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1.
Clin Radiol ; 71(6): 615.e1-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27005016

RESUMO

AIM: To assess image quality and radiation dose in patients with body weights ≤75 kg undergoing abdominal computed tomography (CT) with a tube voltage of either 120 or 100 kVp. MATERIALS AND METHODS: Eighty patients weighing ≤75 kg were prospectively assigned to receive either 120 or 100 kVp abdominal CT in the portal-venous phase. Attenuation values of abdominal organs and image noise were measured, and the contrast-to-noise ratios (CNRs) were calculated. Subjective image quality was assessed by three independent radiologists. Radiation exposure was assessed by size-specific dose estimate (SSDE). RESULTS: The mean attenuation of the kidney increased by 20% at 100 kVp (p<0.0001), and the mean image noise was 27% higher in the 100 kVp (p=0.003). The CNR did not significantly differ between the groups (120 kVp, 6.6±2.8; 100 kVp, 7.4±3.6; p=0.26). Except for subjective image noise (p<0.001), no other subjective quality parameters (e.g., contrast, artefacts) were significantly different between the two groups (p between 0.094 and 0.761). The mean SSDE in the 100-kVp group (9.8±1.8 mGy) was reduced by 19% compared to the 120-kVp group (12.1±1.8 mGy; p<0.0001). CONCLUSION: Manual reduction of tube voltage from the standard 120 to 100 kVp for portal-venous phase CT in patients with body weights ≤75 kg resulted in a 19% dose reduction while maintaining objective and subjective image quality.


Assuntos
Peso Corporal , Tomografia Computadorizada Multidetectores/métodos , Doses de Radiação , Proteção Radiológica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Abdominal/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
AJNR Am J Neuroradiol ; 36(3): 562-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25395658

RESUMO

BACKGROUND AND PURPOSE: Physiologic and pathologic arterial tortuosity may attenuate blood flow pulsatility. The aim of this prospective study was to assess a potential effect of the curved V3 segment (Atlas slope) of the vertebral artery on arterial flow pulsatility. The pulsatility index and resistance index were used to assess blood flow pulsatility. MATERIALS AND METHODS: Twenty-one healthy volunteers (17 men, 4 women; mean age, 32 years) were examined with a 3T MR imaging system. Blood velocities were measured at 2 locations below (I and II) and at 1 location above the V3 segment (III) of the vertebral artery by using a high-resolution 2D-phase-contrast sequence with multidirectional velocity-encoding. RESULTS: Pulsatility and resistance indices decreased along all measurement locations from proximal to distal. The pulsatility index decreased significantly from location II to III and from I to II. However, the decrease was more pronounced along the Atlas slope than in the straight-vessel section below. The decrease of the resistance index was highly significant along the Atlas slope (location II to III). The decrease from location I to II was small and not significant. CONCLUSIONS: The pronounced decrease in pulsatility and resistance indices along the interindividually uniformly bent V3 segment compared with a straight segment of the vertebral artery indicates a physiologic attenuating effect of the Atlas slope on arterial flow pulsatility. A similar effect has been described for the carotid siphon. A physiologic reduction of pulsatility in brain-supplying arteries would be in accordance with several recent publications reporting a correlation of increased arterial flow pulsatility with leukoencephalopathy and lacunar stroke.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Angiografia por Ressonância Magnética , Fluxo Pulsátil/fisiologia , Artéria Vertebral/fisiologia , Adulto , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Estudos Prospectivos , Resistência Vascular , Adulto Jovem
3.
Transplant Proc ; 46(7): 2360-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25242788

