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1.
J Radiol Prot ; 40(4): 947-961, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32964860

RESUMO

The lunar surface is directly and continuously exposed to Galactic Cosmic ray (GCR) particles and Solar energetic particles (SEPs) due to the lack of atmosphere and lunar magnetic field. These charged particles interact with the lunar surface materials producing secondary radiations such as neutrons and gamma rays. In a departure from precise GCR and SEP data, we estimated the effective dose equivalent at the lunar surface and in a lunar lava tube in this paper by using PHITS, a Monte Carlo simulation tool. The effective dose equivalent due to GCR particles at the lunar surface reached 416.0 mSv yr-1 and that due to SEPs reached 2190 mSv/event. On the other hand, the vertical hole of the lava tube provides significant radiation protection. The exposure by GCR particles at the bottom of the vertical hole with a depth of 43 m was found to be below 30 mSv yr-1 while inside a horizontal lava tube, the value was less than 1 mSv yr-1 which is the reference value for human exposure on the Earth. We expect that the lunar holes will be useful components in the practical design of a lunar base to reduce radiation risk and to expand mission terms.

2.
J Pediatr Orthop ; 40(5): e380-e384, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31688817

RESUMO

BACKGROUND: Hamstring surgical lengthening (HSL) has been frequently performed for the correction of knee flexion deformity in cerebral palsy (CP), although recurrence is described in long-term follow-up. Repeat hamstring surgical lengthening (RHSL) can be an option for recurrent knee flexion deformity; however, the results of this approach are still controversial. The purpose of this study was to compare the results of primary HSL and RHSL in CP. METHODS: Patients with spastic diplegic CP, Gross Motor Function Classification System levels I to III, underwent bilateral medial HSL with complete documentation in the gait laboratory before and after the intervention, were included in the study. A total of 229 subjects met the inclusion criteria and were divided into 2 groups: group A was formed by those who received medial HSL for the first time (185 patients), and group B was composed of individuals who underwent RHSL (44 patients). Clinical and kinematic parameters were evaluated before and after the intervention, and the results compared. RESULTS: The groups were matched with regard to sex distribution, Gross Motor Function Classification System levels, and follow-up time (>2 y). Popliteal angle was reduced in groups A (60.3 to 51.4 degrees, P<0.001) and B (56.1 to 51.5 degrees, P=0.001) after the intervention. Knee flexion at initial contact was reduced from 40.8 to 28.9 degrees in group A (P<0.001) and from 40.4 to 35.1 degrees in group B (P=0.001). Reduction of minimum knee flexion in the stance phase (24.9 to 17.5 degrees, P<0.001) and improvement of the Gait Deviation Index (52.9 to 60.2, P<0.001) occurred only in group A. Anterior pelvic tilt (APT) increased in groups A (from 17 to 19.5 degrees, P<0.001) and B (from 14.9 to 19.4 degrees, P<0.001) after treatment. Finally, in the comparison between groups, the reduction of knee flexion at initial contact was more significant in group A (P<0.001), whereas the increase of APT was higher in group B. CONCLUSIONS: In the present study, the improvement of knee extension during the stance phase was observed only after the primary medial HSL. Moreover, the increase of APT was more significant when RHSL was performed. LEVEL OF EVIDENCE: Level III.


Assuntos
Paralisia Cerebral/cirurgia , Marcha , Músculos Isquiossurais/cirurgia , Tendões dos Músculos Isquiotibiais/cirurgia , Amplitude de Movimento Articular , Reoperação , Adolescente , Fenômenos Biomecânicos , Paralisia Cerebral/complicações , Paralisia Cerebral/fisiopatologia , Criança , Contratura/etiologia , Contratura/cirurgia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Postura , Recidiva , Estudos Retrospectivos , Tenotomia , Resultado do Tratamento
3.
J Pediatr Orthop B ; 28(4): 327-331, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30499862

RESUMO

The aim of this study was to compare semitendinosus transfer to distal femur (STTX) to semitendinosus surgical lengthening (STL) regarding the increase of anterior pelvic tilt after flexed knee gait treatment. Thirty-nine patients were evaluated, and they were divided according surgical procedures at knees: STL group (22 patients/44 knees), which included patients who received medial hamstrings surgical lengthening as part of multilevel approach, and STTX group (17 patients/34 knees), which was represented by patients who underwent orthopedic surgery including a STTX instead of STL. In the present study, the mean anterior pelvic tilt increased in all groups after treatment and STTX was not effective to prevent it in a medium-term follow-up.


