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OBJECTIVE: Cholestatic pruritus in primary biliary cholangitis (PBC) reduces patients' health-related quality of life (HRQoL). Despite this, existing research suggests that pruritus is under-recorded in patients' health records. This study assessed the extent to which pruritus was recorded in medical records of patients with PBC as compared with patient-reported pruritus, and whether patients reporting mild itch were less likely to have pruritus recorded. We also evaluated clinico-demographic characteristics and HRQoL of patients with medical record-documented and patient-reported pruritus. DESIGN: This cross-sectional study used clinical information abstracted from medical records, together with patient-reported (PBC-40) data from patients with PBC in the USA enrolled in the PicnicHealth cohort. Medical record-documented pruritus was classified as 'recent' (at, or within 12 months prior to, enrolment) or 'ever' (at, or any point prior to, enrolment). Patient-reported pruritus (4-week recall) was assessed using the first PBC-40 questionnaire completed on/after enrolment; pruritus severity was classified by itch domain score (any severity: ≥1; clinically significant itch: ≥7). Patient clinico-demographic characteristics and PBC-40 domain scores were described in patients with medical record-documented and patient-reported pruritus; overlap between groups was evaluated. Descriptive statistics were reported. RESULTS: Pruritus of any severity was self-reported by 200/225 (88.9%) patients enrolled; however, only 88/225 (39.1%) had recent medical record-documented pruritus. Clinically significant pruritus was self-reported by 120/225 (53.3%) patients; of these, 64/120 (53.3%) had recent medical record-documented pruritus. Patients reporting clinically significant pruritus appeared to have higher mean scores across PBC-40 domains (indicating reduced HRQoL), versus patients with no/mild patient-reported pruritus or medical-record documented pruritus. CONCLUSION: Compared with patient-reported measures, pruritus in PBC is under-recorded in medical records and is associated with lower HRQoL. Research based only on medical records underestimates the true burden of pruritus, meaning physicians may be unaware of the extent and impact of pruritus, leading to potential undertreatment.
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Cirrosis Hepática Biliar , Humanos , Cirrosis Hepática Biliar/complicaciones , Cirrosis Hepática Biliar/epidemiología , Calidad de Vida , Estudios Transversales , Registros Médicos , Prurito/epidemiología , Prurito/complicaciones , Prurito/tratamiento farmacológicoRESUMEN
In 2011, a historic Supreme Court decision mandated that the state of California substantially reduce its prison population to alleviate overcrowding, which was deemed so severe as to preclude the provision of adequate healthcare. To comply, California passed the Public Safety Realignment Act (Assembly Bill [AB] 109), representing the largest ever court-ordered reduction of a prison population in U.S. history. AB109 was successful in reducing the state prison population; however, although the policy was precipitated by inadequate healthcare in state prisons, no studies have examined its effects on prisoner health. As other states grapple with overcrowded prisons and look to California's experience with this landmark policy, understanding how it may have impacted prisoner health is critical. We sought to evaluate the effects of AB109 on prison mortality and assess the extent to which policy-induced changes in the age distribution of prisoners may have contributed to these effects. To do so, we used prison mortality data from the Bureau of Justice Statistics and the California Deaths in Custody reporting program and prison population data from the National Corrections Reporting Program to examine changes in overall prison mortality, the age distribution of prisoners, and age-adjusted prison mortality in California relative to other states before and after the implementation of AB109. Following AB109, California prisons experienced an increase in overall mortality relative to other states that attenuated within three years. Over the same period, California experienced a greater upward shift in the age distribution of its prisoners relative to other states, suggesting that the state's increase in overall mortality may have been driven by this change in age distribution. Indeed, when accounting for this differential change in age distribution, mortality among California prisoners exhibited a greater reduction relative to other states in the third year after implementation. As other states seek to reduce their prison populations to address overcrowding, assessments of California's experience with AB109 should consider this potential improvement in age-adjusted mortality.
