RESUMO
Hearing threshold has been measured in a group of patients following cochlear implantation with a Clarion device for the last eight years. The patients had received either a pre-curved carrier or the Hi-Focus I plus Electrode Positioner System (EPS). The assessment was carried out within the first post-operative week as well as at a later stage, between six and 87 months, post-operatively. Residual hearing thresholds were still measurable early after surgery in 24.5 per cent of the patients, without differences between the two different Clarion models. However, the number of subjects with measurable hearing dropped to 16.3 per cent as observed when hearing was measured at a later stage, with an equal distribution between the two groups of patients. From this study it has been possible to observe that only a limited number of patients maintain residual hearing after Clarion cochlear implantation, and that this tends to decrease further over time. Nevertheless, the performance of these patients for speech tests did not appear to be affected by deterioration of the pure-tone auditory threshold.
Assuntos
Implantes Cocleares , Perda Auditiva/prevenção & controle , Audiometria de Tons Puros , Limiar Auditivo , Estudos de Coortes , Perda Auditiva/fisiopatologia , Humanos , Período Pós-Operatório , Fatores de TempoRESUMO
A microporous material obtained from kanemite, a layered polysilicate, was studied in order to investigate its feasibility of including drugs and then releasing them. Diphenydramine hydrochloride was chosen as a model drug. The preparation of the microporous material and its loading with the drug are described. As kanemite is able to intercalate anions between its layers, the intercalation compound of diphenydramine and kanemite was also prepared. Both the drug-loaded microporous material and the intercalation compound were submitted to dissolution tests at pH 7.5. The drug release profiles from these two different materials and from a physical mixture were compared.
Assuntos
Excipientes , Silicatos/química , Difenidramina/química , Substâncias Intercalantes/química , Porosidade , Solubilidade , Solventes , Difração de Raios XRESUMO
From the wood of QUASSIA AMARA L. (Simarubaceae) two new canthin-6-one alkaloids have been isolated and their structures determined as 3-methyl-4-methoxy-5-hydroxycanthin-2,6-dione ( 1) and 4-methoxy-5-hydroxycanthin-6-one 3-, N-oxide ( 2) by spectroscopic and chemical methods. 3-Methylcanthin-5,6-dione ( 3) has been also isolated and identified for the first time from this source.
RESUMO
Three beta-carboline alkaloids have been isolated for the first time from the wood of QUASSIA AMARA L. (Simarubaceae) and their structures were determined to be 1-vinyl-4,8-dimethoxy-beta-carboline ( 1), 1-methoxycarbonyl-beta-carboline ( 2), and 3-methylcantin-2,6-dione ( 3) by spectral and chemical means.
RESUMO
Three species of the family of Compositae were extracted, partitioned and fractioned on silica gel column. The chromatographic fractions were investigated for cytostatic activity in vitro against human KB (human carcinoma of nasopharynx) cell line. The most interesting results were obtained with the first eight fractions of Senecio inaequidens DC, chloroformic extract, which showed marked cytostatic activity and appeared worthy of further investigations.
Assuntos
Antineoplásicos/isolamento & purificação , Carcinoma/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Extratos Vegetais/análise , Linhagem Celular , Células Cultivadas , Cromatografia em Gel/métodos , Humanos , Itália , Extratos Vegetais/fisiologiaRESUMO
Grosheimia macrocephala (Compositae) proved to be a very interesting natural source, not only of grosheimin (I), but also of cynaropicrin (III). Some derivatives from these two natural sesquiterpene gamma-lactones were prepared (Schemes 2 and 3) and two new natural guaianolides: 4'-deoxy-cynaropicrin (V) and 4'-nor-2'-metoxy-cynaropicrin (VI) were isolated and structurally identified. A series of these compounds were submitted to in vitro preliminary testing of cytostatic activity against KB cell lines and relationships between bioactivity and chemical features were investigated.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Plantas Medicinais/análise , Sesquiterpenos/síntese química , Acetilação , Divisão Celular/efeitos dos fármacos , Fenômenos Químicos , Química , Humanos , Células KB/efeitos dos fármacos , Oxirredução , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologiaRESUMO
The isolation and structural elucidation of two flavonoids I and II found in Dittrichia viscosa, L., syn. Inula viscosa L., is reported.
