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1.
Earth Planets Space ; 72(1): 111, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32831576

RESUMO

We investigate the longitudinal structure of the oxygen torus in the inner magnetosphere for a specific event found on 12 September 2017, using simultaneous observations from the Van Allen Probe B and Arase satellites. It is found that Probe B observed a clear enhancement in the average plasma mass (M) up to 3-4 amu at L = 3.3-3.6 and magnetic local time (MLT) = 9.0 h. In the afternoon sector at MLT ~ 16.0 h, both Probe B and Arase found no clear enhancements in M. This result suggests that the oxygen torus does not extend over all MLT but is skewed toward the dawn. Since a similar result has been reported for another event of the oxygen torus in a previous study, a crescent-shaped torus or a pinched torus centered around dawn may be a general feature of the O+ density enhancement in the inner magnetosphere. We newly find that an electromagnetic ion cyclotron (EMIC) wave in the H+ band appeared coincidently with the oxygen torus. From the lower cutoff frequency of the EMIC wave, the ion composition of the oxygen torus is estimated to be 80.6% H+, 3.4% He+, and 16.0% O+. According to the linearized dispersion relation for EMIC waves, both He+ and O+ ions inhibit EMIC wave growth and the stabilizing effect is stronger for He+ than O+. Therefore, when the H+ fraction or M is constant, the denser O+ ions are naturally accompanied by the more tenuous He+ ions, resulting in a weaker stabilizing effect (i.e., larger growth rate). From the Probe B observations, we find that the growth rate becomes larger in the oxygen torus than in the adjacent regions in the plasma trough and the plasmasphere.

2.
Space Sci Rev ; 218(5): 38, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757012

RESUMO

This paper presents the highlights of joint observations of the inner magnetosphere by the Arase spacecraft, the Van Allen Probes spacecraft, and ground-based experiments integrated into spacecraft programs. The concurrent operation of the two missions in 2017-2019 facilitated the separation of the spatial and temporal structures of dynamic phenomena occurring in the inner magnetosphere. Because the orbital inclination angle of Arase is larger than that of Van Allen Probes, Arase collected observations at higher L -shells up to L ∼ 10 . After March 2017, similar variations in plasma and waves were detected by Van Allen Probes and Arase. We describe plasma wave observations at longitudinally separated locations in space and geomagnetically-conjugate locations in space and on the ground. The results of instrument intercalibrations between the two missions are also presented. Arase continued its normal operation after the scientific operation of Van Allen Probes completed in October 2019. The combined Van Allen Probes (2012-2019) and Arase (2017-present) observations will cover a full solar cycle. This will be the first comprehensive long-term observation of the inner magnetosphere and radiation belts.

3.
Sci Rep ; 11(1): 13724, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257336

RESUMO

Pulsating aurorae (PsA) are caused by the intermittent precipitations of magnetospheric electrons (energies of a few keV to a few tens of keV) through wave-particle interactions, thereby depositing most of their energy at altitudes ~ 100 km. However, the maximum energy of precipitated electrons and its impacts on the atmosphere are unknown. Herein, we report unique observations by the European Incoherent Scatter (EISCAT) radar showing electron precipitations ranging from a few hundred keV to a few MeV during a PsA associated with a weak geomagnetic storm. Simultaneously, the Arase spacecraft has observed intense whistler-mode chorus waves at the conjugate location along magnetic field lines. A computer simulation based on the EISCAT observations shows immediate catalytic ozone depletion at the mesospheric altitudes. Since PsA occurs frequently, often in daily basis, and extends its impact over large MLT areas, we anticipate that the PsA possesses a significant forcing to the mesospheric ozone chemistry in high latitudes through high energy electron precipitations. Therefore, the generation of PsA results in the depletion of mesospheric ozone through high-energy electron precipitations caused by whistler-mode chorus waves, which are similar to the well-known effect due to solar energetic protons triggered by solar flares.

4.
Sci Rep ; 10(1): 3380, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32098993

RESUMO

The brightness of aurorae in Earth's polar region often beats with periods ranging from sub-second to a few tens of a second. Past observations showed that the beat of the aurora is composed of a superposition of two independent periodicities that co-exist hierarchically. However, the origin of such multiple time-scale beats in aurora remains poorly understood due to a lack of measurements with sufficiently high temporal resolution. By coordinating experiments using ultrafast auroral imagers deployed in the Arctic with the newly-launched magnetospheric satellite Arase, we succeeded in identifying an excellent agreement between the beats in aurorae and intensity modulations of natural electromagnetic waves in space called "chorus". In particular, sub-second scintillations of aurorae are precisely controlled by fine-scale chirping rhythms in chorus. The observation of this striking correlation demonstrates that resonant interaction between energetic electrons and chorus waves in magnetospheres orchestrates the complex behavior of aurora on Earth and other magnetized planets.

