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1.
J Acoust Soc Am ; 149(1): 591, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33514124

RESUMO

Mt. Shinmoedake, a part of the Mt. Kirishima cluster of volcanoes in Kyushu, Japan, erupted on 10 March 2018. Our infrasound sensor network located at a distance of more than 200 km from the source detected signals emitted by an explosive eruption of Mt. Shinmoedake. The arrival time of the signals is divided into three time intervals. To reveal how the observed infrasound signals propagated from the source to the sensors, we carry out three-dimensional ray tracing on the basis of the Hamilton equations including the vertical profiles of the temperature and wind around the ray path. We present formulas for calculating travel time and distance of infrasound from a source to an observation site and its turning altitude in the atmosphere. We have identified four kinds of signals, namely, the waves propagated in the troposphere undergoing multiple refraction and those refracting from the stratosphere, the mesosphere, and the lower thermosphere. Brief discussion is devoted to some of the unidentified signals.

2.
Arch Toxicol ; 94(9): 3231-3247, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32656655

RESUMO

In the case of a nuclear power plant accident, repetitive/prolonged radioiodine release may occur. Radioiodine accumulates in the thyroid and by irradiation enhances the risk of cancer. Large doses of non-radioactive iodine may protect the thyroid by inhibiting radioiodine uptake into the gland (iodine blockade). Protection is based on a competition at the active carrier site in the cellular membrane and the Wolff-Chaikoff effect, the latter being, however, only transient (24-48 h). Perchlorate may alternatively provide protection by a carrier competition mechanism only. Perchlorate has, however, a stronger affinity to the carrier than iodide. Based on an established biokinetic-dosimetric model developed to study iodine blockade, and after its extension to describe perchlorate pharmacokinetics and the inhibition of iodine transport through the carrier, we computed the protective efficacies that can be achieved by stable iodine or perchlorate in the case of an acute or prolonged radioiodine exposure. In the case of acute radioiodine exposure, perchlorate is less potent than stable iodine considering its ED50. A dose of 100 mg stable iodine has roughly the same protective efficacy as 1000 mg perchlorate. For prolonged exposures, single doses of protective agents, whether stable iodine or perchlorate, offer substantially lower protection than after acute radioiodine exposure, and thus repetitive administrations seem necessary. In case of prolonged exposure, the higher affinity of perchlorate for the carrier in combination with the fading Wolff-Chaikoff effect of iodine confers perchlorate a higher protective efficacy compared to stable iodine. Taking into account the frequency and seriousness of adverse effects, iodine and perchlorate at equieffective dosages seem to be alternatives in case of short-term acute radioiodine exposure, whereas preference should be given to perchlorate in view of its higher protective efficacy in the case of longer lasting radioiodine exposures.


Assuntos
Radioisótopos do Iodo/toxicidade , Iodo/farmacologia , Percloratos/farmacologia , Exposição à Radiação , Protetores contra Radiação/farmacologia , Glândula Tireoide/fisiologia , Humanos
3.
Proc Jpn Acad Ser B Phys Biol Sci ; 95(4): 165-177, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30971619

RESUMO

A comprehensive geochemical study of the Chelyabinsk meteorite reveals further details regarding its history of impact-related fragmentation and melting, and later aqueous alteration, during its transit toward Earth. We support an ∼30 Ma age obtained by Ar-Ar method (Beard et al., 2014) for the impact-related melting, based on Rb-Sr isotope analyses of a melt domain. An irregularly shaped olivine with a distinct O isotope composition in a melt domain appears to be a fragment of a silicate-rich impactor. Hydrogen and Li concentrations and isotopic compositions, textures of Fe oxyhydroxides, and the presence of organic materials located in fractures, are together consistent with aqueous alteration, and this alteration could have pre-dated interaction with the Earth's atmosphere. As one model, we suggest that hypervelocity capture of the impact-related debris by a comet nucleus could have led to shock-wave-induced supercritical aqueous fluids dissolving the silicate, metallic, and organic matter, with later ice sublimation yielding a rocky rubble pile sampled by the meteorite.


