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1.
Nat Commun ; 14(1): 2088, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37045846

RESUMO

Kinetic Alfvén waves (KAWs) are ubiquitous throughout the plasma universe. Although they are broadly believed to provide a potential approach for energy exchange between electromagnetic fields and plasma particles, neither the detail nor the efficiency of the interactions has been well-determined yet. The primary difficulty has been the paucity of knowledge of KAWs' spatial structure in observation. Here, we apply a particle-sounding technique to Magnetospheric Multiscale mission data to quantitatively determine the perpendicular wavelength of KAWs from ion gyrophase-distribution observations. Our results show that KAWs' perpendicular wavelength is statistically 2.4[Formula: see text] times proton thermal gyro-radius. This observation yields an upper bound of the energy the majority proton population can reach in coherent interactions with KAWs, that is, roughly 5.76 times proton perpendicular thermal energy. Therefore, the method and results shown here provide a basis for unraveling the effects of KAWs in dissipating energy and accelerating particles in a number of astrophysical systems, e.g., planetary magnetosphere, astrophysical shocks, stellar corona and wind, and the interstellar medium.

2.
Nat Commun ; 13(1): 5593, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151097

RESUMO

Identifying how energy transfer proceeds from macroscales down to microscales in collisionless plasmas is at the forefront of astrophysics and space physics. It provides information on the evolution of involved plasma systems and the generation of high-energy particles in the universe. Here we report two cross-scale energy-transfer events observed by NASA's Magnetospheric Multiscale spacecraft in Earth's magnetosphere. In these events, hot ions simultaneously undergo interactions with macroscale (~[Formula: see text] km) ultra-low-frequency waves and microscale ([Formula: see text] km) electromagnetic-ion-cyclotron (EMIC) waves. The cross-scale interactions cause energy to directly transfer from macroscales to microscales, and finally dissipate at microscales via EMIC-wave-induced ion energization. The direct measurements of the energy transfer rate in the second event confirm the efficiency of this cross-scale transfer process, whose timescale is estimated to be roughly ten EMIC-wave periods about (1 min). Therefore, these observations experimentally demonstrate that simultaneous macroscale and microscale wave-ion interactions provide an efficient mechanism for cross-scale energy transfer and plasma energization in astrophysical and space plasmas.

3.
Eur Rev Med Pharmacol Sci ; 26(1): 6-10, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35049014

RESUMO

OBJECTIVE: Cardiotoxicity is a common adverse effect of many antineoplastic agents, including anthracyclines and paclitaxel. However, it has not been defined as a causal side effect of cisplatin. Here we report on a patient with locally advanced non-small cell lung cancer who developed a cardiotoxic event induced by cisplatin that manifested primarily as arrhythmia. MATERIALS AND METHODS: Intensive cardiac monitoring through electrocardiogram was performed to estimate the severity degree and clinical condition of arrhythmia. RESULTS: The frequency and severity of the arrhythmia had a strong temporal relationship with the administration of cisplatin, that made it likely that cisplatin was responsible for the cardiotoxicity observed. CONCLUSIONS: In the present case report, we discuss the potential factors that may provide pivotal contributions to the patient's susceptibility to cardiotoxicity and review the published studies regarding the cardiotoxic influence of cisplatin. We also outline the critical points that oncologists should be aware of when dealing with such high-risk patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Arritmias Cardíacas/etiologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/efeitos adversos , Humanos , Neoplasias Pulmonares/induzido quimicamente , Paclitaxel/uso terapêutico
4.
Curr Oncol ; 26(2): e175-e179, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31043824