RESUMO

Wilson's disease (WD) is an autosomal recessive disorder characterized by copper overload. In this disease, inadequate hepatic excretion leads to copper accumulation in the liver, brain, kidney, and cornea. Severe neurological symptoms can develop in patients with WD, often in the absence of relevant liver damage: it is unclear whether liver transplantation (LT) could reverse neurological symptoms, and at present LT is not recommended in this setting. We report a case of regression of neurological symptoms in a patient affected by WD with prevalent neurological involvement. A 19-year-old man with disabling neuropsychiatric symptoms from WD that included frontal ataxia, akinesia, dystonia, tremors, and behavioral disorders in the presence of preserved liver function (Model for End-Stage Liver Disease score=7; Child-Turcotte-Pugh score=A5) underwent LT in November 2009. At the time of LT, encephalic magnetic resonance imaging (MRI) indicated diffuse neurodegenerative alterations involving subtentorial and supratentorial structures; bilateral Kayser-Fleischer ring was present. Four years after LT, laboratory tests show normalized copper metabolism and excellent liver function test results. Encephalic MRI shows a substantial improvement of already-known signal alterations at nuclei thalamus and putamen, mesencephalon, and pons. Kayser-Fleischer ring disappeared from the right eye, but a little remnant is still visible in the left eye. At neurological examination, all of the previous symptoms and signs are no longer present and behavioral disorders are no longer present; psychosocial functions are completely restored. The present case provides some evidence that LT may be a valid therapeutic option for WD patients with marked neurological impairment, particularly in those no longer responsive to chelation therapy.


Assuntos
Degeneração Hepatolenticular/cirurgia , Transplante de Fígado , Ceruloplasmina/análise , Cobre/sangue , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/diagnóstico , Humanos , Rim/patologia , Testes de Função Hepática , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
4.
Eur J Ophthalmol ; 17(5): 817-22, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17932861

RESUMO

PURPOSE: This study identifies the incidence of primary ocular pathologies in a population of Italian children with Down syndrome. METHODS: A total of 157 Italian children with Down syndrome, age between 1 month and 18 years, were screened between February 2005 and October 2006. The ophthalmologic evaluation included a global inspection of orbit and bulbus oculi, evaluation of ocular motility and visual acuity, slit lamp biomicroscopy, cycloplegic skiascopy, tonometry, and indirect ophthalmoscopy. RESULTS: The overall incidence of ocular abnormalities was epicanthal fold (132 patients, 84%), hyperopia (93 patients, 59%), astigmatism (44 patients, 28%), myopia (14 patients, 9%), strabismus (56 patients, 36%, 45 cases of esotropia and 11 cases of exotropia), congenital nasolacrimal duct obstruction (35 patients, 22%), cataract (18 patients, 11%), nystagmus (9 patients, 6%), blepharitis and conjunctivitis (6 patients, 4%), and retinal anomalies (10 patients, 6%). Unlike previous reports in patients with Down syndrome, no congenital glaucoma, keratoconus, or Brushfield spots were observed. CONCLUSIONS: Compared to other studies in patients with Down syndrome, we observed a higher incidence of hyperopia and a lower incidence of myopia. The incidence of nystagmus, blepharitis,and conjunctivitis was less than that reported in other studies, while strabismus, especially exotropia (20%), had a high incidence in our cohort. We also frequently observed obstruction of the nasolacrimal duct (22%), but no keratoconus or glaucoma.


Assuntos
Síndrome de Down/complicações , Oftalmopatias/epidemiologia , Adolescente , Criança , Pré-Escolar , Oftalmopatias/complicações , Feminino , Humanos , Incidência , Lactente , Itália/epidemiologia , Masculino , Estudos Retrospectivos
5.
J Inherit Metab Dis ; 27(2): 115-25, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15159642

RESUMO

Executive functions were studied in 14 early and continuously treated PKU subjects (age 10.8 years, range 8-13) in comparison with controls matched for IQ, sex, age and socioeconomic status. Brain MRI examination was normal in all PKU patients. Neuropsychological evaluation included Wisconsin Card Sorting Test, Rey-Osterreith Complex Figure Test, Elithorn's Perceptual Maze Test, Weigl's Sorting Test, Tower of London, Visual Search and Motor Motor Learning Test. Whatever the IQ, PKU subjects performed worse than controls in tests exploring executive functions. Subgrouping the PKU subjects according to the quality of dietary control for the entire follow-up period (using 400 micromol/L as cut-off value for blood phenylalanine (Phe) concentration) showed that patients with worse dietary control performed more poorly than both the PKU group with the best dietary control and the control group. However, a mild impairment of executive functions was still found in PKU patients with a good dietary control (Phe <400 micromol/L) compared to controls. Concerning the PKU group as a whole, no linear correlation was found between neuropsychological performance and historical and concurrent biochemical parameters. We conclude that (a) PKU patients, even when treated early, rigorously and continuously, show an impairment of frontal lobe functions; (b) a protracted exposure to moderately high levels of Phe can affect frontal lobe functions independently of the possible effect of the same exposure on IQ; (c) in order to reduce the risk of frontal lobe dysfunction, the target of dietary therapy should be to maintain blood Phe concentration below 400 micromol/L.


