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Publication
Journal: European Psychiatry
January/9/2008
Abstract
The insular cortex is located in the centre of the cerebral hemisphere, having connections with the primary and secondary somatosensory areas, anterior cingulate cortex, amygdaloid body, prefrontal cortex, superior temporal gyrus, temporal pole, orbitofrontal cortex, frontal and parietal opercula, primary and association auditory cortices, visual association cortex, olfactory bulb, hippocampus, entorhinal cortex, and motor cortex. Accordingly, dense connections exist among insular cortex neurons. The insular cortex is involved in the processing of visceral sensory, visceral motor, vestibular, attention, pain, emotion, verbal, motor information, inputs related to music and eating, in addition to gustatory, olfactory, visual, auditory, and tactile data. In this article, the literature on the relationship between the insular cortex and neuropsychiatric disorders was summarized following a computer search of the Pub-Med database. Recent neuroimaging data, including voxel based morphometry, PET and fMRI, revealed that the insular cortex was involved in various neuropsychiatric diseases such as mood disorders, panic disorders, PTSD, obsessive-compulsive disorders, eating disorders, and schizophrenia. Investigations of functions and connections of the insular cortex suggest that sensory information including gustatory, olfactory, visual, auditory, and tactile inputs converge on the insular cortex, and that these multimodal sensory information may be integrated there.
Publication
Journal: Prostaglandins and Other Lipid Mediators
July/17/2005
Abstract
The molecular basis for the beneficial impact of essential omega-3 fatty acids is of considerable interest. Recently, novel mediators generated from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) that displayed potent bioactions were first identified in resolving inflammatory exudates [J. Exp. Med. 192 (2000) 1197; J. Exp. Med. 196 (2002) 1025] and in tissues enriched with DHA [J. Exp. Med. 196 (2002) 1025; J. Biol. Chem. 278 (2003) 14677]. The trivial names Resolvin (resolution phase interaction products) and docosatrienes were introduced for the bioactive compounds belonging to these novel series because they demonstrate potent anti-inflammatory and immunoregulatory actions. The compounds derived from eicosapentaenoic acid carrying potent biological actions (i.e., 1-10 nM range) are designated E series, given their EPA precursor, and denoted as Resolvins of the E series (Resolvin E1 or RvE1), and those biosynthesized from the precursor docosahexaenoic acid are Resolvins of the D series (Resolvin D1 or RvD1). Bioactive members from DHA with conjugated triene structures are docosatrienes (DT) that are immunoregulatory [J. Exp. Med. 196 (2002) 1025; J. Biol. Chem. 278 (2003) 14677], and neuroprotective [J. Biol. Chem., 278 (2003) 43807; Proc. Natl. Acad. Sci. U.S.A. [submitted for publication]] and are termed neuroprotectins. The specific receptors for these novel bioactive products from omega-3 EPA and DHA are abbreviated Resolvin D receptors (i.e., ResoDR1), Resolvin E receptor (ResoER1; RER1), and neuroprotectin D receptors (NPDR), respectively, in recognition of their respective cognate ligands. Aspirin treatment impacts biosynthesis of these compounds and a related series by triggering endogenous formation of the 17R-D series Resolvins and docosatrienes. These novel epimers are denoted as aspirin-triggered (AT)-RvDs and -DTs, and possess potent anti-inflammatory actions in vivo essentially equivalent to their 17S series pathway products. Here, we provide a syntomy overview of the formation and actions of these newly uncovered pathways and products as well as highlight their role(s) as endogenous protective mediators generated in anti-inflammation and catabasis.
Publication
Journal: American journal of medical genetics
October/17/1999
Abstract
Plexiform neurofibromas are among the most common and debilitating complications of neurofibromatosis type 1 (NF1). They account for substantial morbidity, including disfigurement, functional impairment, and may even be life threatening. Plexiform neurofibromas are also subject to transformation into malignant peripheral nerve sheath tumor (MPNST), a complication that is refractory to treatment both because of a paucity of effective therapies for malignant soft tissue sarcomas in general, and because of the delay in diagnosis that results from change of a small portion of a large pre-existing tumor. The current mainstay of treatment of plexiform neurofibromas, and of MPNST for that matter, is surgical resection. The major variables are the timing and means of identification of plexiform neurofibromas, methods of follow-up, and indications for surgery. There is no established means of medical treatment, but research into the molecular pathogenesis of NF1, as well as advances in tumor therapy in general, are opening the way towards clinical trials for plexiform neurofibroma. Am. J. Med. Genet. (Semin. Med. Genet.) 89:31-37, 1999.
