322 research outputs found
Hepatic pathology in mice after continuous inhalation exposure to 1,1,1-trichloroethane
Mice exposed to either 250ppm or 1,000ppm 1,1,1-trichloroethane in air continuously for 14 weeks demonstrated significant changes in the centrilobular hepatocytes for the 1,000ppm group. Moderate liver triglyceride accumulation was evident in the 1,000ppm group and peaked at 40mg/gm of tissue after 7 weeks of exposure. Focal hepatocyte necrosis occurred in 40% of the mice exposed to 1,000ppm for 12 weeks. This necrosis was associated with an acute inflammatory infiltrate and hypertrophy of Kupffer cells. These findings indicate that the pathological alternations observed with 1,1,1-trichloroethane are similar to those observed with dichloromethane except for different time courses of the effects and different degrees of recovery. The toxic effects of 1,1,1-trichloroethane are of a similar type to those produced by carbon tetrachloride but appear much less severe
Case Report: Potential Arsenic Toxicosis Secondary to Herbal Kelp Supplement
CONTEXT: Medicinal use of dietary herbal supplements can cause inadvertent arsenic toxicosis. CASE PRESENTATION: A 54-year-old woman was referred to the University of California, Davis, Occupational Medicine Clinic with a 2-year history of worsening alopecia and memory loss. She also reported having a rash, increasing fatigue, nausea, and vomiting, disabling her to the point where she could no longer work full-time. A thorough exposure history revealed that she took daily kelp supplements. A urine sample showed an arsenic level of 83.6 μg/g creatinine (normal < 50 μg/g creatinine). A sample from her kelp supplements contained 8.5 mg/kg (ppm) arsenic. Within weeks of discontinuing the supplements, her symptoms resolved and arsenic blood and urine levels were undetectable. DISCUSSION: To evaluate the extent of arsenic contamination in commercially available kelp, we analyzed nine samples randomly obtained from local health food stores. Eight of the nine samples showed detectable levels of arsenic higher than the Food and Drug Administration tolerance level of 0.5 to 2 ppm for certain food products. None of the supplements contained information regarding the possibility of contamination with arsenic or other heavy metals. The 1994 Dietary Supplement Health and Education Act (DSHEA) has changed the way dietary herbal therapies are marketed and regulated in the United States. Less regulation of dietary herbal therapies will make inadvertent toxicities a more frequent occurrence. RELEVANCE TO CLINICAL PRACTICE: Clinicians should be aware of the potential for heavy metal toxicity due to chronic use of dietary herbal supplements. Inquiring about use of dietary supplements is an important element of the medical history
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On Visible Homelessness and the Micro-Aesthetics of Public Space
In this article, we investigate the circumstances that have produced the current municipal regulatory approach to homelessness in the City of Melbourne, Victoria, and the ways in which visibly homeless people are policed through a micro-aesthetics of their presence in public space, which involves the monitoring of their bodily demeanour and their physical possessions. Our study contributes to and draws from a range of debates, including studies of the governmental conjunction of poverty and crime, analysis of the co-implication of law and spatiality, research on the criminalisation of homelessness and homeless people, and the burgeoning criminological interest in the significance of the visual field for our understandings of crime and criminality. This article recounts how homelessness, public space and questions of aesthetics have recently coalesced in debates about the regulation of homelessness in the public space of Melbourne’s city centre. It approaches the issues through comparative consideration of genres of municipal management frameworks in other jurisdictions, detailed textual consideration of the Protocol on Homelessness in the City of Melbourne and an empirical study of visible homelessness in the public places of central Melbourne
Nonlinear Parabolic Equations arising in Mathematical Finance
This survey paper is focused on qualitative and numerical analyses of fully
nonlinear partial differential equations of parabolic type arising in financial
mathematics. The main purpose is to review various non-linear extensions of the
classical Black-Scholes theory for pricing financial instruments, as well as
models of stochastic dynamic portfolio optimization leading to the
Hamilton-Jacobi-Bellman (HJB) equation. After suitable transformations, both
problems can be represented by solutions to nonlinear parabolic equations.
