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PubMed1997

Diagnosis and operation for anomalous circumflex coronary artery.

BACKGROUND: Origin of the left circumflex coronary artery from the right sinus of Valsalva is the most common anatomic variation of the coronary artery circulation. However, there are few reports about the operative approach to this anomalous vessel. METHODS: Forty patients having this anomaly were identified from 10,216 adult cardiac catheterization procedures. Forty percent of the anomalous circumflex coronary arteries (ACCAs) had critical atherosclerotic lesions. Eighty cases needed bypass grafting. RESULTS: For diagnosis of ACCA, the aortic root sign was positive in 94.9% of the diagnosed patients and the nonperfused myocardium sign was found in 92.5%. Eighty percent of ACCAs were larger than 2 mm in radiographic diameter before their passage into the atrioventricular groove. However, after emerging from the atrioventricular groove, 70% measured less than 1.5 mm. Consequently, a technique was developed to bypass the proximal ACCA and was used in 2 cases. Six other patients with more distal disease and larger vessels underwent conventional bypass grafting. CONCLUSIONS: The aortic root sign and nonperfused myocardium are useful in diagnosing ACCA. The ACCA is usually too small for use of the conventional graft technique. Therefore, a technique was developed to graft more proximally and was applied successfully in 2 cases.

Adult↗
PubMed2003

Analysis of the apo(a) size polymorphism in Asian Indian populations: association with Lp(a) concentration and coronary heart disease.

Most studies aiming to detect associations of genetic variation with common complex diseases, e.g. coronary heart disease (CHD) have been performed in populations with a western lifestyle but it is unclear whether associations detected in one geographic group exist also in others. We here have determined lipoprotein(a) levels and apo(a) K-IV-2 repeat genotypes in CHD patients (N=254) and controls (N=480) from two Asian Indian populations (Tamil Nadu and New Delhi). In both populations and also in the pooled dataset median Lp(a) levels were significantly elevated in the patients (27.4 mg/dl) compared with the controls (17.6 mg/dl). Apo(a) K-IV-2 allele frequencies were not different between the CHD patients and controls and thus did not explain the increased Lp(a) levels in CHD patients. Contrary to what has recently been observed in Black and White men short (K-IV or=30) apo(a) alleles were all associated with higher Lp(a) levels in the patients. Accordingly relative risk (estimated as odds ratio) for CHD rose continuously with increasing Lp(a) but was independent of apo(a) allele length. Together with previous studies our results indicate that the relation between apo(a) genotypes, Lp(a) levels, and CHD may be heterogeneous across ethnic groups and that it depends on the genetic architecture of the Lp(a) trait in a given population whether an association of K-IV-2 repeat length with CHD exists or not.

Adult↗
PubMed1978

Obturator prosthesis design for acquired maxillary defects.

Fabrication of obturator prostheses does not require a special ability to fabricate a prosthesis extension into a defect or an arbitrary extension of a prosthesis into a defect. Fabrication of an obturator prosthesis depends on the application of basic prosthodontic principles that are used in the treatment of patients without maxillary defects. Some principles must be modified because of the defect and the character and position of the remaining structures. The defect, in conjunction with the remaining structures, must be used to provide support, retention, and stability of an obturator prosthesis. If basic prosthodontic principles are applied the size and extension of the obturator will be determined, and the extensive variation so commonly seen in obturators will be minimized. Acceptable prosthodontic care for the patient with the acquired maxillary defect should include cautious prosthesis design combined with routine maintenance care to provide comfort, function, cosmetics, and minimal change to the compromised remaining structures.

Alveolar Process↗
PubMed1976

Hepatorenal artery bypass in the management of renovascular hypertension.

Infrequently, when the aorta cannot be used for a standard renal bypass operation because of a previous aortic operation, severe degenerative atherosclerosis or complete aortic thrombosis, a unilateral (hepatic) or bilateral (hepatic and splenic) visceral bypass should be contemplated. Patients with abdominal aortic aneurysms extending above the renal arteries might benefit from concomitant bilateral visceral bypass procedures followed by aortic replacement during the same operative session. The hepatic circulation with its common anatomic variations, indications, surgical technique and effects of hepatorenal artery bypass on the renal and hepatic circulation are discussed.

