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At least 523 records · Page 29Linked to original sources
PubMed2006

The dynamism of cutaneous lupus erythematosus: mild discoid lupus erythematosus evolving into SLE with SCLE and treatment-resistant lupus panniculitis.

We present a 47-year-old Caucasian female who initially presented with mild discoid lupus erythematosus that evolved into systemic lupus erythematosus with subacute cutaneous LE and treatment-recalcitrant lupus panniculitis. Conventional therapy with antimalarials, systemic steroids, azathioprine, cyclophosphamide, methotrexate, and pulse doses of methylprednisolone did not control the course of the disease. Cyclosporin-A treatment led to clinical improvement and maintained remission.

Antimalarials↗
PubMed2005

Brief report: pervasive developmental disorder can evolve into ADHD: case illustrations.

Despite prominent attentional symptoms in Pervasive Developmental Disorders (PDD) the relationship between PDD and Attention Deficit Hyperactivity Disorder (ADHD) has received little direct examination. In addition, outcome studies of children with PDD often focus on language, educational placement, or adaptive skills, but seldom on loss of the PDD diagnosis or change to another clinical syndrome. We present three cases in detail, and tabular data on eight more, that illustrate a clinical presentation in which prototypical cases of PDD evolve into clear-cut cases of ADHD from early to middle childhood.

Attention Deficit Disorder with Hyperactivity↗
PubMed2005

Studies on photosynthetic oxygen-evolving complex by means of Fourier transform infrared spectroscopy: calcium and chloride cofactors.

Structural roles of functional Ca2+ and Cl- ions in photosynthetic oxygen-evolving complexes (OEC) were studied using low- (640-350 cm-1) and mid- (1800-1200 cm-1) frequency S2/S1 Fourier transform infrared (FTIR) difference spectroscopy. Studies using highly active Photosystem (PS) II core particles from spinach enabled the detection of subtle spectral changes. Ca2+-depleted and Ca2+-reconstituted particles produced very similar mid- and low-frequency spectra. The mid-frequency spectrum was not affected by reconstitution with 44Ca isotope. In contrast, Sr2+-substituted particles showed unique spectral changes in the low-frequency Mn-O-Mn mode at 606 cm-1 as well as in the mid-frequency carboxylate stretching modes. The mid-frequency spectrum of Cl- -depleted OEC exhibited marked changes in the carboxylate stretching modes and the suppression of protein modes compared with that of Cl- -reconstituted OEC. However, Cl- -depletion did not exert significant effects on the low-frequency spectrum.

Calcium↗
PubMed2006

Damage to the oxygen-evolving complex by superoxide anion, hydrogen peroxide, and hydroxyl radical in photoinhibition of photosystem II.

Under strong illumination of a photosystem II (PSII) membrane, endogenous superoxide anion, hydrogen peroxide, and hydroxyl radical were successively produced. These compounds then cooperatively resulted in a release of manganese from the oxygen-evolving complex (OEC) and an inhibition of oxygen evolution activity. The OEC inactivation was initiated by an acceptor-side generated superoxide anion, and hydrogen peroxide was most probably responsible for the transportation of reactive oxygen species (ROS) across the PSII membrane from the acceptor-side to the donor-side. Besides ROS being generated in the acceptor-side induced manganese loss; there may also be a ROS-independent manganese loss in the OEC of PSII. Both superoxide anion and hydroxyl radical located inside the PSII membrane were directly identified by a spin trapping-electron spin resonance (ESR) method in combination with a lipophilic spin trap, 5-(diethoxyphosphoryl)-5-phenethyl-1-pyrroline N-oxide (DEPPEPO). The endogenous hydrogen peroxide production was examined by oxidation of thiobenzamide.

Electron Spin Resonance Spectroscopy↗
PubMed2007

Current status of the role of Cl(-) ion in the oxygen-evolving complex.

This minireview summarizes the current state of knowledge concerning the role of Cl(-) in the oxygen-evolving complex (OEC) of photosystem II (PSII). The model that proposes that Cl(-) is a Mn ligand is discussed in light of more recent work. Studies of Cl(-) specificity, stoichiometry, kinetics, and retention by extrinsic polypeptides are discussed, as are the results that fail to detect Cl(-) ligation to Mn and results that show a lack of a requirement for Cl(-) in PSII-catalyzed H(2)O oxidation. Mutagenesis experiments in cyanobacteria and higher plants that produce evidence for a correlation between Cl(-) retention and stable interactions among intrinsic and extrinsic polypeptides are summarized, and spectroscopic data on the interaction between PSII and Cl(-) are discussed. Lastly, the question of the site of Cl(-) action in PSII is discussed in connection with the current crystal structures of the enzyme.

