RESUMO
Eight contaminants were used to perform a surrogate contamination test to evaluate safety of the process for producing recycled pulp for adult paper diapers. We performed a safety evaluation of the recycling process for producing recycled pulp following the European Food Safety Authority safety assessment for polyethylene terephthalate (PET) bottles using recycled PET. We also compared the first tier safety limit established on the basis of TTC (Climit) in the pulp that contained recycled pulp with residual contaminant concentrations (Cres). If Climit > Cres, there is no concern regarding safety of the recycling process. Climit was determined to be 0.46 mg/kg-pulp based on the human exposure threshold of 0.15 µg/person/day using the scenario in which a bedridden senior citizen uses four adult paper diapers manufactured with pulp containing 10% recycled pulp per day. Cres was derived from the initial concentration in used pulp (0.17 mg/kg-pulp), and decontamination rate was obtained from the surrogate contamination test. The Cres of the eight contaminants were between 0.0017 and 0.10 mg/kg-pulp, which were all below the Climit of 0.46 mg/kg-pulp. These results indicated there was no safety problem regarding this process for producing recycled pulp for adult paper diapers.
Assuntos
Fraldas para Adultos/normas , Polietilenotereftalatos/análise , Polietilenotereftalatos/normas , Reciclagem/normas , Humanos , Reciclagem/métodos , Estados Unidos , United States Food and Drug Administration/normasRESUMO
To determine the amounts and chemical forms of chlorine compounds in elemental chlorine-free (ECF) bleached pulp for sanitary products, a chemical-form-based quantitative analysis flow scheme was created. The scheme involves quantitative determination of compounds eluted in elution tests assuming dermal exposure. The results indicated that most of the chlorine compounds in pulp used for sanitary products were insoluble organically bound chlorine and water-soluble chlorides consisting of chloride ions. The total amount of chlorine obtained by analysis of the total chlorine in the pulp products was close to the sum of the amounts of water-soluble chlorides, residual chlorine, chloroacetic acids, and insoluble organically bound chlorine. Therefore, the balance of chlorine measured by the flow scheme was acceptable. Little residual chlorine was detected in the pulp products, suggesting that the chlorine dioxide used for bleaching was almost completely converted into inactive inorganic chlorides and organic chlorine compounds and that these substances do not affect the health risk posed by pulp products. A risk assessment of the detected chloroacetic acid and dichloroacetic acid revealed that there is no concern about the health risk posed by use of these products.
Assuntos
Compostos Clorados/efeitos adversos , Compostos Clorados/química , Cloro/efeitos adversos , Cloro/química , Óxidos/efeitos adversos , Água/químicaRESUMO
We developed a lead substances selection approach based on the concept of mixture classification of UN GHS for the purpose of efficient risk assessment of mixtures consisting of multiple components. Lead substances selection methods are being actively developed in Europe, but these methods are predicated on the regulations and information sources available within Europe and are therefore not readily applicable to countries outside Europe. In this study, the features of the GHS-based approach and the risk assessment results for outdoor painting work as a specific utilization example of the GHS-based approach were described. Comparison with the DPD + method and the CCA method proposed in Europe revealed that the GHS-based approach resulted in the selection of the safest lead substances. The GHS method, like the DPD + method, is a classification-based approach. We believe that a classification-based approach based on the GHS method can be an appropriate tool to efficiently implement risk assessment of mixtures for countries outside Europe. Some tools for business operators to conduct the management of chemicals using the GHS classification have been established in Japan. We plan to propose the GHS-based approach as a standardized assessment tool.
