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BACKGROUND: Several approaches have been proposed for ultrasound-guided thoracic paravertebral block, but the best approach remains unclear. OBJECTIVE: We compared two ultrasound-guided in-plane approaches using a microconvex probe, transverse and parasagittal. We assessed whether either approach would facilitate successful catheter placement in the paravertebral space. DESIGN: Randomised controlled trial. SETTING: University hospital, July 2015 to March 2016. PATIENTS: Sixty patients scheduled to undergo thoracotomy were randomly allocated into two groups. INTERVENTIONS: A microconvex probe was placed transversely between adjacent ribs (transverse) or sagittally between adjacent transverse processes (parasagittal). When the Tuohy needle reached the paravertebral space, a catheter was inserted to a depth of 4âcm. Then, 0.5-ml radiocontrast was injected through the catheter under fluoroscopy. MAIN OUTCOME MEASURES: The primary outcome was successful catheter placement in the paravertebral space; secondary outcomes were 0 to 100âmm visual analogue scale pain score and morphine consumption in the first 24âh. RESULTS: All patients received the allocated paravertebral block. Correct catheter placement occurred in 23 (77%) and 24 patients (80%) using the transverse (n=30) and parasagittal approaches (n=30), respectively (Pâ=â1.00). Five patients were excluded due to changes in surgical procedure. Postoperative pain, represented by median [IQR] visual analogue scale score, was 19.5 [12 to 25] at rest and 55 [44 to 77] on movement with the transverse approach (n=28) vs. 22 [12 to 33.5] at rest and 59 [41.5 to 75] on movement with the parasagittal approach (n=27) (Pâ=â0.57 at rest, Pâ=â0.76 on movement). Median morphine consumption was 11.5 [5 to 21] and 11 [5 to 18]âmg in the transverse and parasagittal approaches, respectively (Pâ=â0.99). CONCLUSION: There were no clinically significant differences between approaches for continuous ultrasound-guided thoracic paravertebral block using a microconvex probe, and both approaches achieved a high rate of correct catheter placement. TRIAL REGISTRATION: UMIN Clinical Trials Registry identifier: UMIN000015988.
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Bloqueo Nervioso , Ultrasonografía Intervencional , Catéteres , Humanos , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control , UltrasonografíaRESUMEN
PURPOSE: Thoracic paravertebral block (TPVB) provides a unilateral nerve block at multiple intercostal levels allowing injection of a local anesthetic into paravertebral space (PVS) via a needle or catheter. However, the most effective injection method remains unclear. This study compared the real-time spread of ropivacaine between two paravertebral injection methods using thoracoscopy. METHODS: Thirty-four patients scheduled for thoracoscopic surgery were randomly allocated into the Needle or Catheter groups, and performed transverse in-plane ultrasound-guided TPVB. The Needle group received 20 ml of 0.5% ropivacaine via a needle placed into the lateral edge of PVS; the Catheter group received the same dose of ropivacaine via a catheter inserted 5 cm into PVS. The primary outcome was the spreading pattern of ropivacaine in each group. The secondary outcome was intraoperative vasopressor requirement after paravertebral injection. RESULTS: In the Needle group, all cases showed ropivacaine spread to multiple intercostal levels, mainly across the ribs. Contrastingly, the Catheter group showed variable spreading patterns; multiple intercostal levels (n = 10) [across the ribs (n = 4), anterolateral aspect of the vertebral bodies (n = 6)] or unobservable spreading (no change; n = 7) (P = 0.007). Vasopressors were required in two and ten cases in the Needle and Catheter groups, respectively (P = 0.010). CONCLUSION: Paravertebral injection via a needle typically resulted in spreading to multiple intercostal levels, especially across the ribs on the peripheral side of injection site, whereas injection via a catheter resulted in variable spreading patterns. Therefore, injections via needles are more stable.
