1,129 research outputs found
Sarcoidosis of the hypothalamus and pituitary stalk
We report a rare case of sarcoidosis of the hypothalamic and suprasellar region, with clinical course and the magnetic resonance imaging follow-up
A Compromise between Neutrino Masses and Collider Signatures in the Type-II Seesaw Model
A natural extension of the standard gauge
model to accommodate massive neutrinos is to introduce one Higgs triplet and
three right-handed Majorana neutrinos, leading to a neutrino mass
matrix which contains three sub-matrices ,
and . We show that three light Majorana neutrinos (i.e., the mass
eigenstates of , and ) are exactly massless in this
model, if and only if
exactly holds. This no-go theorem implies that small but non-vanishing neutrino
masses may result from a significant but incomplete cancellation between
and terms in the Type-II
seesaw formula, provided three right-handed Majorana neutrinos are of TeV and experimentally detectable at the LHC. We propose three simple
Type-II seesaw scenarios with the flavor symmetry to
interpret the observed neutrino mass spectrum and neutrino mixing pattern. Such
a TeV-scale neutrino model can be tested in two complementary ways: (1)
searching for possible collider signatures of lepton number violation induced
by the right-handed Majorana neutrinos and doubly-charged Higgs particles; and
(2) searching for possible consequences of unitarity violation of the neutrino mixing matrix in the future long-baseline neutrino oscillation
experiments.Comment: RevTeX 19 pages, no figure
An epidemiologic study of early biologic effects of benzene in Chinese workers.
Benzene is a recognized hematotoxin and leukemogen, but its mechanisms of action in humans are still uncertain. To provide insight into these processes, we carried out a cross-sectional study of 44 healthy workers currently exposed to benzene (median 8-hr time-weighted average; 31 ppm), and unexposed controls in Shanghai, China. Here we provide an overview of the study results on peripheral blood cells levels and somatic cell mutation frequency measured by the glycophorin A (GPA) gene loss assay and report on peripheral cytokine levels. All peripheral blood cells levels (i.e., total white blood cells, absolute lymphocyte count, platelets, red blood cells, and hemoglobin) were decreased among exposed workers compared to controls, with the exception of the red blood cell mean corpuscular volume, which was higher among exposed subjects. In contrast, peripheral cytokine levels (interleukin-3, interleukin-6, erythropoietin, granulocyte colony-stimulating factor, tissue necrosis factor-alpha) in a subset of the most highly exposed workers (n = 11) were similar to values in controls (n = 11), suggesting that benzene does not affect these growth factor levels in peripheral blood. The GPA assay measures stem cell or precursor erythroid cell mutations expressed in peripheral red blood cells of MN heterozygous subjects, identifying NN variants, which result from loss of the GPA M allele and duplication of the N allele, and N phi variants, which arise from gene inactivation. The NN (but not N phi) GPA variant cell frequency was elevated in the exposed workers compared with controls (mean +/- SD, 13.9 +/- 8.4 mutants per million cells versus 7.4 +/- 5.2 per million cells, (respectively; p = 0.0002), suggesting that benzene produces gene-duplicating but not gene-inactivating mutations at the GPA locus in bone marrow cells of exposed humans. These findings, combined with ongoing analyses of benzene macromolecular adducts and chromosomal aberrations, will provide an opportunity to comprehensively evaluate a wide range of early biologic effects associated with benzene exposure in humans
Anisotropic Radial Layout for Visualizing Centrality and Structure in Graphs
This paper presents a novel method for layout of undirected graphs, where
nodes (vertices) are constrained to lie on a set of nested, simple, closed
curves. Such a layout is useful to simultaneously display the structural
centrality and vertex distance information for graphs in many domains,
including social networks. Closed curves are a more general constraint than the
previously proposed circles, and afford our method more flexibility to preserve
vertex relationships compared to existing radial layout methods. The proposed
approach modifies the multidimensional scaling (MDS) stress to include the
estimation of a vertex depth or centrality field as well as a term that
