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The coming battle for customer information.

Companies collect information about customers to target valuable prospects more effectively, tailor their offerings to individual needs, improve customer satisfaction, and identify opportunities for new products or services. But managers' efforts to capture such information may soon be thwarted. The authors believe that consumers are going to take ownership of information about themselves and start demanding value in exchange for it. As a result, negotiating with customers for information will become costly and complex. How will that happen? Consumers are realizing that they get very little in exchange for the information they divulge so freely through their commercial transactions and survey responses. Now new technologies such as smart cards, World Wide Web browsers, and personal financial management software are allowing consumers to view comprehensive profiles of their commercial activities-- and to choose whether or not to release that information to companies. Their decision will hinge, in large part, on what vendors offer them in return for the data. Consumers will be unlikely to bargain with vendors on their own, however. The authors anticipate that companies they call infomediaries will broker information to businesses on consumers' behalf. In essence, infomediaries will be the catalyst for people to start demanding value in exchange for information about themselves. And most other companies will need to rethink how they obtain information and what they do with it if they want to find new customers and serve them better.

Community Participation↗

The clinical equipment coordinator: a new role in the hospital industry.

The increase in use, complexity, and cost of medical equipment requires a management response in both large and small hospitals. This paper describes the position of Clinical Equipment Coordinator (CEC) as it developed at Anaheim Memorial Hospital in Anaheim, California. The CEC can be highly effective in coordinating contract or shared services for a small hospital. In the larger hospital with an in-hospital Clinical or Biomedical Engineering Department, the CEC can take on the responsibilities of coordinating the services of the department. A detailed Job Description is presented along with typical forms and guidelines.

Biomedical Engineering↗

The limitations of decision trees and automatic learning in real world medical decision making.

The decision tree approach is one of the most common approaches in automatic learning and decision making. It is popular for its simplicity in constructing, efficient use in decision making and for simple representation, which is easily understood by humans. The automatic learning of decision trees and their use usually show very good results in various "theoretical" environments. The training sets are usually large enough for learning algorithm to construct a hypothesis consistent with the underlying concept. But in real life it is often impossible to find the desired number of training objects for various reasons. The lack of possibilities to measure attribute values, high cost and complexity of such measurements, unavailability of all attributes at the same time are the typical representatives. There are different ways to deal with some of these problems, but in a delicate field of medical decision making, we cannot allow ourselves to make any inaccurate decisions. We have measured the values of 24 attributes before and after the 82 operations of children in age between 2 and 10 years. The aim was to find the dependencies between attribute values and a child's predisposition to acidemia--the decrease of blood's pH. Our main interest was in discovering predisposition to two forms of acidosis, the metabolic acidosis and the respiratory acidosis, which can both have serious effects on child's health. We decided to construct different decision trees from a set of training objects, which was complete (there were no missing attribute values), but on the other hand not large enough to avoid the effect of overfitting. A common approach to evaluation of a decision tree is the use of a test set. In our case we decided that instead of using a test set, we ask medical experts to take a closer look at the generated trees. They examined and evaluated the decision trees branch by branch. Their comments on the generated trees can be found in this paper. The comments show, that trees generated from available training set mainly have surprisingly good branches, but on the other hand some are very "stupid" and no medical explanation could be found. Thereafter we can conclude, that the decision tree concept and automatic learning can be successfully used in real world situations, constrained with the real world limitations, but they should be used only with the guidelines of appropriate medical experts.

Acidosis↗

[Pregnancy and drug abuse].

The antenatal care of pregnant women with drug abuse is very complex and costly both in money and in time. The women often live under different circumstances than non-abusing women, and their personal and social resources are often very small. Collaboration between the hospital and the social system is essential in order to obtain a positive outcome of the pregnancy. Retrospective records of pregnancy, outcome and follow-up on 18 morphine-abusing women referred for delivery at Glostrup hospital in Copenhagen county over the three year period 1992-1994 are reported here. The study show the children are born in relatively good condition, although almost all needed postnatal detoxification, since their mothers was not able to stop their drug abuse during pregnancy. The pregnancy was with few complications because of tight antenatal care for these women. The study also shows a need for defining a common goal for the care of these women and their children and binding political commitments in order to obtain this goal.

