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Biological Conditions (biological + condition)
Selected AbstractsTMAOase Activity of European Hake (Merluccius merluccius) Organs: Influence of Biological Condition and SeasonJOURNAL OF FOOD SCIENCE, Issue 9 2002M. Rey-Mansilla ABSTRACT: Trimethylamine N-oxide demethylase (TMAOase) activity of several internal organs of hake were studied for 2 consecutive y. The correlation between enzymatic activity and season of year, sex, weight, and length were analyzed. While kidney and spleen showed the highest activities, liver, heart, bile, and gall bladder activities were much lower, and in some cases they were below the detection limit. A correlation between TMAOase activity of kidney and season was found. During winter and spring (February to May), the months matching the spawning peak, high activities were detected, while in summer months the activity level was lower. TMAOase activity in the rest of the organs did not seem to have a seasonal influence. Keywords: TMAOase, season, biological condition, hake, soluble protein [source] Biological condition of adult migrants and nonmigrants in Wroc,aw, PolandAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2008Alicja Szklarska Human migration and its economic, social, and demographic effects can lead to health consequences for individuals and populations. In the present study, we estimated differences in health status between migrant (those who had come to Wroc,aw at the age of ,16 years) and nonmigrant (those who had lived in Wroc,aw since birth or had come with their parents) inhabitants of Wroc,aw, Poland. Three hundred and sixty seven males and 496 females aged 40 and 50 underwent medical examination, and were asked to fill out a questionnaire comprising social, demographic, and life style information. Health status was assessed by blood pressure, heart rate, fasting lipid profile, glucose, height, and measures of fatness (BMI, WHR, sum of skinfolds). Comparisons were made based on Borkan's and Norris's profiles. Student's t -test showed significant differences in diastolic blood pressure, heart rate, total cholesterol, and glucose levels between two groups of males, in favor of migrants. Male migrants were also significantly taller than their peers born in Wroc,aw. In females, migrants had significantly lower blood pressure and heart rate than nonmigrants. In interpreting the results two possible, not mutually exclusive, mechanisms are proposed: selective spatial mobility, and changes toward healthier life style as an adaptation to new urban environment. Am. J. Hum. Biol., 2008. © 2007 Wiley-Liss, Inc. [source] Assigning macroinvertebrate tolerance classifications using generalised additive modelsFRESHWATER BIOLOGY, Issue 5 2004Lester L. Yuan Summary 1. Macroinvertebrates are frequently classified in terms of their tolerance to human disturbance and pollution. These tolerance values have been used effectively to assess the biological condition of running waters. 2. Generalised additive models were used to associate the presence and absence of different macroinvertebrate genera with different environmental gradients. The model results were then used to classify each genera as sensitive, intermediately tolerant or tolerant to different stressor gradients as quantified by total phosphorus concentration, sulphate ion concentration, qualitative habitat score and stream pH. The analytical approach provided a means of estimating stressor-specific tolerance classifications while controlling for covarying, natural environmental gradients. 3. Computed tolerance classification generally conformed with expectations and provided some capacity for distinguishing between different stressors in test data. [source] Evaluation of effluent toxicity as an indicator of aquatic life condition in effluent-dominated streams: A pilot studyINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 4 2008Jerry Diamond Abstract The types and quality of data needed to determine relationships between chronic whole effluent toxicity (WET) test results and in-stream biological condition were evaluated using information collected over a 1.5-y period from 6 different sites across the United States. A data-quality-objectives approach was used that included several proposed measurement quality objectives (MQOs) that specified desired precision, bias, and sensitivity of methods used. The 6 facilities used in this study (4 eastern and 2 western United States) all had design effluent concentrations >60% of the stream flow. In addition to at least quarterly chronic Ceriodaphnia dubia, Pimephales promelas (fathead minnow), and Selenastrum capricornutum (green algae) WET tests, other tests were conducted to address MQOs, including splits, duplicates, and blind positive and negative controls. Macroinvertebrate, fish, and periphyton bioassessments were conducted at multiple locations upstream and downstream of each facility. The test acceptance criteria of the US Environmental Protection Agency (USEPA) were met for most WET tests; however, this study demonstrated the need to incorporate other MQOs (minimum and maximum percent significant difference and performance on blind samples) to ensure accurate interpretation of effluent toxicity. More