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1.
Int Urogynecol J ; 34(8): 1831-1835, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36752848

RESUMO

INTRODUCTION AND HYPOTHESIS: Health state utility values estimate an individual's valuation of their health-related quality of life. Despite prevalence of recurrent urinary tract infections (rUTIs), the health state utility value of rUTIs is unknown. The primary aim was to determine the utility value of rUTIs using the standard gamble (SG). The secondary aim was to compare the SG utility value with that derived from the EuroQol 5 dimensions (EQ-5D) and visual analog scale (VAS). We hypothesized that a utility value would be successfully derived from the SG and would differ from that derived using the EQ-5D and VAS. METHODS: Nonpregnant, adult English-speaking female patients with a diagnosis of rUTI were recruited and completed the EQ-5D, VAS, and SG (n = 25). Utility values were evaluated using Wilcoxon signed-rank tests and Spearman's rho correlation. RESULTS: Health state utility values varied depending on the assessment tool used: EQ-5D 0.76 (IQR 0.52), VAS 0.70 (IQR 0.30), and SG 0.85 (IQR 0.25). There were differences between VAS and the other two assessment methods (p<0.001), as well as between EQ-5D and SG (p=0.013). Spearman correlation demonstrated a moderately positive correlation between EQ-5D and VAS values (r(25) = 0.59, p=0.0019). CONCLUSIONS: Our data suggest that 0.85 reflects the true health state utility value of rUTIs among nonpregnant adult English-speaking women. The utility value for recurrent UTIs is worse (lower) than that previously published for nonrecurrent UTIs, reflecting the ability of the SG to convey the compounding impact of recurrent disease. In this study, neither the EQ-5D nor the VAS produced results consistent with those found using the SG, which suggests limited validity in this population.


Assuntos
Qualidade de Vida , Infecções Urinárias , Adulto , Humanos , Feminino , Inquéritos e Questionários , Medição da Dor , Escala Visual Analógica , Nível de Saúde
2.
J Exp Biol ; 223(Pt 14)2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32561626

RESUMO

Female-biased mortality has been repeatedly reported in Pacific salmon during their upriver migration in both field studies and laboratory holding experiments, especially in the presence of multiple environmental stressors, including thermal stress. Here, we used coho salmon (Oncorhynchus kisutch) to test whether females exposed to elevated water temperatures (18°C) (i) suppress circulating sex hormones (testosterone, 11-ketotestosterone and estradiol), owing to elevated cortisol levels, (ii) have higher activities of enzymes supporting anaerobic metabolism (e.g. lactate dehydrogenase, LDH), (iii) have lower activities of enzymes driving oxidative metabolism (e.g. citrate synthase, CS) in skeletal and cardiac muscle, and (iv) have more oxidative stress damage and reduced capacity for antioxidant defense [lower catalase (CAT) activity]. We found no evidence that a higher susceptibility to oxidative stress contributes to female-biased mortality at warm temperatures. We did, however, find that females had significantly lower cardiac LDH and that 18°C significantly reduced plasma levels of testosterone and estradiol, especially in females. We also found that relative gonad size was significantly lower in the 18°C treatment regardless of sex, whereas relative liver size was significantly lower in females held at 18°C. Further, relative spleen size was significantly elevated in the 18°C treatments across both sexes, with larger warm-induced increases in females. Our results suggest that males may better tolerate bouts of cardiac hypoxia at high temperature, and that thermal stress may also disrupt testosterone- and estradiol-mediated protein catabolism, and the immune response (larger spleens), in migratory female salmon.


Assuntos
Lactato Desidrogenases , Oncorhynchus kisutch , Salmão , Animais , Estradiol , Feminino , Hormônios Esteroides Gonadais , Masculino , Salmão/fisiologia
3.
Ecology ; 98(3): 608-615, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27984657

RESUMO

Despite many similarities and intuitive links between individual dietary specialization and behavioral inter-individual variation, these phenomena have been studied in isolation, and empirical data confirming relationships between these intraspecific variance sources are lacking. Here we use stable isotope analysis and acoustic telemetry to test the hypothesis that individual specialization in trophic (δ15 N) and littoral/pelagic prey reliance (δ13 C) covary with inter-individual variation in movement in a group of 34 free-swimming burbot (Lota lota). By performing stable isotope analysis on tissues with differing isotopic turnover rates (anal fin and dorsal muscle), in 24 lethally sampled burbot, we demonstrate that individual specialization in trophic niche (δ15 N) and littoral/pelagic prey reliance (δ13 C) occurred within the population. By performing stable isotope analysis on anal fins of a group of telemetry tagged burbot, we were able to show that interactions between trophic niche and littoral/pelagic prey reliance, explained a significant proportion of the subsequent between-individual variance in mean movement rates. These findings demonstrate an empirical connection between behavioral inter-individual variation and dietary specialization, thus providing a substantial expansion of our understanding of the wider ecological consequences of these interesting phenomena.


