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C Young

Publications and source records attributed to C Young.

At least 109 records · Page 6Linked to original sources
PubMed1998

quemao, a Drosophila bristle locus, encodes geranylgeranyl pyrophosphate synthase.

The quemao (qm) locus of Drosophila melanogaster is characterized by a P-element-associated mutant lacking most of the large bristles on the thorax and by several EMS-induced recessive lethals. quemao was cloned using a transposon tagging strategy. P-element-mediated transformation demonstrated that the cloned qm DNA sequence (from the 65F cytological region) rescues the mutant phenotype. A 2.3-kb qm transcript was identified by Northern blot analysis by sequencing of the isolated qm cDNA clones and by 5' rapid amplification cDNA end (RACE). The predicted amino acid sequence (338 residues) of the coding region of the qm transcript shares 42, 31, 13, 20, and 12% identical amino acid sequences with the geranylgeranyl pyrophosphate synthase (GGPPS) of fungi, yeast, plants, archaebacteria, and eubacteria, respectively. It also contains five highly conserved domains common among all known isoprenyl pyrophosphate synthases. The P element associated with the original qm mutant is inserted in the 5' untranslated region of the transcript. An EMS-induced qm nonsense mutation at the 12th codon leads to recessive lethality at the first larval instar, indicating the essential role of qm in the isoprenoid biosynthesis of insects.

Amino Acid Sequence↗
PubMed1998

Improving efficiencies and reducing costs in adult cardiac surgery: a team approach.

The article reviews a team effort to reduce operating room costs by 25 percent. The team achieved this goal by participating in the Institute for Healthcare Improvement Breakthrough Series on adult cardiac surgery. The process improvements included standardizing practices, reevaluating equipment, and reducing operating room cycle time.

Adult↗
PubMed1998

Routine cholecystocholangiography: a viable alternative during laparoscopic cholecystectomy.

BACKGROUND: The advantages of cholangiography during laparoscopic cholecystectomy (LC), including identification of biliary anatomy and biliary calculi, are well known. The usefulness of cholecystocholangiography (CCC), by direct injection through the gall-bladder, compared to the more popular cystic duct cholangiography (CDC), however, is not so well known. METHODS: Two hundred consecutive patients who underwent LC were included in a prospective study of routine CCC. Between 5 and 60 mL of contrast is injected through the gall-bladder fundus, using image intensifier control. RESULTS: Cholecystocholangiography was attempted in 194 cases and was successful in 157 (80.9%). Twenty-one of the 37 cases with a failed CCC proceeded to have a successful CDC, giving an overall cholangiography success rate of 91.8%. The presence of acute inflammation decreased the success rate. Eleven (6%) true positive cases of common bile duct (CBD) calculi were demonstrated (nine on CCC and two on CDC after failed CCC). There was one case of false positive CBD calculus and no false negatives. CONCLUSIONS: We have found that the routine use of CCC during LC is safe, successful, quick to perform, and does not prevent conversion to attempted CDC in the cases where it fails. Cholecystocholangiography may have advantages over CDC and be an alternative as the preferred imaging technique.

Cholangiography↗
PubMed1998

Cerebral hemodynamic response to generalized spike-wave discharges.

PURPOSE: Data in the literature concerning metabolic demand during generalized spike-wave activity (gSW) are conflicting. We investigated instantaneous changes in cerebral blood flow velocities (CBFV) in both middle cerebral arteries (MCAs) by transcranial Doppler sonography (TCD) during gSW paroxysms recorded by scalp EEG. METHODS: In 13 patients, CBFVs in both MCAs were averaged, time-locked to the occurrence of the gSW; respiratory rate (RR) and end-expiratory pco2 were measured in one patient. RESULTS: Nine patients showed significant changes in CBFV during gSW. Four had biphasic flow changes with an initial increase (p < 0.05) and a subsequent decrease (p < 0.01). This was partially paralleled by an increase in RR (p < 0.01) and a decrease in pco2 (p < 0.01). In three patients, an increase in CBFV that preceded the onset of gSW by several seconds was observed, followed by a decrease in CBFV. Two patients showed a significant decrease only of CBFV. Only gSWs of a median duration of >0.8 s were associated with significant changes in CBFV. CONCLUSIONS: We were able to demonstrate that gSWs of several seconds duration lead to cortical perfusion changes. We suggest that the initial increase of CBFV demonstrated in some patients reflects neuronal activation, whereas the subsequent decrease might in part be due to hyperventilation-induced hypocapnia.

