SEARCH · Search PubMed

Results for “Data Sources”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources

PubMed2001

Cell and molecular biology of chemical allergy.

OBJECTIVE: The objective of this review is to provide current approaches to gain increased understanding of the molecular basis of chemical allergenicity. Chemical allergy refers to an allergic reaction to a low molecular weight agent (ie, <1 kD). The symptoms and pathology of chemical asthma resemble those of allergy to larger sized agents, such as pollens, weeds, and danders. The differences relate to mechanisms of disease. To stimulate an immune response, low molecular weight chemicals function as haptens and bind to carrier macromolecules. This article focuses on the chemical reactions and physicochemical characteristics of chemical allergens. DATA SOURCES: Data were obtained from published clinical reports and from the Documentation of Threshold Limit Values (1998) published by the American Congress of Governmental Industrial Hygienists. RESULTS: In vitro studies indicate the stoichiometric reaction of some chemical allergens with glutathione and the subsequent transfer of the allergen from glutathione to other nucleophiles. Computer-generated structure-activity relationship models have been developed for chemicals that induce respiratory allergy. The models, based on physicochemical properties of the agents, have high sensitivity and specificity. CONCLUSIONS: The structure-activity relationship model suggests that chemical binding is the essential feature of chemical allergens. Their in vivo reactions with thiols may result in glutathione deficiency with consequent alteration in cellular reduction-oxidation (redox) status, release of cytokines, and promotion of the T helper cell 2 phenotype. Prevention of permanent disease is dependent on periodic medical surveillance of affected workers. When detected early, the disease can frequently be reversed.

Allergens↗

PubMed2001

Indoor pollution and its impact on respiratory health.

LEARNING OBJECTIVES: This overview discusses the respiratory complications of indoor air pollution, emphasizing the most common pollutants that individuals are likely to encounter outside the workplace. DATA SOURCES: Data were obtained from a review of the recent literature. STUDY SELECTION: The expert opinion of the author was used to select and synthesize relevant data on this multifaceted subject. RESULTS: There have been a number of studies documenting an association between exposure to indoor allergens and development of both sensitization and asthma in children. In addition to classic allergens, chemical indoor air pollution may also exert an adverse effect on both the upper and lower respiratory tract by a variety of nonimmunologic, irritative mechanisms. CONCLUSIONS: Our understanding of the adverse effects of indoor air pollution on health and comfort has broadened in recent years. It has supplied a credible framework for developing and implementing a variety of control strategies.

Air Pollution, Indoor↗

PubMed2001

Methods and effectiveness of indoor environmental control.

LEARNING OBJECTIVES: The purpose of this review is to describe recommended methods of decreasing exposure to indoor allergens. DATA SOURCES: Data were obtained from published studies and reviews. STUDY SELECTION: The reviewed studies met these criteria: 1) measurement of environmental allergens; 2) selection of participants with clearly defined allergic airway disease confirmed by detection of allergen-specific immunoglobulin E; and 3) clearly defined clinical and environmental outcomes. The studies were conducted as controlled clinical trials and the results between treated and control groups were compared with appropriate statistics. RESULTS: The results of these studies show that installing allergen proof encasings and washing bedding frequently reduces house-dust mite exposure by 10-fold or more and significantly improves clinical measures of asthma. Washing pets reduces allergen levels temporarily. Excluding the pet from the bedroom while installing allergen-proof encasings and operating air cleaner reduces airborne allergens although having no significant effect on allergic symptoms. Cockroach populations can be controlled for over 6 months and allergens can be reduced with controlled pesticide application and cleaning, but clinical correlates have not been reported. Methods to improve adherence to environmental control measures have not been tested but effective methods can be recommended from literature on medication adherence. CONCLUSIONS: For patients allergic to indoor allergens, reasonable recommendations include installation of allergen-impermeable encasings, frequent laundering of bedding, removing furred pets from the home, and controlling of cockroach populations with effective pesticides using the principles of integrated pest management.

Air Pollution, Indoor↗

PubMed2001

Fungi: toxic killers or unavoidable nuisances?

