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This paper presents a point-cloud mapping method using a light detection and ranging (LiDAR) mounted on a helmet worn by a rider of micro-mobility. The distortion in LiDAR measurements, which is caused by motion and shaking of micro-mobility and rider, is corrected by estimating the pose (3D positions and attitude angles) of the helmet based on the information from normal distributions transform-based simultaneous localization and mapping (NDT SLAM) and an inertial measurement unit. A Kalman filter-based algorithm for the distortion correction is presented under the assumption that the helmet moves at nearly constant translational and angular velocities in any directions. The distortion-corrected LiDAR measurements are mapped onto an elevation map, and the measurements relating to stationary objects in the environments are extracted using the occupancy grid method. The stationary object measurements are utilized to build a point-cloud map. The experimental results in a campus road environment demonstrate the effectiveness of the proposed method.
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OBJECTIVES: We investigated the effect of daily folic acid supplementation on methotrexate (MTX) toxicity and efficacy in Japanese patients with rheumatoid arthritis (RA). METHODS: We followed 19 patients treated with MTX who switched from taking weekly 5 mg folic acid supplementation (weekly regimen) to 1.25 mg daily (daily regimen). White blood cell (WBC) and platelet (PLT) counts, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels were collected for 24 weeks following the change. RESULTS: We observed no significant changes in WBC or PLT counts. AST and ALT levels, which had exceeded the upper limits of their normal ranges at the beginning of the study, were improved significantly at weeks 4 and 8, no subsequent deterioration in liver function was found. Further, no significant changes in ESR and CRP levels were observed. CONCLUSION: Our data indicate that supplementing 1.25 mg of folic acid daily rather than 5 mg weekly reduces toxicity caused by MTX without affecting its efficacy.
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Artrite Reumatoide , Monitoramento de Medicamentos/métodos , Ácido Fólico , Hematínicos , Metotrexato , Idoso , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Hematínicos/administração & dosagem , Hematínicos/sangue , Humanos , Japão/epidemiologia , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Resultado do TratamentoRESUMO
OBJECTIVES: To elucidate the impact of regulation of tricuspid regurgitation (TR) using tricuspid annuloplasty on postoperative changes in right ventricular (RV) systolic and diastolic functions. METHODS: We enrolled 69 patients who underwent aortic or mitral valve surgery between July 2016 to March 2018 without recurrence. Patients with concomitant coronary artery bypass grafting or a history of previous cardiovascular surgery were excluded, remaining 45 patients enrolled. Patients were divided into two groups according to concomitant tricuspid annuloplasty (T: n = 12 vs non-T: n = 33). RV global longitudinal strain (RVGLS), RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), and early tricuspid inflow velocity/early diastolic tricuspid annular velocity ratio (tricuspid E/e') were assessed as functional indices at preoperative, postoperative and 1-year follow-up periods. RESULTS: RVFAC deteriorated postoperatively but recovered at follow-up in group T, whereas that in group non-T showed gradual deterioration overtime. RVGLS and TAPSE showed similar temporary deterioration and recovery between groups. Tricuspid E in group T increased postoperatively and showed significant difference, which was kept until follow-up period. Tricuspid e' decreased postoperatively, and recovered slightly in both groups. As a result, postoperative RV diastolic function (tricuspid E/e') showed significant difference between groups. This difference was maintained until follow-up. CONCLUSIONS: RV systolic function deteriorated postoperatively, but there was a tendency to improve at follow-up regardless of tricuspid annuloplasty. RV diastolic function may potentially be impaired when TR was regulated by tricuspid annuloplasty.