false positives, higher toxicity, and more "failed" (noncompliant) tests were observed using no-observed-effect concentration (NOEC) as compared to the IC25 endpoint (concentration causing ,25% decrease in organism response compared to controls). Algae tests often indicated the most effluent toxicity in this study; however, this test was most susceptible to false positives and high interlaboratory variability. Overall, WET test results exhibited few relationships with bioassessment results even when accounting for actual effluent dilution. In general, neither frequency of WET noncompliance nor magnitude of toxicity in tests were significantly related to differences in biological condition upstream and downstream of a discharge. Periphyton assessments were most able to discriminate small changes downstream of the effluent, followed by macroinvertebrates and fish. Although sampling methods were robust, more replicate samples collected upstream and downstream of each facility were needed to increase detection power. In general, macroinvertebrate and periphyton assessments together appeared to be sufficient to address project objectives. [source] TMAOase Activity of European Hake (Merluccius merluccius) Organs: Influence of Biological Condition and SeasonJOURNAL OF FOOD SCIENCE, Issue 9 2002M. Rey-Mansilla ABSTRACT: Trimethylamine N-oxide demethylase (TMAOase) activity of several internal organs of hake were studied for 2 consecutive y. The correlation between enzymatic activity and season of year, sex, weight, and length were analyzed. While kidney and spleen showed the highest activities, liver, heart, bile, and gall bladder activities were much lower, and in some cases they were below the detection limit. A correlation between TMAOase activity of kidney and season was found. During winter and spring (February to May), the months matching the spawning peak, high activities were detected, while in summer months the activity level was lower. TMAOase activity in the rest of the organs did not seem to have a seasonal influence. Keywords: TMAOase, season, biological condition, hake, soluble protein [source] Assessment Tools for Urban Catchments: Developing Stressor Gradients,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2009David W. Bressler Abstract:, This is the first in a series of three articles designed to establish empirically defined biological indicators and thresholds for impairment for urbanized catchments, and to describe a process by which the biological condition of waterbodies in urbanized catchments can be applied. This article describes alternative gradients of urbanization for assessing and selecting a nationally applicable biological index (article 2 ,Purcell et al., this issue) and defining the potential of biological communities within a gradient of cumulative stressors (article 3 ,Paul et al. this issue). Gradients were designed to represent the most prominent mosaic of stressors found in urban settings. A primary urban gradient was assembled based on readily obtained information of urbanization to include three broad-scale parameters: percent urban land use/land cover, population density, and road density. This gradient was used as the standard by which alternative urban gradients, which included fine-scale instream chemical and hydrologic parameters, were assessed. Five alternative gradients were developed to provide numerous environmental management options based on availability of data from water program resources. The urban gradients were developed with the intent that they be applied throughout the country; therefore, data from three different regions of the United States (Mid-Atlantic, Midwest, and Pacific Coast) were used to validate the urban gradient model. Our study showed that a relatively straightforward stressor gradient consisting of human population density, road density, and urban land use is useful in providing a framework for developing relevant biological indicators and evaluating the potential of biological communities as a basis for assessing attainment of designated aquatic life use. [source] Concentrations and partitioning of polychlorinated biphenyls in the surface waters of the southern Baltic Sea,seasonal effectsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2006Kilian E.C. Smith Abstract In the marine environment, the partitioning of hydrophobic organic contaminants, such as polychlorinated biphenyls (PCBs), between the dissolved and suspended matter phases in the water column plays a fundamental role in determining contaminant fate (e.g., air,water exchange or food-chain uptake). Despite the pronounced seasonality in physical, chemical, and biological conditions in temperate marine ecosystems, little is known about the seasonality in organic contaminant partitioning behavior. Surface water from the western Baltic Sea was sampled regularly during an 18-month period between February 2003 and July 2004. The concentrations of seven PCB congeners were determined in the dissolved and particulate organic carbon (POC) phases. An inverse relationship was found between KPOC (i.e., the ratio between the POC-normalized PCB concentration [pg/kg POC] and the dissolved concentration [pg/L]) and temperature. The decrease in the water temperature of 20°C between