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1.
Phys Rev Lett ; 131(10): 102502, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739382

RESUMO

The absolute scale of the neutrino mass plays a critical role in physics at every scale, from the subatomic to the cosmological. Measurements of the tritium end-point spectrum have provided the most precise direct limit on the neutrino mass scale. In this Letter, we present advances by Project 8 to the cyclotron radiation emission spectroscopy (CRES) technique culminating in the first frequency-based neutrino mass limit. With only a cm^{3}-scale physical detection volume, a limit of m_{ß}<155 eV/c^{2} (152 eV/c^{2}) is extracted from the background-free measurement of the continuous tritium beta spectrum in a Bayesian (frequentist) analysis. Using ^{83m}Kr calibration data, a resolution of 1.66±0.19 eV (FWHM) is measured, the detector response model is validated, and the efficiency is characterized over the multi-keV tritium analysis window. These measurements establish the potential of CRES for a high-sensitivity next-generation direct neutrino mass experiment featuring low background and high resolution.

2.
Phys Rev Lett ; 130(20): 203603, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37267539

RESUMO

Control of the potential energy and free evolution lie at the heart of levitodynamics as key requirements for sensing, wave function expansion, and mechanical squeezing protocols. Here, we experimentally demonstrate versatile control over the optical potential governing the libration motion of a levitated anisotropic nanoparticle. This control is achieved by introducing the degree of polarization as a new tool for rotational levitodynamics. We demonstrate thermally driven free rotation of a levitated anisotropic scatterer around its short axis and we use the rotational degrees of freedom to probe the local spin of a strongly focused laser beam.

3.
Clin Hemorheol Microcirc ; 63(1): 77-87, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26484711

RESUMO

INTRODUCTION: The aim of this study was to analyze the histological subtypes of clear cell renal cell carcinoma (RCC) examined by means of contrast-enhanced ultrasound (CEUS) and a second generation blood pool agent (SonoVue®, Bracco, Milan, Italy) during the pre-operative phase. MATERIALS AND METHODS: 29 patients with histologically proven subtypes of clear cell RCC were examined. A total of three patients were diagnosed with highly differentiated clear cell RCC, 21 out of 29 cases with moderately differentiated clear cell RCC and five out of 29 patients had insufficiently differentiated clear cell RCC. An experienced radiologist examined the patients with CEUS. The following parameters were analyzed: maximum signal intensity (PEAK), time elapsed until PEAK is reached (MTT), local blood flow (RBF), area under the time intensity curve (AUC) and the signal intensity (SI) during the course of time. For the groups all comparisons are made based on healthy renal parenchyma. RESULTS: In the clear cell RCC significant differences (significance level p < 0.05) between cancerous tissue and the healthy renal parenchyma were noticed in all four parameters. Therefore, the clear cell RCC stands out due to its reduced blood volume. However, it reached the PEAK reading relatively rapidly and its signal intensity was always lower than that of the healthy renal parenchyma. In the arterial phase retarded absorption of the contrast agent was observed, followed by fast washing out of the contrast agent bubbles.In all three histological subgroups no significant differences were noticed in PEAK and SI. However, the diagrams showed the possible bias, that the group of the insufficiently differentiated clear cell RCC had the highest PEAK-value and the highest signal intensity when compared with highly and moderately differentiated clear cell RCC. CONCLUSION: Our study suggests that CEUS may be an additional tool for non-invasive characterisation and differentiation of the three histological subtypes of clear cell RCC. Furthermore, it seems to have an additional diagnostic value in daily clinical.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Meios de Contraste/uso terapêutico , Neoplasias Renais/diagnóstico por imagem , Idoso , Carcinoma de Células Renais/patologia , Humanos , Neoplasias Renais/patologia , Masculino
4.
Clin Hemorheol Microcirc ; 63(2): 89-97, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26484712

