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PubMed2001

Evolving methodologies in bipolar disorder maintenance research.

BACKGROUND: During the development of a new treatment for bipolar disorder, maintenance studies are used to evaluate the ability of the putative mood stabilizer to prevent relapse and recurrence of further episodes. Comparisons with the early bipolar disorder maintenance studies indicate that the methodologies of recent trials have evolved substantially. AIMS: To review the methods used in the first- and second-generation maintenance studies, highlighting the differences of the various designs. METHOD: Literature review. RESULTS: Methods that have evolved the most include patient enrollment, randomisation schemes and the use of outcome measures and statistical analyses. In addition, regulatory and commercial issues have also influenced study design. CONCLUSION: There is little consensus on the methodology of bipolar disorder maintenance studies. As the integration of newer therapies into routine clinical practice is dependent on the evidence from controlled studies, it is essential that future maintenance trials in bipolar disorder achieve adequate methodological rigour without sacrificing overall feasibility.

Antimanic Agents↗
PubMed2002

How to undertake a clinically relevant systematic review in a rapidly evolving field. Magnetic resonance angiography.

OBJECTIVES: The aim was to determine which generations of the evolving technology of magnetic resonance angiography (MRA) are currently of clinical relevance in two clinical applications. Our purpose was to plan a systematic review that would be valuable both to purchasers driven by cost-effectiveness and to practicing clinicians. METHODS: Information was gathered from a search of major bibliographic databases, from a short questionnaire sent to 500 U.K. vascular radiologists and vascular surgeons, and from local clinical experts. We asked which of the MRA techniques were currently used and, assuming availability, what would be their technique of choice. RESULTS: There were 206 published articles that satisfied preliminary inclusion criteria: 69 discussed 2D time of flight (TOF); 47, 3D TOF; and 38, contrast-enhanced techniques. There were 162 questionnaires returned (60 radiologists, 102 surgeons). Of the total respondents, 77/162 (48%) used MRA in the assessment of carotid artery stenosis; 47/77 (61%) used 2D TOF; 32/77 (42%), 3D TOF; and 26/77 (34%), contrast-enhanced techniques. Thirty-five of 162 (22%) respondents used MRA in the assessment of peripheral vascular disease (PVD); 15/35 (43%) used 2D TOF, 4/35 (11%) used 3D TOF, and 22/35 (63%) used contrast-enhanced techniques. For those wishing to use MRA, contrast-enhanced techniques were the method of choice. CONCLUSIONS: The TOF methods that represent earlier generations of the technology remain clinically relevant, and will therefore be included in our systematic review. To ensure complete and relevant coverage in reviews of other evolving technologies, it would be advisable to obtain data for guidance in a similar way.

Humans↗
PubMed1975

Coronary arteriography in patients with impending and evolving myocardial infarction.

To determine whether characteristic pathologic alterations in coronary arteries are associated with impending and complicated evolving myocardial infarction, the angiographic and hemodynamic findings in 47 acute coronary patients were compared to those of 49 patients with chronic stable angina. Subtle differences in angiographic and hemodynamic alterations were found in these two groups of patients. These differences were more pronounced in patients with evolving myocardial infarction with less than--15 per cent lactate extraction. The risk of coronary arteriography was surprisingly low. Myocardial metabolic function studies demonstrating less than--15 per cent lactate extraction were considered an indication for emergency coronary arteriography in preparation for contemplated coronary bypass surgery.

Angina Pectoris↗
PubMedDate not supplied

Distant healing intention: definitions and evolving guidelines for laboratory studies.