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Prisioneros , Humanos , Distribución por Edad , Políticas , Instituciones de Salud , California/epidemiología , PrisionesRESUMEN
Chronic pain is common among persons living with HIV and changes in opioid prescribing practices may complicate HIV care management. Using medical record data from a retrospective cohort study conducted January 1, 2012 to June 30, 2019 for 300 publicly insured HIV-positive primary care patients prescribed opioids for chronic non-cancer pain in San Francisco, we examined associations between opioid dose changes and both time to disengagement from HIV care and experiencing virologic failure using logistic regression. Discontinuation of prescribed opioids was associated with increased odds of disengagement in care at 3, 6, and 9 months after discontinuation. There were no associations with virologic failure. Providers and policy makers must weigh impacts on HIV care when implementing necessary changes in opioid prescribing.
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Dolor Crónico , Infecciones por VIH , Analgésicos Opioides/uso terapéutico , Dolor Crónico/complicaciones , Dolor Crónico/tratamiento farmacológico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Pautas de la Práctica en Medicina , Estudios RetrospectivosRESUMEN
Introduction: People with opioid use disorder (OUD) have high rates of discharge against medical advice from the hospital. Interventions for addressing these patient-directed discharges (PDDs) are lacking. We sought to explore the impact of methadone treatment for OUD on PDD. Methods: Using electronic record and billing data from an urban safety-net hospital, we retrospectively examined the first hospitalization on a general medicine service for adults with OUD from January 2016 through June 2018. Associations with PDD compared to planned discharge were examined using multivariable logistic regression. Administration patterns of maintenance therapy versus new in-hospital initiation of methadone were examined using bivariate tests. Results: During the study time period, 1,195 patients with OUD were hospitalized. 60.6% of patients received medication for OUD, of which 92.8% was methadone. Patients who received no treatment for OUD had a 19.1% PDD rate while patients initiated on methadone in-hospital had a 20.5% PDD rate and patients on maintenance methadone during the hospitalization had a 8.6% PDD rate. In multivariable logistic regression, methadone maintenance was associated with lower odds of PDD compared to no treatment (aOR 0.53, 95% CI 0.34-0.81), while methadone initiation was not (aOR 0.89, 95% CI 0.56-1.39). About 60% of patients initiated on methadone received 30 mg or less per day. Conclusions: In this study sample, maintenance methadone was associated with nearly a 50% reduction in the odds of PDD. More research is needed to assess the impact of higher hospital methadone initiation dosing on PDD and if there is an optimal protective dose.
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AIMS: To evaluate associations between new types of buprenorphine waivers (nurse practitioner and physician assistant [NP/PA]; 275-patient limit [MD/DO-275]) and both buprenorphine prescribing and health outcomes. METHODS: Using comprehensive county-level data from California 2010-2018, we modeled quarterly associations between numbers of NP/PA and MD/DO-275 waivers and rates of buprenorphine prescribing, opioid-related deaths, emergency department (ED) visits, and hospitalizations among all counties and separately among metropolitan and nonmetropolitan counties using Poisson regression models with county and quarter fixed effects and adjusting for time-varying covariates. RESULTS: Each additional NP/PA and MD/DO-275 waiver was associated with a 2.6% (95%CI: 1.1-4.1%) and 5.8% (4.1-7.4%) increase in buprenorphine prescribing among nonmetropolitan counties, respectively. Each additional MD/DO-275 waiver was associated with a 2.8% (1.0%-4.6%) increase in buprenorphine among metropolitan counties. There were no statistically significant associations between NP/PA waivers and buprenorphine prescribing among metropolitan counties or among either waiver type and opioid-related health outcomes. CONCLUSIONS: NP/PA waivers were associated with increased buprenorphine prescribing among nonmetropolitan counties and MD/DO-275 waivers were associated with increased buprenorphine prescribing among both metropolitan and nonmetropolitan counties.
