962 research outputs found
Three synchronous primary carcinomas in a patient with HNPCC associated with a novel germline mutation in MLH1: Case report
<p>Abstract</p> <p>Background</p> <p><it>MLH1 </it>is one of six known genes responsible for DNA mismatch repair (MMR), whose inactivation leads to HNPCC. It is important to develop genotype-phenotype correlations for HNPCC, as is being done for other hereditary cancer syndromes, in order to guide surveillance and treatment strategies in the future.</p> <p>Case presentation</p> <p>We report a 47 year-old male with hereditary nonpolyposis colorectal cancer (HNPCC) associated with a novel germline mutation in <it>MLH1</it>. This patient expressed a rare and severe phenotype characterized by three synchronous primary carcinomas: ascending and splenic flexure colon adenocarcinomas, and ureteral carcinoma. Ureteral neoplasms in HNPCC are most often associated with mutations in <it>MSH2 </it>and rarely with mutations in <it>MLH1</it>. The reported mutation is a two base pair insertion into exon 10 (c.866_867insCA), which results in a premature stop codon.</p> <p>Conclusion</p> <p>Our case demonstrates that HNPCC patients with <it>MLH1 </it>mutations are also at risk for ureteral neoplasms, and therefore urological surveillance is essential. This case adds to the growing list of disease-causing MMR mutations, and contributes to the development of genotype-phenotype correlations essential for assessing individual cancer risk and tailoring of optimal surveillance strategies. Additionally, our case draws attention to limitations of the Amsterdam Criteria and the need to maintain a high index of suspicion when newly diagnosed colorectal cancer meets the Bethesda Criteria. Establishment of the diagnosis is the crucial first step in initiating appropriate surveillance for colorectal cancer and other HNPCC-associated tumors in at-risk individuals.</p
The enduring culture and limits of political song
The connection between song and politics is well documented, but in recent years is said to be severed. This is not the case. The relationship between politics and song endures, reflecting and revivifying a culture of political struggle. In this essay, I survey political song, outlining how it is approached, before arguing for a tighter definition after working through the claim that all song is political. In doing so, I build a platform for discussion of songs by English singer-songwriter Leon Rosselson. For over 50 years, Rosselson’s songwriting has illuminated historical and topical events from a left-wing perspective, but he is also clear a song converts noone and changes nothing. To think otherwise misunderstands that songs are neither mobilisers or opiates, but an idiom for people to express their everyday lives and struggles. The essay concludes by assessing Rosselson’s insights on the power and limits of song
Blocking Zika virus vertical transmission.
The outbreak of the Zika virus (ZIKV) has been associated with increased incidence of congenital malformations. Although recent efforts have focused on vaccine development, treatments for infected individuals are needed urgently. Sofosbuvir (SOF), an FDA-approved nucleotide analog inhibitor of the Hepatitis C (HCV) RNA-dependent RNA polymerase (RdRp) was recently shown to be protective against ZIKV both in vitro and in vivo. Here, we show that SOF protected human neural progenitor cells (NPC) and 3D neurospheres from ZIKV infection-mediated cell death and importantly restored the antiviral immune response in NPCs. In vivo, SOF treatment post-infection (p.i.) decreased viral burden in an immunodeficient mouse model. Finally, we show for the first time that acute SOF treatment of pregnant dams p.i. was well-tolerated and prevented vertical transmission of the virus to the fetus. Taken together, our data confirmed SOF-mediated sparing of human neural cell types from ZIKV-mediated cell death in vitro and reduced viral burden in vivo in animal models of chronic infection and vertical transmission, strengthening the growing body of evidence for SOF anti-ZIKV activity
The P2Y1 receptor is involved in the maintenance of glucose homeostasis and in insulin secretion in mice
Pancreatic β cells express several P2 receptors including P2Y1 and the modulation of insulin secretion by extracellular nucleotides has suggested that these receptors may contribute to the regulation of glucose homeostasis. To determine whether the P2Y1 receptor is involved in this process, we performed studies in P2Y1 mice. In baseline conditions, P2Y1-mice exhibited a 15% increase in glycemia and a 40% increase in insulinemia, associated with a 10% increase in body weight, pointing to a role of the P2Y1 receptor in the control of glucose metabolism. Dynamic experiments further showed that P2Y1-mice exhibited a tendency to glucose intolerance. These features were associated with a decrease in the plasma levels of free fatty acid and triglycerides. When fed a lipids and sucrose enriched diet for 15 weeks, the two genotypes no longer displayed any significant differences. To determine whether the P2Y1 receptor was directly involved in the control of insulin secretion, experiments were carried out in isolated Langerhans islets. In the presence of high concentrations of glucose, insulin secretion was significantly greater in islets from P2Y1-mice. Altogether, these results show that the P2Y1 receptor plays a physiological role in the maintenance of glucose homeostasis at least in part by regulating insulin secretion
Mott physics and band topology in materials with strong spin-orbit interaction
Recent theory and experiment have revealed that strong spin-orbit coupling
can have dramatic qualitative effects on the band structure of weakly
interacting solids. Indeed, it leads to a distinct phase of matter, the
topological band insulator. In this paper, we consider the combined effects of
spin-orbit coupling and strong electron correlation, and show that the former
has both quantitative and qualitative effects upon the correlation-driven Mott
transition. As a specific example we take Ir-based pyrochlores, where the
subsystem of Ir 5d electrons is known to undergo a Mott transition. At weak
electron-electron interaction, we predict that Ir electrons are in a metallic
phase at weak spin-orbit interaction, and in a topological band insulator phase
at strong spin-orbit interaction. Very generally, we show that with increasing
strength of the electron-electron interaction, the effective spin-orbit
coupling is enhanced, increasing the domain of the topological band insulator.