Qualitative analysis will be focused on issues concerning the existence and
uniqueness of solutions. In the numerical part we discuss a stable
finite-volume and finite difference schemes for solving fully nonlinear
parabolic equations.Comment: arXiv admin note: substantial text overlap with arXiv:1603.0387
On some nonlinear boundary value problems related to a Black-Scholes model with transaction costs
Mechanism of action of probiotics
The modern diet doesn't provide the required amount of beneficial bacteria. Maintenance of a proper microbial ecology in the host is the main criteria to be met for a healthy growth. Probiotics are one such alternative that are supplemented to the host where by and large species of Lactobacillus, Bifidobacterium and Saccharomyces are considered as main probiotics. The field of probiotics has made stupendous strides though there is no major break through in the identification of their mechanism of action. They exert their activity primarily by strengthening the intestinal barrier and immunomodulation. The main objective of the study was to provide a deep insight into the effect of probiotics against the diseases, their applications and proposed mechanism of action
Randomized controlled trial of live lactobacillus acidophilus plus bifidobacterium bifidum in prophylaxis of diarrhea during radiotherapy in cervical cancer patients
<p>Abstract</p> <p>Background</p> <p>Radiation-induced diarrhea is frequently observed during pelvic radiotherapy. This study was performed to determine the ability of a probiotic containing live lactobacillus acidophilus plus bifidobacterium bifidum to reduce the incidence of radiation-induced diarrhea in locally advanced cervical cancer patients.</p> <p>Methods</p> <p>Patients who were undergoing pelvic radiotherapy concurrent with weekly cisplatin were randomly assigned to a study drug or placebo, in a double-blind study. Diarrhea was graded weekly according the Common Toxicity Criteria (CTC) system. Stool consistency and white and red blood cell count in stool were also assessed. The primary endpoint was to reduce the incidence of diarrhea, defined by a CTC grade 2 or more, and the need for anti-diarrheal medication.</p> <p>Results</p> <p>A total of 63 patients were enrolled. Grade 2 -3 diarrhea was observed in 45% of the placebo group (n = 31) and 9% of the study drug group (n = 32) (p = 0.002). Anti-diarrheal medication use was significantly reduced in the placebo group (p = 0.03). The patients in the study drug group had a significantly improved stool consistency (p < 0.001).</p> <p>Conclusions</p> <p>Live lactobacillus acidophilus plus bifidobacterium bifidum reduced the incidence of radiation-induced diarrhea and the need for anti-diarrheal medication and had a significant benefits on stool consistency.</p
Fourier transform ion cyclotron resonance mass spectrometric detection of small Ca2+-induced conformational changes in the regulatory domain of human cardiac troponin C
AbstractTroponin C (TnC), a calcium-binding protein of the thin filament of muscle, plays a regulatory role in skeletal and cardiac muscle contraction. NMR reveals a small conformational change in the cardiac regulatory N-terminal domain of TnC (cNTnC) on binding of Ca2+ such that the total exposed hydrophobic surface area increases very slightly from 3090 ± 86 Å2 for apo-cNTnC to 3108 ± 71 Å2 for Ca2+-cNTnC. Here, we show that measurement of solvent accessibility for backbone amide protons by means of solution-phase hydrogen/deuterium (H/D) exchange followed by pepsin digestion, high-performance liquid chromatography, and electrospray ionization high-field (9.4 T) Fourier transform Ion cyclotron resonance mass spectrometry is sufficiently sensitive to detect such small ligand binding-induced conformational changes of that protein. The extent of deuterium incorporation increases significantly on binding of Ca2+ for each of four proteolytic segments derived from pepsin digestion of the apo- and Ca2+-saturated forms of cNTnC. The present results demonstrate that H/D exchange monitored by mass spectrometry can be sufficiently sensitive to detect and identify even very small conformational changes in proteins, and should therefore be especially informative for proteins too large (or too insoluble or otherwise intractable) for NMR analysis
Classification and criteria of the limit cases for singular second-order linear equations on time scales
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