RESUMO

PURPOSE: The aim of this study was to analyse clear cell and papillary renal cell carcinoma (RCC) examined with contrast-enhanced ultrasound (CEUS) and a second generation blood pool agent (SonoVue®, Bracco, Milan, Italy) before clinical intervention. MATERIALS AND METHODS: A total of 41 patients with histologically proven subtypes of RCC were examined. 29 patients had a clear cell RCC and 12 patients showed a papillary RCC. Average size in the clear cell RCC group was 6.07 cm and 1.88 cm in the papillary RCC group. An experienced radiologist examined all patients with CEUS. The following parameters were analysed: maximum signal intensity (PEAK), time elapsed until PEAK is reached (MTT), local blood flow (RBF), area under the time intensity curve (AUC) and the signal intensity (SI) during the course of time. For both groups all comparisons were made based on healthy renal parenchyma. RESULTS: In the clear cell RCC significant differences (significance level p < 0.05) between cancerous tissue and the healthy renal parenchyma were noticed in all four parameters. The clear cell RCC showed a significant reduced blood volume. It reached the PEAK reading relatively rapidly and its signal intensity was always lower than that of the healthy renal parenchyma. In the arterial phase retarded absorption of the contrast agent was observed, followed by fast washing out of the contrast agent bubbles.In the papillary RCC group, significant findings as to PEAK and RBF as well as a slightly significant difference as to AUC were recorded. The papillary RCC had a lower blood supply and reached its PEAK reading later. Its signal intensity was also reduced. The signal intensity of papillary NCC was significantly lower compared with clear cell RCC; absorption and washing out of the contrast agent was delayed. CONCLUSION: CEUS seems to be an useful additional method to clinically differentiate between clear cell and papillary RCC. In daily clinical use, patients with contraindication for other imaging methods, especially the magnetic resonance imaging, might particularly benefit from this method.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Meios de Contraste/metabolismo , Neoplasias Renais/diagnóstico por imagem , Rim/patologia , Imageamento por Ressonância Magnética/métodos , Ultrassonografia/métodos , Adulto , Idoso , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade
5.
Clin Hemorheol Microcirc ; 63(2): 99-111, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26484713

RESUMO

PURPOSE: To compare the value of a portable ultrasound system and a high end ultrasound system in detection of endoleaks after EVAR. MATERIAL AND METHODS: In this retrospective study, a cohort of 25 patients underwent both standard examination using a portable ultrasound system (Philips VISIQ) and a second examination using a high end ultrasound system (Philips EPIQ 7). The examination included B-mode and color Doppler in detection of endoleaks. Additional the maximum diameter of the aneurysm was measured in two planes (right-left and ventral-dorsal). The gold standard was contrast-enhanced ultrasound (CEUS) in detection of endoleaks. RESULTS: 25 patients were included in the study. Patients were predominantly male (n = 23) with an average age of 73,30±7.82 years (range 54-85). Diameters of the treated aneurysms were in the right-left plane 5,32±1.88 cm and ventral-dorsal 4,99±1.78 cm using the high end system. Diameters of the treated aneurysms were in the right-left plane 5,30±1.82 cm and ventral-dorsal 4,87±1.74 cm using portable ultrasound system. In 80% of the cases CEUS could detect an endoleak. Whereas the high end system could detect in B-mode 40% and color Doppler 45% of the cases an endoleak. The portable system could detect in B-mode 30% and in color Doppler 35% of the cases an endoleak. On both systems in B-mode a false positive endoleak was found on the same patient. All high flow endoleaks, which needed intervention, could be detected on all systems. CONCLUSION: The high end ultrasound system does not seem to have an additional advantage in the measurement of the aneurysm diameter. Due to a higher resolution, more endoleaks could be detected in B-mode and color Doppler by using the high end system. The presence of small endoleaks could only be detected by using contrast enhanced ultrasound on an high end ultrasound system. High flow endoleaks could be reliable seen on both systems.


Assuntos
Meios de Contraste/uso terapêutico , Endoleak/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Mutat Res ; 558(1-2): 181-97, 2004 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-15036131

