PubMed HealthSearch

SEARCH · PubMed Health

Results for “Complex intervention”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 91 records · Page 5Linked to original sources

Vector population responses to control interventions.

In 1981, Kenyan authorities attempted eradication of tsetse (Glossina pallidipes) from the Lambwe valley, by sequential aerial spraying of endosulfan. Fly populations were reduced by over 99.9% in the main habitats, but recovered to their original levels within one year. In 1986, an Argentine research team attempted local elimination of domestic Triatominae (Triatoma infestans) in an area of Santiago del Estero. House infestation rates were reduced to an apparent zero, but recovered to pre-control levels in two years. In Sri Lanka, a combination of mosquito control with active case detection and treatment reduced malaria incidence to just 17 cases in 1964. Interruption of the programme then saw case incidence return to over 500,000 by 1969. These three examples-from African trypanosomiasis, South American Chagas disease and malaria-all illustrate the same process. Vector populations, infestation rates, and rates of disease transmission, can be reduced. The real problem is not in achieving the initial reduction, but in subsequently either driving the disease to extinction or maintaining it below acceptable levels. And this problem takes us beyond the simple analysis of interventions, into the complex realms of population behaviour set in its political, social and economic context. It seems that we have been too rarely concerned to plan and implement the long term surveillance and selective interventions that are required to translate initial gains into real success. In biological terms, we tend to ignore the complexity and robustness of vector populations and disease transmission cycles, especially their varied capacity to recover from interference. Moreover, in socio-political terms, a reduced problem-even one representing potential for future catastrophe-tends to claim less priority than present problems, even though premature redeployment of resources may abnegate gains already achieved. The problem is strongly compounded by methods of economic analysis where the benefits of avoiding future problems are strongly discounted in favour of short-term temporary gains. This paper seeks to open discussion on these long-term planning issues.

Animals

Poverty and early childhood parenting: toward a framework for intervention.

The relationship between poverty and child rearing has been a persistent source of social concern in the United States. Drawing on available literature, this paper seeks to establish a conceptual approach to the interaction of these two complex variables. Appropriate interventions and strategies for their implementation are considered.

Child

Management of ventricular arrhythmias.

Left ventricular dysfunction and complex VPCs are independent risk factors for subsequent cardiac death in patients with ischemic or nonischemic heart disease. The use of antiarrhythmic drugs during acute myocardial infarction is discussed. Patients with complex VPCs associated with heart disease should be treated with antiarrhythmic drugs. Drug efficacy should be evaluated by a 24-hour ambulatory ECG recording and by a treadmill exercise stress test. Blood drug levels should be measured at appropriate times. Maintenance doses of the various antiarrhythmic drugs are listed. Electrophysiologic testing with induction of ventricular tachycardia by extrastimulation may predict the clinical efficacy of the antiarrhythmic drug or combination of drugs needed for the long-term treatment of ventricular tachyarrhythmias. Electrophysiologic testing must be used for selecting antiarrhythmic drugs in patients who have experienced sustained ventricular tachycardia or ventricular fibrillation but who are free of VPCs during ambulatory ECG monitoring and exercise stress testing. If patients have life-threatening ventricular tachycardia or fibrillation resistant to antiarrhythmic drugs, surgical intervention is indicated. Complex VPCs in asymptomatic patients without heart disease should not be treated with antiarrhythmic drugs.

Anti-Arrhythmia Agents

[Australia antigen in rheumatoid arthritis].