OBJECTIVES: This discussion is focused on the many roles of fungi in human health, and also to put the mycotoxin literature into perspective. DATA SOURCES: Data are derived from the literature referenced in PubMed from the National Library of Medicine, earlier references in the authors' reprint collection, and ongoing research. Studies for review were either selected from the peer-reviewed literature or from standard texts that are well recognized in the field. RESULTS: The review yielded many studies of the role of fungi in allergic disease, but none that systematically documented such a role for mycotoxins or fungal volatiles. Many case studies were found, but none of these unequivocally document a cause/effect relationship between mycotoxin exposure by inhalation and human disease in residential, school, or office settings. CONCLUSIONS: The review led to the conclusion that that the primary result from fungal exposure is allergic disease, and that the evidence for inhalation disease resulting from mycotoxin exposure in residential and office settings is extremely weak.

Administration, Inhalation↗

PubMed2001

Stachybotrys: relevance to human disease.

LEARNING OBJECTIVES: Recent public concern about the danger of environmental fungi has focused attention on one particular mold, Stachybotrys. The purpose of this review is to examine and critique the published literature on Stachybotrys for objective scientific and clinical evidence of disease caused by the presence of this fungal organism in the environment. DATA SOURCES: Data were obtained from all published research and reviews of Stachybotrys indexed in MEDLINE since 1966. STUDY SELECTION: The publications used for this review were those that contained information about human health effects of this microorganism. The critique of these publications is the author's. RESULTS: Stachybotrys is a minor component of the indoor mycoflora, found on certain building material surfaces in water-damaged buildings, but airborne spores are present in very low concentrations. Published reports fail to establish inhalation of Stachybotrys spores as a cause of human disease even in water-damaged buildings. A possible exception may be mycotoxin-caused pulmonary hemorrhage/hemosiderosis in infants, although scientific evidence to date is suggestive but not conclusive. Based on old reports ingestion of food prepared from Stachybotrys-contaminated grains may cause a toxic gastroenteropathy. No convincing cases of human allergic disease or infection from this mold have been published. CONCLUSIONS: The current public concern for adverse health effects from inhalation of Stachybotrys spores in water-damaged buildings is not supported by published reports in the medical literature.

Air Pollution, Indoor↗

PubMed2000

The effect of windspeed on pollen and spore counts collected with the Rotorod Sampler and Burkard spore trap.

BACKGROUND: A recent review article presented conflicting evidence concerning the relationship between the Rotorod Sampler's particle collection efficiency and windspeed. Conventional wisdom holds that its collection efficiency is not affected by windspeed; experimental data paint a mixed picture. OBJECTIVES: This brief addendum will present additional data concerning the relationship between the Rotorod's collection efficiency and windspeed. This information will be contrasted with similar data for the Burkard spore trap. DATA SOURCE: Data obtained from an obscure technical report published by Ogden et al. in 1969 will be assessed. RESULTS: The Rotorod's collection efficiency appeared to be greatest at moderate windspeeds; lower efficiencies occurred at both lower and higher windspeeds. Maximum changes in collection efficiency ranged from 29% to 39% over the six windspeeds employed. The Burkard exhibited the opposite relationship between collection efficiency and windspeed. Collection efficiency was lowest at moderate windspeeds and higher at both lower and higher windspeeds. Maximum changes in collection efficiency ranged from 38% to 142%. CONCLUSIONS: Four principal conclusions emerged. First, these newly rediscovered data demonstrate that the Rotorod's collection efficiency is affected by windspeed. These results appear to overturn the conventional wisdom which holds that this device is insensitive to wind. Second, the Rotorod is less affected by windspeed than the Burkard. The maximum change in collection efficiency uncovered for the former device was 39%; this represented the minimum maximum change for the latter device. Third, the Rotorod and Burkard are affected by windspeed in fundamentally different ways. The former device's collection efficiency is greatest at moderate windspeeds and lower at both lower and higher windspeeds. The opposite effect occurs with the latter device. Last, the previous two findings may partially explain some of the differences in particle recovery by the two devices noted in the parent publication. Figures and equations presented in this addendum indicate which circumstances are likely to produce these differences.

Air Pollution↗

PubMed2002

Masqueraders of angioedema and urticaria.