Authors
Publication
Journal: Contemporary Clinical Trials
March/26/2006
Abstract
OBJECTIVE
To examine reasons given for the use of unequal randomisation in randomised controlled trials (RCTs).
METHODS
Setting of the trial; intervention being tested; randomisation ratio; sample size calculation; reason given for randomisation.
METHODS
Review of trials using unequal randomisation. DATABASES AND SOURCES: Cochrane library, Medline, Pub Med and Science Citation Index.
RESULTS
A total of 65 trials were identified; 56 were two-armed trials and nine trials had more than two arms. Of the two-arm trials, 50 trials recruited patients in favour of the experimental group. Various reasons for the use of unequal randomisation were given. Six studies stated that they used unequal randomisation to reduce the cost of the trial, with one screening trial limited by the availability of the intervention. Other reasons for using unequal allocation were: avoiding loss of power from drop-out or cross-over, ethics and the gaining of additional information on the treatment. Thirty seven trials papers (57%) did not state why they had used unequal randomisation and only 14 trials (22%) appeared to have taken the unequal randomisation into account in their sample size calculation.
CONCLUSIONS
Although unequal randomisation offers a number of advantages to trials the method is rarely used and is especially under-utilised to reduce trial costs. Unequal randomisation should be considered more in trial design especially where there are large differences between treatment costs.
Publication
Journal: Magnetic Resonance in Medicine
September/27/1999
Abstract
The exact, hardware-constrained design of a spiral k-space trajectory requires the solution of a differential equation, thereby making real-time prescription difficult on scanners with limited computational power. This study describes a closed-form approximate solution for interleaved Archimedian spiral trajectories that closely matches the exact design. Both slew rate-limited and amplitude-limited regimes are incorporated. Magn Reson Med 42:412-415, 1999.
Authors
Publication
Journal: Journal of Virology
November/14/2005
Abstract
The increased transmission and geographic spread of dengue fever (DF) and its more severe presentation, dengue hemorrhagic fever (DHF), make it the most important mosquito-borne viral disease of humans (50 to 100 million infections/year) (World Health Organization, Fact sheet 117, 2002). There are no vaccines or treatment for DF or DHF because there are no animal or other models of human disease; even higher primates do not show symptoms after infection (W. F. Scherer, P. K. Russell, L. Rosen, J. Casals, and R. W. Dickerman, Am. J. Trop. Med. Hyg. 27:590-599, 1978). We demonstrate that nonobese diabetic/severely compromised immunodeficient (NOD/SCID) mice xenografted with human CD34+ cells develop clinical signs of DF as in humans (fever, rash, and thrombocytopenia), when infected in a manner mimicking mosquito transmission (dose and mode). These results suggest this is a valuable model with which to study pathogenesis and test antidengue products.
Publication
Journal: Annals of periodontology
March/8/2004
Abstract
BACKGROUND
Periodontal diseases are infections and thus systemically administered antibiotics are often employed as adjuncts for their control. There are conflicting reports as to whether these agents provide a therapeutic benefit.
BACKGROUND
The purpose of this systematic review is to determine whether systemically administered antibiotics improve a primary clinical outcome measure, periodontal attachment level change.
OBJECTIVE
In patients with periodontitis, what is the effect of systemically administered antibiotics as compared to controls on clinical measures of attachment level?
METHODS
The Pub/Med database was searched from 1966 to May 2002. Searches were limited to human studies published in English. Hand searches were performed on the Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research. References in relevant papers and review articles were also examined.
METHODS
METHODS
Trials were selected if they met the following criteria: randomized controlled clinical trials, quasi-experimental studies, and cohort studies of>> 1 month duration with a comparison group; subjects with aggressive, chronic, or recurrent periodontitis and periodontal abscess; use of a single or a combination of systemically administered antibiotics(s) versus non-antibiotic therapy; and a primary outcome of mean attachment level change (AL).
METHODS
Studies involving the use of low-dose doxycycline, combinations of locally plus systemic antibiotics, or where the control group included a systemically administered antibiotic were excluded.
METHODS
A mean difference in AL between groups was available for all papers used in the meta-analysis. A standard deviation (SD) for the difference was used if provided or calculated from the SD or standard error of the mean (SEM) when provided for single measurements. Data were subset by antibiotic employed, type of adjunctive therapy, and disease type. Results were assessed with both fixed-effects and random-effects models.