Chlorides↗
PubMed2005

Evolving concepts regarding transient ischemic attacks.

Transient ischemic attack (TIA) represents one end of the spectrum of focal brain ischemia, the other being completed infarction or ischemic stroke. The evolving technologic advancements in neuroimaging continue to change and sharpen the definition, epidemiology, and management of TIA. As a powerful risk factor for ischemic stroke, TIA deserves widespread public and physician education, urgent attention and investigation, and rapid management. The recognition and treatment of TIA provides an excellent opportunity for stroke prevention that is often missed or poorly recognized among physicians.

Animals↗
PubMed2001

Evolving medical therapies for ulcerative colitis.

Patients with ulcerative colitis have traditionally relied on sulfasalazine, mesalamine, and corticosteroids as the mainstay of medical therapy. Steroid-refractory, -dependent, or -intolerant patients have resorted to agents such as cyclosporine for short-term efficacy and 6-mercaptopurine or azathioprine for long-term efficacy. The next generation of evolving therapies includes many novel agents that target various aspects of the human immune response. Therapies that block the production or action of tumor necrosis factor have received much interest in inflammatory bowel disease. Treatments currently under study include interleukins, interferons, T-cell selective antibodies, molecules involved in cellular trafficking and signaling, mucosal healing or growth factors, and novel steroid agents. Other "less traditional" therapies, including probiotics, heparins, and anti-gastric ulcer remedies, challenge our understanding of the pathogenesis of ulcerative colitis and may provide further insights into future therapies.

Colitis, Ulcerative↗
PubMed2001

Evolving medical therapies for Crohn's disease.

Medical therapy for Crohn's disease has changed dramatically over the past few years. Physicians have become increasingly willing to use traditional immunosuppressive agents such as azathioprine/6-mercaptopurine (6-MP) and methotrexate as well as new biologic therapies such as infliximab. Azathioprine, 6-MP, and methotrexate have demonstrated efficacy in induction and maintenance of remission in Crohn's disease. 6-MP has also demonstrated efficacy in the pediatric population and possibly as first-line therapy. As use of the purine metabolites grows, therapeutic drug monitoring for efficacy and toxicity will become an emerging area of interest. With respect to the biologic therapies, infliximab is increasingly used to treat patients with difficult disease; however, knowledge is still evolving regarding optimal dosing schedules and the significance of immune reactions to the compound. A humanized anti-tumor necrosis factor antibody, CDP571, may be less immunogenic. Interleukin-10 did not consistently demonstrate benefit in Crohn's disease. Similarly, antisense to intracellular adhesion molecule 1 (ISIS 2302) was not efficacious when administered either subcutaneously or intravenously. Finally, growth hormone has shown promising results in a small trial.

Crohn Disease↗
PubMed1999

Superbugs: How They Evolve and Minimize the Cost of Resistance.

The increasing frequency with which antimicrobial-resistant microorganisms have emerged in hospitals and communities has alarmed public health officials worldwide. The emergence of resistance results from the evolution of the sometimes elegant resistance mechanisms that create so-called superbugs, which disseminate by clonal spread or exchange resistance traits with other microorganisms. One major contributor to the emergence of resistance is selection intensity, which is determined by the volume of drug consumption by humans and the agriculture industry. De novo or acquired resistance is often initially associated with a cost to fitness of the microorganism. It therefore seems reasonable to assume that reducing the volume of drug use would slow the evolution and reduce the prevalence of resistance. This assumption has led to worldwide attempts to control the inappropriate use of antimicrobials in the hope of controlling the pandemic of antibiotic resistance. However, microorganisms have learned to adapt in order to survive in ever-changing environments. Superbugs have evolved numerous mechanisms that reduce or eliminate the cost of resistance, and such adaptations may minimize the potential benefits of programs aimed at reducing the volume of drug use. It therefore behooves us to look to other disciplines--such as population genetics, ecology, and mathematical biology--to help us tackle this perplexing and important problem.