Assuntos
Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Lobo Frontal/fisiopatologia , Fenilcetonúrias/complicações , Fenilcetonúrias/fisiopatologia , Adolescente , Criança , Transtornos Cognitivos/diagnóstico , Feminino , Lobo Frontal/crescimento & desenvolvimento , Humanos , Inteligência , Masculino , Testes Neuropsicológicos , Fenilcetonúrias/dietoterapia , Prognóstico , Classe Social
6.
Hum Reprod ; 17(9): 2435-8, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12202437

RESUMO

BACKGROUND: The aim of this study was to evaluate treatment efficacy and patient acceptability of a new bipolar probe used during office hysteroscopic treatment of benign intrauterine pathologies. METHODS: In this observational clinical study, 501 women were treated for benign intrauterine pathologies using an office hysteroscopic procedure, without analgesia or anaesthesia. A Versapoint 5 Fr. bipolar electrical generator was used to treat endometrial polyps ranging between 0.5 and 4.5 cm, as well as submucosal and partially intramural myomas between 0.6 and 2.0 cm. Treatment efficacy and patient compliance were evaluated. RESULTS: At follow-up, the uterine cavity was normal in all patients without any recurrence or persistence of the pathology. One focal adenocarcinoma was discovered at histology in an endometrial polyp of a menopausal patient. Patient acceptance was satisfactory; 47.6-79.3% of the patients underwent the procedure without discomfort. CONCLUSIONS: The combination of a new generation small diameter hysteroscope and a new bipolar 5 Fr. electrode enables the gynaecologist to treat intrauterine pathologies in an office setting without anaesthesia. Experimentation of a special set-up of the electrical generator reduced patient discomfort during the operative part of the hysteroscopic procedure.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Anestesia , Histeroscópios , Histeroscopia , Neoplasias Uterinas/cirurgia , Adulto , Idoso , Eletrodos , Neoplasias do Endométrio/cirurgia , Desenho de Equipamento , Feminino , Humanos , Leiomioma/cirurgia , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Satisfação do Paciente , Pólipos/cirurgia , Resultado do Tratamento
7.
J Am Assoc Gynecol Laparosc ; 9(3): 290-2, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12101324

RESUMO

STUDY OBJECTIVE: To evaluate the quantity of biopsy tissue obtained by hysteroscopic grasp technique compared with classic punch technique. DESIGN: Observational study (Canadian Task Force classification II-2). SETTING: University hospital. PATIENTS: One thousand two hundred seventy-six women. INTERVENTION: Targeted biopsies performed in an office setting using two biopsy forceps, classic spoon and crocodile, and two methods, classic punch and grasp technique. MEASUREMENTS AND MAIN RESULTS: With either biopsy forceps, the mean increase in amount of tissue obtained by grasp technique compared with punch technique was statistically significant (p <0.005). With grasp technique, the mean amount of tissue obtained was even larger with crocodile than with spoon forceps. CONCLUSION: Targeted biopsy, when performed with the appropriate instrument and applying correct technique, can provide the pathologist with a large amount of tissue (mean 5.7 mm2) that is invariably adequate for histologic examination.


Assuntos
Endométrio/patologia , Histeroscópios , Histeroscopia , Manejo de Espécimes/instrumentação , Doenças Uterinas/patologia , Desenho de Equipamento , Feminino , Humanos , Manejo de Espécimes/métodos
8.
J Nat Prod ; 63(2): 263-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10691724

RESUMO

A detailed analysis of the secondary metabolites of the Caribbean sponge Verongula gigantea has been performed. A number of bromotyrosine derivatives, 1, 2, and 6-17, were identified, one of which (17) is a novel compound. Its structure was determined on the basis of spectroscopic evidence. Additionally, aureol (18) and 5, 6-dibromo-N,N-dimethyltryptamine (19) were isolated from one of the five analyzed specimens.