Female↗
PubMed2000

Hypothetical way of pollen aperture patterning. 2. Formation of polycolpate patterns and pseudoaperture geometry.

Deviant forms of polycolpate pollen, differing from the typical pattern in the number and arrangement of apertures, are found to be similar in distantly related dicotyledon taxa. The range of variation of common and deviant aperture patterns may be arranged as a continuous series, which may be described as a gradual and geometrically regular transformation of the deviant form with a meridional circular colpus to one of the common polycolpate conditions. Similar series have been observed in the taxa with colporate and pseudocolpate pollen. All possible spatial isomers and their mirror symmetrical variants of the deviant polycolpate and polypseudocolpate pollen have been predicted in terms of the suggested regularities of aperture multiplication. Some of them have been identified in the samples studied.

Journal Article↗
PubMed2001

Pancreas divisum: endoscopic therapy.

Pancreas divisum is a common congenital variation that can be associated with pancreatic disease. Symptomatic patients with divisum must be classified according to clinical presentation and morphologic findings. Response to endoscopic therapy is best in patients with ARP, of whom 75% benefit. Results in patients with chronic pancreatitis and pain but without objective pancreatitis are mixed, and patients should be carefully selected.

Congenital Abnormalities↗
PubMed2000

Salience from feature contrast: variations with texture density.

The salience of popout targets was measured in regular line arrays as a function of texture density. Test targets (singletons with orientation, motion, or luminance contrast) presented at different raster widths were compared with reference lines (lines brighter than surrounding lines) presented at fixed raster width. The luminance at which the reference target appeared as salient as the particular test target was taken as a measure of the relative salience of the test target. For orientation or motion contrast, targets at medium to small raster widths were far more salient than targets in sparse or very dense line arrangements. For targets defined by luminance contrast, salience variations with texture density were less pronounced. Some subjects also reported salience for lines in sparse arrangements even when these did not display feature contrast. When such non-specific saliency effects were subtracted from the actual measurements, salience curves for orientation or motion contrast revealed peaks of increased sensitivity at line spacings below 2-3 deg and flat curves at larger grid sizes. In an additional experiment, saliency effects from orientation contrast were measured using texture lines of different size. Salience variations were commonly observed. However, the curves were not found to scale with the different sizes of texture elements but were constantly related to the free space between neighbouring lines. This suggests that peaks in the salience profiles reflect the limited spatial extent of the underlying neural mechanisms.

Adolescent↗
PubMedDate not supplied

Midwifery management of pain in labor. The CNM Data Group, 1996.

Joint data collection by nine nurse-midwifery practices in the United States permitted a description of pain management practices with intrapartum patients. Observational data are reported for healthy gravidas at term (N = 4,171). A wide variety of techniques for pain management, including both pharmacologic and nonpharmacologic methods, were used. High prevalence modalities were paced breathing (used by 55.2% of this clinical sample), activity and position change (42.4%), narcotics (30.0%), and epidurals (18.7%). Paced breathing plus narcotics was the most common combination. Variations are reported for subgroups of women according to age, parity, race/ethnicity, education, insurance, marital status, activity in labor, and type of delivery. The only methods associated with a lowered rate of spontaneous delivery were epidurals and intrathecal narcotics.

Adult↗
PubMedDate not supplied

A proposed charter for clinical trial data monitoring committees: helping them to do their job well.

Formal monitoring of data from randomised controlled trials (RCTs) is becoming more common. Wide variation exists in the structure and organisation of data monitoring committees (DMCs), with little guidance on how they should operate. We used various strategies to consider the behavioural, procedural, and organisational aspects of data monitoring in RCTs: systematic reviews of DMCs and small group processes in decision making; surveys of reports of RCTs, recently completed and ongoing RCTs, and the policies of major organisations connected with RCTs; detailed case studies of four DMCs that faced difficult decisions; and interviews with experienced DMC members. The findings aided the development of a template for a charter for DMCs. We summarise the findings and outline the key considerations at every stage of the data monitoring process. Widespread use of a charter for the structure and organisation of DMCs would promote a systematic and transparent approach, and enable them to operate more effectively and efficiently.