Adult↗
PubMed1998

Multiple atrioventricular nodal pathways in humans: electrophysiologic demonstration and characterization.

INTRODUCTION: Multiple AV nodal pathway physiology can be demonstrated in certain patients with clinical AV reentrant tachycardia. METHODS AND RESULTS: Evidence suggesting multiple AV nodal pathway conduction was present in seven (two males; age range 15 to 75 years) of 78 patients (9%) who underwent electrophysiologic studies for AV nodal tachycardia. The presence of two discrete discontinuities in the AV nodal conduction curves suggested triple AV nodal pathway conduction. Detailed mapping of their retrograde atrial activation sequence was performed along the tricuspid annulus from the coronary sinus ostium to the His-bundle electrogram recording site. Three zones (anterior, middle, and posterior) correspond to the upper, middle, and lower third of the triangle of Koch, respectively. The fast pathway exits were determined as anterior (4/7) or middle (3/7), the intermediate pathway exits as middle (4/7) or posterior (3/7), and the slow pathway exits as middle (1/7) or posterior (6/7). Other evidence suggesting multiple AV nodal pathway conduction includes: (1) triple ventricular depolarizations from a single atrial impulse; (2) sequential dual ventricular echoes; (3) spontaneous transformation between the slow-fast and fast-slow forms of AV nodal reentrant tachycardia; and (4) persistent cycle length alternans during AV nodal reentrant tachycardia. In four patients, all three pathways were shown to be involved in AV nodal echoes or reentrant tachycardia. CONCLUSION: Multiple AV nodal pathways are not uncommon and can be identified by careful electrophysiologic elucidation and mapping technique.

Adolescent↗
PubMed1998

Use of the BacT/Alert blood culture system for culture of sterile body fluids other than blood.

Studies have demonstrated that large-volume culture methods for sterile body fluids other than blood increase recovery compared to traditional plated-medium methods. BacT/Alert is a fully automated blood culture system for detecting bacteremia and fungemia. In this study, we compared culture in BacT/Alert standard aerobic and anaerobic bottles, BacT/Alert FAN aerobic and FAN anaerobic bottles, and culture on routine media for six specimen types, i.e., continuous ambulatory peritoneal dialysate (CAPD), peritoneal, amniotic, pericardial, synovial, and pleural fluids. Specimen volumes were divided equally among the three arms of the study. A total of 1,157 specimens were tested, with 227 significant isolates recovered from 193 specimens. Recovery by method was as follows: standard bottles, 186 of 227 (82%); FAN bottles, 217 of 227 (96%); and routine culture, 184 of 227 (81%). The FAN bottles recovered significantly more gram-positive cocci (P < 0.001), Staphylococcus aureus (P = 0.003), coagulase-negative staphylococci (P = 0.008), gram-negative bacilli (P < 0.001), Enterobacteriaceae (P = 0.005), and total organisms (P < 0.001) than the routine culture. There were no significant differences in recovery between the standard bottles and the routine culture. The FAN aerobic bottle recovered significantly more gram-positive cocci (P < 0.001), S. aureus isolates (P < 0.001), coagulase-negative staphyococci (P = 0.003), and total organisms (P < 0.001) than the standard aerobic bottle, while the FAN anaerobic bottle recovered significantly more gram-positive cocci (P < 0.001), S. aureus isolates (P < 0.001), Enterobacteriaceae (P = 0.03), and total organisms (P < 0.001) than the standard anaerobic bottle. For specific specimen types, significantly more isolates were recovered from the FAN bottles compared to the routine culture for synovial (P < 0.001) and CAPD (P = 0.004) fluids. Overall, the FAN bottles were superior in performance to both the standard bottles and the routine culture for detection of microorganisms from the types of sterile body fluids included in this study.

Bacteria↗
PubMed1998

Multicenter evaluation of the COBAS AMPLICOR HCV assay, an integrated PCR system for rapid detection of hepatitis C virus RNA in the diagnostic laboratory.

