Search

Most bone marrow (BM) malignancies develop in association with an angiogenic phenotype and increased numbers of endothelial cells. The molecular mechanisms involved in the modulation and recruitment of BM endothelium are largely unknown and may provide novel therapeutic targets for neoplastic diseases. We observed that angiogenic stimulation of BM endothelial cells activates mTOR and engages its downstream pathways 4E-BP1 and S6K1, which are inhibited by the mTOR-specific blockers rapamycin and CCI-779. Both mTOR blockers significantly inhibit growth factor- and leukemia-induced proliferation of BM endothelium by inducing G0/G1 cell-cycle arrest. This effect is associated with down-regulation of cyclin D1 and cdk2 phosphorylation, and up-regulation of the cdk inhibitors p27(kip1) and p21(cip1). Under conditions that reproduce the biomechanical fluidic environment of the BM, CCI-779 is equally effective in inhibiting BM endothelial-cell proliferation. Finally, simultaneous blockade of mTOR and NF-kappaB pathways synergize to significantly inhibit or abrogate the proliferative responses of BM endothelial cells to mitogenic stimuli. This study identifies mTOR as an important pathway for the proangiogenic stimulation of BM endothelium. Modulation of this pathway may serve as a valid therapeutic intervention in BM malignancies evolving in association with an angiogenic phenotype.

Concerns about the safety of irinotecan (CPT-11) plus bolus 5-fluorouracil (5-FU)/leucovorin (LV) (the so-called Saltz regimen) have been previously reported. This prospective, multicenter, non-randomized study evaluated the anti-tumoral effect and toxicity of the Saltz regimen as first-line chemotherapy of 130 patients with advanced colorectal cancer (CRC). The median numbers of treatment cycles and infusions received per patient were 3 and 12, respectively. Eight (6.1) and 37 patients (28.5%) showed complete and partial responses, respectively [overall response rate=34.6% (95% confidence interval=20.7-48.5%)]. After a median follow up period of 9 months, 70 patients had died. The median progression-free survival and overall survival were 6.78 (0.3-33.8) and 8.26 months (range 0.3-33.8), respectively. The combined CPT-11/5-FU/LV treatment was well tolerated and no toxic deaths were reported. The most common grade 3/4 hematological toxicity was neutropenia (28% of patients and 3% of infusions), but no febrile neutropenia was reported. Delayed diarrhea was the most reported grade 3/4 non-hematological toxicity (21% of patients and 2% of infusions). Other non-hematological toxicities showed very low incidences. During the study five patients died due to factors not associated with disease progression. We conclude that the Saltz regimen administered on an outpatient basis was safe and well tolerated in patients with advanced CRC. Close monitoring of external patients together with an early treatment of toxicity was found to be essential to prevent severe and potentially fatal gastrointestinal or thromboembolic events previously reported with this CPT-11 combined regimen.

Background: 5-fluorouracil (5-FU), irinotecan, and oxaliplatin are the most active drugs in advanced colorectal cancer (CRC), and survival is improved with patient exposure to all of them. The efficacy and safety of an alternating schedule of continuous-infusion 5-FU with leucovorin (LV) plus oxaliplatin (ie, FOLFOX regimen) or irinotecan (ie, FOLFIRI regimen) was assessed in the first-line setting., Patients and Methods: Seventy-nine patients with previously untreated, unresectable CRC were included. Treatment consisted of 5-FU/LV (de Gramont schedule) plus oxaliplatin (85 mg/m2) alternated biweekly with the same 5-FU/LV regimen plus irinotecan (180 mg/m2). Treatment was maintained until tumor progression or unacceptable toxicity was noted., Results: Median age was 62 years. Performance status was 0/1 in 91% of patients, 63% had 1 organ involved, and 80% had liver metastases. A median of 6 courses per patient (range, 1-9) and a total of 952 infusions were given. The most frequent grade 3/4 toxic events were neutropenia (32%), diarrhea (26%), and asthenia (7%). Grade 1/2 neurotoxicity was seen in 59% of cases, but no grade 3/4 neurotoxicity was observed. There were no toxic deaths. An objective response rate of 54% (4 complete responses plus 39 partial responses) was attained. Median time to progression and overall survival were 13 months and 18 months, respectively., Conclusion: This alternating schedule is active, with efficacy results similar to those seen with sequential protocols, the advantages of less toxicity, and 100% patient exposure to irinotecan and oxaliplatin.

