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PubMed1988

Education to prevent AIDS: prospects and obstacles.

A number of obstacles thwart effective education to prevent AIDS in the United States. These include the biological basis and social complexity of the behaviors that must be changed, disagreement about the propriety of educational messages to prevent AIDS, uncertainty about the degree of risk to the majority of Americans, and dual messages of reassurance and alarm from responsible officials. Long-term protection of an individual from infection requires extreme changes in risk-taking behavior. Partial shifts toward safer practices may be epidemiologically important in retarding the rate and extent of spread of infection. Though some striking changes in behavior have occurred, especially in homosexual populations in areas with high prevalence of AIDS, educational efforts to date have succeeded more in raising awareness and knowledge about AIDS than in producing sufficient changes in behavior. The United States has yet to mount a nationwide comprehensive, intensive, and targeted education program to prevent AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Genetic variation in arthropod vectors of disease-causing organisms: obstacles and opportunities.

An overview of the genetic variation in arthropods that transmit pathogens to vertebrates is presented, emphasizing the genetics of vector-pathogen relationships and the biochemical genetics of vectors. Vector-pathogen interactions are reviewed briefly as a prelude to a discussion of the genetics of susceptibility and refractoriness in vectors. Susceptibility to pathogens is controlled by maternally inherited factors, sex-linked dominant alleles, and dominant and recessive autosomal genes. There is widespread interpopulation (including intercolony) and temporal variation in susceptibility to pathogens. The amount of biochemical genetic variation in vectors is similar to that found in other invertebrates. However, the amount varies widely among species, among populations within species, and temporally within populations. Biochemical genetic studies show that there is considerable genetic structuring of many vectors at the local, regional, and global levels. It is argued that genetic variation in vectors is critical in understanding vector-pathogen interactions and that genetic variation in vectors creates both obstacles to and opportunities for application of genetic techniques to the control of vectors.

Animals↗
PubMed2004

Intrinsic obstacles to human immunodeficiency virus type 1 coreceptor switching.

The natural evolution of human immunodeficiency virus type 1 infection often includes a switch in coreceptor preference late in infection from CCR5 to CXCR4, a change associated with expanded target cell range and worsened clinical prognosis. Why coreceptor switching takes so long is puzzling, since it requires as few as one to two mutations. Here we report three obstacles that impede the CCR5-to-CXCR4 switch. Coreceptor switch variants were selected by target cell replacement in vitro. Most switch variants showed diminished replication compared to their parental R5 isolate. Transitional intermediates were more sensitive to both CCR5 and CXCR4 inhibitors than either the parental R5 virus or the final R5X4 (or rare X4) variant. The small number of mutations in viruses selected for CXCR4 use were distinctly nonrandom, with a dominance of charged amino acid substitutions encoded by G-to-A transitions, changes in N-linked glycosylation sites, and isolate-specific mutation patterns. Diminished replication fitness, less-efficient coreceptor use, and unique mutational pathways may explain the long delay from primary infection until the emergence of CXCR4-using viruses.

Amino Acid Sequence↗
PubMed1999

Neonatal screening for congenital hypothyroidism in Mexico: experience, obstacles, and strategies.

OBJECTIVE: To report the experience, obstacles, and strategies of screening for congenital hypothyroidism. SETTING: Newborns in Mexico. METHODS: Thyroid stimulating hormone (TSH) was measured by enzyme immunoassay using commercial kits in 1,140,364 newborns. RESULTS: There were 464 positive cases, of whom 299 (64.4%) were girls. 236 (50.9% showed ectopic nodules, 202 (43.5%) thyroid agenesis, 21 (4.5%) dyshormonogenesis, and 5 (1.1%) an unclassified goitre. The false positive rate was 0.024% and there were 11 false negative results. Currently, 600,000 (26%) of the 2,300,000 newborns are screened. This percentage has been increased in recent years by taking samples from cord blood and will be increased further by starting congenital hypothyroidism screening at social security units and by midwives screening infants born at home. CONCLUSIONS: Mental retardation in infants in developing countries can be reduced by neonatal screening, and carefully planned strategies can steadily extend the benefits of screening.