5.
J Investig Allergol Clin Immunol ; 18(3): 194-201, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18564631

RESUMO

OBJECTIVE: To establish the relationship between the use of acetaminophen and the frequency of asthma in Mexican children in 3 Mexican cities. METHODS: Ours was a multicenter, observational, descriptive, cross-sectional study. Patients from 6 to 7 years of age participating in Phase Three B of the ISAAC (International Study of Asthma and Allergies in Children) living in the north of Mexico City, Victoria City, and Merida were included. After adjusting for confounders, we calculated the odds ratios (OR) for the presence of wheezing ever, wheezing in the last 12 months, asthma ever, and the use of acetaminophen in the first year of life and during the last 12 months. RESULTS: The ORs for wheezing ever, wheezing in the last year, and asthma ever with respect to use of acetaminophen in the first year of life were not statistically significant (P > .05) in Mexico City, but they were significant in Victoria City (P < .05) and Merida (P < .05). The ORs (95% confidence intervals) for wheezing ever, wheezing in the last year, and asthma ever with respect to use of acetaminophen in the last year were 3.44 (2.96-4.0), 7.97 (5.89-10.78), and 6.10 (3.30-8.81) (P < .05) in Mexico City. Values forVictoria City were 1.36 (1.13-1.63), 3.80 (2.88-5.05), and 2.18(1.57-3.01) (P < .05). Those for Merida were 1.61 (1.40-1.85), 2.07 (1.73-2.48), and 1.53 (1.29-1.82) (P < .05). CONCLUSION: The use of acetaminophen is associated with the presence of wheezing and asthma in 3 different cities in Mexico.


Assuntos
Acetaminofen/uso terapêutico , Asma/epidemiologia , Criança , Estudos Transversais , Feminino , Humanos , Masculino , México/epidemiologia , Saúde da População Urbana
6.
Structure ; 5(1): 81-94, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9016714

RESUMO

BACKGROUND: Several strains of yeasts and fungi produce proteinous substances, termed killer toxins, which kill sensitive strains. The SMK toxin, secreted by the halotolerant yeast Pichia farinosa KK1 strain, uniquely exhibits its maximum killer activity under conditions of acidic pH and high salt concentration. The toxin is composed of two distinct subunits, alpha and beta, which tightly interact with each other under acidic conditions. However, they are easily dissociated under neutral conditions and lose the killer activity. The three-dimensional structure of the SMK toxin will provide a better understanding of the mechanism of toxicity of this protein and the cause of its unique pH-dependent stability. RESULTS: Two crystal structures of the SMK toxin have been determined at 1.8 A resolution in different ionic strength conditions. The two subunits, alpha and beta, are jointly folded into an ellipsoidal, single domain structure belonging to the alpha/beta-sandwich family. The folding topology of the SMK toxin is essentially the same as that of the fungal killer toxin, KP4. This shared topology contains two left-handed split betaalphabeta motifs, which are rare in the other proteins. Many acidic residues are clustered at the bottom of the SMK toxin molecule. Some of the carboxyl sidechains interact with each other through hydrogen bonds. The ionic strength difference induces no evident structural change of the SMK toxin except that, in the high ionic strength crystal, a number of sulfate ions are electrostatically bound near the basic residues which are also locally distributed at the bottom of the toxin molecule. CONCLUSIONS: The two killer toxins, SMK and KP4, share a unique folding topology which contains a rare structural motif. This observation may suggest that these toxins are evolutionally and/or functionally related. The pH-dependent stability of the SMK toxin is a result of the intensive interactions between the carboxyl groups. This finding is important for protein engineering, for instance, towards stabilization of the toxin molecule in a broader pH range. The present crystallographic study revealed that the structure of the SMK toxin itself is hardly affected by the ionic strength, implying that a high salt concentration affects the sensitivity of the cell against the toxin.


