470 research outputs found
An Sp1/KLF binding site is important for the activity of a Polycomb group response element from the Drosophila engrailed gene
Polycomb-group response elements (PREs) are DNA elements through which the Polycomb-group (PcG) of transcriptional repressors act. Many of the PcG proteins are associated with two protein complexes that repress gene expression by modifying chromatin. Both of these protein complexes specifically associate with PREs in vivo, however, it is not known how they are recruited or held at the PRE. PREs are complex elements, made up of binding sites for many proteins. Our laboratory has been working to define all the sequences and DNA binding proteins required for the activity of a 181 bp PRE from the Drosophila engrailed gene. Here we show that one of the sites necessary for PRE activity, Site 2, can be bound by members of the Sp1/KLF family of zinc finger proteins. There are 10 Sp1/KLF family members in Drosophila, and nine of them bind to Site 2. We derive a consensus binding site for the Sp1/KLF Drosophila family members and show that this consensus sequence is present in most of the molecularly characterized PREs. These data suggest that one or more Sp1/KLF family members play a role in PRE function in Drosophila
Characterization of the Myocardial Inflammatory Response in Acute Stress-Induced (Takotsubo) Cardiomyopathy
This work was supported by grants from NHS Grampian Endowments and British Heart Foundation Project Grant no. PG/15/108/31928 The authors have reported that they have no relationships relevant to the contents of this paper to disclose.Peer reviewedPublisher PD
Functional improvements associated with upper extremity motor stimulation in individuals with Parkinson's disease
Sherpa Romeo green journal. Open access article. Creative Commons Attribution License (CC BY) appliesBackground: While traditional neurotherapy promotes motor function in people living with Parkinson’s disease (PD), the benefits may be limited by compounding physical, cognitive, and attentional barriers. Since the nontraditional exercise of ice-skating is proving to positively influence motor function and postural control, the purpose of this study was to explore whether the addition of an upper body sensory-driven motor coordination task (stickhandling) would provide upper extremity neuromotor benefit among people with moderate PD. Methods: Seven non-PD control (CTRL) and 22 PD (14 ON-ICE, 8 OFF-ICE) participants completed three trials of a reaching-to-eat (fine motor) task and a button-push (gross motor) task, PRE-and POST-completion of two dynamic – either on- or off-ice – stickhandling tasks. Reaching-to-eat and button-push scores were compared between time periods (PRE, POST) and groups (CTRL, PD ON-ICE, PD OFF-ICE). Results: CTRL participants demonstrated higher scores when compared to the PD groups. Both PD groups demonstrated an improvement in reaching-to-eat and button-push scores immediately following the intervention. Conclusions: These findings suggest that sport-derived exercise programs may provide neuromotor benefit to people living with PD.Ye
Binding of Hyaluronan to the Native Lymphatic Vessel Endothelial Receptor LYVE-1 Is Critically Dependent on Receptor Clustering and Hyaluronan Organization
The lymphatic endothelial receptor LYVE-1 has been implicated in both uptake of hyaluronan (HA) from tissue matrix and in facilitating transit of leukocytes and tumor cells through lymphatic vessels based largely on in vitro studies with recombinant receptor in transfected fibroblasts. Curiously, however, LYVE-1 in lymphatic endothelium displays little if any binding to HA in vitro, and this has led to the conclusion that the native receptor is functionally silenced, a feature that is difficult to reconcile with its proposed in vivo functions. Nonetheless, as we reported recently, LYVE-1 can function as a receptor for HA-encapsulated Group A streptococci and mediate lymphatic dissemination in mice. Here we resolve these paradoxical findings and show that the capacity of LYVE-1 to bind HA is strictly dependent on avidity, demanding appropriate receptor self-association and/or HA multimerization. In particular, we demonstrate the prerequisite of a critical LYVE-1 threshold density and show that HA binding may be elicited in lymphatic endothelium by surface clustering with divalent LYVE-1 mAbs. In addition, we show that cross-linking of biotinylated HA in streptavidin multimers or supramolecular complexes with the inflammation-induced protein TSG-6 enables binding even in the absence of LYVE-1 cross-linking. Finally, we show that endogenous HA on the surface of macrophages can engage LYVE-1, facilitating their adhesion and transit across lymphatic endothelium. These results reveal LYVE-1 as a low affinity receptor tuned to discriminate between different HA configurations through avidity and establish a new mechanistic basis for the functions ascribed to LYVE-1 in matrix HA binding and leukocyte trafficking in vivo
Cancer incidence in HIV-infected versus uninfected veterans: Comparison of cancer registry and ICD-9 code diagnoses
Background: Given the growing interest in the cancer burden in persons living with HIV/AIDS, we examined the validity of data sources for cancer diagnoses (cancer registry versus International Classification of Diseases, Ninth Revision [ICD-9 codes]) and compared the association between HIV status and cancer risk using each data source in the Veterans Aging Cohort Study (VACS), a prospective cohort of HIV-infected and uninfected veterans from 1996 to 2008.