Assuntos
Dieta/estatística & dados numéricos , Peixes/fisiologia , Animais , Ecologia , Comportamento Alimentar , Água Doce , Isótopos de Nitrogênio , Comportamento Predatório
4.
J Hum Evol ; 112: 148-161, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28760580

RESUMO

Placing the biological adaptations of Pleistocene hominins within a well-resolved ecological framework has been a longstanding goal of paleoanthropology. This effort, however, has been challenging due to the discontinuous nature of paleoecological data spanning many important periods in hominin evolution. Sediments from the Upper Burgi (1.98-1.87 Ma), KBS (1.87-1.56 Ma) and Okote (1.56-1.38 Ma) members of the Koobi Fora Formation at East Turkana in northern Kenya document an important time interval in the evolutionary history of the hominin genera Homo and Paranthropus. Although much attention has been paid to Upper Burgi and KBS member deposits, far less is known regarding the East Turkana paleoecosystem during Okote Member times. This study pairs spatially-resolved faunal abundance data with stable isotope geochemistry from mammalian enamel to investigate landscape-scale ecosystem variability during Okote Member times. We find that during this period 1) taxa within the East Turkana large mammal community were distributed heterogeneously across space, 2) the abundance of C3 and C4 vegetation varied between East Turkana subregions, and 3) the Karari subregion, an area with abundant evidence of hominin stone tool manufacture, had significantly more C3 vegetation than regions closer to the central axis of the Turkana Basin (i.e., Ileret and Koobi Fora). These findings indicate that the East Turkana paleoecosystem during the Okote Member was highly variable across space and provided a complex adaptive landscape for Pleistocene hominins.


Assuntos
Ecossistema , Fósseis , Mamíferos/classificação , Plantas/classificação , Animais , Biodiversidade , Evolução Biológica , Sedimentos Geológicos/análise , Hominidae , Quênia
5.
Gen Comp Endocrinol ; 242: 30-37, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-26718080

RESUMO

In fishes, maternal exposure to a stressor can influence offspring size and behavior. However, less is known about how maternal stress influences physiological processes in offspring, such as function of the hypothalamic-pituitary-interrenal (HPI) axis. We examined the impact of chronic maternal exposure to an acute chase stressor on the stress response/HPI activity of progeny in wild sockeye salmon (Oncorhynchus nerka). Resting plasma cortisol and brain preoptic area (POA) corticotropin-releasing factor (CRF) mRNA levels did not vary between offspring reared from undisturbed, control females and offspring reared from females exposed to the stressor. However, resting levels of POA glucocorticoid receptors (GR1 and GR2), and head kidney melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR), and cytochrome P450 side chain cleavage enzyme (P450scc) were elevated in offspring reared from stressor-exposed females. Offspring reared from stressor-exposed females had lower plasma cortisol levels 1-h after an acute chase stressor compared to cortisol levels in offspring reared from control females. In offspring reared from chased females, mRNA levels of genes associated with cortisol biosynthesis were reduced in the head kidney post-chase. In offspring reared from control females, mRNA levels in the head kidney did not vary pre- to post-chase. Together, the results of the present study suggest maternal programming of progeny with respect to baseline and stressor-induced mediators of HPI axis activity.


Assuntos
Rim Cefálico/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Exposição Materna , Salmão/fisiologia , Estresse Fisiológico , Animais , Hormônio Liberador da Corticotropina/metabolismo , Sistema Enzimático do Citocromo P-450/classificação , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Hidrocortisona/sangue , Fosfoproteínas , Receptor Tipo 2 de Melanocortina , Receptores de Glucocorticoides/sangue , Receptores de Glucocorticoides/metabolismo
6.
J Fish Dis ; 40(4): 453-477, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28188649