penalizes discord between structural centrality of vertices and their alignment
with this carefully estimated field. We also propose a visualization strategy
for the proposed layout and demonstrate its effectiveness using three social
network datasets.Comment: Appears in the Proceedings of the 25th International Symposium on
Graph Drawing and Network Visualization (GD 2017
Altered stress hormone response following acute exercise during prostate cancer treatment
Exercise training reduces the side effects of cancer treatments; however, the stress hormone response to acute exercise during prostate cancer (PCa) treatment is unclear. The study purpose was to examine the effects of acute exercise on circulating cortisol, epinephrine (Epi), and norepinephrine (NE) concentrations during PCa treatment with and without androgen deprivation therapy (ADT). Men with PCa (n = 11), with PCa on ADT (n = 11), and with non-cancer controls (n = 8) had blood samples for stress hormones collected before and immediately (0 hour), 2 hours, and 24 hours after 45 minutes of intermittent cycling at 60% of peak wattage. NE increased by 385% (P < .001) at 0 hour and remained elevated at 2 hours (P < .05) with no group differences. Overall, cortisol significantly increased at 0 hour (36%, P < .012) and then significantly decreased below baseline at 2 hours (-24%, P < .001) before returning to resting levels at 24 hours. Cortisol levels during ADT were 32% lower than PCa (P = .006) with no differences vs controls. Epi increased immediately after exercise more in controls (817%, P < .001) than with ADT (700%) and PCa (333%) patients, and both cancer groups' absolute levels were attenuated relative to controls (ADT: -54%, PCa: -52%, P = .004). Compared with age-matched controls, PCa and ADT patients exhibited similar stress hormone responses with acute exercise for NE and cortisol but an attenuated EPI response that suggests altered adrenal function. Future studies should examine the physical stress of multiple exercise bouts to verify these findings and to explore the functional hormonal effects, such as immune and metabolic responses, during cancer treatment
Association between the mood stabilizing treatment of bipolar disorder and risk of suicide attempts: A self-controlled case series study
Bipolar disorder (BPD) is associated with high rates of suicide attempts but the anti-suicidal effect of mood stabilizing agents remains unclear. This study aimed to examine the association between mood stabilizing agents (lithium, valproate, lamotrigine, carbamazepine or antipsychotics) and risk of suicide attempts in patients with BPD using self-controlled case series study design.
Among 14,087 patients with BPD who received mood stabilizing agents from 2001 to 2020 in Hong Kong, 1316 patients had at least one suicide attempts during the observation period. An increased risk of suicide attempts was observed 14 days before treatment initiation compared to non-exposed period. Following treatment initiation, an increased risk with smaller magnitude was found with the use of mood stabilizing agents. A lower risk was observed with lithium and antiepileptics while the risk remained attenuated with decreasing magnitude with antipsychotics. During 30-day post-treatment period, the risk was elevated. Therefore, this study suggests that use of mood stabilizing agents is not causally associated with an increased risk of suicide attempts. Indeed, there are potential protective effects of lithium and antiepileptics against suicide attempts. Assiduous monitoring of symptoms relapse and warning signs of suicide should be part of the management plan and discussed between clinicians, caregivers and patients
Toxicity of Three Insecticides to Lysiphlebus fabarum, a Parasitoid of the Black Bean Aphid, Aphis fabae