Methods: We reviewed charts to confirm potential incident cancers at four VACS sites. In the entire cohort, we calculated cancer-type-specific age-, sex-, race/ethnicity-, and calendar-period-standardized incidence rates and incidence rate ratios (IRR) (HIV-infected versus uninfected). We calculated standardized incidence ratios (SIR) to compare VACS and Surveillance, Epidemiology, and End Results rates.
Results: Compared to chart review, both Veterans Affairs Central Cancer Registry (VACCR) and ICD-9 diagnoses had approximately 90% sensitivity; however, VACCR had higher positive predictive value (96% versus 63%). There were 6,010 VACCR and 13,386 ICD-9 incident cancers among 116,072 veterans. Although ICD-9 rates tended to be double VACCR rates, most IRRs were in the same direction and of similar magnitude, regardless of data source. Using source, all cancers combined, most viral-infection-related cancers, lung cancer, melanoma, and leukemia had significantly elevated IRRs. Using ICD-9, eight additional IRRs were significantly elevated, most likely due to false positive diagnoses. Most ICD-9 SIRs were significantly elevated and all were higher than the corresponding VACCR SIR.
Conclusions: ICD-9 may be used with caution for estimating IRRs, but should be avoided when estimating incidence or SIRs. Elevated cancer risk based on VACCR diagnoses among HIV-infected veterans was consistent with other studies
Report of the Working Group on Animal Distress in the Laboratory
Finding ways to minimize pain and distress in research animals is a continuing goal in the laboratory animal research field. Pain and distress, however, are not synonymous, and often measures that alleviate one do not affect the other. Here, the authors provide a summary of a meeting held in February 2004 that focused on distress in laboratory animals. They discuss the difficulties associated with defining ‘distress,’ propose methods to aid in recognizing and alleviating distressful conditions, and provide recommendations for animal research conduct and oversight that would minimize distress experienced by laboratory animals
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HIV RNA, CD4+ Percentage, and Risk of Hepatocellular Carcinoma by Cirrhosis Status.
BackgroundDespite increasing incidence of hepatocellular carcinoma (HCC) among HIV-infected patients, it remains unclear if HIV-related factors contribute to development of HCC. We examined if higher or prolonged HIV viremia and lower CD4+ cell percentage were associated with HCC.MethodsWe conducted a cohort study of HIV-infected individuals who had HIV RNA, CD4+, and CD8+ cell counts and percentages assessed in the Veterans Aging Cohort Study (1999-2015). HCC was ascertained using Veterans Health Administration cancer registries and electronic records. Cox regression was used to determine hazard ratios (HR, 95% confidence interval [CI]) of HCC associated with higher current HIV RNA, longer duration of detectable HIV viremia (≥500 copies/mL), and current CD4+ cell percentage less than 14%, adjusting for traditional HCC risk factors. Analyses were stratified by previously validated diagnoses of cirrhosis prior to start of follow-up.ResultsAmong 35 659 HIV-infected patients, 302 (0.8%) developed HCC over 281 441 person-years (incidence rate = 107.3 per 100 000 person-years). Among patients without baseline cirrhosis, higher HIV RNA (HR = 1.25, 95% CI = 1.12 to 1.40, per 1.0 log10 copies/mL) and 12 or more months of detectable HIV (HR = 1.47, 95% CI = 1.02 to 2.11) were independently associated with higher risk of HCC. CD4+ percentage less than 14% was not associated with HCC in any model. Hepatitis C coinfection was a statistically significant predictor of HCC regardless of baseline cirrhosis status.ConclusionAmong HIV-infected patients without baseline cirrhosis, higher HIV RNA and longer duration of HIV viremia increased risk of HCC, independent of traditional HCC risk factors. This is the strongest evidence to date that HIV viremia contributes to risk of HCC in this group
Risk of classic Kaposi sarcoma with exposures to plants and soils in Sicily