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Agujas , Bloqueo Nervioso , Anestésicos Locales , Catéteres , Humanos , Dolor Postoperatorio , Columna Vertebral , Ultrasonografía IntervencionalRESUMEN
PURPOSE: Previous work showed that 20 mL of local anesthetic (LA) did not spread into the paravertebral space (PVS) via the intramuscular quadratus lumborum block (QLBi). If spread of LA into the PVS can be achieved by increasing the total LA volume, QLBi can be more effective. We hypothesized that a larger volume of LA for the QLBi would spread into the PVS. METHODS: This crossover volunteer study included five healthy men. For comparison, both the ultrasound-guided QLB type 2 (QLB2) and QLBi were employed on opposite sides of each volunteer, and the spread of LA solution (0.7 mL/kg) mixed with contrast media in the PVS was assessed 1 h after the first injection using magnetic resonance imaging. Sensory loss was evaluated by pinprick 90 min post-injection. Each volunteer underwent both QLB types, and the same procedures were administered on opposite sides 7 days after the first experiment. RESULTS: In total, 20 QLB blocks (10 QLB2 and 10 QLBi) were performed. LA did not spread into the PVS after the QLBi. The sensory block area included the lower abdomen after the QLB2, but not after the QLBi. The sensory block area did not extend to the upper abdominal region or the midline of the lower abdomen with either block method. CONCLUSION: LA administered by the QLB2 spreads into the PVS of T10-T12, resulting in lower and lateral abdominal sensory loss. In contrast, LA administered by the QLBi does not spread into the PVS and results in only lateral abdominal sensory loss.
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Anestésicos Locales/administración & dosificación , Bloqueo Nervioso/métodos , Adulto , Estudios Cruzados , Humanos , Inyecciones , Imagen por Resonancia Magnética , Masculino , Ultrasonografía Intervencional , Adulto JovenRESUMEN
Organic contaminants, in particular persistent organic pollutants (POPs), adversely affect water quality and aquatic food webs across the globe. As of now, there is no globally consistent information available on concentrations of dissolved POPs in water bodies. The advance of passive sampling techniques has made it possible to establish a global monitoring program for these compounds in the waters of the world, which we call the Aquatic Global Passive Sampling (AQUA-GAPS) network. A recent expert meeting discussed the background, motivations, and strategic approaches of AQUA-GAPS, and its implementation as a network of networks for monitoring organic contaminants (e.g., POPs and others contaminants of concern). Initially, AQUA-GAPS will demonstrate its operating principle via two proof-of-concept studies focused on the detection of legacy and emerging POPs in freshwater and coastal marine sites using both polyethylene and silicone passive samplers. AQUA-GAPS is set up as a decentralized network, which is open to other participants from around the world to participate in deployments and to initiate new studies. In particular, participants are sought to initiate deployments and studies investigating the presence of legacy and emerging POPs in Africa, Central, and South America.
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Monitoreo del Ambiente , Contaminantes Químicos del Agua , Agua Dulce , Humanos , Agua , Calidad del AguaRESUMEN
Diphenylarsinic acid (DPAA) is an organic arsenic compound used for the synthesis of chemical weapons. We previously found that the residents of Kamisu city in Ibaraki Prefecture, Japan, were exposed to DPAA through contaminated well water in 2003. Although mounting evidence strongly suggests that their neurological symptoms were caused by DPAA, the dynamics of DPAA distribution and metabolism after ingestion by humans remain to be elucidated. To accurately predict the distribution of DPAA in the human body, we administrated DPAA (1.0 mg/kg/day) to cynomolgus monkeys (n = 28) for 28 days. The whole tissues from these monkeys were collected at 5, 29, 170, and 339 days after the last administration. The concentration of DPAA in these tissues was measured by liquid chromatography-mass spectrometry. We found that DPAA accumulated in the central nervous system tissues for a longer period than in other tissues. This finding would extend our knowledge on the distribution dynamics and metabolism of DPAA in primates, including humans. Furthermore, it may be useful for developing a treatment strategy for patients who are exposed to DPAA.