This paper provides definitions and a discussion of evolving guidelines for conducting research on the effects of distant healing intention (DHI) on living systems in the laboratory. We consider the relevance of DHI laboratory research to applied healing, special theoretical challenges, and other considerations that distinguish DHI research from other domains of laboratory science. Two sample protocols for investigating DHI are provided, one involving the human autonomic nervous system as the "target" of distant intention, and the other involving cell cultures. In essence, DHI differs from other alternative healing modalities because it postulates that mental intention alone can affect living systems at a distance, unbounded by the usual constraints of both space and time. This postulate challenges scientific assumptions that often go unexamined, including the nature of causality, the distinction between subjective and objective states, and the efficacy of double-blind protocols in controlling for experimenters' intentions. Previous laboratory research in this domain suggests that DHI effects warrant serious study, but most scientists and funding agencies are unaware of the evidence or the relevant literature. By following these evolving guidelines, researchers' designs and their ultimate publications will conform more closely to the quality standards expected by scientific journals, and such publications will in turn attract the attention of a broader range of scientists. This seems especially important for alternative healing research in general and for distant healing in particular; both realms enjoy broad public support but have largely eluded serious attention by mainstream science.

Brain↗
PubMed2004

Evolving techniques for monitoring clotting in plasma and whole blood samples.

New models of hemostatic function emphasize the importance of clotting factor interactions with cells and highlight the central event of thrombin production. As the coagulation cascade has evolved into a scheme of overlapping phases of initiation, amplification and propagation, the relevance of plasma based coagulation assays are being brought into question. Since platelets are critical to both amplification and propagation of the thrombin signal, assays performed in the absence of platelets would appear to completely miss these events. The lack of sensitivity to platelet influences may explain the inability of the prothrombin time (PT) and the partial thromboplastin time (PTT) to detect/reflect the therapeutic and clinical effects of agents such as recombinant FVIIa. This article reviews several evolving technologies for measuring thrombin generation and hemostatic function in samples of plasma and whole blood. Such assays may better reflect global hemostasis and hold potential for detecting hypo- and hyper-hemostatic states as well as monitoring both hemostatic and anticoagulant agents.

Blood Coagulation Disorders↗
PubMed2005

[Three steps for amplifying quick evolving region of DNA.].

A common problem in research of molecular evolution is difficult to efficiently amplify quick evolving target sequence of genes in different species or genus using specific primers, thus making experimental process and final analysis of total results delayed. Although using nested or semi-nested PCR can prominently increase PCR specificity, it really cannot efficiently amplify quick evolving region of DNA in our research of gene Fak56D. In this research, we need PCR products corresponding to gene Fak56D of different species of Drosophila melanogaster or other genus of Drosophila . For the high evolutionary rate,most materials did not produce qualified PCR products. To solve this problem, we initially used a combination method of three steps, i.e. semi-nested PCR taken together with orientational gel extraction, which satisfactorily met the demands of next cloning and sequencing steps.

Animals↗
PubMed2005

The evolution of strategy variation: will an ESS evolve?

Evolutionarily stable strategy (ESS) models are widely viewed as predicting the strategy of an individual that when monomorphic or nearly so prevents a mutant with any other strategy from entering the population. In fact, the prediction of some of these models is ambiguous when the predicted strategy is "mixed", as in the case of a sex ratio, which may be regarded as a mixture of the subtraits "produce a daughter" and "produce a son." Some models predict only that such a mixture be manifested by the population as a whole, that is, as an "evolutionarily stable state"; consequently, strategy monomorphism or polymorphism is consistent with the prediction. The hawk-dove game and the sex-ratio game in a panmictic population are models that make such a "degenerate" prediction. We show here that the incorporation of population finiteness into degenerate models has effects for and against the evolution of a monomorphism (an ESS) that are of equal order in the population size, so that no one effect can be said to predominate. Therefore, we used Monte Carlo simulations to determine the probability that a finite population evolves to an ESS as opposed to a polymorphism. We show that the probability that an ESS will evolve is generally much less than has been reported and that this probability depends on the population size, the type of competition among individuals, and the number of and distribution of strategies in the initial population. We also demonstrate how the strength of natural selection on strategies can increase as population size decreases. This inverse dependency underscores the incorrectness of Fisher's and Wright's assumption that there is just one qualitative relationship between population size and the intensity of natural selection.