The benefits shown by the recent introduction of PCR for the in vitro diagnosis of hepatitis C virus (HCV) infection has prompted the development of standardized, ready-to-use assays that can be implemented in routine clinical laboratories. We have evaluated the clinical performance of COBAS AMPLICOR HCV (COBAS), the first instrument system that allows the automation of HCV RNA amplification and detection, to determine its performance in the routine laboratory setting. More than 2,000 specimens collected at five centers were analyzed in parallel by the COBAS and the manual AMPLICOR HCV (AMPLICOR) tests, and the results were compared with the results for biochemical and serological markers of HCV. In this study the two PCR systems showed the same accuracy, with a concordance rate of 99.8%. As expected, the correlation between serology and PCR was not absolute because the presence of anti-HCV antibodies may be associated with a latent or past infection. On the other hand, if the presence of confirmed anti-HCV antibodies and elevated alanine aminotransferase levels are taken as the "gold standard," indicating an active, ongoing infection, the COBAS and AMPLICOR tests show high and comparable sensitivities (100%) and specificities (98%), with positive and negative predictive values of 100 and 97%, respectively. During the study no false-positive reactions were detected. The use of an internal control allowed the identification of inhibitory substances that prevented amplification for 0.3 and 0.4% of samples tested by the COBAS and AMPLICOR tests, respectively. Compared to the manual system, the COBAS system allowed a significant reduction of hands-on time and could improve the overall laboratory work flow. In conclusion, these results support the use of the COBAS and AMPLICOR tests for the molecular diagnosis of active HCV infections.

Hepacivirus↗
PubMed1998

Fibroelastoma: case report and review of the literature.

A 64 year old woman presented with right hemianaesthesia and was found to have a pansystolic apical murmur with systolic and diastolic posture related plops. Echocardiography revealed a mobile mass on the mitral valve apparatus that was confirmed by magnetic resonance imaging. This was successfully excised and was proven on histopathological examination to be a fibroelastoma. Other cases of fibroelastoma from the literature are reviewed.

Echocardiography↗
PubMed1998

Quality of life in multiple sclerosis in France, Germany, and the United Kingdom. Cost of Multiple Sclerosis Study Group.

OBJECTIVE: To assess the quality of life (QoL) of patients with multiple sclerosis in France, Germany, and the United Kingdom with a cross sectional study. METHODS: Patients were classified into three severity groups according to the expanded disability severity scale (EDSS); stage I, II, and III, corresponding to mild (EDSS 1.0-3.5), moderate (EDSS 4.0-6.0), or severe (EDSS 6.5-8.0) multiple sclerosis respectively. Ninety patients with multiple sclerosis and 30 control patients without multiple sclerosis were recruited in each country. Control patients were matched to the patients with multiple sclerosis according to age and sex. Quality of life was assessed using the functional status questionnaire (FSQ). RESULTS: The aspects of QoL that were mostly affected in the three countries under study were physical function and general wellbeing. Social role function decreased with increased severity of disease in France and in particular in Germany. Multiple sclerosis did not seem to have an impact on psychological function. The QoL of control patients was systematically higher than that of patients with multiple sclerosis. CONCLUSIONS: Use of such a generic scale showed that progression of multiple sclerosis is accompanied by a decrease in QoL and suggested that this could be a relevant measurement in assessing the effect of treatment and progression of disease. Variation between countries, however, may be important.

Adult↗
PubMed1998

Economic evaluation of multiple sclerosis in the UK, Germany and France.

A cross-sectional cost-of-care study was performed to assess the economic burden of multiple sclerosis (MS) in France, Germany and the UK. Patients were stratified into 3 groups according to the Expanded Disability Severity Scale (EDSS): stages I, II and III, corresponding to mild (EDSS 1.0 to 3.5), moderate (EDSS 4.0 to 6.0) and severe (EDSS 6.5 to 8.0) MS, respectively. 90 patients with MS and 30 non-MS control patients were recruited in each country. Control patients were matched to the patients with MS on the basis of age and gender. Demographic, clinical and economic data during the 3-month period prior to entry were collected in patient interviews. Total costs included actual expenditures, such as direct medical and non-medical costs, as well as indirect costs. From the societal perspective, the total cost of MS for 3 months was estimated at 1,928 US dollars, 3,941 US dollars and 5,678 US dollars in France, 2,772 US dollars, 2,056 dollars and 5701dollars in Germany, and 5,125 US dollars, 6,751 US dollars and 14, 622 US dollars in the UK, for stage I, II and III patients, respectively. The major medical cost driver in the UK was outpatient consultations, whereas hospitalisations were the major component in Germany and France. The major cost in the UK arose from the dependence of patients with MS on caregivers, which caused high non-medical, societal costs compared with France and Germany. From both the societal and health insurance perspectives in each country, costs for control patients were lower than those for stage I MS patients. MS represents a major financial burden on the individual, the family, health services and society, and these costs increase with MS progression.

Adult↗
PubMed1998

Comparison of various antibiotic treatments for cows diagnosed with toxic puerperal metritis.