RESULTS
1. Twenty-nine studies, 26 RCTs and 3 quasi-experimental (36 comparisons), met the entry criteria. Total study population, both control and test groups, was estimated at over 1,200. 2. Twenty-two studies (27 comparisons) were used in the meta-analysis, evaluating if the antibiotics provided a consistent benefit in mean AL change for different patient populations, for different therapies, and for different antibiotics. 3. For the majority of the comparisons, systemically administered antibiotics exhibited a more positive attachment level change than the control group in the study. The combined results were statistically significant (P < 0.001). 4. The systemic antibiotics were uniformly beneficial in providing an improvement in AL when used as adjuncts to scaling and root planing (SRP) and were consistently beneficial, although of borderline significance, when used as adjuncts to SRP plus surgery or as a stand alone therapy. 5. When examining the effects of individual or combinations of antibiotics, it was found that there were statistically significant improvements in AL for tetracycline, metronidazole, and an effect of borderline statistical significance for the combination of amoxicillin plus metronidazole. 6. Improvements in mean AL were consistent for both chronic and aggressive periodontitis subjects, although the aggressive periodontitis patients benefited more from the antibiotics.
CONCLUSIONS
1. The use of systemically administered adjunctive antibiotics with and without SRP and/or surgery appeared to provide a greater clinical improvement in AL than therapies not employing these agents. 2. The data supported similar effect sizes for the majority of the antibiotics; therefore, the selection for an individual patient has to be made based on other factors. 3. Due to a lack of sufficient sample size for many of the antibiotics tested, it is difficult to provide guidance as to the more effective ones.
Publication
Journal: Archives of family medicine
January/17/2001
Abstract
OBJECTIVE
To evaluate a cohort of patients with major depression to examine the effect of competing demands on depression care during multiple visits over 6 months.
METHODS
Ninety-two patients with 5 or more symptoms of depression and no recent depression treatment were evaluated by 12 primary care physicians in 6 practices in the usual-care arm of an effectiveness trial of the Agency for Health Care Policy and Research Depression Guidelines.
METHODS
Treatment was considered to be initiated if the patient reported starting a guideline-concordant antidepressant medication or making a visit for specialty counseling. Treatment completion was defined as either a 3-month course of guideline-concordant antidepressant use or completion of 8 or more specialty counseling visits.
RESULTS
Among the 92 patients reporting no recent treatment at study enrollment, 57% reported starting and 17% reported completing a course of guideline-concordant antidepressant medication and or specialty counseling at the 6-month interview. The severity of physical problems among patients with high enthusiasm for depression treatment decreased the odds that patients would initiate depression therapy. Severity of physical problems had no observable effect on completing depression therapy in the group of patients who initiated treatment.
CONCLUSIONS
Physical problems compete with depression for attention over multiple visits in untreated patients who are enthusiastic about getting care for their emotional problems. Interventions are needed for this high-risk group, because depression treatment could potentially enhance patients' treatment of their physical problems. Arch Fam Med. 2000;9:1059-1064
Publication
Journal: Magnetic Resonance in Medicine
October/18/2000
Abstract
Hyperpolarized (3)He gas MRI was used to form maps of the effective diffusivity of gas in human lungs. Images of diffusion as well as spin density are presented from a study of 11 healthy volunteers and 5 patients with severe emphysema. The effective rate of diffusion, D(e), of the gas is reduced by the alveolar walls; tissue destruction in emphysema is hypothesized to result in larger D(e). Indeed, the mean value of D(e) in the emphysematous lungs is found here to be about 2.5 times that of healthy lungs, although still smaller than the unrestricted diffusivity of (3)He in free air. Histograms of D(e) values across coronal slices are presented. The results are discussed in terms of spatial variations, variations among individuals, healthy and diseased, and variations due to changes in lung volume. Magn Reson Med 44:174-179, 2000.
Publication
Journal: Gastroenterology
September/26/2013
Abstract
OBJECTIVE
Identification of intestinal stem cells (ISCs) has relied heavily on the use of transgenic reporters in mice, but this approach is limited by mosaic expression patterns and difficult to directly apply to human tissues. We sought to identify reliable surface markers of ISCs and establish a robust functional assay to characterize ISCs from mouse and human tissues.
METHODS
We used immunohistochemistry, real-time reverse-transcription polymerase chain reaction, and fluorescence-activated cell sorting (FACS) to analyze intestinal epithelial cells isolated from mouse and human intestinal tissues. We compared different combinations of surface markers among ISCs isolated based on expression of Lgr5-green fluorescent protein. We developed a culture protocol to facilitate the identification of functional ISCs from mice and then tested the assay with human intestinal crypts and putative ISCs.