RESUMO

Objectives: In the present study, we explored the real-world efficacy of the immuno-oncology checkpoint inhibitor nivolumab and the tyrosine kinase inhibitor cabozantinib in the second-line setting. Methods: Using the International Metastatic Renal Cell Carcinoma Database Consortium (imdc) dataset, a retrospective analysis of patients with metastatic renal cell carcinoma (mrcc) treated with nivolumab or cabozantinib in the second line after prior therapy targeted to the vascular endothelial growth factor receptor (vegfr) was performed. Baseline characteristics and imdc risk factors were collected. Overall survival (os) and time to treatment failure (ttf) were calculated using Kaplan-Meier curves. Overall response rates (orrs) were determined for each therapy. Multivariable Cox regression analysis was performed to determine survival differences between cabozantinib and nivolumab treatment. Results: The analysis included 225 patients treated with nivolumab and 53 treated with cabozantinib. No significant difference in median os was observed: 22.10 months [95% confidence interval (ci): 17.18 months to not reached] with nivolumab and 23.70 months (95% ci: 15.52 months to not reached) with cabozantinib (p = 0.61). The ttf was also similar at 6.90 months (95% ci: 4.60 months to 9.20 months) with nivolumab and 7.39 months (95% ci: 5.52 months to 12.85 months) with cabozantinib (p = 0.20). The adjusted hazard ratio (hr) for nivolumab compared with cabozantinib was 1.30 (95% ci: 0.73 to 2.3), p = 0.38. When adjusted by imdc criteria and age, the hr was 1.32 (95% ci: 0.74 to 2.38), p = 0.35. Conclusions: Real-world imdc data indicate comparable os and ttf for nivolumab and cabozantinib. Both agents are reasonable therapeutic options for patients progressing after initial first-line vegfr-targeted therapy.


Assuntos
Anilidas/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Nivolumabe/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Idoso , Carcinoma de Células Renais/mortalidade , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/mortalidade , Masculino , Resultado do Tratamento
6.
Zhonghua Wai Ke Za Zhi ; 54(9): 675-9, 2016 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-27587210

RESUMO

OBJECTIVE: To discuss the application of liver visualization technology in complex liver tumor resection at the second hepatic portal area. METHODS: Clinical data of 80 cases who received surgery at the second hepatic portal area from August 2014 to September 2015 in the Third Department of Hepatic Surgery of Eastern Hepatobiliary Surgery Hospital were analyzed retrospectively. There were 58 male and 22 female patients aged from 21 to 70 years with median age of 52 years. Median maximum diameter of tumor was 7.6 cm (3.0 to 17.0 cm). Before surgery, liver dimensional graphics produced by liver visualization technology were taken on all patients to observe the relationship between intrahepatic vasculars and the liver tumor, and to calculate the intended resection range and the remaining liver volume in order to make a proper surgery plan. Suitable hepatic vascular occlusion was applied in the tumor resection. Intrahepatic vessel shape and variation, surgical operation, surgical operation time, manner and time of hepatic vascular occlusion, blood loss, liver resection volume, postoperative complications were observed. RESULTS: There were 23 patients who changed surgery plan after liver visualization technology.There were 44 cases with single main hepatic vein compressed by tumors, 32 cases with 2 main hepatic veins, 4 cases with 3 main hepatic veins compressed by tumors.And there were 58 cases with both hepatic vein and inferior vena cava compressed by tumor. Hepatic segments 6 and 7 was removed in 12 cases, 14 cases, hepatic segments 4, 5 and 8 were removed in 8 cases.Right hepatectomy was carried out in 9 patients and left hepatectomy was carried out in 8 patients. Right trisectionectomy was carried out in 3 patients and left trisectionectomy was applied in 5 patients.Local hepatectomy was performed in 12 patients. Nine patients received associating liver partition and portal vein ligation for staged hepatectomy. Four patients underwent total hepatic vascular exclusion, while 16 patients underwent selective hepatic vascular exclusion. The median surgical time was 132 minutes(80 to 240 minutes). Median blood loss volume was 580 ml(100-5 000 ml). Median volume of hepatic resection was 750 ml(30 to 2 000 ml). One patient needed secondary surgery to stop bleeding as a result of postoperative abdominal bleeding.Complication of postoperative bile leakage occurred in 14 cases.Five patients had pleural effusion requiring invasive therapy.Four patients had ascites requiring invasive therapy. Besides, 5 patients had incisive infection while 2 patients were found with pulmonary infection after surgery and two patients occurred biliary obstruction. There was no death case occurred a result of surgery. CONCLUSIONS: Using liver visualization technology to make surgical operation plan can improve surgical safety of the second hepatic portal area and optimize the operation plan. It can also reduce the risk of blood loss and postoperative complications such as liver failure.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Hepatectomia/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Idoso , Carcinoma Hepatocelular/cirurgia , Feminino , Fluoroscopia , Hemorragia , Veias Hepáticas , Humanos , Ligadura , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Veia Porta , Complicações Pós-Operatórias , Estudos Retrospectivos , Veia Cava Inferior
7.
Br Poult Sci ; 57(5): 699-706, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27352009