OBJECTIVES: Reading this article will remind the reader that some patients presenting with complaints of urticaria and angioedema may not have urticaria or angioedema at all, but may have other causes, often unusual, sometimes treatable. It will also increase the reader's ability to recognize masqueraders of angioedema, urticaria, and facial swelling thought to be angioedema. DATA SOURCES: Data for this article come mainly from the authors' personal experiences and selected references to illustrate points made in the article. STUDY SELECTION: The criteria used are patients and articles from the authors' experiences that illustrate the point of this article that patients presenting with urticaria and angioedema may have other diseases and some of these are treatable. RESULTS: The objectives will be met by patient presentations plus pertinent literature review. CONCLUSIONS: Some patients presenting as angioedema and urticaria have swelling and skin lesions attributable to other causes. Although they are uncommon, they are sometimes treatable. Not all patients referred to an allergist for angioedema have angioedema.

Acne Vulgaris↗

PubMed2000

Plant genome databases: from references to inference tools.

Plant genome databases play an important role in the archiving and dissemination of data arising from the international genome projects. Recent developments in bioinformatics, such as new software tools, programming languages and standards, have produced better access across the Internet to the data held within them. An increasing emphasis is placed on data analysis and indeed many resources now provide tools allied to the databases, to aid in the analysis and interpretation of the data. However, a considerable wealth of information lies untapped by considering the databases as single entities and will only be exploited by linking them with a wide range of data sources. Data from research programs such as comparative mapping and germplasm studies may be used as tools, to gain additional knowledge but without additional experimentation. To date, the current plant genome databases are not yet linked comprehensively with each other or with these additional resources, although they are clearly moving toward this. Here, the current wealth of public plant genome databases is reviewed, together with an overview of initiatives underway to bind them to form a single plant genome infrastructure.

Computational Biology↗

PubMed1992

Hepatocyte culture systems for artificial liver support: implications for critical care medicine (bioartificial liver support).

OBJECTIVE: The primary purpose of this review article is to familiarize critical care practitioners with newly developing techniques of hybrid artificial liver support. Implantable and extracorporeal hepatocyte culture systems are emphasized based on their current experimental and clinical status. DATA SOURCES: Data used to prepare this document were obtained from the authors' personal files, as well as the computerized MEDLINE database. Medical headings used include: liver, artificial organs, cell culture, growth hormones, extracellular matrix, and transplantation. Only articles published in English have been cited. STUDY SELECTION: All studies are discussed in which hepatocyte culture systems have been used to support human patients with liver failure. All studies reported the patient's condition before therapy, duration of therapy, and outcome after therapy in order to be included in this review. Since the number of clinical trials is small at this time, animal studies were used to demonstrate application of other systems in the treatment of experimentally induced liver failure. Similar selection criteria were used to select animal studies for review. All initially identified human studies met these selection criteria. DATA EXTRACTION: Independent extraction by multiple observers. DATA SYNTHESIS: Liver failure, resulting from infection, drugs, or as a part of the multiple organ failure syndrome, remains a major cause of morbidity, mortality, and resource allocation. Current therapy is limited to supportive care, along with liver transplantation. Because of these therapeutic limitations, hybrid artificial liver systems have been proposed for temporary and long-term hepatic support. Several animal studies and a small number of preliminary human studies indicate that hepatocyte culture systems are capable of supporting nearly all essential hepatic functions and may supply biologically active substances that promote regeneration and repair of the damaged liver being supported. Hybrid systems may be constructed from materials that serve as immunoprotective barriers against host defenses. CONCLUSIONS: During the past decade, important progress has been made with hybrid artificial liver support systems. Cell culture technology has progressed sufficiently so that an artificial liver, composed of metabolically active hepatocytes, may be a potential reality in the foreseeable future. Both implantable and extracorporeal artificial liver support systems have been developed to provide metabolic support during acute liver failure, or to serve as a bridge to solid organ transplantation. Implantable hepatocyte systems, however, require a prolonged period for intraperitoneal engraftment and vascularization, not typically available to patients with acute liver failure. For this reason, extracorporeal hybrid designs offer the greatest hope for on-line treatment of acute liver failure. Such systems are entering the final stages of animal testing.

Animals↗

PubMed1993

Introduction of new technology into critical care practice: a history of HA-1A human monoclonal antibody against endotoxin.