Assuntos
Meteoroides , Água/química , Planeta Terra , Evolução Planetária
4.
Nihon Jibiinkoka Gakkai Kaiho ; 118(9): 1124-32, 2015 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-26615663

RESUMO

BACKGROUND: Persons allergic to birch pollen often report oral and pharyngeal hypersensitivity to fruit and vegetables, due to immunological cross-reactivity between pollen and foods. This phenomenon is referred to as the oral allergy syndrome (GAS). Such cross-reactive antigen reactions mainly involve Bet v 1, which is the major birch-pollen allergen, and partially involve birch-pollen profilin Bet v 2. Soybean contains Bet v 1-related antigen (Gly m 4), and soy milk often causes the OAS with severe symptoms such as precordial and abdominal burning sensation because soy milk undergoes little denaturation, and this water-soluble liquid is consumed by most people rather quickly. We evaluated the frequency of the oAS after ingestion of soymilk and examined IgE antibodies to various allergens. METHODS: A total of 167 patients [122 women, 45 men; age range, 4-72 years (mean age, 32 years)], who had experienced GAS episodes and had IgE birch--pollen antibodies, were interviewed. Using the CAP system, we examined IgE antibodies to birch pollen and other allergens. Of 167 patients, 161 were examined for IgE antibodies to Bet v 1, Bet v 2, Gly m 4, and soybean. We evaluated the frequency of the GAS after soy milk ingestion based on reports by GAS patients with birch pollen allergy, and evaluated the positive rates of some of the IgE antibodies. RESULTS: Among the 167 patients with birch-pollen allergy and GAS on ingestion of any of the foods, there were 16 cases (10%) with OAS following soy milk ingestion. In addition, the foods that caused OAS most often were apples (123 cases, 74%), peaches (67%), and cherries (55%), followed by pears (37%) and kiwi (37%). A higher CAP class for birch pollen, Bet v 1, Gly m 4, and soybean was associated with a higher prevalence of OAS to soy milk. Of 15 patients who had GAS on ingestion of soy milk and had birch-pollen allergy, 47% (7cases) were CAP class 1 for soybean and only 7% (case) was CAP class c2, whereas 93% (14cases) were CAP class 1 for Gly m 4, and 87% (3cases) were CAP class ≥ 2 for Gly m 4. CONCLUSION: Among the birch-pollen allergic OAS patients, 10% had the OAS on ingestion of soy milk, and among these with birch-pollen allergy and the OAS on ingestion of soy milk, the positive rate for soy milk CAP was low, whereas that for Gly m 4 CAP was high.


Assuntos
Betula/imunologia , Hipersensibilidade Alimentar/imunologia , Rinite Alérgica Sazonal/imunologia , Leite de Soja , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Reações Cruzadas , Feminino , Hipersensibilidade Alimentar/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Rinite Alérgica Sazonal/complicações
5.
Nihon Jibiinkoka Gakkai Kaiho ; 117(5): 653-7, 2014 May.
Artigo em Japonês | MEDLINE | ID: mdl-24956742

RESUMO

Occurrence of airborne pollen in Sapporo has been studied for 19 years during the period between 1995 and 2013. There are wide year-to-year variations in the quantities of birch pollens. A simple linear regression with the least squares method was used for studying correlations between the annual quantities of birch pollens and the meteorological factors. A significant positive correlation was found between the hours of sunlight in June of the preceding year and the annual birch pollen concentrations with the correlation coefficient, R = 0.667. Also, we found the significant positive correlation between the hours of sunlight in March and the annual birch pollen concentrations with the correlation coefficient, R = 0.684. These results suggest that the atmospheric birch pollen counts can be predicted from meteorological factors.


Assuntos
Alérgenos/imunologia , Betula/crescimento & desenvolvimento , Pólen/crescimento & desenvolvimento , Rinite Alérgica Sazonal/imunologia , Tempo (Meteorologia) , Betula/imunologia , Humanos , Japão , Fotoperíodo , Pólen/imunologia , Estações do Ano
6.
Int J Qual Health Care ; 25(4): 418-28, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23736833

RESUMO

OBJECTIVE: To develop a set of process-of-care quality indicators (QIs) that would cover a wide range of gastric cancer care modalities and to examine the current state of the quality of care provided by designated cancer care hospitals in Japan. DESIGN: A retrospective medical record review. SETTING: Eighteen designated cancer care hospitals throughout Japan. PARTICIPANTS: A total of 1685 patients diagnosed with gastric cancer in 2007. MAIN OUTCOME MEASURES: Provision of care to eligible patients as described in the 29 QIs, which were developed using an adaptation of the RAND/UCLA (University of California, Los Angeles) appropriateness method by a panel of nationally recognized experts in Japan. RESULTS: Overall, the patients received 68.3% of the care processes recommended by the QIs. While 'deep venous thrombosis prophylaxis before major surgery' was performed for 99% of the cases, 'documentation before endoscopic resection' was completed for only 12% of the cases. The chemotherapy care was less likely to meet the QI standards (61%) than pre-therapeutic care (76%), surgical treatment (66%) and endoscopic resection (71%; overall difference: P < 0.001). A comparison based on the types of care showed that documentation and patient explanation were performed less frequently (60 and 53%, respectively) than were diagnostic and therapeutic processes as recommended in the QIs (85%; overall P < 0.001). CONCLUSIONS: Although many required care processes were provided, some areas with room for improvement were revealed, especially with respect to chemotherapy, documentation and patient explanation. Continuous efforts to improve the quality and develop a system to monitor this progress would be beneficial in Japan.


