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Traditional technologies for virtual reality (VR) and augmented reality (AR) create human experiences through visual and auditory stimuli that replicate sensations associated with the physical world. The most widespread VR and AR systems use head-mounted displays, accelerometers and loudspeakers as the basis for three-dimensional, computer-generated environments that can exist in isolation or as overlays on actual scenery. In comparison to the eyes and the ears, the skin is a relatively underexplored sensory interface for VR and AR technology that could, nevertheless, greatly enhance experiences at a qualitative level, with direct relevance in areas such as communications, entertainment and medicine1,2. Here we present a wireless, battery-free platform of electronic systems and haptic (that is, touch-based) interfaces capable of softly laminating onto the curved surfaces of the skin to communicate information via spatio-temporally programmable patterns of localized mechanical vibrations. We describe the materials, device structures, power delivery strategies and communication schemes that serve as the foundations for such platforms. The resulting technology creates many opportunities for use where the skin provides an electronically programmable communication and sensory input channel to the body, as demonstrated through applications in social media and personal engagement, prosthetic control and feedback, and gaming and entertainment.
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Realidade Aumentada , Desenho de Equipamento , Pele , Tato , Interface Usuário-Computador , Realidade Virtual , Tecnologia sem Fio/instrumentação , Comunicação , Epiderme , Retroalimentação , Feminino , Humanos , Masculino , Próteses e Implantes , Robótica , Mídias Sociais , Vibração , Jogos de VídeoRESUMO
BACKGROUND: To predict whether the left pulmonary artery (LPA) to the main pulmonary artery (MPA) ratio measured by echocardiography in left congenital diaphragmatic hernia (CDH) was related to death or need for extracorporeal membrane oxygenation (ECMO). METHODS: This retrospective study analyzed neonates with left CDH born between 2018 and 2022 in a single tertiary medical institution. Echocardiography was performed immediately after birth. The diameter of the LPA was measured at the bifurcation, and the diameter of the MPA was measured at the maximal dimension during the systolic phase. The Nakata index, McGoon ratio, and ejection fraction (EF) were analyzed and compared with the LPA: MPA ratio as predictive values. RESULTS: Seventy-two neonates with left CDH were included, 19 (26.4%) died or needed ECMO, and 53 (73.6%) survived without ECMO. The lower observed/expected lung-to-head ratio, lower EF, lower LPA: MPA ratio, lower RPA: MPA ratio, lower Nakata index, and lower McGoon ratio were associated with death or need for ECMO. By multivariate analysis, lower LPA: MPA ratio, RPA: MPA ratio, and Nakata index were independent postnatal risk factors for death or need for ECMO. Among the measurements, the LPA: MPA ratio had the highest area under the curve (0.957) with a sensitivity of 84.2% and specificity of 96.3% at a cut-off value of 31.2%. CONCLUSION: In patients with left CDH, the LPA: MPA ratio measured by echocardiography could be used as an independent postnatal predictor of death or need for ECMO.
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Hérnias Diafragmáticas Congênitas , Recém-Nascido , Humanos , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/terapia , Artéria Pulmonar/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos , EcocardiografiaRESUMO
BACKGROUND: Right-sided congenital diaphragmatic hernia (RCDH) is relatively rare compared with left-sided congenital diaphragmatic hernia (LCDH). Clinical data of RCDH, especially with respect to antenatal prediction of neonatal outcome, are lacking. The aim of this study was to report the treatment outcomes of patients with antenatally diagnosed RCDH and to evaluate the predictability of observed-to-expected lung area-to-head circumference ratio (O/E LHR) for perinatal outcomes, focused on mortality or extracorporeal membrane oxygenation (ECMO) requirement. METHODS: We retrospectively reviewed the medical records of newborn infants with isolated RCDH. We analyzed and compared the clinical and prenatal characteristics including the fetal lung volume, which was measured as the O/E LHR, between the survivors and the non-survivors. RESULTS: A total of 26 (66.7%) of 39 patients with isolated RCDH survived to discharge. The O/E LHR was significantly greater in survivors (64.7 ± 21.2) than in non-survivors (40.5 ± 23.4) (P =.027). It was greater in survivors without ECMO requirement (68.3 ± 15.1) than non-survivors or those with ECMO requirement (46.3 ± 19.4; P = .010). The best O/E LHR cut-off value for predicting mortality in isolated RCDH was 50. CONCLUSIONS: The findings in this study suggest that O/E LHR, a well-characterized prognostic indicator in LCDH, could be applied to a fetus with antenatally diagnosed RCDH. A large cohort study is required to verify the association between O/E LHR values and the graded severity of RCDH.
