Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Database
Publication year range
1.
Anal Bioanal Chem ; 405(8): 2699-711, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23341003

ABSTRACT

In this work non-invasive reflection infrared spectroscopy was used to discriminate between different Cu-based green pigments (namely, malachite, verdigris, chrysocolla, emerald green and phthalo green). The pigments, chosen because of their historical widespread use in artworks, were investigated as pure powders and in situ on painted models by reflection FTIR spectroscopy. The distortion arising as a result of the specular and diffuse component of reflected radiation was evaluated as function of the optical and surface properties of the investigated mock-ups. Use of the Kramers-Kronig (KK) algorithm to correct for the distortion arising from the surface reflection gave k index maxima shifted by more than 20 cm(-1) relative to those obtained in conventional transmission mode. These findings stress the need to carefully manage use of the KK algorithm on reflection spectra to avoid erroneous assignment. On the other hand, combination and overtone bands (which are enhanced by the diffuse reflection) were proved to enable reliable and sensitive identification of most of the pigments studied. Knowledge acquired by study of pure compounds and painted models was subsequently applied to interpret the spectra acquired from paintings and manuscripts.

2.
Epilepsia ; 36(7): 687-91, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7555986

ABSTRACT

The efficacy and tolerability of vigabatrin (VGB) in children with refractory partial epilepsy were assessed in a single-blind, add-on, fixed-sequence, placebo-controlled trial. After 1-month observation, the patients entered a 7-month treatment period that involved administration of placebo for 1 month followed by VGB at the initial dosage of 40 mg/kg/day, to be increased to 60 and 80 mg/kg/day at 2-month intervals if seizures persisted. Of the 46 children enrolled in the study, 7 dropped out prematurely due to lack of efficacy of the drug (n = 6) or increased seizure frequency (n = 1). In 11 patients who either became seizure-free (n = 3) or improved markedly (n = 8), treatment was completed at a dose < 80 mg/kg/day. The average number of seizures per month in the 39 patients who completed the study decreased from 97 during placebo to 21, 12, and 9 after 2, 4, and 6 months of VGB treatments respectively (p < 0.0001 at each time). Response to VGB remained statistically significant when dropouts were included in the evaluation. The number of patients who had > 50% reduction in seizure frequency after 2, 4, and 6 months was 28, 33, and 35, respectively. Eight patients became seizure-free during the last 2 months of VGB treatment (3 at 40, 3 at 60, and 2 at 80 mg/kg/day, as compared with none during placebo treatment). Serum levels of associated antiepileptic drugs (AEDs) showed no significant changes, except for serum phenytoin (PHT) concentration, which significantly (p < 0.01) decreased after VGB treatment.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Anticonvulsants/therapeutic use , Epilepsies, Partial/drug therapy , gamma-Aminobutyric Acid/analogs & derivatives , Anticonvulsants/administration & dosage , Anticonvulsants/adverse effects , Child , Child, Preschool , Data Interpretation, Statistical , Epilepsies, Partial/blood , Female , Humans , Male , Phenytoin/blood , Placebos , Single-Blind Method , Time Factors , Vigabatrin , gamma-Aminobutyric Acid/administration & dosage , gamma-Aminobutyric Acid/adverse effects , gamma-Aminobutyric Acid/therapeutic use
3.
Neuropediatrics ; 24(6): 332-6, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8133979

ABSTRACT

Fourteen children (6 M, 8 F) suffering from refractory epilepsy received LTG as add-on therapy. LTG was administered twice daily at dosages increasing up to 2 mg/kg/day (for patients taking VPA) or to 10 mg/kg/day for patients taking AEDs that induce hepatic metabolism. The drug was withdrawn for side effects in 3 cases (rash: two cases, hirsutism: one), because of increased seizure frequency in 2 cases and because of unchanged seizure frequency in one. One patient died from acute respiratory failure, after repeated respiratory tract infections. A decrease in seizure frequency after one year of treatment with LTG was observed in 6 of the 7 patients who completed the study. The median total seizure frequency decreased from 10.7 +/- 7.3 to 3.8 +/- 4.6 seizures per day. At the end of the study, seizure frequency had decreased by more than 50% in 2 patients, by more than 75% in 2 patients, and 2 patients were seizure-free; in the remaining patient seizure frequency was unchanged. The best results were obtained with plasma LTG concentrations ranging from 0.5 to 5.4 micrograms/ml; no further improvement was observed at higher LTG concentrations.


Subject(s)
Anticonvulsants/pharmacology , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Triazines/therapeutic use , Adolescent , Child , Child, Preschool , Dose-Response Relationship, Drug , Drug Tolerance , Female , Humans , Lamotrigine , Male , Plasma/chemistry , Treatment Outcome , Triazines/administration & dosage , Triazines/blood
4.
G Ital Cardiol ; 19(4): 319-23, 1989 Apr.
Article in Italian | MEDLINE | ID: mdl-2753276

ABSTRACT

In order to study the prevalence of cardiac rhabdomyoma in tuberous sclerosis using non invasive methods, 11 consecutive patients affected by tuberous sclerosis (age: 3 months-22 years, mean 6 years) were examined between January 1984 and April 1987. In each patient clinical examination, 12 lead electrocardiogram, M-mode and two-dimensional echocardiogram were performed: on 7 of them a 24-hour ambulatory electrocardiogram was also performed. Clinical examination revealed a systolic murmur (grade 3/6) in two cases. In one of them it was associated with cyanosis and cardiac failure. None of other patients showed signs or symptoms related to the heart during clinical examination. ECG was abnormal in 3 cases (ventricular pre-excitation in 2 cases and left ventricular strain in 1). Two-dimensional echocardiogram showed single or multiple intracardiac masses suggestive of cardiac rhabdomyoma in 8 cases; in 3 of them masses were isolated, intramural, and in the interventricular septum, from 5 to 16 mm in diameter; in the other 5 cases they were multiple, intramural and endoluminal, in the interventricular septum, in the right or left ventricle, from 7 to 20 mm in diameter. Ambulatory electrocardiogram revealed only isolated ectopic supraventricular and ventricular beats in 2/7 cases. Each patient was clinically controlled every six months using ECG standard and two-dimensional echocardiogram. The mean follow-up period was 32 months (range 9-53). This study confirms the usefulness of the two-dimensional echocardiography to visualize intramural or intracavitary masses due to cardiac rhabdomyoma in patients with tuberous sclerosis, especially when they appear clinically asymptomatic. Two-dimensional echocardiography is probably the ideal method to use in order to evaluate potential increase in cardiac rhabdomyoma, when prolonged follow-up studies are performed.


Subject(s)
Echocardiography , Heart Neoplasms/diagnosis , Rhabdomyoma/diagnosis , Tuberous Sclerosis/complications , Adult , Child , Child, Preschool , Female , Humans , Infant , Male
SELECTION OF CITATIONS
SEARCH DETAIL
...