Blood Specimen Collection↗
PubMed2004

Exact lattice calculations of dispersion coefficients in the presence of external fields and obstacles.

We present a study of the field-dependent dispersion coefficient of point-like particles in various 2D overdamped systems with obstructions (periodic, percolating, and trapping distributions of obstacles). These calculations profit from the synthesis of a newly proposed Monte Carlo algorithm--the first such algorithm that correctly reproduces the free dispersion coefficient in the presence of finite external fields--and an asymptotically exact calculation technique. The resulting method efficiently produces algebraic and numerical results without the need to actually perform Monte Carlo simulations. When compared to such simulations, our exact method features a negligible computational cost and exponentially small errors. Utilizing the power of this numerical method, we engage in comprehensive parametric analysis of several model systems, revealing very subtle effects that would otherwise be swamped by statistical errors or incur prohibitive computational costs. The unified framework presented here serves as a template for further applications of lattice random-walk models of biased diffusion.

Algorithms↗
PubMed2004

Learning obstacle avoidance with an operant behavior model.

Artificial intelligence researchers have been attracted by the idea of having robots learn how to accomplish a task, rather than being told explicitly. Reinforcement learning has been proposed as an appealing framework to be used in controlling mobile agents. Robot learning research, as well as research in biological systems, face many similar problems in order to display high flexibility in performing a variety of tasks. In this work, the controlling of a vehicle in an avoidance task by a previously developed operant learning model (a form of animal learning) is studied. An environment in which a mobile robot with proximity sensors has to minimize the punishment for colliding against obstacles is simulated. The results were compared with the Q-Learning algorithm, and the proposed model had better performance. In this way a new artificial intelligence agent inspired by neurobiology, psychology, and ethology research is proposed.

Avoidance Learning↗
PubMed1975

Obstacles in the treatment of dying patients.

Theory and practice in the management of the dying patient have moved forward in the past two decades. However, the author believes the benefits of this progress have not reached a large segment of the population of dying patients--those individuals who have a higher level of psychopathology or are from a lower socioeconomic group. Obstacles in the treatment of such patients are described and illustrated by case histories; the author makes specific recommendations related to the care of these more difficult cases.

Adult↗
PubMed1982

Integrating health and mental health services: historical obstacles and opportunities.

Historically, health and mental health services have been separated by a variety of forces, including specialization; ideological, attitudinal, and financial barriers; the professionalization of psychiatry; and functional and organizational differentiation. Recently, several models of integration and coordination have been proposed. If they are to succeed, health planners will have to be aware of the essential ingredients of interorganizational cooperation and work to eliminate the obstacles to integration of health and mental health services.

Comprehensive Health Care↗
PubMed1989

Obstacles to integrating disabled students in a "two-roof" elementary school.

This article describes a 5-year effort to integrate special and regular students on a campus where special and regular education students are housed in separate but adjacent facilities with separate administrators. Observational data and questionnaires revealed almost total segregation at the end of 3 years. An intensive intervention program, Project L.E.A.D., generated promising short-term movement toward integration, but there were few enduring effects. Physical, social, and psychological barriers created by the two-roof school erect almost insurmountable obstacles to integration. Future efforts should concentrate on building one-roof schools with a single facility and administration.

Adolescent↗
PubMed2005

The GuideLine Implementability Appraisal (GLIA): development of an instrument to identify obstacles to guideline implementation.