Biological Evolution↗
PubMed2005

The coevolutionary dynamics of antagonistic interactions mediated by quantitative traits with evolving variances.

Quantitative traits frequently mediate coevolutionary interactions between predator and prey or parasite and host. Previous efforts to understand and predict the coevolutionary dynamics of these interactions have generally assumed that standing genetic variation is fixed or absent altogether. We develop a genetically explicit model of coevolution that bridges the gap between these approaches by allowing genetic variation itself to evolve. Analysis of this model shows that the evolution of genetic variance has important consequences for the dynamics and outcome of coevolution. Of particular importance is our demonstration that coevolutionary cycles can emerge in the absence of stabilizing selection, an outcome not possible in previous models of coevolution mediated by quantitative traits. Whether coevolutionary cycles evolve depends upon the strength of selection, the number of loci, and the rate of mutation in each of the interacting species. Our results also generate novel predictions for the expected sign and magnitude of linkage disequilibria in each species.

Biological Evolution↗
PubMed2004

Acromegaly - evolving strategies.

Growth hormone (GH)-cell adenomas are benign pituitary tumors which present with chronic high GH output. Hereditary GH-cell adenomas are rare and include MEN I, McCune Albright Syndrome, Carney complex and familial acromegaly. Most of the tumors causing acromegaly are sporadic. Acromegaly is a disfiguring and disabling disease and, if untreated, life expectancy is reduced by a decade. Elevated GH levels, hypertension and heart disease are major negative survival determinants in these patients. Current treatments for acromegaly attempt to control the disease by reducing growth hormone secretion from the tumor either by surgery, radiotherapy or medical therapy. The choice of therapy depends on age, general health, the severity and complications of the disease and dangers associated with each treatment. Assessment of disease activity in patients with acromegaly following treatment is a problem because no sensitive clinical parameters are available and there is no well-defined clinical endpoint that defines cure. Cure in acromegaly has been defined therefore as normalization of biochemical parameters. A consensus publication recommended biochemical cure be considered as nadir GH of less than 1 microm g/L after OGTT and a normal circulating IGF-I. In optimizing the control of acromegaly new therapeutic strategies are evolving (growth hormone receptor antagonist - pegvisomant, potent dopamine agonists, universal somatostatin receptor ligands, chimeric molecules). The aim of the evolving therapeutic strategies is to produce a normal life expectancy in patients with acromegaly.

Acromegaly↗
PubMed2006

[Research on EEG classification with evolving cascade neural networks].

To correctly classify EEG with different mental tasks, a new learning algorithm for Evolving Cascade Neural Networks (ECNNs) is described to avoid over-fitting of a neural network due to noise and redundant features. The learning algorithm calculates the value of a fitness function on validate set and accordingly updates the connection weights on training set. The learning algorithm uses the regularity criterion for selecting the neurons with relevant connection. If the value Cr calculated for the rth neuron is less than the value Cr-1 calculated for the previous (r-1) neuron, the features that feed the rth neuron are relevant, else they are irrelevant. An ECNN starts to learn with one input node and then, adding new inputs as well as new hidden neurons, evolves it. The trained ECNN has a nearly minimal number of input and hidden neurons as well as connections. The algorithm is applied to classify EEG with two mental tasks. The trained ECNN has correctly classified 83.1% of the testing segments. It shows a better result, compared with a standard BP network.

Algorithms↗
PubMed1990

The evolving clinical chart. How it reflects and influences psychiatric and medical practice and the quality of care.

The clinical chart constitutes an evolving patient care document. This article compares charts from the turn of the century with those of today. It has changed from a simple user-friendly personal note record to a major medical-legal documentation system. With this evolution have come shifts in clinicians' attitudes toward the chart, a more active role in influencing care for the record, a much more public position of it, and a more homogenized record. It concludes with methods for the practitioners to incorporate the evolving chart into their work so as to further improve their documentation and care.