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Diástole , Ventrículos do Coração/fisiopatologia , Anuloplastia da Valva Mitral , Complicações Pós-Operatórias/fisiopatologia , Sístole , Insuficiência da Valva Tricúspide/fisiopatologia , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/cirurgia , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Direita , Idoso , Velocidade do Fluxo Sanguíneo , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Valva Tricúspide/fisiopatologiaRESUMO
Computed tomography(CT) is indispensable for diagnostic imaging. During preoperative assessment for cardioaortic surgery, a CT examination is performed not only for diagnostic purposes but also to decide the surgical strategy. In some cases, CT demonstrates a small abnormal mass in the adipose tissue of the anterior mediastinum. Sometimes radiologists diagnose the image and send the diagnostic report to cardiologists or cardiovascular surgeons. However, they tend to limit their focus to their field of specialty. Thus, they might overlook or underestimate an abnormal mass. Anterior mediastinal masses, though small, may include malignant tumors. Thus, we reviewed 12 cases in which anterior mediastinal masses were found on preoperative CT. Two of these patients were finally diagnosed with malignant tumors. We should pay attention to not only cardiovascular assessment but also mediastinal masses on preoperative CT. In some cases, concomitant surgery for cardioaortic disease and an anterior mediastinal tumor is effective.
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Tomografia Computadorizada por Raios X , Humanos , Neoplasias do Mediastino , MediastinoRESUMO
Euglena gracilis has an organelle resembling hematochrome, with an appearance similar to the eyespot and the absorption band spectrally overlapped with that of the carotenoid. To discriminate the hematochrome-like granules and eyespot, scan-free, non-invasive, absorbance spectral imaging A(x, y, λ) microscopy of single live cells, where A(x, y, λ) means absorbance at a position (x, y) on a two-dimensional image at a specific wavelength λ was applied. This technique was demonstrated to be a powerful tool for basic research on intracellular structural analysis. By this method, characteristic absorption spectra specific to the hematochrome-like granule or eyespot were identified among a variety of spectra observed depending on the location inside the organelles. The hematochrome-like granule was dark orange and deep green in its outline and had a characteristic absorption peak at 620 nm as well as at 676 to 698 nm, suggesting that its origin is a component of chloroplast including chlorophyll a. Furthermore, the representative spectra of these organelles were derived by principal component analysis of the absorbance and its position in absorbance image, indicating that they can be distinguished from each other and other regions. It was also confirmed that even in areas where these organelles and chloroplasts overlap, one can distinguish them from each other. The present research clarified the absorption spectra of the eyespot with 1 × 1 µm spatial resolution and those unpublished of hematochrome-like granules of E. gracilis, and indicated that one can statistically distinguish these organelles by this method.
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Euglena gracilis/metabolismo , Organelas/metabolismo , Animais , Euglena gracilis/fisiologia , Microscopia Intravital , Microespectrofotometria , Organelas/fisiologia , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras/fisiologiaRESUMO
BACKGROUND Chronic mesenteric ischemia (CMI) is defined as ischemic symptoms caused by insufficient supply of blood to the gastrointestinal tract. Patients diagnosed with advanced symptomatic CMI should be treated subsequently, as the transition from CMI to acute mesenteric ischemia can be unpredictable. However, there is little information regarding the management of potential procedural complications during endovascular therapy (EVT) for CMI. CASE REPORT A 70-year-old man was admitted to our hospital with recurrent abdominal pain just after hemodialysis. The angiogram showed significant stenosis with heavy calcification in the proximal of the superior mesenteric artery (SMA), leading to the diagnosis of CMI. To alleviate the symptom, EVT for the stenotic lesion of the SMA was indicated. During the procedure, a cutting balloon was inflated to facilitate vessel expansion in the target lesion. As a result, intravascular ultrasound (IVUS) imaging revealed dissection into the media with extension into the medial space without reentry and demonstrated a semilunar intramural hematoma. We were able to contain the intramural hematoma by covering the whole dissection in the SMA with implantation of self-expandable stents. CONCLUSIONS This case highlights the potential of EVT for heavy calcification of the SMA complicated by dissection without reentry. Intramural hematoma was observed with IVUS examination. We were able to contain the hematoma by the implantation of self-expandable stents over the whole length of the SMA dissection under IVUS-guided EVT.