Assuntos
Paralisia Cerebral/fisiopatologia , Fêmur/fisiopatologia , Fêmur/cirurgia , Marcha , Tendões dos Músculos Isquiotibiais/transplante , Osteotomia , Adolescente , Fenômenos Biomecânicos , Criança , Pré-Escolar , Feminino , Músculos Isquiossurais , Quadril/fisiopatologia , Humanos , Masculino , Espasticidade Muscular , Pelve/fisiopatologia , Período Pós-Operatório , Postura , Amplitude de Movimento Articular , Estudos Retrospectivos , Rotação
4.
Nephrology (Carlton) ; 23(9): 805-814, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29575280

RESUMO

Acute kidney injury is common and associated with negative renal and patient outcomes. The human kidney has a real but limited regeneration capacity. Understanding renal regeneration may allow us to manipulate this process and thus develop therapeutic weapons to improve patients' outcome. In the first part of this paper we discuss the clinical factors associated with renal recovery: baseline patient particularities, acute kidney injury characteristics and the medical approach taken in the short and long-term. In the second part, the cellular and molecular mechanisms underlying renal regeneration are explored. The immune system seems to have an important role, first promoting inflammation and then tissue healing. Other players, such as cellular senescence, mitochondrial dysfunction, renal haemodynamics and metabolic reprogramming also have a role in renal regeneration. We aim to develop a short review of renal regeneration, offering a holistic view of this process.


Assuntos
Injúria Renal Aguda/fisiopatologia , Rim/fisiopatologia , Regeneração , Injúria Renal Aguda/imunologia , Injúria Renal Aguda/patologia , Injúria Renal Aguda/terapia , Animais , Proliferação de Células , Humanos , Rim/imunologia , Rim/patologia , Prognóstico , Recuperação de Função Fisiológica , Fatores de Risco , Transdução de Sinais
5.
Int J STD AIDS ; 29(7): 714-719, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29343165

RESUMO

The presence of human immunodeficiency virus (HIV)-related kidney disease is an important cause of mortality and morbidity. HIV infection induces renal injury by direct cytotoxicity or immune complex-mediated glomerulonephritis in patients with genetic susceptibility factors. In the last decades, with the development and diffusion of combination antiretroviral therapy, which has prolonged patient survival, there has been a shift in the spectrum of renal diseases in HIV-infected patients, with the decrease of glomerular diseases and increase in the role of nephrotoxicity and co-morbidities. This review provides a contemporary and critical review on the main renal syndromes occurring in HIV-infected patients.


Assuntos
Nefropatia Associada a AIDS/etiologia , Injúria Renal Aguda/complicações , Antirretrovirais/efeitos adversos , Infecções por HIV/tratamento farmacológico , Nefropatias/complicações , Rim/efeitos dos fármacos , Nefropatia Associada a AIDS/patologia , Injúria Renal Aguda/fisiopatologia , Antirretrovirais/uso terapêutico , Antirretrovirais/toxicidade , Infecções por HIV/complicações , Infecções por HIV/virologia , Humanos , Rim/patologia , Nefropatias/fisiopatologia
6.
Clin Nephrol ; 89(2): 120-122, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29231161

RESUMO

Peritoneopleural shunt is an uncommon complication of peritoneal dialysis (PD) usually presenting early as a right pleural transudate. Peritoneopericardial shunt is an even rarer entity in PD, almost never occurring spontaneously. We present the case of a 37-year-old woman on PD for 24 months exhibiting a left pleural and pericardial effusion following pneumonia. Pleural fluid was initially compatible with an exudate with a high glucose concentration and later with a transudate. In order to clarify the suspicion of an ongoing shunt an abdominal scintigraphy was performed confirming the diagnosis of a peritoneopleuropericardial communication. This case underlines the importance of considering this unusual diagnosis in a patient on long-term PD. Its timely diagnosis is important to stop PD and start hemodialysis.
.