The toxicity of three insecticides to Lysiphlebus fabarum (Marshall) (Hymenoptera: Braconidae: Aphidiinae), a parasitoid of Aphis fabae Scopoli (Hemiptera: Aphididae), was investigated using IOBC/wprs protocols. Abamectin 1.8 EC, imidacloprid 350 SC, and pymetrozine 25 WP were tested under laboratory conditions at recommended field rates. Immature stages of the parasitoid were exposed to materials by briefly dipping mummified aphids into insecticide solutions/suspensions or water (controls). Abamectin, imidacloprid, and pymetrozine caused 44.8, 58.5, and 14.5% mortality of mummies, respectively. Insecticides were also applied to broad bean foliage until run-off using a hand sprayer and the contact toxicity of residues was investigated after 1, 5, 16 and 30 day periods of outdoor weathering by caging adult wasps on treated plants for 24 h. One day-old residues of abamectin, imidacloprid, and pymetrozine produced 52.5, 90.0 and 57.0% mortality, respectively, and 5 day-old residues produced 28.1, 77.0 and 18.6% mortality. Sixteen day-old residues produced 8.8, 22.4 and 13.6% mortality, whereas 30 day-old residues produced 0.0, 3.2 and 1.1% mortality, respectively. On the basis of these results, abamectin and pymetrozine were classified as short-lived compounds (Class A) and imidacloprid as a slightly persistent compound (Class B)
Rationale, design and methods of the Study of Work and Pain (SWAP): a cluster randomised controlled trial testing the addition of a vocational advice service to best current primary care for patients with musculoskeletal pain (ISRCTN 52269669)
Background
Musculoskeletal pain is a major contributor to short and long term work absence. Patients
seek care from their general practitioner (GP) and yet GPs often feel ill-equipped to deal with
work issues. Providing a vocational case management service in primary care, to support
patients with musculoskeletal problems to remain at or return to work, is one potential
solution but requires robust evaluation to test clinical and cost-effectiveness.
Methods/Design
This protocol describes a cluster randomised controlled trial, with linked qualitative
interviews, to investigate the effect of introducing a vocational advice service into general
practice, to provide a structured approach to managing work related issues in primary care
patients with musculoskeletal pain who are absent from work or struggling to remain in work.
General practices (n = 6) will be randomised to offer best current care or best current care
plus a vocational advice service. Adults of working age who are absent from or struggling to
remain in work due to a musculoskeletal pain problem will be invited to participate and 330
participants will be recruited. Data collection will be through patient completed
questionnaires at baseline, 4 and 12 months. The primary outcome is self-reported work
absence at 4 months. Incremental cost-utility analysis will be undertaken to calculate the cost
per additional QALY gained and incremental net benefits. A linked interview study will
explore the experiences of the vocational advice service from the perspectives of GPs, nurse
practitioners (NPs), patients and vocational advisors.
Discussion
This paper presents the rationale, design, and methods of the Study of Work And Pain
(SWAP) trial. The results of this trial will provide evidence to inform primary care practice
and guide the development of services to provide support for musculoskeletal pain patients
with work-related issues.
Trial registration
Current Controlled Trials ISRCTN52269669
Synchronization modulation increases transepithelial potentials in MDCK monolayers through Na/K pumps
Peer reviewedPublisher PD
Clinicoradiological manifestations of paraganglioma syndromes associated with succinyl dehydrogenase enzyme mutation
BACKGROUND: Paragangliomas are rare tumours derived from the autonomic nervous system that have increasingly been recognised to have a genetic predisposition. Mutations of the enzyme succinyl dehydrogenase (SDH) have proven to result in paraganglioma formation. There are four subunits (A through D) that form the enzyme complex and are associated with different genophenotypic expressions of disease. SDHB and SDHD mutations are more common, whereas SDHA and SDHC mutations are rare. Patients with SDHB mutations are prone to extra-adrenal pheochromocytomas, malignant disease and extra-paraganglial neoplasia, whereas SDHD mutations have a greater propensity for multiple, benign head and neck paragangliomas. METHODS: Diagnosis of a sporadic paraganglioma or pheochromocytoma should lead to a full genetic workup of the patient and family if SDH mutations are found. RESULTS: Further annual screening will be required depending on the mutation, which can have a significant impact on radiologists and the resources of the radiology department. CONCLUSION: We present our imaging experience with a series of patients with proven SDH mutations resulting in paragangliomas with a review of the literature
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