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Publication
Journal: Genes and Development
June/27/2006
Abstract
Cells often fine-tune gene expression at the level of transcription to generate the appropriate response to a given environmental or developmental stimulus. Both positive and negative influences on gene expression must be balanced to produce the correct level of mRNA synthesis. To this end, the cell uses several classes of regulatory coactivator complexes including two central players, TFIID and Mediator (MED), in potentiating activated transcription. Both of these complexes integrate activator signals and convey them to the basal apparatus. Interestingly, many promoters require both regulatory complexes, although at first glance they may seem to be redundant. Here we have used RNA interference (RNAi) in Drosophila cells to selectively deplete subunits of the MED and TFIID complexes to dissect the contribution of each of these complexes in modulating activated transcription. We exploited the robust response of the metallothionein genes to heavy metal as a model for transcriptional activation by analyzing direct factor recruitment in both heterogeneous cell populations and at the single-cell level. Intriguingly, we find that MED and TFIID interact functionally to modulate transcriptional response to metal. The metal response element-binding transcription factor-1 (MTF-1) recruits TFIID, which then binds promoter DNA, setting up a "checkpoint complex" for the initiation of transcription that is subsequently activated upon recruitment of the MED complex. The appropriate expression level of the endogenous metallothionein genes is achieved only when the activities of these two coactivators are balanced. Surprisingly, we find that the same activator (MTF-1) requires different coactivator subunits depending on the context of the core promoter. Finally, we find that the stability of multi-subunit coactivator complexes can be compromised by loss of a single subunit, underscoring the potential for combinatorial control of transcription activation.
Publication
Journal: Clinical Science
August/3/2006
Abstract
DM (diabetes mellitus) is a metabolic disorder of either absolute or relative insulin deficiency. Optimized insulin injections remain the mainstay life-sustaining therapy for patients with T1DM (Type I DM) in 2006; however, a small subset of patients with T1DM (approx. 10%) are exquisitely sensitive to insulin and lack counter-regulatory measures, putting them at higher risk of neuroglycopenia. One alternative strategy to injected insulin therapy is pancreatic islet transplantation. Islet transplantation came of age when Paul E. Lacy successfully reversed chemical diabetes in rodent models in 1972. In a landmark study published in 2000, Shapiro et al. [A. M. Shapiro, J. R. Lakey, E. A. Ryan, G. S. Korbutt, E. Toth, G. L. Warnock, N. M. Kneteman and R. V. Rajotte (2000) N. Engl. J. Med. 343, 230-238] reported seven consecutive patients treated with islet transplants under the Edmonton protocol, all of whom maintained insulin independence out to 1 year. Substantial progress has occurred in aspects of pancreas procurement, transportation (using the oxygenated two-layer method) and in islet isolation (with controlled enzymatic perfusion and subsequent digestion in the Ricordi chamber). Clinical protocols to optimize islet survival and function post-transplantation improved dramatically with the introduction of the Edmonton protocol, but it is clear that this approach still has potential limitations. Newer pharmacotherapies and interventions designed to promote islet survival, prevent apoptosis, to promote islet growth and to protect islets in the long run from immunological injury are rapidly approaching clinical trials, and it seems likely that clinical outcomes of islet transplantation will continue to improve at the current exponential pace.
Publication
Journal: Prostate
March/19/2013
Abstract
BACKGROUND
Experimental evidence suggests a role for the β(2) -adrenergic receptor pathway in prostate cancer (PCa). We have investigated the association of β-blocker use with PCa incidence and survival in a Norwegian cohort.
METHODS
Data from the Oslo II study in 2000 (n = 6515) were linked with information from the Cancer Registry of Norway and Statistics Norway. PCa risk and overall- and PCa-specific mortality were analyzed using uni- and multi-variable Cox- and competing risk regression models.
RESULTS
At baseline, 776 men (11.9%) reported using a β-blocker. 212 men (3.3%) were diagnosed with PCa before the survey, leaving 6,303 eligible for incidence analysis. During a median follow-up of 122 months, 448 (7.1%) men were diagnosed with PCa. β-blocker use was not associated with PCa risk [hazard ratio (HR): 1.05, 95% CI: 0.79-1.40]. For all patients (n = 655; including med diagnosed before the survey), β-blocker use was not associated with PCa-specific mortality (HR: 0.55, 95% CI 0.24-1.26, P = 0.16). However, in the subgroup of men planned to receive androgen deprivation therapy (ADT), as reported to the Cancer Registry (n = 263), β-blocker use was associated with reduced PCa-specific mortality (HR: 0.14, 95% CI 0.02-0.85, P = 0.032). No effect on overall mortality was seen (HR, all patients: 0.88, 95% CI 0.56-1.38, P = 0.57). β-blocker use did not appear to affect PSA level, Gleason score, or T-stage at diagnosis; however, these variables were missing for many cases.
CONCLUSIONS
Our findings demonstrate a possible benefit of β-blocker use for men treated with ADT, suggesting the need for investigation in larger cohorts.
