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2.
Sci Total Environ ; 904: 166798, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37673263

RESUMO

An integrated biological effects study using field transplanted mussels was applied to determine the potential biological effects of an effluent discharge from an aluminium smelter into a Norwegian fjord. Chemical body burden and biological effects were measured in mussels positioned downstream (1, 2, 5, 10 and 20 km) from the aluminium smelters discharge for a period of 6 weeks. A suite of biomarkers, from whole organism to subcellular responses were measured. Chemical concentrations in mussel tissues were low; however, a change in the PAC (polyaromatic compound) profile from high to low pyrogenic influence provided evidence of exposure to the smelter's effluent. Overall, the biological responses observed where greater in the mussels positioned closest to the smelter (1-5 km). Lowest chemical accumulation and biomarker responses were observed in mussels positioned 10 km from the smelter and were considered as the reference field population. Mussels located furthest from the smelter (20 km) exhibited significant biomarker responses and suggested a different contaminant source within the fjord. The integrated biological response index (IBR) was applied and reflected the expected level of exposure to the smelters discharge, with highest IBR calculated in mussels positioned closest to the discharge (1-5 km). Principal component analysis (PCA) also differentiated among mussel groups, with the most impacted located closest to the smelter. Not one chemical factor could explain the biological responses observed in mussels, but the presence of PAH16, PAH41 and metals Mn, Ni and Cr were the main contributors measured to the higher stress seen in the mussels from the 1 and 5 km groups.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Água/análise , Alumínio/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Bivalves/química , Biomarcadores/análise
3.
Sci Total Environ ; 655: 1409-1419, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30577132

RESUMO

Veterinary medicinal products (VMPs) are widely used within the fish farming industry to control sea lice infestations. There is concern that wild and farmed mussels in the vicinity to these fish farms may be exposed and subsequently bioaccumulate these chemicals, which could pose a threat to human health. To understand the fate of these chemicals in the environment, controlled laboratory exposures were performed to establish the uptake and depuration of selected VMPs in the blue mussel (Mytilus edulis). The VMPs included teflubenzuron, emamectin benzoate and deltamethrin. The effects of salinity on the bioaccumulation of teflubenzuron were also investigated to see whether mussels in brackish waters exhibit different bioaccumulation dynamics. Salinity had no significant effect on the uptake or depuration curves for teflubenzuron down to 15‰. The uptake rate constants (k1) for teflubenzuron, emamectin benzoate and deltamethrin in mussels were 192, 4.82 and 2003, with kinetic bioconcentration factors (BCFs) of 1304, 49 and 2516. Depuration rate constants (k2) were also found to differ between the three VMPs at 0.147, 0.048 and 0.796 for teflubenzuron, emamectin benzoate and deltamethrin, with calculated elimination half-lives (t1/2)of 4.7, 14 and 0.87 days. The longer elimination half-lives for teflubenzuron and emamectin benzoate, suggest that these chemicals accumulate in blue mussels and therefore have the potential to bioaccumulate in wild and farmed mussel populations in the environment.


Assuntos
Benzamidas/metabolismo , Ivermectina/análogos & derivados , Mytilus edulis/metabolismo , Nitrilas/metabolismo , Piretrinas/metabolismo , Drogas Veterinárias/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Ivermectina/metabolismo , Cinética
4.
Sci Total Environ ; 644: 1056-1069, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30743819