RESULTS
CD44(+)CD24(lo)CD166(+) cells, isolated by FACS from mouse small intestine and colon, expressed high levels of stem cell-associated genes. Transit-amplifying cells and progenitor cells were then excluded based on expression of GRP78 or c-Kit. CD44(+)CD24(lo)CD166(+) GRP78(lo/-) putative stem cells from mouse small intestine included Lgr5-GFP(hi) and Lgr5-GFP(med/lo) cells. Incubation of these cells with the GSK inhibitor CHIR99021 and the E-cadherin stabilizer Thiazovivin resulted in colony formation by 25% to 30% of single-sorted ISCs.
CONCLUSIONS
We developed a culture protocol to identify putative ISCs from mouse and human tissues based on cell surface markers. CD44(+)CD24(lo)CD166(+), GRP78(lo/-), and c-Kit(-) facilitated identification of putative stem cells from the mouse small intestine and colon, respectively. CD44(+)CD24(-/lo)CD166(+) also identified putative human ISCs. These findings will facilitate functional studies of mouse and human ISCs.
Publication
Journal: Virology
April/30/2002
Abstract
Herpes simplex virus type 1 (HSV-1) is resistant to the antiviral effects of interferon (IFN)-alpha, -beta, or -gamma. The fact that ICP0(-) mutants replicate like wild-type virus in IFN-alpha/beta receptor knockout mice (Leib et al., 1999, J. Exp. Med. 189, 663) suggested that ICP0 may serve a direct role in the resistance of HSV-1 to IFN. To test this hypothesis, the effects of IFN-alpha, -beta, and -gamma were compared against wild-type HSV-1 and an ICP0(-) mutant virus, 7134. In Vero cells, 7134 was more sensitive to inhibition by low doses of type I IFN (-alpha/beta) or type II IFN (-gamma) than vesicular stomatitis virus, a well-studied IFN-sensitive virus. At a concentration of 100 U/ml, IFN-alpha, -beta, or -gamma reduced the efficiency of 7134 plaque formation by 120-, 560-, and 45-fold, respectively. In contrast, none of the IFNs reduced wild-type HSV-1 plaque formation by more than 3-fold. Even when Vero cells were infected with 10 pfu per cell, IFN-alpha and -beta inhibited 7134 replication by over 100-fold, but inhibition by IFN-gamma decreased to less than 10-fold. While IFN-beta efficiently inhibited 7134 replication in primary mouse kidney and SK-N-SH cells, IFN-gamma did not inhibit 7134 to a comparable extent in these cells. ICP0 provided in trans from an adenovirus vector allowed 7134 to replicate efficiently in Vero cells in the presence of IFN-alpha, -beta, or -gamma. While IFN-beta or -gamma efficiently repressed the ICP0 promoter-lacZ reporter gene in 7134 (i.e., approximately 60-fold reduction in beta-galactosidase activity), ICP0 provided in trans almost completely reversed IFN-mediated repression of the lacZ gene in 7134. The results suggest that the rate of ICP0 expression in infected cells in vivo may be critical in determining whether host IFNs repress the HSV-1 genome. This concept is discussed in light of its potential relevance to the establishment of latent HSV-1 infections.
Publication
Journal: Magnetic Resonance in Medicine
January/23/2000
Abstract
This study reports the first measurement of the relative cerebral metabolic rate of oxygen utilization (rCMRO(2)) during functional brain activation with sufficient temporal resolution to address the dynamics of blood oxygen level-dependent (BOLD) MRI signal. During rat forepaw stimulation, rCMRO(2) was determined in somatosensory cortex at 3-sec intervals, using a model of BOLD signal and measurements of the change in BOLD transverse relaxation rate, the resting state BOLD transverse relaxation rate, relative cerebral blood flow (rCBF), and relative cerebral blood volume (rCBV). Average percentage changes from 10 to 30 sec after onset of forepaw stimulation for rCBF, rCBV, rCMRO(2), and BOLD relaxation rate were 62 +/- 16, 17 +/- 2, 19 +/- 17, and -26 +/- 12, respectively. A poststimulus undershoot in BOLD signal was quantitatively attributed to the temporal mismatch between changes in blood flow and volume, and not to the role of oxygen metabolism. Magn Reson Med 42:944-951, 1999.