Publication
Journal: Breast Cancer Research
April/20/2016
Abstract
BACKGROUND
This study aimed at evaluating the overall survival (OS) gain associated with human epidermal growth factor receptor 2 (HER2)-directed therapies in patients with metastatic breast cancer (mBC).
METHODS
A bibliographic search was conducted in PubMed and Cochrane databases. Only phase III randomized controlled trials (RCTs) including HER2-positive (HER2+) mBC patients were included in this review. OS was defined as time from randomization until the occurrence of death from any cause. Studies have been grouped according to the line of treatment, i.e., first-line or second-line or beyond.
RESULTS
Nineteen RCTs were eligible for inclusion, of which 12 assessed therapies targeting HER2+ mBC in the first-line setting. OS improved from 20.3 months in the first RCT (standard chemotherapy; Slamon et al. (N Engl J Med 344:783-92, 2001)) evaluating HER2-targeting therapies to 48 months in the study of Swain et al. (Lancet Oncol 14:461-71, 2013), with triple combination of pertuzumab, trastuzumab and docetaxel. Seven RCTs evaluated the OS of HER2-targeting therapies in the second-line setting and beyond. The OS in second-line setting improved from 15.3 months (capecitabine; Cameron et al. (Breast Cancer Res Treat 112:533-43, 2008)) to 30.7 months (trastuzumab emtansine; Verma et al. (N Engl J Med 367:1783-91, 2012)). In the third-line setting, the association of lapatinib and trastuzumab has demonstrated to improve OS to 4.5 months compared with lapatinib alone (14 months vs. 9.5 months; Blackwell et al. (J Clin Oncol 30:2585-92, 2012)).
CONCLUSIONS
HER2-directed therapies had an undeniable beneficial impact on the OS of patients with HER2+ mBC. The triple combination of docetaxel, pertuzumab and trastuzumab is associated with a survival extent of more than 4.5 years, compared with a life expectancy of 1.5 years achieved 14 years ago.
Publication
Journal: Computers and biomedical research, an international journal
March/3/1991
Abstract
The objective of this study was to determine the quality of MEDLINE searches done by physicians, physician trainees, and expert searchers (clinicians and librarians). Its design was an analytic survey with independent replication in a setting of self-service online searching from medical wards, an intensive care unit, a coronary care unit, an emergency room, and an ambulatory clinic in a 300-bed teaching hospital. Participating were all M.D. clinical clerks, house, and attending staff responsible for patients in the above settings. Intervention for all participants consisted of a 2-h small group class and 1-h practice session on MEDLINE searching (GRATEFUL MED) before free access to MEDLINE. Search questions from 104 randomly selected novice searches were given to 1 of 13 clinicians with prior search experience and 1 of 3 librarians to run independent searches (triplicated searches). Measurements and main results from these unique citations of the triplicated searches were sent to expert clinicians to rate for relevance (7-point scale). Recall (number of relevant citations retrieved from an individual search divided by the total number of relevant citations from all searches on the same topic) and precision (proportion of relevant citations retrieved in each search) were calculated. Librarians were significantly better than novices for both. Librarians had equivalent recall to, and better precision than, experienced end-users. Unexpectedly, only 20% of relevant citations were retrieved by more than one search of the set of three, with the conclusion that novice searchers on MEDLINE via GRATEFUL MED after brief training have relatively low recall and precision. Recall improves with experience but precision remains suboptimal. Further research is needed to determine the "learning curve," evaluate training interventions, and explore the non-overlapping retrieval of relevant citations by different searchers.
Publication
Journal: Epilepsia
February/4/2009
Abstract
OBJECTIVE
Central nervous system plasticity is essential for normal function, but can also reinforce abnormal network behavior, leading to epilepsy and other disorders. The role of altered ion channel expression in abnormal plasticity has not been thoroughly investigated. Nav1.6 is the most abundantly expressed sodium channel in the nervous system. Because of its distribution in the cell body and axon initial segment, Nav1.6 is crucial for action potential generation. The goal of the present study was to investigate the possible role of changes in Nav1.6 expression in abnormal, activity-dependent plasticity of hippocampal circuits.
METHODS
We studied kindling, a form of abnormal activity-dependent facilitation. We investigated: (1) sodium channel protein expression by immunocytochemistry and sodium channel messenger RNA (mRNA) by in situ hybridization, (2) sodium current by patch clamp recordings, and (3) rate of kindling by analysis of seizure behavior. The initiation, development, and expression of kindling in wild-type mice were compared to Nav1.6 +/-med(tg) mice, which have reduced expression of Nav1.6.
RESULTS
We found that kindling was associated with increased expression of Nav1.6 protein and mRNA, which occurred selectively in hippocampal CA3 neurons. Hippocampal CA3 neurons also showed increased persistent sodium current in kindled animals compared to sham-kindled controls. Conversely, Nav1.6 +/-med(tg) mice resisted the initiation and development of kindling.
CONCLUSIONS
These findings suggest an important mechanism for enhanced excitability, in which Nav1.6 may participate in a self-reinforcing cycle of activity-dependent facilitation in the hippocampus. This mechanism could contribute to both normal hippocampal function and to epilepsy and other common nervous system disorders.
