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2.
Science ; 372(6543): 742-745, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33986180

RESUMO

Half of the chemical elements heavier than iron are produced by the rapid neutron capture process (r-process). The sites and yields of this process are disputed, with candidates including some types of supernovae (SNe) and mergers of neutron stars. We search for two isotopic signatures in a sample of Pacific Ocean crust-iron-60 (60Fe) (half-life, 2.6 million years), which is predominantly produced in massive stars and ejected in supernova explosions, and plutonium-244 (244Pu) (half-life, 80.6 million years), which is produced solely in r-process events. We detect two distinct influxes of 60Fe to Earth in the last 10 million years and accompanying lower quantities of 244Pu. The 244Pu/60Fe influx ratios are similar for both events. The 244Pu influx is lower than expected if SNe dominate r-process nucleosynthesis, which implies some contribution from other sources.

3.
Plant Biol (Stuttg) ; 23(5): 874-877, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33915009

RESUMO

After the nuclear accident in Fukushima Prefecture, Japan, in 2011, 137 Caesium (Cs) contaminated nearby agricultural regions. Studies in these rice fields found that low K and high N fertilizer application enhanced Cs uptake in rice shoots. However, the influence of root and soil physics on these findings, as well as precise nutrient levels, remain to be clarified. We sought to analyse these relationships utilizing hydroponically grown rice plants. The rice plants were subjected to various concentrations of K and N nutrient solutions. We measured Cs allocation within the plants and performed transcript analyses using root tissues. Under low-K conditions, low-N plants accumulated less Cs in shoots and more in roots when compared to control-N conditions, even though overall Cs uptake remained unchanged. Expression analyses of root mRNAs showed that low-N plants accumulated reduced levels of OsAKT1 mRNA, encoding a K transporter. We also found a negative relationship between shoot Cs and K status in control-N but not in low-N conditions. Our results suggest that the application of N shifts Cs from roots into the shoots and that OsAKT1 in root vascular tissues influences Cs allocation. In practice, fine tuning N/K application and targeted breeding of K transporters might mitigate Cs contamination in rice plants.


Assuntos
Oryza , Césio , Radioisótopos de Césio , Nitrogênio , Melhoramento Vegetal , Raízes de Plantas
4.
Epidemiol Infect ; 148: e250, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33046159

RESUMO

We analysed associations between exposure to nightlife businesses and severe acute respiratory syndrome coronavirus 2 PCR test results at a tertiary hospital in Tokyo between March and April 2020. A nightlife group was defined as those who had worked at or visited the businesses. We included 1517 individuals; 196 (12.9%) were categorised as the nightlife group. After propensity score matching, the proportion of positive PCR tests in the nightlife group was significantly higher than that in the non-nightlife group (nightlife, 63.8%; non-nightlife, 23.0%; P < 0.001). An inclusive approach to mitigate risks related to the businesses needs to be identified.


Assuntos
Betacoronavirus , Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Adulto , COVID-19 , Comércio , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Tóquio/epidemiologia
5.
Clin Exp Immunol ; 200(3): 302-309, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155293

RESUMO

Stroke can be a cause of death, while in non-fatal cases it is a common cause of various disabilities resulting from associated brain damage. However, whether a specific periodontal pathogen is associated with increased risk of unfavorable outcome after stroke remains unknown. We examined risk factors for unfavorable outcome following stroke occurrence, including serum antibody titers to periodontal pathogens. The enrolled cohort included 534 patients who had experienced an acute stroke, who were divided into favorable (n = 337) and unfavorable (n = 197) outcome groups according to modified ranking scale (mRS) score determined at 3 months after onset (favorable = score 0 or 1; unfavorable = score 2-6). The associations of risk factors with unfavorable outcome, including serum titers of IgG antibodies to 16 periodontal pathogens, were examined. Logistic regression analysis showed that the initial National Institutes of Health stroke scale score [odds ratio (OR) = 1·24, 95% confidence interval (CI) = 1·18-1·31, P < 0·001] and C-reactive protein (OR = 1·29, 95% CI = 1·10-1·51, P = 0·002) were independently associated with unfavorable outcome after stroke. Following adjustment with those, detection of the antibody for Fusobacterium nucleatum ATCC 10953 in serum remained an independent predictor of unfavorable outcome (OR = 3·12, 95% CI = 1·55-6·29, P = 0·002). Determination of the antibody titer to F. nucleatum ATCC 10953 in serum may be useful as a predictor of unfavorable outcome after stroke.