RESUMO

The blue mussel (Mytilus sp.) has been used to assess the potential biological effects of the discharge effluent from the Omya Hustadmarmor mine, which releases its tailings into the Frænfjord near Molde, Norway. Chemical body burden and a suite of biological effects markers were measured in mussels positioned for 8 weeks at known distances from the discharge outlet. The biomarkers used included: condition index (CI); stress on stress (SoS); micronuclei formation (MN); acetylcholine esterase (AChE) inhibition, lipid peroxidation (LPO) and Neutral lipid (NL) accumulation. Methyl triethanol ammonium (MTA), a chemical marker for the esterquat based flotation chemical (FLOT2015), known to be used at the mine, was detected in mussels positioned 1500 m and 2000 m downstream from the discharge outlet. Overall the biological responses indicated an increased level of stress in mussels located closest to the discharge outlet. The same biomarkers (MN, SoS, NL) were responsible for the integrated biological response (IBR/n) of the two closest stations and indicates a response to a common point source. The integrated biological response index (IBR/n) reflected the expected level of exposure to the mine effluent, with the highest IBR/n calculated in mussels positioned closest to the discharge. Principal component analysis (PCA) also showed a clear separation between the mussel groups, with the most stressed mussels located closest to the mine tailing outlet. Although not one chemical factor could explain the increased stress on the mussels, highest metal (As, Co, Ni, Cd, Zn, Ag, Cu, Fe) and MTA concentrations were detected in the mussel group located closest to the mine discharge.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Mineração , Mytilus/fisiologia , Poluentes Químicos da Água/metabolismo , Animais , Noruega , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Neuroimage Clin ; 12: 478-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27625988

RESUMO

BACKGROUND: Protracted methamphetamine (MA) use is associated with decreased control over drug craving and altered brain volume in the frontostriatal network. However, the nature of volumetric changes following a course of psychological intervention for MA use is not yet known. METHODS: 66 males (41 MA patients, 25 healthy controls, HC) between the ages of 18-50 were recruited, the MA patients from new admissions to an in-patient drug rehabilitation centre and the HC via public advertisement, both in Cape Town, South Africa. 17 MA patients received 4 weeks of treatment as usual (TAU), and 24 MA patients completed TAU plus daily 30-minute cognitive training (CT) using an N-back working memory task. Magnetic resonance imaging (MRI) at baseline and 4-week follow-up was acquired and voxel-based morphometry (VBM) was used for analysis. RESULTS: TAU was associated with larger bilateral striatum (caudate/putamen) volume, whereas CT was associated with more widespread increases of the bilateral basal ganglia (incorporating the amygdala and hippocampus) and reduced bilateral cerebellum volume coinciding with improvements in impulsivity scores. CONCLUSIONS: While psychological intervention is associated with larger volume in mesolimbic reward regions, the utilisation of additional working memory training as an adjunct to treatment may further normalize frontostriatal structure and function.


Assuntos
Gânglios da Base/patologia , Memória de Curto Prazo/fisiologia , Metanfetamina/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/patologia , Transtornos Relacionados ao Uso de Substâncias/terapia , Adolescente , Adulto , Gânglios da Base/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Humanos , Comportamento Impulsivo , Pacientes Internados , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Resultado do Tratamento , Adulto Jovem
6.
Mar Pollut Bull ; 91(1): 82-6, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25558019

RESUMO

A bioassay method using the early life stages (germlings) of macroalgae was developed to detect toxicity of anti-fouling paint biocides. A laboratory based bioassay using Ulva intestinalis and Fucus spiralis germlings was performed with 4 common anti-fouling biocides (tributyltin (TBT), Irgarol 1051, Diuron and zinc sulphate), over a range of environmentally relevant concentrations (0.0033-10 µg l(-1)). Comparison between the two species showed that germlings of U. intestinalis were better adapted for in-situ monitoring, as germlings of F. spiralis appeared to be too robust to display sufficient growth differences. The response of U. intestinalis germling growth appeared to reflect environmental biocide concentrations. Overall the developed method showed potential for the assessment of the sub-lethal effects of anti-fouling biocides on the early developmental stages of U. intestinalis.


