Home About us Contact
|
Home About us Contact | ||
|
|
||
Valuable Method (valuable + method)
Selected AbstractsTopical and systemic photoprotectionDERMATOLOGIC THERAPY, Issue 1 2003Cheryl F. Rosen ABSTRACT: Sunscreens are a valuable method of sun protection. Several new compounds are now available. It is important to remember, however, that photoprotection includes more than the use of sunscreens. There are a number of sun-protective behaviors that people can use to decrease their exposure to ultraviolet (UV) radiation. Dermatologists and other health professionals can work toward changing public policy, greatly increasing the ability of people to access shade. In addition, there is growing evidence about the effectiveness of other sun-protective agents. The only systemic medication for sun protection is ,-carotene, which is effective in erythropoietic protoporphyria (EPP). [source] Cytologic diagnosis of pancreatic endocrine tumors by endoscopic ultrasound-guided fine-needle aspiration: A reviewDIAGNOSTIC CYTOPATHOLOGY, Issue 9 2006Fuju Chang M.D., Ph.D. Abstract Precise localization and diagnosis of pancreatic endocrine tumors (PETs) is important, because pancreatic PETs have different clinical and biological behavior and treatment modalities than do exocrine pancreatic tumors. In contrast to the much more common exocrine adenocarcinomas, cytologic studies of PET are relatively rare and many cytopathologists lack experience with the cytomorphologic features of these tumors. During the last 10 yr, endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) has matured into an accurate, highly sensitive, and cost-effective modality for the preoperative localization of pancreatic PETs. This has resulted in an increased number of PETs first sampled as cytology specimens. This manuscript focuses on the cytomorphologic features most suggestive of pancreatic PETs, differential diagnosis, and diagnostic pitfalls of PETs. The technical development of EUS-guided FNA and the ancillary studies for pancreatic PETs are also reviewed. The data summarized in this review indicate that EUS-FNA is a valuable method in the recognition of pancreatic PETs and in most cases cytopathologists could reach a correct diagnosis of these tumors, including their hormone producing capability on aspirated cytologic material. Diagn. Cytopathol. 2006;34:649,658. © 2006 Wiley-Liss, Inc. [source] A rapid screening test to distinguish between Candida albicans and Candida dubliniensis using NMR spectroscopyFEMS MICROBIOLOGY LETTERS, Issue 2 2005Uwe Himmelreich Abstract Nuclear magnetic resonance (NMR) spectroscopy combined with a statistical classification strategy (SCS) successfully distinguished between Candida albicans and Candida dubliniensis. 96% of the isolates from an independent test set were identified correctly. This proves that this rapid approach is a valuable method for the identification and chemotaxonomic characterisation of closely related taxa. Most discriminatory regions were correlated with metabolite profiles, indicating biochemical differences between the two species. [source] Pharmacokinetic predictions in children by using the physiologically based pharmacokinetic modellingFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 6 2008F. Bouzom Abstract Nowadays, 50,90% of drugs used in children have never been actually studied in this population. Consequently, either our children are often exposed to the risk of adverse drug events or to lack of efficacy, or they are unable to benefit from a number of therapeutic advances offered to adults, as no clinical study has been properly performed in children. Actually the main methods used to calculate the dose for a child are based on allometric methods taking into account different categories of age, the body weight and/or the body surface area. Unfortunately, these calculation methods consider the children as small adults, which is not the case. Physiologically based pharmacokinetics is one way to integrate the physiological changes occurring in the childhood and to anticipate their impact on the pharmacokinetic processes: absorption, distribution, metabolism and excretion/elimination. From different examples, the application of this modelling approach is discussed as a possible and valuable method to minimize the ethical and technical difficulties of conducting research in children. [source] Drug effect on EEG connectivity assessed by linear and nonlinear couplingsHUMAN BRAIN MAPPING, Issue 3 2010Joan F. Alonso Abstract