Assuntos
Anticorpos Antibacterianos/sangue , Fusobacterium nucleatum/metabolismo , Imunoglobulina G/sangue , Acidente Vascular Cerebral/sangue , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/imunologia , Feminino , Fusobacterium nucleatum/imunologia , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Acidente Vascular Cerebral/imunologia
6.
Nature ; 532(7597): 69-72, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27078565

RESUMO

The rate of supernovae in our local Galactic neighbourhood within a distance of about 100 parsecs from Earth is estimated to be one every 2-4 million years, based on the total rate in the Milky Way (2.0 ± 0.7 per century). Recent massive-star and supernova activity in Earth's vicinity may be traced by radionuclides with half-lives of up to 100 million years, if trapped in interstellar dust grains that penetrate the Solar System. One such radionuclide is (60)Fe (with a half-life of 2.6 million years), which is ejected in supernova explosions and winds from massive stars. Here we report that the (60)Fe signal observed previously in deep-sea crusts is global, extended in time and of interstellar origin from multiple events. We analysed deep-sea archives from all major oceans for (60)Fe deposition via the accretion of interstellar dust particles. Our results reveal (60)Fe interstellar influxes onto Earth at 1.5-3.2 million years ago and at 6.5-8.7 million years ago. The signal measured implies that a few per cent of fresh (60)Fe was captured in dust and deposited on Earth. Our findings indicate multiple supernova and massive-star events during the last ten million years at distances of up to 100 parsecs.

7.
Transplant Proc ; 45(7): 2825-30, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24034059

RESUMO

Metastatic pulmonary calcification, defined as calcium deposition in the intact lung, is commonly seen in patients with chronic renal failure, and it is known to be a benign clinical condition when detected by chance in an asymptomatic patient. Here we report the case of a 33-year-old woman who developed rapid and aggressive metastatic pulmonary calcification shortly after a living donor kidney transplantation, which induced acute antibody-mediated rejection. The patient's metastatic pulmonary calcification was successfully improved by extensive treatment for graft rejection, the correction of her accompanying primary hyperparathyroidism, and medical treatment with a bisphosphonate and sodium thiosulfate. Aggressive pulmonary calcification is reported as a rare complication seen in patients who have undergone a failed renal transplantation. A failed renal graft and accompanying secondary hyperparathyroidism seem to accelerate metastatic calcification. Most of the patients who develop aggressive pulmonary calcification suffer from the rapid progression of dyspnea and occasionally fever, and they die of respiratory failure. Pulmonary calcification should be considered in a patient developing dyspnea and unexplained pulmonary infiltrate, especially in the context of renal graft rejection; otherwise the prognosis of the patient will be very poor.


Assuntos
Calcinose , Hiperparatireoidismo Primário/cirurgia , Transplante de Rim/efeitos adversos , Doadores Vivos , Pulmão/patologia , Adulto , Calcinose/diagnóstico por imagem , Feminino , Humanos , Hiperparatireoidismo Primário/patologia , Insuficiência Renal/cirurgia , Tomografia Computadorizada por Raios X
8.
J Periodontal Res ; 48(5): 606-14, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23360525