RESUMO

Nineteen coded chemicals were tested in an international collaborative study for their mutagenic activity. The assay system employed was the Ames II Mutagenicity Assay, using the tester strains TA98 and TAMix (TA7001-7006). The test compounds were selected from a published study with a large data set from the standard Ames plate-incorporation test. The following test compounds including matched pairs were investigated: cyclophoshamide, 2-naphthylamine, benzo(a)pyrene, pyrene, 2-acetylaminofluorene, 4,4'-methylene-bis(2-chloroaniline), 9,10-dimethylanthracene, anthracene, 4-nitroquinoline-N-oxide, diphenylnitrosamine, urethane, isopropyl-N(3-chlorophenyl)carbamate, benzidine, 3,3'-5,5'-tetramethylbenzidine, azoxybenzene, 3-aminotriazole, diethylstilbestrol, sucrose and methionine. The results of both assay systems were compared, and the inter-laboratory consistency of the Ames II test was assessed. Of the eight mutagens selected, six were correctly identified with the Ames II assay by all laboratories, one compound was judged positive by five of six investigators and one by four of six laboratories. All seven non-mutagenic samples were consistently negative in the Ames II assay. Of the four chemicals that gave inconsistent results in the traditional Ames test, three were uniformly classified as either positive or negative in the present study, whereas one compound gave equivocal results. A comparison of the test outcome of the different investigators resulted in an inter-laboratory consistency of 89.5%. Owing to the high concordance between the two test systems, and the low inter-laboratory variability in the Ames II assay results, the Ames II is an effective screening alternative to the standard Ames test, requiring less test material and labor.


Assuntos
Cooperação Internacional , Testes de Mutagenicidade/normas , Mutagênicos/toxicidade , Salmonella typhimurium/genética
7.
Orig Life Evol Biosph ; 29(3): 229-47, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10465714

RESUMO

Plausible prebiotic conditions for the phosphorylation of nucleosides by inorganic phosphate were reported by Lohrmann and Orgel in 1971. This reaction was carried out on heated dry films and promoted by urea. The major products formed were nucleoside-2:3 cyclicPs;5-NMPs and other derivatives were also formed. Minor modifications of the Lohrmann and Orgel system have resulted in the preferential formation of 5-NMPs. In this modified system a 2-fold preference for phosphorylation of the 5-OH group over the 3(2)-OH group was observed and the formation of other derivatives was minimized. The small amounts of bis compounds that were formed in this system could be quantitatively removed by selective binding to the mineral hydroxylapatite at moderate ionic strengths. It was also discovered that under hydrolytic conditions there was a 3:1 preference for removal of phosphates attached to the 3-OH group over the 5-OH group. A recycling procedure for obtaining additonal 5-NMPs from bis compounds and 3-NMPs is proposed.


Assuntos
Nucleosídeos/química , RNA/química , Adenosina/química , Cátions Bivalentes/química , Cromatografia , Citidina/química , Hidrólise , Inosina/química , Minerais/química , Compostos Organofosforados/química , Fosfatos/química , Fosforilação , Compostos de Amônio Quaternário/química , Ureia/química , Uridina/química
9.
Int J Neurosci ; 87(3-4): 113-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9003972

RESUMO

Brainstem auditory evoked potentials were recorded in a 3-year-old girl with the central alveolar hypoventilation syndrome (Ondine's syndrome). Abnormal findings were seen at the level of the mid to upper brain stem (wave III), which was not reproducibly recordable on the left side. This electrophysiologic abnormality is consistent with a previous finding in a patient with sleep apnea.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico , Síndromes da Apneia do Sono/fisiopatologia , Pré-Escolar , Dominância Cerebral , Feminino , Humanos , Tempo de Reação
10.
Ann Anat ; 178(4): 353-9, 1996 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-8928937

RESUMO

The disputed rotating function of certain muscles in the hip joint. A device constructed for that study allows to determine the rotating function of the iliopsoas muscle as well as of the uniarticular adductor muscles of the thigh in every position of the hip joint by the method of threads. The iliac muscle rotates the thigh inward in every position of flexion/extension or abduction/adduction of the hip joint. The adductor magnus muscle always is a lateral rotator by those fibres which are inserted into the medical edge of the linea aspera, while the fibres attached to the adductor tubercle rotate the thigh inward. The psoas major, pectineus, adductor longus and adductor brevis muscles are able to rotate the thigh inward as well as outward. Their rotating function depends on the specific position of flexion/extension and abduction/adduction of the hip joint: Flexion and abduction intensify the lateral rotating function of these muscles, extension and adduction intensify the medial rotating function.