Quantitative analysis of human electroencephalogram (EEG) is a valuable method for evaluating psychopharmacological agents. Although the effects of different drug classes on EEG spectra are already known, interactions between brain locations remain unclear. In this work, cross mutual information function and appropriate surrogate data were applied to assess linear and nonlinear couplings between EEG signals. The main goal was to evaluate the pharmacological effects of alprazolam on brain connectivity during wakefulness in healthy volunteers using a cross-over, placebo-controlled design. Eighty-five pairs of EEG leads were selected for the analysis, and connectivity was evaluated inside anterior, central, and posterior zones of the scalp. Connectivity between these zones and interhemispheric connectivity were also measured. Results showed that alprazolam induced significant changes in EEG connectivity in terms of information transfer in comparison with placebo. Trends were opposite depending on the statistical characteristics: decreases in linear connectivity and increases in nonlinear couplings. These effects were generally spread over the entire scalp. Linear changes were negatively correlated, and nonlinear changes were positively correlated with drug plasma concentrations; the latter showed higher correlation coefficients. The use of both linear and nonlinear approaches revealed the importance of assessing changes in EEG connectivity as this can provide interesting information about psychopharmacological effects. Hum Brain Mapp, 2010. © 2009 Wiley-Liss, Inc. [source] Real-time atomic force microscopy of root dentine during demineralization when subjected to chelating agentsINTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2006G. De-Deus Abstract Aim, To explore the potential of atomic force microscopy (AFM) for the examination of changes to dentine surfaces during demineralization and evaluate qualitatively the effect of EDTA, EDTAC and citric acid. Methodology, Nine canine teeth were sectioned transversely at the cemento-enamel junction, and the crowns discarded. Subsequently, each root was embedded in an epoxy cylinder and discs approximately 5 mm thick were cut. A standard metallographic procedure was then used to prepare the surfaces for observation. From the central portion of these samples, two specimens were symmetrically prepared per tooth so that a total number of 18 samples was produced. To allow the use of a liquid cell during AFM, the samples were embedded in silicone rubber and were then randomly divided into three groups, as follows: group 1: 17% EDTA (pH 7.7), group 2: 17% EDTAC (pH 7.7) and group 3: 10% citric acid (pH 1.4). Topographical images were acquired during the demineralization process, allowing real-time observation of the dentine surface. Two operators assigned scores to the AFM images using a double-blind method. anova analysis with random effects (P < 0.05) was used to compare the results. Results, The average scores were 6.13 ± 0.35 for EDTAC, 7.36 ± 0.23 for EDTA and 14.55 ± 1.21 for citric acid. Citric acid was statistically different from EDTA and EDTAC while EDTA and EDTAC were not statistically different. Conclusions, The most effective demineralizing substance was citric acid. The methodology developed for real-time observation of dentine surfaces is a valuable method to evaluate demineralization. [source] Drug release phenomena within a hydrophobic starch acetate matrix: FTIR mapping of tablets after in vitro dissolution testingJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 8 2008Jari Pajander Abstract The aim of this study was to assess the utility of Fourier transform infrared mapping to study the drug release phenomena within a hydrophobic matrix tablet. Starch acetate with a degree of substitution (2.7) was used as a hydrophobic matrix former. Anhydrous caffeine and riboflavin sodium phosphate were used as water soluble model drugs. The USP (XXVIII) paddle-method was selected as an in vitro dissolution test. Mapping of the diluted tablets' cross-section was performed by attenuated total reflection mode. Fourier transform infrared mapping can distinguish drug particles from the bulk matrix and it can be considered as a valuable method for obtaining both quantitative and qualitative information on drug release processes. The physicochemical properties of the drug compound strongly contribute to its release behavior when the USP paddle in vitro dissolution test is used. Mapping of the riboflavin product revealed a more homogenous matrix distribution due to its smaller particle size. Consequently, its dissolution release profile was more uniform than caffeine which possessed a wider particle size distribution and lower solubility. Mapping showed that caffeine became localized in the lower part of the tablet unlike riboflavin. The hydrodynamic conditions during the in vitro release test might contribute to this differentiation. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97: 3367,3378, 2008 [source] The actual incidence of papaverine-induced priapism in patients with erectile dysfunction following penile colour Doppler ultrasonographyANDROLOGIA, Issue 1 2010M. Kilic Summary Penile color Doppler sonography is a valuable method for evaluating erectile dysfunction. However, there are some concerns about the safety of this method due to the intracorporeal pharmacological injection, which may cause priapism as a complication, resulting in penile fibrosis. To evaluate the actual incidence of papaverine-induced priapism in patients with erectile dysfunction (ED) who underwent penile colour Doppler sonography and to determine the safety of this diagnostic tool, a retrospective study was conducted using the database of our institution. A total of 672 men with ED underwent penile color Doppler ultrasonography with the intracorporeal injection of 60 mg papaverine hydrochloride. The patient characteristics of priapism cases were retrospectively evaluated. Priapism in 18 of the 672 patients (2.68%) was successfully treated with blood aspiration, irrigation and injection of an ,-agonist medication, when needed. Patients with priapism were younger compared with those without priapism; mean age 45 ± 12.51 (20,68) versus 50.93 ± 12.04 (17,78) (P < 0.001). Penile Doppler ultrasound is a safe procedure in evaluating erectile dysfunction. The incidence of priapism, which is the most important complication of this procedure, is low and can be managed successfully with conservative approaches. [source] A prospective study of diagnosis of Toxoplasma gondii infection after bone marrow transplantation,APMIS, Issue 5 2008BENJAMIN EDVINSSON Active infection with Toxoplasma gondii in immunocompromised transplant recipients can lead to toxoplasmosis, which may have a rapid disease course and in some cases be fatal. It is of paramount importance to diagnose toxoplasmosis at an early stage, and to initiate specific treatment to improve the outcome. Polymerase chain reaction (PCR) is today the primary diagnostic tool to diagnose toxoplasmosis in immunocompromised patients. Timely diagnosis may, however, be difficult if toxoplasmosis is at first asymptomatic. To investigate the magnitude of toxoplasmosis after bone marrow transplantation (BMT), we conducted a screening study by PCR where 21 autologous and 12 allogeneic BMT recipients were included. Peripheral blood samples were taken one week prior to BMT; thereafter, blood samples were drawn weekly for the first 6 months, and monthly up to one year after BMT. The samples were analyzed by conventional PCR and real-time PCR. T. gondii DNA was detected in peripheral blood from one patient 5 days post allogeneic BMT. There were no clinical signs of toxoplasmosis. Medical records were reviewed and showed a previously undiagnosed eye infection in another allogeneic BMT recipient. These two patients were seropositive for T. gondii. We concluded that monitoring for T. gondii DNA in peripheral blood samples using PCR might be a valuable method for identifying toxoplasma-seropositive stem cell transplant recipients. [source] Near-infrared lymphatic imaging demonstrates the dynamics of lymph flow and lymphangiogenesis during the acute versus chronic phases of arthritis in miceARTHRITIS & RHEUMATISM, Issue 7 2010Quan Zhou Objective To develop an in vivo imaging method to assess lymphatic draining function in the K/BxN mouse model of inflammatory arthritis. Methods Indocyanine green, a near-infrared fluorescent dye, was injected intradermally into the footpads of wild-type mice, mouse limbs were illuminated with an 806-nm near-infrared laser, and the movement of indocyanine green from the injection site to the draining popliteal lymph node (LN) was recorded with a CCD camera. Indocyanine green near-infrared images were analyzed to obtain 5 measures of lymphatic function across time. Images of K/BxN arthritic mice and control nonarthritic littermates were obtained at 1 month of age, when acute joint inflammation commenced, and