Publication
Journal: Magnetic Resonance in Medicine
August/2/2000
Abstract
An interleaved gradient-echo (GE) / spin-echo (SE) EPI sequence was used to acquire images during the first pass of a susceptibility contrast agent, in patients with brain tumors. Maps of 1) GE (total) rCBV (relative cerebral blood volume), 2) SE (microvascular) rCBV, both corrected for T(1) leakage effects, and 3) (DeltaR(2)*/DeltaR(2)), a potential marker of averaged vessel diameter, were determined. Both GE rCBV and DeltaR(2)*/DeltaR(2) correlated strongly with tumor grade (P = 0.01, P = 0.01, n = 15), while SE rCBV did not (P = 0.24, n = 15). When the GE rCBV data were not corrected for leakage effects, the correlation with tumor grade was no longer significant (P = 0.09, n = 15). These findings suggest that MRI measurements of total blood volume fraction (corrected for agent extravasation) and DeltaR(2)*/DeltaR(2), as opposed to maps of microvascular volume, may prove to be the most appropriate markers for the evaluation of tumor angiogenesis (the induction of new blood vessels) and antiangiogenic therapies. Magn Reson Med 43:845-853, 2000.
Publication
Journal: European Urology
September/10/2014
Publication
Journal: Pain
November/22/2010
Abstract
The use of chronic opioid therapy (COT) for chronic non-cancer pain (CNCP) has increased dramatically in the past two decades. There has also been a marked increase in the abuse of prescribed opioids and in accidental opioid overdose. Misuse of prescribed opioids may link these trends, but has thus far only been studied in small clinical samples. We therefore sought to validate an administrative indicator of opioid misuse among large samples of recipients of COT and determine the demographic, clinical, and pharmacological risks associated with possible and probable opioid misuse. A total of 21,685 enrollees in commercial insurance plans and 10,159 in Arkansas Medicaid who had at least 90 days of continuous opioid use 2000-2005 were studied for one year. Criteria were developed for possible and probable opioid misuse using administrative claims data concerning excess days supplied of short-acting and long-acting opioids, opioid prescribers and opioid pharmacies. We estimated possible misuse at 24% of COT recipients in the commercially insured sample and 20% in the Medicaid sample and probable misuse at 6% in commercially insured and at 3% in Medicaid. Among non-modifiable factors, younger age, back pain, multiple pain complaints and substance abuse disorders identify patients at high risk for misuse. Among modifiable factors, treatment with high daily dose opioids (especially >120 mg MED per day) and short-acting Schedule II opioids appears to increase the risk of misuse. The consistency of the findings across diverse patient populations and the varying levels of misuse suggest that these results will generalize broadly, but await confirmation in other studies.
Publication
Journal: Magnetic Resonance in Medicine
October/20/2015
Abstract
OBJECTIVE
To develop a fast and flexible free-breathing dynamic volumetric MRI technique, iterative Golden-angle RAdial Sparse Parallel MRI (iGRASP), that combines compressed sensing, parallel imaging, and golden-angle radial sampling.
METHODS
Radial k-space data are acquired continuously using the golden-angle scheme and sorted into time series by grouping an arbitrary number of consecutive spokes into temporal frames. An iterative reconstruction procedure is then performed on the undersampled time series where joint multicoil sparsity is enforced by applying a total-variation constraint along the temporal dimension. Required coil-sensitivity profiles are obtained from the time-averaged data.
RESULTS
iGRASP achieved higher acceleration capability than either parallel imaging or coil-by-coil compressed sensing alone. It enabled dynamic volumetric imaging with high spatial and temporal resolution for various clinical applications, including free-breathing dynamic contrast-enhanced imaging in the abdomen of both adult and pediatric patients, and in the breast and neck of adult patients.
CONCLUSIONS
The high performance and flexibility provided by iGRASP can improve clinical studies that require robustness to motion and simultaneous high spatial and temporal resolution. Magn Reson Med 72:707-717, 2014. © 2013 Wiley Periodicals, Inc.
Publication
Journal: Psycho-Oncology
January/29/2007
Abstract
BACKGROUND
Physical activity provides a number of physical and psychological benefits to cancer survivors, including lessening the impact of detrimental cancer-related symptoms and treatment side-effects (e.g. fatigue, nausea), and improving overall well-being and quality of life. The purpose of the present pilot study was to examine the physical and psychological benefits afforded by a 7-week yoga program for cancer survivors.
METHODS
Eligible participants (per-screened with PAR-Q/PAR-MED-X) were randomly assigned to either the intervention (n=20) or control group (n=18). All participants completed pre- and post-testing assessments immediately before and after the yoga program, respectively.
RESULTS
The yoga program participants (M age=51.18 (10.33); 92% female) included primarily breast cancer survivors, on average 55.95 (54.39) months post-diagnosis. Significant differences between the intervention and the control group at post-intervention were seen only in psychosocial (i.e. global quality of life, emotional function, and diarrhea) variables (all p's <0.05). There were also trends for group differences, in the hypothesized directions, for the psychosocial variables of emotional irritability, gastrointestinal symptoms, cognitive disorganization, mood disturbance, tension, depression, and confusion (all p's <0.10). Finally, there were also significant improvements in both the program participants and the controls from pre- to post-intervention on a number of physical fitness variables.