Australian antigen (Au Ag) was first described by Blumberg in the serum of an Australian aborigen. Its main clinical significance is based on the fact of its association with the presence of hepatitis B (Okochi, Nurakami, 1968; Prince, 1968) (9). Almeida (1969) outlines the intervention of immune complexes on the production of the referred illness. Later works show the importance of the type of immunologic response created by Au Ag (2). Alpert et al. (1) (1970) state the possibility that immune complexes developed by Au Ag and anti Au Ag antibodies may produce in patients with hepatitis B other allied manifestations including arthritis. On the basis of similar immunopathological findings (illnesses including immunocomplexes on their production), Au Ag investigation in rheumatoid arthritis (RA) has been the object of several works, whose results reveal certain discrepancies. We have investigated the presence of Au Ag on 70 patients whose diagnostic was RA "classical (according to the judgement of the American Rheumatism Association). We used immunoelectrophoresis (counter immunoelectrophoresis-CIEP-) and radioimmunoassay (RIA) techniques. We prepared individual records including clinical, epidemic, biochemical and personal data. Au Ag investigation both through different techniques gave negative results in 70 cases, of which only four referred a possible previous hepatitis B clinic history, not showing during the investigation suggestive clinical data of hepatitis or biochemical alterations. Panus et al. (1970) (5), Desche-Labarte et al. (1972), Trempo (1972), Burrel (1973) (6), Serré et al. (1973) (8), obtained negative results in the matter, with similar or lower casuistics than ours. Notwithstanding Roqués et al. (1975) (7), in 300 cases of RA showed the presence of Au Ag in a significant number of cases (5%) as compared to Au Ag incidence in the French population (estimated in about 0.22%) (6). However, Roqués did not find in their Au Ag positive cases any evidence which enables to think that this antigen has played an important role on the origin and development of the rheumatic illness. These important discrepancies may be due to different reasons: a) Use of different techniques for Au Ag detection. b) The transitory character of the presence of Au Ag in the serum. c) Important differences in the antigen geographic distribution. d) Previous hepatitis B. There are som other factors which have attained importance recently, as a consequence of the broad epidemiological studies carried out. So, Au Ag increased incidence has been found--statistically significant--on groups of persons who have been submitted to several surgical interventions and/or have needed repeated hospitalizations or reiterated blood transfusions (6). These three conditions--especially the first two--are accomplished in an illness with chronic and invalidating characteristics as RA...

Arthritis, Rheumatoid

Current techniques for infrainguinal arterial reconstruction.

Infrainguinal reconstruction for peripheral vascular occlusive disease comprises an increasingly complex array of interventions which provide unparalleled options for the salvage of threatened limbs. Conventional autogenous saphenous vein bypass remains the most durable revascularization with anticipated graft patency rates approaching 80 percent after five years and excellent long term limb salvage. These excellent results are equally applicable to vein grafts carried to infrapopliteal and even inframalleolar levels, possibly reflecting increased utilization of the in situ method. Although 20 per cent of grafts fail within five years, secondary intervention results in sustained limb salvage in the majority of patients. In the absence of autogenous vein, however, prosthetic material performs poorly such that new interventions consisting of percutaneous transluminal angioplasty, rotary atherectomy devices and laser systems are under aggressive development. Although initial results with these devices are encouraging, long term patency rates remain poor largely due to restenosis. Further progress seems to depend primarily on an increased understanding of the natural healing response of the injured artery.

Angioplasty, Laser

Mismatch of coronary risk and treatment intensity under the National Cholesterol Education Program guidelines.

OBJECTIVE: To assess the match between multifactorial risk of coronary heart disease (CHD) and treatment intensity under the National Cholesterol Education Program (NCEP) guidelines for primary prevention of CHD. METHODS: The multiple logistic regression equation from the Framingham Study was used to derive predicted risks for development of CHD over eight years of follow-up for different age-gender groupings, with serum total cholesterol (TC) values chosen in light of the NCEP cutoff points for both TC and low-density-lipoprotein cholesterol levels. Additional risk factors--hypertension, glucose intolerance, and smoking--were considered in combination for each of these values. RESULTS: Controlling for the effects of age and gender, there is little difference in the ranges of absolute CHD risks for persons who would receive interventions of differing intensities (i.e., general dietary advice, dietary treatment, or drug therapy). Those who are candidates for drug treatment because of serum lipids alone are often at low levels of risk for the development of CHD when compared with those of the same age with lower TC values who have other risk factors. Discrepancies in CHD risk are wider still when age is also allowed to vary. Furthermore, in every age grouping, women with high TC levels (e.g., 6.9 mmol/L) and two other risk factors are eligible for drug treatment but have a CHD risk that is no higher, and often much lower, than that of males with one other risk factor and TC levels of 4.8 mmol/L or 5.7 mmol/L who are candidates for dietary advice or dietary therapy, respectively. CONCLUSIONS: Inconsistencies exist in the NCEP guidelines such that persons at low risk for the development of CHD are offered more intensive interventions than are other who actually are at much higher risks, and vice versa. Women in particular tend to be overtreated, relative to men. These findings point out the difficulties of promulgating guidelines that will appropriately match risk to preventive interventions in a complex multifactorial disease.