Assuntos
Institutos de Câncer/organização & administração , Qualidade da Assistência à Saúde/organização & administração , Neoplasias Gástricas/terapia , Idoso , Institutos de Câncer/normas , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Avaliação de Processos em Cuidados de Saúde , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde/normas , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia
7.
Int J Mol Sci ; 14(10): 19618-35, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24084715

RESUMO

The development of an effective therapy for radiation-induced gastrointestinal damage is important, because it is currently a major complication of treatment and there are few effective therapies available. Although we have recently demonstrated that pretreatment with ascorbic acid attenuates lethal gastrointestinal damage in irradiated mice, more than half of mice eventually died, thus indicating that better approach was needed. We then investigated a more effective therapy for radiation-induced gastrointestinal damage. Mice receiving abdominal radiation at 13 Gy were orally administered ascorbic acid (250 mg/kg/day) for three days before radiation (pretreatment), one shot of engulfment (250 mg/kg) at 8 h before radiation, or were administered the agent for seven days after radiation (post-treatment). None of the control mice survived the abdominal radiation at 13 Gy due to severe gastrointestinal damage (without bone marrow damage). Neither pretreatment with ascorbic acid (20% survival), engulfment (20%), nor post-treatment (0%) was effective in irradiated mice. However, combination therapy using ascorbic acid, including pretreatment, engulfment and post-treatment, rescued all of the mice from lethal abdominal radiation, and was accompanied by remarkable improvements in the gastrointestinal damage (100% survival). Omitting post-treatment from the combination therapy with ascorbic acid markedly reduced the mouse survival (20% survival), suggesting the importance of post-treatment with ascorbic acid. Combination therapy with ascorbic acid may be a potent therapeutic tool for radiation-induced gastrointestinal damage.


Assuntos
Ácido Ascórbico/farmacologia , Raios gama/efeitos adversos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos da radiação , Animais , Radicais Livres/metabolismo , Trato Gastrointestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
Nihon Jibiinkoka Gakkai Kaiho ; 116(7): 779-88, 2013 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-23980483

RESUMO

BACKGROUND: In Hokkaido and Scandinavia, birch pollen allergic persons are common and they often report oral and pharyngeal hypersensitivity to fruits and vegetables (oral allergy syndrome, OAS), because of immunological cross-reactivity. In Scandinavia, nuts as well as Rosaceae fruits such as apples were the foods most often reported to elicit symptoms. On the other hand, nuts are minor foods causing hypersensitivity in Japan. Even in Japan, regional differences of foods causing hypersensitivity have been reported, which may be related to the regional differences of elementary habit and pollen dispersion. In the present study, we evaluated the intake history of the foods and the frequency of food hypersensitivity in adults from the general population. METHODS: Three hundreds and thirty nine subjects (20-67 years old) took part in the study. With a questionnaire survey, we asked them about their intake history and hypersensitive symptoms for 33 kinds of fruit, vegetables, and nuts. RESULTS: 30% of subjects had eaten Brazil nuts, 80% had eaten pomegranates, and 81% had eaten hazelnuts. And over 95% of subjects had eaten the other 30 foods. Those who had lived in Hokkaido for more than 20 years had a higher frequency of plum consumption than the others. Those who had lived in Hokkaido for more than 20 years had a lower frequency of loquat, fig and pomegranate consumption than the others. Food hypersensitivity was found in 52 subjects (15.3%). The most common symptom was OAS (46 subjects, 13.6%), and foods most frequently causing OAS were peach (21 subjects, 6.2%), cherry (19 subjects, 5.6%) and apple (17 subjects, 5.0%). 26 subjects (7.7%) reported OAS to Rosaceae fruits. The ratio of having OAS to consuming Rosaceae fruits was 11.0% in the group who had lived in Hokkaido for more than 20 years, which was higher than the group who has lived in Hokkaido for less than 20 years. The intake history of hazelnuts and Brazil nuts was very low, with a correspondingly low frequency of food hypersensitivity associated with these nuts. CONCLUSION: The frequency of intake and hypersensitivity of some foods differ among different regions.


