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1.
Phys Rev Lett ; 120(5): 052503, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29481181

RESUMO

In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods in order to test to what extent the chiral effective field theory framework impacts our knowledge of few- and many-body systems. In this Letter, we present Green's function Monte Carlo calculations of light nuclei based on the family of local two-body interactions presented by our group in a previous paper in conjunction with chiral three-body interactions fitted to bound- and scattering-state observables in the three-nucleon sector. These interactions include Δ intermediate states in their two-pion-exchange components. We obtain predictions for the energy levels and level ordering of nuclei in the mass range A=4-12, accurate to ≤2% of the binding energy, in very satisfactory agreement with experimental data.

2.
Acta Otorhinolaryngol Ital ; 37(2): 168-171, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28516981

RESUMO

Botulinum toxin (BTX) is a neurotoxic protein produced by Clostridium botulinum, an anaerobic bacterium. BTX therapy is a safe and effective treatment when used for functional silencing of the salivary glands in disorders such as sialoceles and salivary fistulae that may have a post-traumatic or post-operative origin. BTX injections can be considered in sialoceles and salivary fistulae after the failure of or together with conservative treatments (e.g. antibiotics, pressure dressings, or serial aspirations). BTX treatment has a promising role in chronic sialadenitis. BTX therapy is highly successful in the treatment of gustatory sweating (Frey's syndrome), and could be considered the gold standard treatment for this neurological disorder.


Assuntos
Toxinas Botulínicas/uso terapêutico , Neurotoxinas/uso terapêutico , Doenças das Glândulas Salivares/tratamento farmacológico , Humanos , Sudorese Gustativa/tratamento farmacológico
3.
Phys Rev Lett ; 117(8): 082501, 2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27588850

RESUMO

The longitudinal and transverse electromagnetic response functions of ^{12}C are computed in a "first-principles" Green's function Monte Carlo calculation, based on realistic two- and three-nucleon interactions and associated one- and two-body currents. We find excellent agreement between theory and experiment and, in particular, no evidence for the quenching of the measured versus calculated longitudinal response. This is further corroborated by a reanalysis of the Coulomb sum rule, in which the contributions from the low-lying J^{π}=2^{+}, 0_{2}^{+} (Hoyle), and 4^{+} states in ^{12}C are accounted for explicitly in evaluating the total inelastic strength.

6.
Phys Rev Lett ; 112(18): 182502, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24856692

RESUMO

An ab initio calculation of the sum rules of the neutral weak response functions in 12C is reported, based on a realistic Hamiltonian, including two- and three-nucleon potentials, and on realistic currents, consisting of one- and two-body terms. We find that the sum rules of the response functions associated with the longitudinal and transverse components of the (spacelike) neutral current are largest and that a significant portion (≃30%) of the calculated strength is due to two-body terms. This fact may have implications for the MiniBooNE and other neutrino quasielastic scattering data on nuclei.

7.
Int J Audiol ; 53(9): 625-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24735015

RESUMO

OBJECTIVE: Factor V Leiden (FVL) is by far the most prevalent inherited thrombophilic abnormality in Western countries, and this genetic condition has been associated with sudden sensorineural hearing loss (SSHL). Audiologists should be aware that SSHL may be the precursor of life-threatening thromboembolic events, especially in Caucasians who are more likely to be FVL carriers. DESIGN: Case report. STUDY SAMPLE: A 41-year-old male patient. RESULTS: Although this is not the first report of SSHL in a FVL carrier, it is the first to describe SSHL occurring in a heterozygous FVL carrier who--within a month--was also diagnosed with deep vein thrombosis of the left common femoral, saphenous, and popliteal veins, and pulmonary embolism of the left pulmonary artery branch serving the posterior basal segment of the inferior lobe. CONCLUSIONS: SSHL is an emergency condition that warrants prompt medical examination and treatment. Hematological investigations should be considered in SSHL patients at least for those with a family history of thrombotic events, and for women on estrogen-progestin therapy or during pregnancy, with a view to providing adequate antithrombotic prophylaxis and reducing the risk of other thromboembolic events.


Assuntos
Resistência à Proteína C Ativada/complicações , Fator V/genética , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Súbita/etiologia , Mutação , Embolia Pulmonar/etiologia , Trombose Venosa/etiologia , Resistência à Proteína C Ativada/diagnóstico , Resistência à Proteína C Ativada/genética , Adulto , Anticoagulantes/uso terapêutico , Análise Mutacional de DNA , Predisposição Genética para Doença , Glucocorticoides/uso terapêutico , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Súbita/diagnóstico , Perda Auditiva Súbita/tratamento farmacológico , Heterozigoto , Humanos , Masculino , Fenótipo , Valor Preditivo dos Testes , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamento farmacológico , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Trombose Venosa/diagnóstico , Trombose Venosa/tratamento farmacológico
8.
Eur Arch Otorhinolaryngol ; 271(4): 757-64, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24065188