Assuntos
Desinfetantes/análise , Monitoramento Ambiental/métodos , Alga Marinha/efeitos dos fármacos , Poluentes Químicos da Água/análise , Análise de Variância , Bioensaio , Cloretos/toxicidade , Desinfetantes/toxicidade , Diurona/toxicidade , Relação Dose-Resposta a Droga , Fucus/efeitos dos fármacos , Fucus/crescimento & desenvolvimento , Alga Marinha/crescimento & desenvolvimento , Especificidade da Espécie , Compostos de Trialquitina/toxicidade , Triazinas/toxicidade , Ulva/efeitos dos fármacos , Ulva/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Compostos de Zinco/toxicidade
7.
Acta Psychiatr Scand ; 131(4): 244-55, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25223374

RESUMO

OBJECTIVE: To provide a neurobiological basis of eating disorders for clinicians and to enlighten how comparing neurobiology and eating disorders with neurobiology of other psychiatric illnesses can improve treatment protocols. METHOD: A selective review on the neurobiology of eating disorders. The article focuses on clinical research on humans with consideration of the anatomical, neural, and molecular basis of eating disorders. RESULTS: The neurobiology of people with eating disorders is altered. Many of the neurobiological regions, receptors, and chemical substrates that are affected in other mental illnesses also play an important role in eating disorders. More knowledge about the neurobiological overlap between eating disorders and other psychiatric populations will help when developing treatment protocols not the least regarding that comorbidity is common in patients with EDs. CONCLUSION: Knowledge about the underlying neurobiology of eating disorders will improve treatment intervention and will benefit from comparisons with other mental illnesses and their treatments.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/patologia , Humanos , Neuroimagem/métodos
8.
Neuroimage ; 102 Pt 2: 923-37, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24927986

RESUMO

BACKGROUND: Handgrip is a ubiquitous human movement that was critical in our evolution. However, the differences in brain activity between grip type (i.e. power or precision) and pattern (i.e. dynamic or static) are not fully understood. In order to address this, we performed Activation Likelihood Estimation (ALE) analysis between grip type and grip pattern using functional magnetic resonance imaging (fMRI) data. ALE provides a probabilistic summary of the BOLD response in hundreds of subjects, which is often beyond the scope of a single fMRI experiment. METHODS: We collected data from 28 functional magnetic resonance data sets, which included a total of 398 male and female subjects. Using ALE, we analyzed the BOLD response during power, precision, static and dynamic grip in a range of forces and age in right handed healthy individuals without physical impairment, cardiovascular or neurological dysfunction using a variety of grip tools, feedback and experimental training. RESULTS: Power grip generates unique activation in the postcentral gyrus (areas 1 and 3b) and precision grip generates unique activation in the supplementary motor area (SMA, area 6) and precentral gyrus (area 4a). Dynamic handgrip generates unique activation in the precentral gyrus (area 4p) and SMA (area 6) and of particular interest, both dynamic and static grip share activation in the area 2 of the postcentral gyrus, an area implicated in the evolution of handgrip. According to effect size analysis, precision and dynamic grip generates stronger activity than power and static, respectively. CONCLUSION: Our study demonstrates specific differences between grip type and pattern. However, there was a large degree of overlap in the pre and postcentral gyrus, SMA and areas of the frontal-parietal-cerebellar network, which indicates that other mechanisms are potentially involved in regulating handgrip. Further, our study provides empirically based regions of interest, which can be downloaded here within, that can be used to more effectively study power grip in a range of populations and conditions.


Assuntos
Encéfalo/fisiologia , Força da Mão/fisiologia , Imageamento por Ressonância Magnética , Neuroimagem , Feminino , Lobo Frontal , Humanos , Masculino , Lobo Parietal
9.
Obesity (Silver Spring) ; 21(8): 1548-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23585292