again at 3 months of age, when joint inflammation became chronic. Lymphangiogenesis in popliteal LNs was assessed by immunochemistry. Results Indocyanine green and its transport within lymphatic vessels were readily visualized, and quantitative measures were derived. During the acute phase of arthritis, the lymphatic vessels were dilated, with increased indocyanine green signal intensity and lymphatic pulses, and popliteal LNs became fluorescent quickly. During the chronic phase, new lymphatic vessels were present near the foot. However, the appearance of indocyanine green in lymphatic vessels was delayed. The size and area of popliteal LN lymphatic sinuses progressively increased in the K/BxN mice. Conclusion Our findings indicate that indocyanine green near-infrared lymphatic imaging is a valuable method for assessing the lymphatic draining function in mice with inflammatory arthritis. Indocyanine green,near-infrared imaging of K/BxN mice identified 2 distinct lymphatic phenotypes during the acute and chronic phase of inflammation. This technique can be used to assess new therapies for lymphatic disorders. [source] The Alkaline Comet Assay: Towards Validation in Biomonitoring of DNA Damaging ExposuresBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 4 2006Peter Møller The single cell gel electrophoresis (comet) assay is a technically simple and fast method that detects genotoxicity in virtually any mammalian cell type without requirement for cell culture. This review discusses the strength of the comet assay in biomonitoring at its present state of validation. The simple version of the alkaline comet assay detects DNA migration caused by strand breaks, alkaline labile sites, and transient repair sites. By incubation with bacterial glycosylase/endonuclease enzymes, broad classes of oxidative DNA damage, alkylations, and ultraviolet light-induced photoproducts are detected as additional DNA migration. The most widely measured enzyme sensitive sites have been those detected by formamidopyrimidine DNA glycosylase (FPG) and endonuclease III (ENDOIII). Reports from biomonitoring studies show that the basal level of DNA damage in leukocytes is influenced be a variety of lifestyle and environmental exposures, including exercise, air pollution, sunlight, and diet. Although not all types of carcinogenic exposures should be expected to damage DNA in leukocytes, the comet assay is a valuable method for detection of genotoxic exposure in humans. However, the predictive value of the comet assay is unknown because it has not been investigated in prospective cohort studies. Also, it is important that the performance of the assay is investigated in multi-laboratory validation trials. As a tool in risk assessment the comet assay can be used in characterization of hazards. [source] Off-Target Decoding of a Multitarget Kinase Inhibitor by Chemical ProteomicsCHEMBIOCHEM, Issue 7 2009Enrico Missner Abstract Unbiased: Chemical proteomics was used to profile compound interactions in an unbiased fashion. We present here the application of different compound-immobilization routes for decoding nonprotein kinase off-targets of the multitarget kinase inhibitor C1, which interacts with distinct compound moieties. Since the approval of the first selective tyrosine kinase inhibitor, imatinib, various drugs have been developed to target protein kinases. However, due to a high degree of structural conservation of the ATP binding site, off-target effects have been reported for several drugs. Here, we report on off-target decoding for a multitarget protein kinase inhibitor by chemical proteomics, by focusing on interactions with nonprotein kinases. We tested two different routes for the immobilization of the inhibitor on a carrier matrix, and thus identified off-targets that interact with distinct compound moieties. Besides several of the kinases known to bind to the compound, the pyridoxal kinase (PDXK), which has been described to interact with the CDK inhibitor (R)-roscovitine, was captured. The PDXK,inhibitor interaction was shown to occur at the substrate binding site rather than at the ATP binding site. In addition, carbonic anhydrase 2 (CA2) binding was demonstrated, and the determination of the IC50 revealed an enzyme inhibition in the submicromolar range. The data demonstrate that different compound immobilization routes for chemical proteomics approaches are a valuable method to improve the knowledge about the off-target profile of a compound. [source] | ||||||||||||||||