RESUMO

Microparasites play an important role in the demography, ecology and evolution of Pacific salmonids. As salmon stocks continue to decline and the impacts of global climate change on fish populations become apparent, a greater understanding of microparasites in wild salmon populations is warranted. We used high-throughput, quantitative PCR (HT-qRT-PCR) to rapidly screen 82 adult Chinook salmon from five geographically or genetically distinct groups (mostly returning to tributaries of the Fraser River) for 45 microparasite taxa. We detected 20 microparasite species, four of which have not previously been documented in Chinook salmon, and four of which have not been previously detected in any salmonids in the Fraser River. Comparisons of microparasite load to blood plasma variables revealed some positive associations between Flavobacterium psychrophilum, Cryptobia salmositica and Ceratonova shasta and physiological indices suggestive of morbidity. We include a comparison of our findings for each microparasite taxa with previous knowledge of its distribution in British Columbia.


Assuntos
Doenças dos Peixes/epidemiologia , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia , Salmão , Migração Animal , Animais , Colúmbia Britânica/epidemiologia , Feminino , Doenças dos Peixes/microbiologia , Doenças dos Peixes/parasitologia , Doenças dos Peixes/virologia , Masculino , Carga Parasitária/veterinária , Doenças Parasitárias em Animais/microbiologia , Doenças Parasitárias em Animais/virologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Fatores Sexuais
7.
J Environ Manage ; 187: 504-512, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27856036

RESUMO

The photo-degradation of the emerging contaminant antipyrine (AP) was studied and optimized in a novel photocatalytic spinning disc reactor (SDR). A heterogeneous process (UV/H2O2/TiO2) was used. TiO2 was immobilized on the surface of a glass disc using a sol-gel method. A factorial design of experiments followed by a Neural Networks fitting allowed the optimal conditions to be determined for treating 50 mg/L of AP. Under these conditions (pH = 4; [H2O2]0 = 1500 mg/L; disc speed = 500 rpm; flowrate = 25 mL/s), AP was completely degraded in 120 min and regeneration of the disc allowed 10 cycles with no loss in efficiency. The value of the apparent volumetric rate constant was found to be 6.9·10-4 s-1 with no apparent mass transfer limitation. Based on the main intermediates identified, a mechanism is proposed for antipyrine photodegradation: Firstly, cleavage of the NN bond of penta-heterocycle leads to the formation of two aromatic acids and N-phenylpropanamide. An attack to the CN bond in the latter compound produces benzenamine. Finally, the phenyl ring of the aromatic intermediates are opened and molecular organic acids are formed.


Assuntos
Antipirina/química , Titânio/química , Poluentes Químicos da Água/química , Purificação da Água , Catálise , Humanos , Fotólise , Raios Ultravioleta , Purificação da Água/métodos
8.
J Fish Biol ; 88(6): 2111-29, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27125426

RESUMO

In this study, animal-borne telemetry with temperature sensors was coupled with extensive habitat temperature monitoring in a dimictic reservoir, to test the following hypotheses: behavioural thermoregulation occurs throughout the year and temperature selection varies on a diel and seasonal basis, in a winter-specialist diel-migrating fish. Burbot Lota lota demonstrated nightly behavioural thermoregulation throughout the year, with a large seasonal shift between selection for very cold temperatures (<2° C) optimal for reproduction during the spawning period and selection for warmer temperatures (12-14° C) optimal for hunting and feeding during non-reproductive periods. During daylight hours, while L. lota avoided habitats warmer than optimal for reproduction and feeding during the spawning and non-reproductive periods, respectively, active selection was limited to selection for 4-6° C habitat during the prespawning period. Although behavioural thermoregulation explained the night-time migration, behavioural thermoregulation only partially explained daytime behaviour, indicating that diel migration is best explained by a combination of factors. Thus, thermal-habitat selection was a good predictor of night-time habitat occupancy in a diel-migrating species. Together, these results show that thermal-habitat selection by fishes may be important throughout the year and a more seasonally plastic behaviour than previously recognized.