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Arsenicales/farmacocinética , Sistema Nervioso Central/metabolismo , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Animales , Arsenicales/administración & dosificación , Femenino , Macaca fascicularis , Masculino , Modelos Animales , Factores de Tiempo , Distribución TisularRESUMEN
PURPOSE: We conducted a comparative study to evaluate analgesic efficacy between paravertebral block via the surgical field (PVB-sf), in which the catheter was inserted into the ventral side of the sympathetic trunk in the paravertebral space by a thoracic surgeon under thoracoscopic visualization, and epidural block (Epi) using ropivacaine for post-thoracotomy pain relief. METHODS: Lung cancer patients scheduled for lobectomy via thoracotomy were randomly allocated to receive either PVB-sf or Epi (n = 36 per group). Before thoracotomy closure, 0.375% ropivacaine was administered as a bolus (PVB-sf, 20 mL; Epi, 5 mL), followed by a 300-mL continuous infusion of 0.2% ropivacaine at 5 mL/h. Postoperative pain was assessed using a visual analog scale (VAS) score at various time points, including the primary endpoint of 2 h after ropivacaine bolus injection. Sensory block area, vital signs, serum ropivacaine concentrations, and side effects were also evaluated. RESULTS: The Epi group showed significantly lower VAS scores and blood pressure and a wider sensory block area than the PVB-sf group at all evaluation time points. While the mean serum ropivacaine concentration in the PVB-sf group was significantly higher than that in the Epi group until 1 h after injection of the ropivacaine bolus, there was no significant difference at any subsequent assessment point. The incidence of side effects was similar between the groups. CONCLUSION: The Epi was superior to PVB-sf for the management of post-thoracotomy pain in this patient cohort. The number of dermatomes anaesthetized by Epi was greater than that anaesthetized by PVB-sf. No difference in complication rates was observed between the two groups.
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Amidas/administración & dosificación , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Toracotomía/métodos , Anciano , Analgésicos/uso terapéutico , Anestesia Epidural/efectos adversos , Anestesia Epidural/métodos , Anestesia Local/efectos adversos , Anestesia Local/métodos , Anestésicos Locales/administración & dosificación , Presión Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/efectos adversos , Dimensión del Dolor , Estudios Prospectivos , RopivacaínaRESUMEN
Patients undergoing abdominal surgery can experi- ence severe pain due to the abdominal wall incision. Epidural anesthesia has been considered as the gold standard for perioperative analgesia in abdominal sur- gery. However, currently, many patients receive pro- phylactic anticoagulation therapy preoperatively with potential complications. For such cases, while epidural anesthesia is contraindicated, the use of ultrasound- guided peripheral nerve block is increasing. In abdomi- nal surgery, ultrasound-guided rectus sheath block and transversus abdominis plane block are commonly used for perioperative analgesia. The use of ultrasound ren- ders these block techniques safe and reliable. Cur- rently, a new abdominal peripheral nerve block, qua- dratus lumborum block, is gaining attention because it is thought to have a wider range of analgesia and a longer duration of effect As the analgesic properties of these blocks are limited in extent and duration, it is important to select the appropriate approach. Ultrasound-guided abdominal trunk block can con- tribute to perioperative multimodal analgesia.
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Abdomen/cirugía , Bloqueo Nervioso , Humanos , Manejo del Dolor , Dolor Postoperatorio/etiología , UltrasonografíaRESUMEN
Breakage of an epidural catheter occurs rarely dur- ing the insertion or removal procedures. In previous reports, the broken epidural catheter fragment need not be removed in asymptomatic patients. However, late-onset neurological symptoms might occur. This is a case of delayed onset subdural hematoma due to a broken epidural catheter retained in the body for 18 years. We considered that the catheter fragment might induce chronic inflammation and vascular fragil- ity around the catheter. Antiplatelet therapy might lead to the hematoma because this patient took an aspirin (antiplatelet drug) for over 9 years. Antiplatelet and anticoagulant therapies are likely to be a risk of hematoma. Thus, even without neurological symptoms, it is necessary to consider the removal of the epidural catheter fragment in patients on anti- platelet and anticoagulant therapy.