Adult↗

Childhood acute lymphocytic leukemia.

Childhood ALL is a potentially curable disease. All children suffering from this ailment should be given an opportunity to live by receiving therapy aimed at permanent cure. The disease requires extensive, complex, and costly diagnostic study and treatment. Specialized care is more efficiently given in centers dedicated to treating patients with malignant diseases. The referring physicians are an essential part of the working team delivering care to the children with acute leukemia. Despite improved results, a significant number of patients fail to develop permanent remission. The risk of relapse after cessation of therapy is greatest in the first year and in patients given no specific CNS therapy. However, modern therapy produces a substantial number of long-term leukemia-free survivals in children with ALL, a majority of which persist after cessation of therapy. After cessation of therapy the quality of survival of the vast majority of patients is excellent.

Ambulatory Care↗

[Good clinical practice:impediment of source of progress?].

On the bases of the Declaration of Helsinki (1964), the law called Huriet-Sérusclat (1988) and several subsequent decrees have clearly defined the appropriate organization and management of clinical trials in France. The law on the Commission de l'informatique et des libertés (1978) and several European regulations have also to be taken into account. This extensive legal and regulatory system has been the source of a major improvement in the scientific quality of clinical trials and in the security of participating persons. Indirectly, it has also improved daily clinical care, as physicians have learned how to inform their patients and have been trained to use protocols and standard operative procedures. However, the legal and regulatory pressure has increased the cost and complexity of trials to such an extent that no clinician with his own resources is now able to be the sponsor of a trial involving more than a few patients. In addition to trials organized by pharmaceutical companies for drug development, health authorities in France and Europe should consider to support major clinical trials on therapeutic strategies with public health implications. A few examples can be acknowledged thus far, but a real policy remains to be defined.

Clinical Trials as Topic↗

Patient selection for assisted reproductive technology treatments.

Assisted reproductive technologies refer to procedures in which the oocyte is handled or manipulated in vitro before replacement, either as an oocyte or an embryo. Because of rapid advances in this area, infertile couples may seek direct referral for assisted reproductive treatments, instead of trying simpler measures such as ovulation induction and intrauterine insemination. It is important to establish whether these conventional infertility treatments are appropriate, as such treatments are generally safer, less stressful, and more affordable. On the other hand, subjecting infertile couples to unnecessary delay by offering inappropriate treatments-for example, ovulation induction for tubal infertility or intrauterine insemination for severe male-factor infertility-would reduce the overall chance of success because of the age-related decline in female fecundity. The choice of infertility treatments thus depends on a balance of factors: the chance of pregnancy without treatment; the chance with simpler and safer, but less successful, infertility treatments; or the chance with the more complex and costly, but more effective, assisted reproductive treatments. The factors that should be taken into consideration include the age of the woman, the duration of infertility, the causes of infertility, the availability and cost of alternative treatments, and-most importantly-the acceptability.

Anovulation↗

Isolated hypoxic hepatic perfusion (IHHP) using balloon catheter techniques: from laboratory to the clinic towards a percutaneous procedure.

BACKGROUND/AIMS: The success of and our extensive experience with TNF alpha-based isolated limb perfusions in patients with unresectable extremity soft tissue sarcomas made us explore the possibilities for a similar approach for the treatment of hepatic metastases. After experience with the classic surgical isolated hepatic perfusion in pigs and in patients, we concluded that the classic surgical approach was associated with serious drawbacks i.e., magnitude of the procedure with morbidity, lack of repeatability of the procedure, complexity and costs. These problems were addressed in a program aimed at developing a repeatable method of isolated perfusion of the liver with minimally invasive techniques. METHODOLOGY: We validated the methodology of isolated hypoxic hepatic perfusion using balloon catheter techniques in pigs. RESULTS: The excellent pharmacokinetic profile of the procedure, resulting in very high regional drug concentrations and negligible systemic drug concentrations, allowed us to move on to the clinic and start to study and further develop this method in a phase I-II study using the drug melphalan, in patients with irresectable hepatic metastases. CONCLUSIONS: We aim to develop step by step a fully percutaneous approach for isolated hypoxic hepatic perfusion.

