144 research outputs found
Inflammatory Biomarker of Peripheral CRP and Analyzing Serum Trace Elements like Zinc, Copper, and Cu to Zn Ratios in Stable Chronic Obstructive Pulmonary Disease: Tehran-Iran
Background: Chronic Obstructive Pulmonary Disease (COPD) is characterized with incomplete airway reversibility by spirometric testing, chronic local airway and systemic inflammation. COPD is the most common lung disease related to smoking habit in general population. Oxidative stress (Os) is the key mechanism in inducing and progression of inflammatory productions in COPD pathogenesis. However, CRP is a peripheral biomarker to reflect systemic inflammation and tissue damage. Nutritional trace elements like Zinc (Zn) and Copper (Cu) are components of Os mechanism and as the anti-oxidant elements. Those changing serum levels influence on the reaction of recent process and production of inflammatory protein. Propose of the study was to evaluate status of CRP and Zn, Cu, Cu/Zn ratios among male patients with stable Chronic Obstructive Pulmonary Disease. Method: Stable COPD patients substantially were enrolled from pulmonary chest medicine. Applying criteria followed an instruction of thoracic society. Results: A total of 35 patients completed criteria of study. Mean age±SD was 52.8±5years (ranged 43-60). Hypozincemia and hypocupremia were found 11% and 14%, respectively. Conclusion: Increased CRP levels reflected presence systemic and pulmonary inflammation among stable COPD patients. In addition, Zinc and copper deficiency detected among target population. The current trace elements are a part of oxidative stress, and their deficiencies may be effective in the induction of inflammation
Frequency of Specific Immunoglobulin G Antibodies and Immediate Skin Test Reactivity to Aspergillus fumigatus Antigen among Adults with Allergic Asthma: Tehran
Background: The Aspergillus fumigatus (AF) has been found the most common etiologic agent in allergic aspergillosis. In addition, AF is responsible for 90% of human infections. Increasing the air pollution in urban area causes the increase in asthma rates. Significant cutaneous sensitization occurs in asthmatic population with AF. In these patients, susceptibility of diseases increases. The aims of this study were to identify frequency of specific IgG antibodies and sensitization to Aspergillus antigens through skin prick-test reactivity (SPT) among adults with allergic asthma and to diagnose atopic phenotype subset. Method: 201 chronic asthmatic patients were applied in order to instructions based on the increased level of immunoglobulin E antibodies concentrations in allergy, having criteria of the study and specific immunoglobulin G antibodies against AF in serum and SPT reactivity with aspergillus antigen. Thereafter, atopic phenotype was diagnosed. Results: 42 (21%) subjects had positive skin reactivity to aspergillus antigens, also specific AF IgG antibodies was observed in 122 (61%). 36 (30%) of positive aspergillus skin prick test was found among those who were positive specific AF IgG antibodies of allergic asthma (P=0.001), 81 (40%) subjects of all allergic asthma patients were atopic. 19 (24%) of the atopic subsets had positive aspergillus skin prick test and specific AF IgG antibodies was seen in 41 (50%) of atopic subjects. In addition, significant differences in aspergillus skin prick test was observed between atopic with nonatopic subgroups (P=0.01). Conclusion: Our finding indicated that significant frequency of specific IgG antibodies seroconvertion against AF in serum and immediate SPT sensitization to AF antigen were detected among chronic bronchial asthma with allergic and also, atopic phenotype subsets
On the Properties of Two Pulses Propagating Simultaneously in Different Dispersion Regimes in a Nonlinear Planar Waveguide
Properties of two pulses propagating simultaneously in different dispersion
regimes, anomalous and normal, in a Kerr-type planar waveguide are studied in
the framework of the nonlinear Schroedinger equation. Catastrophic
self-focusing and spatio-temporal splitting of the pulses is investigated. For