Assuntos
Derrame Pericárdico/diagnóstico , Derrame Pericárdico/etiologia , Diálise Peritoneal/efeitos adversos , Derrame Pleural/diagnóstico , Derrame Pleural/etiologia , Insuficiência Renal Crônica/terapia , Adulto , Feminino , Humanos
7.
Science ; 353(6300): 669-73, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27516595

RESUMO

The deuteron is the simplest compound nucleus, composed of one proton and one neutron. Deuteron properties such as the root-mean-square charge radius rd and the polarizability serve as important benchmarks for understanding the nuclear forces and structure. Muonic deuterium µd is the exotic atom formed by a deuteron and a negative muon µ(-). We measured three 2S-2P transitions in µd and obtain r(d) = 2.12562(78) fm, which is 2.7 times more accurate but 7.5σ smaller than the CODATA-2010 value r(d) = 2.1424(21) fm. The µd value is also 3.5σ smaller than the r(d) value from electronic deuterium spectroscopy. The smaller r(d), when combined with the electronic isotope shift, yields a "small" proton radius r(p), similar to the one from muonic hydrogen, amplifying the proton radius puzzle.

8.
Nat Prod Res ; 30(11): 1289-92, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26158209

RESUMO

The aim of this work was to evaluate the antimicrobial activity of ethanol (EEAC) and hexane (HFAC) extracts from the stem bark of Anadenanthera colubrina (Vell.) Brenan var. cebil alone or in combination with aminoglycosides against multi-drug resistant (MDR) bacteria. Minimal inhibitory concentrations (MICs) of the extracts were determined by using microdilution assay. For the evaluation of extracts as modulators of antibiotic resistance, MICs of neomycin and amikacin were determined in presence or absence of each compound at sub-inhibitory concentrations. Both EEAC and HFAC did not show antimicrobial activity against MDR strains tested. However, the addition of EEAC and HFAC enhanced the activity of neomycin and amikacin against Staphylococcus aureus SA10 strain. When the natural products were replaced by chlorpromazine, the same effect was observed. Anadenanthera colubrine var. cebil may be a source of phytochemicals able to potentiate the aminoglycoside activity against MDR S. aureus by the inhibition of efflux pump.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Fabaceae/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Amicacina/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Neomicina/farmacologia , Compostos Fitoquímicos/farmacologia
9.
Photochem Photobiol Sci ; 13(12): 1650-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25360993

RESUMO

An ethanol extract and different partition fractions obtained from Lippia origanoides H.B.K. were assayed for light-mediated activity against strains of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Identical assays were conducted with and without exposure to UV-A (400-315 nm) light to test for light enhanced activity. The ethanol extract and dichloromethane fraction showed light-mediated activity against the S. aureus strain, but not against the E. coli strain. The dichloromethane fraction was more active than the ethanol extract. Naringenin did not display light-mediated activity against the tested bacteria, indicating that the light-mediated antimicrobial activity of the dichloromethane fraction is not due to its major component. The results represent the first report of light-mediated antimicrobial activity of Lippia origanoides and show that its phytochemicals could be used as light-mediated antimicrobial agents.


Assuntos
Antibacterianos/química , Lippia/química , Fármacos Fotossensibilizantes/química , Extratos Vegetais/química , Raios Ultravioleta , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Flavanonas/química , Cloreto de Metileno/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação
11.
Science ; 339(6118): 417-20, 2013 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-23349284

RESUMO

Accurate knowledge of the charge and Zemach radii of the proton is essential, not only for understanding its structure but also as input for tests of bound-state quantum electrodynamics and its predictions for the energy levels of hydrogen. These radii may be extracted from the laser spectroscopy of muonic hydrogen (µp, that is, a proton orbited by a muon). We measured the 2S(1/2)(F=0)-2P(3/2)(F=1) transition frequency in µp to be 54611.16(1.05) gigahertz (numbers in parentheses indicate one standard deviation of uncertainty) and reevaluated the 2S(1/2)(F=1)-2P(3/2)(F=2) transition frequency, yielding 49881.35(65) gigahertz. From the measurements, we determined the Zemach radius, r(Z) = 1.082(37) femtometers, and the magnetic radius, r(M) = 0.87(6) femtometer, of the proton. We also extracted the charge radius, r(E) = 0.84087(39) femtometer, with an order of magnitude more precision than the 2010-CODATA value and at 7σ variance with respect to it, thus reinforcing the proton radius puzzle.