summer and winter resulted in an increase in KPOC by a factor of approximately five. The POC-normalized PCB concentrations were higher in winter than in summer by a factor of 9 to 20. This reflected the higher KPOC and somewhat greater PCB concentrations in the dissolved phase, and it could have consequences for bioaccumulation of these chemicals in aquatic food webs. The results demonstrate a clear seasonality in contaminant partitioning in the temperate marine environment that should be accounted for when interpreting field data or modeling contaminant fate. [source] Phytoplankton communities and antecedent conditions: high resolution sampling in Esthwaite WaterFRESHWATER BIOLOGY, Issue 10 2006G. MADGWICK Summary 1. The succession of a phytoplankton community was investigated through an intensive period of sampling and related to physical, chemical and biological conditions sampled at an equal, or higher, temporal resolution. 2. Phytoplankton samples were taken on a weekly basis from June to September 2004 and analysed for diversity, species composition, and contribution of different functional groups to total biomass. Physical and chemical data were collected on the sampling days, and physical environmental factors were also logged continuously throughout the period by automatic measuring stations. This continuous logging allowed community structure to be compared with physical data averaged over periods from a day to a week before each sampling date. 3. The Schmidt stability of the lake, a measure of the strength of stratification calculated from thermal data, showed a negative correlation with phytoplankton species diversity. This is consistent with the hypothesis that mixing was preventing exclusion by species that would otherwise dominate in stratified conditions. 4. At a functional level, stress tolerant (S-type) species dominated during the stratified summer conditions, with small, colonising species (C types) and ruderal, disturbance tolerant species (R types) contributing little to the overall biomass. Of the stress tolerant species, the faster growing (SC) phytoplankters were significantly favoured by more stable, stratified conditions and higher solar radiation. Increased abundance of this group resulted in decreased species diversity. Correlations were generally strongest when using the 6- to 7-day averaged physical data, stressing the importance of continuous measurements of these drivers in phytoplankton studies. [source] Melatonin generates singlet oxygen on laser irradiation but acts as a quencher when irradiated by lamp photolysisJOURNAL OF PINEAL RESEARCH, Issue 3 2005D. S. Maharaj Abstract:, Melatonin, a naturally occurring chemical mediator, although assigned a diverse range of functions, has attracted interest in recent years because of its ability to function as a free radical scavenger. Because of the implications of singlet oxygen in neurotoxicity, the objective of the study was to investigate the ability of melatonin to quench singlet oxygen generated using laser irradiation or lamp photolysis. The results show that melatonin produces radicals upon laser irradation while the lamp photolysis studies show that melatonin is able to scavenge singlet oxygen produced by naphthalene. While melatonin is a free radical scavenger under biological conditions, it acts as a generator of singlet oxygen and or radicals (as ,, is 1.41) when irradiated with laser light, implying that it has the potential to be used in photodynamic therapy in the destruction of tumors. [source] Use of peptide for selective and sensitive detection of an Anthrax biomarker via peptide recognition and surface-enhanced Raman scatteringJOURNAL OF RAMAN SPECTROSCOPY, Issue 2 2010Kyungtag Ryu Abstract A short 16-amino acid peptide has been used in place of an antibody to selectively detect the specific Anthrax biomarker, protective antigen (PA), using surface-enhanced Raman scattering (SERS). Peptides are more stable than antibodies under various biological conditions and are easily synthesized for a specific target. A peptide that has high affinity to PA was conjugated onto gold nanoparticles along with a Raman reporter and then incubated in various concentrations of PA. Parallel studies in which the peptide sequence was replaced with an antibody were performed to compare the performance of the two methodologies. Both the peptide and antibody functionalized nanoparticles were able to specifically detect PA concentrations down to 6.1 fM. These results demonstrate that these short, robust peptides can be used in the place of traditional antibodies to specifically recognize target biomarkers in the field for the potential diagnosis of disease. Copyright © 2010 John Wiley & Sons, Ltd. [source] NATURAL RESTABILIZATION OF STREAM CHANNELS IN URBAN WATERSHEDS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2000Patricia C. Henshaw ABSTRACT: Stream channels are known to change their form as a result of watershed urbanization, but do they restabilize under subsequent conditions of constant urban land use? Streams in seven developed and developing watersheds (drainage areas 5,35 km2) in the Puget Sound lowlands were evaluated for their channel stability and degree of urbanization, using field and historical data. Protocols