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Hérnias Diafragmáticas Congênitas , Feminino , Idade Gestacional , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/terapia , Humanos , Lactente , Recém-Nascido , Pulmão/diagnóstico por imagem , Gravidez , Prognóstico , Estudos Retrospectivos , Ultrassonografia Pré-NatalRESUMO
Patent ductus arteriosus (PDA) is the most common congenital cardiovascular disorder in dogs and requires an accurate diagnosis for an appropriate treatment. Cardiac MRI (cMRI) has been reported as a method for characterization of canine thoracic vasculature. However, to the authors' knowledge, no published studies describe evaluation of canine PDA through cMRI. Three dogs were selected for this exploratory study. Electrocardiogram gating and breath-hold techniques were performed using a 3T MR scanner. Both black blood imaging and bright blood cine acquisitions were performed. Quantification of stroke volume (SV) and shunting volume were calculated using a stack of short-axis cine images. Additional 4D (three-spatial dimensions plus time)-TRAK (time-resolved MR angiography with keyhole) sequences were conducted in patient 2 to verify other vasculature abnormality. Black blood images clearly depicted the course of the ductus from the descending aorta to the pulmonary artery in all three dogs. Morphological evaluation of PDA classified patients 1 and 2 as Type 2a and patient 3 as Type 1. Patient 2 was confirmed to have a concurrent persistent left cranial vena cava. Left ventricular SV, right ventricular SV, and left-to-right SV ratio were 12.4 ml, 3.36 ml, and 3.704, respectively, in patient 1; 6.85 ml, 1.22 ml, and 5.60 in the patient 2; and 3.67 ml, 2.14 ml, and 1.702 in patient 3. Findings indicated that cMRI is a feasible method for characterizing the morphology of PDA and extracardiac vasculature anomalies in dogs.
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Aorta Torácica/diagnóstico por imagem , Doenças do Cão/diagnóstico por imagem , Permeabilidade do Canal Arterial/veterinária , Artéria Pulmonar/diagnóstico por imagem , Animais , Aorta Torácica/patologia , Doenças do Cão/patologia , Cães , Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/patologia , Feminino , Imageamento por Ressonância Magnética/veterinária , Masculino , Artéria Pulmonar/patologiaRESUMO
The present study investigated the effect of object representation on attentional priority regarding distractor inhibition and target search processes while the statistical regularities of singleton distractor location were biased. A color singleton distractor appeared more frequently at one of six stimulus locations, called the 'high-probability location,' to induce location-based suppression. Critically, three objects were presented, each of which paired two adjacent stimuli in a target display by adding background contours (Experiment 1) or using perceptual grouping (Experiments 2 and 3). The results revealed that attention capture by singleton distractors was hardly modulated by objects. In contrast, target selection was impeded at the location in the object containing the high-probability location compared to an equidistant location in a different object. This object-based suppression in target selection was evident when object-related features were parts of task-relevant features. These findings suggest that task-irrelevant objects modulate attentional suppression. Moreover, different features are engaged in determining attentional priority for distractor inhibition and target search processes.