The polymer-assisted reaction of 4-(hydroxymethyl)furan-2(5H)-one (4HM2F) with 21 carboxylic acids using polystyrene-carbodiimide (PS-carbodiimide) yielded an ester library. Four of the esters, (5-oxo-2,5-dihydrofuran-3-yl)methyl acetate (IS-1), (5-oxo-2,5-dihydrofuran-3-yl)methyl butyrate (IS-2), (5-oxo-2,5-dihydrofuran-3-yl)methyl 2-methylpropanoate (IS-3), and (5-oxo-2,5-dihydrofuran-3-yl)methyl chloroacetate (IS-4), were tested as internal standards for the quantification of patulin in apple juice by gas chromatography-mass spectrometry in the selected ion monitoring mode (GC-MS-SIM). The developed method combines an AOAC official extractive step and a GC-MS-SIM analysis. Using a chromatographic column containing trifluoropropylmethylpolysiloxane as the stationary phase and IS-1 as the internal standard, it was possible to perform an accurate and precise quantification of underivatizated patulin in apple juice at concentrations down to 6 microg/L. A detection limit of 1 microg/L was established.

Virtually all cells accommodate to their mechanical environment. In particular, cells subject to flow respond to rapid changes in fluid shear stress (SS), cyclic stretch (CS), and pressure. Recent studies have focused on the effect of pulsatility on cellular behavior. Since cells of many different tissue beds are constantly exposed to fluid flows over a narrow range of frequencies, we hypothesized that an intrinsic flow frequency that is optimal for determining cell phenotype exists. We report here that cells from various tissue beds (bovine aortic endothelial cells (BAEC), rat small intestine epithelial cells (RSIEC), and rat lung epithelial cells (RLEC)) proliferate maximally when cultured in a perfusion bioreactor under pulsatile conditions at a specific frequency, independent of the applied SS. Vascular endothelial and pulmonary epithelial cell proliferation peaked under 1 Hz pulsatile flow. In contrast, proliferation of gastrointestinal cells, which in their physiological context are subject to no flow or higher wavelength signal, was maximum at 0.125 Hz or under no flow. Moreover, exposure of BAEC to pulsatile flow of varying frequency influenced their nitric oxide synthase activity and prostacyclin production, which reached maximum values at 1 Hz. Notably, the "optimal" frequencies for the cell types examined correspond to the physiologic operating range of the organs from where they were initially derived. These findings suggest that frequency, independent of shear, is an essential determinant of cell response in pulsatile environments., ((c) 2004 Wiley-Liss, Inc.)

Objectives: The combination of irinotecan and raltitrexed is safe and active in 5-fluorouracil-refractory, metastatic colorectal cancer (CRC), with the advantage of its convenient three-weekly schedule. The aim of this multicenter phase II study was to assess its efficacy and toxicity in first-line treatment., Methods: Between May 2000 and March 2001, 62 previously untreated patients received irinotecan (350 mg/m(2)) plus raltitrexed (3 mg/m(2)), with courses repeated every 21 days. Objective response was assessed every three courses, and treatment maintained until tumor progression or unacceptable toxicity., Results: A total of 331 cycles were administered, with a median of five cycles per patient (range, 1-16). Seventeen patients achieved a partial response and 2 a complete response, for an overall intention-to-treat response rate of 30% (95% confidence interval, 18-44%). The incidence of grade 3-4 toxicity per patient was diarrhea (27%), emesis (13%), anemia (12%), neutropenia (9%), and asthenia (7%). Three patients (5%) died from treatment-related adverse events (diarrhea plus neutropenia). The median potential follow-up is now 37 months. Median survival was 12.2 months, and median time to progression was 6.3 months., Conclusions: The combination of irinotecan plus raltitrexed is an easy comfortable schedule for patients with metastatic CRC, but both efficacy and toxicity results seem suboptimal for first-line treatment.