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Anestesia Epidural/efectos adversos , Hematoma Subdural Agudo/etiología , Anticoagulantes/uso terapéutico , Aspirina/uso terapéutico , Femenino , Hematoma Subdural Agudo/diagnóstico por imagen , Hematoma Subdural Agudo/cirugía , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéuticoRESUMEN
Aerosol samples were collected from Tsukuba, Japan, soon after the 2011 Fukushima nuclear accident and analyzed for speciation of radiocesium and radioiodine to explore their chemical behavior and isotopic ratios after the release. Most (134)Cs and (137)Cs were bound in organic matter (5391%) and some in water-soluble fractions (515%), whereas a negligible proportion of radiocesium remained in minerals. This pattern suggests that sulfate salts and organic matter may be the main carrier of Cs-bearing particles. The (129)I in aerosol samples is contained in various proportions as soluble inorganic iodine (I() and IO3()), soluble organic iodine, and unextractable iodine. The measured mean (129)I/(131)I atomic ratio of 16.0 ± 2.2 is in good agreement with that measured from rainwater and consistent with ratios measured in surface soil samples. Together with other aerosols and seawater samples, an initial (129)I/(137)Cs activity ratio of â¼4 × 10(7) was obtained. In contrast to the effectively constant (134)Cs/(137)Cs activity ratios (1.04 ± 0.04) and (129)I/(131)I atomic ratios (16.0 ± 2.2), the (129)I/(137)Cs activity ratios scattered from 3.5 × 10(7) to 5 × 10(6) and showed temporally and spatially different dispersion and deposition patterns between radiocesium and radioiodine. These findings confirm that (129)I, instead of (137)Cs, should be considered as a proxy for (131)I reconstruction.
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Contaminantes Radiactivos del Aire/análisis , Radioisótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Radioisótopos de Yodo/análisis , Monitoreo de Radiación/métodos , Contaminantes Radiactivos del Suelo/análisis , Aerosoles , JapónRESUMEN
We measured the natural abundances of radiocarbon (delta14C) in macroinvertebrates, fishes, and their potential food sources, collected from the upper and lower reaches of six temperate streams in Lake Biwa basin (central Japan), three of which flow on limestone bedrock. Several carbon storage reservoirs in the watersheds show distinctive delta14C signatures (e.g., ancient carbonate rocks, -1000 per thousand; modern atmospheric CO2, +50 per thousand). Our analyses showed that the delta14C values for periphytic algae range from -361 per thousand to +21 per thousand, reflecting 14C-depleted signals from watershed storage reservoirs (carbonate rocks and/or soils). In contrast, the delta14C values for coarse particulate organic matter (CPOM) range from -6 per thousand to +62 per thousand, reflecting 14C-enriched signals from modern atmospheric CO2. The periphyton from streams on limestone bedrock was more 14C-depleted than that from streams in non-limestone areas, although the delta14C values for periphyton from the latter were less than modern atmospheric 14CO2 concentration. The delta14C values for most of the consumers were between those for periphyton and CPOM. Based on a delta14C two-source mixing models, the results suggested that the grazers rely on periphyton, while the carbon source for collectors and predators shifts from CPOM in the upper reaches of streams to periphyton in the lower reaches. The delta14C signature can trace carbon from watershed storage reservoirs to benthic production, which suggests that stream food webs are composed of mixtures of carbon originating from various sources of different ages.