Assuntos
Betula/imunologia , Hipersensibilidade Alimentar/etiologia , Frutas/imunologia , Pólen/imunologia , Verduras/imunologia , Adulto , Idoso , Corylus/imunologia , Dieta , Feminino , Humanos , Masculino , Malus/imunologia , Pessoa de Meia-Idade , Nozes/imunologia , Prunus/imunologia , Inquéritos e Questionários
9.
Int J Radiat Biol ; 98(5): 831-842, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34762000

RESUMO

PURPOSE: In the case of a nuclear incident, the release of radioiodine must be expected. Radioiodine accumulates in the thyroid and by irradiation enhances the risk of cancer. Large doses of stable (non-radioactive) iodine may inhibit radioiodine accumulation and protect the thyroid ('thyroid blocking'). Protection is based on a competition at the active carrier site in the cellular membrane and an additional temporary inhibition of the organification of iodide (Wolff-Chaikoff effect). Alternatively, other agents like e.g. perchlorate that compete with iodide for the uptake into the thyrocytes may also confer thyroidal protection against radioiodine exposure.Biokinetic models for radioiodine mostly describe exchanges between compartments by first order kinetics. This leads to correct predictions only for low (radio)iodide concentrations. These models are not suited to describe the kinetics of iodine if administered at the dosages recommended for thyroid blocking and moreover does not permit to simulate either the protective competition mechanism at the membrane or the Wolff-Chaikoff effect. Models adapted for this purpose must be used. Such models may use a mathematical relation between the serum iodide concentration and a relative uptake suppression or a dependent rate constant determining total thyroidal radioiodine accumulation. Alternatively, the thyroidal uptake rate constant may be modeled as a function of the total iodine content of the gland relative to a saturation amount. Newer models integrate a carrier-mechanism described by Michalis-Menten kinetics in the membrane and in analogy to enzyme kinetics apply the rate law for monomolecular irreversible enzyme reactions with competing substrates to model the competition mechanism. An additional total iodide uptake block, independent on competition but limited in time, is used to simulate the Wolff-Chaikoff effect. CONCLUSION: The selection of the best model depends on the issue to be studied. Most models cannot quantify the relative contributions of the competition mechanism at the membrane and the Wolff-Chaikoff effect. This makes it impossible or exceedingly difficult to simulate prolonged radioiodine exposure and the effect of repetitive administrations of stable iodine. The newer thyroid blocking models with a separate modeling of competition and Wolff-Chaikoff effect allow better quantitative mechanistic insights and offer the possibility to simulate complex radioiodine exposure scenarios and various protective dosage schemes of stable iodine relatively easily. Moreover, they permit to study the protective effects of other competitors at the membrane carrier site, like e.g. perchlorate, and to draw conclusions on their protective efficacy in comparison to stable iodine.


Assuntos
Iodo , Glândula Tireoide , Iodetos/farmacologia , Iodo/farmacologia , Radioisótopos do Iodo , Percloratos/farmacologia
10.
Int J Radiat Biol ; 98(5): 942-957, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34871138

RESUMO

PURPOSE: Ascorbic acid is a strong antioxidant and has potent radioprotective effects on radiation injuries. Ascorbic acid 2-glucoside (AA2G) is a stabilized derivative of ascorbic acid and rapidly hydrolyzed into ascorbic acid and glucose. Since there is the possibility that AA2G treatment interferes with the antitumor activity of radiotherapy, we investigated the effect of AA2G treatment during radiotherapy on acute radiation enteritis and antitumor activity of radiotherapy in rats. MATERIALS AND METHODS: AY-27 rat bladder tumor cells were used to induce bladder tumors in rats. Two weeks after inoculation rats received fractionated pelvic radiotherapy in eight fractions for 4 weeks totaling 40 Gy. During radiotherapy, one group of rats received per os AA2G (ascorbic acid: 250 mg/kg/day) and its bolus engulfment (ascorbic acid: 250 mg/kg) 8 h before each X-irradiation fraction. Seven days after the last X-irradiation, we studied histology, DNA double strand break (DSB) damage (by 53BP1 foci staining), and the M1/M2 macrophage response by immunohistochemistry of paraffin-fixed bladder and intestinal tissues. RESULTS: AA2G treatment reduced the intestinal damage (shortening of villi) but did not reduce antitumor effectiveness of radiotherapy against bladder tumors. Like the controls, AA2G-treated rats showed no residual tumor lesions in the bladder after X-irradiation. Both AA2G-treated and control groups showed similar persistent DSB damage (53BP1 foci) both in bladders and ilea seven days after radiotherapy. Radiotherapy tended to reduce CD163+ M2 macrophages, which are considered as an anti-inflammatory subtype favoring tissue repair, in the bladders. X-irradiation also reduced the occurrence of M2 macrophages in the ilea. AA2G treatment significantly increased CD163+/CD68+ macrophage ratio in the ilea of rats after pelvic irradiation in comparison to the sham irradiated control rats. AA2G treatment increased, albeit not significantly, the CD163+/CD68+ macrophage ratio in the irradiated bladders relative to the control irradiated rats. On the other hand, bladders and ilea of the irradiated rats with and without AA2G treatment showed similar frequencies of CD68+ macrophages. CONCLUSIONS: AA2G treatment mitigated radiation-induced intestinal damage without reducing antitumor activity after fractionated pelvic radiotherapy against bladder tumors in rats. The beneficial effect of AA2G treatment seems to promote a restoration of the M2 answer as well as tissue remodeling and wound healing. Similar residual DNA damage in bladders and ilea seven days post-irradiation is consistent with tumor control in both groups.