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Buprenorfina , Trastornos Relacionados con Opioides , Analgésicos Opioides/uso terapéutico , Buprenorfina/uso terapéutico , Humanos , Tratamiento de Sustitución de Opiáceos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiología , Evaluación de Resultado en la Atención de Salud , Estados UnidosRESUMEN
BACKGROUND: After decades of liberal opioid prescribing, multiple efforts have been made to reduce reliance upon opioids in clinical care. Little is known about the effects of opioid prescribing policies on outcomes beyond opioid prescribing. OBJECTIVE: To evaluate the combined effects of multiple opioid prescribing policies implemented in a safety-net primary care clinic in San Francisco, CA, in 2013-2014. DESIGN: Retrospective cohort study and conditional difference-in-differences analysis of nonrandomized clinic-level policies. PATIENTS: 273 patients prescribed opioids for chronic non-cancer pain in 2013 at either the treated (n=151) or control clinic (n=122) recruited and interviewed in 2017-2018. INTERVENTIONS: Policies establishing standard protocols for dispensing opioid refills and conducting urine toxicology testing, and a new committee facilitating opioid treatment decisions for complex patient cases. MAIN MEASURES: Opioid prescription (active prescription, mean dose in morphine milligram equivalents [MME]) from electronic medical charts, and heroin and opioid analgesics not prescribed to the patient (any use, use frequency) from a retrospective interview. KEY RESULTS: The interventions were associated with a reduction in mean prescribed opioid dose in the first three post-policy years (year 1 conditional difference-in-differences estimate: -52.0 MME [95% confidence interval: -109.9, -10.6]; year 2: -106.2 MME [-195.0, -34.6]; year 3: -98.6 MME [-198.7, -23.9]; year 4: -72.6 MME [-160.4, 3.6]). Estimates suggest a possible positive association between the interventions and non-prescribed opioid analgesic use (year 3: 5.2 absolute percentage points [-0.1, 11.2]) and use frequency (year 3: 0.21 ordinal frequency scale points [0.00, 0.47]) in the third post-policy year. CONCLUSIONS: Clinic-level opioid prescribing policies were associated with reduced dose, although the control clinic achieved similar reductions by the fourth post-policy year, and the policies may have been associated with increased non-prescribed opioid analgesic use. Clinicians should balance the urgency to reduce opioid prescribing with potential harms from rapid change.
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Analgésicos Opioides , Dolor Crónico , Analgésicos Opioides/efectos adversos , Dolor Crónico/tratamiento farmacológico , Dolor Crónico/epidemiología , Prescripciones de Medicamentos , Humanos , Políticas , Pautas de la Práctica en Medicina , Atención Primaria de Salud , Estudios RetrospectivosRESUMEN
OBJECTIVES: Describe clinical and demographic associations with inpatient medication for opioid use disorder (MOUD) initiation on general medicine services and to examine associations between inpatient MOUD initiation by generalists and subsequent patient healthcare utilization. METHODS: This is a retrospective study using medical record data from general medicine services at an urban safety-net hospital before an inpatient addiction consultation service. The patients were adults hospitalized for acute medical illness who had an opioid-related ICD-10 code associated with the visit. Associations with MOUD initiation were assessed using multivariable logistic regression. Hospital readmission, emergency department use, linkage to opioid treatment programs (OTP), and mortality at 30- and 90-days postdischarge were compared between those with and without hospital MOUD initiation using χ2 tests. RESULTS: Of 1,284 hospitalized patients with an opioid-related code, 59.81% received MOUD and 31.38% of these were newly initiated in-hospital. In multivariable logistic regression, Black race, mood disorder, psychotic disorder, and alcohol use disorder were negatively associated with MOUD initiation, while being aged 25-34, having a moderate hospital severity of illness score, and experiencing homelessness were positively associated. There were no bivariate associations between MOUD initiation and postdischarge emergency department use, hospital readmission, or mortality at 30- and 90-days, but those initiated on MOUD were more likely to present to an OTP within 90âdays (30.57% vs 12.80%, Pâ<â0.001). CONCLUSIONS: MOUD prescribing by inpatient generalists may help to increase the number of patients on treatment for opioid use disorder after hospital discharge. More research is needed to understand the impact of inpatient MOUD treatment without addiction specialty consultation.
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Analgésicos Opioides , Trastornos Relacionados con Opioides , Adulto , Cuidados Posteriores , Analgésicos Opioides/uso terapéutico , Humanos , Pacientes Internos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Alta del Paciente , Estudios RetrospectivosRESUMEN
California's Mental Health Services Act (MHSA) substantially expanded funding of county mental health services through a state tax, and led to broad prevention efforts and intensive services for individuals experiencing serious mental disorders. We estimated the associations between MHSA and mortality due to suicide, homicide, and acute effects of alcohol. Using annual cause-specific mortality data for each US state and the District of Columbia from 1976-2015, we used a generalization of the quasi-experimental synthetic control method to predict California's mortality rate for each outcome in the absence of MHSA using a weighted combination of comparison states. We calculated the association between MHSA and each outcome as the absolute difference and percentage difference between California's observed and predicted average annual rates over the postintervention years (2007-2015). MHSA was associated with modest decreases in average annual rates of homicide (-0.81/100,000 persons, corresponding to a 13% reduction) and mortality from acute alcohol effects (-0.35/100,000 persons, corresponding to a 12% reduction). Placebo test inference suggested that the associations were unlikely to be due to chance. MHSA was not associated with suicide. Protective associations with mortality due to homicide and acute alcohol effects provide evidence for modest health benefits of MHSA at the population level.