the limiting case when the dispersive term of the pulse propagating in the
normal dispersion regime can be neglected an indication of a possibility of a
stable self-trapped propagation of both pulses is obtained.Comment: 18 pages (including 15 eps figures
Increased Medial Temporal Tau Positron Emission Tomography Uptake in the Absence of Amyloid-β Positivity
IMPORTANCE: An increased tau positron emission tomography (PET) signal in the medial temporal lobe (MTL) has been observed in older individuals in the absence of amyloid-β (Aβ) pathology. Little is known about the longitudinal course of this condition, and its association with Alzheimer disease (AD) remains unclear. OBJECTIVE: To study the pathologic and clinical course of older individuals with PET-evidenced MTL tau deposition (TMTL+) in the absence of Aβ pathology (A-), and the association of this condition with the AD continuum. DESIGN, SETTING, AND PARTICIPANTS: A multicentric, observational, longitudinal cohort study was conducted using pooled data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), Harvard Aging Brain Study (HABS), and the AVID-A05 study, collected between July 2, 2015, and August 23, 2021. Participants in the ADNI, HABS, and AVID-A05 studies (N = 1093) with varying degrees of cognitive performance were deemed eligible if they had available tau PET, Aβ PET, and magnetic resonance imaging scans at baseline. Of these, 128 participants did not meet inclusion criteria based on Aβ PET and tau PET biomarker profiles (A+ TMTL-). EXPOSURES: Tau and Aβ PET, magnetic resonance imaging, cerebrospinal fluid biomarkers, and cognitive assessments. MAIN OUTCOMES AND MEASURES: Cross-sectional and longitudinal measures for tau and Aβ PET, cortical atrophy, cognitive scores, and core AD cerebrospinal fluid biomarkers (Aβ42/40 and tau phosphorylated at threonine 181 p-tau181 available in a subset). RESULTS: Among the 965 individuals included in the study, 503 were women (52.1%) and the mean (SD) age was 73.9 (8.1) years. A total of 51% of A- individuals and 78% of A+ participants had increased tau PET signal in the entorhinal cortex (TMTL+) compared with healthy younger (aged <39 years) controls. Compared with A- TMTL-, A- TMTL+ participants showed statistically significant, albeit moderate, longitudinal (mean [SD], 1.83 [0.84] years) tau PET increases that were largely limited to the temporal lobe, whereas those with A+ TMTL+ showed faster and more cortically widespread tau PET increases. In contrast to participants with A+ TMTL+, those with A- TMTL+ did not show any noticeable Aβ accumulation over follow-up (mean [SD], 2.36 [0.76] years). Complementary cerebrospinal fluid analysis confirmed longitudinal p-tau181 increases in A- TMTL+ in the absence of increased Aβ accumulation. Participants with A- TMTL+ had accelerated MTL atrophy, whereas those with A+ TMTL+ showed accelerated atrophy in widespread temporoparietal brain regions. Increased MTL tau PET uptake in A- individuals was associated with cognitive decline, but at a significantly slower rate compared with A+ TMTL+. CONCLUSIONS AND RELEVANCE: In this study, individuals with A- TMTL+ exhibited progressive tau accumulation and neurodegeneration, but these processes were comparably slow, remained largely restricted to the MTL, were associated with only subtle changes in global cognitive performance, and were not accompanied by detectable accumulation of Aβ biomarkers. These data suggest that individuals with A- TMTL+ are not on a pathologic trajectory toward AD
Instabilities of Higher-Order Parametric Solitons. Filamentation versus Coalescence
We investigate stability and dynamics of higher-order solitary waves in
quadratic media, which have a central peak and one or more surrounding rings.
We show existence of two qualitatively different behaviours. For positive phase
mismatch the rings break up into filaments which move radially to initial ring.
For sufficient negative mismatches rings are found to coalesce with central
peak, forming a single oscillating filament.Comment: 5 pages, 7 figure
Sunscreens - Which and what for?