RESUMO

The effects of 5 different feeding systems on the performance, carcass traits and organ development were studied in pigeon squabs. The 5 treatments were (1) whole grains of maize, pea and wheat plus concentrate feed; (2)whole grains of maize and wheat plus concentrate feed (CWC); (3) whole grains of maize and pea plus concentrate feed; (4)whole grain of maize plus concentrate feed (CC); and (5) compound feed (CF). Feed intake of parent pigeons increased significantly from 0 to 21 d and it was higher in the CF treatment. Body weight of squabs in the CWC treatment was the highest among the 5 treatments in 4 weeks. Body weight losses of parental pigeons during the rearing period were not significantly different among the 5 treatments. Protein intake in CC and CWC treatments was lower than that of the other three treatments. The CWC treatment had the highest daily weight gain and the lowest feed conversion ratio. Treatments were statistically similar in the relative weight of carcass, breast and thigh. CF had the lower relative weight of abdominal fat. Relative weight of gizzard in the CF treatment was significantly lower than that of CWC. It was concluded that the application of free choice feeding of whole grains of maize and wheat plus concentrate feed increased the body weight of 28-d-old pigeon squabs and decreased the feed conversion rate of parent pigeons. This feeding strategy could be commercially interesting in meat-type pigeon production.

8.
Br J Surg ; 103(4): 348-56, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26780107

RESUMO

BACKGROUND: This study aimed to compare sequential treatment by transcatheter arterial chemoembolization (TACE) and percutaneous radiofrequency ablation (RFA) with partial hepatectomy for hepatocellular carcinoma (HCC) within the Milan criteria. METHODS: In a randomized clinical trial, patients with HCC within the Milan criteria were included and randomized 1 : 1 to the partial hepatectomy group or the TACE + RFA group. The primary outcome was overall survival and the secondary outcome was recurrence-free survival. RESULTS: Two hundred patients were enrolled. The 1-, 3- and 5-year overall survival rates were 97·0, 83·7 and 61·9 per cent for the partial hepatectomy group, and 96·0, 67·2 and 45·7 per cent for the TACE + RFA group (P = 0·007). The 1-, 3- and 5-year recurrence-free survival rates were 94·0, 68·2 and 48·4 per cent, and 83·0, 44·9 and 35·5 per cent respectively (P = 0·026). On Cox proportional hazard regression analysis, HBV-DNA (hazard ratio (HR) 1·76; P = 0·006), platelet count (HR 1·00; P = 0·017) and tumour size (HR 1·90; P < 0·001) were independent prognostic factors for recurrence-free survival, and HBV-DNA (HR 1·61; P = 0·036) was a risk factor for overall survival. The incidence of complications in the partial hepatectomy group was higher than in the TACE + RFA group (23·0 versus 11·0 per cent respectively; P = 0·024). CONCLUSION: For patients with HCC within the Milan criteria, partial hepatectomy was associated with better overall and recurrence-free survival than sequential treatment with TACE and RFA. REGISTRATION NUMBER: ACTRN12611000770965 (http://www.anzctr.org.au/).