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Consumo de Bebidas Alcohólicas/mortalidad , Homicidio/estadística & datos numéricos , Trastornos Mentales/mortalidad , Servicios de Salud Mental/estadística & datos numéricos , Salud Poblacional/estadística & datos numéricos , Suicidio/estadística & datos numéricos , Consumo de Bebidas Alcohólicas/prevención & control , California/epidemiología , Causas de Muerte , Implementación de Plan de Salud , Homicidio/prevención & control , Humanos , Trastornos Mentales/prevención & control , Servicios de Salud Mental/legislación & jurisprudencia , Estados Unidos/epidemiología , Prevención del SuicidioRESUMEN
BACKGROUND: Understanding whether International Classification of Disease, 10th Revision, Clinical Modification (ICD-10-CM) codes can be used to accurately detect substance use can inform their use in future surveillance and research efforts. METHODS: Using 2015-2018 data from a retrospective cohort study of 602 safety-net patients prescribed opioids for chronic non-cancer pain, we calculated the sensitivity and specificity of using ICD-10-CM codes to detect illicit substance use compared to retrospective self-report by substance (methamphetamine, cocaine, opioids [heroin or non-prescribed opioid analgesics]), self-reported use frequency, and type of healthcare encounter. RESULTS: Sensitivity of ICD-10-CM codes for detecting self-reported substance use was highest for methamphetamine (49.5 % [95 % confidence interval: 39.6-59.5 %]), followed by cocaine (44.4 % [35.8-53.2 %]) and opioids (36.3 % [28.8-44.2 %]); higher for participants who reported more frequent methamphetamine (intermittent use: 27.7 % [14.6-42.6 %]; ≥weekly use: 67.2 % [53.7-79.0 %]) and opioid use (intermittent use: 21.4 % [13.2-31.7 %]; ≥weekly use: 52.6 % [40.8-64.2 %]); highest for outpatient visits (methamphetamine: 43.8 % [34.1-53.8 %]; cocaine: 36.8 % [28.6-45.6 %]; opioids: 33.1 % [25.9-41.0 %]) and lowest for emergency department visits (methamphetamine: 8.6 % [4.0-15.6 %]; cocaine: 5.3 % [2.1-10.5 %]; opioids: 6.3 % [3.0-11.2 %]). Specificity was highest for methamphetamine (96.4 % [94.3-97.8 %]), followed by cocaine (94.0 % [91.5-96.0 %]) and opioids (85.0 % [81.3-88.2 %]). CONCLUSIONS: ICD-10-CM codes had high specificity and low sensitivity for detecting self-reported substance use but were substantially more sensitive in detecting frequent use. ICD-10-CM codes to detect substance use, particularly those from emergency department visits, should be used with caution, but may be useful as a lower-bound population measure of substance use or for capturing frequent use among certain patient populations.
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Drogas Ilícitas , Clasificación Internacional de Enfermedades , Trastornos Relacionados con Sustancias/diagnóstico , Adulto , Analgésicos Opioides/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Cocaína , Servicio de Urgencia en Hospital , Femenino , Heroína , Humanos , Masculino , Metanfetamina , Persona de Mediana Edad , Trastornos Relacionados con Opioides/tratamiento farmacológico , Estudios Retrospectivos , Autoinforme , Sensibilidad y EspecificidadRESUMEN
Interpersonal violence is a major global public health problem, and the burden of nonfatal assault injuries is far greater than that of homicides. To understand trends and inform prevention priorities, we sought to describe nonfatal assault injury trends across demographic groups from 2005 to 2015 in California, USA. Comprehensive hospitalization and emergency department discharge records were used to estimate annual rates of nonfatal assault injury overall and by means and age group and age-standardized annual rates by race/ethnicity, gender, and county. The overall rate of assault injury was stable in California from 2005 to 2015 (mean = 364 per 100,000), but there was substantial heterogeneity across demographic groups, including increases among African Americans (900 to 1,194), American Indian/Alaskan Natives (423 to 572), older individuals (age 25-29 = 697 to 727; 30-39 = 495 to 557; 40-49 = 352 to 404; 50-59 = 194 to 313; 60+ = 66 to 106), and women (199 to 252). Assault injury rates increased among several demographic groups, warranting the attention of professionals involved in violence prevention efforts. Epidemiologic examination to better understand causes of increases can inform prevention efforts. Similar analyses should be applied to other settings to determine how broadly these patterns are observed.