Publication
Journal: Infection and Immunity
September/25/1996
Abstract
Nitric oxide (NO) is associated with functions as diverse as peristalsis, blood flow, neuroendosecretion, visual transduction, smooth muscle relaxation, and microbial killing (H. H. W. H. Schmidt and V. Walter, Cell 78:919-925, 1994). Despite the well-established role of NO in macrophage candidacidal activity (E. Cenci, L. Romani, A. Mancacci, R. Spaccapelo, E. Schiaffella, P. Puccetti, and F. Bistoni, Eur. J. Immunol. 23:1034-1038, 1993; J. Jones-Carson, A. Vazquez-Torres, H. Van der Heide, R. D. Wagner, T. Warner, and E. Balish, Nature Med. 1:552-557, 1995; and A. Vazquez-Torres, J. Jones-Carson, T. Warner, and E. Balish, J. Infect. Dis. 172:192-198, 1995), NO is not directly candidacidal for Candida albicans (A. Vazquez-Torres, J. Jones-Carson, and E. Balish, Infect. Immun. 63:1142-1144, 1995). Because macrophages can produce both NO and superoxide anion (02-), we postulated that peroxynitrite (ONOO-), a product of the dilution-limited reaction of NO and O2-, is the candidacidal molecule of activated macrophages. We now report that ONOO-, in addition to being candidacidal in vitro, is responsible for the candidacidal activity of NO-producing macrophages. ONOO- synthesis by NO-producing macrophages was triggered by two independent mechanisms: one was nonopsonic and dependent on fungal cell wall glucan moieties, and the other was dependent on opsonic antibodies. As we have demonstrated for the pathogenic fungus C. albicans, ONOO- may also be the molecule that enables macrophages to kill other microbes that are resistant to both O2- and NO.
Publication
Journal: Journal of Biological Chemistry
November/7/1991
Abstract
To localize the protease(s) involved in shedding of tumor necrosis factor receptors (TNF-R) from activated neutrophils (PMN) (Porteu, F., and C. Nathan (1990) J. Exp. Med. 172, 599-607), we tested subcellular fractions from PMN for their ability to cause loss of TNF-R from intact cells. Exposure of PMN to sonicated azurophil granules at 37 degrees C resulted in inhibition of 125I-TNF binding; 50% inhibition ensued when PMN were treated for approximately 1 min with azurophil granules equivalent to 2-3 PMN per indicator cell. The TNF-R-degrading activity in azurophil granules were identified as elastase by its sensitivity to diisopropyl fluorophosphate (DFP), alpha 1-antitrypsin and N-methoxysuccinyl-Ala-Ala-Pro-Val chloromethyl ketone (MSAAPV-CK), and by the ability of purified elastase to reproduce the effect of azurophil granules. Elastase preferentially acted on the 75-kDa TNF-R, reducing by 85-96% the binding of 125I-TNF to mononuclear cells expressing predominantly this receptor, while having no effect on endothelial cells expressing almost exclusively the 55-kDa TNF-R. Elastase-treated PMN released a 32-kDa soluble fragment of p75 TNF-R that bound TNF and reacted with anti-TNF-R monoclonal antibodies. In contrast, fMet-Leu-Phe-activated PMN shed a 42-kDa fragment from p75 TNF-R, along with similar amounts of a 28-kDa fragment from p55 TNF-R. Shedding of both TNF-Rs by intact activated PMN was more extensive than shedding caused by elastase and was completely resistant to DFP and MSAAPV-CK. Thus, the TNF-R-releasing activity of azurophil granules is distinct from that operative in intact stimulated PMN and could provide an additional mechanism for the control of cellular responses to TNF at sites of inflammation.
Publication
Journal: Diabetic Medicine
October/10/2001
Abstract
OBJECTIVE
To define the number of people in Tayside, Scotland (population 349 303) with Type 2 diabetes who use metformin, the incidence of contraindications to its continued use in these people and the proportion that discontinued metformin treatment following the development of a contraindication.
METHODS
Retrospective cohort study of the incidence of contraindications to metformin in all patients with Type 2 diabetes using metformin from January 1993 to June 1995. The contraindications of acute myocardial infarction, cardiac failure, renal impairment and chronic liver disease were identified by: the regional diabetes information system, biochemistry database and hospital admissions database and a database of all encashed community prescriptions.
RESULTS
One thousand eight hundred and forty seven subjects (26.3% of those with Type 2 diabetes) redeemed prescriptions for metformin. Of these, 3.5% were admitted with an acute myocardial infarction (71 episodes); 4.2% were admitted with cardiac failure (114 episodes); 21.0% received metformin and loop diuretics for cardiac failure concurrently; 4.8% developed renal impairment; and 2.8% developed chronic liver disease. The development of contraindications rarely resulted in discontinuation of metformin, for example only 17.5% and 25% stopped metformin after admission with acute myocardial infarction and development of renal impairment, respectively. In total, 24.5% of subjects receiving metformin, 6.4% of all people with Type 2 diabetes, had contraindications to its use. There was one episode of lactic acidosis in 4600 patient years.