RESUMO

OBJECTIVE: Cognitive factors and anticipation are known to influence food intake. The current study examined the effect of anticipation and actual consumption of food on hormone (ghrelin, cortisol, and insulin) and glucose levels, appetite and ad libitum intake, to assess whether changes in hormone levels might explain the predicted differences in subsequent food intake. DESIGN AND METHODS: During four breakfast sessions, participants consumed a yogurt preload that was either low caloric (LC: 180 kcal/300 g) or high caloric (HC: 530 kcal/300 g) and was provided with either consistent or inconsistent calorie information (i.e., stating the caloric content of the preload was low or high). Appetite ratings and hormone and glucose levels were measured at baseline (t = 0), after providing the calorie information about the preload (t = 20), after consumption of the preload (t = 40), and just before ad libitum intake (t = 60). RESULTS: Ad libitum intake was lower after HC preloads (as compared to LC preloads; P < 0.01). Intake after LC preloads was higher when provided with (consistent) LC information (467±254 kcal) as compared to (inconsistent) HC information (346±210 kcal), but intake after the HC preloads did not depend on the information provided (LC information: 290±178 kcal, HC information: 333±179 kcal; caloric load*information P = 0.03). Hormone levels did not respond in an anticipatory manner, and the post-prandial responses depended on actual calories consumed. CONCLUSIONS: These results suggest that both cognitive and physiological information determine food intake. When actual caloric intake was sufficient to produce physiological satiety, cognitive factors played no role; however, when physiological satiety was limited, cognitively induced satiety reduced intake to comparable levels.


Assuntos
Ingestão de Alimentos/fisiologia , Ingestão de Energia/fisiologia , Apetite/fisiologia , Glicemia/metabolismo , Estudos Cross-Over , Feminino , Grelina/sangue , Humanos , Fome/fisiologia , Hidrocortisona/sangue , Insulina/sangue , Saciação/fisiologia , Paladar , Iogurte , Adulto Jovem
10.
Int J Obes (Lond) ; 37(2): 230-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22290540

RESUMO

OBJECTIVE: Obesity adversely affects frontal lobe brain structure and function. Here we sought to show that people who are obese versus those who are of normal weight over a 5-year period have differential global and regional brain volumes. DESIGN: Using voxel-based morphometry, contrasts were done between those who were recorded as being either obese or of normal weight over two time points in the 5 years prior to the brain scan. In a post-hoc preliminary analysis, we compared scores for obese and normal weight people who completed the trail-making task. SUBJECTS: A total of 292 subjects were examined following exclusions (for example, owing to dementia, stroke and cortical infarcts) from the Prospective Investigation of the Vasculature in Uppsala Seniors cohort with a body mass index of normal weight (<25 kg m(-2)) or obese (30 kg m(-2)). RESULTS: People who were obese had significantly smaller total brain volumes and specifically, significantly reduced total gray matter (GM) volume (GMV) (with no difference in white matter or cerebrospinal fluid). Initial exploratory whole brain uncorrected analysis revealed that people who were obese had significantly smaller GMV in the bilateral supplementary motor area, bilateral dorsolateral prefrontal cortex (DLPFC), left inferior frontal gyrus and left postcentral gyrus. Secondary more stringent corrected analyses revealed a surviving cluster of GMV difference in the left DLPFC. Finally, post-hoc contrasts of scores on the trail-making task, which is linked to DLPFC function, revealed that obese people were significantly slower than those of normal weight. CONCLUSION: These findings suggest that in comparison with normal weight, people who are obese have smaller GMV, particularly in the left DLPFC. Our results may provide evidence for a potential working memory mechanism for the cognitive suppression of appetite that may lower the risk of developing obesity in later life.


Assuntos
Índice de Massa Corporal , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/patologia , Lobo Frontal/patologia , Neuroimagem/métodos , Obesidade/complicações , Idade de Início , Idoso , Mapeamento Encefálico , Análise por Conglomerados , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Obesidade/epidemiologia , Obesidade/patologia , Obesidade/fisiopatologia , Tamanho do Órgão , Estudos Prospectivos , Suécia/epidemiologia
11.
Aquat Toxicol ; 127: 21-35, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22310169

RESUMO

In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the commonly used stress biomarkers, as they provided valuable information on the physiological status of the studied organisms. Interpretation of the seasonality in oxidative stress biomarkers was in general difficult but TOSC and lipid peroxidation were preferred over the antioxidant enzyme activities. This study is the first reporting seasonal baseline in these three species in a sub-Arctic location. Overall, the Icelandic scallop was considered the most adequate organism for environmental monitoring in the Barents Sea due to the interpretability of the biomarker data as well as its abundance, ease to handle and wide distribution from the southern Barents Sea to Svalbard.