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Víctimas de Crimen , Heridas y Lesiones , Adulto , California , Etnicidad , Femenino , Homicidio , Humanos , ViolenciaRESUMEN
As global temperatures continue to rise, so too will the nest temperatures of many species of turtles. Yet for most turtle species, including the estuarine diamondback terrapin (Malaclemys terrapin), there is limited information on embryonic sensitivity to elevated temperature. We incubated eggs of M. terrapin at three, mean temperatures (31, 34, 37 °C) under two thermal exposure regimes (constant or semi-naturally fluctuating temperature) and measured hatching success, developmental rate, and hatchling size. Hatching success was 100% at 31 °C and 67% at 34 °C, respectively; at 37 °C, all eggs failed early in the incubation period. These values were unaffected by exposure regime. The modeled LT50 (temperature that was lethal to 50% of the test population) was 34.0 °C in the constant and 34.2 °C in the fluctuating thermal regime, reflecting a steep decline in survival between 33 and 35 °C. Hatchlings having been incubated at a constant 34 °C hatched sooner than those incubated at 31 °C under either constant or fluctuating temperature. Hatchlings were smaller in straight carapace length (CL) and width after having been incubated at 34 °C compared to 31 °C. Larger (CL) hatchlings resulted from fluctuating temperature conditions relative to constant temperature conditions, regardless of mean temperature. Based upon recent temperatures in natural nests, the M. terrapin population studied here appears to possess resiliency to several degrees of elevated mean nest temperatures, beyond which, embryonic mortality will likely sharply increase. When considered within the mosaic of challenges that Maryland's M. terrapin face as the climate warms, including ongoing habitat losses due to sea level rise and impending thermal impacts on bioenergetics and offspring sex ratios, a future increase in embryonic mortality could be a critical factor for a population already experiencing ecological and physiological challenges due to climate change.
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Cambio Climático , Embrión no Mamífero/fisiología , Temperatura , Tortugas/fisiología , Animales , Femenino , CigotoRESUMEN
BACKGROUND: Single room occupancy (SRO) buildings, also known as residential hotels, are a form of affordable housing common to cities in North America, and residents of these buildings face elevated rates of substance use, physical and mental multimorbidity, and mortality. Identifying distinct populations at greater risk of overdose death is crucial to the planning of interventions aiming to reduce drug-related mortality, yet no studies have assessed the population burden of overdose mortality among SRO residents. The present study quantifies and characterizes drug overdose mortality among residents of SRO buildings in a large U.S. city. METHODS: We used mortality records and a database of SRO buildings to calculate rate ratios comparing overdose mortality due to opioids, cocaine, and methamphetamine among SRO residents and non-SRO residents in San Francisco, CA 2010-2017 and assessed bivariate differences in decedent and death location characteristics between SRO resident and other overdose decedents. RESULTS: There were 1,551 overdose deaths during the study period, with an overall rate of 21.3 per 100,000 residents (95%CIâ¯=â¯20.2-22.6). The rate among SRO residents (278.7, 95%CIâ¯=â¯252.9-306.5) was 19.3 (95%CIâ¯=â¯17.1-21.7) times that of non-SRO residents (21.3, 95%CIâ¯=â¯20.2-22.6). An additional 79 (5%) deaths among non-residents occurred in SRO buildings, and 86% of SRO resident decedents died at home compared to 64% of non-SRO residents (pâ¯<â¯0.05). CONCLUSIONS: Overdose mortality was substantially higher among SRO residents, who were also more likely to die from overdose at home, which highlights the need for resources and targeted interventions directed towards residents of SRO buildings.