CONCLUSIONS
This population-based study shows that 24.5% of patients prescribed metformin have contraindications to its use. Development of contraindications rarely results in discontinuation of metformin therapy. Despite this, lactic acidosis remains rare. Diabet. Med. 18, 483-488 (2001)
Publication
Journal: Journal of Cellular Biochemistry
December/13/2005
Abstract
Tumor growth requires the development of new vessels that sprout from pre-existing normal vessels in a process known as "angiogenesis" [Folkman (1971) N Engl J Med 285:1182-1186]. These new vessels arise from local capillaries, arteries, and veins in response to the release of soluble growth factors from the tumor mass, enabling these tumors to grow beyond the diffusion-limited size of approximately 2 mm diameter. Angiostatin, a naturally occurring inhibitor of angiogenesis, was discovered based on its ability to block tumor growth in vivo by inhibiting the formation of new tumor blood vessels [O'Reilly et al. (1994a) Cold Spring Harb Symp Quant Biol 59:471-482]. Angiostatin is a proteolytically derived internal fragment of plasminogen and may contain various members of the five plasminogen "kringle" domains, depending on the exact sites of proteolysis. Different forms of angiostatin have measurably different activities, suggesting that much remains to be elucidated about angiostatin biology. A number of groups have sought to identify the native cell surface binding site(s) for angiostatin, resulting in at least five different binding sites proposed for angiostatin on the surface of endothelial cells (EC). This review will consider the data supporting all of the various reported angiostatin binding sites and will focus particular attention on the angiostatin binding protein identified by our group: F(1)F(O) ATP synthase. There have been several developments in the quest to elucidate the mechanism of action of angiostatin and the regulation of its receptor. The purpose of this review is to describe the highlights of research on the mechanism of action of angiostatin, its' interaction with ATP synthase on the EC surface, modulators of its activity, and issues that should be explored in future research related to angiostatin and other anti-angiogenic agents.
Publication
Journal: International Journal of Cancer
July/25/2001
Abstract
Primitive neuroectodermal tumors (PNETs) represent the most frequent malignant brain tumors in childhood. The majority of these neoplasms occur in the cerebellum and are classified as medulloblastomas (MB). Most PNETs develop sporadically; however, their incidence is highly elevated in patients carrying germline APC gene mutations. The APC gene encodes a central component of the WNT/wingless developmental signaling pathway. It regulates the levels of cytoplasmic beta-catenin protein that plays a central role in neural development and cell proliferation. We analyzed 87 sporadic PNETs and 10 PNET cell lines for mutations of the APC gene and beta-catenin (CTNNB1) gene using single strand conformational polymorphism (SSCP) and sequencing analysis. We examined the mutation cluster region of APC (codons 1255--1641) for germline variants and somatic mutations. The medulloblastoma cell line MHH-MED-2 carried a Glu1317Gln missense germline variant and a sporadic MB sample showed a somatic Pro1319Leu substitution. Mutational analysis of exon 3 of CTNNB1 uncovered 4 PNETs (4.8%) with somatic missense mutations. These mutations caused amino acid substitutions in 3 of 80 medulloblastomas (Ser33Phe, Ser33Cys and Ser37Cys) and 1 of 4 supratentorial PNETs (Gly34Val). All mutations affected GSK-3 beta phosphorylation sites of the degradation targeting box of beta-catenin and resulted in nuclear beta-catenin protein accumulation. Deletions of CTNNB1 were not detected by PCR amplification with primers spanning exons 1--5. Our data indicate that inappropriate activation of the WNT/wingless signaling pathway by mutations of its components may contribute to the pathogenesis of a subset of PNETs.
Publication
Journal: Journal of Medicinal Chemistry
January/21/2002
Abstract
The potency of nucleotide antagonists at P2Y1 receptors was enhanced by replacing the ribose moiety with a constrained carbocyclic ring (Nandanan, et al. J. Med. Chem. 2000, 43, 829-842). We have now synthesized ring-constrained methanocarba analogues (in which a fused cyclopropane moiety constrains the pseudosugar ring) of adenine and uracil nucleotides, the endogenous activators of P2Y receptors. Methanocarba-adenosine 5'-triphosphate (ATP) was fixed in either a Northern (N) or a Southern (S) conformation, as defined in the pseudorotational cycle. (N)-Methanocarba-uridine was prepared from the 1-amino-pseudosugar ring by treatment with beta-ethoxyacryloyl cyanate and cyclization to form the uracil ring. Phosphorylation was carried out at the 5'-hydroxyl group through a multistep process: Reaction with phosphoramidite followed by oxidation provided the 5'-monophosphates, which then were treated with 1,1'-carbonyldiimidazole for condensation with additional phosphate groups. The ability of the analogues to stimulate phospholipase C through activation of turkey P2Y1 or human P2Y1, P2Y2, P2Y4, P2Y6, and P2Y11 receptors stably expressed in astrocytoma cells was measured. At recombinant human P2Y1 and P2Y2 receptors, (N)-methanocarba-ATP was 138- and 41-fold, respectively, more potent than racemic (S)-methanocarba-ATP as an agonist. (N)-methanocarba-ATP activated P2Y11 receptors with a potency similar to ATP. (N)-Methanocarba-uridine 5'-triphosphate (UTP) was equipotent to UTP as an agonist at human P2Y2 receptors and also activated P2Y4 receptors with an EC(50) of 85 nM. (N)-Methanocarba-uridine 5'-diphosphate (UDP) was inactive at the hP2Y6 receptor. The vascular effects of (N)-methanocarba-UTP and (N)-methanocarba-UDP were studied in a model of the rat mesenteric artery. The triphosphate was more potent than UTP in inducing a dilatory P2Y4 response (pEC(50) = 6.1 +/- 0.2), while the diphosphate was inactive as either an agonist or antagonist in a P2Y6 receptor-mediated contractile response. Our results suggest that new nucleotide agonists may be designed on the basis of the (N) conformation that favors selectivity for P2Y1, P2Y2, P2Y4, and P2Y11 receptors.