12.
Rev. bras. farmacogn ; 22(6): 1259-1267, Nov.-Dec. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-659042

RESUMO

The essential oil (EO) of aerial parts of Lantana camara L., Verbenaceae, from Simões, Piaui, Northeast of Brazil, were obtained by hydrodistillation and analyzed by GC-FID and GC-MS techniques. In total, 68 compounds were identified. The most representative compounds of the oil were mono and sesquiterpenes. The main compounds found in the oil of the leaves in different months were β-caryophyllene (10.5%, in June of 2009), sabinene (7.98%, in September of 2008), limonene (7.68%, in September of 2008), spathulenol (11.64%, in September of 2008). The oil from stems of L. camara was characterized by a largest amount of sesquiterpenoids, with spatulenol (15.9%) and caryophyllene oxide (17.1% in June of 2009), as main components. β-Gurjunene (32.7%, in September of 2008) was the most prominent compound in the stems oils, which was absent or at very low relative abundance in leaves. L. camara essential oils from leaves were cytotoxic to V79 mammalian cells and also to Artemia salina, showing 50% lethal concentration (LC50) values from 0.23 µg/mL. The in vitro data obtained in this study suggested that EO may also be effective treating yeast infection in patients infected with fluconazole and terbinafine resistant isolates, but its toxicity must be monitored carefully.

13.
Nature ; 466(7303): 213-6, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20613837

RESUMO

The proton is the primary building block of the visible Universe, but many of its properties-such as its charge radius and its anomalous magnetic moment-are not well understood. The root-mean-square charge radius, r(p), has been determined with an accuracy of 2 per cent (at best) by electron-proton scattering experiments. The present most accurate value of r(p) (with an uncertainty of 1 per cent) is given by the CODATA compilation of physical constants. This value is based mainly on precision spectroscopy of atomic hydrogen and calculations of bound-state quantum electrodynamics (QED; refs 8, 9). The accuracy of r(p) as deduced from electron-proton scattering limits the testing of bound-state QED in atomic hydrogen as well as the determination of the Rydberg constant (currently the most accurately measured fundamental physical constant). An attractive means to improve the accuracy in the measurement of r(p) is provided by muonic hydrogen (a proton orbited by a negative muon); its much smaller Bohr radius compared to ordinary atomic hydrogen causes enhancement of effects related to the finite size of the proton. In particular, the Lamb shift (the energy difference between the 2S(1/2) and 2P(1/2) states) is affected by as much as 2 per cent. Here we use pulsed laser spectroscopy to measure a muonic Lamb shift of 49,881.88(76) GHz. On the basis of present calculations of fine and hyperfine splittings and QED terms, we find r(p) = 0.84184(67) fm, which differs by 5.0 standard deviations from the CODATA value of 0.8768(69) fm. Our result implies that either the Rydberg constant has to be shifted by -110 kHz/c (4.9 standard deviations), or the calculations of the QED effects in atomic hydrogen or muonic hydrogen atoms are insufficient.

14.
Parasitol Res ; 104(5): 1053-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19085009

RESUMO

The current therapy for leishmaniasis, which affects annually about 2 million people, is far from satisfactory. All available drugs require parenteral administration and are potentially toxic. Plant essential oils have been traditionally used in folk medicine and appear as valuable alternative source for chemotherapeutic compounds. In this study, we demonstrated the effect of essential oils from Cymbopogon citratus, Lippia sidoides, and Ocimum gratissimum on growth and ultrastructure of Leishmania chagasi promastigote forms. Steam distillation was used to isolate the essential oils, and their constituents were characterized by gas chromatography coupled to mass spectrometry and nuclear magnetic resonance. All essential oils showed in vitro inhibitory action on L. chagasi promastigotes growth in a dose-dependent way, with IC(50)/72 h of 45, 89, and 75 microg/mL for C. citratus, L. sidoides, and O. gratissimum, respectively. Drastic morphological alterations were observed in all essential oil-treated parasites, including cell swelling, accumulation of lipid droplets in the cytoplasm, and increase of acidocalcisome volume. Furthermore, aberrant-shaped cells with multi-septate body were observed by scanning electron microscopy, suggesting an additional effect on cytokinesis. Taken together, our data show that these essential oils affect the parasite viability being the C. citratus essential oil the most effective against L. chagasi.