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Sobredosis de Droga/mortalidad , Instituciones Residenciales/estadística & datos numéricos , Adulto , Analgésicos Opioides/toxicidad , Cocaína/toxicidad , Femenino , Humanos , Masculino , Metanfetamina/toxicidad , Persona de Mediana Edad , San Francisco/epidemiología , Factores de Tiempo , Adulto JovenRESUMEN
I estimated standard metabolic rates (SMR) using measurements of oxygen consumption rates of embryos and unfed, resting hatchlings of the diamondback terrapin (Malaclemys terrapin) three times during embryonic development and twice during the early post-hatching period. The highest observed SMRs occurred during mid to late embryonic development and the early post-hatching period when hatchlings were still reliant on yolk reserves provided by the mother. Hatchlings that were reliant on yolk displayed per capita SMR 135 % higher than when measured 25 calendar days later after they became reliant on exogenous resources. The magnitude of the difference in hatchling SMR between yolk-reliant and exogenously feeding stages was much greater than that attributed to costs of digestion (specific dynamic action) observed in another emydid turtle, suggesting that processing of the yolk was not solely responsible for the observed difference. The pre-feeding period of yolk reliance of hatchlings corresponds with the period of dispersal from the nesting site, suggesting that elevated SMR during this period could facilitate dispersal activities. Thus, I hypothesize that the reduction in SMR after the development of feeding behaviors may reflect an energy optimization strategy in which a high metabolic expenditure in support of development and growth of the embryo and dispersal of the hatchling is followed by a substantial reduction in metabolic expenditure coincident with the individual becoming reliant on exogenous resources following yolk depletion.
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Metabolismo Basal , Tortugas/metabolismo , Animales , Animales Recién Nacidos/metabolismo , Animales Recién Nacidos/fisiología , Metabolismo Basal/fisiología , Embrión no Mamífero/metabolismo , Embrión no Mamífero/fisiología , Metabolismo Energético/fisiología , Femenino , Tortugas/embriología , Tortugas/crecimiento & desarrollo , Tortugas/fisiologíaRESUMEN
Climate change is bringing about increased temperatures of amphibian habitats throughout the world, where ectothermic larvae will experience elevated respiratory (metabolic) energy demands. We compared the acute, thermal respiratory response ("TRR") of four species of sympatric larval amphibians (Lithobates sphenocephalus, L. catesbeianus, Scaphiopus holbrookii, and Hyla chrysoscelis) to determine species-specific differences in the rate at which metabolic energy requirements increase with temperature. The TRR, the slope of the relationship between respiration rate and temperature within critical thermal limits, varied significantly among species such that the absolute, per capita change in metabolic energy requirement as temperature increased was greater for L. sphenocephalus and L. catesbeianus than for H. chrysoscelis and S. holbrookii. This was also reflected in the temperature coefficients (Q10,18.5-25.5), which ranged from 1.77 (S. holbrookii) to 2.70 (L. sphenocephalus) for per capita respiration rates. Our results suggest that L. sphenocephalus and L. catesbeianus will experience a more rapid increase in energetic requirements as temperature increases relative to the other species, possibly magnifying their influences on the resource pool. There is a critical paucity of information on the metabolic responses of most larval amphibians across a range of temperatures, despite that this relationship dictates the magnitude of the priority investment of assimilated energy in respiration, thus shaping the energetic economy of the individual. A broader knowledge of species-specific TRRs, combined with research to determine thermal acclimatory or adaptive potentials over chronic time scales, will provide a framework for evaluating whether asymmetric, climate-mediated differences in energetic demands among species could ultimately influence larval amphibian ecology in a warmer future.
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Anuros/fisiología , Cambio Climático , Frecuencia Respiratoria , Temperatura , Animales , Larva/fisiologíaRESUMEN
Larval gray tree frogs (Hyla chrysoscelis) were exposed to inorganic Se (SeO2) added to the diet (10.2 and 86.3 ug/g dw) and monitored for accumulation and effect. Background concentrations of Hg were also measured in food and carcasses to assess possible effects of Se on Hg accumulation. Selenium was accumulated in a dose dependent manner, and life stages did not differ. No effects of Se exposure were observed on survival, growth, or time to metamorphosis. Mercury concentrations in carcasses, resulting from background concentrations in food, were significantly affected by the presence of Se. In the high Se treatment, Hg concentrations were significantly decreased relative to those in the low Se treatment and the control. Our study suggests that exposure to inorganic Se as SeO2 at the concentrations tested do not elicit adverse biological effects, but exposure to relatively high concentrations of Se may reduce accumulation of Hg from food.