Assuntos
Poríferos/química , Animais , Cromatografia Líquida de Alta Pressão , Poríferos/metabolismo , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
9.
Minerva Ginecol ; 51(9): 313-7, 1999 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-10575897

RESUMO

BACKGROUND: To assess the value of intra-tumoral (endometrial) flow as detected by color Doppler ultrasound in relationship with negative prognostic factors in patients with endometrial carcinoma. METHODS: Fifty-three patients with a previous histological diagnosis of endometrial carcinoma were included in the study. Transvaginal ultrasound with pulsed color Doppler was performed in order to record resistance indexes and vascular density (defined as "high" if > or = 3 vascular spaces were detectable for any given area). All cases were classified according to FIGO after surgery and histology. Prognostic bad factors were considered: FIGO stage (> I), tumor grade (> 1), myometrial invasion (> 50%) involvement of vascular spaces and lymph node metastasis. RESULTS: Both resistance indexes and vascular density in the endometrium related well to more prognostic signs. No relationship was found for lymph node metastasis, probably justified by the small number of positive nodes (2/27). DISCUSSION: Color Doppler ultrasound seems to be a promising technique in pre-surgical staging of endometrial carcinoma. Detection of vascular spaces rather than low resistance indexes is, in personal experience, more significantly related to advanced disease. It is hypothesized that long term follow-up of these patients can show a predictive value of Doppler ultrasound on the outcome of the disease.


Assuntos
Neoplasias do Endométrio/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/irrigação sanguínea , Neoplasias do Endométrio/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Reologia , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler de Pulso
10.
J Nat Prod ; 62(4): 590-3, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10217716

RESUMO

A detailed analysis of the secondary metabolites of the sponge Aplysina cauliformis has been performed. Eight compounds were identified, two of which (13 and 14) are new bromotyrosine derivatives whose structures were determinated from spectroscopic evidence, including 2D NMR. The new compounds were analyzed for cytotoxic activity, and compound 14 was shown to inhibit mammalian protein synthesis and cell proliferation.

11.
Steroids ; 60(11): 768-72, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8585101

RESUMO

The sterol composition of the Caribbean sponge Neofibularia nolitangere has been investigated. In addition to usual sterols this sponge elaborates comparable amounts of 24-methylene-4 alpha-methyl-5 alpha-cholest-8-en-3 beta-ol (1), which is very unusual among sponge sterols, and lesser quantities of two new polyoxygenated sterols, (24S)-24-ethyl-5 alpha-cholest-8-ene-5,6 beta,7 alpha-triol (2) and (24S)-24-ethyl-5 alpha-cholest-8(14)-ene-5,6 beta,7 alpha-triol (3).


Assuntos
Poríferos/química , Esteróis/química , Animais , Colestenos/química , Colestenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Hidroxiesteroides/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Esteróis/isolamento & purificação
12.
J Nat Prod ; 55(9): 1275-80, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1431945

RESUMO

In addition to the known 3-hydroxydocosa-(4E, 15E)-dien-1-yne [1], 3-hydroxy-16-methyleicos-(4E)-en-1-yne [2], and 3-hydroxy-19-methyleicos-(4E)-en-1-yne [3], the lipophilic extract of the Caribbean sponge Cribrochalina vasculum was shown to contain four new bioactive acetylene metabolites, (3R)-hydroxy-14-methyldocos-(4E)-en-1-yne [4], (3R)-hydroxy-16-methyleicos-1-yne [7], (3R)-hydroxy-19-methyleicos-1-yne [8], and docosa-(3E, 15Z)-dien-1-yne [9], whose structures were elucidated on the basis of chemical and spectral studies. The previously unassigned chirality at C-3 of the known compounds 1-3 has been also established as R.