Assuntos
Cymbopogon/química , Leishmania infantum/efeitos dos fármacos , Lippia/química , Ocimum/química , Óleos Voláteis/isolamento & purificação , Animais , Tamanho Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinese/efeitos dos fármacos , Citoplasma/ultraestrutura , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Leishmania infantum/crescimento & desenvolvimento , Leishmania infantum/fisiologia , Leishmania infantum/ultraestrutura , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óleos Voláteis/química
15.
Am J Kidney Dis ; 47(4): 587-92, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16564936

RESUMO

BACKGROUND: Hypertension and increased left ventricular mass index (LVMI) have been reported in patients with early stages of autosomal dominant polycystic kidney disease (ADPKD). Whether these abnormalities are associated with diastolic dysfunction in this stage remains to be established. The aim of the study is to evaluate diastolic function in young normotensive patients with ADPKD by using tissue Doppler imaging (TDI), the most sensitive method available to date. METHODS: Thirty-two young clinically normotensive patients aged 21 to 30 years were compared with 23 controls with similar ages. Ambulatory blood pressure measurement (ABPM) was performed to confirm normal blood pressure. Subsequently, patients and controls underwent echocardiography using transmitral Doppler and TDI. RESULTS: LVMI was greater in patients with ADPKD than controls (89.3 +/- 17.7 versus 77.6 +/- 15.9 g/m2; P < 0.02). No significant differences were found in transmitral Doppler and TDI results. When ABPMs were taken into account, 11 patients had mild hypertension and showed increased LVMI and decreased early diastolic peak velocity (E wave: 67.0 +/- 12.0 cm/s in hypertensive patients with ADPKD versus 81.4 +/- 3.3 cm/s in normotensive patients with ADPKD versus 79.3 +/- 2.9 cm/s in controls; P < 0.04) and decreased TDI peak early diastolic annular velocity (11.6 +/- 2.8 cm/s in hypertensive patients with ADPKD versus 13.2 +/- 1.6 cm/s in normotensive patients with ADPKD versus 13.4 +/- 1.6 in controls; P < 0.05). CONCLUSION: Diastolic dysfunction is not a prominent sign in young normotensive patients with ADPKD.


Assuntos
Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/fisiopatologia , Ultrassonografia Doppler , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda , Adulto , Feminino , Seguimentos , Humanos , Masculino
16.
Arq. neuropsiquiatr ; 48(3): 320-8, set. 1990. ilus, tab
Artigo em Português | LILACS | ID: lil-85636

RESUMO

Potenciais evocados sensoriais (PES) säo analisados pelos autores, apoiados em experiência de mais de 6 anos. E conceituado o método, orientando a obtençäo à beira do letio, em UTI, em pacientes em coma. Analisa-se a execuçäo de PE visual por flash (PEV-F), PE auditivo de tronco cerebral (PEA-TC) e PE sômato-sensitivo de nervo mediano (PESS-M), prodondo-se classificaçäo dos achados principais. E discutido o valor diagnóstico dos PES em pacientes em coma, principalmente na avaliaçäo neurofisiológica do nível de comprometimento do sistema nervoso, cruzando-se informaçöes obtidas por via horizontal (PEV-F) vertical (PESS-M) e do tronco cerebral (PEA-TC). Os PES podem colaborar no diagnóstico de morte encefálica e na detecçäo de alteraçöes específicas a cada via. E ressaltado o valor prognóstico dos PES, em especial do PESS-M normal ou apenas levemente alterado indica bom prognóstico: PESS-M com ausência bilateral de componentes tálamo-corticais denuncia mau prognóstico. O PEV-F mostra comportamento similar ao do PESS-M


Assuntos
Humanos , Coma/fisiopatologia , Potenciais Evocados/fisiologia , Sistema Nervoso/fisiopatologia , Coma/diagnóstico , Potenciais Evocados Auditivos/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Potenciais Evocados Visuais/fisiologia , Prognóstico
17.
Temas (Säo Paulo) ; 17(32/33): 167-80, jun.-dez. 1987.
Artigo em Português | LILACS | ID: lil-69021

RESUMO

Os potenciais evocados sensoriais (PES) podem ser úteis para colaborar no diagnóstico diferencial entre distúrbios orgânicos acometendo vias do sistema nervoso e distúrbios psicogênicos como histeria e simulaçäo. Contudo, a utilidade diagnóstica do teste tem limitaçöes: certos déficitis neurológicos podem cursar com PES normais e está descrito que alguns indivíduos podem alterar voluntariamente as respostas do potencial evocado visual. Portanto, é importante ressaltar que os PES devem ser valorizados apenas junto ao contexto clínico e devem ser executados e interpretados dentro de normas técnicas bem estabelecidas


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Criança , Potenciais Evocados , Histeria/diagnóstico , Simulação de Doença/diagnóstico , Diagnóstico Diferencial
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