Clinical Trials Data Monitoring Committees↗
PubMed2003

Not only vasopressin, but also the intracellular messenger protein kinase Calpha in the suprachiasmatic nucleus correlates with expression of circadian rhythmicity in voles.

The suprachiasmatic nucleus (SCN) is the locus of the main pacemaker for circadian behavioral rhythms. In common voles, variation in circadian behavioral rhythmicity correlates with vasopressin (AVP) immunoreactive cells in the SCN. Here we studied the immunostaining of four AVP linked Ca(2+)-dependent protein kinase C (PKC) isoforms (PKCalpha, PKCbeta1, PKCbeta2, and PKCgamma) at the beginning of the light period, and conclude that PKCalpha is highly expressed in the vole SCN compared to the other isozymes. Voles, characterized as strongly circadian rhythmic showed circadian variation in numbers of PKCalpha immunoreactive SCN neurons, while voles with weak or no circadian rhythmicity did not reveal such a circadian profile. PKCalpha immunoreactivity in acute SCN slices that were treated with a physiological dose of AVP was significantly lowered when compared with control slices. The intracellular messenger PKCalpha may reflect variation in locomotor behavior via the AVP system in the vole SCN. This system could play a key role in the vole SCN by mediating output of its circadian clock.

Animals↗
PubMed2000

Diurnal blood pressure variations in incipient and end stage diabetic renal disease.

Our aim was to compare the diurnal blood pressure patterns of people with Type 1 diabetes on continuous ambulatory peritoneal dialysis (CAPD, n=9) or haemodialysis (n=10) to diabetic patients with normo-albuminuria (n=12) or micro-albuminuria (n=15). Blood pressure was measured with an ABPM02 Meditech oscillometric blood pressure monitor. The micro-albuminuric group had significantly higher nocturnal diastolic and mean arterial pressures than the normo-albuminuric group. CAPD and haemodialysis patients had significantly higher day time, nocturnal mean systolic, diastolic and mean arterial blood pressures. Micro-albuminuric and end-stage renal failure patients displayed a loss of the physiological drop of systolic blood pressure, which was only significant in the normo-albuminuric group. Nocturnal drop of blood pressure characterised by diurnal indices were 7.4% in the CAPD, 8.8% in the haemodialysis, 10.0% in the micro-albuminuric and 16.5% in the normo-albuminuric group. These results suggest, that pathological circadian blood pressure variation is common in diabetic patients on dialysis, and ambulatory blood pressure monitoring can be a useful tool both in its the detection and its adequate treatment.

Adult↗
PubMed2002

Pathogen occurrence and antimicrobial resistance trends among urinary tract infection isolates in the Asia-Western Pacific Region: report from the SENTRY Antimicrobial Surveillance Program, 1998-1999.

Worldwide surveillance of antimicrobial resistance among urinary tract pathogens is useful to determine important trends and geographical variation for common Gram-positive and -negative species. The most common causative uropathogens often have intrinsic or acquired resistance mechanisms which include ESBL production among enteric bacilli, multi-drug resistant staphylococci and non-fermentative Gram-negative bacilli such as Pseudomonas aeruginosa and Acinetobacter spp. and vancomycin-resistant Enterococcus spp. This study evaluates pathogen frequency and the resistance rates among urinary tract infection (UTI) pathogens in 14 medical centres in the Asia-Pacific region between 1998 and 1999. The isolates were referred to a central monitor for reference NCCLS broth microdilution testing, identification confirmation and patient demographic analysis. Over 50% of the 958 pathogens were Escherichia coli and Klebsiella spp. followed by P. aeruginosa, Enterococcus spp. and Enterobacter spp. Susceptibility for the three enteric bacilli was high for carbapenems (100%), 'fourth-generation' cephalosporins (cefepime 94.9-98.6%) and amikacin (> or = 93.0%). Beta-lactamase inhibitor compounds were more active against E. coli (piperacillin/tazobactam; > 90% susceptible) than the other two enteric species and all other tested agents had a narrower spectra of activity. The rank order of anti-pseudomonal agents was amikacin (91.5% susceptible)> imipenem > piperacillin/tazobactam > tobramycin > ceftazidime and cefepime (77.4 and 76.4% susceptible, respectively). Susceptibility to quinolones for the P. aeruginosa isolates was only 63.2-67.0%. Only one vancomycin-intermediate Enterococcus spp. (van C phenotype) was detected among the 103 strains tested. Newer fluoroquinolones (gatifloxacin; MIC(50), mg/l) were more potent against enterococci than ciprofloxacin (MIC(50), 2 mg/l) and high-level resistance to aminoglycosides was common (41.7%). The data presented are compared to studies of similar design from other areas which are part of the SENTRY surveillance network.