Assuntos
Carcinoma Hepatocelular/terapia , Ablação por Cateter/métodos , Quimioembolização Terapêutica/métodos , Hepatectomia/métodos , Neoplasias Hepáticas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , China/epidemiologia , Terapia Combinada , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento
9.
Eur Rev Med Pharmacol Sci ; 19(20): 3940-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26531283

RESUMO

OBJECTIVE: To discuss the protective mechanisms of atorvastatin treatment for isoproterenol (ISO)-induced chronic heart failure. MATERIALS AND METHODS: The rats were randomly divided into three groups: normal group (n = 15, age-matched normal adult rats), ISO group (n = 11, ISO induced heart failure) and atorvastatin group (n = 14, ISO induced lesion but received atorvastatin treatment). The cardiac function was evaluated by echocardiography and hemodynamics analysis. In addition, the Rac1 activity in the myocardium and the expression levels of Rac1, p47phox and p67phox were measured by RT-PCR and western blot. RESULTS: Rats in ISO group developed into heart failure with decreased cardiac function. The Rac1, p47phox and p67phox mRNA expressions and ROS release were increased in ISO group. Atorvastatin treatment improved cardiac function of rats with isoproterenol-induced chronic heart failure and decreased the Rac1, p47phox and p67phox mRNA expressions. Also, membrane protein expression of Rac1 and ROS release decreased significantly. CONCLUSIONS: Atorvastatin may improve cardiac function of rats with heart failure via inhibiting Rac1/P47phox/P67phox-mediated ROS release.


Assuntos
Atorvastatina/uso terapêutico , Insuficiência Cardíaca/metabolismo , NADH NADPH Oxirredutases/metabolismo , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Atorvastatina/farmacologia , Doença Crônica , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Masculino , NADH NADPH Oxirredutases/antagonistas & inibidores , NADPH Oxidases/antagonistas & inibidores , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/antagonistas & inibidores , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores
10.
Poult Sci ; 93(8): 1883-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24931968

RESUMO

An experiment was conducted to evaluate the effect of free-range days on growth performance, carcass yield, meat quality, and lymphoid organ index of a local chicken breed. In total, 1,000 one-day-old male Suqin yellow chickens were raised for 21 d. On d 21, 720 birds with similar BW (536 ± 36 g) were selected and randomly assigned to free-range treatment at 21, 28, 35, and 42 d of age (assigned to free-range treatment for 21, 14, 7, and 0 d, respectively). Each treatment was represented by 5 replicates (pens) containing 36 birds (180 birds per treatment). All the birds were raised in indoor floor pens measuring 1.42 × 1.42 m (2 m(2), 18 birds/m(2)) in conventional poultry research houses before free-range treatment. In the free-range treatment, the chickens were raised in indoor floor houses measuring 3 × 5 m (15 m(2), 2.4 birds/m(2)). In addition, they also had an outdoor free-range paddock measuring 3 × 8 m (24 m(2), 1.5 birds/m(2)). The BW of birds after being assigned to free-range treatment for 7 d decreased significantly compared with that in the conventional treatment (P < 0.05). However, there was no effect of the free-range days on the BW at 42 d of age (P > 0.05). The daily weight gain, feed per gain, daily feed intake, and mortality from 21 to 42 d of age were unaffected by free-range days (P > 0.05). At 42 d of age, the breast yield increased linearly with increasing free-range days (P < 0.05), whereas the thigh, leg, thigh bone, and foot yields decreased linearly (P < 0.05). The lung yield showed a significant increasing and then decreasing quadratic response to increasing free-range days (P < 0.05). The water-holding capacity of the thigh muscle decreased linearly with increasing free-range days (P < 0.05), whereas there was no significant difference in the meat color, shear force, and muscle pH (P > 0.05). The absolute thymus weight and thymus:BW ratio showed a significant increasing and then decreasing quadratic response to increasing free-range days (P < 0.05). The findings of this study suggest that increasing free-range days advantageously affects breast yield, but decreases thigh, leg, thigh bone, and foot yields as well as the water-holding capacity of thigh. No evidence was found that increasing free-range days caused changes in growth performance, meat quality, and lymphoid organs except for changes in water-holding capacity and thymus.