for determining channel stability by visual assessment, calculated bed mobility at bankfull flows, and resurveyed cross-sections were compared and yielded nearly identical results. We found that channel restabilization generally does occur within one or two decades of constant watershed land use, but it is not universal. When (or if) an individual stream will restabilize depends on specific hydrologic and geomorphic characteristics of the channel and its watershed; observed stability is not well predicted by simply the magnitude of urban development or the rate of ongoing land-use change. The tendency for channel restabilization suggests that management efforts focused primarily on maintaining stability, particularly in a still-urbanizing watershed, may not always be necessary. Yet physical stability alone is not a sufficient condition for a biologically healthy stream, and additional rehabilitation measures will almost certainly be required to restore biological conditions in urban systems. [source] Impact of low-frequency hotspot mutation R282Q on the structure of p53 DNA-binding domain as revealed by crystallography at 1.54,Å resolutionACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2008Chao Tu Tumor suppressor p53 is a sequence-specific DNA-binding protein and its central DNA-binding domain (DBD) harbors six hotspots (Arg175, Gly245, Arg248, Arg249, Arg273 and Arg282) for human cancers. Here, the crystal structure of a low-frequency hotspot mutant, p53DBD(R282Q), is reported at 1.54,Å resolution together with the results of molecular-dynamics simulations on the basis of the structure. In addition to eliminating a salt bridge, the R282Q mutation has a significant impact on the properties of two DNA-binding loops (L1 and L3). The L1 loop is flexible in the wild type, but it is not flexible in the mutant. The L3 loop of the wild type is not flexible, whereas it assumes two conformations in the mutant. Molecular-dynamics simulations indicated that both conformations of the L3 loop are accessible under biological conditions. It is predicted that the elimination of the salt bridge and the inversion of the flexibility of L1 and L3 are directly or indirectly responsible for deactivating the tumor suppressor p53. [source] On Gene Ranking Using Replicated Microarray Time Course DataBIOMETRICS, Issue 1 2009Yu Chuan Tai Summary Consider the ranking of genes using data from replicated microarray time course experiments, where there are multiple biological conditions, and the genes of interest are those whose temporal profiles differ across conditions. We derive a multisample multivariate empirical Bayes' statistic for ranking genes in the order of differential expression, from both longitudinal and cross-sectional replicated developmental microarray time course data. Our longitudinal multisample model assumes that time course replicates are independent and identically distributed multivariate normal vectors. On the other hand, we construct a cross-sectional model using a normal regression framework with any appropriate basis for the design matrices. In both cases, we use natural conjugate priors in our empirical Bayes' setting which guarantee closed form solutions for the posterior odds. The simulations and two case studies using published worm and mouse microarray time course datasets indicate that the proposed approaches perform satisfactorily. [source] Identification of mouse heart transcriptomic network sensitive to various heart diseasesBIOTECHNOLOGY JOURNAL, Issue 5 2008Seong-Eui Hong Abstract Exploring biological systems from highly complex datasets is an important task for systems biology. The present study examined co-expression dynamics of mouse heart transcriptome by spectral graph clustering (SGC) to identify a heart transcriptomic network. SGC of microarray data produced 17 classified biological conditions (called condition spectrum, CS) and co-expression patterns by generating bi-clusters. The results showed dynamic co-expression patterns with a modular structure enriched in heart-related CS (CS-1 and -13) containing abundant heart-related microarray data. Consequently, a mouse heart transcriptomic network was constructed by clique analysis from the gene clusters exclusively present in the heart-related CS; 31 cliques were used for constructing the network. The participating genes in the network were closely associated with important cardiac functions (e. g., development, lipid and glycogen metabolisms). Online Mendelian Inheritance in Man (OMIM) database indicates that mutations of the genes in the network induced serious heart diseases. Many of the tested genes in the network showed significantly altered gene expression in an animal model of hypertrophy. The results suggest that the present approach is critical for constructing a heart-related transcriptomic network and for deducing important genes involved in the pathogenesis of various heart diseases. [source] Vinyl-Pyridinium Triphenylamines: Novel Far-Red Emitters with High Photostability and Two-Photon Absorption Properties for Staining DNACHEMBIOCHEM, Issue 4 2007Clémence Allain Dr. Abstract A series of mono-, bis- and trisvinyl-pyridinium triphenylamines (TP-py) has been synthesised and evaluated for its one- and two-photon