Journal Article↗
PubMed1981

Intracoronary thrombolysis in evolving myocardial infarction.

After experimental studies in dogs confirmed the feasibility and safety of rapid intracoronary thrombolysis by local infusion of Thrombolysin (streptokinase and plasmin), intracoronary thrombolysis was attempted in 20 patients with evolving myocardial infarction who were hospitalized within 3 hours from the onset of symptoms during the day and within 2 hours at night. Thrombolysin was infused in the immediate vicinity of the site of coronary occlusion using a 0.85 mm outer diameter catheter advanced through the lumen of the Judkins catheter. Reperfusion was achieved in four patients after an average of 43 minutes of Thrombolysin infusion at a rate of 2000 IU/min and in 15 patients after an average of 21 minutes of Thrombolysin infusion at a rate of 4000 IU/min. The failure to open the artery in one patient may have been caused by our inability to advance the infusion catheter close to the site of occlusion. Rethrombosis occurred in one patient 8 days after reperfusion and 2 days after discontinuation of anticoagulants because of a history of chronic alcoholism. Wall motion and perfusion studies showed improvement following reperfusion. Patency of the artery was achieved an average of 4 hours after the onset of symptoms. The need for earlier reperfusion is emphasized.

Adult↗
PubMed1981

Changes in left ventricular function after intracoronary streptokinase infusion in clinically evolving myocardial infarction.

Left ventricular (LV) contrast cineventriculograms were obrained in 174 patients with evolving acute myocardial infarction (AMI) treated by intracoronary streptokinase (SK) infusion. Ejection fraction (EF) increased slightly, from 52% +/- 13% before admission SK intervention to 58% +/- 13% immediately after early recanalization of the completely obstructed coronary vessel (p less than 0.0005, n = 68), while local wall motion usually improved. Immediately improved LV function appears to be the result of early reperfusion and/or decreased LV afterload. In 55 chronic (long-term follow-up) post-AMI (2 to 4 weeks after successful early SK reperfusion) patients, repeat angiography revealed late reocclusion of the infarct vessel in nine patients. Chronic EF was not significantly different from pre-SK intervention EF in these nine patients with late reocclusion, whereas in the remaining 46 patients with persistent patency, EF increased mildly from 52% +/- 13% (before SK intervention) to 56% +/- 16% (in long-term recanalization) (p less than 0.025). Ventricular loading conditions were not different at pre-SK intervention angiography and chronic angiography. EF rose modestly from 51% +/- 14% to 57% +/- 18% in the 23 patients recanalized on follow-up, in whom pre-SK intervention angiography revealed collaterals to the infarcting area (p less than 0.025), whereas there was no EF change in the 23 chronically recanalized patients without pre-SK collaterals. In the eight patients recanalized at late follow-up, who had preadmission chest pain for less than 3 hours and successful SK reperfusion within 4 hours of symptom onset (group A), EF increased significantly from 51% +/- 12% to 65% +/- 6% (p less than 0.025). In the 25 chronically recanalized patients admitted 3 to 6 hours after onset of chest pain, in whom SK reperfusion was successful (group B), EF was unchanged at late study. In the 13 chronically recanalized patients with preadmission chest pain lasting longer than 6 hours, in whom SK reperfusion was successful (group C), EF increased from 52% +/- 13% before SK intervention to 56% +/- 16% at late study (p less than 0.025). Pre-SK intervention angiography revealed collateral vessels to the infarct area in 69% of group C patients but in only 42% of patients in groups A and B. These findings suggest that the critical interval for myocardial salvage, as well as for early and long-term improvement of LV function by SK reperfusion at admission, is 4 hours after onset of chest pain in the majority of AMI patients. This time interval may be longer in patients with well-developed collateral supply to the region of the acute infarct.

Cardiac Output↗
PubMed1982

Beneficial effects of intracoronary thrombolysis up to eighteen hours after onset of pain in evolving myocardial infarction.