OBJECTIVES: HA-1A, a monoclonal antibody against endotoxin, was thought to be effective in treating patients with Gram-negative sepsis. Because of this possibility, many clinicians felt obligated to use the drug and assumed that its product license application would be approved by the U.S. Food and Drug Administration (FDA). Nevertheless, the efficacy of HA-1A was not conclusively demonstrated by a first clinical trial. The FDA rejected the product license application and requested a second clinical trial, which was suspended after excess mortality was noted in patients treated with HA-1A. This review of the history of the drug was prepared to provide clinicians and sepsis investigators with information about HA-1A and, by extension, the process by which new technology is introduced into critical care practice. DATA SOURCES: Data used to prepare this review were obtained from the author's personal files as well as the computerized MEDLINE database. STUDY SELECTION: Studies were selected for their relevance to the history of HA-1A and their relevance to the introduction of potentially useful medical technology. DATA EXTRACTION: The author extracted all applicable data. DATA SYNTHESIS: Although the first clinical trial of HA-1A suggested that the drug was effective in treating patients with Gram-negative bacteremia with or without shock, further analysis by the FDA indicated a benefit only for bacteremic patients with shock. Furthermore, the original study design was not followed, leading in part to the FDA's refusal of the product license application. Concern also was raised over the issue of identifying which patients should receive HA-1A and the cost of the drug, which would have put it past the reach of some American hospitals and thereby, would have conflicted with the ethical principle of social justice. Finally, the second trial suggested that HA-1A might be harmful. CONCLUSIONS: Due to the FDA's action, the issues raised about HA-1A, and the results of the two clinical trials, clinicians should not use the drug. The history of HA-1A provides insights about how new technology is and will be introduced into critical care practice.

Antibodies, Monoclonal↗

PubMed1995

Physicians do not have a responsibility to provide futile or unreasonable care if a patient or family insists.

OBJECTIVE: This article was written to argue that physicians are not ethically obligated to provide care which they consider futile, unreasonable, or both, either voluntarily or in response to patient or surrogate demands. DATA SOURCES: Data used to prepare this article were drawn from published articles, including original investigations, position papers and editorials in the author's personal files. STUDY SELECTION: Articles were selected for their relevance to the subjects of medical ethics, the concepts of futility and medical reasonableness, case law, and healthcare reform. DATA EXTRACTION: The author extracted all applicable data. DATA SYNTHESIS: Physicians may feel obligated to provide care in all clinical circumstances due to the single master view of medicine and the ethical principle of autonomy. However, care may be considered futile according to several definitions of that word, including that which describes futile treatment as something that does not benefit the patient as a whole. Furthermore, care may be considered unreasonable if it is excessive and not generally agreed upon. Physician refusal to provide futile or unreasonable care is supported by the ethical principles of nonmaleficence, beneficence, and distributive justice. The last principle is particularly relevant in the current climate of healthcare reform. CONCLUSIONS: Although the issue of physician refusal of requested care has not been resolved by case law or legal statute, it is supported by compelling ethical principles. Physicians are not ethically required to provide futile or unreasonable care, especially to patients who are brain dead, vegetative, critically or terminally ill with little chance of recovery, and unlikely to benefit from cardiopulmonary resuscitation.

Adult↗

PubMed1996

Cardiopulmonary resuscitation: what cost to cheat death?

OBJECTIVES: To review the various outcomes from cardiopulmonary resuscitation (CPR), the factors that influence these outcomes, the costs associated with CPR, and the application of cost-analyses to CPR. DATA SOURCES: Data used to prepare this article were drawn from published articles and work in progress. STUDY SELECTION: Articles were selected for their relevance to the subjects of CPR and cost-analysis by MEDLINE keyword search. DATA EXTRACTION: The authors extracted all applicable data from the English literature. DATA SYNTHESIS: Cost-analysis studies of CPR programs are limited by the high variation in resources consumed and attribution of cost to these resources. Furthermore, cost projections have not been adjusted to reflect patient-dependent variation in outcome. Variation in the patient's underlying condition, presenting cardiac rhythm, time to provision of definitive CPR, and effective perfusion all influence final outcome and, consequently, influence the cost-effectiveness of CPR programs. Based on cost data from previous studies, preliminary estimates of the cost-effectiveness of CPR programs for all 6-month survivors of a large international multicenter collaborative trial are $406,605.00 per life saved (range $344,314.00 to $966,759.00), and $225,892.00 per quality-adjusted-life-year (range $191,286.00 to $537,088.00). CONCLUSIONS: Reported outcome from CPR has varied from reasonable rates of good recovery, including return to full employment to 100% mortality. Appropriate CPR is encouraged, but continued widespread application appears extremely expensive.