Background and Objective: Our objective was to study the outcome and compliance of both medical and alcoholism treatment in alcoholics discharged from a general hospital., Patients and Method: This was a 2 years prospective follow up study of a cohort of 100 inpatients referred to the Alcohol Unit during the first semester of 1998., Results: After 2 years, 9 patients had died and 14 had been referred to other hospitals. 15% of patients refused medical treatment from the beginning and alcoholism treatment was initially refused by 31% of alcoholics. At 2 years of follow up, compliance rates were 46% for medical treatment and 10% for alcoholism treatment. All patients under treatment for alcoholism were also good compliers of medical treatment. Survival analysis for alcoholism treatment at 2 years was 19%, with higher rates in patients with psychosocial problems and previous alcohol consultations. The probability of being alive was 89%., Conclusions: Few alcoholics are detected. Most of them display high levels of severity and poor prognosis, with high mortality rates. Compliance with follow up treatment is low. There is a clear correlation between compliance of alcoholism and medical treatment.

Background: We conducted a phase I/II study of weekly irinotecan [30 min intravenous (i.v.) infusion] combined with 5-fluorouracil (5-FU 3 g/m(2) weekly 48 h i.v. infusion, TTD regimen) as first-line chemotherapy for patients with advanced colorectal cancer (CRC)., Patients and Methods: The maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) in the treatment of gastrointestinal solid tumors (in phase I), and the antitumor activity and toxicity of the recommended phase I dose (in phase II) were determined., Results: Diarrhea was the DLT, and irinotecan 80 mg/m(2) plus 5-FU 3 g/m(2) was the recommended phase I dose. In phase II, the confirmed response rate was 44% [95% confidence interval (CI) 29% to 59%] and the median overall survival was 23.8 months. However, grade 3/4 diarrhea affected 59% of patients and led to withdrawal of three patients. A second cohort of patients studied using the same schedule but with a reduced 5-FU starting dose of 2.25 g/m(2) showed improved tolerance (the incidence of grade 4 diarrhea decreased from 28% to 11% and overall grade 3/4 diarrhea to 56%, with no patient withdrawals) but the confirmed response rate was 28% (95% CI 14% to 45%) and median overall survival was 17.2 months., Conclusions: We found weekly irinotecan 80 mg/m(2) plus TTD regimen (5-FU 2.25 g/m(2) given as 48-h i.v. infusion) to be a feasible and active combined chemotherapy for the first-line treatment of advanced colorectal cancer.

The clinical features, risk factors, neuroimaging findings, and outcome of acute ischemic stroke were assessed in patients with intermittent claudication. Data from 142 patients with ischemic stroke and intermittent claudication were collected from a prospective hospital-based stroke registry in which 2500 consecutive acute stroke patients attended over a 12-year period. Ischemic stroke in patients with intermittent claudication accounted for 7.7% of all ischemic strokes (n = 1840). Ischemic stroke with and without intermittent claudication showed a similar in-hospital mortality rate (16% vs 14%) and absence of functional limitation at hospital discharge (20.5% vs 18.5%). Ischemic stroke patients with intermittent claudication showed a significantly shorter length of stay than patients without symptomatic peripheral arterial disease (14.6 vs 18.8 days, p < 0.05). Ischemic heart disease, transient ischemic attack (TIA), renal dysfunction, and watershed infarct were significant independent predictors of ischemic stroke in patients with intermittent claudication. Although cerebral infarction in patients with intermittent claudication showed a clinical profile suggestive of poor outcome, the prognosis was similar to that of ischemic stroke without intermittent claudication.

Background: We hypothesized that previous transient ischemic attack (TIA) had a favorable effect on early outcome after acute nonlacunar ischemic stroke., Methods: Data of 1,753 consecutive patients with ischemic stroke collected from a prospective hospital-based stroke registry were studied. A comparison was made of the groups with and without previous TIA. Favorable outcome included spontaneous neurological recovery or grades 0-2 of the modified Rankin scale at hospital discharge., Results: Previous TIA occurred in 55 (11.5%) of 484 patients with lacunar stroke and in 166 (13.1%) of 1,269 patients with nonlacunar stroke. The percentage of nonlacunar ischemic stroke patients with favorable outcome was 21.7% in those with a history of TIA compared to 15% without TIA (p < 0.03). In the lacunar stroke group, differences were not significant. In the multivariate analysis, TIA was an independent predictor of spontaneous in-hospital recovery., Conclusions: Prior TIA was associated with a favorable outcome in nonlacunar ischemic stroke, suggesting a neuroprotective effect of TIA possibly by inducing a phenomenon of ischemic tolerance allowing better recovery from a subsequent ischemic stroke.