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Carbono/metabolismo , Peces/fisiología , Cadena Alimentaria , Invertebrados/fisiología , Ríos , Animales , Carbono/química , Isótopos de Carbono/química , Japón , LagosRESUMEN
The present study aimed to clarify whether dose-response profiles of acute behavioral effects of 1,2-dichloroethane (DCE), 1,1,1-trichloroethane (TCE), trichloroethylene (TRIC), and tetrachloroethylene (PERC) differ. A test battery involving 6 behavioral endpoints was applied to evaluate the effects of DCE, TCE, TRIC, and PERC in male ICR strain mice under the same experimental conditions. The behavioral effect dose-response profiles of these compounds differed. Regression analysis was used to evaluate the relationship between the dose-response profiles and structural and physical properties of the compounds. Dose-response profile differences correlated significantly with differences in specific structural and physical properties. These results suggest that differences in specific structural and physical properties of DCE, TCE, TRIC, and PERC are responsible for differences in behavioral effects that lead to a variety of dose-response profiles.
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Conducta Animal/efectos de los fármacos , Hidrocarburos Clorados/toxicidad , Animales , Condicionamiento Operante/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Dicloruros de Etileno/toxicidad , Conducta Alimentaria/efectos de los fármacos , Hidrocarburos Clorados/química , Masculino , Ratones , Ratones Endogámicos ICR , Estructura Molecular , Actividad Motora/efectos de los fármacos , Esquema de Refuerzo , Relación Estructura-Actividad , Tetracloroetileno/toxicidad , Tricloroetanos/toxicidad , Tricloroetileno/toxicidadRESUMEN
BACKGROUND: There is global concern over significant threats from a wide variety of environmental hazards to which children face. Large-scale and long-term birth cohort studies are needed for better environmental management based on sound science. The primary objective of the Japan Environment and Children's Study (JECS), a nation-wide birth cohort study that started its recruitment in January 2011, is to elucidate environmental factors that affect children's health and development. METHODS/DESIGN: Approximately 100,000 expecting mothers who live in designated study areas will be recruited over a 3-year period from January 2011. Participating children will be followed until they reach 13 years of age. Exposure to environmental factors will be assessed by chemical analyses of bio-specimens (blood, cord blood, urine, breast milk, and hair), household environment measurements, and computational simulations using monitoring data (e.g. ambient air quality monitoring) as well as questionnaires. JECS' priority outcomes include reproduction/pregnancy complications, congenital anomalies, neuropsychiatric disorders, immune system disorders, and metabolic/endocrine system disorders. Genetic factors, socioeconomic status, and lifestyle factors will also be examined as covariates and potential confounders. To maximize representativeness, we adopted provider-mediated community-based recruitment. DISCUSSION: Through JECS, chemical substances to which children are exposed during the fetal stage or early childhood will be identified. The JECS results will be translated to better risk assessment and management to provide healthy environment for next generations.
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Ambiente , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/efectos adversos , Adolescente , Adulto , Biomarcadores/sangre , Biomarcadores/metabolismo , Biomarcadores/orina , Niño , Protección a la Infancia , Preescolar , Estudios de Cohortes , Simulación por Computador , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/metabolismo , Composición Familiar , Femenino , Sangre Fetal/química , Cabello/química , Humanos , Lactante , Recién Nacido , Japón , Estudios Longitudinales , Masculino , Exposición Materna/efectos adversos , Leche Humana/química , Embarazo , Complicaciones del Embarazo/inducido químicamente , Proyectos de InvestigaciónRESUMEN
OBJECTIVE: There are no reports from Japan showing the effects of using the thromboelastography algorithm on transfusion requirements after Intensive Care Unit (ICU) admission, and post-implementation knowledge regarding the thromboelastography algorithm under the Japanese healthcare system is insufficient. Therefore, this study aimed to clarify the effect of the TEG6s thromboelastography algorithm on transfusion requirements for patients in the ICU after cardiac surgery. METHODS: We retrospectively compared the requirements for blood transfusion up to 24 h after ICU admission using the thromboelastography algorithm (January 2021 to April 2022) (thromboelastography group; n = 201) and specialist consultation with surgeons and anesthesiologists (January 2018 to December 2020) (non-thromboelastography group; n = 494). RESULTS: There were no significant between-group differences in terms of age, height, weight, body mass index, operative procedure, duration of surgery or cardiopulmonary bypass, body temperature, or urine volume during surgical intervention. Moreover, there was no significant between-group difference in the amount of drainage at 24 h after ICU admission. However, crystalloid and urine volumes were significantly higher in the thromboelastography group than in the non-thromboelastography group. Additionally, fresh-frozen plasma (FFP) transfusion volumes were significantly lower in the thromboelastography group. However, there were no significant between-group differences in red blood cell count or platelet transfusion volume. After variable adjustment, the amount of FFP used from the operating room to 24 h after ICU admission was significantly reduced in the thromboelastography group. CONCLUSIONS: The thromboelastography algorithm optimized transfusion requirements at 24 h after admission to the ICU following cardiac surgery.