RESUMO

BACKGROUND AND OBJECTIVE: Endopeptidases, such as neutral endopeptidase (NEP), endothelin-converting enzyme-1 (ECE-1) and a disintegrin and metalloprotease 17 (ADAM17), are believed to have various important roles in oral mucosal and epidermal tissue for the regulation of defensive biological responses in the oral cavity, and their expression and activity are influenced by various factors, including oral diseases. However, knowledge concerning these endopeptidases in the oral cavity has been minimal until now. This study focused on three metalloendopeptidases - NEP, ECE-1 and ADAM17 - in the oral buccal mucosal epithelium of patients with periodontal diseases and investigated the relationship between their gene-expression levels and periodontal disease. MATERIAL AND METHODS: The levels of expression of NEP, ECE-1 and ADAM17 mRNAs in tissue samples collected from the oral buccal mucosal epithelium of 61 patients were investigated by relative quantification using real-time RT-PCR analysis. information on oral and systemic health was obtained from the clinical record of each patient. RESULTS: Among the three groups, classified based on the diagnosis of periodontal diseases (healthy/gingivitis, early periodontitis and moderate/advanced periodontitis), the relative expression level of NEP mRNA was significantly increased in the early periodontitis group and in the moderate/advanced periodontitis group compared with that in the healthy/gingivitis group. Moreover, the relative expression levels of ECE1 and ADAM17 mRNAs were significantly increased in the moderate/advanced periodontitis group compared with those in the healthy/gingivitis group. The correlation coefficients between the mean relative expression levels of NEP and ECE1 mRNAs, NEP and ADAM17 mRNAs, and ECE1 and ADAM17 mRNAs were r = 0.758, r = 0.707 and r = 0.934, respectively (p < 0.001). Furthermore, among the oral-related factors, there was a significant correlation between the number of sites with probing pocket depths of more than 4 mm and of more than 6 mm and the relative expression levels of NEP, ECE1 and ADAM17 mRNAs. In stepwise logistic regression models, high relative expression levels of ECE1 and ADAM17 mRNAs were significantly associated with moderate/advanced periodontitis. CONCLUSION: The present study suggests that the severity of periodontal disease may be associated with the expression of metalloendopeptidase genes, including NEP, ECE1 and ADAM17, in the buccal mucosal epithelium.


Assuntos
Metaloendopeptidases/genética , Mucosa Bucal/enzimologia , Periodontite/enzimologia , Proteínas ADAM/genética , Proteína ADAM17 , Idoso , Perda do Osso Alveolar/enzimologia , Perda do Osso Alveolar/genética , Ácido Aspártico Endopeptidases/genética , Periodontite Crônica/enzimologia , Periodontite Crônica/genética , Enzimas Conversoras de Endotelina , Epitélio/enzimologia , Feminino , Regulação Enzimológica da Expressão Gênica/genética , Hemorragia Gengival/enzimologia , Hemorragia Gengival/genética , Gengivite/enzimologia , Gengivite/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neprilisina/genética , Bolsa Periodontal/enzimologia , Bolsa Periodontal/genética , Periodontite/genética , Periodonto/enzimologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fator de Necrose Tumoral alfa/genética , Adulto Jovem
10.
Science ; 335(6076): 1614-7, 2012 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-22461609

RESUMO

The extinct p-process nuclide (146)Sm serves as an astrophysical and geochemical chronometer through measurements of isotopic anomalies of its α-decay daughter (142)Nd. Based on analyses of (146)Sm/(147)Sm α-activity and atom ratios, we determined the half-life of (146)Sm to be 68 ± 7 (1σ) million years, which is shorter than the currently used value of 103 ± 5 million years. This half-life value implies a higher initial (146)Sm abundance in the early solar system, ((146)Sm/(144)Sm)(0) = 0.0094 ± 0.0005 (2σ), than previously estimated. Terrestrial, lunar, and martian planetary silicate mantle differentiation events dated with (146)Sm-(142)Nd converge to a shorter time span and in general to earlier times, due to the combined effect of the new (146)Sm half-life and ((146)Sm/(144)Sm)(0) values.

14.
Scand J Rheumatol ; 34(6): 464-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16393770

RESUMO

OBJECTIVE: Aseptic loosening is one of the most important problems that can occur after total hip arthroplasty (THA). In this study, we analysed levels of large tenascin-C (TN-C) variants and compared them in pseudosynovial fluid from patients with aseptic loosening after THA with those in synovial fluid from patients undergoing primary THA (control). METHODS: Pseudosynovial fluid samples (n = 24) were obtained by aspiration at the time of revision THA performed due to aseptic loosening. Synovial fluid samples (n = 12) were obtained by aspiration at the time of primary THA. Expression of TN-C splice variants was examined using immunoblotting. TN-C levels were measured using an enzyme-linked immunosorbent assay (ELISA) system that we developed previously. RESULTS: Western blotting showed the presence of large TN-C variants in pseudosynovial fluid of artificial joints with loosening. TN-C levels were approximately three times higher in pseudosynovial fluid of loose artificial joints (median 151.9 ng/mL) than in synovial fluid controls (median 50.1 ng/mL) (p = 0.035). CONCLUSION: Levels of TN-C including large variant subunits are elevated in pseudosynovial fluid of loose artificial joints, indicating that TN-C is a useful novel biochemical marker of loose hip prostheses.