CONCLUSIONS
These initial findings suggest that yoga has significant potential and should be further explored as a beneficial physical activity option for cancer survivors. Future research might attempt to include a broader range of participants (e.g. other types of cancer diagnoses, male subjects), a larger sample size, and a longer program duration in an RCT.
Publication
Journal: Human Molecular Genetics
January/21/2008
Abstract
The mammalian genome contains four voltage-gated sodium channel genes that are primarily expressed in the central nervous system: SCN1A, SCN2A, SCN3A and SCN8A. Mutations in SCN1A and SCN2A are responsible for several dominant idiopathic epilepsy disorders, including generalized epilepsy with febrile seizures plus (GEFS+) and severe myoclonic epilepsy of infancy (SMEI). Mutations in SCN8A are associated with cognitive deficits and neuropsychiatric illness in humans and movement disorders in mice; however, a role for SCN8A (Na(v)1.6) in epilepsy has not been investigated. To determine the relationship between Na(v)1.6 dysfunction and seizure susceptibility, we examined the thresholds of two Scn8a mouse mutants, Scn8a(med) and Scn8a(med-jo), to flurothyl- and kainic acid (KA)-induced seizures. Both mutants were more seizure resistant than wild-type littermates, suggesting that altered Na(v)1.6 function reduces neuronal excitability. To determine whether impaired Na(v)1.6 function could ameliorate seizure severity in a mouse model of SMEI, we generated Scn1a(+/-); Scn8a(med-jo/+) double heterozygous mice. Unlike Scn1a(+/-) mice that are more susceptible to flurothyl-induced seizures, Scn1a(+/-); Scn8a(med-jo/+) mice displayed thresholds that were comparable to wild-type littermates. The Scn8a(med-jo) allele was also able to rescue the premature lethality of Scn1a(+/-) mice and extend the lifespan of Scn1a(-/-) mutants. These results demonstrate that genetic interactions can alter seizure severity and support the hypothesis that genetic modifiers contribute to the clinical variability observed in SMEI and GEFS+.
Publication
Journal: Journal of Biological Chemistry
April/6/1998
Abstract
Human high density lipoproteins (HDL) can reduce cholesteryl ester hydroperoxides to the corresponding hydroxides (Sattler W., Christison J. K., and Stocker, R. (1995) Free Radical Biol. & Med. 18, 421-429). Here we demonstrate that this reducing activity extended to hydroperoxides of phosphatidylcholine, was similar in HDL2 and HDL3, was independent of arylesterase and lecithin:cholesteryl acyltransferase activity, was unaffected by sulfhydryl reagents, and was expressed by reconstituted particles containing apoAI or apoAII only, as well as isolated human apoAI. Concomitant with the reduction of lipid hydroperoxides specific oxidized forms of apoAI and apoAII formed in blood-derived and reconstituted HDL. Similarly, specific oxidized forms of apoAI accumulated upon treatment of isolated apoAI with authentic cholesteryl linoleate hydroperoxide. These specific oxidized forms of apoAI and apoAII have been shown previously to contain Met sulfoxide (Met(O)) at Met residues and are also formed when HDL is exposed to Cu2+ or soybean lipoxygenase. Lipid hydroperoxide reduction and the associated formation of specific oxidized forms of apoAI and apoAII were inhibited by solubilizing HDL with SDS or by pretreatment of HDL with chloramine T. The inhibitory effect of chloramine T was dose-dependent and accompanied by the conversion of specific Met residues of apoAI and apoAII into Met(O). Canine HDL, which contains apoAI as the predominant apolipoprotein and which lacks the oxidation-sensitive Met residues Met112 and Met148, showed much weaker lipid hydroperoxide reducing activity and lower extents of formation of oxidized forms of apoAI than human HDL. We conclude that the oxidation of specific Met residues of apoAI and apoAII to Met(O) plays a significant role in the 2-electron reduction of hydroperoxides of cholesteryl esters and phosphatidylcholine associated with human HDL.
