The application of the bioelectric recognition assay for the detection of human and plant viruses: definition of operational parameters

The bioelectric recognition assay (BERA) is a novel biosensory method based on a unique combination of a group of cells, their immobilization in a matrix that preserves their physiological functions and the expression of the cell interaction with viruses as a change in electrical properties. A BERA sensor consists of an electroconductive, tube-like probe containing components of immobilized cells in a gel matrix. Cells are selected to specifically interact with the virus under detection. In this way, when a positive sample is added to the probe, a characteristic, 'signature-like' change in electrical potential occurs upon contact between the virus and the gel matrix. In the present study, we demonstrate that BERA can be used for the detection of viruses in humans (hepatitis C virus) and plants (tobacco and cucumber viruses) in a remarkably specific, rapid (1-2 min), reproducible and cost-efficient fashion. The sensitivity of the virus detection with BERA (0.1 ng) is equal or even better than with advanced immunological, cytological and molecular techniques, such as the reverse transcription polymerase chain reaction. Moreover, a good storability of the sensors can be achieved without affecting their performance. The potential use of portable BERA biosensors in medicine, for mass screening purposes, as well as for the detection of biological warfare agents without prior knowledge of a specific receptor-molecule interaction is discussed.

Antidepressant use and the risk of breast cancer: a non-association

OBJECTIVE

Animal studies have suggested that some antidepressant medications may act as breast tumor promoters and recent epidemiologic studies of antidepressant use and breast cancer outcomes in humans have also reported such associations.

DESIGN

Retrospective cohort study.

STUDY POPULATION

38,273 women who filled a prescription for any of a number of antidepressants and 32,949 who filled a prescription for any other medication during 1989-1991; all were > or =20, enrolled in Medicare, Medicaid or the Pharmaceutical Assistance to the Aged and Disabled (PAAD) programs of New Jersey, and free of evidence of breast cancer.

DATA COLLECTION

Antidepressant use was assessed over a period lasting up to 24 months. Subjects were followed for a maximum of 7.5 years; those who had a first diagnosis of breast cancer in the New Jersey Cancer Registry at least 3 months after their index date were considered incident breast cancer cases. Other covariates, including demographic, clinical, and health care utilization variables were also assessed. MAIN OUTCOME OF INTEREST: Adjusted hazard ratio (HR) of developing breast cancer, based on multivariable proportional hazards models.

RESULTS

Use of antidepressants was unrelated to the development of breast cancer (adjusted HR = 1.04; 95% CI 0.87-1.25). No elevated risks were found for specific antidepressants, including agents found to be breast tumor promoters in animal studies, as well as drugs thought to be associated with breast cancer in prior epidemiologic studies. There was no suggestion that breast cancer risks were increased with more intensive use of antidepressants or that antidepressant use is associated with a more severe stage of cancer at diagnosis.

CONCLUSIONS

Despite recent reports from much smaller epidemiologic studies or laboratory animals, these results provide reassurance that antidepressant use is not associated with the development of breast cancer.

Cost/benefit analysis of open tracheotomy, in the or and at the bedside, with percutaneous tracheotomy

OBJECTIVES/HYPOTHESIS

(1) To determine whether percutaneous dilational tracheotomy (PDT), open tracheotomy in the operating room (OT/OR), and open tracheotomy at the bedside (OT/BS) are equally safe; and (2) to determine which procedure was most cost effective.

STUDY DESIGN

Retrospective review of patient medical records and billing data.

METHODS

Any adult patient (>20 y of age) on the medical or surgical services at Penn State Milton S. Hershey Medical Center who required a tracheotomy, elective or emergent, from September 1996 to July 1997 was included. The decision to perform OT in the OR, PDT, or OT at BS was made by the attending surgeon independent of this study. Each patient's course after tracheotomy was reviewed. All complications, perioperatively or postoperatively, for up to 10 days were documented. The complications were divided into two groups: major and minor. Determination of patient cost used surgical billing and OR materials staff records. The necessary equipment and staff for each procedure was determined, and an itemized cost list was retrospectively developed for a typical PDT, OT in OR, or OT at BS. The P values were calculated with the Cochran-Mantel-Haenszel (CMH) chi(2) test of association.

RESULTS

All procedures were equally safe, with PDT being the most cost effective.

CONCLUSION

This report confirms the results of several studies demonstrating that PDT, OT in the OR, and OT at the BS are equally safe; PDT appears to be most cost effective. Our analysis, however, does reveal several options for decreasing the cost of bedside tracheotomy to allow this procedure to be even more cost effective than PDT.