Cardiopulmonary Resuscitation↗

PubMed1999

Prevention and management of overwhelming postsplenectomy infection--an update.

OBJECTIVES: To review the diagnosis and management of overwhelming postsplenectomy infection and to discuss various preventative measures. DATA SOURCES: Data used to prepare this article were drawn from published articles and work in progress. STUDY SELECTION: Articles were selected for relevance to the subject after location by a MEDLINE key word search. DATA EXTRACTION: The literature was reviewed to summarize the etiology and pathophysiology of postsplenectomy sepsis. Preventative strategies were outlined with a particular emphasis on education, immunoprophylaxis, and chemoprophylaxis. DATA SYNTHESIS: Although physicians have become increasingly aware of overwhelming postsplenectomy infection in children, many remain unaware of the risk to asplenic or hyposplenic adults who may have no underlying medical problems. Recent studies have shown that many patients who have had splenectomies have had neither appropriate vaccinations nor teaching that would explain the lifelong nature of their risk. The increasing incidence of penicillin-resistant pneumococci represents a major area of therapeutic and prophylactic concern. The identification of Howell-Jolly bodies on a peripheral blood smear should alert physicians to the need for follow-up to document possible hyposplenism. Attention has focused on a three-pronged attack to this problem, including education, immunoprophylaxis, and chemoprophylaxis. CONCLUSIONS: Overwhelming postsplenectomy infection should be largely preventable if appropriate precautions are taken. Physicians need to know of the spectrum of diseases associated with hyposplenism and how patients noted to have Howell-Jolly bodies should be investigated. They should also be aware of appropriate guidelines for management of patients with asplenia or hyposplenism.

Adult↗

PubMed2000

Comparison of risk-adjustment systems for the medicaid-eligible disabled population.

OBJECTIVE: The objective of this study was to compare 2 approaches for subjecting capitation rates for disabled Medicaid-eligible patients in managed care plans to risk adjustment, the Disability Payment System (DPS) and the Ohio Prior Expenditure System (OPES). DESIGN: This was a retrospective cohort. SETTING AND SUBJECTS: The subjects were 157,142 nonelderly disabled individuals eligible for > or =1 month during state fiscal year 1995 (SFY95) for a 3-county Ohio Medicaid managed care demonstration project. DATA SOURCE: Data were from the Ohio Medicaid eligibility and fee-for-service claims files. ANALYSIS: As per OPES policy, individuals were classified by the duration of their eligibility in SFY93 as "old" eligibles (> or =6 months) or "new" eligibles (<6 months). Published relative payment weights for each system were adjusted and used to predict SFY95 expenditures in a budget-neutral comparison. Measures were variance in SFY95 expenditures explained by predicted payments (R2) and predictive ratios (predicted payment/actual SFY95 expenditure). Individuals with HIV/AIDS and hematological conditions, who enrolled disproportionately across the demonstration counties, were analyzed separately. RESULTS: Of the 157,142 individuals, 56.4% were new eligibles; 40.1% of the old eligibles had no claims-documented chronic disease diagnosis in the baseline year. The overall R2 was 0.091 with OPES and 0.057 with DPS. Neither system predicted >1% of individual-level expenditures for new eligibles. OPES severely underpaid for eligibles in the top percentile of predicted expenditures; DPS had mixed results. DPS predicted SFY95 expenditures substantially better than OPES for the enrollment bias categories. CONCLUSIONS: Before Medicaid programs move to full-risk capitation for disabled populations, better risk-adjustment methods are needed, especially for eligible patients with little claims experience, high predicted expenditures, or enrollment-bias conditions.

Adolescent↗

PubMedDate not supplied

Social and professional support for pregnant and parenting women.