absorption (2PA) induced-fluorescence properties under biological conditions. Interestingly, these compounds are only weakly fluorescent in water, whereas their fluorescence emissions are strongly restored (exaltation factors of 20,100) upon binding to double-stranded DNA. Additional measurements in glycerol indicate that the fluorescence increases are the result of immobilisation of the dyes in the DNA matrix, which inhibits rotational de-excitation modes. This particular feature is especially remarkable in the case of the bis and tris derivatives (TP-2,py, TP-3,py), which each display a high affinity (Kd ,,M) for dsDNA. TPIF measurements have shown that TP-2,py and TP-3,py each have a large 2PA cross section (, up to 700 GM) both in glycerol and in the presence of DNA, which ranks them amongst the best 2PA biological fluorophores. Finally, one- and two-photon confocal imaging in cells revealed that these compounds perform red staining (,em=660,680 nm) of nuclear DNA with excellent contrast. The remarkable optical properties of the TP-py series, combined with their high photostability and their easy synthetic access, make these compounds extremely attractive for use in confocal and 2PA microscopy. [source] Severe Mental Illness Needs Empirically Supported Assessment and TreatmentsCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 4 2006Leslie Sim This commentary describes the prevailing mental health-care paradigm as hindering the advantageous and sensible utilization of psychologists in the treatment of individuals with severe mental illness (SMI). The commentary suggests that the failure to utilize clinical psychology in treating SMI is part of a longstanding trend toward the narrow viewing of SMI as exclusively biological conditions requiring medical treatment exclusively. In neglecting a host of treatment interventions, a broad knowledge base of empirically supported treatments, and specific assessment skills available to clinical psychologists, an opportunity is missed to better enhance the lives of the individuals with SMI and even facilitate the effectiveness of biological interventions. This commentary raises the troubling implications of the underutilization of psychologists in the care of those with SMI, including the moral imperative raised by our absence, the neglect of the development and implementation of effective psychological interventions, and the erroneous message this absence sends about what it is that psychologists practice and who they are able to help. This commentary describes some of the ways in which clinical psychologists have contributed to the care of SMI and argues that the expertise of clinical psychologists in empirically supported assessment and treatment is a resource that should not be deprived to members of society desperately in need of treatments if we are to continue to reduce suffering and enhance quality of life. This commentary elucidates some ways in which members of the profession of clinical psychology can meet their ethical obligation to take part in the treatment of SMI. [source] Priming the productivity pump: flood pulse driven trends in suspended algal biomass distribution across a restored floodplainFRESHWATER BIOLOGY, Issue 8 2006DYLAN S. AHEARN Summary 1. Chlorophyll a (Chl a) distribution across a 0.36 km2 restored floodplain (Cosumnes River, California) was analysed throughout the winter and spring flood season from January to June 2005. In addition, high temporal-resolution Chl a measurements were made in situ with field fluorometers in the floodplain and adjacent channel. 2. The primary objectives were to characterise suspended algal biomass distribution across the floodplain at various degrees of connection with the channel and to correlate Chl a concentration and distribution with physical and chemical gradients across the floodplain. 3. Our analysis indicates that periodic connection and disconnection of the floodplain with the channel is vital to the functioning of the floodplain as a source of concentrated suspended algal biomass for downstream aquatic ecosystems. 4. Peak Chl a levels on the floodplain occurred during disconnection, reaching levels as high as 25 ,g L,1. Chl a distribution across the floodplain was controlled by residence time and local physical/biological conditions, the latter of which were primarily a function of water depth. 5. During connection, the primary pond on the floodplain exhibited low Chl a (mean = 3.4 ,g L,1) and the shallow littoral zones had elevated concentrations (mean = 4.6 ,g L,1); during disconnection, shallow zone Chl a increased (mean = 12.4 ,g L,1), but the pond experienced the greatest algal growth (mean = 14.7 ,g L,1). 6. Storm-induced floodwaters entering the floodplain not only displaced antecedent floodplain waters, but also redistributed floodplain resources, creating complex mixing dynamics between parcels of water with distinct chemistries. Incomplete replacement of antecedent floodplain waters led to localised hypoxia in non-flushed areas. 7. The degree of complexity revealed in this analysis makes clear the need for high-resolution spatial and temporal studies such as this to begin to understand the functioning of dynamic and heterogeneous floodplain ecosystems. [source] | ||||||||||||||||