Publication
Journal: Journal of Medicinal Chemistry
April/12/2000
Abstract
The structure-activity relationships of adenosine-3', 5'-bisphosphates as P2Y(1) receptor antagonists have been explored, revealing the potency-enhancing effects of the N(6)-methyl group and the ability to substitute the ribose moiety (Nandanan et al. J. Med. Chem. 1999, 42, 1625-1638). We have introduced constrained carbocyclic rings (to explore the role of sugar puckering), non-glycosyl bonds to the adenine moiety, and a phosphate group shift. The biological activity of each analogue at P2Y(1) receptors was characterized by measuring its capacity to stimulate phospholipase C in turkey erythrocyte membranes (agonist effect) and to inhibit its stimulation elicited by 30 nM 2-methylthioadenosine-5'-diphosphate (antagonist effect). Addition of the N(6)-methyl group in several cases converted pure agonists to antagonists. A carbocyclic N(6)-methyl-2'-deoxyadenosine bisphosphate analogue was a pure P2Y(1) receptor antagonist and equipotent to the ribose analogue (MRS 2179). In the series of ring-constrained methanocarba derivatives where a fused cyclopropane moiety constrained the pseudosugar ring of the nucleoside to either a Northern (N) or Southern (S) conformation, as defined in the pseudorotational cycle, the 6-NH(2) (N)-analogue was a pure agonist of EC(50) 155 nM and 86-fold more potent than the corresponding (S)-isomer. The 2-chloro-N(6)-methyl-(N)-methanocarba analogue was an antagonist of IC(50) 51.6 nM. Thus, the ribose ring (N)-conformation appeared to be favored in recognition at P2Y(1) receptors. A cyclobutyl analogue was an antagonist with IC(50) of 805 nM, while morpholine ring-containing analogues were nearly inactive. Anhydrohexitol ring-modified bisphosphate derivatives displayed micromolar potency as agonists (6-NH(2)) or antagonists (N(6)-methyl). A molecular model of the energy-minimized structures of the potent antagonists suggested that the two phosphate groups may occupy common regions. The (N)- and (S)-methanocarba agonist analogues were docked into the putative binding site of the previously reported P2Y(1) receptor model.
Publication
Journal: Progress in Histochemistry and Cytochemistry
March/12/2007
Abstract
Since the introduction of the fluorescence-labeled antibody method by Coons et al. [Immunological properties of antibody containing a fluorescent group. Proc Soc Exp Biol Med 47, 200-2002], many immunohistochemical methods have been refined to obtain high sensitivity with low background staining at both light and electron microscopic levels. Heat-induced antigen retrieval (HIAR) reported by Shi et al. in the early 1990s has greatly contributed to immunohistochemical analysis for formalin-fixed and paraffin-embedded (FFPE) materials, particularly in the field of pathology. Although antigen retrieval techniques including enzyme digestion, treatment with protein denaturants and heating have been considered tricky and mysterious techniques, the mechanisms of HIAR have been rapidly elucidated. Heating cleaves crosslinks (methylene bridges) and add methylol groups in formaldehyde-fixed proteins and nucleic acids and extends polypeptides to unmask epitopes hidden in the inner portion of antigens or covered by adjacent macromolecules. In buffers having an appropriate pH and ion concentration, epitopes are exposed without entangling the extended polypeptides during cooling process, since polypeptides may strike a balance between hydrophobic attraction force and electrostatic repulsion force. Recent studies have demonstrated that HIAR is applicable for immunohistochemistry with various kinds of specimens, i.e., FFPE materials, frozen sections, plastic-embedded specimens, and physically fixed tissues at both the light- and electron-microscopic levels, and have suggested that the mechanism of HIAR is common to aldehyde-fixed and aldehyde-unfixed materials. Furthermore, heating has been shown to be effective for flow cytometry, nucleic acid histochemistry (fluorescein in situ hybridization (FISH), in situ hybridization (ISH), and terminal deoxynucleotidyl transferase-mediated nick labeling (TUNEL)), and extraction and analysis of macromolecules in both FFPE archive materials and specimens processed by other procedures. In this article, we review mechanism of HIAR and application of heating in both immunohistochemistry and other histochemical reactions.