Bioelectric recognition assay (BERA)

A novel biosensory method has been developed for the determination of various chemical and biological molecules by assessing their electrophysiological interactions with a group of cells and cell components immobilized in a gel matrix that preserves their 'physiological' functions. The method was applied for the detection of: (i) hepatitis C virus in human blood samples; (ii) plant viruses; and (iii) a herbicide (glyphosate) in aqueous solutions. It was able to rapidly (assay time 3-5 min) and specifically detect the molecules in question at a concentration lower than 100 pg/ml, among other compounds f similar structure. The potential use of BERA biosensors for a rapid and cost-efficient molecule determination without prior knowledge of a specific receptor-molecule interaction is discussed.

Finding incident breast cancer cases through US claims data and a state cancer registry

OBJECTIVE

With the increasing availability of automated health-care data, new methods are available to screen large populations for the presence of cancer diagnoses. However, it is crucial to evaluate how completely incident cancer cases can be ascertained using these data sources.

METHODS

We used capture-recapture techniques to estimate the total number of incident breast cancer cases occurring within one state during a 3-year period. We then compared the ascertainment of these cases by the following two data sources: claims for breast cancer surgery recorded in Medicaid and Medicare data vs a cancer registry in the same state.

RESULTS

Medicaid-Medicare breast cancer surgery claims identified 68% of the total estimated number of incident breast cancer cases while cancer registry data identified 78%. Case ascertainment improved markedly to 91% when both registry and Medicare-Medicaid data sources were used together. The sensitivity of ascertainment was lower for Medicaid-Medicare data among those aged under 65 and non-white; ascertainment was lower for the registry among women who were aged under 65, poor, and non-white.

CONCLUSIONS

Combining health insurance claims data with a population-based cancer registry improved the identification of incident cases of breast cancer, and may be particularly useful among demographic groups found to be at highest risk of under-ascertainment such as younger women, the poor, and racial minorities.

Rapid mobilization of murine hematopoietic stem cells with enhanced engraftment properties and evaluation of hematopoietic progenitor cell mobilization in rhesus monkeys by a single injection of SB-251353, a specific truncated form of the human CXC chemokine GRObeta

SB-251353 is an N-terminal truncated form of the human CXC chemokine GRObeta. Recombinant SB-251353 was profiled in murine and rhesus monkey peripheral blood stem cell mobilization and transplantation models. SB-251353 rapidly and transiently mobilized hematopoietic stem cells and neutrophils into the peripheral blood after a single subcutaneous injection. Transplantation of equivalent numbers of hematopoietic stem cells mobilized by SB-251353 into lethally irradiated mice resulted in faster neutrophil and platelet recovery than stem cells mobilized by granulocyte colony-stimulating factor (G-CSF). A single injection of SB-251353 in combination with 4 days of G-CSF administration resulted in augmented stem and progenitor cell mobilization 5-fold greater than G-CSF alone. Augmented stem cell mobilization could also be demonstrated in mice when a single injection of SB-251353 was administered with only one-day treatment with G-CSF. In addition, SB-251353, when used as a single agent or in combination with G-CSF, mobilized long-term repopulating stem cells capable of hematopoietic reconstitution of lethally irradiated mice. In rhesus monkeys, a single injection of SB-251353 induced rapid increases in peripheral blood hematopoietic progenitor cells at a 50-fold lower dose than in mice, which indicates a shift in potency. These studies provide evidence that the use of SB-251353 alone or in combination with G-CSF mobilizes hematopoietic stem cells with long-term repopulating ability. In addition, this treatment may (1) reduce the number of apheresis sessions and/or amount of G-CSF required to collect adequate numbers of hematopoietic stem cells for successful peripheral blood cell transplantation and (2) improve hematopoietic recovery after transplantation.

The role of water in dialysis: why does it need to be more than "clean"?

The importance of maintaining a high quality water system cannot be stressed enough. Many reports have been published that link chronic inflammation to microbial and endotoxin contamination of water used for dialysate. While the use of ultra filters on individual dialysis machines will reduce the bacterial and endotoxin levels in dialysate, the efficacy of the ultrafilters will be decreased if the levels of bacterial and endotoxin contamination are too high. The individual components of a water system must be treated as a whole and all policies and procedures pertaining to the water system must be strictly adhered to in order to maintain the water system at peak condition.

Evaluation of the Functional Assessment of Cancer Therapy-General Questionnaire (FACT-G) in a South American Spanish speaking population

There is an increasing interest by health care providers, not only in the effectiveness of cancer treatments, but also in patients' quality of life (QOL). The objective of the present study is to validate the Functional Assessment of Cancer Therapy-General (FACT-G) Version 2 as a measure of the QOL in a sample of 140 Uruguayan patients with cancer of varied sites, at different stages of the disease and under different forms of treatment. Reliability of the FACT-G was evaluated and showed high coefficients (Cronbach's alpha) in each of the subscales and in the total questionnaire score. It was also capable of discriminating among different groups of patients. We conclude that the FACT-G is a brief and easy to use questionnaire, that showed acceptable reliability and validity and good feasibility for use as a research instrument among Uruguayan cancer patients.