Assuntos
Micotoxinas/química , Pichia/química , Dobramento de Proteína , Sequência de Aminoácidos , Cristalização , Cristalografia por Raios X , Dimerização , Proteínas Fúngicas/química , Ligação de Hidrogênio , Fatores Matadores de Levedura , Modelos Moleculares , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional/fisiologia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Alinhamento de Sequência , Proteínas Virais/química
7.
J Am Soc Mass Spectrom ; 11(1): 54-61, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10631664

RESUMO

Electrospray ionization mass spectrometry (ESI-MS) was applied to the analysis of the dissociation and denaturation processes of a heterodimeric yeast killer toxin SMKT. The two distinct subunits of SMKT noncovalently associate under acidic conditions, but become dissociated and denatured under neutral and basic conditions. In order to understand the unique pH-dependent denaturation mechanism of this protein, a pH titration was performed by utilizing ESI-MS. The molecular ions of the heterodimer which possesses the highly ordered structure, were mainly observed below pH 4.6. However, the two subunits immediately dissociated at this pH. The spectra measured with various settings of the mass spectrometer indirectly demonstrated that the pH-dependent dissociation occurs in the liquid phase. The current result as well as the three-dimensional structure of SMKT suggest that the deprotonation of a specific carboxyl group triggers a cooperative dissociation process of this protein. In conclusion, the pH titration of a protein by ESI-MS is particularly effective, when the unfolding process or the biological function of the protein is related to the interaction with other molecules.


Assuntos
Proteínas Fúngicas/química , Micotoxinas/química , Concentração de Íons de Hidrogênio , Fatores Matadores de Levedura , Espectrometria de Massas , Desnaturação Proteica
8.
Bioresour Technol ; 95(1): 41-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15207293

RESUMO

Biomass slurry fuel (BSF) production has recently been developed as a natural energy for the conversion of solid biomass into fuel. In addition to using fuel, filtrates from BSF production may also serve a chemical source with several organic compounds. There is an increasing interest in the research and application of biomass-based filtrates. In this study, fungicidal and termiticidal properties of filtrates from BSF production using sugi (Cryptomeria japonica) and acacia (Acacia mangium) wood were evaluated in laboratory decay and termite resistance tests. Wood blocks treated with the filtrates showed increased resistance against brown-rot fungus, Fomitopsis palustris. However the filtrates from sugi wood processed at 270 degrees C which contained less phenolic compounds than the other filtrates were effective against white-rot fungus, Trametes versicolor. Phenolic compounds of filtrates seemed to play a role in the decay resistance tests however the filtrates did not increase the durability of the wood blocks against subterranean termites Coptotermes formosanus. Despite high acetic and lactic acid content of the filtrates, vanillin content of the filtrates may have served as an additional food source and promoted termite attack. It can be concluded that filtrates with phenolic compounds from lignin degradation during BSF production can be considered for targeted inhibition of brown-rot.


Assuntos
Fontes de Energia Bioelétrica , Fontes Geradoras de Energia , Fungicidas Industriais/farmacologia , Inseticidas/farmacologia , Resíduos , Animais , Biomassa , Filtração , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Isópteros/efeitos dos fármacos , Eliminação de Resíduos Líquidos , Madeira
9.
Int J Med Inform ; 51(1): 59-68, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9749900

RESUMO

To realize clinical data exchange between healthcare providers, there must be many standards in many layers. Terms and codes should be standardized, syntax to wrap the data must be mutually parsable, then transfer protocol or exchange media should be agreed. Among many standards for the syntax, HL7 and DICOM are most successful. However, everything could not be handled by HL7 solely. DICOM is good for radiology images, but, other clinical images are already handled by other 'lighter' data formats like JPEG, TIFF. So, it is not realistic to use only one standard for every area of clinical information. For description of medical records, especially for narrative information, an standard generalized mark-up language, document type definition (SGML DTD) for medical information, called MML (medical markup language) had been created in Japan. It is already implemented in more than ten healthcare providers. However, it is again not realistic to use MML solely for clinical information in various level of detail. Therefore, we proposed a guideline for use of available medical standards to facilitate clinical information exchange between healthcare providers. It is called MERIT-9 (Medical Records, Images, Texts, -Information Exchange). A typical use is HL7 messages, DICOM files, referred from an MML file in a patient record, as external entities. Both MML and MERIT-9 have been research projects of Japanese Ministry of Health and Welfare and the purpose is to facilitate clinical data exchanges. They are becoming to be used in technical specifications for new hospital information systems in Japan.