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The resurgence of influenza viruses as a significant global threat emphasizes the urgent need for innovative antiviral strategies beyond existing treatments. Here, we present the development and evaluation of a novel super-multivalent sialyllactosylated filamentous phage, termed t-6SLPhage, as a potent entry blocker for influenza A viruses. Structural variations in sialyllactosyl ligands, including linkage type, valency, net charge, and spacer length, were systematically explored to identify optimal binding characteristics against target hemagglutinins and influenza viruses. The selected SLPhage equipped with optimal ligands, exhibited exceptional inhibitory potency in in vitro infection inhibition assays. Furthermore, in vivo studies demonstrated its efficacy as both a preventive and therapeutic intervention, even when administered post-exposure at 2 days post-infection, under 4 lethal dose 50% conditions. Remarkably, co-administration with oseltamivir revealed a synergistic effect, suggesting potential combination therapies to enhance efficacy and mitigate resistance. Our findings highlight the efficacy and safety of sialylated filamentous bacteriophages as promising influenza inhibitors. Moreover, the versatility of M13 phages for surface modifications offers avenues for further engineering to enhance therapeutic and preventive performance.
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Bronchopulmonary dysplasia (BPD) is a serious chronic lung disease affecting extremely preterm infants. While mitochondrial dysfunction has been investigated in various medical conditions, limited research has explored mitochondrial DNA (mtDNA) gene mutations, specifically in BPD. This study aimed to evaluate mitochondrial mtDNA gene mutations in extremely preterm infants with BPD. In this prospective observational study, we enrolled a cohort of extremely preterm infants diagnosed with BPD. Clinical data were collected to provide comprehensive patient profiles. Peripheral blood mononuclear cells were isolated from whole-blood samples obtained within a defined timeframe. Subsequently, mtDNA extraction and sequencing using next-generation sequencing technology were performed to identify mtDNA gene mutations. Among the cohort of ten extremely preterm infants with BPD, mtDNA sequencing revealed the presence of mutations in seven patients, resulting in a total of twenty-one point mutations. Notably, many of these mutations were identified in loci associated with critical components of the respiratory chain complexes, vital for proper mitochondrial function and cellular energy production. This pilot study provides evidence of mtDNA point mutations in a subset of extremely preterm infants with BPD. These findings suggest a potential association between mitochondrial dysfunction and the pathogenesis of BPD. Further extensive investigations are warranted to unravel the mechanisms underlying mtDNA mutations in BPD.
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Displasia Broncopulmonar , Doenças Mitocondriais , Lactente , Humanos , Recém-Nascido , Lactente Extremamente Prematuro , Displasia Broncopulmonar/genética , Leucócitos Mononucleares , Projetos Piloto , Mutação , DNA Mitocondrial/genéticaRESUMO
INTRODUCTION: This study aimed to investigate the outcomes of infants at 18-24 months born in the Korean Neonatal Network with a birth weight <500 g. METHODS: The anthropometric and neurodevelopmental data of infants with a birth weight <500 g at a gestational age of ≥22 weeks who were registered in the Korean Neonatal Network 2013-2017 and followed up at a corrected age of 18-24 months were reviewed. Neurodevelopmental impairment was defined as the presence of any of the following: (1) cerebral palsy; (2) severe visual impairment; (3) hearing impairment; or (4) cognitive impairment. Cognitive impairment was defined as (1) a Bayley Scales of Infant Development-II Mental Development Index score <70; and (2) Bayley Scales of Infant and Toddler Development-III Cognitive and Language Composite scores <85. Cognitive testing was performed for infants with suspected problems upon clinician's referral to developmental specialists. RESULTS: At a median corrected age of 20 months, 26/52 (50%) of included infants had neurodevelopmental impairment. Cerebral palsy, severe visual impairment, wearing of glasses, hearing impairment, and cognitive impairment occurred in 22%, 0%, 8%, 5%, and 57% of the included infants, respectively. The proportions of infants with <2 standard deviations of weight, length, and head circumference were 54%, 52%, and 56%, respectively. The majority (70%) of infants were rehospitalized, and the most common cause was respiratory problems. CONCLUSION: Half of infants with a birth weight <500 g in Korea may exhibit neurodevelopmental impairment and growth retardation at a corrected age of 18-24 months. Multidisciplinary follow-up along with continuous rehabilitation will be needed to improve neurological and physical development in this special population.