BACKGROUND: Clinical practice guidelines are not uniformly successful in influencing clinicians' behaviour toward best practices. Implementability refers to a set of characteristics that predict ease of (and obstacles to) guideline implementation. Our objective is to develop and validate a tool for appraisal of implementability of clinical guidelines. METHODS: Indicators of implementability were identified from the literature and used to create items and dimensions of the GuideLine Implementability Appraisal (GLIA). GLIA consists of 31 items, arranged into 10 dimensions. Questions from 9 of the 10 dimensions are applied individually to each recommendation of the guideline. Decidability and Executability are critical dimensions. Other dimensions are Global, Presentation and Formatting, Measurable Outcomes, Apparent Validity, Flexibility, Effect on Process of Care, Novelty/Innovation, and Computability. We conducted a series of validation activities, including validation of the construct of implementability, expert review of content for clarity, relevance, and comprehensiveness, and assessment of construct validity of the instrument. Finally, GLIA was applied to a draft guideline under development by national professional societies. RESULTS: Evidence of content validity and preliminary support for construct validity were obtained. The GLIA proved to be useful in identifying barriers to implementation in the draft guideline and the guideline was revised accordingly. CONCLUSION: GLIA may be useful to guideline developers who can apply the results to remedy defects in their guidelines. Likewise, guideline implementers may use GLIA to select implementable recommendations and to devise implementation strategies that address identified barriers. By aiding the design and operationalization of highly implementable guidelines, our goal is that application of GLIA may help to improve health outcomes, but further evaluation will be required to support this potential benefit.

Benchmarking↗
PubMed2004

Lost in Translation: Obstacles to Translational Medicine.

When we launched the Journal of Translational Medicine a few months ago, we were interested primarily in exploring scientific consideration of this discipline. However, as editors of JTM, we have been contacted almost daily to discuss the problems faced by scientists and clinicians around the world who are challenging the traditional boundaries of science and medicine. Through these conversations, we have learned that translational medicine is in fact "lost in translation," inspiring much angst, many promises and some Federal appropriations. However, little has been done to substantively promote this important field. Authoritative reviews on the subject are available to the interested reader 1234567. In this article, we will address JTM's "constituency" to report what we've learned about the obstacles to translational medicine from the myriad of phone conversations and e-mail interactions.

Editorial↗
PubMed2005

A prototype power assist wheelchair that provides for obstacle detection and avoidance for those with visual impairments.

BACKGROUND: Almost 10% of all individuals who are legally blind also have a mobility impairment. The majority of these individuals are dependent on others for mobility. The Smart Power Assistance Module (SPAM) for manual wheelchairs is being developed to provide independent mobility for this population. METHODS: A prototype of the SPAM has been developed using Yamaha JWII power assist hubs, sonar and infrared rangefinders, and a microprocessor. The prototype limits the user to moving straight forward, straight backward, or turning in place, and increases the resistance of the wheels based on the proximity of obstacles. The result is haptic feedback to the user regarding the environment surrounding the wheelchair. RESULTS: The prototype has been evaluated with four blindfolded able-bodied users and one individual who is blind but not mobility impaired. For all individuals, the prototype reduced the number of collisions on a simple navigation task. CONCLUSION: The prototype demonstrates the feasibility of providing navigation assistance to manual wheelchair users, but several shortcomings of the system were identified to be addressed in a second generation prototype.

Journal Article↗
PubMed2006

Living donor islet transplantation, the alternative approach to overcome the obstacles limiting transplant.

We performed the world's first successful living donor islet transplantation for unstable diabetes. A total of 408,114 islet equivalents were isolated from half a living pancreas and transplanted immediately to the recipient who was a 27-year-old female. The donor was a 56-year-old female in good health, mother of the recipient. The islets functioned immediately, and the recipient was weaned completely from insulin on the 22nd posttransplant day, and has maintained excellent glycemic control since. The donor was discharged on the 18th postoperative day with normal oral glucose tolerance test and without complications. Living donor islet transplantation could cure one insulin-dependent diabetes mellitus patients with a single donor. There are some advantages in the living donor islet transplantation: (a) living donor can alleviate the issue of donor shortage; (b) highly potent islets can be isolated from a living donor; and (c) the recipient can be treated with immunosuppressant and controlled blood glucose level tightly prior to the transplantation. These are important factors in overcoming the obstacles limiting islet transplantation. We believe that the living donor islet transplantation may become an additional option in treating insulin-dependent diabetes.