Assuntos
Peso Corporal , Galinhas/fisiologia , Abrigo para Animais , Tecido Linfoide/química , Carne/análise , Criação de Animais Domésticos , Animais , Galinhas/genética , Galinhas/crescimento & desenvolvimento , China , Masculino , Distribuição Aleatória , Fatores de Tempo
11.
Genet Mol Res ; 13(1): 1447-55, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24634243

RESUMO

Dimocarpus longan Lour. is an edible and traditional herb in China, commonly referred to as longon. An improved randomly amplified polymorphic DNA (RAPD) protocol was here developed in order to determine the geographical origins of D. longan samples collected from 5 provinces in the southern and southwestern areas of China, including Sichuan, Hainan, Fujian, Guangdong, and Guangxi. Generally, the improved RAPD method generated good fingerprinting of the 5 samples using the selected 17 primers. In particular, primers SBS-A5, SBS-A13, SBS-I9, SBS-I20, SBS-M1, and SBS-Q12 produced distinguishable bands that clearly separated all 5 cultivars, suggesting that there are variations in RAPD genetic sites among the samples. The similarity index ranged from 0.69 to 0.76. The Sichuan and Hainan clades clustered together with a 0.73 similarity index. The Guangxi and Fujian clades clustered together with a 0.76 similarity index, and they formed the sister clade to the Sichuan/Hainan clade with a 0.71 similarity index. The Guangdong clade was in a basal polytomy with a 0.70 similarity index. Based on the abundant DNA polymorphisms, these longan accessions are distinguishable using our improved RAPD technique. Therefore, RAPD analysis is an effective technique in distinguishing the geographical origins of D. longan. Moreover, the improved method could also be employed for a variety of applications including genetic diversity and fingerprinting analyses.


Assuntos
Técnica de Amplificação ao Acaso de DNA Polimórfico , Traqueófitas/classificação , Traqueófitas/genética , China , Marcadores Genéticos , Filogenia , Plantas Medicinais/classificação , Plantas Medicinais/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos
12.
Nat Commun ; 4: 1466, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23403567

RESUMO

An understanding of the transport of solar wind plasma into and throughout the terrestrial magnetosphere is crucial to space science and space weather. For non-active periods, there is little agreement on where and how plasma entry into the magnetosphere might occur. Moreover, behaviour in the high-latitude region behind the magnetospheric cusps, for example, the lobes, is poorly understood, partly because of lack of coverage by previous space missions. Here, using Cluster multi-spacecraft data, we report an unexpected discovery of regions of solar wind entry into the Earth's high-latitude magnetosphere tailward of the cusps. From statistical observational facts and simulation analysis we suggest that these regions are most likely produced by magnetic reconnection at the high-latitude magnetopause, although other processes, such as impulsive penetration, may not be ruled out entirely. We find that the degree of entry can be significant for solar wind transport into the magnetosphere during such quiet times.

13.
Eur J Surg Oncol ; 39(2): 125-30, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23246114

RESUMO

BACKGROUND AND AIM: Selective hepatic vascular exclusion (SHVE) has not been widely used because of difficulty in extrahepatic isolation of hepatic veins. This study aims to compare the results of SHVE using tourniquets or Satinsky clamps on major hepatic veins in partial hepatectomy for liver tumors involving the roots of hepatic veins. METHODS: Between June 2008 and March 2012, a randomized controlled trial was performed on patients undergoing liver resection to compare selective hepatic vascular exclusion using tourniquets or Satinsky clamps in partial hepatectomy. In the tourniquet group, the hepatic veins were completely isolated and occluded with tourniquets. In the Satinsky clamp group, the hepatic veins were dissected on the anterior and side walls only and they were clamped directly by Satinsky clamps. RESULTS: The time for dissecting hepatic veins was significantly shorter in the Satinsky clamp group (7.5 ± 6.6 min vs 21.3 ± 7.4 min) than the tourniquet group. In the tourniquet group, 5 hepatic veins could not be completely isolated and encircled. In 4 additional patients the hepatic vein was slightly torn during dissection. These 9 patients received successful occlusion using Satinsky clamps. In the Satinsky group, all occlusion of the hepatic vein was successful. There was a significant difference in the success rate in hepatic vein occlusion using the Satinsky and the tourniquet groups 60/60 vs 51/60, P = 0.0018. CONCLUSIONS: Both techniques of hepatic vein occlusion were safe and efficacious. As the use of Satinsky clamps is safer, easier and took less time, it is recommended.