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Procedimientos Quirúrgicos Cardíacos , Tromboelastografía , Humanos , Tromboelastografía/métodos , Estudios Retrospectivos , Transfusión Sanguínea/métodos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/métodos , Unidades de Cuidados Intensivos , ProbabilidadRESUMEN
Prey subsidies originating from detritus add nutrients and energy to arboreal communities. Measurement of this subsidy is required in the understanding of how food web dynamics respond to changes in surrounding environments. Shrub spiders are one of the key predators involved in food web coupling. We evaluate the effects of potential changes in prey availabilities during secondary succession on the contribution of subsidy from detrital food webs to shrub spiders and how different spider feeding guilds used the subsidy of prey from detrital food webs. We measured the relative importance of the subsidy for the spider feeding guilds, using the ratios of stable isotopes of C (δ(13)C), and N (δ(15)N) and C isotope discrimination (Δ(14)C). Diet age was calculated from Δ(14)C values, because old diet ages of spiders indicate that the spiders consume prey from detrital food sources. Dominant aerial prey (Diptera) had a distinctively old diet age compared with arboreal prey, which indicates that aerial prey were subsidized from detrital food webs. Sit-and-wait spiders tended to have an older diet age than active hunting spiders, which indicates that sit-and-wait spiders depended more on subsidies. Diet age varied only slightly for spiders in stands of different ages, indicating that rates at which spiders use grazing and detrital prey are probably determined more by foraging strategies and not by stand age. A dominance of sit-and-wait predators will lead to higher detrital subsidy inputs in shrub habitats. This study highlights the effect of shrub spider community structure (feeding guild composition) on the volume of the subsidy received from the detrital food web.
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Biota , Dieta , Conducta Alimentaria/fisiología , Cadena Alimentaria , Suelo/análisis , Arañas/fisiología , Factores de Edad , Análisis de Varianza , Animales , Isótopos de Carbono/análisis , Radioisótopos de Carbono/análisis , Insectos/anatomía & histología , Insectos/química , Japón , Espectrometría de Masas , Isótopos de Nitrógeno/análisis , Hojas de la Planta/químicaRESUMEN
The chemical pollution crisis severely threatens human and environmental health globally. To tackle this challenge the establishment of an overarching international science-policy body has recently been suggested. We strongly support this initiative based on the awareness that humanity has already likely left the safe operating space within planetary boundaries for novel entities including chemical pollution. Immediate action is essential and needs to be informed by sound scientific knowledge and data compiled and critically evaluated by an overarching science-policy interface body. Major challenges for such a body are (i) to foster global knowledge production on exposure, impacts and governance going beyond data-rich regions (e.g., Europe and North America), (ii) to cover the entirety of hazardous chemicals, mixtures and wastes, (iii) to follow a one-health perspective considering the risks posed by chemicals and waste on ecosystem and human health, and (iv) to strive for solution-oriented assessments based on systems thinking. Based on multiple evidence on urgent action on a global scale, we call scientists and practitioners to mobilize their scientific networks and to intensify science-policy interaction with national governments to support the negotiations on the establishment of an intergovernmental body based on scientific knowledge explaining the anticipated benefit for human and environmental health.