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Paralisia Cerebral , Perda Auditiva , Recém-Nascido , Lactente , Feminino , Humanos , Pré-Escolar , Criança , Peso ao Nascer , Estudos de Coortes , Paralisia Cerebral/diagnóstico , Paralisia Cerebral/epidemiologia , Paralisia Cerebral/etiologia , Perda Auditiva/epidemiologia , Perda Auditiva/complicações , Transtornos da Visão/epidemiologia , República da Coreia/epidemiologia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Deficiências do Desenvolvimento/etiologiaRESUMO
BACKGROUND: Right-sided congenital diaphragmatic hernia (RCDH) is a rare and often fatal congenital anomaly, primarily attributed to lung hypoplasia, which is associated with small branch pulmonary artery (PA). This study investigated whether postnatal PA measurements obtained through echocardiography are associated with mortality or the extracorporeal membrane oxygenation (ECMO) requirement in neonates with RCDH. METHODS: A retrospective study was conducted on neonates with RCDH born between 2008 and 2022. Echocardiography was performed on the day of birth. The diameter of the main PA (MPA) was measured at the maximal dimension, and the diameters of the left PA (LPA) and right PA (RPA) were measured at the bifurcation. The primary outcome was mortality or ECMO requirement. Parameters, including the LPA:MPA ratio, RPA:MPA ratio, Nakata index, McGoon ratio, and ejection fraction (EF), were analyzed and compared with the observed-to-expected lung-to-head ratio (o/e LHR), initial blood gas, and defect size as predictive values. RESULTS: Among 39 neonates with RCDH, 25 (64.1 %) survived without ECMO. The non-survivor or ECMO group exhibited lower o/e LHR, reduced EF, smaller LPA and RPA diameters, and larger MPA diameter than survivors. Lower LPA:MPA ratio, Nakata index, McGoon ratio, and higher initial PaCO2 were associated with adverse outcomes. Notably, the LPA:MPA ratio showed the highest predictive capability (area under the curve, 0.983; p < 0.001). CONCLUSION: The LPA:MPA ratio is a promising postnatal predictor of mortality or ECMO requirement in neonates with RCDH. Additionally, Nakata index, McGoon ratio, and initial PaCO2 are significantly correlated with outcomes. LEVEL OF EVIDENCE: This is a level III. TYPE OF STUDY: Prognostic study.