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Anuros/metabolismo , Mercurio/metabolismo , Selenio/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Dieta/estadística & datos numéricos , Monitoreo del Ambiente , Larva/efectos de los fármacos , Metamorfosis Biológica/efectos de los fármacos , Selenio/análisis , Compuestos de Selenio/metabolismoRESUMEN
Non-genetic maternal effects, operating through a female's physiology or behavior, can influence offspring traits and performance. Here we examined potential maternal influences on metabolic rates (MR) of offspring in an estuarine turtle, the diamondback terrapin (Malaclemys terrapin). Females and their eggs were collected from the field and the eggs incubated in the laboratory for subsequent measurement of MR of females, late-stage embryos, newly-hatched individuals that were nutritionally dependent on yolk, and older hatchlings that had depleted their yolk reserves and thus were independent of energetic contributions from the female. Female identity significantly affected MR of yolk-dependent hatchlings but, after yolk was depleted, MR of offspring converged and no longer reflected the maternal influence. Offspring from different females also differed in size, which influenced offspring MR and growth, but there was no correlation between female MR or size and offspring traits. MR of the older, yolk-independent hatchlings was lower overall than yolk-dependent hatchlings but correlated positively with growth rates and prior developmental rate (e.g. negatively correlated with time to hatching). Unlike another turtle species (snapping turtles), in which maternally-related differences in offspring MR were retained after yolk depletion, the maternal influence on offspring MR in diamondback terrapins is limited to early hatchling development and growth. The transient nature of the maternal effect, which was present only during the period that hatchlings were metabolizing yolk, suggests that variation among females in the composition of yolk deposited in eggs could be responsible for the differences observed in this study.
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Huevos , Metabolismo Energético , Tortugas/fisiología , Saco Vitelino , Animales , Tamaño de la Nidada , Femenino , Crecimiento , Tortugas/embriología , Tortugas/metabolismoRESUMEN
Juvenile red-eared sliders (Trachemys scripta elegans) and snapping turtles (Chelydra serpentina) were fed food dosed with brominated diphenyl ether-47 (BDE-47) or BDE-99 for 6 mo beginning approximately 9 mo posthatch. During the exposure period, measurements of growth, bioenergetics, and behavior were made; thyroid function and accumulation were quantified postexposure. Whole-body concentrations of both congeners were lower in red-eared sliders compared with snapping turtles after 6 mo of exposure. Snapping turtles receiving BDE-47 had significantly elevated standard metabolic rates after 3 mo and 4 mo of exposure (p = 0.014 and p = 0.019, respectively). When exposed to BDE-99, red-eared sliders were slower to right themselves after having been inverted (p < 0.0001). Total glandular thyroxine concentrations were significantly reduced in red-eared sliders exposed to BDE-47 (mean control, 8080 ng/g; mean BDE-47, 5126 ng/g; p = 0.034). These results demonstrate that dietary exposure to BDE-47 and BDE-99 can elicit a suite of responses in 2 species of turtles, but that the red-eared slider appears to be a more sensitive species to the measured end points.