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Isquemia Mesentérica , Oclusão Vascular Mesentérica , Masculino , Humanos , Idoso , Artéria Mesentérica Superior/diagnóstico por imagem , Isquemia Mesentérica/diagnóstico por imagem , Isquemia Mesentérica/etiologia , Isquemia Mesentérica/terapia , Intestinos , Ultrassonografia , Doença Crônica , Isquemia , Stents , Resultado do TratamentoRESUMO
Objective To determine whether nutritional status is related to the incidence of thrombosis and mortality in patients with Coronavirus disease 2019 (COVID-19). Methods A total of 496 consecutive patients who were admitted and diagnosed with COVID-19 between April 2020 and March 2023 were retrospectively analyzed. The geriatric nutritional risk index (GNRI) on admission was calculated as follows: 14.89×serum albumin (g/dL) +41.7×body mass index/22. Patients were divided into two groups according to the median GNRI values. The endpoint of this study was a composite of in-hospital thrombotic events and mortality. Results The median GNRI value was 99.3. Patients in the low GNRI (≤99.3) group were older (75±21 vs. 51±20 years, p<0.001) and more likely to be female (55.6% vs. 41.1%, p<0.05). In addition, patients with a low GNRI often exhibited hypertension (43.5% vs. 28.2%, p<0.001) and had a history of cardiovascular disease (34.3% vs. 14.5%, p<0.001). Under these conditions, the median D-dimer levels on admission were significantly higher in patients with a low GNRI (0.90 µg/mL; IQR, 0.49-1.64 µg/mL) than those with high GNRI (0.36 µg/mL; IQR, 0.26-0.51 µg/mL, p<0.001). During hospitalization, the composite endpoint was observed in 32 patients. In the logistic regression analysis, a low GNRI was significantly associated with the composite endpoint adjusted using inverse probability of treatment weighting (odds ratio, 3.24; 95% confidence interval: 1.51-6.93, p<0.05). Conclusion Assessment of the GNRI provides useful information for predicting in-hospital thrombosis and mortality in COVID-19 patients.
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Although the phenomenon of collective order formation by cell-cell interactions in motile cells, microswimmers, has been a topic of interest, most studies have been conducted under conditions of high cell density, where the space occupancy of a cell population relative to the space size Ï>0.1 (Ï is the area fraction). We experimentally determined the spatial distribution (SD) of the flagellated unicellular green alga Chlamydomonas reinhardtii at a low cell density (Ï≈0.01) in a quasi-two-dimensional (thickness equal to cell diameter) restricted space and used the variance-to-mean ratio to investigate the deviation from the random distribution of cells, that is, do cells tend to cluster together or avoid each other? The experimental SD is consistent with that obtained by Monte Carlo simulation, in which only the excluded volume effect (EV effect) due to the finite size of cells is taken into account, indicating that there is no interaction between cells other than the EV effect at a low cell density of Ï≈0.01. A simple method for fabricating a quasi-two-dimensional space using shim rings was also proposed.
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This paper presents an outdoors laser-based pedestrian tracking system using a group of mobile robots located near each other. Each robot detects pedestrians from its own laser scan image using an occupancy-grid-based method, and the robot tracks the detected pedestrians via Kalman filtering and global-nearest-neighbor (GNN)-based data association. The tracking data is broadcast to multiple robots through intercommunication and is combined using the covariance intersection (CI) method. For pedestrian tracking, each robot identifies its own posture using real-time-kinematic GPS (RTK-GPS) and laser scan matching. Using our cooperative tracking method, all the robots share the tracking data with each other; hence, individual robots can always recognize pedestrians that are invisible to any other robot. The simulation and experimental results show that cooperating tracking provides the tracking performance better than conventional individual tracking does. Our tracking system functions in a decentralized manner without any central server, and therefore, this provides a degree of scalability and robustness that cannot be achieved by conventional centralized architectures.