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Ecocardiografia , Oxigenação por Membrana Extracorpórea , Hérnias Diafragmáticas Congênitas , Artéria Pulmonar , Humanos , Hérnias Diafragmáticas Congênitas/mortalidade , Hérnias Diafragmáticas Congênitas/terapia , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Estudos Retrospectivos , Recém-Nascido , Artéria Pulmonar/diagnóstico por imagem , Feminino , Masculino , PrognósticoRESUMO
Introduction: MIRAGE syndrome is a rare disease characterized by myelodysplasia, infection, growth restriction, adrenal hypoplasia, genital phenotypes, and enteropathy. Herein, we report the case of a girl with MIRAGE syndrome who presented with adrenal insufficiency and chronic diarrhea. Case presentation: The patient was born at 29 + 6 weeks of gestational age with a birth weight of 656 g (<3p). Her height and head circumference were also <3p. At birth, she presented with respiratory distress, meconium staining, and pneumomediastinum, which were managed with high-frequency ventilation and empirical antibiotics. Physical examination showed generalized hyperpigmentation and normal female genitalia. A few days after birth, polyuria and hypotension developed, and laboratory findings revealed hypoglycemia, hyponatremia, and hyperkalemia. Plasma adrenocorticotropic hormone levels were elevated with low serum cortisol levels and high plasma renin activity, which were suggestive of adrenal insufficiency. Hydrocortisone and fludrocortisone were introduced and maintained, and hyperpigmentation attenuated with time. Both kidneys looked dysplastic, and adrenal glands could not be traced on abdominal ultrasound. From the early days of life, thrombocytopenia and anemia were detected, but not to life-threatening level and slowly recovered up to the normal range. Despite aggressive nutritional support, weight gain and growth spurt were severely retarded during the hospital stay. Additionally, after introducing enteral feeding, she experienced severe diarrhea and subsequent perineal skin rashes and ulcerations. Fecal calprotectin level was highly elevated; however, a small bowel biopsy resulted in non-specific submucosal congestion. The patient was diagnosed with MIRAGE syndrome with SAMD9 gene mutation. She was discharged with tube feeding and elemental formula feeding continued, but chronic diarrhea persisted. By the time of the last follow-up at 15 months of corrected age, she was fortunately not subjected to severe invasive infection and myelodysplastic syndrome. However, she was dependent on tube feeding and demonstrated a severe developmental delay equivalent to approximately 5-6 months of age. Conclusion: The early diagnosis of adrenal crisis and hormone replacement therapy can save the life of -patients with MIRAGE syndrome; however, chronic intractable diarrhea and growth and developmental delay continue to impede the patient's well-being.
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Insuficiência Adrenal , Hiperpigmentação , Síndromes Mielodisplásicas , Humanos , Recém-Nascido , Lactente , Feminino , Retardo do Crescimento Fetal/genética , Peptídeos e Proteínas de Sinalização Intracelular , Insuficiência Adrenal/complicações , Insuficiência Adrenal/diagnóstico , Insuficiência Adrenal/genética , Recém-Nascido Prematuro , Diarreia/genética , Síndromes Mielodisplásicas/genéticaRESUMO
Societal concerns about air quality in East Asia are still growing despite country-level efforts to reduce air pollution emissions. In coping with this growing concern, the government and the public demand a longerlead forecast of air quality to ensure sufficient response time until society prepares for countermeasures such as a temporary reduction of specific emission sources. Here we propose a novel method that produces skillful seasonal forecasting of wintertime (December to February) PM10 concentration over South Korea. The method is based on the idea that climate condition and air quality have co-variability in the seasonal time scales and that the state-of-art seasonal prediction model will benefit air quality forecasting. More specifically, a linear regression model is constructed to link observed winter PM10 concentration and climate variables where the predicted climate variables were furnished from NCEP CFSv2 forecast initialized during autumn. In this case, climate variables were selected as predictors of the model because they are not only physically related to air quality but also 'predictable' in CFS hindcast. Through analysis of retrospective forecasts of 20 winters for the period 2001-2020, we found this model shows statistically significant skill for the seasonal forecast of wintertime PM10 concentration.
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Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Estudos Retrospectivos , Estações do AnoRESUMO
In this study, we present the case of a 900 g, male infant born at 27+5 weeks, who was placed on high frequency oscillatory ventilation (HFOV) until repair of a left congenital diaphragmatic hernia (CDH) at 39 days of life (DOL). To date, this is the smallest infant with repair of the left CDH reported in the literature. After birth, he passed the cardiopulmonary stabilization phase and successfully underwent delayed surgery; in the process, he received ventilator assistance through HFOV. He weighed 1,660 gm at the time of surgery. We performed the thoracoscopic primary closure of the diaphragmatic defect. He was extubated on post-operation day (POD) 7 and discharged from hospital on POD 36 with 0.1 L/min supplemental oxygen via nasal cannula. He is being followed for growth and development and there has been no recurrence at the surgical site at 24 months of corrected age. In this case, high mean airway pressure (MAP) was required based on the patient's weight to achieve adequate recruitment of the left lung, and the patient was diagnosed with mental developmental delay on Bayley Scales of Infant Development-II. Thus, we suggest that the postnatal course and long-term outcomes for extremely low birth weight (ELBW) and preterm infants with left CDH is different from that for full-term babies. Therefore, future research should focus on preterm infants with left CDH.