Holstein cows (n = 51) that had been diagnosed with toxic puerperal metritis were used to determine the treatment efficacy of various antibiotics. On the day of diagnosis, cows affected with toxic puerperal metritis were assigned randomly to three treatment groups. Cows in groups 1 and 2 received 22,000 IU/kg of procaine penicillin G i.m. for 5 d. In addition, cows in group 2 received an intrauterine infusion of 6 g of oxytetracycline on d 1, 3, and 5. Cows in group 3 received 2.2 mg/kg of ceftiofur sodium i.m. for 5 d. Dependent variables used to determine antibiotic efficacy included milk yield on d 1 through 12, rectal temperature on d 1 through 5, and serum haptoglobin concentration on d 1, 3, and 5. No difference was observed among groups for milk yield on d 1 and 12 or for temperature on d 1 and 5. Serum haptoglobin was elevated to > 10 mg/dl for cows in all groups; however, no difference was observed among groups on d 1 and 5. Because all groups showed a favorable response, this study suggests that there is no difference in treatment efficacy among antibiotics used to treat cows affected with toxic puerperal metritis.

Animals↗
PubMed1998

Utrophin mRNA Expression in Muscle Is Not Restricted to the Neuromuscular Junction.

Utrophin is normally present exclusively in synaptic regions of skeletal muscle fibers, although it is expressed extrasynaptically in certain pathological situations, where it has been proposed to compensate for the absence of dystrophin in Duchenne muscular dystrophy patients and mdx mice. Recently there have been conflicting reports regarding the preferential expression of utrophin mRNA at the neuromuscular junction. Using in situ hybridization with RNA probes, we show a clear accumulation of autoradiographic labeling at more than 90% of neuromuscular junctions (identified by histochemical demonstration of cholinesterase activity). The intensity of this labeling is proportional to the number of junctional myonuclei in the section. Some clusters of labeling were found associated with nonmuscle nuclei (e.g., blood vessels, nerves), where utrophin is present. In addition, labeling for utrophin mRNA was associated with about 25% of extrajunctional myonuclei, where the protein is not present. The mean labeling per nucleus at junctional myonuclei was at least 10 times greater than at extrajunctional myonuclei. We discuss the possible regulatory mechanisms involved in the heterogeneous expression of utrophin mRNA in skeletal muscle. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

Patient noncompliance with hormone replacement therapy: a nationwide estimate using a large prescription claims database.

OBJECTIVE: The purpose of this investigation was to use a large prescription claims database to characterize noncompliance with hormone replacement therapy (HRT). DESIGN: A retrospective longitudinal analysis was conducted among 28,718 women aged 40-59 years who were new HRT users. In the present study, HRT was defined as an oral estrogen (with or without progestin in separate prescribing) or as an oral estrogen combination with 21 or more recommended therapy days for every 28 calendar days. Compliance was determined by constructing a ratio of the total days of HRT received during the follow-up period divided by the total number of days in the follow-up period (365 days). An individual with a medication availability ratio less than 0.75 was considered to be noncompliant. RESULTS: After 1 year, 54.4% of the study subjects were noncompliant with HRT. Noncompliance was associated with younger age, living in the southern region of the United States, and not having an obstetrician/gynecologist as the initial prescriber. CONCLUSIONS: Noncompliance with HRT in the general population is higher than that reported in randomized clinical trials, suggesting that women are not benefiting optimally from therapy and that they are at risk for unnecessary morbidity and mortality from osteoporosis and cardiovascular disease. Increased efforts to improve long-term HRT compliance are urgently needed.

Adult↗
PubMed1997

Postsynaptic abnormalities at the neuromuscular junctions of utrophin-deficient mice.

Utrophin is a dystrophin-related cytoskeletal protein expressed in many tissues. It is thought to link F-actin in the internal cytoskeleton to a transmembrane protein complex similar to the dystrophin protein complex (DPC). At the adult neuromuscular junction (NMJ), utrophin is precisely colocalized with acetylcholine receptors (AChRs) and recent studies have suggested a role for utrophin in AChR cluster formation or maintenance during NMJ differentiation. We have disrupted utrophin expression by gene targeting in the mouse. Such mice have no utrophin detectable by Western blotting or immunocytochemistry. Utrophin-deficient mice are healthy and show no signs of weakness. However, their NMJs have reduced numbers of AChRs (alpha-bungarotoxin [alpha-BgTx] binding reduced to approximately 60% normal) and decreased postsynaptic folding, though only minimal electrophysiological changes. Utrophin is thus not essential for AChR clustering at the NMJ but may act as a component of the postsynaptic cytoskeleton, contributing to the development or maintenance of the postsynaptic folds. Defects of utrophin could underlie some forms of congenital myasthenic syndrome in which a reduction of postsynaptic folds is observed.