Assuntos
Articulação do Quadril/fisiologia , Músculo Esquelético/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Articulação do Quadril/anatomia & histologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Movimento , Músculo Esquelético/anatomia & histologia , Rotação
11.
Hum Exp Toxicol ; 15(7): 556-62, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8818708

RESUMO

1. We are reporting investigations into the potential of the steroid hormones chlormadinone acetate (CMA), cyproterone acetate (CPA), ethinylestradiol (EE2) gestodene (GEST), megestrol acetate (MGA), norethisterone acetate (NET-Ac), estradiol (E2), and progesterone (P) to form DNA-adducts in rat liver in vivo. 2. Compound-related DNA-adduct spots were detected in male and female rat liver following CMA, CPA, and MGA using the 32P-postlabeling-technique. Substance-specific DNA-adducts were also observed in male rats after administration of E2. The other compounds showed no DNA-adduct formation. After treatment with CMA, CPA or MGA, the relative adduct labeling (RAL) differed sex- and substance-specifically.


Assuntos
Adutos de DNA/efeitos dos fármacos , Fígado/efeitos dos fármacos , Esteroides/toxicidade , Animais , DNA/efeitos dos fármacos , DNA/isolamento & purificação , Adutos de DNA/metabolismo , Dano ao DNA/fisiologia , Feminino , Fígado/metabolismo , Masculino , Radioisótopos de Fósforo , Ratos , Ratos Wistar , Caracteres Sexuais
12.
Int J Neurosci ; 84(1-4): 35-44, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8707486

RESUMO

Brainstem auditory evoked potentials (BAEPs) were recorded in 14 artificially ventilated patients (12 males, 2 females; mean age 33.3 +/- 16.3 years, range 18-67) with respiratory insufficiency resulting from severe inflammatory encephalopathies. The results were compared with those of 17 healthy volunteers (13 males, 4 females; mean age 27.4 +/- 5.3 years, range 21-45). BAEPs in the study patients showed prolonged interpeak latencies (I-III, I-V, III-V, IV-V) and delayed absolute latencies of waves I, II, III, and V at least on one side. Because the auditory pathways are in the near vicinity of the respiratory control centers in the brainstem, the electrophysiologic abnormalities of wave III and the IV/V complex may be a reflection of the disturbed central control of ventilation.


Assuntos
Encefalite/complicações , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Insuficiência Respiratória/fisiopatologia , Estimulação Acústica , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Respiratória/etiologia , Tomografia Computadorizada por Raios X
13.
Environ Mol Mutagen ; 28(2): 133-44, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8844995

RESUMO

The cytogenetic potential of 10 sex steroids (cyproterone acetate, drospirenone, gestodene, cyclodiol, cyclotriol, ethinylestradiol, atamestane, lilopristone, onapristone and propylmesterolone) with various medical indications was determined using the chromosomal aberration test in human lymphocytes in vitro and the mouse bone marrow micronucleus test in vivo. Nine of these sex steroids (gestodene was omitted) were investigated in the human lymphocyte assay and found to be negative with respect to the induction of chromosomal aberrations either with or without metabolic activation. In all assays the highest concentration evaluated was either clearly cytotoxic or, in case of noncytotoxicity, resulted in visible precipitates in the culture medium. Evaluation of the data from the mouse bone marrow micronucleus test indicated that the seven steroids (cyproterone acetate, drospirenone, gestodene, ethinylestradiol, atamestane, onapristone and propylmesterolone) investigated failed to induce enhanced frequencies of micronucleated polychromatic erythrocytes in male and female mice. The steroids were tested up to dose levels which induced signs of toxicity in the experimental animals or, in the case of non toxic compounds, the animals were treated up to the maximum recommended dose of 2 g/kg body weight. Evaluation of all data indicates that the investigated estrogens, progestins and other sex steroids had no genotoxic potential detectable with the chromosomal aberration assay on cultured human lymphocytes or the mouse bone marrow micronucleus test.


Assuntos
Medula Óssea/efeitos dos fármacos , Aberrações Cromossômicas , Hormônios Esteroides Gonadais/toxicidade , Animais , Células Cultivadas , Etinilestradiol/toxicidade , Feminino , Humanos , Linfócitos/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos , Testes para Micronúcleos/métodos , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Ratos , Ratos Sprague-Dawley , Ratos Wistar
15.
Environ Mol Mutagen ; 21(3): 272-304, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8462531