Assuntos
Acetileno/isolamento & purificação , Artemia/fisiologia , Poríferos/química , Acetileno/química , Acetileno/toxicidade , Animais , Bahamas , Belize , Espectroscopia de Ressonância Magnética , Oxirredução
13.
J Nat Prod ; 55(9): 1287-93, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1431947

RESUMO

Four new oxygenated diterpenes 1-4 were isolated from the Caribbean sponge Myrmekioderma styx. The structures of these compounds were deduced by ms, uv, ir, 1H- and 13C-nmr, 1H-1H COSY, XHCORR, and COLOC experiments. Compounds 1-4 are lethal to brine shrimp (Artemia salina).


Assuntos
Artemia/fisiologia , Diterpenos/isolamento & purificação , Poríferos/química , Animais , Diterpenos/toxicidade , Dose Letal Mediana , Espectroscopia de Ressonância Magnética , Índias Ocidentais
14.
Steroids ; 57(2): 62-6, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1621257

RESUMO

Three novel sterols with a rare D-ring unsaturation were isolated from the marine sponge Topsentia aurantiaca and identified as 5 alpha-cholest-14-ene-3 beta,16 alpha-diol (2), 24R-ethyl-5 alpha-cholest-14-ene-3 beta,16 alpha-diol (3), and 24S-ethyl-5 alpha-cholest-14-ene-3 beta,16 alpha-diol (4). The sponge also elaborates a further D-ring unsaturated sterol, 5 alpha-cholest-15-en-3 beta-ol (1), which has been previously described only as a synthetic product. All the 1H and 13C nuclear magnetic resonances of compounds 1 and 2 were assigned to the relevant protons and carbons by bidimensional COSY, HETCOR, and HMQC nuclear magnetic resonance experiments.


Assuntos
Colestanóis/química , Esteróis/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
15.
Acta Otolaryngol ; 103(5-6): 410-4, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3618168

RESUMO

The fast component of nystagmus begins where the slow component stops, at the point called the threshold of the fast component R. The fast component should last until the eye is brought back into the position of azimuth zero, where the slow component begins anew. This point can be called the threshold of the slow component L. So the fast component has a span from R to L and is presented as a side of a triangle r. An additional corrective procedure in electronystagmography is suggested to avoid failures and to define the true position of L. This is the way to correct the false information on nystagmic elements and to learn the unknown features of the fast component.


Assuntos
Nistagmo Patológico/fisiopatologia , Eletronistagmografia , Humanos
16.
Am J Chin Med ; 11(1-4): 102-5, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6660197

RESUMO

34 patients suffering from Meniere's disease were treated by acupuncture. Prior to acupuncture most of them had been treated with various other medical means without satisfactory results. After acupuncture treatment their condition greatly improved. The classic symptoms of Meniere's disease are vertigo, tinnitus and deafness, but for all the treated patients vertigo was the most uncomfortable and distressing symptom. In all our cases vertigo stopped after a few acupuncture courses; but in our opinion it is more important to follow and control hearing threshold, since if it remains stable the other symptoms of Meniere's disease also do not persist. All our patients were regularly followed by careful audiometric studies several years after acupuncture treatment. In most cases hearing level had not greatly varied, so the other symptoms of Meniere's disease were not present in any large degree.


Assuntos
Terapia por Acupuntura , Doença de Meniere/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Acta Otolaryngol ; 79(3-4): 319-24, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1136772

RESUMO

The program of the electronystagmographic examinations in the pathology of the central nervous system contains 11 groups of tasks. Sixty signs of central impairments are listed, from which 26 nystagmic irregularities had a small diagnostic value. No sign occuring alone could be taken as pathognomonic, only a group of signs can be used for the impairment localization. Besides for the peripheral vestibular and the peripheral vestibulocochlear impairments, the authors succeeded to make a group containing pathogomonic signs for mixed vestibular impairments as well as for multiple sclerosis affecting vestibular structures.


Assuntos
Doenças do Sistema Nervoso Central/diagnóstico , Eletronistagmografia , Eletroculografia , Nervo Coclear , Humanos , Doenças do Labirinto/diagnóstico , Neoplasias do Sistema Nervoso Periférico/diagnóstico , Nervo Vestibular
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