Coronary arteriography and intracoronary streptokinase (STK) infusion were performed on 89 patients with evolving acute myocardial infarction (AMI). Ventricular function was followed in these patients during their hospitalization by gated radionuclide ventriculography. In 35 of these patients thallium imaging was performed on admission and 4 hours after reperfusion. An additional 30 patients with AMI who either met exclusion criteria for the STK protocol or refused study served as a control group. In patients admitted 0 to 6, 6 to 12, or 12 to 18 hours after onset of pain, there was no difference in change in left ventricular ejection fraction (LVEF) from admission to discharge, in percent of patients with total occlusion demonstrating reperfusion, or in percent of patients demonstrating a significant increase in LVEF. The average increase in LVEF from admission to discharge in patients reperfused ws 8% (40% +/- 14% to 48% +/- 13%, p less than 0.001). No change in LVEF was demonstrated in the control population or in patients in whom coronary reperfusion was unsuccessful. Reperfusion produced an increase in thallium uptake in the infarct-related myocardium that was accompanied by an improvement in regional function. Failure of reperfusion produced no change in either thallium uptake or regional function.

Adult↗
PubMed1984

Intracoronary streptokinase in evolving acute myocardial infarction.

Intracoronary application of thrombolytic agents, particularly streptokinase, can recanalize arteries that had been totally occluded in patients with evolving acute myocardial infarction (AMI). Numerous uncontrolled trials have testified to the effectiveness of thrombolytic therapy in most patients in reestablishing flow to the infarct-related coronary artery. Follow-up of patients in whom reperfusion has been established has often demonstrated small but significant increases in the left ventricular ejection fraction. In contrast, in other patients in whom thrombolytic therapy failed to reopen the occluded vessel, the left ventricular ejection fraction usually does not change during follow-up. In most reported uncontrolled trials, few complications are described and the mortality rate in patients treated by this therapy may be lower than expected. These data have been used as the basis for widespread application of this technique in many catheterization laboratories around the world. Our initial experience at the University of Florida in 23 patients has not been as successful as other uncontrolled trials previously reported. Reperfusion was accomplished in only 12 patients. Of 17 who survived their AMI, only five demonstrated an improved left ventricular ejection fraction of at least 10%. Serious complications, including bleeding from catheterization sites or allergic reactions to streptokinase, occurred. Controlled trials to critically evaluate this new therapy are needed and are in progress.

Clinical Trials as Topic↗
PubMed1985

Percutaneous transluminal coronary angioplasty after intracoronary streptokinase in evolving acute myocardial infarction.

To achieve optimal myocardial revascularization and prevent rethrombosis of the infarct-related coronary artery, percutaneous transluminal coronary angioplasty (PTCA) was attempted in 18 patients with evolving acute myocardial infarction (9 anterior and 9 inferior) after administration of intracoronary streptokinase. PTCA was attempted 338 +/- 151 minutes after the onset of symptoms. After thrombolytic therapy, 11 patients had a severe residual stenosis and 7 a persistent total occlusion of the infarct-related coronary artery. PTCA was successful in 13 of 18 patients: in 9 of 11 with coronary stenoses and in 4 of 7 with total coronary occlusions. PTCA reduced the severity of the coronary lesion from 91 +/- 2% to 27 +/- 7% (p less than 0.001), and the transstenotic pressure gradient from 38 +/- 5 to 6 +/- 2 mm Hg (p less than 0.01). One patient in cardiogenic shock died during urgent coronary surgery after unsuccessful PTCA. After PTCA, all patients received heparin and antiplatelet agents. One patient had reinfarction with reocclusion of the infarct-related artery 5 days after PTCA. The other 12 patients had an uneventful hospital course, and cardiac catheterization before hospital discharge (8 to 17 days) revealed reocclusion of the infarct-related coronary artery in 3 and persistent patency in 9. Persistent patency of the infarct-related artery was associated with preservation of left ventricular end-diastolic volume (initial 86 +/- 6 ml/m2, follow-up 91 +/- 6 ml/m2), and improvement in left ventricular ejection fraction in some patients.

Adult↗
PubMed1986

Ratio of ST-segment depression in lead V2 to ST-segment elevation in lead aVF in evolving inferior acute myocardial infarction: an aid to the early recognition of right ventricular ischemia.