Confidentiality↗
PubMedDate not supplied

Evolving conceptualizations of cocaine dependence.

Cocaine was considered incapable of producing dependence in 1980 but was proclaimed the "drug of greatest national public health concern" by 1984. Clinical consensus in 1980 held that cocaine did not produce a withdrawal syndrome, but recent clinical investigations demonstrate that cocaine produces unique abuse and withdrawal patterns that differ from other major abused drugs. Evolving pre-clinical research over the past two decades now suggests that chronic cocaine abuse produces neurophysiological alterations in specific central nervous system systems that regulate the capacity to experience pleasure. These evolving clinical and pre-clinical constructs have led to applications of promising experimental pharmacological treatments for cocaine abuse.

Affective Symptoms↗
PubMed1988

Urgent surgical reperfusion in acute evolving myocardial infarction. A randomized controlled study.

To assess the benefit of immediate surgical reperfusion over conventional medical treatment during the first acute evolving transmural myocardial infarction, 68 patients presenting within 4 hours of onset of chest pain were randomized into a medical group and a surgical group. Both groups were comparable for age, sex, coronary risk factors, location of infarct, and coronary anatomy. Radionuclide global ejection fraction at 48 hours after admission was 45 +/- 15% for the medical group versus 50 +/- 15% for the surgical group; at 3 months, ejection fraction values were 51 +/- 13% and 51 +/- 13%, respectively (p = NS). The average radionuclide wall-motion scores (normal, 3) at 3 months were 2 +/- 0.6 for the medical group and 2 +/- 0.7 for the surgical group. There were three (8.8%) early and four (11.7%) late deaths in the medical group and only one (2.9%) early death in the surgical group. Urgent surgical reperfusion in acute evolving myocardial infarction is a safe and effective procedure that appears to reduce early and late mortality but does not appear to improve left ventricular function.

Clinical Trials as Topic↗
PubMed1988

Congenital hepatic fibrosis: evolving morphology.

A clinicopathologic study of congenital hepatic fibrosis in 21 patients confirms a strong association with autosomal recessive renal polycystic disease. The liver specimens were subclassified into two groups according to the severity of fibrosis, showing typical hepatic abnormalities in young infants (mean age 0.3 years) and increased hepatic fibrosis in older patients (mean age 19.6 yr) (p less than 0.02). Apparent progression to perilobular fibrosis with parenchymal nodularity occasionally resembled cirrhosis when the nodules had a regenerative appearance because of rounded contours and inapparent central veins. Progression of fibrosis was observed in second biopsy specimens from 2 cases, but not in that of a 3rd, suggesting that factors other than the heritable disorder itself may be responsible for evolving morphology. Identifiable factors that may have contributed to increased fibrosis included localized intrahepatic biliary obstruction and biliary sepsis with suppuration. A factor possibly contributing to the pathogenesis of biliary sepsis was intrahepatic biliary ectasia, i.e., Caroli's disease, which appears to be one morphologic expression of CHF. This study shows that the hepatic abnormality evolves over time and that it may be altered by secondary complications.

Bile Duct Diseases↗
PubMed1987

[Emergency myocardial revascularization in acute evolving myocardial infarct].

Immediate coronary artery bypass for acute evolving myocardial infarction could be the elective therapy if provided on useful time, because myocardial salvage can be achieved by early reperfusion. Thirty eight patients had emergency coronary artery by-pass graft for acute evolving myocardial infarction during the early phase: 35 were male, the mean age was 51 years (34 to 74). The mean interval between the onset of symptoms and surgery in this series of patients was two hours and a half. This interval seems to be also the time limit in our experience to get a partial or complete recovery of ischemic area. Four patients died in hospital, but they were in severe cardiogenic shock before emergency surgery. Twenty nine cases were free of symptoms at a mean follow-up of 18 months (6 to 36) and two suffered for residual angina. Three patients died after discharge few months later: two during redo emergency vein grafts operations, one in deep left ventricular failure, while he was waiting for heart transplant. All these patients operated on as emergency developed acute myocardial infarction during their stay in hospital waiting for catheter study, surgical operation or during percutaneous transluminal coronary angioplasty. Saphenous vein grafts, were used in twenty nine patients, left internal mammary artery in nine cases, single in four and associated to saphenous vein in five, with an average number of anastomoses of 2.6 (1 to 6) for patient. ECG was found to be normal in 76% of the patients operated on within two hours and a half from the beginning of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Time constraints in the emergency coronary bypass surgery for acute evolving myocardial infarction.

