The effect of oral anticoagulant therapy on aptt results from a bedside coagulation monitor

Objective. The Ciba Corning 512 coagulation monitor (CC512) can be used to monitor heparin therapy by performing an activated partial thromboplastin time (APTT) at the patient’s bedside. This study was designed to compare the CC512 results to results using the laboratory system. The relative sensitivities of both systems to the effect of oral anticoagulant therapy also was investigated.Methods. Activated partial thromboplastin times were performed with both the CC512 and laboratory system on 74 specimens from patients receiving IV heparin therapy, and on 14 specimens from patients on warfarin only. Heparin assays were performed on 43 of the specimens from the heparinized patients.Results. When a patient was receiving heparin only, the APTT results of the CC512 proved to be similar to existing laboratory methods. The CC512 APTT results of patients on warfarin only were markedly prolonged, whereas the laboratory APTTs were only slightly affected.Conclusion. The CC512 results were comparable to the laboratory system. However, the CC512 APTT was more sensitive to the effect of warfarin than the laboratory APTT system used in this study. CC512 APTT results on a patient receiving both oral and intravenous anticoagulation could be misleading. The authors wish to thank D.M. O’Brien and the nursing staff of the Coronary Care Unit for providing CC512 data and laboratory specimens, and I. Smith for the preparation of graphics. We also wish to thank Australian Diagnostics Corporation, which provided consumables.     

National trends in Staphylococcus aureus infection rates: impact on economic burden and mortality over a 6-year period (1998-2003).

BACKGROUND: We evaluated historical trends in the Staphylococcus aureus infection rate, economic burden, and mortality in US hospitals from 1998 through 2003. METHODS: The Nationwide Inpatient Sample was used to assess trends over time of S. aureus infection during 1998-2003. Historical trends were determined for 5 strata of hospital stays, including all inpatient stays, surgical procedure stays, invasive cardiovascular surgical stays, invasive orthopedic surgical stays, and invasive neurosurgical stays. RESULTS: During the 6-year study period from 1998 through 2003, the rate of S. aureus infection increased significantly for all inpatient stays (from 0.74% to 1.0%; annual percentage change (APC), 7.1%; P=.004), surgical stays (from 0.90% to 1.3%; APC, 7.9%; P=.001), and invasive orthopedic surgical stays (from 1.2% to 1.8%; APC, 9.3%; P<.001). For invasive neurosurgical stays, the rate of S. aureus infection did not change from 1998 to 2000 but increased at an annual rate of 11.0% from 2000 to 2003 (from 1.4% to 1.8%; P=.034). The total economic burden of S. aureus infection for hospitals also increased significantly for all stay types, with the annual percentage increase ranging from 9.2% to 17.9% (P<.05 for all). In 2003, the total economic burden of S. aureus infection was estimated to be $14.5 billion for all inpatient stays and $12.3 billion for surgical patient stays. However, there were significant decreases in the risk of S. aureus-related in-hospital mortality from 1998 to 2003 for all inpatient stays (from 7.1% to 5.6%; APC, -4.6%; P=.001) and for surgical stays (from 7.1% to 5.5%; APC, -4.6%; P=.002). CONCLUSIONS: The inpatient S. aureus infection rate and economic burden of S. aureus infections for US hospitals increased substantially from 1998 to 2003, whereas the in-hospital mortality rate decreased.     

Overrepresentation of genetic variation in the AnkyrinG interactome is related to a range of neurodevelopmental disorders

Upon the discovery of numerous genes involved in the pathogenesis of neurodevelopmental disorders, several studies showed that a significant proportion of these genes converge on common pathways and protein networks. Here, we used a reversed approach, by screening the AnkyrinG protein-protein interaction network for genetic variation in a large cohort of 1009 cases with neurodevelopmental disorders. We identified a significant enrichment of de novo potentially disease-causing variants in this network, confirming that this protein network plays an important role in the emergence of several neurodevelopmental disorders.Subject terms: Genetics research, Neurological disorders     

Health and disease as practical concepts: exploring function in context-specific definitions

Medicine, Health Care and Philosophy - Despite the longstanding debate on definitions of health and disease concepts, and the multitude of accounts that have been developed, no consensus has been...     