It is well established that sun exposure is the main cause for the development of skin cancer. Chronic continuous UV radiation is believed to induce malignant melanoma, whereas intermittent high-dose UV exposure contributes to the occurrence of actinic keratosis as precursor lesions of squamous cell carcinoma as well as basal cell carcinoma. Not only photocarcinogenesis but also the mechanisms of photoaging have recently become apparent. In this respect the use of sunscreens seemed to prove to be more and more important and popular within the last decades. However, there is still inconsistency about the usefulness of sunscreens. Several studies show that inadequate use and incomplete UV spectrum efficacy may compromise protection more than previously expected. The sunscreen market is crowded by numerous products. Inorganic sunscreens such as zinc oxide and titanium oxide have a wide spectral range of activity compared to most of the organic sunscreen products. It is not uncommon for organic sunscreens to cause photocontact allergy, but their cosmetic acceptability is still superior to the one given by inorganic sunscreens. Recently, modern galenic approaches such as micronization and encapsulation allow the development of high-quality inorganic sunscreens. The potential systemic toxicity of organic sunscreens has lately primarily been discussed controversially in public, and several studies show contradictory results. Although a matter of debate, at present the sun protection factor (SPF) is the most reliable information for the consumer as a measure of sunscreen filter efficacy. In this context additional tests have been introduced for the evaluation of not only the protective effect against erythema but also protection against UV-induced immunological and mutational effects. Recently, combinations of UV filters with agents active in DNA repair have been introduced in order to improve photoprotection. This article reviews the efficacy of sunscreens in the prevention of epithelial and nonepithelial skin cancer, the effect on immunosuppression and the value of the SPF as well as new developments on the sunscreen market. Copyright (C) 2005 S. Karger AG, Basel
Sensitive electrochemical determination of yohimbine in primary bark of natural aphrodisiacs using boron-doped diamond electrode
For the first time, a simple and sensitive analytical method for the direct determination of yohimbine is presented using differential pulse voltammetry with a boron-doped diamond electrode. Two irreversible oxidation peaks, a distinct one at +0.80 and a second poorly-defined one at +1.65 V, were observed when cyclic voltammetry was carried out in Britton-Robinson buffer solution at pH 7 (vs. Ag/AgCl). With optimized differential pulse voltammetric parameters (pulse amplitude 100 mV, pulse time 25 ms, step potential 5 mV and scan rate 10 mV s(-1)), the current response of yohimbine at +0.80 V was linearly proportional to the concentration in the range from 0.25 to 90.9 mu mol L-1 with a low detection limit of 0.13 mu mol L-1 (0.046 mg L-1) and a good repeatability (relative standard deviation of 2.5% at 18.4 mu mol L-1 for n = 6). The practical applicability of the developed method was demonstrated by the assessment of the total content of yohimbine in extracts of the primary bark of natural aphrodisiacs such as Pausinystalia yohimbe and Rauvolfia serpentina with recoveries in the range of 92-97%. The proposed electrochemical procedure represents an inexpensive and effective analytical alternative for the quality control analysis of products containing yohimbine and other biologically and structurally related alkaloids used as natural dietary supplements
Modulation of host cell processes by T3SS effectors
Two of the enteric Escherichia coli pathotypes-enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC)-have a conserved type 3 secretion system which is essential for virulence. The T3SS is used to translocate between 25 and 50 bacterial proteins directly into the host cytosol where they manipulate a variety of host cell processes to establish a successful infection. In this chapter, we discuss effectors from EPEC/EHEC in the context of the host proteins and processes that they target-the actin cytoskeleton, small guanosine triphosphatases and innate immune signalling pathways that regulate inflammation and cell death. Many of these translocated proteins have been extensively characterised, which has helped obtain insights into the mechanisms of pathogenesis of these bacteria and also understand the host pathways they target in more detail. With increasing knowledge of the positive and negative regulation of host signalling pathways by different effectors, a future challenge is to investigate how the specific effector repertoire of each strain cooperates over the course of an infection
Insulin-like growth factor 1 receptor activation promotes mammary gland tumor development by increasing glycolysis and promoting biomass production
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