RESUMO

The mutagenicity results and data of nine progestins (cyproterone acetate, dehydrospirorenone, gestodene, gestonorone caproate, levonorgestrel, norethisterone, norethisterone acetate, norethisterone enanthate, norethynodrel), one hypothetical metabolite (6,7-epoxy-cyproterone acetate), four estrogens (estradiol, ethinylestradiol, cyclodiol, cyclotriol), and four other sex steroids (atamestane, lilopristone, onapristone, propylmesterolone) are reported. All 17 sex steroids were investigated using the Ames salmonella/microsome direct plate incorporation protocol, and seven were additionally tested using the preincubation modification. Seven sex steroids were also studied in the HG-PRT test with V79 cells for the induction of gene mutations in mammalian cells. The metabolite was examined in the Ames salmonella/microsome assay using the standard protocol and the preincubation modification. In all assays the test compounds were investigated up to concentration levels where cytotoxicity and/or visible precipitation occurred or at least the solubility limit of the test compound was reached. For all assays, evaluation of the data indicates that neither any of the sex steroids nor the hypothetical metabolite was able to induce gene mutations whether in the absence or the presence of an extrinsic metabolizing system (S9 mix).


Assuntos
Congêneres do Estradiol/toxicidade , Hormônios Esteroides Gonadais/toxicidade , Mutagênicos/toxicidade , Progestinas/toxicidade , Animais , Células Cultivadas , Cricetinae , Cricetulus , Acetato de Ciproterona/análogos & derivados , Compostos de Epóxi/toxicidade , Estradiol/toxicidade , Hipoxantina Fosforribosiltransferase/genética , Extratos Hepáticos , Microssomos/enzimologia , Testes de Mutagenicidade , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Esteroides/toxicidade
16.
Acta Anat (Basel) ; 144(1): 30-5, 1992.
Artigo em Alemão | MEDLINE | ID: mdl-1514356

RESUMO

90% of the first (hallucal) tarsometatarsal joints are screw-shaped; the axis is directed upwards to the front touching the lateral edge of the joint. Thus the plantar flexion is inevitably accompanied by an adduction and a pronation, and vice versa a dorsiflexion is consequently accompanied by an abduction and a supination, when the articular surfaces exactly slide along each other. 10% of these joints, however, are ellipsoid-shaped; in this case the distal articular surface of the medial cuneiform bone has the form of an ovoid head, and a strong ligament situated next to the lateral edge of the joint effects the same kind of motion described above. The medial cuneonavicular joint is always ellipsoid-shaped, the head of which is made up by the medial facet of the distal articular surface of the navicular bone. Each of the two joints mentioned has a considerable range of mobility.


Assuntos
Articulação Metatarsofalângica/anatomia & histologia , Movimento/fisiologia , Articulação do Dedo do Pé/anatomia & histologia , Fenômenos Biomecânicos , Osso e Ossos/anatomia & histologia , Osso e Ossos/fisiologia , Humanos , Articulação Metatarsofalângica/fisiologia , Modelos Biológicos , Articulação do Dedo do Pé/fisiologia , Dedos do Pé
17.
Acta Anat (Basel) ; 140(4): 319-28, 1991.
Artigo em Alemão | MEDLINE | ID: mdl-1927243

RESUMO

By the manual test of the lumbosacral instability described by Eder and Tilscher we can never find out for certain whether the fifth lumbar vertebra can be shifted ventrally above the sacrum. Before this test the patient has to be turned over on to his side with hips flexed, which causes a ventral flexion (anteflexion) of the lumbosacral segment. During the test, however, the lumbosacral segment is forced to a dorsal flexion (retroflexion); therefore the spinous process of the fifth lumbar vertebra retires from the back surface simulating a sliding forward of the whole vertebra.


Assuntos
Vértebras Lombares/fisiopatologia , Sacro/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vértebras Lombares/anatomia & histologia , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Postura , Radiografia , Sacro/anatomia & histologia , Sacro/diagnóstico por imagem
20.
Gegenbaurs Morphol Jahrb ; 136(4): 443-54, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2242822

RESUMO

Variants shown by the orientation of the cover-plate and of the superior articular facets of the sacrum have a considerable influence on the lumbosacral biostatistics. This can be illustrated by parallelograms of forces. If we assume a certain force stressing upon the sacrum, we are able to calculate the distribution of stress upon the cover-plate and the articular facets by help of the size and the orientation of these weight bearing faces.


Assuntos
Vértebras Lombares/anatomia & histologia , Região Lombossacral/fisiologia , Sacro/anatomia & histologia , Humanos , Matemática
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