Publication
Journal: Neuropsychologia
October/13/1993
Abstract
Groups of patients with idiopathic Parkinson's disease (PD), either medicated or unmedicated, were compared with matched groups of normal controls on a computerised battery of tests designed to investigate spatial working memory, visuospatial recognition memory and learning. The medicated PD patients were subdivided into those with mild and severe clinical disability on the basis of Hoehn and Yahr ratings, thus making three groups of PD patients in all. In a test of spatial recognition memory, a significant impairment was only evident in those PD patients who were medicated and had severe clinical symptoms (Hoehn and Yahr stage III-IV). In contrast, none of the three patient groups were impaired in a complementary test of visual pattern recognition memory. Whilst all three patient groups performed well in a test of simultaneous visual matching to sample, medicated patients (MED PD) with severe clinical symptoms were significantly impaired when a short (0-12 sec) delay was introduced. In a test of paired associates learning requiring both visual pattern and visuospatial memory, deficits in learning and memory were only evident in the severely impaired MED PD group. In contrast, in a test of spatial working memory known to be sensitive to frontal lobe damage, significant impairments were found in both groups of medicated PD patients and particularly in those patients with more severe clinical symptoms. Taken together, the results suggest that there are multiple memory impairments in PD which may differentially depend on the clinical severity of the disease.
Publication
Journal: American journal of medical genetics
December/27/2000
Abstract
Transgenic mice lacking the nuclear orphan transcription factor Nur-related receptor 1 (Nurr1) fail to develop mesencephalic dopamine neurons. There is a highly homologous NURR1 gene in humans (formerly known as NOT) which therefore constitutes a good candidate gene for neurologic and psychiatric disorders with an involvement of the dopamine neuron system, such as Parkinson's disease, schizophrenia, and manic-depression. By direct sequencing of genomic DNA, we found two different missense mutations in the third exon of NURR1 in two schizophrenic patients and another missense mutation in the same exon in an individual with manic-depressive disorder. All three mutations caused a similar reduction of in vitro transcriptional activity of NURR1 dimers of about 30-40%. Neither of these amino acid changes, nor any sequence changes whatsoever, were found in patients with Parkinson's disease or control DNA material of normal populations. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:808-813, 2000.
Publication
Journal: Arthroscopy - Journal of Arthroscopic and Related Surgery
December/29/2013
Abstract
OBJECTIVE
The purpose of this study was to compare the efficacy and safety in a randomized, clinical trial of 3 injections of PRGF-Endoret (BTI Biotechnology Institute, Vitoria, Spain) versus one single intra-articular injection of Durolane hyaluronic acid (HA) (Q-MED AB, Uppsala, Sweden) as a treatment for reducing symptoms in patients with knee osteoarthritis (OA).
METHODS
Ninety-six patients with symptomatic knee OA were randomly assigned to receive PRGF-Endoret (3 injections on a weekly basis) or one infiltration with Durolane HA. The primary outcome measures were a 30% decrease and a 50% decrease in the summed score for the pain, physical function, and stiffness subscales of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Lequesne scores from baseline to weeks 24 and 48. The percentage of OMERACT-OARSI (Outcome Measures for Rheumatology Committee and Osteoarthritis Research Society International Standing Committee for Clinical Trials Response Criteria Initiative) responders was also documented. As secondary outcomes, pain, stiffness, and physical function by use of the WOMAC and the Lequesne score were considered and overall safety of the injection themselves.
RESULTS
The mean age of the patients was 63.6 years. Treatment with PRGF-Endoret was significantly more efficient than treatment with Durolane HA in reducing knee pain and stiffness and improving physical function in patients with knee OA. The rate of response to PRGF-Endoret was significantly higher than the rate of response to HA for all the scores including pain, stiffness, and physical function on the WOMAC, Lequesne index, and OMERACT-OARSI responders at 24 and 48 weeks. Adverse events were mild and evenly distributed between the groups.
CONCLUSIONS
Our findings show that PRGF-Endoret is safe and significantly superior to Durolane HA in primary and secondary efficacy analysis both at 24 and 48 weeks; provides a significant clinical improvement, reducing patients' pain and improving joint stiffness and physical function with respect to basal levels in patients with knee OA; and should be considered in the treatment of patients with knee OA.
