of personalized medical care and a bond of mutual trust between patient and doctor. The challenge for tomorrow is to determine the operating characteristics of physical examination techniques and the clinical utility of physical findings. For preclinical students, emphasis should be directed at basic examination principles and sequencing. Many model programs have used patient instructors and other innovative techniques. Clinical students and postgraduate trainees need emphasis on interpretation of physical findings and their integration into the clinical context. There is no substitute for bedside teaching at this level.

Curriculum↗
PubMed1987

Sjögren's syndrome. More than dry eyes and dry mouth.

Sjögren's syndrome is a complex disease state with multisystem manifestations. Two forms of the disease, primary and secondary, are recognized; the secondary form is more easily diagnosed because of its association with an already established rheumatic or autoimmune disease. Treatment consists of measures to prevent damage from ocular and oral dryness (sicca complex) and to minimize systemic manifestations.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1987

Gynecomastia. A worrisome problem for the patient.

Gynecomastia is common in obese or elderly men. Drug-induced breast enlargement is also frequent, whereas other causes of gynecomastia are relatively uncommon. Standardized measurement of breast tissue should be routinely performed in male patients. Diagnostic evaluation should be individualized on the basis of clinical suspicion. Therapy most often involves treating an underlying condition or discontinuing use of an offending drug.

Adult↗