Fourty four patients underwent emergency coronary grafting for evolving myocardial infarction. All patients but one had undergone coronary angiography before the new infarction, 50% were in cardiogenic shock or under cardiopulmonary resuscitation. The mean time interval between the onset symptoms and opening of the bypass to the threatened area was 171 minutes. The operative mortality was 6.8%. At 30 months after surgery, the cardiac actuarial survival was 93.2%, the angina free group 94.2% of the operative survivors. Infarct size and regional ejection fraction of these patients at late follow-up were compared to those of controls treated conventionally for acute infarction. The thallium defects were smaller and the regional ejection fraction of the involved segment was higher after early surgery (less than 3 hours ischemia) than in controls. In the late surgery group the thallium defects and the regional ejection fractions were similar. Ultrastructural studies on biopsy samples taken from the center of the threatened area show reversible changes in the early surgery group but irreversible mitochondrial damage and cell membrane rupture in the late surgery group. Biochemical analysis of similar cardiac biopsies shows recovery after one hour empty beating reperfusion but only in the early surgery group. Our results suggest that coronary surgery can be beneficial to the patient with an evolving myocardial infarction, if the clinical situation does not permit intracoronary thrombolysis. However, one hour reperfusion of the empty beating heart before weaning off bypass is essential. The time constraints for both emergency surgery or thrombolysis are similar.

Adult↗
PubMed1987

Emergency coronary bypass grafting for evolving myocardial infarction. Effects on infarct size and left ventricular function.

Emergency aorta-coronary bypass grafting was performed early in the course of evolving myocardial infarction in 48 patients. The time interval between the onset of symptoms and reperfusion was 169 +/- 80 minutes. Quantitative assessment of postoperative thallium 201 myocardial scans in 19 patients revealed a significant salvage of myocardium after surgical reperfusion: The size of the residual infarction was less than 50% of that in a matched, medically treated, prospective control group (n = 39) (p less than 0.05). Postoperative equilibrium-gated radionuclide blood pool studies (technetium 99m) showed an enhanced recovery of regional and global ejection fraction after operation as compared to after medical treatment (p less than 0.05). Ultrastructural evaluation of biopsy specimens obtained during the operation delineated subendocardial necrosis in the majority of cases (72%), but subepicardial necrosis was found in only 6% of instances. Q-wave abnormalities were observed on the postoperative electrocardiogram in 50% of cases. Operative mortality was 0% in low-risk patients (i.e., hemodynamically stable condition, n = 26) and 18% in high-risk patients (i.e., cardiogenic shock including total electromechanical dysfunction, n = 22). Survival rate at 18 months was 92% +/- 4%, and 95% +/- 4% of the survivors were event free. It is concluded that early surgical reperfusion of evolving myocardial infarction limits infarct size significantly, enhances functional recovery, and may be a lifesaving operation in patients having cardiogenic shock associated with unsuccessful resuscitation.

Actuarial Analysis↗
PubMed1981

Surgical therapy for evolving myocardial infarction: Results in 138 patients.

One hundred thirty-eight selected patients underwent emergency coronary artery revascularization as the treatment for early evolving myocardial infarction. Low early and late (3.6 and 2.9%) mortality and morbidity up to 54 months, with favorable post surgical hemodynamic improvement demonstrates the operability with beneficial results in selected patients with early evolving myocardial infarction.

Adult↗