Publication
Journal: Infection and Immunity
February/9/2000
Abstract
Group A Streptococcus (GAS) is a human pathogen that commonly infects the upper respiratory tract. GAS serotype M1 strains are frequently isolated from human infections and contain the gene encoding the hypervariable streptococcal inhibitor of complement protein (Sic). It was recently shown that Sic variants were rapidly selected on mucosal surfaces in epidemic waves caused by M1 strains, an observation suggesting that Sic participates in host-pathogen interactions on the mucosal surface (N. P. Hoe, K. Nakashima, S. Lukomski, D. Grigsby, M. Liu, P. Kordari, S.-J. Dou, X. Pan, J. Vuopio-Varkila, S. Salmelinna, A. McGeer, D. E. Low, B. Schwartz, A. Schuchat, S. Naidich, D. De Lorenzo, Y.-X. Fu, and J. M. Musser, Nat. Med. 5:924-929, 1999). To test this idea, a new nonpolar mutagenesis method employing a spectinomycin resistance cassette was used to inactivate the sic gene in an M1 GAS strain. The isogenic Sic-negative mutant strain was significantly (P < 0.019) impaired in ability to colonize the mouse mucosal surface after intranasal infection. These results support the hypothesis that the predominance of M1 strains in human infections is related, in part, to a Sic-mediated enhanced colonization ability.
Publication
Journal: Clinical Immunology
January/3/2000
Abstract
Leflunomide (Arava) has recently been approved by the Food and Drug Administration for the treatment of rheumatoid arthritis (RA). This approval was based on data from a double-blind, multicenter trials in the United States (leflunomide versus methotrexate versus placebo) in which leflunomide was superior to placebo and similar to methotrexate (Strand et al., Arch. Intern. Med., in press, 1999). In a multicenter European trial, leflunomide was similar to sulfasalazine in efficacy and side effects (Smolen et al., Lancet 353, 259-266, 1999). Both methotrexate and leflunomide retarded the rate of radiolographic progression, entitling them to qualify as disease-modifying agents (Strand et al., Arch. Intern. Med., in press, 1999). Leflunomide is an immunomodulatory drug that may exert its effects by inhibiting the mitochondrial enzyme dihydroorotate dehydrogenase (DHODH), which plays a key role in the de novo synthesis of the pyrimidine ribonucleotide uridine monophosphate (rUMP). The inhibition of human DHODH by A77 1726, the active metabolite of leflunomide, occurs at levels (approximately 600 nM) that are achieved during treatment of RA. We propose that leflunomide prevents the expansion of activated and autoimmune lymphocytes by interfering with the cell cycle progression due to inadequate production of rUMP and utilizing mechanisms involving p53. The relative lack of toxicity of A77 1726 on nonlymphoid cells may be due to the ability of these cells to fulfill their ribonucleotide requirements by use of salvage pyrimidine pathway, which makes them less dependent on de novo synthesis.
Publication
Journal: Kidney International
February/10/2003
Abstract
BACKGROUND
Acute renal failure (ARF) is associated with a persistent high mortality in critically ill patients in intensive care units (ICUs). Most studies to date have focused on patients with established, intrinsic ARF or relatively severe ARF due to multiple factors. None have examined outcomes of dialysis-dependent chronic renal failure [end-stage renal disease (ESRD)] patients in the ICU. We examined the incidence and outcomes of ARF in the ICU using a standard definition and compared these to outcomes of ICU patients with either ESRD or no renal failure. We sought to determine the impact of renal dysfunction and/or loss of organ function on outcome.
METHODS
We prospectively scored 1530 admissions to eight ICUs over a 10-month period for illness severity at ICU admission using the Acute Physiological and Chronic Health Evaluation (APACHE III) evaluation tool. Patients were defined as having ARF based on the definition of Hou et al (Am J Med 74:243-248,1983) designed to detect significant measurable declines in renal function based on serum creatinine. ESRD patients were identified as being chronically dialysis-dependent prior to ICU admission and the remainder had no renal failure. Clinical characteristics at ICU admission and ICU and hospital outcomes were compared between the three groups.
RESULTS
We identified 254 cases of ARF, 57 cases of ESRD and 1219 cases of no renal failure for an incidence of ARF of 17%. Roughly half the ARF patients had ARF at ICU admission and the remainder developed ARF during their ICU stay. Only 11% of ARF patients required dialysis support. ARF patients had significantly higher acute illness severity scores than those with no renal failure, whereas patients with ESRD had intermediate severity scores. ICU mortality was 23% for patients with ARF, 11% for those with ESRD, and 5% for those with no renal failure. There was no difference in outcome between patients who had ARF at ICU admission and those who developed ARF in the ICU. Patients with ARF severe enough to require dialysis had a mortality of 57%. APACHE III predicted outcome very well in patients with no renal failure and patients with ARF at the time of scoring but underpredicted mortality in those who developed ARF after ICU admission and overestimated mortality in patients with ESRD.