Assuntos
Migração Animal , Ecossistema , Gadiformes/fisiologia , Animais , Comportamento Animal , Temperatura Baixa , Reprodução , Estações do Ano , Comportamento Sexual Animal , Temperatura
9.
J Fish Biol ; 86(1): 276-87, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25494933

RESUMO

Marine exit timing of sockeye salmon Oncorhynchus nerka populations on the Haida Gwaii Archipelago, British Columbia, Canada, is described, with specific focus on Copper Creek. Marine exit in Copper Creek occurs > 130 days prior to spawning, one of the longest adult freshwater residence periods recorded for any O. nerka population. Copper Creek presents an easy upstream migration, with mild water temperatures (7 to 14° C), short distance (13·1 km) and low elevation gain (41 m) to the lake where fish hold prior to spawning. An energetic model estimates that <1% of the initial energy reserve is required for upstream migration, compared with 62% for lake holding and 38% for reproductive development. Historical records suggest that it is unlikely that water temperature in any of the O.nerka streams in Haida Gwaii has ever exceeded the presumed temperature threshold (19° C) for early marine exit. Although it is not impossible that the thermal tolerance of Copper Creek O.nerka is very low, the data presented here appear inconsistent with thermal avoidance as an explanation for the early marine exit timing in Copper Creek and in three other populations on the archipelago with early marine exit.


Assuntos
Migração Animal/fisiologia , Salmão/fisiologia , Comportamento Sexual Animal/fisiologia , Temperatura , Animais , Colúmbia Britânica , Água Doce , Modelos Estatísticos , Periodicidade , Comportamento Predatório
10.
Oecologia ; 175(2): 493-500, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24619199

RESUMO

The environment mothers are exposed to has resonating effects on offspring performance. In iteroparous species, maternal exposure to stressors generally results in offspring ill-equipped for survival. Still, opportunities for future fecundity can offset low quality offspring. Little is known, however, as to how intergenerational effects of stress manifest in semelparous species with only a single breeding episode. Such mothers would suffer a total loss of fitness if offspring cannot survive past multiple life stages. We evaluated whether chronic exposure of female sockeye salmon (Oncorhynchus nerka) to a chase stressor impaired offspring performance traits. Egg size and early offspring survival were not influenced by maternal exposure to the repeated acute stressor. Later in development, fry reared from stressed mothers swam for shorter periods of time but possessed a superior capacity to re-initiate bouts of burst swimming. In contrast to iteroparous species, the mechanisms driving the observed effects do not appear to be related to cortisol, as egg hormone concentrations did not vary between stressed and undisturbed mothers. Sockeye salmon appear to possess buffering strategies that protect offspring from deleterious effects of maternal stress that would otherwise compromise progeny during highly vulnerable stages of development. Whether stressed sockeye salmon mothers endow offspring with traits that are matched or mismatched for survival in the unpredictable environment they encountered is discussed. This study highlights the importance of examining intergenerational effects among species-specific reproductive strategies, and across offspring life history to fully determine the scope of impact of maternal stress.


Assuntos
Exposição Materna , Salmão/fisiologia , Especificidade da Espécie , Estresse Fisiológico , Animais , Cruzamento , Meio Ambiente , Feminino , Estágios do Ciclo de Vida , Mães , Óvulo , Reprodução/genética , Natação
11.
J Dairy Sci ; 97(8): 5206-18, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24952782

RESUMO

The objective of this study was to compare calving traits, BCS, milk production, fertility, and survival of Holstein-Friesian (HF) and Norwegian Red (NR) dairy cattle in moderate-concentrate input systems. The experiment was conducted on 19 commercial Northern Ireland dairy farms, and involved 221 HF cows and 221 NR cows. Cows completed 5 lactations during the experiment, unless they died or were culled or sold. Norwegian Red cows had a lower calving difficulty score than HF cows when calving for the first and second time, but not for the third and fourth time. At first calving, the incidence of stillbirths for NR cows was 4%, compared with 13% for HF cows, whereas no difference existed between breeds in the proportion of calves born alive when calving for the second time. When calving for the first time, NR cows had a poorer milking temperament than HF cows, whereas milking temperament was unaffected by breed following the second calving. Holstein-Friesian cows had a higher full-lactation milk yield than NR cows, whereas NR cows produced milk with a higher milk fat and protein content. Full-lactation fat + protein yield was unaffected by genotype. Norwegian Red cows had a lower somatic cell score than HF cows during all lactations. Although NR cattle had a higher BCS than the HF cows during lactations 1 and 2, no evidence existed that the 2 genotypes either lost or gained body condition at different rates. Conception rates to first artificial insemination were higher with the NR cows during lactations 1 to 4 (57.8 vs. 40.9%, respectively), with 28.5% of HF cows and 11.8% of NR cows culled as infertile before lactation 6. A greater percentage of NR cows calved for a sixth time compared with HF cows (27.2 vs. 16.3%, respectively). In general, NR cows outperformed HF cows in traits that have been historically included in the NR breeding program.