Assuntos
Neoplasias da Bexiga Urinária , Animais , Antioxidantes , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/farmacologia , Feminino , Glucosídeos , Humanos , Masculino , Ratos , Neoplasias da Bexiga Urinária/radioterapia
11.
J Allergy Clin Immunol Pract ; 10(10): 2667-2676.e10, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35953016

RESUMO

BACKGROUND: With the implementation of mass vaccination campaigns against COVID-19, the safety of vaccine needs to be evaluated. OBJECTIVE: We aimed to assess the incidence and risk factors for immediate hypersensitivity reactions (IHSR) and immunization stress-related responses (ISRR) with the Moderna COVID-19 vaccine. METHODS: This nested case-control study included recipients who received the Moderna vaccine at a mass vaccination center, Japan. Recipients with IHSR and ISRR were designated as cases 1 and 2, respectively. Controls 1 and 2 were selected from recipients without IHSR or ISRR and matched (1 case: 4 controls) with cases 1 and cases 2, respectively. Conditional logistic regression analysis was used to identify risk factors associated with IHSR and ISRR. RESULTS: Of the 614,151 vaccine recipients who received 1,201,688 vaccine doses, 306 recipients (cases 1) and 2478 recipients (cases 2) showed 318 events of IHSR and 2558 events of ISRR, respectively. The incidence rates per million doses were estimated as IHSR: 266 cases, ISRR: 2129 cases, anaphylaxis: 2 cases, and vasovagal syncope: 72 cases. Risk factors associated with IHSR included female, asthma, atopic dermatitis, thyroid diseases, and a history of allergy; for ISRR, the risk factors were younger age, female, asthma, thyroid diseases, mental disorders, and a history of allergy and vasovagal reflex. CONCLUSION: In the mass vaccination settings, the Moderna vaccine can be used safely owing to the low incidence rates of IHSR and anaphylaxis. However, providers should be aware of the occurrence of ISRR. Although recipients with risk factors are associated with slightly increased risks of IHSR and ISRR, this is not of sufficient magnitude to warrant special measures regarding their vaccination.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , Anafilaxia , COVID-19 , Hipersensibilidade Imediata , Humanos , Vacina de mRNA-1273 contra 2019-nCoV/efeitos adversos , Anafilaxia/induzido quimicamente , Asma , Estudos de Casos e Controles , COVID-19/prevenção & controle , Hipersensibilidade Imediata/induzido quimicamente , Incidência , Fatores de Risco , Vacinação/efeitos adversos , Japão
12.
J Med Virol ; 83(4): 568-73, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21328369

RESUMO

The 2009 pandemic H1N1 influenza A virus spread quickly worldwide in 2009. Since most of the fatal cases were reported in developing countries, rapid and accurate diagnosis methods that are usable in poorly equipped laboratories are necessary. In this study, a mobile detection system for the 2009 H1N1 influenza A virus was developed using a reverse-transcriptase loop-mediated isothermal amplification (RT-LAMP) kit with a disposable pocket-warmer as a heating device (designated as pwRT-LAMP). The pwRT-LAMP can detect as few as 100 copies of the virus--which is nearly as sensitive as real-time reverse-transcription polymerase chain reaction (RT-PCR)--and does not cross-react with RNA of seasonal influenza viruses. To evaluate the usefulness of the pwRT-LAMP system, nasal swab samples were collected from 56 patients with flu-like symptoms and were tested. Real-time RT-PCR confirmed that the 2009 H1N1 influenza A virus was present in 27 of the 56 samples. Of these 27 positive samples, QuickVue Influenza A+B immunochromatography detected the virus in only 11 samples (11/27; 40.7%), whereas the pwRT-LAMP system detected the virus in 26 of the 56 samples (26/27 of the positive samples; 96.3%). These findings indicate that the mobile pwRT-LAMP system is an accurate diagnostic system for the 2009 H1N1 influenza A virus, and has great potential utility in diagnosing future influenza pandemics.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Virologia/métodos , Adulto , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
13.
J Chem Phys ; 134(20): 204313, 2011 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-21639446