Adult

Automated real-time data acquisition and analysis of cardiorespiratory function.

Microcomputer generation of an automated record without complexity or operator intervention is desirable in many circumstances. We developed a microcomputer system specifically designed for simplified automated collection of cardiorespiratory data in research and clinical environments. We tested the system during possible extreme clinical conditions by comparison with a patient simulator. Ranges used were heart rate of 35-182 beats per minute, systemic blood pressures of 65-147 mmHg and venous blood pressures of 14-37 mmHg, all with superimposed respiratory variation of 0-24 mmHg. We also tested multiple electrocardiographic dysrhythmias. The results showed that there were no clinically relevant differences in vascular pressures, heart rate, and other variables between computer processed and simulator values. Manually and computer recorded physiological variables were compared to simulator values and the results show that computer values were more accurate. The system was used routinely in 21 animal research experiments over a 4 month period employing a total of 270 collection periods. The file system integrity was tested and found to be satisfactory, even during power failures. Unlike other data collection systems this one (1) requires little or no operator intervention and training, (2) has been rigorously tested for accuracy using a wide variety of extreme patient conditions, (3) has had computer derived values measured against a standardized reference, (4) is reliable against external sources of computer failure, and (5) has screen and printout presentations with quick and easily understandable formats.

Computer Systems

The intracellular equilibrium thermodynamic and steady-state concentrations of metabolites.

A new model for the organization and flow of metabolites through a metabolic pathway is presented. The model is based on four major findings. (1) The intracellular concentrations of enzyme sites exceed the concentrations of intermediary metabolites that bind specifically to these sites. (2) The concentration of the excessive enzyme sites in the cell is sufficiently high so that nearly all the cellular intermediary metabolites are enzyme-bound. (3) Enzyme conformations are perturbed by the interactions with substrates and products; the conformations of enzyme-substrate and enzyme-product complexes are different. (4) Two enzymes, catalyzing reactions that are sequential in a metabolic pathway, transfer the common metabolite back and forth via an enzyme-enzyme complex without the intervention of the solvent environment. The model proposes that the enzyme-enzyme recognition is ligand-induced. Conversion of E2S and E2P results in the loss of recognition of E2 by E1 and the concomitant recognition of E2 by E3. This model substantially alters existent views of the bioenergetics and the kinetics of intracellular metabolism. The rates of direct transfer of metabolite from enzyme to enzyme are comparable to the rates of interconversion between substrate and product within an individual enzyme. Consequently, intermediary metabolites are nearly equipartitioned among their high-affinity enzyme sites within a metabolic pathway. Metabolic flux involves the direct transfer of metabolite from enzyme to enzyme via a set of low and nearly equal energy barriers.

Biological Evolution

High-Fat Diet and a High Amyloid Load Interact to Induce PKC-α Dependent Synaptic Insulin Resistance.

A plethora of studies suggest that a high-fat diet in combination with a high amyloid load causes synaptic insulin resistance and is a risk factor for Alzheimer's disease. Our understanding of the underlying mechanisms is still fragmented. To gain new insights, we conducted integrated proteomic and phosphoproteomic profiling of hippocampal synaptosomes from WT and a transgenic mouse line with a high amyloid load (heterozygous TBA2.1 mice) that show no overt signs of neurodegeneration and dementia. Mice were fed with a regular or high-fat diet. Data-independent acquisition quantified over 5400 proteins, revealing a stable synaptic proteome across conditions. However, the combination of high amyloid load and high-fat diet triggered coordinated remodeling of lipid metabolism pathways, particularly mitochondrial and peroxisomal fatty acid catabolism. Phosphoproteomic analysis showed pronounced activation of lipid- and stress-responsive kinases, including protein kinase C-α, along with increased inhibitory phosphorylation of insulin receptor substrates (IRS1/2). In vitro experiments indicate that blocking protein kinase C-α indeed prevents synaptic insulin resistance in primary neurons. The findings suggest that this proteomic workflow, combined with kinase pathway analysis, can reveal nodal points for interventions in a complex disease state with a trajectory to Alzheimer's disease.

