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At least 145 records · Page 8Linked to original sources
PubMed1997

Limiting lexical activation limits perceptual priming in masked word identification.

Four experiments tested the hypothesis that perceptual priming of a word depends on the prior lexical processing of the word (Rajaram & Roediger, 1993; Weldon, 1991). Experiment 1 showed that first-letter naming reduced priming relative to reading a whole word on two tests: word fragment completion and masked word identification. In Experiment 2, naming the first letter of a word took longer than naming the letter presented alone, and led to better masked word identification. Experiment 3 showed that masked word identification was enhanced by prior word processing more for low frequency words than for high frequency words, but only when words had been read aloud. Experiment 4 tested whether the auditory input accruing from reading a word aloud was the source of facilitation and frequency effects. Participants judged either the frequency of the whole display or the positional frequency of the first letter in the display, and indicated their decisions manually. The major findings from Experiment 3 were replicated, ruling out the cross-modal source of those effects. It was concluded that activation of a lexical unit, one component of word processing (Vriezen, Moscovitch, & Bellos, 1995), is a critical determinant of the perceptual priming of that word.

Adult↗
PubMed1988

Disposition of a flow-limited drug (lidocaine) and a metabolic capacity-limited drug (theophylline) in liver cirrhosis.

The plasma clearance after oral administration of a completely absorbed drug that is metabolized by the liver depends on its intrinsic clearance. In cirrhosis the bioavailability of a flow-dependent drug increases because of both portosystemic shunting and hepatocyte dysfunction. A drug with a high extraction ratio, lidocaine, and a drug with a low extraction ratio, theophylline, were administered to 27 patients with cirrhosis and 16 control subjects. We found a significant impairment of both theophylline clearance (p less than 0.001) and lidocaine clearance (p less than 0.001) and an increase in the lidocaine peak concentration (p less than 0.001). The three parameters were significantly correlated with each other. The impairment of theophylline metabolism did not correlate with other indexes of disease severity, whereas lidocaine clearance was lower and lidocaine peak level higher in patients with decompensated cirrhosis and evidence of portal hypertension. Thus impairment in lidocaine disposition, which reflects both hepatocyte dysfunction and portosystemic shunting, correlated closer with the severity of liver disease than did theophylline metabolism.

Adult↗
PubMed2001

Phase II study of a high-dose ifosfamide-based chemotherapy regimen with growth factor rescue in recurrent aggressive NHL. High response rates and limited toxicity, but limited impact on long-term survival.

The purpose of the study was to evaluate in patients with recurrent intermediate-grade NHL, the tolerance to and efficacy of an intensive salvage regimen consisting of high doses of ifosfamide, etoposide and mitoxantrone with G-CSF support, followed by autologous stem cell transplantation and to identify prognostic factors for survival in patients with recurrent aggressive lymphoma. Patients with recurrent intermediate-grade NHL under the age of 60 years were eligible. Induction consisted of ifosfamide 10 g/m(2) and etoposide 900 mg/m(2) with G-CSF 5 microg/kg twice a day. Upon recovery, patients underwent stem cell apheresis. Patients achieving complete remission (CR) underwent autologous stem cell transplantation using BEAM conditioning. Those with partial remission (PR) received treatment with ifosfamide 10 g/m(2), mitoxantrone 20 mg/m(2) and G-CSF 5 microg/kg. Those with CR received BEAM, those with PR received cyclophosphamide 4.5 g/m(2), etoposide 1200 mg/m(2) and cisplatin 135 mg/m(2) with stem cell rescue followed by BEAM. Antibiotic prophylaxis was given with all treatment cycles. The results were compared with those obtained in a prior study that used MINE-ESHAP salvage. Forty-four patients with recurrent intermediate-grade NHL were enrolled between March 1994 and September 1996. Median age was 50 years (24-61). Eleven patients had transformed lymphoma and seven had a T cell phenotype. Response rate to the high-dose ifosfamide regimen was 77% +/- 12% after two cycles and the complete response rate was 41% +/- 14%. Myelosuppression was profound but short. Median nadir ANC was 0 and the median duration of ANC <0.5 x 10(9)/l was 6 days (range 3-12). No severe infections occurred; 55% of the patients required blood transfusion and 42% required platelet transfusions. Myelosuppression and transfusion requirements were similar after the first and second cycles. Thirty-five of the 44 patients proceeded to autologous stem cell transplantation and one transplant-related death occurred. With a median follow-up of 52 months, progression-free survival at 2 years is 38% +/- 14% and survival is 52% +/- 15%. Data from these 44 patients were pooled with data on 53 patients who had received salvage treatment with MINE-ESHAP, for a multivariate analysis of prognostic factors. In multivariate analysis, serum LDH was strongly associated with survival. The use of a more intensive salvage regimen, did not result in a significant increase in long-term outcome, despite a high response rate. In conclusion, duration of treatment, response rates, treatment-related mortality and survival compare favorably with previous salvage regimens, but recurrence remains a major problem. Long-term survival in recurrent large cell lymphoma is influenced more by disease characteristics than by the type of salvage regimen used.

Adolescent↗
PubMed2004

Soyasaponin I and sapongenol B have limited absorption by Caco-2 intestinal cells and limited bioavailability in women.

A human study was conducted to evaluate soyasaponin bioavailability in humans. Eight healthy women ingested a single dose of concentrated soy extract containing 434 micromol of group B soyasaponins, the predominant form of soyasaponins in soybeans. Neither soyasaponins nor their metabolites were detected in a 24-h urine collection. Soyasapogenol B, a major metabolite of group B soyasaponins, was found (36.3 +/- 10.2 micromol) in a 5-d fecal collection but no group B soyasaponins were detected. A human colon cancer Caco-2 cell model was used to evaluate the absorbability of soyasaponins at the mucosal level. The mucosal transfers of soyasaponin I and soyasapogenol B were 0.5-2.9 and 0.2-0.8%, respectively, after 4-h incubation on the Caco-2 monolayer. The apical to basolateral absorptions of soyasaponin I and soyasapogenol B were low with P(app) of 0.9 to 3.6 x 10(-6) and 0.3 to 0.6 x 10(-6) cm/s, respectively. The transport rate and cell uptake of soyasaponin I were saturable and concentration-independent. In contrast, soyasapogenol B was taken up by Caco-2 cells in a concentration-dependent manner. Soyasaponin I had no apparent cytotoxic effect on Caco-2 cells at concentrations up to 3 mmol/L, whereas soyasapogenol B at 1 mmol/L or more significantly reduced cell viability. Therefore, ingested soyasaponins have low absorbability in human intestinal cells and seem to be metabolized to soyasapogenol B by human intestinal microorganisms in vivo and excreted in the feces.

Administration, Oral↗