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Lasers , Robótica , Caminhada , Humanos , Modelos TeóricosRESUMO
In mammal circulation, ferritin-binding proteins (FBPs) are thought to be involved in clearance of circulating ferritin after complex formation with it through receptor-mediated uptake. However, there is no report on fetal FBP in fetal circulation. Although iron concentrations of fetal horse plasma were higher than those of adult horse plasma, plasma ferritin concentrations and ferritin-binding activities were found to be significantly lower in fetus than in adult. FBPs were purified from fetal or adult horse plasma on horse spleen ferritin-Sepharose 4B affinity column. Partially affinity-purified fetal horse plasma FBPs were mainly separated into 65 and 41 kDa bands in addition to minor bands with higher molecular masses ranged from 102 to 140 kDa on SDS-PAGE under reducing condition. The adult horse plasma FBPs were separated into 74, 54 and 28 kDa bands, and the 74 and 54 kDa bands reacted with antibodies specific for horse IgM and IgG heavy chains, respectively, by immunoblotting analyses. On the other hand, no antibodies to horse immunoglobulin classes detected any bands in fetal horse plasma FBPs. The affinity-purified adult and fetal horse plasma FBPs did not contain fibrinogen as a plasma specific FBP, probably due to its lower affinity to the ligand ferritin. These results demonstrate the presence of FBPs which are different from adult horse plasma FBPs including anti-ferritin autoantibodies in fetal plasma.
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BACKGROUND: Diastolic retrograde flow in the descending aorta (DAo) may occur in the presence of atherosclerosis and may be overlooked as a mechanism of retrograde embolization in patients with stroke. We performed thoracic endovascular aortic repair (TEVAR) in a patient with recurrent cerebral infarctions for treatment of aortic aneurysm with atheromatic plaque, which was considered as the source of embolism. CASE PRESENTATION: A 56-year-old man with a history of idiopathic thrombocytopenia and hypertension was referred to our hospital with paralysis of the right upper and lower limbs. Multiple cerebral infarctions were found and treated; however, 1 month later, another cerebral infarction developed. A small saccular aortic aneurysm with plaque was found beyond the left subclavian artery, and this site was deemed as the source of embolism. We performed TEVAR to prevent further recurrence of cerebral infarctions. No cerebral infarctions were observed 6 months post-operation. CONCLUSIONS: TEVAR is a useful treatment for not only aortic aneurysm and dissection, but also cerebral infarctions caused by an embolic source proximal to the DAo due to retrograde aortic blood flow.
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Total debranching thoracic endovascular aortic repair is useful for avoiding neurological complications in cases where cardiopulmonary bypass is difficult and for devising an intraoperative cervical branch reconstruction method.
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We describe a case of an elderly man with Citrobacter freundii-associated infectious rupture of a dissecting thoracoabdominal aortic aneurysm. We performed an emergency thoracoabdominal aortic replacement using a rifampicin-soaked prosthetic graft and omental flap wrapping. The patient was discharged on postoperative day 255, although he experienced pseudomembranous enteritis and paraplegia.
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OBJECTIVE: To clarify the living environment factors that increase the risk of allergic sensitization to house dust mites, we applied a regression binary tree-based method (CART, Classification & Regression Trees) to an epidemiological study on airway allergy. The utility of the tree map in personal sanitary guidance for preventing allergic sensitization was examined with respect to feasibility and validity. SUBJECTS AND METHODS: A questionnaire was given to 386 healthy adult women, asking them about their individual living environments. Also, blood samples were collected to measure Dermatophagoides pteronyssinus (Dp)-specific IgE, the presence/absence of Dp-sensitization being expressed as positive/negative. The questionnaire consisted of nine items on (1) home ventilation by keeping windows open, (2) personal or family smoking habits, (3) use of air conditioners in hot weather, (4) type of flooring (tatami/wooden/carpet) in the living room, (5) visible mold proliferation in the kitchen, (6) type of housing (concrete/wooden), (7) residential area (heavy or light traffic area) (8) heating system (use of unventilated combustion appliances), and (9) frequency of cleaning (every day or less often). There also were queries on the past history of airway allergic diseases, such as bronchial asthma and allergic rhinitis. CART and a multivariate logistic regression analysis (MLRA) were performed. The subjects were first classified into two groups, with and without a history of airway allergic diseases (Groups WPH and WOPH). In each group, the involvement of living environment factors in Dp-sensitization was examined using CART and