Animals

[Pharmacological and molecular aspects of the regulation of eating behavior. With special reference to the role of catecholamines and effects of amphetamine].

Among the numerous endogenous substances involved in the regulation of feeding behaviours, the catecholamines are in the front rank. The numerous studies devoted to this aspect of catecholamines emphasize the importance and complexity of their intervention. Depending on the cerebral structures on which they act and on whether noradrenaline or dopamine are concerned, orexigenic or anorexigenic effects have been described. Alpha-2 and beta adrenergic receptors as well as D1 and D2 dopaminergic receptors participate in these effects. Amphetamine, which is an indirect catecholaminergic agonist, mobilizes neuronal catecholamines and fosters their various effects. Moreover, it exercises direct effects by its association with sites borne by glycaemia-sensitive neurons. This target seems to be common to a wide variety of anorectic agents. They are thought to reproduce on this hypothalamic "glucostat" the effect of a high blood glucose level, thus triggering off signals of satiety. In this unifying hypothesis, the diverse pharmacological profiles these agents are known to possess would result from associated properties.

Amphetamine

Trust, control strategies and allocation of function in human-machine systems.

As automated controllers supplant human intervention in controlling complex systems, the operators' role often changes from that of an active controller to that of a supervisory controller. Acting as supervisors, operators can choose between automatic and manual control. Improperly allocating function between automatic and manual control can have negative consequences for the performance of a system. Previous research suggests that the decision to perform the job manually or automatically depends, in part, upon the trust the operators invest in the automatic controllers. This paper reports an experiment to characterize the changes in operators' trust during an interaction with a semi-automatic pasteurization plant, and investigates the relationship between changes in operators' control strategies and trust. A regression model identifies the causes of changes in trust, and a 'trust transfer function' is developed using time series analysis to describe the dynamics of trust. Based on a detailed analysis of operators' strategies in response to system faults we suggest a model for the choice between manual and automatic control, based on trust in automatic controllers and self-confidence in the ability to control the system manually.

Adult

Optical and nuclear magnetic resonance studies of hypoxia in human tissue and tumors.

Correlations of energy state with response to therapy are more difficult to analyze because of the large effect of tumor clearing and oxygenation upon the tumor energy state as detected by PMRS alone. The combination of time-resolved hemoglobinometry using picosecond laser technology and localized PMRS seems appropriate to unravel the complexities of therapeutic intervention, tumor energetics, and oxygenation.

Energy Metabolism

Development of infants with disabilities and their families: implications for theory and service delivery.

This Monograph presents the results of a nonexperimental, longitudinal investigation of developmental change in 190 infants and their families after 1 year of early intervention services. The Early Intervention Collaborative Study (EICS), conducted in association with 29 community-based programs in Massachusetts and New Hampshire, was designed to assess correlates of adaptation in young children with disabilities and their families over time, to inform social policy by analyzing the influences of family ecology and formal services on child and family outcomes, and to generate conceptual models to guide further investigation. The study sample (mean age at entry = 10.6 months) includes 54 children with Down syndrome, 77 with motor impairment, and 59 with developmental delays of uncertain etiology. Data were collected during two home visits (within 6 weeks of program entry and 12 months later) and included formal child assessments, observations of mother-child interaction, maternal interviews, and questionnaires completed independently by both parents as well as monthly service data collected from service providers. Child and family functioning varied considerably. Developmental change in the children (psychomotor abilities, adaptive behavior, spontaneous play, and child-mother interaction skills) was influenced to some extent by gestational age and health characteristics, but the strongest predictor of change was the relative severity of the child's psychomotor impairment at study entry. Families demonstrated generally positive and stable adaptation (in terms of the effect of rearing a child with disabilities on the family, parenting stress, and social support), despite persistent challenges with respect to mother-child interaction and differences in reported stress between mothers and fathers. Documentation of services revealed that early intervention is a complex and multidimensional experience that spans multiple public and private systems. Vulnerable and resilient subgroups within the sample were identified, and different correlates of adaptive change were demonstrated. Results of data analyses suggest new perspectives on the study of early childhood disability. The implications of the findings for developmental theory and social policy are discussed.

Adaptation, Psychological

Unusual presentations of aortoiliac aneurysms.