Furthermore, in our model, we argue that with increasing interactions, the
topological band insulator is transformed into a "topological Mott insulator"
phase, which is characterized by gapless surface spin-only excitations. The
full phase diagram also includes a narrow region of gapless Mott insulator with
a spinon Fermi surface, and a magnetically ordered state at still larger
electron-electron interaction.Comment: 10+ pages including 3+ pages of Supplementary Informatio
Development of a New Nordic Diet score and its association with gestational weight gain and fetal growth – a study performed in the Norwegian Mother and Child Cohort Study (MoBa)
Genetic Analyses in Small for Gestational Age Newborns
Context: Small for gestational age (SGA) can be a result of fetal growth restriction, associated with perinatal morbidity and mortality. Mechanisms that control prenatal growth are poorly understood.
Objective: The aim of the present study was to gain more insight into prenatal growth failure and determine an effective diagnostic approach in SGA newborns. We hypothesized that one or more CNVs and disturbed methylation and sequence variants may be present in genes known to be associated with fetal growth.
Design: A prospective cohort study of subjects with a low birthweight for gestational age.
Setting: The study was conducted at an academic pediatric research institute.
Patients:
A total of 21 SGA newborns with a mean birthweight below the 1st centile and a control cohort of 24 appropriate for gestational age newborns were studied.
Intervention:
Array comparative genomic hybridization, genome-wide methylation studies and exome sequencing were performed.
Main Outcome Measures
The numbers of copy number variations, methylation disturbances and sequence variants.
Results:
The genetic analyses demonstrated three CNVs, one systematically disturbed methylation pattern and one sequence variant explaining the SGA. Additional methylation disturbances and sequence variants were present 20 patients. In 19 patients, multiple abnormalities were found.
Conclusion: Our results confirm the influence of a large number of mechanisms explaining dysregulation of fetal growth. We conclude that copy number variations, methylation disturbances and sequence variants all contribute to prenatal growth failure. Such genetic workup can be an effective diagnostic approach in SGA newborns
Integration of a 3D hydrogel matrix within a hollow core photonic crystal fibre for DNA probe immobilization
In this paper, we demonstrate the integration of a 3D hydrogel matrix within a hollow core photonic crystal fibre (HC-PCF). In addition, we also show the fluorescence of Cy5-labelled DNA molecules immobilized within the hydrogel formed in two different types of HC-PCF. The 3D hydrogel matrix is designed to bind with the amino groups of biomolecules using an appropriate cross-linker, providing higher sensitivity and selectivity than the standard 2D coverage, enabling a greater number of probe molecules to be available per unit area. The HC-PCFs, on the other hand, can be designed to maximize the capture of fluorescence to improve sensitivity and provide longer interaction lengths. This could enable the development of fibre-based point-of-care and remote systems, where the enhanced sensitivity would relax the constraints placed on sources and detectors. In this paper, we will discuss the formation of such polyethylene glycol diacrylate (PEGDA) hydrogels within a HC-PCF, including their optical properties such as light propagation and auto-fluorescence
Empirical Legal Studies Before 1940: A Bibliographic Essay
The modern empirical legal studies movement has well-known antecedents in the law and society and law and economics traditions of the latter half of the 20th century. Less well known is the body of empirical research on legal phenomena from the period prior to World War II. This paper is an extensive bibliographic essay that surveys the English language empirical legal research from approximately 1940 and earlier. The essay is arranged around the themes in the research: criminal justice, civil justice (general studies of civil litigation, auto accident litigation and compensation, divorce, small claims, jurisdiction and procedure, civil juries), debt and bankruptcy, banking, appellate courts, legal needs, legal profession (including legal education), and judicial staffing and selection. Accompanying the essay is an extensive bibliography of research articles, books, and reports
Infection rates associated with epidural indwelling catheters for seven days or longer: systematic review and meta-analysis
BACKGROUND: To determine infection rate with use of epidural catheters in place for seven days or more. METHODS: Systematic review and pooled analysis of observational studies. RESULTS: Twelve studies with 4,628 patients (median 197 patients) provided information, of which nine (4,334 patients) were published after 1990. Eight studies (3,893 patients) were retrospective, and four studies (735 patients) prospective. Electronic searches identified three studies and searching reference lists nine. There were 257 catheter-related infections in total, of which 211 were superficial and 57 deep, giving rates of 6.1%, 4.6% and 1.2% respectively. Ten of the 12 studies had deep infection rates of 2% or less. The incidence of deep infection was 1 per 2391 days of treatment, or 0.4 per 1000 catheter treatment days. In nine studies (1503 patients), predominantly in cancer, and with average catheter duration of 74 days, the deep infection rate was 2.8%. The proportion of patients with infection of any type was higher in cancer patients with longer catheter duration. Limited numbers of events meant that no reliable estimate of the impact of prospective and retrospective design could be made. There appeared to be a relationship between catheter duration and infection rate from this and other recent estimates. Four of 57 (7%) patients with deep infection died. CONCLUSION: The best estimate is that one person in 35 with an epidural catheter in place for 74 days for relief of cancer pain can be expected to have a deep epidural infection, and that about 1 in 500 may die of infection-related causes. This is a most uncertain estimate given the limited nature of the evidence
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