Publication
Journal: Journal of Experimental Medicine
January/6/2008
Abstract
Protein kinase C (PKC) beta has been reported (Shinohara, H., T. Yasuda, Y. Aiba, H. Sanjo, M. Hamadate, H. Watarai, H. Sakurai, and T. Kurosaki. 2005. J. Exp. Med. 202:1423-1431; Sommer, K., B. Guo, J.L. Pomerantz, A.D. Bandaranayake, M.E. Moreno-Garcia, Y.L. Ovechkina, and D.J. Rawlings. 2005. Immunity. 23:561-574) to play a crucial role in B cell receptor (BCR)-mediated IkappaB kinase (IKK) activation through phosphorylation of caspase recruitment domain 11, Bimp3 (CARMA1). However, it remains unclear whether this PKCbeta-mediated phosphorylation accounts fully for the activation status of CARMA1, because involvement of other kinases, such as phosphoinositide 3-kinase-dependent kinase 1, has also been suggested. We show that PKCbeta mediates phosphorylation of CARMA1 on Ser668, which in turn is essential for BCR-mediated CARMA1-Bcl10-mucosal-associated lymphoid tissue 1 (MALT1) association and subsequent IKK activation. Our analyses also demonstrate that the downstream kinase IKKbeta contributes to facilitating formation of the complex CARMA1-Bcl10-MALT1 by mediating phosphorylation of CARMA1. Hence, our data suggest that PKCbeta is crucial for initial activation of IKK. The activated IKKbeta does not merely function as an effector enzyme but also modifies the upstream signaling complex through a feedback mechanism, thereby optimizing the strength and duration of the nuclear factor kappaB signal.
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Publication
Journal: Molecular and Cellular Biology
August/28/2003
Abstract
TP73, despite significant homology to TP53, is not a classic tumor suppressor gene, since it exhibits upregulation of nonmutated products in human tumors and lacks a tumor phenotype in p73-deficient mice. We recently reported that an N-terminally truncated isoform, DeltaNp73, is upregulated in breast and gynecological cancers. We further showed that DeltaNp73 is a potent transdominant inhibitor of wild-type p53 and TAp73 in cultured human tumor cells by efficiently counteracting their target gene transactivations, apoptosis, and growth suppression functions (A. I. Zaika et al., J. Exp. Med. 6:765-780, 2002). Although these data strongly suggest oncogenic properties of DeltaNp73, this can only be directly shown in primary cells. We report here that DeltaNp73 confers resistance to spontaneous replicative senescence of primary mouse embryo fibroblasts (MEFs) and immortalizes MEFs at a 1,000-fold-higher frequency than occurs spontaneously. DeltaNp73 cooperates with cMyc and E1A in promoting primary cell proliferation and colony formation and compromises p53-dependent MEF apoptosis. Importantly, DeltaNp73 rescues Ras-induced senescence. Moreover, DeltaNp73 cooperates with oncogenic Ras in transforming primary fibroblasts in vitro and in inducing MEF-derived fibrosarcomas in vivo in nude mice. Wild-type p53 is likely a major target of DeltaNp73 inhibition in primary fibroblasts since deletion of p53 or its requisite upstream activator ARF abrogates the growth-promoting effect of DeltaNp73. Taken together, DeltaNp73 behaves as an oncogene that targets p53 that might explain why DeltaNp73 upregulation may be selected for during tumorigenesis of human cancers.
Publication
Journal: American Journal of Clinical Nutrition
December/22/2010
Abstract
BACKGROUND
The Mediterranean dietary pattern might be a potential tool for the prevention of obesity.
OBJECTIVE
We studied the association between adherence to 6 previously published scores used to assess the adherence to the Mediterranean diet and weight change. We also assessed the risk of relevant weight gain (≥ 5 kg) or the risk of developing overweight or obesity.
METHODS
The study population included 10,376 Spanish men and women who were university graduates (mean age = 38 y) and were followed up for a mean (± SD) of 5.7 ± 2.2 y. Diet was assessed at baseline with a 136-item, previously validated food-frequency questionnaire. Weight was assessed at baseline and biennially during follow-up.
RESULTS
Participants with the lowest adherence (≤ 3 points) to the Mediterranean dietary score (MDS) proposed by Trichopoulou et al (range: 0-9; N Engl J Med 2003;348:2599-608) exhibited the highest average yearly weight gain, whereas participants with the highest (≥ 6 points) adherence exhibited the lowest weight gain (adjusted difference: -0.059 kg/y; 95% CI: -0.111, -0.008 kg/y; P for trend = 0.02). This inverse association was extended to other a priori-defined MDSs. The group with the highest adherence to the MDS also showed the lowest risk of relevant weight gain (≥ 5 kg) during the first 4 y of follow-up (odds ratio: 0.76; 95% CI: 0.64, 0.90).
CONCLUSIONS
Adherence to the Mediterranean dietary pattern is significantly associated with reduced weight gain. This dietary pattern can be recommended to slow down age-related weight gain.
Publication
Journal: Magnetic Resonance in Medicine
January/31/2001
Abstract
The assessment of cerebral interstitial oxygen tension (piO(2)) can provide valuable information regarding cerebrovascular physiology and brain function. Compartment-specific cerebral piO(2) was measured by (19)F NMR following the infusion of an oxygen-sensitive perfluorocarbon directly into the interstitial and ventricular space of the in vivo rat brain. (19)F T(1) measurements were made and cerebral piO(2) were obtained through in vitro calibrations. The effects of graded hyperoxia, hypercapnia, and hypoxia on piO(2) and cerebral blood flow (CBF) were investigated. Under normoxia (arterial pO(2) approximately 120 mm Hg), piO(2) was approximately 30 mm Hg and jugular venous pO(2) was approximately 50 mm Hg. During hyperoxia (arterial pO(2) = 90-300 mm Hg), piO(2) increased linearly with the arterial pO(2). Following hypercapnia (arterial pCO(2) = 20-60 mm Hg), the piO(2) increased sigmoidally with increasing CBF. With hypoxia (arterial pO(2) = 30-40 mm Hg), CBF increased approximately 56% and piO(2) decreased to approximately 15 mm Hg. The hypoxia-induced CBF increase was effective to some extent in compensating for the reduced piO(2). This methodology may prove useful for investigating cerebral piO(2) under pathologically or functionally altered conditions. Magn Reson Med 45:61-70, 2001.