Assuntos
Bovinos/fisiologia , Fertilidade , Lactação , Leite/metabolismo , Animais , Animais Recém-Nascidos , Cruzamento , Bovinos/genética , Indústria de Laticínios , Feminino , Genótipo , Longevidade , Parto
12.
Ecol Evol ; 14(5): e11333, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38694749

RESUMO

The goal of this study was to gather information about freshwater fishes in Letchworth State Park (42.615275° N, -77.992825° W), a portion of New York State-owned land located in the Genesee River Watershed that lacks known data about its fish diversity. Fish collection took place between 2017 and 2019 in the Genesse River upstream and downstream of the falls using electrofishing, gill, hoop, and seine netting. This was the first attempt at a comprehensive survey of this portion of the river, which allowed for a baseline to be established regarding fish biodiversity in the region. The updated total number of species found in this portion of the Genesee River was 25, 22 of which were newly identified downstream of the falls in Letchworth State Park. We encourage further collection and continuation of this survey with consistent sampling techniques to raise awareness about the importance of freshwater fish diversity in stream ecosystems across the globe.

13.
J Stud Alcohol Drugs ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38830016

RESUMO

OBJECTIVE: Measure prevalence and overlap of secondhand harms from other people's use of alcohol, cannabis, opioid, or other drugs and examine sociodemographic and other correlates of these secondhand harms. METHODS: This cross-sectional analysis used data from 7,799 respondents (51.6% female; 12.9% Black, 15.6% Hispanic/Latiné; mean age: 47.6) in the 2020 U.S. National Alcohol Survey. Secondhand harms included family/marriage difficulties, traffic accidents, vandalism, physical harm, and financial difficulties. Weighted prevalence estimates provided nationally representative estimates of these harms. Logistic regression assessed associations between individual characteristics and secondhand harms. RESULTS: Lifetime prevalence of secondhand harms from alcohol, cannabis, opioid, or other drugs was 34.2%, 5.5%, 7.6%, and 8.3%, respectively. There was substantial overlap among lifetime harms: almost 30% of those reporting secondhand alcohol harms also reported secondhand drug harms. Significant correlates of secondhand substance harms included female sex (alcohol, other drug); white (alcohol, opioid), American Indian/Alaska Native (opioid), and Black (cannabis) race/ethnicity; and separated/divorced/widowed marital status (opioid). Those reporting family history of alcohol problems had significantly higher odds of reporting secondhand harms across substance types. Individuals who reported frequent cannabis use had higher odds of reporting secondhand alcohol and opioid harms compared to those with no cannabis use, (aOR=1.55; aOR=2.38), but lower odds of reporting secondhand cannabis harms (aOR=0.51). CONCLUSIONS: Although less prevalent than secondhand alcohol harms, 14% of participants reported secondhand harms from someone else's drug use and frequently experienced secondhand harms attributed to multiple substances. Population-focused interventions are needed to reduce the total burden of alcohol and drug use.

14.
Conserv Physiol ; 12(1): coae034, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827188

RESUMO

Estimating the survival probability of animals released from fisheries can improve the overall understanding of animal biology with implications for fisheries management, conservation and animal welfare. Vitality indicators are simple visual measures of animal condition that change in response to stressors (like fisheries capture) and can be assessed to predict post-release survival. These indicators typically include immediate reflex responses which are typically combined into a score. Vitality indicators are straight-forward and non-invasive metrics that allow users to quantify how close (or far) an animal is from a normal, 'healthy' or baseline state, which in turn can be correlated with outcomes such as survival probability, given appropriate calibration. The literature on using vitality indicators to predict post-release survival of animals has grown rapidly over the past decade. We identified 136 papers that used vitality indicators in a fisheries context. These studies were primarily focused on marine and freshwater fishes, with a few examples using herptiles and crustaceans. The types of vitality indicators are diverse and sometimes taxa-specific (e.g. pinching leg of turtles, spraying water at nictitating membrane of sharks) with the most commonly used indicators being those that assess escape response or righting response given the vulnerability of animals when those reflexes are impaired. By presenting Pacific salmon fisheries as a case study, we propose a framework for using vitality indicators to predict survival across taxa and fisheries.