RESUMO

We performed molecular dynamics (MD) simulations of nucleation from vapor at temperatures below the triple point for systems consisting of 10(4)-10(5) Lennard-Jones (L-J) type molecules in order to test nucleation theories at relatively low temperatures. Simulations are performed for a wide range of initial supersaturation ratio (S(0) ≃ 10-10(8)) and temperature (kT = 0.2-0.6ε), where ε and k are the depth of the L-J potential and the Boltzmann constant, respectively. Clusters are nucleated as supercooled liquid droplets because of their small size. Crystallization of the supercooled liquid nuclei is observed after their growth slows. The classical nucleation theory (CNT) significantly underestimates the nucleation rates (or the number density of critical clusters) in the low-T region. The semi-phenomenological (SP) model, which corrects the CNT prediction of the formation energy of clusters using the second virial coefficient of a vapor, reproduces the nucleation rate and the cluster size distributions with good accuracy in the low-T region, as well as in the higher-T cases considered in our previous study. The sticking probability of vapor molecules onto the clusters is also obtained in the present MD simulations. Using the obtained values of sticking probability in the SP model, we can further refine the accuracy of the SP model.

14.
Neurosci Lett ; 749: 135722, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592306

RESUMO

Much attention has been given to effects of repeated exposure to a shock wave as a possible factor causing severe higher brain dysfunction and post-traumatic stress disorder (PTSD)-like symptoms in patients with mild to moderate blast-induced traumatic brain injury (bTBI). However, it is unclear how the repeated exposure and the inter-exposure time affect the brain. In this study, we topically applied low-impulse (∼54 Pa·s) laser-induced shock waves (LISWs; peak pressure, ∼75.7 MPa) to the rat brain once or twice with the different inter-exposure times (15 min, 1 h, 3 h, 24 h and 7 days) and examined anxiety-related behavior and motor dysfunction in the rats as well as expression of ß-amyloid precursor protein (APP) as an axonal damage marker in the brains of the rats. The averaged APP expression scores for the rat brains doubly-exposed to LISWs with inter-exposure times from 15 min to 24 h were significantly higher than those for rats with a single exposure (P < 0.0001). The rats with double exposure to LISWs showed significantly more frequent anxiety-related behavior (P < 0.05) and poorer motor function (P < 0.01) than those of rats with a single exposure. When the inter-exposure time was extended to 7 days, however, the rats showed no significant differences either in axonal damage score or level of motor dysfunction. The results suggest that the cumulative effects of shock wave-related brain injury can be avoided with an appropriate inter-exposure time. However, clinical bTBI occurs in much more complex environments than those in our model. Further study considering other factors, such as the effects of acceleration, is needed to know the clinically-relevant, necessary inter-exposure time.


Assuntos
Axônios/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Traumatismos por Explosões/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Lasers , Animais , Ansiedade/fisiopatologia , Axônios/metabolismo , Traumatismos por Explosões/fisiopatologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Lasers/efeitos adversos , Ratos Sprague-Dawley , Transtornos de Estresse Pós-Traumáticos/fisiopatologia
15.
Toxicol Lett ; 350: 283-291, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34371142

RESUMO

Diethylenetriaminepentaacetate (DTPA) is the most widely used chelating agent for Pu and Am. Volunteers were assigned to receive intravenous injections or aerosol inhalations of 1 g of DTPA on days 1-4; volunteers received once daily injections of CaDTPA or ZnDTPA, CaDTPA inhalation as an aerosol, or CaDTPA injection on day 1 and ZnDTPA on days 2-4. CaDTPA injection or inhalation increased the excretion rates of Zn in urine with concomitantly reduced levels of serum Zn. Injection of CaDTPA reduced activities of serum alkaline phosphatase (AP) in parallel with the kinetics of Zn, whereas CaDTPA and ZnDTPA injection reduced activities of lactate dehydrogenase (LDH), and reduced activities of creatinine kinase (CK) were observed upon CaDTPA injection and its inhalation. Intravenous administration of CaDTPA and ZnDTPA enhanced excretion rates of Mn in urine, whereas transient reduction of Mn levels in serum was detected only via CaDTPA injection. Both CaDTPA and ZnDTPA transiently reduced levels of Mg in serum without affecting the excretion rates. On the other hand, both DTPAs increased excretion rates of toxic metals such as Pb and Cd, and CaDTPA also increased the rates of Hg. These results suggest that DTPA, and especially CaDTPA, removes essential metals and that the activities of these metalloenzymes are good indicators for the imbalance of essential metals during the DTPA administration. Our results also show that CaDTPA injection is more potent for removing these metals than ZnDTPA and inhalation of CaDTPA, and DTPA may be useful for the treatment of acute heavy metal poisoning with Pb, Cd, or Hg.