<p>Abstract</p> <p>Background</p> <p>Ecologic and in vitro studies suggest that exposures to plants or soil may influence risk of Kaposi sarcoma (KS).</p> <p>Methods</p> <p>In a population-based study of Sicily, we analyzed data on contact with 20 plants and residential exposure to 17 soils reported by 122 classic KS cases and 840 sex- and age-matched controls. With 88 KS-associated herpesvirus (KSHV) seropositive controls as the referent group, novel correlates of KS risk were sought, along with factors distinguishing seronegatives, in multinomial logistic regression models that included matching variables and known KS cofactors - smoking, cortisone use, and diabetes history. All plants were summed for cumulative exposure. Factor and cluster analyses were used to obtain scores and groups, respectively. Individual plants and soils in three levels of exposure with <it>P</it><sub>trend </sub>≤ 0.15 were retained in a backward elimination regression model.</p> <p>Results</p> <p>Adjusted for known cofactors, KS was not related to cumulative exposures to 20 plants [per quartile adjusted odds ratio (OR<sub>adj</sub>) 0.96, 95% confidence interval (CI) 0.73 - 1.25, <it>P</it><sub>trend </sub>= 0.87], nor was it related to any factor scores or cluster of plants (<it>P </it>= 0.11 to 0.81). In the elimination regression model, KS risk was associated with five plants (<it>P</it><sub>trend </sub>= 0.02 to 0.10) and with residential exposure to six soils (<it>P</it><sub>trend </sub>= 0.01 to 0.13), including three soils (eutric regosol, chromic/pellic vertisol) used to cultivate durum wheat. None of the KS-associated plants and only one soil was also associated with KSHV serostatus. Diabetes was associated with KSHV seronegativity (OR<sub>adj </sub>4.69, 95% CI 1.97 - 11.17), but the plant and soil associations had little effect on previous findings that KS risk was elevated for diabetics (OR<sub>adj </sub>7.47, 95% CI 3.04 - 18.35) and lower for current and former smokers (OR<sub>adj </sub>0.26 and 0.47, respectively, <it>P</it><sub>trend </sub>= 0.05).</p> <p>Conclusions</p> <p>KS risk was associated with exposure to a few plants and soils, but these may merely be due to chance. Study of the effects of durum wheat, which was previously associated with cKS, may be warranted.</p
Three Novel Pigmentation Mutants Generated by Genome-Wide Random ENU Mutagenesis in the Mouse
Three mutant mice with pigmentation phenotypes were recovered from a genomewide
random mouse chemical mutagenesis study. White toes (Whto; MGI:1861986),
Belly spot and white toes (Bswt; MGI:2152776) and Dark footpads 2 (Dfp2;
MGI:1861991) were identified following visual inspection of progeny from a male
exposed to the point mutagen ethylnitrosourea (ENU). In order to rapidly localize
the causative mutations, genome-wide linkage scans were performed on pooled
DNA samples from backcross animals for each mutant line. Whto was mapped to
proximal mouse chromosome (Mmu) 7 between Cen (the centromere) and D7Mit112
(8.0 cM from the centromere), Bswt was mapped to centric Mmul between D1Mit214
(32.1 cM) and D1Mit480 (32.8 cM) and Dfp2 was mapped to proximalMmu4 between
Cen and D4Mit18 (5.2 cM). Whto, Bswt and Dfp2 may provide novel starting
points in furthering the elucidation of genetic and biochemical pathways relevant
to pigmentation and associated biological processes
No association between the common calcium-sensing receptor polymorphism rs1801725 and irritable bowel syndrome
Background
The calcium-sensing receptor (CaSR) is a calcium (Ca2+) sensitive G protein-coupled receptor implicated in various biological processes. In particular, it regulates Ca2+/Mg2+- homeostasis and senses interstitial Ca2+ levels and thereby controls downstream signalling cascades. Due to its expression in the gut epithelium, the enteric nervous system and smooth muscles and its key function in regulation and coordination of muscular contraction and secretion, it represents an excellent candidate gene to be investigated in the pathophysiology of irritable bowel syndrome (IBS). Disturbed CaSR structure and function may impact gastrointestinal regulation of muscular contraction, neuronal excitation and secretion and consequently contribute to symptoms seen in IBS, such as disordered defecation as well as disturbed gut motility and visceral sensitivity.
Methods
We have therefore genotyped the functional CASR SNP rs1801725 in three case control samples from the UK, Belgium and the USA.
Results
Genotype frequencies showed no association in the three genotyped case–control samples, neither with IBS nor with IBS subtypes.
Conclusions
Although we could not associate the SNP to any of the established bowel symptom based IBS subtypes we cannot rule out association to altered Ca2+ levels and disturbed secretion and gut motility which were unfortunately not assessed in the patients genotyped. This underlines the necessity of a more detailed phenotyping of IBS patients and control individuals in future studies
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