Animals↗
PubMed1997

The timing and sequence of multiple device-related complications in patients with indwelling subcutaneous ports.

BACKGROUND: Multiple complications associated with venous access ports are a common occurrence. In an effort to define patterns of sequential complications in our community, we undertook a prospective analysis of adult cancer patients in whom a subcutaneous port was inserted. METHODS: One hundred nineteen consecutive adult cancer patients in whom a subcutaneous port was inserted were observed prospectively for the development of complications. RESULTS: Complications were identified in 70 of the 91 evaluable patients, while sequential complications were identified in 35 patients (38%). In aggregate, 121 complications were identified. The ball-valve effect, the most frequently identified problem, was found to occur disproportionately as a primary complication (52 of 70 versus 26 of 51, P <0.02). In contrast, port-related venous thrombosis was identified most frequently as a subsequent complication (11 of 51 versus 4 of 70, P <0.02). The only identified risk factor for the development of port-related complications was the ball-valve effect, found to be associated with the subsequent development of port-related venous thrombosis (9 of 52 versus 2 of 69, P <0.02). CONCLUSIONS: Multiple sequential complications of subcutaneous ports are common and occur in a rather predictable order. The occurrence of port-related venous thrombosis in patients with an earlier, relatively minor vascular complication (ball-valve effect) suggests a cause-effect relationship. Insight into complication sequencing may lead to improved strategies for prevention and therapy.

Adult↗
PubMed1997

Ischemia-induced anxiety following cardiac arrest in the rat.

Male Long-Evans rats were subjected to 7 min of chest compression (CC) to produce cardiac arrest and global ischemia resulting in damage to the brain. Timidity and motor activity were evaluated using the elevated plus maze, one of the most widely accepted methods for measuring anxiety in rats. Post-ischemic rats spent much less time in the open arms (3% at day 5) than handled (54%) or sham-compressed (30%) rats. This was interpreted as increased anxiety. Thus, post-ischemic rats developed more anxiety than normal handled rats or sham-operated rats. Anxiety increased markedly on post-ischemic day 2, suggesting a delayed effect. Anxiety gradually decreased after day 5 but recovery was still incomplete up to 115 days post-ischemia. Motor activity decreased gradually during days 2-5 post-ischemia and then recovered to the normal range after day 15. These results are inconsistent with damage limited to the hippocampus and suggest that less obvious histological changes may be occurring elsewhere in the brain.

Animals↗
PubMed1997

Access to emergency care under TennCare: do patients understand the system?

STUDY OBJECTIVE: To determine patient understanding of how to properly gain access to urgent and emergency medical care under TennCare, a government-mandated managed health care initiative designed to replace Medicaid in Tennessee. METHODS: We prospectively surveyed a convenience sample of ED patients at university hospital ED with an annual census of 50,000 during two periods (summer 1994 and summer 1995). In 1994, 250 TennCare patients were enrolled (part 1). In 1995, 199 were enrolled (part 2). RESULTS: Patients from seven different TennCare managed care organizations (MCOs) were interviewed. Thirty-eight percent of part 1 patients and 37% of part 2 patients did not have or did not know the names of their primary care physicians (PCPs). Fifty-eight percent of the part 1 patients who knew their PCPs' names had never visited them. This figure had decreased to 25% by the time part 2 patients were surveyed. Seventy-three percent of part 1 patients interviewed did not call their PCPs before coming to the ED. This figure had decreased to 48% by the time part 2 patients were interviewed. Thirty-two percent of part 1 patients were aware that they were supposed to contact the PCP before visiting the ED, whereas 94% of part 2 patients were aware of this requirement. Thirty-one percent of part 1 patients and 40% of part 2 patients who tried to contact their PCPs were unsuccessful, most often because of a delay on the part of PCPs in returning calls. Fifty-six percent of part 1 patients and 69% of part 2 patients did not know that they might be held responsible for the bill if an ED visit was not considered a true emergency and was not approved by the MCO. CONCLUSION: Improvements in communication of pertinent information must be implemented in managed care systems such as TennCare to better inform participants of the proper use of the system. MCOs will not reduce inappropriate use of the ED if patients are not aware of their responsibilities and do not know their PCPs or how to gain access to them. PCP responsiveness to patients must also be improved.

Adult↗