CONCLUSIONS
ARF is common in ICU patients and has a persistent negative impact on outcomes, although the majority of ARF is not severe enough to require dialysis support. The mortality of patients with ARF from all causes is almost exactly similar to that noted using the same criteria two decades ago. More profound ARF requiring dialysis continues to have an even greater mortality. Nevertheless, acute declines in renal function are associated with a mortality that is not well explained simply by loss of organ function. The majority of ARF patients who did not require dialysis still had a considerably higher mortality than the ESRD patients, all of whom required dialysis; while ARF patients who did require dialysis had a much higher morality than ESRD patients. APACHE III performs well and captures the mortality of patients with ARF at the time of scoring. Development of ARF after scoring has a profound effect on standardized mortality. We were unable to identify a unique mortality associated with ARF, but the presence of measurable renal insufficiency continues to be a sensitive marker for poor outcome.
Publication
Journal: Journal of Cell Biology
July/12/1990
Abstract
Macrophages require activation with either PMA (Mercurio, A. M., and L. M. Shaw. 1988. J. Cell Biol. 107:1873-1880) or interferon-gamma (Shaw, L. M., and A. M. Mercurio. 1989. J. Exp. Med. 169:303-308) to adhere to a laminin substratum. In the present study, we identified an integrin laminin receptor on macrophages and characterized cellular changes that occur in response to PMA activation that facilitate laminin adhesion. A monoclonal antibody (GoH3) that recognizes the integrin alpha 6 subunit (Sonnenberg, A., H. Janssen, F. Hogervorst, J. Calafat, and J. Hilgers. 1987. J. Biol. Chem. 262:10376-10383) specifically inhibited adhesion to laminin-coated surfaces. This antibody precipitated an alpha 6 beta 1 heterodimer (Mr 130/110 kD) from 125I surface-labeled macrophages. The amount of radiolabeled receptor on the cell surface did not increase after PMA activation. Thus, the induction of laminin adhesion cannot be attributed to de novo or increased surface expression of alpha 6 beta 1. By initially removing the Triton X-100-soluble fraction of macrophages and then disrupting the remaining cytoskeletal framework, we observed that 75% of the alpha 6 beta 1 heterodimer on the cell surface is anchored to the cytoskeleton in macrophages that had adhered to a laminin substratum in response to PMA. Significant cytoskeletal anchoring of this receptor was not observed in macrophages that had adhered to fibronectin or tissue culture plastic, nor was it seen in nonadherent cells. PMA also induced phosphorylation of the cytoplasmic domain of the alpha 6 subunit, but not the beta 1 subunit. Phosphorylated alpha 6 was localized to the cytoskeletal fraction only in macrophages plated on a laminin substratum. In summary, our results support a mechanism for the regulation of macrophage adhesion to laminin that involves specific and dynamic matrix integrin-cytoskeletal interactions that may be facilitated by integrin phosphorylation.
Publication
Journal: American Journal of Psychiatry
August/29/2011
Abstract
OBJECTIVE
Two antidepressant medication combinations were compared with selective serotonin reuptake inhibitor monotherapy to determine whether either combination produced a higher remission rate in first-step acute-phase (12 weeks) and long-term (7 months) treatment.
METHODS
The single-blind, prospective, randomized trial enrolled 665 outpatients at six primary and nine psychiatric care sites. Participants had at least moderately severe nonpsychotic chronic and/or recurrent major depressive disorder. Escitalopram (up to 20 mg/day) plus placebo, sustained-release bupropion (up to 400 mg/day) plus escitalopram (up to 20 mg/day), or extended-release venlafaxine (up to 300 mg/day) plus mirtazapine (up to 45 mg/day) was delivered (1:1:1 ratio) by using measurement-based care. The primary outcome was remission, defined as ratings of less than 8 and less than 6 on the last two consecutive applications of the 16-item Quick Inventory of Depressive Symptomatology--Self-Report. Secondary outcomes included side effect burden, adverse events, quality of life, functioning, and attrition.
RESULTS
Remission and response rates and most secondary outcomes were not different among treatment groups at 12 weeks. The remission rates were 38.8% for escitalopram-placebo, 38.9% for bupropion-escitalopram, and 37.7% for venlafaxine-mirtazapine, and the response rates were 51.6%-52.4%. The mean number of worsening adverse events was higher for venlafaxine-mirtazapine (5.7) than for escitalopram-placebo (4.7). At 7 months, remission rates (41.8%-46.6%), response rates (57.4%-59.4%), and most secondary outcomes were not significantly different.
CONCLUSIONS
Neither medication combination outperformed monotherapy. The combination of extended-release venlafaxine plus mirtazapine may have a greater risk of adverse events.
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