Assuntos
Misturas Complexas/toxicidade , Substâncias Perigosas/toxicidade , Pintura/toxicidade , Local de Trabalho , Misturas Complexas/química , Europa (Continente) , Substâncias Perigosas/química , Humanos , Internacionalidade , Japão , Legislação de Medicamentos , Medição de RiscoRESUMO
A risk assessment study of seven phthalates in paper diapers for newborn babies produced in Japan was performed. The diapers were purchased and the contents of the seven phthalates were determined and estimated amounts of exposure were calculated based on the eluted rate into artificial medium of urine or sweat, average weight of infants, and frequency of use. Di-2-ethylhexyl phthalate and di-n-butyl phthalate were detected in the topsheets and determined to be 0.6 µg/g and 0.2 µg/g, respectively. The daily estimated exposure volume was calculated to be in the range of 1.86 × 10(-10)-2.98 × 10(-6) mg/kg/day as follows: content of seven phthalates in the topsheet (0.1-1 µg/g) × eluted rate of phthalates into artificial sweat (0.0006-2.4%) × weight of the topsheet of a diaper (1.5 g) × the number of diapers used per day (12 sheets) × skin absorption rate (0.005-0.1)/average body weight (2.9 kg). For hazard assessment, we used 0.2-300 mg/kg/day for the seven phthalates based on the data available at international agencies. The margin of exposure to the seven phthalates was 6.71 × 10(4)-1.99 × 10(11), indicating that the risk of exposure to phthalates from the diapers produced in Japan was negligible.
Assuntos
Fraldas Infantis/efeitos adversos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Ácidos Ftálicos/efeitos adversos , Ácidos Ftálicos/química , Pele/metabolismo , Peso Corporal/efeitos dos fármacos , Certificação/métodos , Dietilexilftalato/efeitos adversos , Dietilexilftalato/química , Poluentes Ambientais/efeitos adversos , Poluentes Ambientais/análise , Humanos , Lactente , Japão , Papel , Medição de Risco , SegurançaRESUMO
A risk assessment study of dioxins in sanitary napkins produced in Japan was performed. The daily estimated exposure volume to dioxins was compared with the tolerable daily intake (TDI). The concentrations of dioxins such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) in seven sanitary napkins were measured using gas chromatography and mass spectroscopy analytical methods. Among the seven napkins, a range of 0.0044-0.076pg TEQ/g dioxins was measured. Daily estimated exposure volume from sanitary napkins was calculated as follows: (dioxin volumes in a sanitary napkin (0.0044-0.076pg TEQ/g)×pulp weight in a sanitary napkin (11.2g)×used napkin numbers/d (7.5)×the number of days/month that women use sanitary napkins (7)×skin absorption rate (0.03)×used years (40))/(average body weight of women (50kg)×the number of days in the month (30)×life years (86)). Daily exposure volumes were estimated to be 0.000024-0.00042pg TEQ/kg/d. For hazard assessment, we used 0.7pg TEQ/kg/d which was the lowest level of TDI among TDI values reported by international agencies. When the daily exposure volume was compared with the TDI, the former was approximately 1666-29,166 times less than the latter. This fact indicated that the risk of exposure to dioxins from sanitary napkins produced in Japan was negligible.
Assuntos
Benzofuranos/análise , Produtos de Higiene Menstrual/normas , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzofuranos Policlorados , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Japão , Nível de Efeito Adverso não Observado , Dibenzodioxinas Policloradas/análise , Medição de Risco/métodosRESUMO
Chromatin accessibility is a hallmark of active regulatory regions and is functionally linked to transcriptional networks and cell identity. However, the molecular mechanisms and networks that govern chromatin accessibility have not been thoroughly studied. Here we conducted a genome-wide CRISPR screening combined with an optimized ATAC-see protocol to identify genes that modulate global chromatin accessibility. In addition to known chromatin regulators like CREBBP and EP400, we discovered a number of previously unrecognized proteins that modulate chromatin accessibility, including TFDP1, HNRNPU, EIF3D and THAP11 belonging to diverse biological pathways. ATAC-seq analysis upon their knockouts revealed their distinct and specific effects on chromatin accessibility. Remarkably, we found that TFDP1, a transcription factor, modulates global chromatin accessibility through transcriptional regulation of canonical histones. In addition, our findings highlight the manipulation of chromatin accessibility as an approach to enhance various cell engineering applications, including genome editing and induced pluripotent stem cell reprogramming.