Assuntos
Quelantes/análise , Quelantes/farmacologia , Ácido Pentético/análise , Ácido Pentético/farmacocinética , Zinco/sangue , Zinco/urina , Administração por Inalação , Adulto , Aerossóis , Voluntários Saudáveis , Humanos , Injeções Intraperitoneais , Injeções Intravenosas , Japão , Masculino , Adulto Jovem
16.
Appl Opt ; 49(8): 1267-79, 2010 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-20220882

RESUMO

There are two widely accepted restrictions on the application of the discrete dipole approximation (DDA) in the study of light scattering by particles comparable to the wavelength: (1) when considering dielectric particles, the size of the cells must satisfy the condition kd|m|<0.5, where k is the wavenumber, d is the size of the cells, and m is the complex refractive index of the constituent material and (2) when considering conductive particles, the size of the cells must be small enough to reproduce sufficiently the evolution of the electromagnetic field in the skin layer. We examine both restrictions when the DDA is applied to irregularly shaped particles and show that its restrictions are not as strong as is widely accepted. For instance, when studying irregularly shaped particles averaged over orientations, even at kd|m|=1, the DDA provides highly accurate numerical results. Moreover, we show that the impact of using large constituent cells is similar to that produced by surface roughness; therefore, the replacement of the target particle by an array of large constituent cells has the same effect, qualitatively, as incorporating additional small-scale surface roughness on the particle. Such a modification of the target particle can be desirable in many practical applications of DDA when irregularly shaped particles are considered. When applying DDA to conductive, nonspherical particles, the insufficient description of the electromagnetic field in the skin layer does not lead to a violation of the Maxwell equations, although it has a visible but nonmajor influence on the light-scattering properties of the target.

17.
Nihon Jibiinkoka Gakkai Kaiho ; 113(8): 661-9, 2010 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-20845708

RESUMO

BACKGROUND: Persons allergic to birch pollen often report oral and pharyngeal hypersensitivity to fruit and vegetables, such as apples and peaches due to immunological cross-reactivity, or oral allergy syndrome (OAS) sometimes accompanied by systemic reaction. Such cross-reactive antigen reactions involve Bet v 1, the main birch-pollen allergen, and Bet v 2, birch-pollen profilin. We evaluated the food/antigen relationship. METHODS: Subjects interviewed numbered 60-40 women and 20 men aged 12 to 70 (mean age: 35 years)-suffering OAS episodes and having IgE birch-pollen antibodies. Using CAP scoring we examined IgE antibodies to recombinant Bet v 1 (rBet v 1), recombinant Bet v 2 (rBet v 2), and recombinant Pru p 3 (rPru p 3) a peach lipid transfer protein (LTP). A CAP score of 0.35 or more was considered positive. We evaluated the relationship between recombinant allergens and 9 fruit often involving OAS--apple, peach, cherry, kiwi, pear, melon, plum, strawberry, and watermelon-based on subjects' reports. RESULTS: Of the 60, all (100%) were rBet v 1-positive, 9 (15%) rBet v 2-positive, and none (0%) rPru p 3-positive. Rose-family fruit-apples, peaches, cherries, pears, plums, and strawberries-often caused OAS regardless of positive or negative rBet v 2 CAP and were associated with rBet v 1. In contrast, more of those who were rBet v 2 CAP-positive had OAS to non-rose-family fruit-melon and watermelon-than those rBet v 2-negative. In rose-family and non-rose-family classification of the 9 fruit, cluster analysis and kappa statistics showed non-rose-family melon, watermelon, and kiwi to be associated with rBet v 2, as were grass and mugwort pollen allergies. CONCLUSION: Bet v 1 is associated with OAS due to rose-family fruit and Bet v 2 with OAS due to non-rose-family fruit.