Assuntos
Hepatectomia/instrumentação , Hepatectomia/métodos , Veias Hepáticas/patologia , Veias Hepáticas/cirurgia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/cirurgia , Torniquetes , Procedimentos Cirúrgicos Vasculares/instrumentação , Adolescente , Adulto , Idoso , Perda Sanguínea Cirúrgica/prevenção & controle , Feminino , Hepatectomia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Instrumentos Cirúrgicos/estatística & dados numéricos , Torniquetes/estatística & dados numéricos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/métodos
14.
Phys Rev Lett ; 109(20): 205001, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23215495

RESUMO

Electrons streaming along the magnetic field direction are frequently observed in the plasma sheet of Earth's geomagnetic tail. The impact of these field-aligned electrons on the dynamics of the geomagnetic tail is however not well understood. Here we report the first detection of field-aligned electrons with fluxes increasing at ~1 keV forming a "cool" beam just prior to the dissipation of energy in the current sheet. These field-aligned beams at ~15 R(E) in the plasma sheet are nearly identical to those commonly observed at auroral altitudes, suggesting the beams are auroral electrons accelerated upward by electric fields parallel (E([parallel])) to the geomagnetic field. The density of the beams relative to the ambient electron density is δn(b)/n(e)~5-13% and the current carried by the beams is ~10(-8)-10(-7) A m(-2). These beams in high ß plasmas with large density and temperature gradients appear to satisfy the Bohm criteria to initiate current driven instabilities.

15.
Phys Rev Lett ; 108(6): 061102, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401049

RESUMO

Earth's bow shock is a collisionless shock wave but entropy has never been directly measured across it. The plasma experiments on Cluster and Double Star measure 3D plasma distributions upstream and downstream of the bow shock allowing calculation of Boltzmann's entropy function H and his famous H theorem, dH/dt≤0. The collisionless Boltzmann (Vlasov) equation predicts that the total entropy does not change if the distribution function across the shock becomes nonthermal, but it allows changes in the entropy density. Here, we present the first direct measurements of entropy density changes across Earth's bow shock and show that the results generally support the model of the Vlasov analysis. These observations are a starting point for a more sophisticated analysis that includes 3D computer modeling of collisionless shocks with input from observed particles, waves, and turbulences.

16.
J Appl Microbiol ; 112(1): 205-13, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22008096

RESUMO

AIMS: To investigate the distribution of staphylococcal enterotoxin genes (se) and the molecular features of community-associated methicillin-sensitive/resistant Staphylococcus aureus (CA-MSSA/MRSA) isolates in the nostrils of healthy pets and their owners. METHODS AND RESULTS: A total of 114 Staph. aureus isolates were identified from 1563 nasal swab samples, and CA-MRSA accounted for 20·2% (n = 23) of the total identified isolates. CA-MRSA isolates (91·3%, 21/23) harboured higher percentage of se than did CA-MSSA isolates (58·2%, 53/91) (P < 0·01), and the two highest se profiles of CA-MRSA were seb-sek-seq (42·9%, 9/21) and seb-sek-seq-sep (28·6%, 6/21). Of the MSSAs, 42·8% (39/91) were resistant to at least one antimicrobial drug and 8·8% (8/91) were multidrug resistant (MDR). We identified nine staphylocoagulase (SC) types (I-VIII and X) and three multilocus sequence types (ST59-MRSA-IV/V, ST-239-MRSA-V and ST241-MRSA-V). SC VII (23·4%, 22/94), a staphylococcal food poisoning isolate found mainly in Japan, and ST-59-MRSA-IV/V (85%, 17/20), a widespread CA-MRSA clone found mainly in Taiwan, both were the most predominant types. Phylogenetic analysis together with se and molecular characteristics obtained using pulsed-field gel electrophoresis showed that high levels of antimicrobial resistance and the se-carrying clone ST59-MRSA-IV/V-SC VII were all clustered in genogroup 5. CONCLUSIONS: The CA-MRSA clone of se-carrying-MDR-ST-59-IV/V-SC VII was identified predominantly in this study, and this clone might play a significant role in staphylococcal food poisoning in community settings. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first study focussing on enterotoxin-carrying CA-MRSA/MSSA in pets and their owners, and the results support the future warnings in animal-human bond caused by CA-staphylococci in the commonwealth and the need to take cautions worldwide.