MLRA. RESULTS: In the MLRA study, individual living environment factors showed promotional or suppressive effects on Dp-sensitization with differences between the two groups. With respect to the CART results, the two groups were first split by the factor that had the most significant odds ratio for MLRA. In Group WPH, which had a Dp-sensitization risk of 19.5%, the first split was by the factor of visible mold proliferation in the kitchen into the factor-present group with a risk value of 45.5% and the factor-absent group with 13.5%. The mold proliferation group was split with reference to frequent cleaning, and the risk rose to 75% in the factor-absent group and to 100% when family smoking habits were reported. Group WOPH (the risk: 10.8%) was first split into two groups according to the use of air conditioners in hot weather for more than 6 hours a day or less, which showed risk values of 16.7% and 6.9%, respectively. The risk of the group that intensively used air conditioners fell to 8.3% with tatami as flooring in the living room, and, if others, rose to 20.8%. The risk of the factor-lacking group fell to 4.0% without wooden flooring. CONCLUSIONS: CART analysis enables us to express complex relationships between living environment factors and Dp-sensitization simply by a binary regression tree, pointing to preventive strategies that can be flexibly changed according to the individual living environments of the subjects.
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Meio Ambiente , Pyroglyphidae/imunologia , Hipersensibilidade Respiratória/etiologia , Feminino , Humanos , Análise Multivariada , Inquéritos e QuestionáriosRESUMO
OBJECTIVES: The involvement of tightly insulated housing conditions and passive smoking in atopic sensitization, a major risk factor for airway allergy, was examined with nonsmoking adult women and school-age children. SUBJECTS AND METHODS: The subjects were 382 nonsmoking healthy adult women (housewives) who underwent medical examinations for prevention of adult diseases conducted in a district of Osaka from 1995 to 1997, and 214 elementary school-children 9-12 years old living in an urban district of Osaka who underwent medical examinations at a health center in April, 2000 to prevent allergic diseases. We also examined the correlation between tightly insulated housing conditions and the amount of passive smoking based on family smoking habits with 170 children under 12 years old who had been under the care of a hospital pediatrics department between December, 1993 and May, 1994. A questionnaire was administered to all subjects to survey the housing structure (concrete/wooden housing), family smoking habits and visible mold proliferation in the kitchen in relation to airtight housing conditions, passive smoking and exposure to inhalant allergens. Atopic sensitization was assessed by positivity for serum house dust mite-specific IgE, and passive smoking was defined as a urinary cotinine level of more than 6 ng/mgCr. RESULTS: 1. Among the three factors, indoor mold proliferation and family smoking habits were positively and synergistically related with atopic sensitization to house dust mites. 2. Airtight conditions of concrete housing showed a promotional effect on passive smoking for housewives, but a suppressive effect for school-age children. 3. Taking into account the above results, the promotional effects of passive smoking on atopic sensitization appeared predominantly in the concrete housing-residence group of housewives and the wooden housing-residence group of school-age children. 4. Effects of visible mold proliferation in the kitchen on atopic sensitization appeared predominantly in wooden housing-residence group of housewives. CONCLUSIONS: The results suggest that involvement of the three factors in atopic sensitization is due to increased exposure to indoor inhalant allergens or enhanced IgE-antibody production (adjuvant effects of tobacco smoke) and the extent of their inpact varies depending on the individual life styles of the housewives and school-age children.
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Habitação , Hipersensibilidade Imediata/etiologia , Pyroglyphidae/imunologia , Hipersensibilidade Respiratória/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Idoso , Poluição do Ar em Ambientes Fechados/efeitos adversos , Criança , Feminino , Humanos , Imunoglobulina E/sangue , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
A 67-year-old man who had a history of syncope was admitted because of effort angina. The sinus node (SN) was the single blood supply from the right coronary artery (RCA). After we implanted 2 everolimus-eluting stents for RCA, slow-flow occurred and the SN artery was occluded, and junctional escape rhythm was sustained. After the wiring to the occluded SN artery, junctional escape rhythm immediately recovered to sinus rhythm, and the patient achieved continuous sinus rhythm and stable hemodynamics. Given that acute SN ischemia is a possible cause of sinus dysfunction, careful choice of a percutaneous coronary intervention strategy should be taken into consideration if the SN artery is the single blood supply from the RCA and if syncopal history is present.