Aged↗

[Triple therapy of short-term with azithromycin, amoxycillin and omeprazole for the eradication of Helicobacter pylori].

BACKGROUND: The high cost and complexity of therapeutic schemes for the eradication of Helicobacter pylori has stimulated the search of simpler and cheaper treatment options. AIM: To evaluate the efficacy of 3 days of azithromycin 500 mg od, 7 days of amoxycillin 750 mg tid and omeprazole, 20 (Group A) or 40 mg (Group B) on randomization, as a treatment for Helicobacter pylori infection in patients with endoscopically diagnosed peptic ulcer. METHODS: H. pylori status of peptic ulcer patients was pathologically confirmed by the examination of five gastric biopsies using the Giemsa stain and by rapid urease testing in two gastric biopsies. H. pylori status was reassessed not less than 28 days after completing treatment. Adverse events and compliance were evaluated. RESULTS: Fifty four patients (29 men, 25 women, mean age 48 years) were enrolled, 28 in Group A and 27 in Group B. Per protocol the infection was cured in 58.8% of patients (30/51; 95% CI: 45-73%). On an intention to treat basis, H pylori infection was cured in 55%. Minor side effects including diarrhea and nausea were reported by 32% of patients. Ninety-five per cent of patients consumed more than 95% of prescribed medications. H. pylori was successfully eradicated in 61% of group A and 57% of group B patients (p = NS). CONCLUSION: Short term therapy with azithromycin was poorly effective in curing H. pylori infection. The compliance was excellent. Increasing Omeprazole from 20 to 40 mg/day did not improve treatment effectiveness.

Amoxicillin↗

[Left ventricular stimulation in treatment of heart failure].

SEARCH FOR AN ALTERNATIVE TREATMENT: The concept of stimulating the ventricle to improve heart function in patients with severe heart failure is an old one, but the first published series was reported about 10 years ago and provided encouraging results that lead to numerous other studies. A PROMISING TECHNIQUE: Excepting a few patients with a long PR, stimulation of the right ventricle is ineffective or even deleterious. Stimulation of the lateral region of the left ventricle has produced some undeniably favorable and sometimes even spectacular improvement in hemodynamic performances. Permanent stimulation of both ventricles or the left ventricle produces an overall clinical improvement in patients with severe heart failure (NYHA III or IV) and major left intraventricular conduction disorders (QRS > 140 ms). These results have been recently confirmed in a prospective randomized trial. CAREFUL OPEN QUESTIONS: There is no fully satisfactory explanation for the improvement which, it is important to note, does not occur in all patients. A more homogeneous contraction of the left ventricle certainly plays a fundamental role. Resynchronization of the two ventricles with dual stimulation is more complex and costly and remains to be evaluated. One crucial question is currently being examined: what is the effect of stimulation on the high mortality in these patients?

Heart Failure↗

The value of sonography for estimation of liver volume by using a simple geometric formula ascertained in cadaveric livers.

Accurate assessment of liver size and its volume are important. However, as the clinical methods do not produce reliable results especially when the liver is shrunken, and the previous attempts to accurately assess liver volume by radio-isotopes, CT scans and computer assisted ultrasonography have not gained popularity due to high cost and complex techniques, the need to devise a simpler technique for estimation of liver volume continues. In doing so, we estimated volume of 10 cadaveric livers by water displacement technique to serve as the reference value. Thereafter, assuming the shape of liver like a right-angled pyramid, we calculated its volume by a simple geometric formula of '1/2 abc'. However, a reduction of 15% was made from this to compensate for depression on the inferior surface of liver. This method was subsequently implemented to assess liver volume of 14 healthy individuals and 20 patients of fulminant hepatic failure (FHF) by using ultrasonography. Our findings revealed smaller liver volume in Indians as compared to the reported Western figures, and a significantly smaller liver volume in females as compared to males. The liver volume of 6 FHF patients who died was significantly smaller (696.5 +/- 143.5 cm3) as compared to that of the 14 FHF patients who survived (1083 +/- 365.3 cm3). Moreover, mortality rate was 100 per cent in 3 patients of FHF who showed markedly shrunken globular liver with a liver volume of less than 500 cm3. Thus, a markedly reduced liver size in FHF patients suggests a poor prognosis. However, since the number of FHF patients in the present series is small, it is our contention that a larger series is mandatory to confirm the findings of the present study.