Adult↗
PubMed1995

Common obstacles to the daily functioning of pediatric traumatically brain injured patients: perceptions of caregivers and psychologists.

Common difficulties encountered by patients with pediatric traumatic brain injuries (referred to hereafter as pediatric TBI patients) were identified, and the congruence between caregiver and professional perceptions of these problems was examined. Forty-seven caregivers identified 118 obstacles experienced in the care of their pediatric TBI patients. Another sample of 46 caregivers cross-validated these problems by rating each for its frequency and difficulty. Items were tank ordered by their composite score, a derived measure obtained for each item by cross-multiplying the frequency and difficulty ratings. Twenty psychologists who work with pediatric TBI patients also rated each of the 118 problem situations. A modest correlation (tau = .28, p < .001) between the two groups' rank orders of the problem situations, although significant, suggests that there are discrepancies between caregiver and professional perceptions of problem situations. Items perceived as most common and difficult by caregivers often received far lower ratings by psychologists and vice versa. The results suggest that carefully evaluating individual patient concerns may contribute to more efficient use of professional resources and improved patient education and follow-up care.

Activities of Daily Living↗
PubMed2003

Obstacles in the diagnosis and treatment of syphilitic amyotrophy.

The authors describe a case of syphilitic amyotrophy in a 37-year-old man presenting with subacute progressive painless weakness in the right arm. Syphilitic amyotrophy is still an existing differential diagnosis of painless and progressive weakness. The authors explore potential obstacles in the diagnostic workup and finding of adequate therapy.

Adult↗
PubMed1992

Obstacles to effective case management with AIDS patients: the clinician's perspective.

A social work clinician filled the role of case manager with multiple functions of discharge planner, client advocate, counsellor and educator in her work with a young male AIDS patient and his family. Material from this case is used to illustrate seven problem areas identified as obstacles to effective case management: (1) The stigma of AIDS and homosexuality (2) Lack of adequate family support (3) Impact of AIDS dementia (4) Ethical dilemmas in discharge planning (5) Conflicts in the advocacy process (6) Lack of adequate resources and (7) Countertransference issues. Clinical observations are integrated with the existing social work literature which focuses on providing services to AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Children of Holocaust survivors: separation obstacles, attachments, and anxiety.

This article will discuss a research study conducted on the transmission of Holocaust trauma to children of survivors. The study examines and focuses on the effects Holocaust survivor parents have on their children focusing on three variables: separation obstacles, the ability to form substantial intimate relationships, and anxiety. Most Holocaust survivor parents perceive separation in a disapproving way and therefore it is often interpreted and handled differently in survivor families.

Adult↗
PubMed2003

The integration of gender in medical research and education-obstacles and possibilities from a Nordic perspective.

Research on women's issues in medicine was developed in the Nordic countries from the beginning of the 1980s. The theoretical developments led to a change of concepts from women's health to gender research, within which the structurally organised relations between men and women are analysed. Over the last decades, gender research has slowly been established in medical faculties, as a result of a strong political commitment for increased research and integration of gender issues in the university curriculum in Sweden. The government has made substantial investments in order to stimulate gender research and education in different disciplines, with special focus on medicine. Academic medicine has responded to this development with different strategies, including resistance and redefining concepts. Gender research has slowly become integrated into both research and teaching within Nordic academic medicine, although the pathway has not been easy. Gender research has had political support but there is a risk of backlash. Medical students' reactions to gender education can be compared with academic medicine's reactions towards gender research. Obstacles and possibilities are described in relation to teaching gender in schools of medicine. Most important is to recognise the risks for increased gender stereotypes and increased essentialism among the students, unless gender is taught from a theoretical perspective.

Biomedical Research↗