Assuntos
Heterogeneidade Genética , Staphylococcus aureus Resistente à Meticilina , Filogenia , Staphylococcus aureus , Animais , Anti-Infecciosos/farmacologia , Gatos , Coagulase/genética , DNA Bacteriano/genética , Cães , Eletroforese em Gel de Campo Pulsado , Enterotoxinas/genética , Genótipo , Humanos , Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/enzimologia , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Prevalência , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , Staphylococcus aureus/genética , Taiwan
17.
J Dent Res ; 90(8): 1013-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21586666

RESUMO

Dental pulp has intrinsic capacity for self-repair. However, it is not clear whether dental pulp cells can be recruited endogenously for regenerating pulp tissues, including mineralizing into dentin. This work is based on a hypothesis that dental pulp stem/progenitor cells can be induced to migrate by chemotactic cytokines and act as endogenous cell sources for regeneration and mineralization. Dental stem cells (DSCs) were isolated from adult human tooth pulp and seeded on the surfaces of 3D collagen gel cylinders that were incubated in chemically defined media with stromal-derived factor-1α (SDF1), basic fibroblast growth factor (bFGF), or bone morphogenetic protein-7 (BMP7). Significantly more cells were recruited into collagen gel by SDF1 or bFGF than without cytokines in 7 days, whereas BMP7 had little effect on cell recruitment. BMP7, however, was highly effective, equally to dexamethasone, in orchestrating mineralization of cultured DSCs. Cell membrane receptors for SDF1, bFGF, and BMP7 were up-regulated in treated DSCs. Upon in vivo delivery, bFGF induced re-cellularization and re-vascularization in endodontically treated human teeth implanted into the dorsum of rats. Thus, endogenous dental pulp cells, including stem/progenitor cells, may be recruited and subsequently differentiated by chemotaxis of selective cytokines in the regeneration of dental pulp.


Assuntos
Células-Tronco Adultas/fisiologia , Quimiocina CXCL12/farmacologia , Quimiotaxia/efeitos dos fármacos , Polpa Dentária/citologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Regeneração/efeitos dos fármacos , Adolescente , Adulto , Células-Tronco Adultas/efeitos dos fármacos , Células-Tronco Adultas/metabolismo , Análise de Variância , Animais , Proteína Morfogenética Óssea 7/farmacologia , Receptores de Proteínas Morfogenéticas Ósseas/biossíntese , Calcificação Fisiológica , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Colágeno , Necrose da Polpa Dentária/tratamento farmacológico , Determinação de Ponto Final , Feminino , Humanos , Masculino , Neovascularização Fisiológica , Ratos , Receptores CXCR4/biossíntese , Receptores de Fatores de Crescimento de Fibroblastos/biossíntese , Transplante de Células-Tronco , Tela Subcutânea , Alicerces Teciduais , Dente não Vital/tratamento farmacológico
18.
J Agric Food Chem ; 58(12): 7233-8, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20509690