RESUMO

Epidermal growth factor receptor (EGFR) is a trans-membrane tyrosine kinase taking part in cell transformation and tumor progression. One of the downstream pathways controlled by EGFR involves the mammalian target of rapamycin (mTOR), a proto-oncogene activated in several cell functions. Recent evidence seems to confirm that both EGFR and mTOR regulate angiogenesis. The aim of this study was to investigate the expression of EGFR and mTOR in laryngeal squamous cell carcinoma (LSCC) cells in a retrospective clinical setting and their correlation with tumor neo-angiogenesis, judged on the grounds of CD105-assessed microvascular density (MVD), and prognosis. We considered 76 consecutive patients with LSCC treated with surgery alone. Immunohistochemical expressions of EGFR, mTOR, and CD105 were measured using image analysis and findings underwent statistical analysis using univariate and multivariate models. We found that nodal status correlated significantly with patient prognosis in terms of disease-free survival (DFS) (p = 0.01). There was a strong direct correlation between mTOR and EGFR expression (p = 0.0003), and between mTOR and CD105-assessed MVD (p = 0.0025). Patients with a CD105-assessed MVD >5.28 % had a significantly higher recurrence rate (RR) (p = 0.026), and a significantly shorter DFS (p = 0.025). On multivariate analysis, only N stage [hazard ratio (HR) 3.54, p = 0.009] and CD105-assessed MVD (HR 2.87, p = 0.027) maintained their independent prognostic significance in terms of DFS. Judging from our promising findings, the EGFR-mTOR pathway should be investigated further to understand its role in LSCC neo-angiogenesis.


Assuntos
Antígenos CD/metabolismo , Carcinoma de Células Escamosas/metabolismo , Receptores ErbB/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias Laríngeas/metabolismo , Neovascularização Patológica/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Intervalo Livre de Doença , Endoglina , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Prognóstico , Proto-Oncogene Mas , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
9.
Phys Rev Lett ; 111(9): 092501, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-24033027

RESUMO

An ab initio calculation of the 12C elastic form factor and sum rules of longitudinal and transverse response functions measured in inclusive (e, e') scattering are reported, based on realistic nuclear potentials and electromagnetic currents. The longitudinal elastic form factor and sum rule are found to be in satisfactory agreement with available experimental data. A direct comparison between theory and experiment is difficult for the transverse sum rule. However, it is shown that the calculated transverse sum rule has large contributions from two-body currents, indicating that these mechanisms lead to a significant enhancement of the quasielastic transverse response. This fact may have implications for the anomaly observed in recent neutrino quasielastic charge-changing scattering experiments on 12C.

10.
Am J Ophthalmol ; 110(3): 233-6, 1990 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-2204269

RESUMO

We studied the accuracy of B-scan ultrasonography to diagnose radiation-induced optic neuropathy in 15 patients with uveal melanoma. Optic neuropathy was diagnosed by an observer masked as to clinical and photographic data. We analyzed planimetry area measurements of the retrobulbar nerve before and after irradiation. The retrobulbar area of the optic nerve shadow on B-scan was quantitated with a sonic digitizer. Increased optic nerve shadow area was confirmed in 13 of 15 patients who had radiation optic neuropathy (P less than .004). The correct diagnosis was confirmed when the results of ultrasound were compared to fundus photography and fluorescein angiography. In 13 patients there was acute radiation optic neuropathy. Two patients did not show an enlarged retrobulbar optic nerve, and the clinical appearance suggested early progression to optic atrophy. Ultrasonography documents the enlargement of the optic nerve caused by acute radiation changes.


Assuntos
Doenças do Nervo Óptico/etiologia , Lesões por Radiação , Ultrassonografia/métodos , Doença Aguda , Neoplasias Oculares/radioterapia , Angiofluoresceinografia , Fundo de Olho , Humanos , Doenças do Nervo Óptico/diagnóstico , Fotografação
11.
Invest Ophthalmol Vis Sci ; 31(9): 1745-53, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2211022

RESUMO

Scleral surface coils were used to obtain in vivo magnetic resonance spectra (MRS) of Greene melanoma implanted in the rabbit uvea. Well-localized tumor spectra (4.7 Tesla) with good signal-to-noise ratios (S/N) were obtained from the tumor with a "single-pulse" sequence in less than 1 hour. Tumor localization was confirmed with one-dimensional spectroscopic imaging studies. Serial 31P spectra were obtained during tumor growth and after both optimal and suboptimal hyperthermia. Early 31P MRS change is correlated with tumor treatment response and preceded histologic evidence of cell destruction. Twenty-four to 48 hours after successful treatment, the inorganic phosphate/nucleoside triphosphate (NTP), and phosphomonoester/NTP ratios were significantly increased from 1.2 +/- 0.1 to 1.7 +/- 0.1 and 1.3 +/- 0.1 to 1.8 +/- 0.2, respectively. In contrast, untreated or ineffectively treated tumors showed little change. Interpretation of 31P MRS data in this animal uveal melanoma model after the first week was complicated by decreased S/N, increased contamination from contiguous tissues, ingrowth of fibroblasts, macrophages, and intratumor hemorrhage.