Attention to Background Strain Is Essential for Metabolic Research: C57BL/6 and the International Knockout Mouse Consortium

The International Knockout Mouse Consortium (IKMC) introduces its targeted constructs into C57BL/6N embryonic stem cells. However, breeding with a Cre-recombinase and/or Flp-recombinase mouse is required for the generation of a null allele with the IKMC cassette. Many recombinase strains are in the C57BL/6J background, resulting in knockout animals on a mixed strain background. This can lead to variability in metabolic data and the use of improper control groups. While C57BL/6N and C57BL/6J are derived from the same parental C57BL/6 strain, there are key genotypic and phenotypic differences between these substrains. Many researchers may not even be aware of these differences, as the shorthand C57BL/6 is often used to describe both substrains. We found that 58% of articles involving genetically modified mouse models did not completely address background strain. This review will describe these two substrains and highlight the importance of separate consideration in mouse model development. Our aim is to increase awareness of this issue in the diabetes research community and to provide practical strategies to enable researchers to avoid mixed strain animals when using IKMC knockout mice.     

Three-Dimensional Model-Based Segmentation in Echocardiography Using High Temporal Tissue and Blood Flow Information

Accurate 3-D surface segmentation is a challenging task in echocardiography because of the relatively low image quality. We introduce a new method for 3-D segmentation of the endocardium involving temporal decorrelation of echo signals originating from tissue and blood using radiofrequency (RF) signals acquired in 3-D Doppler mode. Temporal features were extracted in 3-D Doppler mode, where a sequence of RF lines is recorded for each image line. Each set of RF lines is highly correlated because of the high pulse repetition frequency. However, for high blood flow, the RF signals will decorrelate over time in contrast to the endocardium, which will remain relatively highly correlated over time. These decorrelation features permit differentiation between myocardial tissue and blood flow. We describe an implementation of a 3-D segmentation model in which temporal information is used as external constraint. The model was validated in a phantom and in vivo in healthy volunteers (n = 5). The phantom study revealed that the model successfully segmented the artificial blood lumen even for low flow velocity and illustrated the sensitivity of the segmentations to flow rate. In healthy volunteers, high Dice similarity indices indicate that 3-D segmentation of the endocardial border in vivo is feasible.     

Self‐perceived mouthfeel and physico‐chemical surface effects after chewing gums containing sorbitol and Magnolia bark extract

The European Food Safety Authority recognizes the contribution of sugar‐free chewing gum to oral health through increased salivation, clearance of food debris, and neutralization of biofilm pH. Magnolia bark extract is a gum additive shown to reduce the prevalence of bad‐breath bacteria but its effects on self‐perceived mouthfeel are unknown. This paper aims to relate the effects of sorbitol‐containing chewing gum, with and without Magnolia bark extract, on tooth‐surface hydrophobicity and salivary‐film composition with self‐perceived mouthfeel. In a crossover clinical trial, volunteers chewed sorbitol‐containing gum, with or without Magnolia bark extract added, three times daily during a 4‐wk time period. A subset of volunteers also chewed Parafilm as a mastication control. Oral moistness and tooth smoothness were assessed using questionnaires, and intra‐oral water‐contact angles were measured before, immediately after, and 60 min after, chewing. Simultaneously, saliva samples were collected, placed on glass slides, and the compositions of the adsorbed film were measured using X‐ray photoelectron spectroscopy. Chewing of gum, regardless of whether or not it contained Magnolia bark extract, improved self‐perceived mouthfeel up to 60 min, concurrent with a more hydrophilic tooth surface and an increased amount of O_1s electrons bound at 532.6 eV in salivary films. Chewing of Parafilm affected neither tooth‐surface hydrophobicity nor salivary‐film composition. Accordingly, adsorption of sorbitol, rather than the presence of Magnolia bark extract or increased salivation, is responsible for improved self‐perceived mouthfeel.