15.
J Dairy Sci ; 96(2): 854-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23219125

RESUMO

The objective was to compare pregnancy per AI (P/AI) with conventional (CON) or sex-sorted (SS) semen from a single sire within a fixed-time AI (FTAI) program designed for dairy heifers. Holstein heifers (n=240) were assigned to treatment (CON or SS) according to body weight and reproductive tract score. All heifers underwent FTAI by using the "Show-Me-Synch" protocol [controlled internal drug release (CIDR) insert from d 0 to 14 followed by PGF(2α) (25mg i.m.) 16d after insert removal (d 30) with GnRH (100 µg i.m.) and FTAI at 66 h after PGF(2α)]. A single professional technician performed the FTAI. Heifers were fitted with heat detection patches at PGF(2α) to characterize estrous response. Estrous response did not differ between CON (63/120; 53%) and SS (70/120; 58%) treatments. The CON heifers, however, achieved greater FTAI P/AI (82/120; 68%) compared with SS (45/120; 38%) heifers. The P/AI did not differ for CON heifers that exhibited or failed to exhibit estrus before FTAI [44/63 (70%) vs. 38/57(67%), respectively]. For SS heifers, however, those that exhibited estrus had greater P/AI compared with those that failed to exhibit estrus [32/70 (46%) vs. 13/50 (26%)]. Pregnancy per AI resulting from FTAI was greater for heifers that were inseminated with CON semen compared with those that received SS semen. The expression of estrus before FTAI did not affect P/AI when CON semen was used, whereas the P/AI with SS semen was greater for heifers detected in estrus. Further studies are required to develop strategies for using sex-sorted semen when inseminating heifers at predetermined fixed times on the basis of expression of estrus before FTAI.


Assuntos
Inseminação Artificial/veterinária , Sêmen/metabolismo , Pré-Seleção do Sexo/veterinária , Animais , Bovinos , Indústria de Laticínios/métodos , Detecção do Estro/métodos , Sincronização do Estro/métodos , Feminino , Inseminação Artificial/métodos , Masculino , Gravidez , Pré-Seleção do Sexo/métodos , Fatores de Tempo
16.
Nat Genet ; 15(1): 91-4, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8988176

RESUMO

A subset of familial and sporadic amyotrophic lateral sclerosis (ALS-a fatal disorder characterised by progressive motor neuron degeneration) cases are due to mutations in the gene encoding Cu,Zn superoxide dismutase (SOD1). Two mutations which have been successfully used to generate transgenic mice that develop an ALS-like syndrome are glycine 85 to arginine (G85R) and glycine 93 to alanine (G93A) with the mutant SOD1 allele overexpressed in a normal mouse genetic background. No ALS-like phenotype is observed in mice overexpressing wild-type SOD1 or mice without any SOD1 activity. These dominant mutations, which do not necessarily decrease SOD1 activity, may confer a gain of function that is selectively lethal to motor neurons. The yeast interaction trap system allowed us to determine whether these mutations in SOD1 caused novel protein interactions not observed with wild-type SOD1 and which might participate in the generation of the ALS phenotype. Two proteins, lysyl-tRNA synthetase and translocon-associated protein delta, interact with mutant forms of SOD1 but not with wild-type SOD1. The specificity of the interactions was confirmed by the coimmunoprecipitation of mutant SOD1 and the expressed proteins. These proteins are expressed in ventral cord, lending support to the relevance of this interaction to motor neuron disease.


Assuntos
Esclerose Lateral Amiotrófica/genética , Glicoproteínas de Membrana , Mutação , Proteínas/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Antígeno 12E7 , Esclerose Lateral Amiotrófica/enzimologia , Animais , Antígenos CD/metabolismo , Encéfalo/embriologia , Encéfalo/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Moléculas de Adesão Celular/metabolismo , Escherichia coli , Humanos , Lisina-tRNA Ligase/metabolismo , Camundongos , Dados de Sequência Molecular , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/genética , Saccharomyces cerevisiae , Medula Espinal/embriologia , Medula Espinal/metabolismo
17.
J Fish Biol ; 82(4): 1159-76, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23557297