Assuntos
Hipertermia Induzida , Espectroscopia de Ressonância Magnética , Melanoma Experimental/fisiopatologia , Neoplasias Uveais/fisiopatologia , Animais , Masculino , Melanoma Experimental/terapia , Coelhos , Neoplasias Uveais/terapia
12.
Am J Ophthalmol ; 108(6): 712-6, 1989 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2596553

RESUMO

We analyzed the number of cycling cells in the DNA synthesis phase and in mitosis in two uveal melanomas unsuccessfully treated with iodine 125 brachytherapy. In one patient, the tumor appeared to have been radioresistant, whereas the other patient had a clinically inapparent area of tumor that was not included in the tumoricidal radiation field. In the first patient, there was uniform tumor cell cycling, whereas the second patient had cycling cells predominantly in the area that did not receive optimal radiation. This gradient of cycling tumor cells in the second patient was observed with both standard histologic examination (mitoses per high-powered field) and bromodeoxyuridine staining (DNA synthesis). The bromodeoxyuridine technique was significantly more sensitive than standard histologic examination in the detection of cycling cells.


Assuntos
Braquiterapia , Neoplasias da Coroide/radioterapia , DNA de Neoplasias/biossíntese , Melanoma/radioterapia , Recidiva Local de Neoplasia , Neoplasias Uveais/radioterapia , Idoso , Bromodesoxiuridina , Neoplasias da Coroide/genética , DNA de Neoplasias/efeitos da radiação , Enucleação Ocular , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Mitose/efeitos da radiação , Neoplasias Uveais/genética
13.
Am J Ophthalmol ; 108(4): 431-4, 1989 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-2801862

RESUMO

We evaluated prophylactic silicone tube intubation of the nasolacrimal drainage system prior to helium ion irradiation of uveal melanomas located on the nasal side of the globe. Twelve patients received silicone tubes and were compared to a control group of 12 patients with irradiated nasal tumors without silicone tubes. Symptoms of nasolacrimal duct obstruction and epiphora were evaluated by means of a questionnaire. All patients had nasolacrimal duct irrigation. Patients intubated before irradiation maintained patency (11 of 12), whereas those in the control group did not (zero of 12) (P less than .0014); ten of 12 control patients had closure of both superior and inferior puncta. No significant difference in symptoms of epiphora was observed between the two groups.


Assuntos
Intubação , Doenças do Aparelho Lacrimal/etiologia , Aparelho Lacrimal , Melanoma/radioterapia , Ducto Nasolacrimal , Lesões por Radiação , Neoplasias Uveais/radioterapia , Hélio/uso terapêutico , Humanos , Intubação/efeitos adversos , Doenças do Aparelho Lacrimal/prevenção & controle , Radioisótopos/uso terapêutico , Silicones
14.
Boll Soc Ital Biol Sper ; 55(2): 153-8, 1979 Jan 30.
Artigo em Italiano | MEDLINE | ID: mdl-17955641

RESUMO

The effect of desoxycorticosterone on the adrenaline-induced relaxation of coronary arteries was studied in vitro, after a known inhibitor of COMT, pyrogallol. Relaxation induced by adrenaline was enhanced by desoxycorticosterone. Relaxation in response to adrenaline was increased by desoxycorticosterone. Pyrogallol potentiated the responses of coronary strips to adrenaline and also reduced or abolished the enhancing effects of desoxycorticosterone. It is concluded that desoxycorticosterone enhances the response of coronary smooth muscle to adrenaline by inhibiting an enzymatic pathway for the inactivation of catecholamines.


Assuntos
Antioxidantes/farmacologia , Vasos Coronários/efeitos dos fármacos , Desoxicorticosterona/farmacologia , Epinefrina/farmacologia , Mineralocorticoides/farmacologia , Pirogalol/farmacologia , Vasoconstritores/farmacologia , Animais , Bovinos , Quimioterapia Combinada , Técnicas In Vitro , Relaxamento Muscular/efeitos dos fármacos
15.
Boll Soc Ital Biol Sper ; 55(2): 159-62, 1979 Jan 30.
Artigo em Italiano | MEDLINE | ID: mdl-17955642

RESUMO

The effect of desoxycorticosterone on the adrenaline-induced relaxation of coronary arteries was studied "in vitro". It resulted that the effect of adrenaline was enhanced by desoxycorticosterone. It is concluded that desoxycorticosterone potentiates the effects of adrenaline by inhibiting its inactivation by Catechol-O-methyltransferase.


Assuntos
Vasos Coronários/efeitos dos fármacos , Desoxicorticosterona/farmacologia , Epinefrina/farmacologia , Mineralocorticoides/farmacologia , Vasoconstritores/farmacologia , Animais , Bovinos , Técnicas In Vitro , Relaxamento Muscular/efeitos dos fármacos
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