Assuntos
Biomarcadores/análise , Monitoramento Ambiental , Gadus morhua/fisiologia , Mytilus edulis/fisiologia , Pectinidae/fisiologia , Estações do Ano , Animais , Gadus morhua/metabolismo , Mytilus edulis/metabolismo , Oceanos e Mares , Pectinidae/metabolismo , Poluentes Químicos da Água/toxicidade
12.
Neuroimage ; 59(3): 2962-73, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22001789

RESUMO

Functional Magnetic Resonance Imaging (fMRI) demonstrates that the subliminal presentation of arousing stimuli can activate subcortical brain regions independently of consciousness-generating top-down cortical modulation loops. Delineating these processes may elucidate mechanisms for arousal, aberration in which may underlie some psychiatric conditions. Here we are the first to review and discuss four Activation Likelihood Estimation (ALE) meta-analyses of fMRI studies using subliminal paradigms. We find a maximum of 9 out of 12 studies using subliminal presentation of faces contributing to activation of the amygdala, and also a significantly high number of studies reporting activation in the bilateral anterior cingulate, bilateral insular cortex, hippocampus and primary visual cortex. Subliminal faces are the strongest modality, whereas lexical stimuli are the weakest. Meta-analyses independent of studies using Regions of Interest (ROI) revealed no biasing effect. Core neuronal arousal in the brain, which may be at first independent of conscious processing, potentially involves a network incorporating primary visual areas, somatosensory, implicit memory and conflict monitoring regions. These data could provide candidate brain regions for the study of psychiatric disorders associated with aberrant automatic emotional processing.


Assuntos
Tonsila do Cerebelo/fisiologia , Nível de Alerta/fisiologia , Córtex Cerebral/fisiologia , Giro do Cíngulo/fisiologia , Hipocampo/fisiologia , Imageamento por Ressonância Magnética , Estimulação Subliminar , Córtex Visual/fisiologia , Estimulação Acústica , Humanos , Processamento de Imagem Assistida por Computador , Estimulação Luminosa
13.
Front Hum Neurosci ; 6: 347, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23335892

RESUMO

BACKGROUND: Social anxiety disorder (SAD) is characterized by abnormal fear and anxiety in social situations. Functional magnetic resonance imaging (fMRI) is a brain imaging technique that can be used to demonstrate neural activation to emotionally salient stimuli. However, no attempt has yet been made to statistically collate fMRI studies of brain activation, using the activation likelihood-estimate (ALE) technique, in response to emotion recognition tasks in individuals with SAD. METHODS: A systematic search of fMRI studies of neural responses to socially emotive cues in SAD was undertaken. ALE meta-analysis, a voxel-based meta-analytic technique, was used to estimate the most significant activations during emotional recognition. RESULTS: Seven studies were eligible for inclusion in the meta-analysis, constituting a total of 91 subjects with SAD, and 93 healthy controls. The most significant areas of activation during emotional vs. neutral stimuli in individuals with SAD compared to controls were: bilateral amygdala, left medial temporal lobe encompassing the entorhinal cortex, left medial aspect of the inferior temporal lobe encompassing perirhinal cortex and parahippocampus, right anterior cingulate, right globus pallidus, and distal tip of right postcentral gyrus. CONCLUSION: The results are consistent with neuroanatomic models of the role of the amygdala in fear conditioning, and the importance of the limbic circuitry in mediating anxiety symptoms.

14.
Appl Microbiol Biotechnol ; 64(4): 486-92, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14647990

RESUMO

Crude cell extracts of Pseudomonas putida F6 transformed 4-substituted fluoro-, chloro-, bromo- and iodo-phenol without the exogenous addition of cofactors. The rate of substrate consumption decreased with increasing substituent size (F>Cl>Br>I). Biotransformations resulted in greater than 95% utilisation of the halogenated substrate. Product accumulation was observed in incubations with 4-chloro, 4-bromo- and 4-iodo-phenol. These products were identified as the corresponding 4-substituted catechols. Transformation of 4-fluorophenol did not result in the accumulation of the corresponding catechol; however, manipulation of the reaction conditions by incorporation of ascorbic acid culminated in the formation of 4-fluorocatechol. Cell extracts of P. putida F6 also showed activity towards a 3-substituted phenol, namely 3-fluorophenol, resulting in the formation of a single product, 4-fluorocatechol.