Anti-Bacterial Agents↗
PubMed2002

Using control charts to assess performance measurement data.

BACKGROUND: In 1997 the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) announced the ORYX initiative, which integrates outcomes and other performance measurement data into the accreditation process. JCAHO uses control and comparison charts to identify performance trends and patterns that are provided to JCAHO surveyors in advance of the organization's survey. During its survey, the health care organization (HCO) is asked to explain its rationale for its selection of performance measures, how the ORYX data have been analyzed and used to improve performance, and the outcomes of these activities. WHAT DO CONTROL CHARTS DO? Control charts indicate whether an HCO's process is in statistical control (that is, stable insofar as only common cause variation exists) or out of statistical control (that is, unstable insofar as special cause variation exists). With the presence of special cause variation, the HCO should not make any change in its processes until the special cause is identified and eliminated. CHOOSING THE CORRECT CONTROL CHART: An HCO can use many different control charts. Selecting the correct control chart type for the type of data collected makes interpretation more sensitive for detecting special cause variation. The ORYX measures are calculated as proportions (rates), ratios, and means (continuous variables data, such as average length of stay), and this information forms the basis for selecting the correct type of control chart. In addition, the average rate (especially for rare event measures) and the average number of cases need to be considered when selecting the control chart type for small population measures.

Accidental Falls↗
PubMed2003

Simultaneous determination of levomepromazine, midazolam and their major metabolites in human plasma by reversed-phase liquid chromatography.

A sensitive and reliable high-performance liquid chromatographic (HPLC) assay is a prerequisite for pharmacokinetic analysis of continuous infusion of levomepromazine adjuvant to midazolam. We developed such a method to determine the levels of levomepromazine, midazolam and their major metabolites (levomepromazinesulfoxide, desmethyl-, didesmethyllevomepromazine, O-desmethyllevomepromazine and alpha-hydroxy-midazolam) simultaneously. Desmethylclomipramine was used as an internal standard (I.S.). The lower limit of quantification of this assay was set for levomepromazine 4.1 microg/l, levomepromazinesulfoxide 4.9 microg/l, O-desmethyllevomepromazine 18.4 microg/l, alpha-hydroxymidazolam 26.6 microg/l, midazolam 23.4 microg/l, didesmethyllevomepromazine 15.8 microg/l, and desmethyllevomepromazine 6.6 microg/l. The between- and within day assay variations were commonly below 5%. The recovery in human plasma for the different analytes varied between 85 and 11%. The accuracy of this assay varied between 95 and 105% for the different concentrations. The linearity of this assay was set between 25 and 800 microg/l (r(2)>0.999 of the regression line). The first results of pharmacokinetic analysis of midazolam indicated that half-life varied between 1.1 and 1.9 h. Pharmacokinetic analysis using a one-compartment model of levomepromazine revealed that the apparent volume of distribution was 4.1+/-2.4 l per kg lean body mass and the metabolic clearance was 309+/-225 l per hour per 70 kg. This assay proved to be robust and reproducible. It can reliably be used for further study of the pharmacokinetics of continuous infusion of levomepromazine.

Analgesics, Non-Narcotic↗
PubMed2002

Lack of association between the SOST gene and bone mineral density in perimenopausal women: analysis of five polymorphisms.