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Angina Pectoris/terapia , Angioplastia Coronária com Balão/efeitos adversos , Doença da Artéria Coronariana/terapia , Stents Farmacológicos/efeitos adversos , Parada Sinusal Cardíaca/fisiopatologia , Parada Sinusal Cardíaca/terapia , Idoso , Angina Pectoris/etiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/fisiopatologia , Humanos , Masculino , Radiografia , Fatores de Risco , Parada Sinusal Cardíaca/etiologiaRESUMO
Sequential arrays of chromophores at regulated distances were constructed on a noncovalent DNA molecular assembly system in aqueous media. Photoinduced fluorescence resonance energy transfer (FRET) behaviors were then observed. We designed a number of chromophore/oligo-DNA conjugates with varying sequences. The chromophores eosin (Eo), TexasRed (TR), and tetramethylrhodamine (Rho) were employed as the energy donor, acceptor, and mediator, respectively, based on overlapping excitation and emission spectra. The chromophores were attached via aminolinkers to the 5'-terminals of 10mer oligo-DNAs consisting of AT rich sequences. The arrangement of Eo-Rho or Rho-TR with 10-residue (1 pitch of duplex) distances was ensured by duplex formation of the conjugates with a 20mer matrix oligo-DNA composed of complementary sequences to the conjugates. Single-step FRET from Eo to Rho and from Rho to TR was confirmed on the duplex. The three chromophore conjugates were then mixed with longer matrix oligo-DNAs (30 or 40mer) consisting of complementary sequences to the conjugates, producing Eo-(Rho)(n)-TR (n = 1 or 2) arrays with 10-residue distances. Multistep FRET from Eo to TR through the Rho mediator(s) was observed on the molecular assemblies. This photoenergy transmission system offers a good model for a photoenergy transmission system mimicking photosynthetic systems.
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DNA/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Sequência de Bases , Amarelo de Eosina-(YS)/química , Dados de Sequência Molecular , Estrutura Molecular , Oligonucleotídeos/química , Rodaminas/química , Espectrometria de Fluorescência , Xantenos/químicaRESUMO
Tissue-specific induction of mRNA of cytochrome P450 (P450 or CYP) 1A1 and 1B1 by polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) was investigated in wild and arylhydrocarbon receptor (AhR)-deficient C57BL/6J mice. Ratios of mRNA expression of CYP1A1 or CYP1B1 over beta-actin were determined and used to compare levels of expression and induction of these P450s by PAHs and PCBs in various organs. CYP1A1 mRNA was detected in control mice at very low levels in liver, lung, heart, kidney, intestine, thymus, testis, uterus, ovary, and brain and was highly induced in these organs by benzo[a]pyrene and 3,4,3',4'-tetrachlorobiphenyl in AhR(+/+) mice. In AhR(+/+) and AhR(-/-) mice, CYP1B1 mRNA was found to be constitutively expressed at significant levels in heart (the ratio of mRNAs of CYP1B1 to beta-actin was approximately 0.6), kidney ( approximately 0.8), intestine ( approximately 0.3), testis ( approximately 0.9), thymus ( approximately 0.4), uterus ( approximately 0.3), ovary ( approximately 1.4), and brain ( approximately 0.4), whereas it was low in liver and lung (the mRNA ratio to beta-actin was <0.2 in these cases). CYP1B1 in the latter two organs was highly induced by PAHs and 3,4,3',4'-tetrachlorobiphenyl in AhR(+/+) mice. The induction of CYP1B1 by PAHs and PCBs was more extensive in organs in which the constitutive expression of CYP1B1 was low. For example, CYP1B1 was induced 9-fold and 10-fold by benzo[a]pyrene and 3,4,3',4'-tetrachlorobiphenyl in livers of male and female mice, respectively, whereas in testis and ovary, the fold induction of CYP1B1 by two inducers was only 1.1 and 1.4, respectively. Liver microsomal xenobiotic oxidation activities were induced by these PAHs and PCBs in male and female AhR(+/+) mice. These results suggest that CYP1A1 and CYP1B1 are differentially regulated in their expression in extrahepatic organs of mice and could be induced by PAHs and PCBs with different extents of induction depending on the inducers used and the organs examined in AhR(+/+) mice. The findings of significant levels of constitutive expression of CYP1B1 in AhR(-/-) mice as well as AhR(+/+) mice in several organs including heart, kidney, thymus, testis, ovary, and brain in AhR(-/-) mice as well as AhR(+/+) mice are of importance in understanding the basis of toxicity and carcinogenesis by chemicals that are metabolized by CYP1B1.