Assuntos
Diagnóstico por Imagem/normas , Sistemas de Informação Hospitalar/normas , Informática Médica/normas , Sistemas Computadorizados de Registros Médicos/normas , Redes Comunitárias , Guias como Assunto , Humanos , Japão , Software
10.
Hinyokika Kiyo ; 47(12): 873-6, 2001 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-11828777

RESUMO

A 68-year-old woman presented with urinary pain and frequency. Cystoscopy, intravenous pyelography and magnetic resonance imaging showed a huge bladder mass and hydronephrosis of the left kidney. Transurethral resection of bladder tumor (TUR-Bt) was done. Histopathological findings of TUR-biopsy was high grade transitional cell carcinoma. Post operatively, the laboratory examination showed marked leukocytosis with a maximum of 99,600/mm3 in the peripheral blood and a high level of granulocyte colony stimulating factor (G-CSF), 70 pg/ml in the serum (normal: less than 9.8 pg/ml). Serum calcium level increased gradually and parathyroid hormone-related protein (PTH-rP) revealed high, 8.4 pMol/l (normal: less than 0.6 pMol/l). The tumor cells were positive for G-CSF and PTH-rP immunohistochemical staining. She died of the disease 46 days after the operation. This is the third case of G-CSF and PTH-rP producing bladder tumor in the literature.


Assuntos
Carcinoma de Células de Transição/metabolismo , Fator Estimulador de Colônias de Granulócitos/biossíntese , Proteína Relacionada ao Hormônio Paratireóideo , Hormônio Paratireóideo/biossíntese , Fragmentos de Peptídeos/biossíntese , Proteínas , Neoplasias da Bexiga Urinária/metabolismo , Idoso , Feminino , Humanos , Imuno-Histoquímica
11.
Hinyokika Kiyo ; 40(9): 829-32, 1994 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-7801846

RESUMO

A 71-year-old female presented with left back pain at our hospital. She had had the same symptom about 1 year previously, but she had been presumed to have undergone stone passage because her symptom had disappeared. At this time a urogram, either excretory or retrograde, showed narrowing of each caliceal infundibulum and dilatation of each calyx in the left kidney, but otherwise normal findings. A cytology of left ureteral urine was class V, and cystoscopy revealed no abnormality. Under the diagnosis of left renal pelvic tumor she underwent nephroureterectomy with resection of a bladder cuff and retroperitoneal lymphadenectomy. The resected specimen had no gross tumor throughout the renal pelvis and ureter, but histological examination revealed transitional cell carcinoma in situ (grade 2) in most of the renal pelvis and infiltration of inflammatory cells in the submucosa. The ureter did not have any cancerous lesion, and no lymph node metastases was found. Four months postoperatively she is thought to have no evidence of disease with negative urinary cytology.


Assuntos
Carcinoma in Situ/diagnóstico , Carcinoma de Células de Transição/diagnóstico , Neoplasias Renais/diagnóstico , Idoso , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/cirurgia , Feminino , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Pelve Renal
12.
Hinyokika Kiyo ; 44(11): 813-6, 1998 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-9893228

RESUMO

We describe a case of bilateral renal cell carcinoma associated with chronic renal failure. A 49-year-old man was admitted to our hospital to initiate hemodialysis. He was found to have multiple renal cystic changes and a left renal mass by ultrasound. Computed tomographic (CT) scan showed a tumor 4 cm in diameter in the left kidney and another one 2 cm in diameter in the right kidney. Left nephrectomy was first performed and histopathological examination revealed renal cell carcinoma of mixed type and granular subtype. Six months after the operation, CT scan showed the mild growth of the tumor in the right kidney. Right nephrectomy was performed and histopathological examination revealed renal cell carcinoma of papillary type and granular subtype. The patient remains well on hemodialysis, with no evidence of recurrence or metastasis for 13 months after nephrectomy.


Assuntos
Carcinoma de Células Renais/etiologia , Falência Renal Crônica/complicações , Neoplasias Renais/etiologia , Neoplasias Primárias Múltiplas , Carcinoma de Células Renais/patologia , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia
13.
Hinyokika Kiyo ; 40(3): 229-32, 1994 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-8178740