Assuntos
Prótese de Quadril , Osteoartrite do Quadril/metabolismo , Falha de Prótese , Líquido Sinovial/metabolismo , Tenascina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia
15.
Eur J Endocrinol ; 151(2): 277-85, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15296485

RESUMO

OBJECTIVE: N-(2-hydroxyethyl)-nicotinamide nitrate (nicorandil) is a unique anti-anginal agent, reported to act as both an ATP-sensitive K(+) channel opener (PCO) and a nitric oxide donor. It also has an anti-oxidant action. We examined the effects of nicorandil on streptozotocin (STZ)-induced islet beta-cell damage both in vivo and in vitro. DESIGN AND METHODS: STZ-induced diabetic Brown Norway rats (STZ-DM) were fed with nicorandil-containing chow from day 2 (STZ-DM-N48), 3 (STZ-DM-N72), and 4 (STZ-DM-N96) to day 30. Body weight, blood glucose, and plasma insulin were measured every week. For the in vitro assay, neonatal rat islet-rich cultures were performed and cells were treated with nicorandil from 1 h before to 2 h after exposure to STZ for 30 min. Insulin secretion from islet cells was assayed after an additional 24 h of culture. We also observed the effect of nicorandil on the generation of reactive oxygen species (ROS) from rat inslinoma cells (RINm5F). RESULTS: Body weight loss and blood glucose levels of STZ-DM-N48 rats were significantly lower than those of STZ-DM rats. Immunohistochemical staining of insulin showed preservation of insulin-secreting islet beta-cells in STZ-DM-N48 rats. Nicorandil also dose-dependently recovered the insulin release from neonatal rat islet cells treated with STZ in in vitro experiments. Nicorandil did not act as a PCO on neonatal rat islet beta-cells or RINm5F cells, and did not show an inhibitory effect on poly(ADP-ribose) polymerase-1. However, the drug inhibited the production of ROS stimulated by high glucose (22.0 mmol/l) in RINm5F cells. CONCLUSIONS: These results suggested that nicorandil improves diabetes and rat islet beta-cell damage induced by STZ in vivo and in vitro. It protects islet beta-cells, at least partly, via a radical scavenging effect.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Nicorandil/farmacologia , Vasodilatadores/farmacologia , Animais , Glicemia , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Sequestradores de Radicais Livres/farmacologia , Glucagon/metabolismo , Técnicas In Vitro , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Masculino , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Ratos Endogâmicos BN , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
16.
Br J Ophthalmol ; 88(4): 494-6, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15031163

RESUMO

AIM: To report a new form of retinopathy that was observed in patients who had undergone percutaneous coronary intervention (PCI) following acute myocardial infarction (AMI). METHODS: Serial ophthalmological examinations were conducted in 40 patients who underwent PCI. Thirty patients were diagnosed with AMI, and another 10 had stable angina pectoris. RESULTS: Cotton wool spots developed in 17 (57%) patients from the group with AMI undergoing PCI (n = 30) within 2 months. Of these, 41% (seven patients) also developed superficial haemorrhages. Retinopathy was most prominent 1-2 months after AMI and then tended to become quiescent afterwards, without treatment. CONCLUSION: We have identified a new form of retinopathy in patients with AMI that spontaneously subsides without treatment.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Infarto do Miocárdio/complicações , Doenças Retinianas/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Remissão Espontânea
17.
J Sci Med Sport ; 6(4): 379-86, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14723388

RESUMO

The efficacy of electrocardiography (ECG) in the diagnosis of left ventricular (LV) hypertrophy in 890 males, newly recruited to Japanese professional sumo wrestling (15.9 +/- 1.8 years of age, 177.8 +/- 4.7cm, 107.3 +/- 4.7kg), was tested by comparing simple, widely employed ECG criteria (Sokolow-Lyon chest and limb lead voltages and Cornell voltage with repolarisation criteria) with echocardiographic evaluations of LV mass indexed to body surface area. LV hypertrophy was defined as a LV mass index > 2 SD above the mean value obtained from 115 age-matched, normotensive, sedentary, male controls. The prevalence of LV hypertrophy as determined by echocardiography was 9.0% the entire group and was 8.3% among the 484 normotensives. The sensitivities of the three ECG criteria were < or = 36.0%, and their specificities were 70.0-99.0%. In contrast to the Sokolow-Lyon chest lead criteria, the diagnostic performance of the Cornell criteria was little affected by body mass index (BMI), and stepwise regression revealed that BMI did not significantly correlate with Cornell voltage. Still, the diagnostic efficacy of ECG was not sufficient to merit its use for primary recognition of LV hypertrophy among professional sumo wrestlers. Indeed, LV hypertrophy will likely go undetected by ECG in most overweight muscular athletes.