Assuntos
Cromatina , Sequenciamento de Nucleotídeos em Larga Escala , Cromatina/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Histonas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Redes Reguladoras de GenesRESUMO
Ornithine transcarbamylase (OTC) plays a significant role in the urea cycle, a metabolic pathway functioning in the liver to detoxify ammonia. OTC deficiency (OTCD) is the most prevalent urea cycle disorder. Here, we show that intravenously delivered human OTC (hOTC) mRNA by lipid nanoparticles (LNP) was an effective treatment for OTCD by restoring the urea cycle. We observed a homotrimer conformation of hOTC proteins produced by the mRNA-LNP in cells by cryo-electron microscopy. The immunohistochemistry revealed the mitochondria localization of produced hOTC proteins in hepatocytes in mice. In livers of mice intravenously injected with hOTC-mRNA/LNP at 1.0 mg/kg, the delivered hOTC mRNA levels steeply decreased with a half-life (t1/2) of 7.1 h, whereas the produced hOTC protein levels retained for 5 days and then declined with a t1/2 of 2.2 days. In OTCD model mice (high-protein diet-fed Otcspf-ash hemizygous males), a single dose of hOTC-mRNA/LNP at 3.0 mg/kg ameliorated hyperammonemia and weight loss with prolonged survival rate (22 days) compared with that of untreated mice (11 days). Weekly repeated doses at 0.3 and 1.0 mg/kg were well tolerated in wild-type mice and showed a dose-dependent amelioration of survival rate in OTCD mice, thus, showing the therapeutic potential of LNP-formulated hOTC mRNA for OTCD.
RESUMO
Blastocyst complementation is an intriguing way of generating humanized animals for organ preparation in regenerative medicine and establishing novel models for drug development. Confirming that complemented organs and cells work normally in chimeric animals is critical to demonstrating the feasibility of blastocyst complementation. Here, we generated thymus-complemented chimeric mice, assessed the efficacy of anti-PD-L1 antibody in tumor-bearing chimeric mice, and then investigated T-cell function. Thymus-complemented chimeric mice were generated by injecting C57BL/6 (B6) embryonic stem cells into Foxn1nu/nu morulae or blastocysts. Flow cytometry data showed that the chimeric mouse thymic epithelial cells (TECs) were derived from the B6 cells. T cells appeared outside the thymi. Single-cell RNA-sequencing analysis revealed that the TEC gene-expression profile was comparable to that in B6 mice. Splenic T cells of chimeric mice responded very well to anti-CD3 stimulation in vitro; CD4+ and CD8+ T cells proliferated and produced IFNγ, IL-2, and granzyme B, as in B6 mice. Anti-PD-L1 antibody treatment inhibited MC38 tumor growth in chimeric mice. Moreover, in the chimeras, anti-PD-L1 antibody restored T-cell activation by significantly decreasing PD-1 expression on T cells and increasing IFNγ-producing T cells in the draining lymph nodes and tumors. T cells produced by complemented thymi thus functioned normally in vitro and in vivo. To successfully generate humanized animals by blastocyst complementation, both verification of the function and gene expression profiling of complemented organs/cells in interspecific chimeras will be important in the near future.
Assuntos
Blastocisto , Linfócitos T CD8-Positivos , Animais , Blastocisto/metabolismo , Quimera/genética , Células-Tronco Embrionárias , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Of the 354 substances designated as class I under the Pollutant Release and Transfer Register (PRTR) law in Japan, we reviewed the sensitization data of the selected 144 substances and analyzed it from various aspects comparing human and animal data, determining the relationship between skin sensitization and chemical structure and comparing the various international organizations. Although most of them were expected to be hazardous substances, 49 out of the 144 substances lacked both human and animal sensitization data. Positive substances accounted for 69% and 42% of the substances for which sensitization data were available in the case of humans and animals, respectively. A correlation was observed between the chemical structures of the substances and sensitization, despite the relatively few substances examined in this study and the limited homogeneity of the collected data. In particular, epoxides clearly had sensitizing potentials and more than half of carboxylic esters or dicarboxyl anhydrides, aliphatic aldehydes, and aromatic compounds with at least two hydroxyl groups also had sensitizing potentials. Also, this study clearly demonstrated the lack of consistency across the sensitization assessment criteria adopted by different countries or among those adopted by the same country on the basis of different laws or administrative measures.