Osteoporosis is a common disease characterized by a decrease in bone mass, architectural deterioration of the bone tissue, and an increased risk of fracture. The condition is under strong genetic control, involving a large variety of gene products, but to date the genes responsible remain poorly defined. Although population-based studies have identified polymorphisms in several candidate genes that are associated with bone mineral density (BMD), these account for only a small proportion of the population variance in bone mass. In this study, we looked for evidence of an allelic association between polymorphisms in the SOST gene and BMD. This gene was analyzed because loss-of-function mutations in SOST cause sclerosteosis, a sclerosing bone dysplasia associated with increased bone mass due to increased bone formation. We identified 26 different polymorphisms in the SOST gene and selected 5 of these for association analysis in a case-control study of 619 women with either high or low BMD, drawn from a random population-based survey of 5119 perimenopausal white women. The high BMD group comprised 326 women in whom lumbar spine BMD values adjusted for age, height, and weight were in the highest 16% of the population distribution, and the low BMD group comprised 293 women in whom BMD values were in the lowest 16% of the population distribution. The distribution of genotypes and alleles for each Single Nucleotide Polymorphism (SNP) examined did not differ in the low and high BMD groups. We conclude that, in this population, common allelic variations in the SOST gene do not contribute significantly to the regulation of high or low BMD.

Adaptor Proteins, Signal Transducing↗
PubMed1980

The epidemiological type identification of Serratia marcescens from outbreaks of infection in hospitals.

A study of serological, bacteriocine and phage typing of Serratia marcescens was made. Specific O-antisera of adequate titre were relatively simple to prepare but H-antisera exhibited many heterologous agglutination reactions amongst the type strains. Most of these cross-reactions were not reproduced when immobilization tests with H-sera were performed. Direct haemagglutination tests were used to establish the presence of fimbriae amongst the H-type strains and the results of agglutination tests with non-fimbriate variants of strains indicated that fimbrial antibody in high titre was present in some sera. Replicate typing of 100 pairs of cultures by the phage-typing method indicated that small variations in pattern were common and that larger variations occurred occasionally. Therefore differences in pattern of less than two strong reactions should not be taken as evidence that strains can be distinguished. Cultures of S. marcescens, 273 in total, from six outbreaks of infection in British and European hospitals were typed by O-serology, H agglutination and immobilization tests, phage typing and bacteriocine susceptibility by a cross-streaking method. The typability of strains by each method was high but the results suggested that no single method was sufficiently discriminating to be used alone for typing. Comparison of the H-type and typing patterns of members of the same O serogroup from incidents of infection showed that reliable results were obtained by H-typing or by phage and bacteriocine typing after the application of the appropriate 'difference' rule. The greatest discrimination between strains of the same O-group was obtained by the use of H-typing or phage typing.

Aged↗
PubMed1977

A comparison of typing methods for Serratia marcescens.

A simple method for the bacteriocine typing of Serratia marcescens without the use of induction was sought. The results of a mutual inhibition experiment with 89 unrelated cultures indicated that a bacteriocine-susceptibility method would give more discrimination between strains than would a bacteriocine-production method. A cross-streaking technique for bacteriocine-susceptibility typing without previous induction was developed, and its performance was compared with that of another susceptibility-typing method in which cell-free lysates of the producer strains were obtained by induction with mitomycin C.Replicate typing of the same collection of cultures by both methods indicated that small variations in pattern were common and that larger variations occurred occasionally. Differences in pattern of less than two strong reactions in the mitomycin-C induction method, and of less than three strong reactions in the cross-streaking method, should therefore not be taken as evidence that strains can be distinguished.Sets of cultures of Ser. marcescens, 178 in total, from a number of supposed incidents of infection in hospitals, were used to evaluate the two bacteriocine-typing methods; all of the cultures were also O serogrouped. Comparison of the typing patterns of members of the same O serogroup from clear-cut incidents of infection confirmed that results of acceptable reliability could be obtained by either bacteriocine-typing method by the application of the appropriate ;difference' rule. When so interpreted, the cross-streaking method appeared to be slightly the more discriminatory.The greatest discrimination between strains was obtained by the use of a ;hierarchical' typing system in which the strains were first O serogrouped, and the cross-streaking method of bacteriocine typing was then used to make subdivisions within O serogroups.

Bacteriocins↗