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In this study, a simplified method for the extraction and determination of seven fluoroquinolone residues (danofloxacin, difloxacin, enrofloxacin, marbofloxacin, orbifloxacin, ofloxacin, and sarafloxacin) and three quinolones (oxolinic acid, flumequine, and nalidixic acid), in porcine muscle, table eggs, and commercial whole milk, which required no cleanup step, was devised. This procedure involves the extraction of analytes from the samples via liquid-phase extraction, and the subsequent quantitative determination was accomplished via LC-fluorescence detection. Analyte separation was successfully conducted on an XBridge-C(18) column, with a linear gradient mobile phase composed of acetonitrile and 0.01 M oxalic acid buffer at pH=3.5. The one-step liquid-liquid extraction method evidenced good selectivity, precision (RSDs=0.26-15.07%), and recovery of the extractable analytes, ranging from 61.12 to 115.93% in matrices. The LOQs ranged from 0.3 to 25 microg/kg. A survey of ten samples purchased from local markets was conducted, and none of the samples harbored fluoroquinolone residues. This method is an improvement over existing methodologies, since no additional cleanup was necessary.
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Resíduos de Drogas/análise , Ovos/análise , Leite/química , Músculo Esquelético/química , Quinolonas/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Medições Luminescentes , Reprodutibilidade dos Testes , SuínosRESUMO
To ensure public safety against veterinary drug residues in food products from animal sources, maximum residue limits (MRLs) should be established by scientific evidence and a transparent estimation process. The Joint Food and Agriculture Organization (FAO)/World Health Organization (WHO) Expert Committee on Food Additives (JECFA) developed an Excel workbook-based tool for MRLs evaluation in 2003. In this study, we developed a web-based tool for MRL evaluation, called Korean MRL evaluation tools (KMET). While KMET used algorithms of JECFA workbook, it added some databases (e.g., Korean food consumption database) and provided additional functions (e.g., selection of target marker residue). Web-based KMET enabled regulatory policy makers to update the database. All input data and output results related to MRL evaluation based on residue depletion and food consumption datasets were archived and provided overall processes from the initial depletion data entry to MRL establishment with user-friendly interface. Our results demonstrated the stepwise processes whereby MRL for trichlorfon in the muscle of Paralichthys olivaceus was established with functional descriptions of KMET. MRL for trichlorfon derived from KMET was proposed and notified by the Ministry of Food and Drug Safety in 2018.
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Resíduos de Drogas/análise , Política Ambiental/legislação & jurisprudência , Triclorfon/análise , Drogas Veterinárias/análise , Agricultura , Animais , Resíduos de Drogas/normas , Pesqueiros/estatística & dados numéricos , Alimentos , Aditivos Alimentares , Contaminação de Alimentos/legislação & jurisprudência , Contaminação de Alimentos/estatística & dados numéricos , Abastecimento de Alimentos , Humanos , Internet , Resíduos de Praguicidas , República da Coreia , Triclorfon/normas , Drogas Veterinárias/normas , Organização Mundial da SaúdeRESUMO
To measure the levels of dioxin-like compounds, pork, mackerel, cheese and milk were analyzed. The food samples were obtained at three different markets in Seoul. All the samples were animal origin and their lipid contents ranged from 4% to 34%. After extraction, extracts were cleaned up by sulfuric acid impregnated silica gel, purified on a series of silica gel, alumina, carbon column chromatography and then analyzed by high resolution gas chromatography/high resolution mass spectrometry. The levels of polychlorinated dibenzo-p-dioxins/furans for pork, mackerel, cheese and milk were 0.0008, 0.8663, 0.002 and 0.0236 pgTEQ/g wet weight, respectively. In addition, the levels of non-ortho coplanar polychlorinated biphenyls for pork, mackerel, cheese and milk were 0.0041, 1.5781, 0.0259 and 0.0353 pgTEQ/g wet weight, respectively. Among food samples analyzed, pork showed the lowest level of dioxin-like compounds.