Adult↗

Analysis of the postprandial lipid metabolism: use of a 3-point test.

OBJECTIVES: The oral fat load tests used to study postprandial lipemia are complex and costly and time consuming. A simplified fat load test could be more convenient and more appropriate in routine clinical practice because of the number of lipid determinations required. RESEARCH DESIGN AND METHODS: We evaluated the capacity of a postprandial test model that reduced the number of blood samples taken in thirty three normal weight controls and 17 normotriglyceridemic obese patients (study 1), 10 normolipidemic type 2 diabetic patients and 7 healthy controls (study 2), and 10 hyperlipidemic type 2 diabetic patients studied before and after hypolipidemic therapy (study 3). Blood samples were taken before and up to 8 hours after giving the oral fat load containing retinol. Triglyceride (TG) and retinyl palmitate (RP) concentrations in the plasma, chylomicrons (CM) and non-chylomicron (nCM) fractions were measured. Postprandial lipid responses using conventional area under the curves (AUCc using 5 to 7 lipid determinations) were compared to a 3-point test that uses only three sample points to predict the area under the curve (AUCp: triglycerides at T0, triglycerides at average peak-time (T4), and triglycerides at T8). RESULTS: The AUCc and AUCp for triglycerides and retinyl palmitate were highly correlated in each of the groups and whatever the lipid subfraction (r=0.664 - 0.995, p<0.0001). When incremental AUC (iAUC) were used, the coefficients of correlation for triglycerides remained highly significant between iAUCc and iAUCp (r=0.718 - 0.979, p<0.01 - 0.0001). The same trend of differences was found between cases and controls when AUCp was used instead of AUCc. The means of differences between AUCc and AUCp for triglyceride values were small (0.34 - 0.74 mmol/L.h), and the confidence intervals were acceptable considering the range of the AUCs values (5.60 to 79.8 mmol/L.h for plasma triglycerides). CONCLUSIONS: We found that data obtained with a simplified model of AUC using only 3 points to analyse postprandial lipemia are well correlated with those obtained by conventional AUC, and that the AUCp allows to the same conclusions as AUCc when healthy subjects were compared to patients with altered postprandial metabolism. Thus AUCp may be a good evaluation of the AUCc, and the simplified 3-point protocol may well be used and suitable for studies on large groups of subjects who are eligible for an oral fat load test.

Area Under Curve↗

On the history of New York Medical College.

The history of New York Medical College reflects three distinct trends in the development of medical education: the rise and fall of homeopathy, the input of civic leaders (in this case, William Cullen Bryant) and the uneasy relationship between medical schools and hospitals caused by the dramatic increase in the complexity and cost of hospital care.

History, Modern 1601-↗

Can malaria DNA vaccines on their own be as immunogenic and protective as prime-boost approaches to immunization?