Assuntos
Alérgenos/toxicidade , Poluentes Ambientais/toxicidade , Substâncias Perigosas/toxicidade , Testes Cutâneos/normas , Alérgenos/química , Alérgenos/classificação , Animais , Poluentes Ambientais/química , Poluentes Ambientais/classificação , Saúde Global , Substâncias Perigosas/classificação , Humanos , Agências Internacionais/normas , Japão , Sistema de Registros , Pele/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Insulin degludec (IDeg) is a new insulin formulation that facilitates long-term control of glucose level in humans. In this study, we investigated the effects of IDeg on glycemic control in dogs. Its time-action profiles were monitored in healthy dogs using an artificial pancreas apparatus under euglycemic conditions. At 9.0-13.5 hr post-IDeg injection, an indistinct peak of glucose level was detected. Moreover, the action of IDeg was persistent for >20 hr. Both IDeg and neutral protamine Hagedorn insulin (NPH) lowered blood glucose concentrations in diabetic dogs, but IDeg caused postprandial hyperglycemia and a somewhat lower preprandial glucose level than that caused by NPH. IDeg might be ineffective in concurrently preventing postprandial hyperglycemia and preprandial hypoglycemia in a single-agent administration.
Assuntos
Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/veterinária , Doenças do Cão/tratamento farmacológico , Insulina de Ação Prolongada/uso terapêutico , Animais , Glicemia , Cães , Relação Dose-Resposta a Droga , Insulina Isófana/administração & dosagem , Insulina Isófana/uso terapêutico , Insulina de Ação Prolongada/administração & dosagemRESUMO
We report a case of subcutaneous Pseudallescheria boydii/Scedosporium apiospermum complex infection occurring in a 77-year-old Japanese female farmer suffering from interstitial pneumonia. Seven months prior to the current presentation, she noticed nodes on her right forearm after pulling up weeds, and the nodes grew larger. Two soft dome-shaped, protruded nodes ( 15 mm and 30 mm in size ) had fused together on the extensor surface of the right forearm. Yellowish-white, rice-grain-sized pustules clustered on the surface. Histopathological examination of the skin specimen showed large and small abscesses surrounded by epithelioid granuloma; separate branching hyphae within the granulation tissue were stained with PAS. No grains were observed. Fungal culture yielded fast-growing, grayish-white, fluffy colonies which were identified as Scedosporium apiospermum (Clade 4) using sequence analysis of the ß-tubulin gene. We also reviewed 28 previously reported Japanese cases of P. boydii or S. apiospermum infection presenting with skin manifestations.
Assuntos
Dermatomicoses/microbiologia , Dermatomicoses/patologia , Pseudallescheria/isolamento & purificação , Scedosporium/isolamento & purificação , Administração Oral , Idoso , Povo Asiático , Ciclosporina/administração & dosagem , Ciclosporina/efeitos adversos , Dermatomicoses/diagnóstico , Dermatomicoses/etiologia , Feminino , Humanos , Pneumonias Intersticiais Idiopáticas/complicações , Pneumonias Intersticiais Idiopáticas/tratamento farmacológico , Hospedeiro Imunocomprometido , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversosRESUMO
The purpose of this study was to investigate the correlations in skin and eye irritations between rabbits and humans using published international databases. We selected 60 and 56 compounds for skin and eye irritation, respectively. When the reactions were divided into irritation-negative or irritation-positive, including corrosion, similar reactions between rabbits and humans were detected for 53 compounds in skin irritation and 54 compounds in eye irritation, showing rates of agreement in skin and eye as 88% and 96%, respectively. These findings revealed that correlation in skin and eye irritations between rabbits and humans were high. However, corrosion was observed in rabbit skin treated with 14 compounds, 4 of which showed similar changes in humans, and in rabbit eyes treated with 9 compounds, 1 of which revealed similar changes in humans. These findings indicated that the incidence of corrosion was higher in rabbits than in humans. Our results showed that the data on rabbit irritations in the skin and eye were useful for identifying risk of irritation in human.