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Conducta Animal/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Éteres Difenilos Halogenados/toxicidad , Glándula Tiroides/efectos de los fármacos , Tortugas/metabolismo , Animales , Exposición a Riesgos Ambientales , Cromatografía de Gases y Espectrometría de Masas , Éteres Difenilos Halogenados/análisis , Glándula Tiroides/metabolismo , Tiroxina/metabolismoRESUMEN
Advances have been made recently in assessing accumulation and effects of coal combustion residues (CCR). I provide a brief review of recent advancements, provide a tabulated summary of results of recent work, and put forth recommendations for future studies. One advancement is that mercury accumulation has begun to receive (limited) attention, whereas it had rarely been considered in the past. Additionally, some constituents of CCR have been shown to be accumulated by adults and transferred to offspring, sometimes compromising offspring health. Studies have demonstrated that amphibians, possessing complex life cycles, may accumulate and transfer some contaminants to terrestrial systems. Some study has been given to molecular and cellular effects of CCR exposure, although these studies have been limited to invertebrates. Population models have also been applied to CCR affected systems and have shown that CCR may affect animal populations under some conditions. In light of these advancements, there are several topics that require further assessment. First, more attention to Hg and its dynamics in CCR affected systems is warranted. Hg can be highly accumulative and toxic under some conditions and may interact with other components of CCR (notably Se), perhaps altering accumulation and effects of the contaminant mixtures. Second, further investigation of maternal transfer and effects of CCR contaminants need to be conducted. These studies could benefit from incorporation of quantitative models to project impacts on populations. Finally, more attention to the organic constituents of CCR (PAHs) is required, as a focus on inorganic compounds only may restrict our knowledge of contaminant dynamics and effects as a whole. While further studies will shed light on some chemical and biological nuances of exposure and effect, information available to date from numerous study sites implicates CCR as a bulk effluent that presents risks of bioaccumulation and effects on organisms in aquatic systems.
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Carbón Mineral , Monitoreo del Ambiente , Metales/metabolismo , Eliminación de Residuos/métodos , Oligoelementos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Anfibios/metabolismo , Animales , Sedimentos Geológicos/química , Residuos Industriales , Invertebrados/metabolismo , Metales/análisis , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Maternal transfer of methylmercury (MeHg) to eggs is an important exposure pathway for developing offspring. However, our understanding of this process is limited, particularly in estuarine fish. We conducted a 91-day chronic laboratory exposure of Cyprinodon variegatus to four concentrations of dietary MeHg ranging from 0.04 to 9.90 µg g(-1) dw. Juvenile fish were fed a preoogenesis MeHg diet for 28 days, after which the diet was switched to a diet enriched with Me(199)Hg, spanning the period of oogenesis, allowing us to differentiate between mercury stored in female tissues and mercury assimilated from the maternal diet during oogenesis. We found that both maternal body burden and clutch size were strong predictors of egg Hg content. A constant percentage of preoogenesis Hg was transferred to eggs in each treatment. Additionally, preoogenesis Hg and during-oogenesis Hg were transferred proportionally to eggs, suggesting that both female tissues and the maternal diet during oogenesis are significant sources of Hg.
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Peces Killi/metabolismo , Exposición Materna , Compuestos de Metilmercurio/metabolismo , Óvulo/metabolismo , Animales , Cyprinidae , Dieta , Femenino , Peces/metabolismo , Isótopos/metabolismo , Mercurio/análisis , Mercurio/metabolismo , Isótopos de Mercurio/análisis , Óvulo/químicaRESUMEN
We performed an experiment in which larval gray tree frogs (Hyla chrysoscelis) were raised through metamorphosis on diets increased with a suite of elements associated with coal combustion residues (silver [Ag], arsenic [As], cadmium [Cd], chromium [Cr], copper [Cu], mercury [Hg], lead [Pb], selenium [Se], vanadium [V], and zinc [Zn]) at "low" and "high" concentrations. We quantified accumulation of metals at three life stages (mid-larval development, initiation of metamorphosis, and completion of metamorphosis) as well as effects on survival, metabolic rate, size at metamorphosis, and duration and loss of weight during metamorphosis. Most elements were accumulated in a dose-dependent pattern by some or all life stages, although this was not the case for Hg. For most elements, larval body burdens exceeded those of later life stages in some or all treatments (control, low, or high). However for Se, As, and Hg, body burdens in control and low concentrations were increased in later compared with earlier life stages. A lack of dose-dependent accumulation of Hg suggests that the presence of high concentrations of other elements (possibly Se) either inhibited accumulation or increased depuration of Hg. The duration of metamorphosis (forelimb emergence through tail resorption) was lengthened in individuals exposed to the highest concentrations of elements, but there were no other statistically significant biological effects. This study shows that patterns of accumulation and possibly depuration of metals and trace elements are complex in animals possessing complex life cycles. Further study is required to determine specific interactions affecting these patterns, in particular which elements may be responsible for affecting accumulation or retention of Hg when organisms are exposed to complex mixtures of elements.