Assuntos
Eletrocardiografia/normas , Hipertrofia Ventricular Esquerda/diagnóstico , Luta Romana , Adolescente , Índice de Massa Corporal , Ecocardiografia , Humanos , Masculino , Sensibilidade e Especificidade
19.
Diabetologia ; 45(5): 735-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12107755

RESUMO

AIMS/HYPOTHESIS: Early stage leukocyte entrapment in the retinal microcirculation (retinal leukostasis) is considered to be one of the important pathogenetic events in diabetic retinopathy. Gliclazide, a sulphonylurea, was reported to reduce leukocyte adhesion to endothelial cells in hyperglycaemia in vitro, thus suggesting possible selective efficacy of this sulphonylurea in preventing leukostasis in diabetic patients. This study evaluated the effectiveness and selectivity of gliclazide treatment on retinal leukostasis of diabetic rats in vivo. METHODS: Streptozotocin (STZ) (65 mg/kg)-induced diabetic rats were divided into three groups (n = 8 each): an untreated diabetic group, a gliclazide-treated diabetic group, and a glibenclamide-treated diabetic group. Gliclazide or glibenclamide was administered orally during a 3-week period. Non-diabetic rats were used as a control (n = 8). Retinal leukostasis was quantitatively evaluated in vivo by acridine orange leukocyte fluorography using a scanning laser ophthalmoscope. RESULTS: The number of leukocytes trapped in the area around the optic disc in the untreated diabetic group (36.9 +/- 5.1 cells) increased significantly compared with the non-diabetic control group (21.9 +/- 2.9 cells; p = 0.0007). The number of leukocytes trapped in the gliclazide-treated diabetic group (23.5 +/- 4.0 cells) decreased significantly compared with untreated diabetic group ( p = 0.0008). In contrast, no reduction of retinal leukostasis was found in the glibenclamide-treated diabetic group (37.8 +/- 5.8 cells; p = 0.7923). CONCLUSION/INTERPRETATION: This suggests that gliclazide could directly improve abnormalities in the retinal microcirculation independent of blood glucose control and possibly have selective therapeutic benefits in preventing early, critical events in diabetic retinopathy compared with other sulphonylurea drugs.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/prevenção & controle , Gliclazida/uso terapêutico , Hipoglicemiantes/uso terapêutico , Leucostasia/prevenção & controle , Animais , Adesão Celular , Leucócitos/efeitos dos fármacos , Leucócitos/fisiologia , Masculino , Ratos , Ratos Endogâmicos BN
20.
Plant Cell Physiol ; 42(11): 1228-33, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11726707

RESUMO

A rice Ca(2+)-dependent protein kinase, OsCDPK7, is a positive regulator commonly involved in the tolerance to cold and salt/drought. We carried out in situ detection of the transcript and immunolocalization of the protein. In the wild-type rice plants under both stress conditions, OsCDPK7 was expressed predominantly in vascular tissues of crowns and roots, vascular bundles and central cylinder, respectively, where water stress occurs most severely. This enzyme was also expressed in the peripheral cylinder of crown vascular bundles and root sclerenchyma. Similar localization patterns with stronger signals were observed in stress-tolerant OsCDPK7 over-expressing transformants with the cauliflower mosaic virus 35S promoter. The transcript of a putative target gene of the OsCDPK7 signaling pathway, rab16A, was also detected essentially in the same tissues upon salt stress, suggesting that the OsCDPK7 pathway operates predominantly in these regions. We propose that the use of the 35S promoter fortuitously strengthened the localized expression of OsCDPK7, resulting in enhancement of the stress signaling in the inherently operating regions leading to improved stress tolerance.


Assuntos
Cálcio/metabolismo , Oryza/metabolismo , Proteínas Quinases/metabolismo , Adaptação Fisiológica , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Imuno-Histoquímica , Oryza/enzimologia , Oryza/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Sais , Transdução de Sinais , Transcrição Gênica , Água/metabolismo
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