RESUMO

Differences in thermal tolerance during embryonic development in Fraser River sockeye salmon Oncorhynchus nerka were examined among nine populations in a controlled common-garden incubation experiment. Forcing embryonic development at an extreme temperature (relative to current values) of 16° C, representing a future climate change scenario, significantly reduced survival compared to the more ecologically moderate temperature of 10° C (55% v. 93%). Survival at 14° C was intermediate between the other two temperatures (85%). More importantly, this survival response varied by provenance within and between temperature treatments. Thermal reaction norms showed an interacting response of genotype and environment (temperature), suggesting that populations of O. nerka may have adapted differentially to elevated temperatures during incubation and early development. Moreover, populations that historically experience warmer incubation temperatures at early development displayed a higher tolerance for warm temperatures. In contrast, thermal tolerance does not appear to transcend life stages as adult migration temperatures were not related to embryo thermal tolerance. The intra-population variation implies potential for thermal tolerance at the species level. The differential inter-population variation in thermal tolerance that was observed suggests, however, limited adaptive potential to thermal shifts for some populations. This infers that the intergenerational effects of increasing water temperatures may affect populations differentially, and that such thermally mediated adaptive selection may drive population, and therefore species, persistence.


Assuntos
Aclimatação , Salmão/embriologia , Temperatura , Migração Animal , Animais , Mudança Climática , Feminino , Genótipo , Masculino , Óvulo/fisiologia , Salmão/genética
18.
J Fish Biol ; 83(5): 1416-24, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24117961

RESUMO

Using a fixed-speed test, burst swimming performance was found to vary among nine populations of emergent sockeye salmon Oncorhynchus nerka fry reared in a common-garden environment. No consistent relationship was, however, detected between difficulty of fry migration (upstream v. downstream) to rearing areas and total burst swimming duration or bursting rate.


Assuntos
Migração Animal , Salmão/fisiologia , Natação , Animais , Colúmbia Britânica , Meio Ambiente , Salmão/genética
19.
Rev Sci Instrum ; 94(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37477553

RESUMO

We report on an ion trapping system for performing a novel form of cryogenic messenger spectroscopy with single molecule sensitivity. The system features a cryogenic radio-frequency ion trap loaded with single analyte molecules via a quadrupole mass filter. We demonstrate the ability to controllably attach inert gas particles to buffer gas cooled, trapped molecular ions. Sympathetic cooling by co-trapped, laser cooled 88Sr+ further reduces the translational temperature of trapped molecules to the millikelvin regime. We verify the presence of cryogenic "tags" via non-destructive optical mass spectrometry and selectively remove these adducts by resonantly driving vibrational transitions in the tagged molecular ions. This enables us to derive the vibrational spectrum of a single analyte molecule from the frequency dependence of the tag detachment rate. We have demonstrated these capabilities by measuring transitions in the C-H stretching region for single cationic fragments of both indole (C8H7N) and 1,3-benzodioxole (C6H4O2CH2). These capabilities are not reliant on a specific molecular level structure and thus constitute a general, non-destructive method for vibrational spectroscopy of individual molecular ions.

20.
Aquat Toxicol ; 265: 106772, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38039693

RESUMO

In a previous study, adaptive responses to a single polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BaP), were identified in brown bullhead (Ameiurus nebulosus) captured from contaminated sites across the Great Lakes. The tumor suppressor p53 and phase I toxin metabolizing CYP1A genes showed a elevated and refractory response, respectively, up to the F1 generation (Williams and Hubberstey, 2014). As an extension to the first study, bullhead were exposed to sediment collected from sites along the Detroit River to see if these adaptive responses are attainable when fish from a contaminated site are exposed to a mixture of contaminants, instead of a single compound. p53 and CYP1A proteins were measured again with the addition of phase II glutathione-s-transferase (GST) activity in the present study. Three treatment groups were measured: acute (treated immediately), cleared (depurated for three months and subsequent treatment), and farm raised F1 offspring. All three treatment groups were exposed to clean and contaminated sediment for 24 and 96 h. Acute fish from contaminated sites exposed to contaminated sediment revealed an initial elevated p53 response that did not persist in fish after long-term contaminated sediment exposure. Acute fish from contaminated sites exposed to contaminated sediment revealed refractory CYP1A expression, which disappeared in cleared fish and whose F1 response overlapped with clean site F1 offspring. Decreasing GST activity was evident in both clean and contaminated fish over time, and only clean site fish responded to long-term contaminated sediment deliberately with increasing GST activity. Because p53 and CYP1A gene expression and GST activity responses did not overlap between contaminated fish treatment groups, our study suggests that contaminated fish have acclimated to the contaminants present in their environments and no evidence of adaptation could be detected within these biomarkers.


Assuntos
Ictaluridae , Poluentes Químicos da Água , Animais , Ictaluridae/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Rios , Poluentes Químicos da Água/toxicidade , Aclimatação
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