Assuntos
Catecóis/análise , Fenóis/metabolismo , Pseudomonas putida/metabolismo , Biotransformação , Clorofenóis/metabolismo , Coenzimas , Iodobenzenos/metabolismo , Pseudomonas putida/crescimento & desenvolvimento , Especificidade por Substrato
15.
J Child Adolesc Psychopharmacol ; 11(4): 341-76, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11838819

RESUMO

We surveyed 160 recent studies of adolescent depression (publication dates ranged from March 1996 to August 2000) and identified 33 different diagnostic and symptom measurement instruments being used by various investigators. We also found that more than one in three of the studies measuring depressive symptom severity in adolescents relied on instruments designed for use with adults. We then reviewed in detail the design features and psychometric properties of the 12 instruments most commonly used in studies of adolescent depression and attempted to characterize their strengths and weaknesses. Our main conclusions are as follows: Too many different instruments are being used by investigators, presumably due to a lack of consensus as to which are the most valid and reliable tools. Instruments designed for use in adults and never validated in adolescent populations are frequently used with no evidence for their developmental sensitivity. Many studies are using instruments that demonstrate substantial weaknesses in validity and/or reliability. The need for a parsimonious, easily administered, valid, and reliable tool(s) to diagnose and measure symptom severity in adolescent depression has not yet been met.


Assuntos
Transtorno Depressivo/diagnóstico , Psicologia do Adolescente , Adolescente , Fatores Etários , Humanos , Testes Psicológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
16.
Bioko; Department of Entomology,Natural history Museum Crom well road; 1999. 46 p. figures.
Monografia em Inglês | AIM (África) | ID: biblio-1443209

RESUMO

A literature search has established that the freshwater macro-invertebrate fauna ofBioko is extremely poorly studied and that relatively few species of freshwater insects have been recorded from the island (Appendix 1). Nevertheless, it is apparent from this searc[ and from insects collected on the island during the present study, that the ocp identification manual to aquatic inseas from the Ivory coast @ejoux et al., lggl)and the standard recording form 5620 are adequate for family level recording of specimens collected on the island because all families known from Bioko are covered. There are genera of aquatic insects which are found on Bioko and are not covered, but this is unlikely to seriously distort estimates of community structurq for which they are designed. l'2' The impact of the inseaicide Temephos, used to eradicate Sirrulium dannowms.l. the vector of onchoceriasis, on chironomidae (non-biting midges) genera and odonata (dragonflies) species on three streams on Bioko has been investigated as part of an environmental impaa assessment. 1'3' Adult and larval odonata and larval Chironomidae were surveyed throu-ehout Bioko between 23 Marchand 9 April 1999 to establish the distribution ofthese groups and to indicate whether recolonisation oftreated strezmrs from untreated refugia would be possible to re-establish any non-target ta:ra that were eliminated following rhe Simuliumeradication progriunme.l'4' Treatment of all three trial sfeams with Temephos had an adverse effect on the chironomid fauna with an elimination of up 5u/o of thegenera at sites immediately downstream ofthe treaunent point. Insufficient nurnbers of odonata larvae were present in the samples to draw meaningful conclusions about the direa impact ofthe insecticide on the odonate fauna. However, if the insecticide causes a general reduction in abundance and biodiversity of aquatic macro- invertebrates, the odonate fauna could be expected to decline within a few weeks due to a shortage ofprey l'5 Twenty-five species of Odonata were recorded during the present survey, including six species not previously found in Bioko. The total number of odonata species now known from the island is 48 including one species (Trithemis hartwigt)and one subspecies (Chtorocypha cancellata insulua)that are cunently thought to be endernic. Trithemis hartwigr was not collected during the current survey but has previously only been recorded in the highland region around Moca. Chloruyplw cancellaninsalqwwas collected from several lowland streams during the present survey The dragonfly fauna has two elements, an upland element which includes species that occur above 1000 m only, and a lowland element including several species that do not occur above 500 m. Only three species occurred in both these faunistic elements, but there was a transitional fauna at 600 m that included a few species from each elernent. Much ofthe adult dragonfly fauna is probably seasonal in occurrence and so was not recorded during this brief survey. Certain Libellulidae probably migrate to Bioko from mainland Africa to breed in temporary pools during the wet se.$on. ffis migration us likely to be wind assisted. 1.9. Downstream recolonisation by Odonata of streams treated with inseAicide below 1000 m will not occur since upland strearns do not act as refugia for most ofthe lowland odonate fauna. However, if some permanently flowing lowland sffeams are left untreated these could act as refugia for the lowland fauna. Simultaneous inseaicide fieament of the lowland sections of all rivers on Bioko is likely to result in the elimination of a significant proportion ofthe dragonfly fauna on the island, although recolonisation by some species from the African mainland might be possible over time. The chironomid fauna appeared to be fairly uniform in lowland rivers but samples from the high altitude site included four tu