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The radiocarbon ((14)C) of total carbon (TC) in atmospheric fine particles was measured at 6 h or 12 h intervals at two sites, 50 and 100 km downwind from Tokyo, Japan (Kisai and Maebashi) in summer 2007. The percent modern carbon (pMC) showed clear diurnal variations with minimums in the daytime. The mean pMC values at Maebashi were 28 ± 7 in the daytime and 45 ± 16 at night (37 ± 15 for the overall period). Those at Kisai were 26 ± 9 in the daytime and 44 ± 8 at night (37 ± 12 for the overall period). This data indicates that fossil sources were major contributors to the daytime TC, while fossil and modern sources had comparable contributions to nighttime TC in the suburban areas. At both sites, the concentration of fossil carbon as well as O(3) and the estimated secondary organic carbon increased in the daytime. These results suggest that fossil sources around Tokyo contributed significantly to the high daytime concentration of secondary organic aerosols (SOA) at the two suburban sites. A comparison of pMC and the ratio of elemental carbon/TC from our particulate samples with those from three end-member sources corroborates the dominant role of fossil SOA in the daytime.
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Movimientos del Aire , Ritmo Circadiano , Material Particulado/análisis , Estaciones del Año , Carbono/análisis , Radioisótopos de Carbono , Fósiles , Compuestos Orgánicos/análisis , Ozono/análisis , TokioRESUMEN
Diphenylarsinic acid (DPAA), an artificial phenyl arsenic compound, is considered a groundwater pollutant in Japan. Previous human and animal studies suggested that DPAA affects the central nervous system; however, these effects are poorly understood. The present study investigated the toxicokinetic characteristics and effects of DPAA on dopamine (DA) in the striatum of free-moving mice after a single oral administration. In a simultaneous blood and brain microdialysis study, only DPAA was detectable in both blood and striatum dialysate samples immediately after DPAA administration. DPAA concentrations in the striatum and blood dialysate rapidly reached a maximum, then decreased over time in an essentially parallel manner. A more detailed brain microdialysis examination of intracerebral kinetics revealed that the concentration of DPAA in the striatum dialysate began to increase within 15 min, reaching a maximum approximately 1 h after administration, and then decreased with a biological half-life of approximately 2 h. Moreover, a single oral administration of DPAA at 0.5-32 mg/kg affected the extracellular DA level in the striatum. The effect on DA level changed slowly after DPAA administration, with a bell-shaped dose-response relationship. The present study suggests that DPAA is rapidly absorbed into the blood circulating in the gastrointestinal tract and passes through the blood-brain barrier to subsequently affect DA levels in the striatum in mice after a single oral administration.