RESUMO

A 70-year-old woman underwent a left radical nephrectomy. The pathological examination revealed renal cell carcinoma (RCC), grade 1 and no lymph node metastasis. She suffered a recurrence in the renal fossa 11 years after the operation. The doubling time of the recurrent lesion was calculated to be very long for the cancer; about 1.3 years. Another case was in a 61-year-old woman, who underwent a right radical nephrectomy. The pathological examination revealed RCC, grade 1 with vascular invasion and no lymph node metastasis. Eleven years postoperatively she developed metastases in both lungs. The other case was in a 39-year-old woman, who underwent right radical nephrectomy. The pathological examination revealed RCC, grade 1 with vascular invasion and no lymph node metastasis. Eight years postoperatively she developed a recurrence in the left kidney. The doubling time of the recurrent lesion was about 0.9 year. All three patients responded to conservative therapy including interferon. Taking those doubling times into account, the recurrent lesions in the first and third cases seemed to have been growing very slowly and not rapidly immediately before clinically evident recurrence. Patients with a low grade RCC must have life-long followup.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Neoplasias Renais/cirurgia , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Nefrectomia
14.
Hinyokika Kiyo ; 47(1): 5-10, 2001 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-11235223

RESUMO

There has been much controversy regarding radical surgery for both localized and locally extensive carcinoma of the prostate. We analyzed the outcome of radical prostatectomy and the preoperative evaluation in order to assess the indication of radical prostatectomy. Fifty-six patients with clinical stage B or C prostate cancer were treated by radical prostatectomy without neoadjuvant therapy. Endocrine therapy was added to the non-curative cases postoperatively. Preoperative evaluation was compared with pathological results and survival, and furthermore the usefulness of the preoperative PSA and PSA half-life were investigated. The mean follow-up period was 44.5 months. The accuracy of the grade and the clinical stage were 58.9% and 23.2%, respectively. Organ-confined disease was seen in patients with an initial PSA level less than 30 ng/ml. Postoperative PSA half-life is significantly prolonged in cases with poorly differentiated adenocarcinoma or lymph node involvement and may be a predictor of PSA failure. The cause-specific 5-year survival rates were 92.7% on the whole, 92.9% for well differentiated, 96.7% for moderately differentiated, 85.7% for poorly differentiated, 100% for stage B1, 95.0% for stage B2 and 86.8% for stage C. These results indicated that patients with an initial PSA level of less than 30 ng/ml will benefit from radical prostatectomy.


Assuntos
Prostatectomia , Neoplasias da Próstata/cirurgia , Idoso , Biomarcadores Tumorais/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia
15.
Nihon Hinyokika Gakkai Zasshi ; 85(12): 1773-6, 1994 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-7869652

RESUMO

A case of multilocular cystic renal cell carcinoma was reported. The patient was 69-year-old male who had been examined for postoperative study of gastric cancer by abdominal CT. The abdominal CT incidentally revealed right adrenal tumor which was non-functional and multilocular cysts in the lower pole of the right kidney. Selective renal arteriography showed a hypovascular mass with fine neovascularity. These two findings of CT and arteriography were though to represent a probable malignant tumor but renal function of the patient decreased moderately. Surgical exploration was done and right renal masses were thought to be seen benign multilocular cysts without capsule. Simple excision of the wall of cysts and right adrenalectomy were performed. Pathological examinations showed multilocular cystic renal cell carcinoma and benign adrenal hyperplasia. Additionally partial nephrectomy was done. Surgical margin of the kidney was tumor free and postoperative course was uneventful. Prognosis of multiocular cystic renal cell carcinoma is good, therefore conservative surgery is recommended.


Assuntos
Glândulas Suprarrenais/patologia , Carcinoma de Células Renais/cirurgia , Doenças Renais Císticas/cirurgia , Neoplasias Renais/cirurgia , Nefrectomia , Idoso , Carcinoma de Células Renais/complicações , Humanos , Hiperplasia/complicações , Doenças Renais Císticas/complicações , Neoplasias Renais/complicações , Masculino
16.
Science ; 345(6204): 1581-4, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25258073

RESUMO

Jupiter's magnetosphere is a strong particle accelerator that contains ultrarelativistic electrons in its inner part. They are thought to be accelerated by whistler-mode waves excited by anisotropic hot electrons (>10 kiloelectron volts) injected from the outer magnetosphere. However, electron transportation in the inner magnetosphere is not well understood. By analyzing the extreme ultraviolet line emission from the inner magnetosphere, we show evidence for global inward transport of flux tubes containing hot plasma. High-spectral-resolution scanning observations of the Io plasma torus in the inner magnetosphere enable us to generate radial profiles of the hot electron fraction. It gradually decreases with decreasing radial distance, despite the short collisional time scale that should thermalize them rapidly. This indicates a fast and continuous resupply of hot electrons responsible for exciting the whistler-mode waves.

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