Assuntos
Olho/efeitos dos fármacos , Irritantes/toxicidade , Pele/efeitos dos fármacos , Animais , Humanos , CoelhosRESUMO
The purpose of this study was to investigate the endocrine-mediated effects of the benzene-related compounds with reference to Organization for Economic Co-operation and Development (OECD) Test Guideline No. 407. Rats were orally gavaged with 0, 10, 50, and 250 mg/kg/day of 1-chloro-4-(chloromethyl)benzene, and 0, 25, 150, and 1000 mg/kg/day of 1,3-diethyl benzene for at least 28 days, beginning at 8 weeks of age. Thyroid dysfunction was observed in rats given the 1,3-diethyl benzene. Serum T4 values increased in all groups of male rats and in the 1000 mg/kg group of female rats, and TSH values also increased in the 1000 mg/kg groups of both sexes after 28 days' administration. Decreased T3 values were observed in the 1000 mg/kg group of female rats after 28 days' administration, and hormone values increased in the 1000 mg/kg groups of both sexes after the 14-day recovery period. In addition, thyroid weight increased in the 1000 mg/kg groups and thyroid follicular cell hyperplasia was detected in one male rat from the 1000 mg/kg group after 28 days' administration. Endocrine-mediated effects, including thyroid dysfunction were not observed in any groups of rats treated with 1-chloro-4-(chloromethyl)benzene. Our results indicated that endocrine-mediated effects such as thyroid dysfunction were associated with some benzene-related compounds.
Assuntos
Derivados de Benzeno/toxicidade , Clorobenzenos/toxicidade , Glândula Tireoide/efeitos dos fármacos , Administração Oral , Animais , Derivados de Benzeno/administração & dosagem , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Hormônios Tireóideos/sangue , Testes de Toxicidade SubagudaRESUMO
A 65-year-old man presenting with visceral malperfusion complicating acute type A aortic dissection underwent emergent surgery. Bypass grafting from the right common iliac artery to the superior mesenteric artery was performed prior to central aortic repair because intestinal ischemia caused hemodynamic instability. Subsequently, the ascending aorta was replaced with a Dacron graft under a condition of circulatory arrest with selective cerebral perfusion. Endotoxin adsorption was carried out intraoperatively in parallel with cardiopulmonary bypass to prevent postoperative end-organ failure. The patient recovered uneventfully and was discharged from our hospital 31 days after surgery.
Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Endotoxinas/sangue , Hemoperfusão/métodos , Intestino Delgado/irrigação sanguínea , Isquemia/terapia , Oclusão Vascular Mesentérica/terapia , Doença Aguda , Idoso , Dissecção Aórtica/sangue , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Aneurisma Aórtico/sangue , Aneurisma Aórtico/complicações , Aneurisma Aórtico/diagnóstico por imagem , Ponte Cardiopulmonar , Humanos , Cuidados Intraoperatórios , Isquemia/diagnóstico por imagem , Isquemia/etiologia , Masculino , Oclusão Vascular Mesentérica/sangue , Oclusão Vascular Mesentérica/diagnóstico por imagem , Oclusão Vascular Mesentérica/etiologia , Polimixina B/uso terapêutico , Tomografia Computadorizada por Raios X , Resultado do TratamentoAssuntos
Pustulose Exantematosa Aguda Generalizada/etiologia , Anti-Inflamatórios/efeitos adversos , Prednisolona/efeitos adversos , Pustulose Exantematosa Aguda Generalizada/patologia , Anti-Inflamatórios/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Prednisolona/administração & dosagem , Pele/patologiaRESUMO
An 82-year-old man with a mycotic aortic aneurysm of the distal arch underwent urgent surgery because of sepsis. The infected aortic arch was excised, replaced with a rifampicin-bonded prosthetic graft, and covered with omentum. Direct hemoperfusion using polymyxin B-immobilized fiber (PMX-DHP) was intraoperatively carried out in parallel with the cardiopulmonary circuit. Intraoperative PMX-DHP dramatically reduced the level of plasma endotoxin, and ameliorated hemodynamic instability and oxygenation, resulting in smooth weaning from cardiopulmonary bypass. Intraoperative endotoxin adsorption is technically simple and easy, effective in hemodynamic stabilization, and so could be a new therapeutic option for mycotic aortic aneurysm.