Publication
Journal: Magnetic Resonance in Medicine
June/27/2001
Abstract
Four novel macromolecular MRI contrast agents, all of which had the same chemical composition but different molecular weights, were prepared using generation-3, -4, -5, and -6 polyamidoamine (PAMAM) dendrimers conjugated with a bifunctional diethylenetriaminepentaacetic acid derivative to change the blood retention, tissue perfusion, and excretion. Size-dependent changes in the pharmacokinetics were observed in the biodistribution study. (153)Gd-labeled generation-6 PAMAM-conjugates remained in the blood significantly longer than all of the other preparations (P < 0.001). The increase in blood-to-organ ratio of the preparations was found to correlate with increasing molecular size (P < 0.001). Additionally, 3D-micro MR images and angiography of mice of high quality and detail were obtained using PAMAM-(1B4M-Gd)x as a macro-molecular MRI contrast agent with a 1.5-T clinical MRI instrument. Numerous fine vessels of approximately 200 microm diameter were visualized on subtracted 3D-MR angiographms with G6D-(1B4M-Gd)(192). The quality of the images was sufficient to estimate the microvasculature of cancerous tissue for anti-angiogenesis therapy and to investigate knockout mice. Magn Reson Med 45:454-460, 2001.
Publication
Journal: Journal of Global Infectious Diseases
July/13/2011
Abstract
S. aureus is the major bacterial cause of skin, soft tissue and bone infections, and one of the commonest causes of healthcare-associated bacteremia. Hospital-associated methicillin-resistant S. aureus (MRSA) carriage is associated with an increased risk of infection, morbidity and mortality. Screening of high-risk patients at the time of hospital admission and decolonization has proved to be an important factor in an effort to reduce nosocomial transmission. The electronic database Pub Med was searched for all the articles on "Establishment of MRSA and the emergence of vancomycin-resistant S. aureus (VRSA)." The search included case reports, case series and reviews. All the articles were cross-referenced to search for any more available articles. A total of 88 references were obtained. The studies showed a steady increase in the number of vancomycin-intermediate and vancomycin-resistant S. aureus. Extensive use of vancomycin creates a selective pressure that favors the outgrowth of rare, vancomycin-resistant clones leading to heterogenous vancomycin intermediate S. aureus hVISA clones, and eventually, with continued exposure, to a uniform population of vancomycin-intermediate S. aureus (VISA) clones. However, the criteria for identifying hVISA strains have not been standardized, complicating any determination of their clinical significance and role in treatment failures. The spread of MRSA from the hospital to the community, coupled with the emergence of VISA and VRSA, has become major concern among healthcare providers. Infection-control measures, reliable laboratory screening for resistance, appropriate antibiotic prescribing practices and avoidance of blanket treatment can prevent long-term emergence of resistance.
Publication
Journal: Annals of Surgical Oncology
June/4/2014
Abstract
BACKGROUND
Intraductal papillary mucinous neoplasms (IPMNs) are the most common cystic precursor lesions of invasive pancreatic cancer. The recent identification of activating GNAS mutations at codon 201 in IPMNs is a promising target for early detection and therapy. The purpose of this study was to explore clinicopathological correlates of GNAS mutational status in resected IPMNs.
METHODS
Clinical and pathologic characteristics were retrieved on 54 patients in whom GNAS codon 201 mutational status was previously reported ("historical group", Wu et al. Sci Transl Med 3:92ra66, 2011). In addition, a separate cohort of 32 patients (validation group) was included. After microdissection and DNA extraction, GNAS status was determined in the validation group by pyrosequencing.
RESULTS
GNAS activating mutations were found in 64% of the 32 IPMNs included in the validation group, compared with a previously reported prevalence of 57% in the historical group. Overall, 52 of 86 (61%) of IPMNs demonstrated GNAS mutations in the two studies combined. Analysis of both groups confirmed that demographic characteristics, tumor location, ductal system involvement, focality, size, grade of dysplasia, presence of an associated cancer, and overall survival were not correlated with GNAS mutational status. Stratified by histological subtype, 100% of intestinal type IPMNs demonstrated GNAS mutations compared to 51% of gastric IPMN, 71% of pancreatobiliary IPMNs, and 0% of oncocytic IPMNs.
CONCLUSIONS
GNAS activating mutations can be reliably detected in IPMNs by pyrosequencing. In terms of clinicopathological parameters, only histological subtype was correlated with mutational frequency, with the intestinal phenotype always associated with GNAS mutations.
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