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Hidrocarboneto de Aril Hidroxilases/biossíntese , Citocromo P-450 CYP1A1/biossíntese , Microssomos Hepáticos/efeitos dos fármacos , Bifenilos Policlorados/farmacologia , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Actinas/metabolismo , Animais , Citocromo P-450 CYP1B1 , Indução Enzimática/efeitos dos fármacos , Feminino , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/enzimologia , RNA Mensageiro/biossíntese , Receptores de Hidrocarboneto Arílico/deficiência , Receptores de Hidrocarboneto Arílico/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Arylhydrocarbon receptor knock-out, AhR(-/-), mice have recently been shown to be rather resistant to benzo[a]pyrene (B[a]P)-induced tumor formation, probably reflecting the inability of these mice to express significant levels of cytochrome P450 (P450 or CYP) 1A1 that activates B[a]P to reactive metabolites (Y. Shimizu, Y. Nakatsuru, M. Ichinose, Y. Takahashi, H. Kume, J. Mimura, Y. Fujii-Kuriyama and T. Ishikawa (2000) PROC: Natl Acad. Sci. USA, 97, 779-782). However, it is not precisely determined whether CYP1B1, another enzyme that is also active in activating B[a]P, plays a role in the B[a]P carcinogenesis in mice. To understand the basis of roles of CYP1A1 and CYP1B1 in the activation of chemical carcinogens, we compared levels of induction of liver and lung CYP1A1, 1A2, and 1B1 by various polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls in AhR(+/+) and AhR(-/-) mice. Liver and lung CYP1A1 and 1B1 mRNAs were highly induced in AhR(+/+) mice by a single intraperitoneal injection of each of the carcinogenic PAHs, such as B[a]P, 7,12-dimethylbenz[a]anthracene, dibenz[a,l]pyrene, 3-methylcholanthrene, 1,2,5,6-dibenzanthracene, benzo[b]fluoranthene, and benzo[a]anthracene and by a co-planar PCB congener 3,4,3',4'-tetrachlorobiphenyl. We also found that 6-aminochrysene, chrysene, benzo[e]pyrene, and 1-nitropyrene weakly induced the mRNA expression of CYP1A1 and 1B1, whereas anthracene, pyrene, and fluoranthene that have been reported to be non-carcinogenic in rodents, were very low or inactive in inducing these P450s. The extents of induction of liver CYP1A2 by these chemicals were less than those of CYP1A1 and 1B1 in AhR(+/-/+/-) mice. In AhR(-/-) mice, there was no induction of these P450s by PAHs and polychlorinated biphenyls. Liver microsomal activities of 7-ethoxyresorufin and 7-ethoxycoumarin O-deethylations and of mutagenic activation of (+/-)-trans-7,8-dihydroxy-7,8-dihydro-B[a]P to DNA-damaging products were found to correlate with levels of CYP1A1 and 1B1 mRNAs in the liver. Our results suggest that carcinogenicity potencies of PAHs may relate to the potencies of these compounds to induce CYP1A1 and 1B1 through AhR-dependent manner and that these induced P450s participate in the activation of B[a]P and related carcinogens causing initiation of cancers in mice.