Delivering health care services in the community: a multidisciplinary perspective

The Canadian health care system has shifted away from its traditional emphasis on acute care in-patient services, to increasing dependence on community-based services. A major implication is that education for work in this new environment will need to be reconceptualized, and those already in the system will have to examine their assumptions and alter their approach to patient care. This paper reports the results of a study which examines the attitudes, educational preparation, skills sets, and perceptions of "community" among social workers, occupational therapists, nurses and physiotherapists. The results should inform social work and other health educators about relevant theoretical and practical preparation for work in an environment which increasingly emphasizes multiple skills, community partnerships and coordinated care.

Failure of evidence-based medicine in the treatment of hypertension in older patients

OBJECTIVE

Throughout the 1990s, the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure recommended initial antihypertensive therapy with a thiazide diuretic or a beta-blocker based on evidence from randomized, controlled trials, unless an indication existed for another drug class. The committee also recommended beta-blockers in hypertensive patients with a history of myocardial infarction (MI), and angiotensin-converting enzyme (ACE) inhibitors in patients with congestive heart failure (CHF). Our objective was to determine whether prescribing practices for older hypertensive patients are consistent with evidence-based guidelines.

METHODS

We examined prescription patterns from January 1, 1991 through December 31, 1995 for 23,748 patients 65 years or older with a new diagnosis of hypertension from the New Jersey Medicaid program and that state's Pharmacy Assistance for the Aged and Disabled program (PAAD). We linked drug use data with information on demographic variables and comorbid medical conditions.

RESULTS

During the study period, calcium channel blockers were the most commonly prescribed initial therapy for hypertension (41%), followed by ACE inhibitors (24%), thiazide diuretics (17%), and beta-blockers (10%). Eliminating patients with diabetes mellitus, CHF, angina, or history of MI did not substantially affect these results. Overall, initial use of a thiazide declined from 22% in 1991 to 10% in 1995, while initial use of a calcium channel blocker increased from 28% to 43%, despite publication during these years of studies demonstrating a benefit of thiazides in older patients. Only 15% of older hypertensive patients with a history of MI received beta-blockers.

CONCLUSIONS

Prescribing practices for older hypertensive patients are not consistent with evidence-based guidelines. Interventions are needed to encourage evidence-driven prescribing practices for the treatment of hypertension.

Neonatal outcome of preimplantation genetic diagnosis by polar body removal: the first 109 infants

CONTEXT

Our center developed the technique of preimplantation genetic diagnosis (PGD) by sequential polar body removal (PBR) for the diagnosis of Mendelian disorders and aneuploidies. This study examines the obstetric and neonatal outcome of the first 109 live births after PGD by PBR.

OBJECTIVE

To determine if there were any observable effects of PGD by PBR on perinatal morbidity and mortality, birth defects, and growth parameters.

DESIGN

Data on perinatal outcome were gathered for the first 109 infants by parental reporting and confirmed by telephone interview and chart review when indicated. In infants >6 months old, a follow-up telephone interview was performed establishing the developmental milestones attained by the child.

SETTING

A research center conducting an institutional review board-approved research protocol in PGD.

PATIENTS

All patients who had PGD by PBR who had clinical pregnancies.

MAIN OUTCOME MEASURES

Gestational age, mode of delivery, perinatal mortality, birth weight, birth length, the presence of birth defects, and developmental milestones.

RESULTS

There was no significant decrease in birth length or weight, or the frequency of small for gestational age infants. No specific pattern of birth defects was observed.

CONCLUSION

Thus far, there are no observable detrimental effects of PGD by PBR on children born after the procedure.

Strategies for improving comorbidity measures based on Medicare and Medicaid claims data

Claims-based measures of comorbid illness severity have generally relied on the diagnoses listed for a single hospitalization. Unfortunately, such diagnostic information is often limited because patients have not been hospitalized during periods of interest, because of incomplete coding of diagnoses on claims forms, or because listed diagnoses represent complications of the hospitalization rather than pre-existing comorbid conditions. To address these limitations, we developed and tested four comorbidity index scores for patients with breast cancer, each based on different sources of health services claims from Medicare and Medicaid: hospitalization for breast cancer surgery; outpatient care prior to the hospitalization; other inpatient care prior to the hospitalization; and all sources combined. Varying the number and type of sources of diagnostic information yielded only very small improvements in the prediction of mortality at 1 and 3 years. Surprisingly, even simpler measures of comorbidity (crude number of diagnoses) and of prior health care utilization (total days spent in the hospital) performed at least as well in predicting mortality as did the more complex index scores which assigned points and weights for specific conditions. The greatest improvement in explanatory power was observed when another source of clinical information (cancer stage derived from a population-based cancer registry) was used to supplement claims information. Expanding the source of claims diagnoses and focusing on time periods prior to an index hospitalization are insufficient for substantially improving the explanatory power of claims-based comorbidity indices. Other improvements suggested by our results should include: increasing the completeness and accuracy of claims diagnoses; supplementing diagnoses with health care utilization information in claims data; and supplementing claims data with other sources of clinical information.