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Benzofuranos/análise , Laticínios , Contaminação de Alimentos , Carne , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análise , Poluentes do Solo/análise , Animais , Dibenzofuranos Policlorados , Monitoramento Ambiental , Humanos , Coreia (Geográfico) , Saúde PúblicaRESUMO
Recently, reproductive and neurobehavioral effects of bisphenol A (BPA) have been documented, and thus a review was requested for BPA management direction by the government. Therefore, this study was performed to establish a Korean tolerable daily intake (TDI) for BPA. An expert committee, consisting of specialists in fields such as toxicology, medicine, pharmacology, and statistics, was asked to evaluate BPA health based guidance values (HbGVs) . Although many toxicological studies were reviewed to select a point of departure (POD) for TDI, rat and mouse reproductive studies by Tyl et al. (2002, 2006) , which were performed according to GLP standards and OECD guidelines, were selected. This POD was the lowest value determined from the most sensitive toxicological test. The POD, a NOAEL of 5 mg/kg bw/day, was selected based on its systemic toxicity as critical effects. An uncertainty factor of 100 including interspecies and intraspecies differences was applied to calculate the TDI. According to the evaluation results, a TDI of BPA for Korean was suggested at 0.05 mg/kg bw/day. In addition, the BPA exposure level based on food consumption by the Korean population was estimated as 1.509 µg/kg bw/day, and the HI was evaluated at 0.03 when the TDI of 0.05 mg/kg bw/day was applied. This HI value of 0.03 indicated that hazardous effects would not be expected from BPA oral exposures. Although highly uncertain, further studies on low dose neurobehavioral effects of BPA should be performed. In addition, it is recommended that the 'as low as reasonably achievable' (ALARA) principle be applied for BPA exposure from food packaging materials in newborn infants and children.
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The primary objective of this study was to develop a simple, rapid, and efficient method for the simultaneous determination of four fluoroquinolone residues, ciprofloxacin (CFX), danofloxacin (DFX), enrofloxacin (EFX) and norfloxacin (NFX), in chicken eggs. The samples were first monitored by microbiological assay using Escherichia coli as the reference organism, and were then quantified using HPLC with a fluorescence detector. Egg samples were extracted by the liquid-phase extraction process, and the analytes were analyzed via an ODS column using a mixture of acetonitrile and 0.4% phosphoric acid-0.4% triethylamine (15: 85, v/v) as a mobile phase (pH=2) without purification. The calibration curves were linear (r2>or=0.999) over a concentration range of 0.1-1.0 microg/mL. The majority of the mean recoveries at four different fortification levels, 0.1, 0.2, 0.5 and 1.0 ppm, ranged from 73.7+/-7.2% to 87.1+/-12.7%, and the repeatability (as the relative standard deviation) from three repetitive determinations of recovery was between 1.03 and 18.83%. The calculated limit of quantitation (LOQ) was 9 ppb for CFX, EFX and NFX and 0.6 ppb for DFX. Both the bioassay and HPLC methods were applied to 120 total egg samples collected from the six major cities in the Republic of Korea. The bioassay, showed that two samples were positive (i.e contained inhibiting substances). On the other hand, the results of HPLC only identified and quantified the residues of enrofloxacin (from 0.43 to 1.02 ppm) in three samples out of 120. We concluded that the bioassay can be used as a routine screening method for the presence of fluoroquinolones in chicken eggs, which can be confirmed and quantified using LC.