Assuntos
Anticorpos/análise , Antígenos de Plantas/imunologia , Betula/imunologia , Criança , Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/análise , Rinite Alérgica Sazonal/imunologia , Adolescente , Adulto , Idoso , Apraxias , Reações Cruzadas , Feminino , Frutas/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Verduras/imunologia
18.
Hepatogastroenterology ; 56(93): 1100-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19760950

RESUMO

BACKGROUND/AIMS: Recent studies have shown that blocking of angiotensin-II signaling can attenuate liver fibrosis in various experimental models. The aim of this study was to examine the clinical effect of an angiotensin-II type-1 receptor blocker, candesartan, on the progression of hepatic fibrosis in chronic hepatitis C patients. METHODOLOGY: Twelve chronic hepatitis C patients with hypertension enrolled as candesartan-treated patients and followed up prospectively, were compared with age- and sex-matched 20 chronic hepatitis C patients with no candesartan treatment. We evaluated alterations in hepatic fibrosis grades with these noninvasive fibrotic indexes: Forns index, the AST to platelet ratio index (APRI) and FibroIndex, every 3 months. RESULTS: There were initially no significant differences between the candesartan-treated and control groups in clinical characteristics. Candesartan treatment induced a significant improvement in Forns Index, APRI and FibroIndex during treatment in comparison with the control group. There were no severe side effects in the candesartan group. CONCLUSIONS: These results suggest that candesartan in regular doses has an anti-fibrotic effect on patients with chronic hepatitis C.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Benzimidazóis/farmacologia , Hepatite C Crônica/complicações , Cirrose Hepática/tratamento farmacológico , Tetrazóis/farmacologia , Idoso , Análise de Variância , Compostos de Bifenilo , Feminino , Humanos , Cirrose Hepática/etiologia , Masculino , Estudos Prospectivos , Resultado do Tratamento
19.
Arerugi ; 58(2): 133-9, 2009 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-19329876

RESUMO

PURPOSE: Evaluation of the relationships between foods and pollen allergens in oral allergy syndrome (OAS). METHODS: Serous level of specific IgE against recombinant peach allergens (rPru p 1, rPru p 3 and rPru p 4) in 17 peach OAS patients were examined by Pharmacia CAP RASTsystem. RESULTS: In 17 pollinosis patients, the number of patients positive to peach, rPru p 1, rPru p 4 and rPru p 3 RAST were 13 (76%), 14 (82%), 6 (35%) and 0 (0%), respectively. The RAST value of rPru p 1 was significantly correlated with that of natural birch pollen extract (r=0.745, p=0.0003), but not with that of mugwort pollen extract. The RAST value of rPru p 4 was significantly correlated with that of mugwort pollen extract (r=0.602, p=0.0092), but not with that of natural birch pollen extract. CONCLUSION: Concerning to peach OAS, the most important cross-reactive antigen is Pru p 1 in birch pollinosis, and is Pru p 4 in mugwort pollinosis.


Assuntos
Antígenos de Plantas/imunologia , Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/sangue , Pólen/imunologia , Prunus/imunologia , Rinite Alérgica Sazonal/imunologia , Reações Cruzadas , Proteínas Recombinantes/imunologia
20.
Drug Res (Stuttg) ; 69(11): 583-597, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31390663

RESUMO

In the case of nuclear incidents, radioiodine may be liberated. After incorporation it accumulates in the thyroid and by internal irradiation enhances the risk of cancer occurrence. By administering a large dose of non-radioactive iodine the uptake of radioiodine into the gland can be inhibited ("iodine blockade"). Biokinetic models using first order kinetics are not suited to simulate iodine blockade, as the uptake into the gland is mediated by a saturable active transport. Therefore, we integrated an uptake mechanism described by a Michaelis-Menten kinetic into a simple ICRP biokinetic model. We moreover added a total uptake blocking mechanism representing the Wolff-Chaikoff effect becoming active when the gland is saturated with iodine. The validity of the model was ascertained by comparison with IMBA software. The competition of radioiodine and stable iodine at the membrane carrier site was modeled according to the rate law for monomolecular reactions for competing substrates. Our simulations show that competition for the uptake at the membrane carrier site accounts for about 60% and the saturation of the gland with iodine for over 35% of the total protective efficacy that exceeds 95%. Following acute radioiodine exposure, it is preferable to administer a single large dose of stable iodine. In the case of continuous radioiodine exposure, a single dose of stable iodine is less effective than after an acute exposure and splitting the total available dose and shortening the dosage intervals enhance efficacy. Model-based simulations may be a useful tool to develop antidote dosage schemes for uncommon emergencies.


Assuntos
Antídotos/uso terapêutico , Radioisótopos do Iodo/efeitos adversos , Iodo/efeitos adversos , Humanos , Cinética , Modelos Biológicos , Radiometria/métodos , Glândula Tireoide/efeitos dos fármacos
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