PURPOSE: A literature review to contrast the role of social and professional support in improving maternal and infant outcomes in pregnant and parenting women. In addition, recommendations are made for future research and policy and program development concerning support needed by pregnant and parenting women. DATA SOURCES: Data were limited to published studies. Searches of computerized databases, hand searches of journals, and backward searches from reference lists of studies were conducted. Nursing, medicine, psychology, public health, sociology, and social work literatures were searched (CINAHL, Medline, PsychLit, Social Sciences Abstracts, Social Sciences Citation, and Social Work Abstracts). STUDY SELECTION: The studies focused on outcomes of social support and professional support to pregnant and parenting women. The samples of the studies included pregnant women and parenting women up to 2 years postpartum. Studies reviewed were conducted in the United States or Canada and included maternal and/or infant outcomes. All ages and races of pregnant and parenting women were considered. DATA EXTRACTION: Data were extracted from each study concerning the theoretical framework, variables, sample, design, measuring instruments, interventions, and outcomes. DATA SYNTHESIS: Social support outcomes were summarized in paragraphs while a table was used to summarize professional support intervention outcomes. CONCLUSIONS: Outcomes associated with specific support interventions should be clearly identified, informed by theory, and include assisting the pregnant and parenting woman to improve her social support.

Clinical Competence↗

PubMedDate not supplied

Paraprofessional support for pregnant & parenting women.

PURPOSE: To review evidence regarding the role of paraprofessional support in improving maternal and infant outcomes in pregnant and parenting women. Although support provided by significant others (social support), by professionals, and by paraprofessionals are frequently considered together in literature reviews, this is inappropriate because the components of the support in each case differ. DATA SOURCES: Data were limited to published studies. Searches of computerized databases (CINAHL, Medline, PsychLit, Social sciences abstracts, Social sciences citation, and Social work abstracts), hand searches of journals, and backward searches from reference lists of studies were conducted. Nursing, medicine, psychology, public health, sociology, and social work literatures were searched. STUDY SELECTION: The studies included had statistically significant outcomes of paraprofessional support to pregnant and parenting women. Studies were published in 1985 or later, were conducted in the United States or Canada, and included maternal and/or infant outcomes. DATA EXTRACTION: Data were extracted from each study concerning the theoretical framework, design, sample, measuring instruments, interventions, and outcomes. CONCLUSIONS: Programs providing paraprofessional support to childbearing women are clearly providing an important service, but empirical evidence is not adequate to determine which specific paraprofessional program works for a specific population of women to achieve the best long-term outcomes for both women and children. Although proponents of paraprofessional support programs for pregnant and parenting women have reported some successes, more data are needed. Researchers should continue to conduct well-designed and controlled studies to compare outcomes from the three types of support. Nurses in practice should build on services provided by paraprofessionals in order to meet women's need for support and to achieve desired outcomes.

Community Health Services↗

PubMed1988

Adolescent hopefulness in illness and health.

Hopefulness is believed to be a significant element in the human response to illness, but its clinical impact has not been documented due to conceptual and operational difficulties. This article generates a definition of hopefulness from well and ill adolescents. The study's conceptual orientation included the beliefs that hope is a contributing factor in health maintenance and is especially vital for individuals experiencing life-threatening illness. Grounded theory methodology was used. Interviews, observations and health records were data sources. Data were analyzed during the cross-comparative method. A panel approach was used to assess the reliability and validity of the induced categories. Theoretical saturation on a definition was achieved. Adolescents with cancer had a dimension in the definition not found in the other two groups. The added dimension had a focus on "others" in contrast to only "self."

Adolescent↗

PubMed2004

Screening of athletes: Australian experience.

OBJECTIVE: To present an overview of medical screening of athletes in Australia DATA SOURCES: Data was obtained from Australian sports physicians involved in elite national and professional programs. DATA SYNTHESIS/METHODS: The status in Australia of medical screening and in particular the Pre-participation Examination (PPE) was reviewed. RESULTS: The PPE as practised in North America is not performed in Australia. However medical screening of elite national level and professional athletes is widely practised. A variety of screening methods is used. The medical screening protocol recently developed on behalf of the Australasian College of Sports Physicians (ACSP) is presented. CONCLUSIONS: Medical screening of high performance athletes takes place regularly in Australia. Valuable information may be obtained from this process. The extent of the screening is limited by financial and time constraints. The proposed protocol is a basis for a comprehensive medical screening, but can be adapted depending on the individual and the sport played.

Australia↗