To develop a multi-stage, multi-antigen, multi-immune response-inducing vaccine against malaria we have focused on DNA vaccines because of their simplicity of construction and modification, ease of mixing, and effectiveness in inducing CD8+ T cell responses. DNA malaria vaccines induce CD8+ T cell dependent protection in mice and CD8+ CTL in rhesus monkeys and humans after intramuscular needle administration. Clinical trials in normal, healthy humans are in progress or planned, assessing alternative methods and routes of administration, and the capacity of a plasmid expressing human GM-CSF to enhance the protective efficacy of a five-gene liver-stage malaria vaccine. In mice, we have demonstrated that priming with the combination of DNA plasmids encoding a Plasmodium yoelii protein and murine GM-CSF and boosting with recombinant poxvirus expressing the same P. yoelii protein induces a 30-fold increase in antigen-specific antibodies, a 10-fold increase in antigen-specific IFN-gamma spot forming cells, a significant (p<0.05) increase in protection, and the capacity to reduce the dosage of DNA by 10-100 fold, compared to immunizing with DNA alone. In Aotus monkeys priming with DNA and boosting with recombinant protein in adjuvant is more protective than homologous priming and boosting with either DNA or recombinant protein in adjuvant. Clinical trials are now planned using these immunization strategies. Because of the complexity and cost of the heterologous regimens, we are working to make DNA vaccination alone as immunogenic and protective as the prime-boost approach. Our most encouraging findings have resulted from altering codon usage from the highly A+T rich P. falciparum native sequence to that more closely resembling mammalian sequences. Although much progress is required for the development of a vaccine that provides sustainable protective immunity against malaria, a strategy using DNA vaccine technology as a core component of such a vaccine is promising.

Animals↗

Efficient and predictable recovery of viruses from water by small scale ultrafiltration systems.

Current methods to concentrate viruses from large volumes of water are prone to inconsistent results and are costly and complex procedurally. Ultrafiltration can utilize size exclusion rather than adsorption and (or) elution to concentrate viruses and, therefore, may offer greater flexibility in developing methods that can provide more consistent recoveries among different viruses and widely varying water conditions. Two small scale ultrafiltration systems (hollow fiber and tangential flow) were tested with a virus suspended in 2 L of reagent grade, tap, ground, or surface water. Three model viruses were used (bacteriophages PP7 and T1 and poliovirus) to compare and characterize the recovery of viruses with the two ultrafiltration systems. Pretreatment of the ultrafilters with blocking agents and the use of elution agents can serve to prevent viral adsorption to the filter surface or to elute bound virus and keep viral agents suspended in the retentate. The use of a blocking and elution step concentrated viruses (>60% recovery) from widely varying water qualities, including surface water, such that a single method can be used to efficiently concentrate viruses from all of the water types tested. Both ultrafiltration systems appear to be able to efficiently recover viruses; however, the hollow fiber systems provided slightly better results in the 2-L volumes tested.

Acrylic Resins↗

The importance of large, high quality clinical databases in nephrology.

While clinical trials constitute an undisputed standard, they are not perfect because they are focused on a well defined segment of patients with a given disease. Generalizability is a problem with these studies because the experimental setting often differs substantially from everyday clinical practice. Clinical files are traditionally the main source of information for clinical medicine. The quality of recorded information in clinical files is often unsatisfactory. Yet clinical files are data-rich and ought to be considered as a valuable resource, particularly when clinical information is stored in electronic format. Clinicians have already started to construct very large, high quality clinical databases. Outcome research based on high quality data retrieved from well organized and exhaustive clinical files is bound to become increasingly important. Standardization is fundamental for these projects to be successful. The task may be daunting but worth while; due to complexity and cost the randomised clinical trial is unlikely to remain the only source of information on which to base clinical decisions about treatments.

Clinical Trials as Topic↗

Wet weather water quality modelling of a Portuguese urban catchment: difficulties and benefits.

This paper discusses the use of water quality deterministic modelling together with an integrated approach to assess the impact of urban stormwater discharges into ephemeral watercourses, based on the study of a Portuguese catchment. The description of the main aspects, difficulties and benefits found during data collection and model calibration and verification is presented, and the associated uncertainties and errors discussed. Experimental results showed a strong short- and long-term impact of sewer discharges on rivers, and confirmed deposition, resuspension and transport of pollutants as important processes for the water quality. However, the resuspension of riverbed sediment pollutants during storms was probably more significant than the direct impact of the urban discharges. The HydroWorks model was used since it allows for the calculation of pollutant build-up on catchment surfaces and in gully pots, their wash-off, and the deposition and erosion of sediments in sewers. However, it uses several constants, which could not be independently calibrated, increasing the uncertainty already associated with the data. River flows have quite different magnitude from the sewer system overflows, which, together with the difficulties in evaluating river flow rates, makes the integrated modelling approach rather complex and costly.

Cities↗