The potential value of the ratio of precordial ST-segment depression to inferior ST-segment elevation as a sign of concomitant right ventricular (RV) ischemia was examined. The study group consisted of 68 patients, admitted within 3 hours of the onset of inferior acute myocardial infarction (AMI), in whom there was no evidence of prior AMI. In 27 of the 34 patients in whom inferior AMI was the result of right coronary artery occlusion proximal to the RV branch, the magnitude of ST-segment depression in lead V2 was 50% or less of the magnitude of ST-segment elevation in lead aVF, whereas in only 3 of the 34 patients in whom the site of occlusion was either distal to the RV branch (n = 23) or in the left circumflex artery (n = 11) was this ratio 50%; in no patient was it less than 50% (p less than 0.001). All 34 patients with occlusion of the right coronary artery proximal to the RV branch also had regional or global ischemic RV dysfunction by radionuclide ventriculography, with a mean RV ejection fraction of 30 +/- 10% compared with 42 +/- 6% in patients with occlusion distal to the RV branch or in the left circumflex artery (p less than 0.001). In conclusion, in patients with evolving inferior AMI, ST-segment depression in lead V2 of 50% or less of the magnitude of ST-segment elevation in lead aVF may be a useful sign (sensitivity 79%, specificity 91%, positive predictive value 90% and negative predictive value 82%) for identifying patients with concomitant RV ischemia.

Adult↗
PubMed1989

Relation of electrocardiographic abnormalities to evolving left ventricular hypertrophy in hypertrophic cardiomyopathy during childhood.

Patients with hypertrophic cardiomyopathy (HC) often show substantial increases in left ventricular (LV) wall thickness or even de novo development of LV hypertrophy during childhood. To determine the utility of the electrocardiogram in reflecting such changes in LV mass, serial 12-lead electrocardiograms and 2-dimensional echocardiograms were analyzed in 38 children with HC. The period of evaluation ranged from 3 to 8 years (mean 5.5). Between the initial and most recent clinical evaluations, precordial and standard lead voltages did not change significantly in the study patients, including those showing evolution of LV hypertrophy by 2-dimensional echocardiography; furthermore, only 9 of the 38 patients (23%) showed any substantial change in the overall electrocardiographic pattern. However, the magnitude of electrocardiographic voltages at initial evaluation (age 11 +/- 4 years) showed a significant correlation with the extent of LV hypertrophy at the most recent evaluation as assessed by echocardiography (at age 16 +/- 4 years) (r = 0.65, p less than 0.001). Of note, each of the 7 patients who developed LV hypertrophy during the period of observation had distinct electrocardiographic abnormalities at the initial evaluation that preceded the appearance of LV hypertrophy on the echocardiogram. In conclusion, in children with HC and evolving LV hypertrophy, the electrocardiogram showed little change during the period of observation. However, electrocardiographic abnormalities may be the initial manifestation of HC, appearing even before LV hypertrophy is detectable by echocardiography. Hence, in patients with HC the electrocardiogram may provide advance evidence of morphologic changes that will subsequently occur and may describe the magnitude of LV hypertrophy ultimately achieved an average of 5 years later.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

Evolving concepts in the mechanism of steroid action: current developments.

The mechanisms of steroid action remain a poorly understood enigma. Although much effort has focused on the steroid receptor as a mediator of the steroid's effect in the cell, we are only beginning to understand the structure of steroid receptors. Development of monoclonal antibodies directed against both the steroid-binding "receptors" and receptor-associated proteins has allowed novel approaches to the problem. They were important in determining the nucleotide sequences of several receptor genes and subsequently the amino acid sequence of three receptors. Surprisingly, receptors contain amino acid sequences common to v-erb-A, a potentiator of oncogenic transformation. Two receptor-associated proteins have been found and their relationship to the receptors suggests the possibility of additional functions of receptors in addition to binding deoxyribonucleic acid. Thus the role of the receptor in the mechanism of steroid action is evolving from the "two-step mechanism" to one that includes the recently discovered receptor-associated proteins.

Antibody Formation↗
PubMed1990

Human oocyte and preembryo donation: an evolving method for the treatment of infertility.

The utilization of oocyte and preembryo donation in the treatment of infertility has recently expanded. Since 1983, modifications in the retrieval of donated female gametes have enhanced both the safety and the efficacy of the procedure. Pregnancy rates in women receiving donated preembryos are remarkably high, with success occurring in 25% to 50% of transfer cycles. The technology used for preembryo donation continues to evolve, and the current and future role ovum donation in the treatment of infertility.

Adult↗