RESUMO

This study investigated the inhibition of enzymatic hydrolysis by unbound lignin (soluble and insoluble) with or without the addition of metal compounds. Sulfonated, Organosolv, and Kraft lignin were added in aqueous enzyme-cellulose systems at different concentrations before hydrolysis. The measured substrate enzymatic digestibility (SED) of cellulose was decreased by 15% when SL was added to a concentration of 0.1 g/L due to nonproductive adsorption of enzymes onto lignin. Cu(II) and Fe(III) were found to inhibit enzymatic cellulose hydrolysis in the presence of lignin. Ca(II) and Mg(II) were found to reduce or eliminate nonproductive enzyme adsorption by the formation of lignin-metal complex. The addition of Ca(II) or Mg(II) to a concentration of 10 mM can almost completely eliminate the reduction in SED caused by the nonproductive enzyme adsorption onto the lignins studied (SL, OL, or KL at concentration of 0.1 g/L). Ca(II) was also found to reduce the inhibitive effect of bound lignin in pretreated wood substrate, suggesting that Ca(II) can also form complex with bound lignin on pretreated solid lignocelluloses. Significant improvement in SED of about over 27% of a eucalyptus substrate produced by sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) was achieved with the application of Ca(II).


Assuntos
Celulases/química , Celulose/química , Lignina/química , Metais/química , Complexos de Coordenação/química , Estabilidade Enzimática , Hidrólise , Cinética , beta-Glucosidase/química
19.
Br J Surg ; 97(1): 50-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20013928

RESUMO

BACKGROUND: Adequate control of bleeding is crucial during liver resection. This study analysed the safety and efficacy of hepatectomy under total hepatic vascular exclusion (THVE) in patients with tumours encroaching or infiltrating the hepatic veins and/or the inferior vena cava (IVC). METHODS: All patients undergoing liver resection with THVE between January 2000 and July 2006 were identified from a prospectively collected database containing 2400 patients. Data on patient demographics, surgical procedure and outcome were collected. RESULTS: A total of 87 patients scheduled for liver resection under THVE were identified, 77 with malignant tumours and ten with benign disease. THVE could not be used in two patients (2 per cent) owing to haemodynamic intolerance during trial clamping. Seventeen patients received simultaneous clamping of the portal triad and vena cava, and 68 had portal triad clamping followed by concomitant portal and vena cava clamping. The mean(s.d.) duration of THVE was 28.3(7.5) and 18.7(5.2) min respectively. Overall postoperative complication and operative mortality rates were 53 and 2 per cent respectively. Mean(s.d.) hospital stay was 16.8(4.7) days. CONCLUSION: Major hepatic resection for tumours encroaching on the hepatic veins or IVC can be carried out under THVE with reasonable morbidity and mortality.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Embolização Terapêutica/métodos , Hepatectomia/métodos , Hepatopatias/cirurgia , Fígado/irrigação sanguínea , Constrição , Feminino , Técnicas Hemostáticas , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
20.
Water Sci Technol ; 59(5): 987-94, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19273898

RESUMO

Coupled granules are self-immobilized aggregates of microorganisms under micro aerobic conditions, which have the dissolved oxygen (DO) level of 0.6 mg.L(-1). The effects of DO concentration on pentachlorophenol (PCP) reduction and its microbial community were investigated in a coupled anaerobic and aerobic reactor. Both the diversity and the dynamicity of the Eubacteria and Archaea community, which were responsible for PCP degradation, were evaluated by means of amplification by polymerase chain reaction (PCR) and separation using the denaturing gradient gel electrophoresis (DGGE) technique. The results demonstrated a major shift in the Eubacteria and Archaea community as the mixed aerobic and anaerobic seeding sludge (1:1 by volume) developed into coupled granules and finally acclimated with PCP throughout the experiment period within 60 days. The numbers of the Eubacteria population decreased from 20, 16 to 11; Shannon diversity index decreased from 2.75, 2.53 to 2.10. In contrast, the number of the Archaea population increased from 12, 14 to 18; and Shannon diversity index increased from 1.87, 1.88 to 2.43. Phylogenetic analysis based on 16SrDNA genes showed the dominance Sphingomonas, Desulfobulbus, Proteobacteria, Actinobacterium, Methanogenic and some uncultured bacteria in the PCP-degrading coupled granules. Microorganism community construction of coupled granules was also deduced.


Assuntos
Reatores Biológicos/microbiologia , Pentaclorofenol/metabolismo , DNA Bacteriano/genética , Filogenia
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