Assuntos
Oncocercose , Inseticidas , Larva , Saúde Ambiental , Biodiversidade , Invertebrados
17.
J Bacteriol ; 157(2): 460-4, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6363385

RESUMO

The effect of elevated growth temperature on nif mRNA synthesis, nif protein synthesis, and nitrogenase activity was investigated in wild-type and NifL- strains of Klebsiella pneumoniae. Nitrogenase activity is not affected at 41 degrees C; however, nitrogenase is not synthesized at that temperature. Transcription of three nif operons studied is repressed at 41 degrees C. We show that the nifL protein is not required for repression by high temperature and propose that repression of nif at 41 degrees C results from a reversible inactivation of the nifA gene product.


Assuntos
Klebsiella pneumoniae/genética , Fixação de Nitrogênio , Nitrogenase/genética , Acetileno/metabolismo , Repressão Enzimática , Temperatura Alta , Klebsiella pneumoniae/enzimologia , Mutação
18.
J Infect Dis ; 136(5): 633-9, 1977 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-335001

RESUMO

Vaccination with formalin-treated cells of Escherichia coli serotype O6 protected against unilateral retrograde pyelonephritis due to E. coli O6 in rats with partial ureteral obstruction. This protection was manifested not only by less parenchymal destruction and shrinkage of the pyelonephritic left kidney, but also by less secondary pyelonephritis and compensatory hypertrophy in the opposite right kidney. Vaccinated rats eliminated E. coli from the kidney more rapidly, but even when infection persisted in the kidney, the chronic pyelonephritis was less severe in vaccinated rats. High levels of antibody to E. coli lipopolysaccharide were found in vaccinated animals and may have contributed to protection. These results raise the question of whether vaccination ought to be considered for patients predisposed to chronic bacterial pyelonephritis.


Assuntos
Vacinas Bacterianas , Infecções por Escherichia coli/prevenção & controle , Escherichia coli/imunologia , Pielonefrite/prevenção & controle , Animais , Anticorpos Antibacterianos/análise , Peso Corporal , Doença Crônica , Infecções por Escherichia coli/patologia , Rim/patologia , Masculino , Tamanho do Órgão , Prostatite/etiologia , Pielonefrite/patologia , Ratos , Vacinação
19.
Postgrad Med J ; 53(619): 248-50, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-327452

RESUMO

The Microstix system has been tested, in parallel with dipslides, for suitability as a screening technique for the detection of bacteriuria. Results obtained using each method on 228 urine specimens were assessed by comparison with the results of quantitative counts. Dipslides had a higher sensitivity (86-7%) than Microstix. The best specificity (100%) was obtained from those results (77-6%) where both components of the Microstix system were in agreement. Advantages of Microstix are its greater shelf-life and its compactness.


Assuntos
Técnicas Bacteriológicas , Bacteriúria/diagnóstico , Humanos
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