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Arsenicales/efectos adversos , Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Administración Oral , Animales , Arsenicales/administración & dosificación , Arsenicales/sangre , Arsenicales/farmacocinética , Barrera Hematoencefálica/metabolismo , Cuerpo Estriado/metabolismo , Neuronas Dopaminérgicas/metabolismo , Relación Dosis-Respuesta a Droga , Masculino , Ratones Endogámicos ICR , Microdiálisis , Permeabilidad , ToxicocinéticaRESUMEN
Radionuclides produced by 20th-century human nuclear activities from 1945 (e.g., atmospheric nuclear explosions and nuclear-fuel reprocessing) made significant impacts on earth's surface environments. Long-lived shallow-water corals living in tropical/subtropical seas incorporate the anthropogenically-produced radionuclides, including 129I and 14C, into their skeletons, and provide time series records of the impacts of nuclear activities. Here, we present 129I/127I and Δ14C time series records of an annually-banded modern coral skeleton from Rowley Shoals, off the northwestern coast of Australia, in the far eastern Indian Ocean. The 129I/127I and Δ14C records, covering the period 1930s-1990s, exhibit distinct increases caused by the nuclear activities, and their increasing profiles are clearly different from each other. The first distinct 129I/127I increase occurs from 1955 to 1959, followed by a decrease in 1960-1963. The increase is probably due to US atmospheric nuclear explosions in Bikini and Eniwetok Atolls in 1954, 1956 and 1958. The 129I produced in those nuclear tests would be transported by the North Equatorial Current, a portion of which passes through the Indonesian Throughflow and then reaches Rowley Shoals. This initial increase from 1955 is, however, absent in the Δ14C record, which shows a distinct increase from 1959 and its peak around the mid-1970s, followed by a gradual decrease. This absence and the 4-year-delayed Δ14C increase are likely due to dilution of explosion-produced 14C with natural carbon (by seawater mixing and air-sea gas exchange) being much more intense than that of explosion-produced 129I with natural iodine (by the same processes), suggesting that the 129I/127I ratio is a more conservative anthropogenic tracer in surface ocean waters, as compared to Δ14C. The second 129I/127I increase is contemporaneous with a rapid Δ14C increase during 1964-1967, followed by a rapid 129I/127I decrease in 1968-1969; the increases can be ascribed to very large atmospheric nuclear explosions conducted in the former Soviet Union in 1961-1962. The third 129I/127I increase appears between 1969/1970 and 1992, which can be attributed to airborne 129I released from nuclear-fuel reprocessing facilities in Europe, the former Soviet Union and the US. The coral 129I/127I and Δ14C time series records, combined with previous studies, enhance our understanding of the behavior of anthropogenic 129I and 14C in the global ocean and atmosphere.
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Antozoos , Monitoreo de Radiación , Animales , Atmósfera , Australia , Europa (Continente) , Humanos , Océano Índico , Indonesia , Radioisótopos de Yodo , Agua de Mar , U.R.S.S.RESUMEN
Eutrophication and hypoxia are major problems affecting the health of coastal ecosystems throughout the world. Tokyo Bay, Japan, is a eutrophic coastal area where the abundance of the megabenthic community has been decreasing. To assess factors associated with the impaired biota, seasonal surveys of the megabenthic community and water and sediment quality were conducted in the bay. Cluster analysis showed a difference in the community structure between the northern and southern parts of the bay. The density of species and species diversity were high throughout the year in the southern part of the bay, whereas in the northern part of the bay species diversity was low and defaunation occurred in August. At this time, bottom hypoxia due to temperature and salinity stratification, and high concentrations of nutrients, chlorophyll a, and organic matter in the water column and/or sediment, dominated the northern part of the bay. In October, bottom hypoxia was less severe but was still present in the northern part of the bay, and recolonization by mobile fishes and sessile mussels occurred. Multivariate analyses of the megabenthic community and environmental parameters in August showed the spatial pattern of the community could be explained by concentrations of dissolved oxygen and particulate organic carbon in the bottom water, and total sulfide and total organic carbon in the sediments. In particular, impairment of the biota in the northern area could be explained by the threshold concentrations of dissolved oxygen < 1.7 mL L(-1) and total organic carbon > 20.3 mg g(-1).
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Biodiversidad , Eutrofización , Agua de Mar/química , Contaminantes del Agua/análisis , Animales , Biomasa , Carbono/análisis , Clorofila/análisis , Clorofila A , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos/química , Densidad de Población , Estaciones del Año , TokioRESUMEN
As ultrasound beam does not penetrate the air, it has long been thought that ultrasound imaging is not useful for evaluation of the pulmonary parenchyma. However, recent studies have shown that the artifact pattern generated by the lung can be used for the diagnosis of acute respiratory failure. Lung ultrasonography can provide us important informations inside the lung in a real-time fashion. Furthermore, general application of extended ultrasonography would be of greater benefit for perioperative diagnosis and intervention.