Clinical relevance of transforming growth factor alpha, epidermal growth factor receptor, p53, and Ki67 in colorectal liver metastases and corresponding primary tumors

To determine whether the expression of transforming growth factor alpha (TGF-alpha), its receptor (epidermal growth factor receptor [EGFr]), p53 nuclear protein, and proliferation influences prognosis of patients with liver metastases, a study was performed in 45 liver metastases and 33 corresponding primary colorectal carcinomas in patients referred for liver surgery. The expression of TGF-alpha, EGFr, p53 nuclear protein, and proliferation rate was correlated with clinicopathological characteristics and survival after partial liver resection. In liver metastases, TGF-alpha expression was low in 42%, intermediate in 35%, and high in 23%. TGF-alpha expression was higher in liver metastases derived from lymph node-positive primary carcinomas, in synchronous and in irresectable liver metastases compared with those derived from lymph node-negative primary carcinomas, metachronous, and resectable liver metastases. Nuclear p53 expression was found in 83% of primary tumors and 71% of liver metastases. p53 expression did not correlate with the various clinicopathological characteristics. Ki67 expression was not associated with clinicopathological characteristics in primary and metastatic tumors. In the 38 patients in whom a partial liver resection was performed, median survival was 25 months in patients with a higher TGF-alpha expression in the metastasis than in the primary tumor and 60 months in patients with comparable or lower TGF-alpha expression in the metastasis than in the primary tumor (P = .036). Median survival after liver resection was 21 months in patients with p53-negative liver metastases and 58 months in patients with p53-positive metastases (P = .043). By multivariate analysis, p53 and EGFr expression on liver metastases were the best predictors of disease-free survival after partial liver resection, with relative risks of 2.38 and 3.33, respectively. In patients with colorectal liver metastases, referred for liver surgery, a higher TGF-alpha expression is associated with unfavorable tumor characteristics, whereas p53 and absence of EGFr expression is associated with a better survival after partial liver resection.     

Motivation and organizational principles for anatomical knowledge representation: the digital anatomist symbolic knowledge base

OBJECTIVE: Conceptualization of the physical objects and spaces that constitute the human body at the macroscopic level of organization, specified as a machine-parseable ontology that, in its human-readable form, is comprehensible to both expert and novice users of anatomical information. DESIGN: Conceived as an anatomical enhancement of the UMLS Semantic Network and Metathesaurus, the anatomical ontology was formulated by specifying defining attributes and differentia for classes and subclasses of physical anatomical entities based on their partitive and spatial relationships. The validity of the classification was assessed by instantiating the ontology for the thorax. Several transitive relationships were used for symbolically modeling aspects of the physical organization of the thorax. RESULTS: By declaring Organ as the macroscopic organizational unit of the body, and defining the entities that constitute organs and higher level entities constituted by organs, all anatomical entities could be assigned to one of three top level classes (Anatomical structure, Anatomical spatial entity and Body substance). The ontology accommodates both the systemic and regional (topographical) views of anatomy, as well as diverse clinical naming conventions of anatomical entities. CONCLUSIONS: The ontology formulated for the thorax is extendible to microscopic and cellular levels, as well as to other body parts, in that its classes subsume essentially all anatomical entities that constitute the body. Explicit definitions of these entities and their relationships provide the first requirement for standards in anatomical concept representation. Conceived from an anatomical viewpoint, the ontology can be generalized and mapped to other biomedical domains and problem solving tasks that require anatomical knowledge.     

A blueprint for reducing turnover among nursing assistants: a Louisiana study

For decades, various exposes and reports have painted an unflattering portrait of the nursing home industry across the nation. Nursing homes in Louisiana have endured their fair share of publicity and criticism. The industry in this state has been accused of being preoccupied with profits rather than quality resident care. And, while there is much debate as to the validity of this complaint, there is solid agreement that competent and stable nursing assistants are the key to quality resident care. Unfortunately, the annual turnover rate of these essential employees ranges from 50% to 400%, nationally. This research identified the factors most responsible for the rate of turnover of nursing assistants employed in Louisiana nursing homes. Based upon the results of this study, pay, benefits, workload, and employee-employer relations, are not related to turnover. The analysis revealed that only three issues are associated with turnover--the number of beds, the number of beds per registered nurse, and the number of beds per social service worker. The message is clear: nursing home administrators must be very careful in stretching such resources. The number of beds assigned to an RN, and, in particular, the number of beds per social service worker are management issues that, if overextended, risk the turnover of nursing assistants.     

Data management for large community trials in Nepal

The current accessibility and sophistication of hardware and software has made it possible to design high-quality data management systems for community-based trials in resource-poor environments. We designed, implemented, and operated an effective data management system for the Nepal Nutrition Intervention Project Sarlahi (NNIPS), a placebo-controlled community trial to assess the impact of vitamin A supplementation on the preschool mortality of 38,000 children in the Sarlahi district of Nepal. A data center was established in Kathmandu, approximately 8 hr drive from the study area. The trial is now completed and over 200,000 forms have been processed. The majority of potential data discrepancies were identified and corrected by field workers during the interviews. Supervisors and forms editors located at the field office corrected most data errors. Once forms reach Kathmandu, the average number of data entry errors was 3.1 per 10,000 keystrokes for the eight data entry operators employed during the study. Extensive computerized checking of data during data entry found out-of-range, missing, or inconsistent data in only 1% of forms. Timely analysis of field worker performance provided ongoing feedback to supervisors and analysis for the Data Safety and Monitoring Committee, and for publication of results.     