Drinking water turbidity and gastrointestinal illness in the elderly of Philadelphia

STUDY OBJECTIVE

To investigate the association between drinking water quality and gastrointestinal illness in the elderly of Philadelphia.

DESIGN

Within the general population, children and the elderly are at highest risk for gastrointestinal disease. This study investigates the potential association between daily fluctuations in drinking water turbidity and subsequent hospital admissions for gastrointestinal illness of elderly persons, controlling for time trends, seasonal patterns, and temperature using Poisson regression analysis.

SETTING AND PARTICIPANTS

All residents of Philadelphia aged 65 and older in 1992-1993 were studied through their MEDICARE records.

MAIN RESULTS

For Philadelphia's population aged 65 and older, we found water quality 9 to 11 days before the visit was associated with hospital admissions for gastrointestinal illness, with an interquartile range increase in turbidity being associated with a 9% increase (95% CI 5.3%, 12.7%). In the Belmont service area, there was also an association evident at a lag of 4 to 6 days (9.1% increase, 95% CI 5.2, 13.3). Both associations were stronger in those over 75 than in the population aged 65-74. This association occurred in a filtered water supply in compliance with US standards.

CONCLUSIONS

Elderly residents of Philadelphia remain at risk of waterborne gastrointestinal illness under current water treatment practices. Hospitalisations represent a very small percentage of total morbidity.

Trends in specialized surgical procedures at teaching and nonteaching hospitals

Teaching hospitals are the principal site of many specialized surgical procedures. The recipients of these procedures tend to be younger, male, and nonwhite and tend to reside in either the poorest or the most affluent neighborhoods. Although the numbers of these procedures performed at major teaching hospitals increased dramatically between 1989 and 1995, they accounted for only a modest proportion of hospital discharges and patient days. Concentration of specialized surgical procedures in major teaching hospitals will likely continue. This trend has implications not only for these hospitals but for health care purchasers, policymakers, medical educators, and clinical researchers as well.

Hemoglobin/O2 systems: using short-lived intermediates for mechanistic discrimination

The kinetics of the reaction of hemoglobin with molecular oxygen, in which rapid mixing is followed by a very fast temperature jump, is numerically simulated. Four different mechanisms are considered. In two of them, oxygen reacts with the alpha-chains first, in the other two with the beta-chains first. Furthermore, either the third or the fourth measured (Adair) dissociation constant is composed of the product of a local dissociation constant and an allosteric interconversion constant. We explore whether these alternative mechanisms may be distinguished experimentally. We show that reaction steps not resolvable by rapid mixing can be resolved by chemical relaxation at appropriate points in time. Discrimination under experimental conditions is possible at higher oxygen concentrations (above 100 microM), but high resolution in time and concentration amplitude are required.

Minimally invasive surgical treatment of female stress urinary incontinence

The purpose of this study was to evaluate the safety and efficacy of a new minimally invasive surgical procedure for the treatment of female stress urinary incontinence (SUI). Four miniature bone anchors, each attached to a suture, are inserted transvaginally into the retropubic bone using an inserter on each side of the urethra without opening the vaginal mucosa. Tying the suture on each ipsilateral side creates colposuspension, as is the aim of previously described procedures such as the Marshall-Marchetti-Krantz. Sixty-one women (mean age 52+/-SD 9.9 years) with a mean follow-up of more than 12 months (range 12-30 months) were treated for SUI. Fifty patients (82%) are dry, 7 (14%) reported great improvement and 4 are considered surgical failures. The data presented suggest that our new minimally invasive procedure provides an effective treatment for female SUI. Its main advantages over other procedures are the transvaginal approach and short operating time.

Dreams of personality disordered subjects

Dreams provide access to underlying personality structure, defensive and adaptive functions, and they elucidate the psychological forces that lead to overt symptomatic behavior. Two hundred three dreams of 39 personality disordered patients were factor analyzed and compared with Hall and Van de Castle's normative data (Hall C, Van de Castle RI [1966] The content analysis of dreams. New York: Appleton-Century-Crofts). Results included a five-factor solution that sheds light on some core issues of the dreamers. Comparisons between the groups resulted in the personality-disordered group demonstrating more estrangement in their dreams, fewer interactions, and more emotionality. In their interactions, they demonstrated a lower ratio of aggressive interactions yet a higher tendency to view themselves as the aggressor. Results are related to theoretical literature on personality and defensive styles, mostly from a psychodynamic perspective.