Unusual presentations of aortoiliac aneurysms may be the reason for a delay in diagnosis of potentially life-threatening conditions. Five such unusual clinical pictures are presented and discussed. The aneurysms were falsely diagnosed as malignant disease, renal colic, sciatic syndrome, intra-abdominal bleeding of unknown origin, and psoas muscle abscess. The medical staff was misled by the atypical complaints, signs and symptoms, which resulted in a dangerous delay in diagnosis. The use of currently available ultrasonography and CAT scans, which enables early diagnosis, depends on the alertness of clinicians when they confront an atypical clinical picture that may be the first clue of a noninnocent aneurysm of the aortoiliac complex. Early surgical intervention before dissection, rupture or fistulization occur ensures a positive outcome and avoids emergency procedures with their attendant high operative mortality and postoperative morbidity.

Aged

Psychosocial issues of nutritional support. A multidisciplinary interpretation.

In many cases, initiation of specialized nutritional support is a final attempt at medically managing illness for which other treatments have failed. Patients may have suffered for months or even years with their underlying diseases and are usually aware that poor response to nutritional support and concurrent therapies may lead to surgical intervention or more complex treatment. In some cases, there may be few alternatives left to pursue. For such patients, this paints a very stressful picture. If we as caregivers are empathetic to each patient's situation, we are better able to offer the support that these patients need. Health care professionals must keep patients informed of treatment plans and encourage participation in the planning process--during hospitalization, through the discharge phase, and after hospitalization. We need to pay close attention to those needs, whether nutritional support is short-term during hospitalization, prolonged, or permanent. The health care environment is demanding greater proficiency in cost containment and quality assurance in the delivery of care. Complex patient cases are becoming more difficult to manage as time constraints and resources become more restrictive. The ingenuity and imagination of health care providers trying to find ways to continue providing high-quality and safe care to patients are being tested daily. These worthwhile goals can be met only through cooperation, communication, and support among all levels and disciplines involved with the delivery of care. Feelings of helplessness, dependence, and loss of control can be diminished if health care providers maintain optimistic, confident attitudes, offer positive reinforcement for patients successes, and try to restore hope during this stressful period in patients' lives.

Adult

Nonsurgical management of pain secondary to peripheral nerve injuries.

Physicians and surgeons dealing with peripheral nerve injuries have long been plagued by the chronic intractable pain which often follows these injuries. Early recognition of the associated problems and prompt intervention by a multidisciplinary team approach to the pain is essential. Although the techniques reviewed here were presented as separate choices, the treatment of the patient should employ a combined approach of good surgical repair, positive encouragement, non-addicting medications, appropriately timed nerve blocks, aggressive physical and occupational therapy, and electrical stimulation techniques as the patient's physical recovery permits. The importance of early psychological assessment and intervention in this complex phenomenon cannot be overemphasized. Together these techniques may succeed in reducing the morbidity associated with peripheral nerve injuries.

Anti-Inflammatory Agents, Non-Steroidal

Gait changes in adult onset hemiplegia.

Multiple parameters of gait were evaluated in 50 adult acquired hemiplegic patients and 30 control patients with no history of gait abnormality and no deviation from normal gait by observational analysis. Findings in the hemiplegic group include: 1) increase in the proportion of the gait cycle spent in stance and double-limb support phases in both the normal and affected limb; 2) consistent deviation from normal gait pattern by observation and objective pattern analysis; 3) abnormal phasic activity of specific muscles and muscle groups in the affected limb; and 4) a consistent electrogoniometric deviation from normal joint ankle progression in the affected hip, knee and ankle. These data lend credence to the hypothesis that gait deviation in adult acquired hemiplegia follows a consistent pattern varying with the severity of central nervous system involvement. These data also provide a baseline from which to measure therapeutic intervention in this complex patient population.

Adult

Nursing care of the elderly patient with cancer. The critical blend of science and art--back to basics.

In summary, the nursing care of the elderly patient with cancer incorporates very complex assessments and interventions. Fundamental to the delivery of good care is meeting the basic biological, psychological and social needs of each patient while providing oncologic care in the treatment of their disease and its symptoms. Nursing the elderly requires intelligence, patience, attention to detail, love, gentleness and, above all, hard work. Although we may not always be able to keep up with the science of cancer care, we must always keep up with the art.

Aged