A multicenter trial of 6-aminocaproic acid (Amicar) in the prevention of bleeding in infants on ECMO

BACKGROUND/PURPOSE: Intracranial hemorrhage (ICH), is a major source of morbidity and the leading cause of death in neonates treated with extracorporeal membrane oxygenation (ECMO). Anecdotal reports have suggested that epsilon-aminocaproic acid (EACA) can decrease the risk of ICH. The purpose of this study was to evaluate, in a multiinstitutional, prospective, randomized, blinded fashion, the effect of EACA on the incidence of hemorrhagic complications in neonates receiving ECMO. METHODS: All neonates (except congenital diaphragmatic hernia) who met criteria for ECMO at three institutions were eligible for enrollment. EACA (100 mg/kg) or placebo was given at the time of cannulation followed by 25 mg/kg/h for 72 hours. Bleeding complications, transfusion requirements, and thrombotic complications were recorded. Post-ECMO imaging included head ultrasound scan computed tomography (CT) scan, and duplex ultrasound scan of the inferior vena cava and renal vessels. RESULTS: Twenty-nine neonates were enrolled (EACA, 13 and placebo, 16). Five (17.2%) patients had a significant (grade 3 or larger) ICH. There was no statistical difference in the incidence of significant ICH in patients who received EACA (23%) versus placebo (12.5%). Septic patients accounted for all of the ICH in the EACA group. Thrombotic complications (aortic thrombus and SVC syndrome) developed in two patients from the placebo group. There was no difference in thrombotic circuit complications between groups. CONCLUSIONS: Our results suggest that the use of EACA in neonates receiving ECMO is safe but may not decrease the overall incidence of hemorrhagic complications.     

Optic flow processing in monkey STS: a theoretical and experimental approach

How does the brain process visual information about self-motion? In monkey cortex, the analysis of visual motion is performed by successive areas specialized in different aspects of motion processing. Whereas neurons in the middle temporal (MT) area are direction-selective for local motion, neurons in the medial superior temporal (MST) area respond to motion patterns. A neural network model attempts to link these properties to the psychophysics of human heading detection from optic flow. It proposes that populations of neurons represent specific directions of heading. We quantitatively compared single-unit recordings in area MST with single-neuron simulations in this model. Predictions were derived from simulations and subsequently tested in recorded neurons. Neuronal activities depended on the position of the singular point in the optic flow. Best responses to opposing motions occurred for opposite locations of the singular point in the visual field. Excitation by one type of motion is paired with inhibition by the opposite motion. Activity maxima often occur for peripheral singular points. The averaged recorded shape of the response modulations is sigmoidal, which is in agreement with model predictions. We also tested whether the activity of the neuronal population in MST can represent the directions of heading in our stimuli. A simple least-mean-square minimization could retrieve the direction of heading from the neuronal activities with a precision of 4.3 degrees. Our results show good agreement between the proposed model and the neuronal responses in area MST and further support the hypothesis that area MST is involved in visual navigation.     

Identification and biosynthesis of fibrinogen in human uterine cervix carcinoma cells

Fibrinogen has been detected in ME-180 human uterine cervix carcinoma cells, and synthesis of fibrinogen by ME-180 cells has been measured using [35S] L-methionine incorporation. Expression of mRNA for the B beta-chain of the fibrinogen in ME-180 cells has been identified by PCR-assisted mRNA amplification. The A alpha-, B beta-, and gamma-chains of fibrinogen synthesized by ME-180 cells were chemically and immunologically identical to those of plasma fibrinogen. These findings suggest that fibrinogen is present and synthesized in ME-180 human uterine cervix carcinoma cells, and that fibrinogen plays a role in these malignant tumor cells.     

Laparoscopic versus conventional appendectomy: a prospective randomized study

The discussion about laparoscopic appendectomy has increased since the introduction of this method. Randomized comparisons are still feasible, whereas this cannot be stated for other laparoscopic procedures (e.g., laparoscopic cholecystectomy). This randomized controlled trial included 170 patients. Open appendectomy was employed in 83 patients, and 87 were treated laparoscopically. The treatment groups were comparable regarding age, sex, Broca index, ASA classification, preliminary operations, and preoperative leucocytes. No statistically significant differences could be found with respect to surgical and general complications, operating time, consumption of analgesics and antibiotics, and return to work. The analysis revealed a statistically significant shorter hospital stay, a shorter time until return to normal physical activity, and a shorter duration of complaints for the laparoscopic group. We were unable to demonstrate any statistically significant advantage in using the open procedure.     

Pulsus tardus: its cause and potential limitations in detection of arterial stenosis

PURPOSE: To determine, with hydrodynamic experiments, the true cause of pulsus tardus, a Doppler waveform alteration that often occurs distal to an arterial stenosis. MATERIALS AND METHODS: A flow phantom was constructed with a pulsatile pump, interchangeable stenoses of varying degree, and interchangeable poststenotic segments of tubing with various degrees of compliance. With the transstenotic pressure drop held constant for each stenosis, Doppler waveforms were obtained before and after stenosis, while the degree of poststenotic vessel compliance was varied. RESULTS: The degree of pulsus tardus increased as the compliance of the poststenotic segment of vessel increased, independent of the transstenotic pressure drop. CONCLUSION: Poststenotic pulsus tardus is caused by the compliance of the poststenotic vessel wall in conjunction with the stenosis, which produces the tardus effect by damping the high-frequency components of the arterial waveform. This information will allow prediction of conditions that may produce false-positive or false-negative results when the tardus phenomenon is used to predict substantial upstream stenosis.