Aims: We performed a double-blind, placebo-controlled randomized trial of sertraline in recently detoxified alcohol-dependent patients with current depressive symptoms. The objectives of the study were to evaluate the efficacy of sertraline at achieving stable abstinence, at ameliorating depressive symptoms and at improving quality of life in these patients., Methods: The study included 83 patients, who received either sertraline (50-150 mg/day) or placebo for 24 weeks. The primary outcome criteria were the rate of relapse into alcohol consumption and the rate of response on the Montgomery and Asberg Depression Rating Scale (MADRS)., Results: At the end of the treatment period, relapse rates were 23.1% in the placebo group and 31.8% in the sertraline group. Responder rates for depression were 38.5% for the placebo group and 44.2% for the sertraline group. There was no significant difference between treatment groups with either variable. However, when patients were stratified into severe (MADRS score >or=26) and moderate (MADRS score <26) depression at inclusion, a significant treatment benefit with sertraline was observed in the former group. Quality of life, determined by the SF-36, improved in both groups, with more benefit observed for the sertraline group on mental health items. Sertraline was well tolerated, and the incidence of adverse events was similar in the two treatment groups., Conclusions: The explanation for the overall good outcome in both treatment groups and for the inability to demonstrate a clear treatment effect may reside in the clinical features of the patients included.

We assessed predictors of spontaneous early neurological recovery after acute ischemic stroke by means of multivariate analysis in a cohort of 1,473 consecutive patients treated at one academic center. At hospital discharge, spontaneous neurological improvement or good outcome was defined as grades 0-2 of the Rankin scale, and poor outcome (no improvement or in-hospital death) as grades 3-5. Spontaneous recovery of neurological deficit at the time of discharge from the hospital was observed in 16% of patients with cerebral infarction (n = 238). Dysarthria-clumsy hand syndrome improved in 44% of patients and was the only variable significantly associated with in-hospital functional recovery in three logistic regression models that in addition to lacunar syndromes, included demographic variables, cardiovascular risk factors, and clinical variables [odds ratio (OR) 2.56], neuroimaging findings (OR 2.48), and outcome data (OR 2.39), respectively. Clinical factors related to severity of infarction available at stroke onset have a predominant influence upon in-hospital outcome and may help clinicians to assess prognosis more accurately. Our work gives a contribution into prognostic factors after acute ischemic stroke. With regard to patterns of stroke, dysarthria-clumsy hand syndrome was a significant predictor of spontaneous in-hospital recovery in ischemic stroke patients.

We report fabrication, characterization, and use of microfluidic analysis devices containing surface-immobilized cell-capturing molecules. Amino-terminated biotin ligands are immobilized onto the luminal surface of a microdevice and effectively support self-assembly of proteins, antibodies, and mammalian cells. For this purpose, chemical vapor deposition (CVD) polymerization is used to functionalize PDMS-made microfluidic devices with poly[para-xylylene carboxylic acid pentafluorophenolester-co-para-xylylene]. The resulting reactive coating shows excellent adhesion when deposited in thin films (approximately 100 nm, and the distribution of the pentafluorophenol ester groups is reasonably uniform within the microchannel inner surface, as examined by fluorescence microscopy. The utility of these devices for cell-based bioassays is demonstrated by monitoring the concentration-dependent effect of the disintegrin echistatin on cell adhesion. The described assay format could be relevant to clinical research in various fields, including angiogenesis research.

We studied the influence of very early seizures (within 48 h of stroke onset) on in-hospital mortality in a cohort of 452 consecutive patients with atherothrombotic infarction. These patients were selected from 2000 consecutive acute stroke patients registered in a prospective hospital-based stroke registry in Barcelona, Spain. A comparison of data between the nonseizure (n = 442) and seizure (n = 10) groups was made. Predictors of very early seizures were assessed by multivariate analysis. The in-hospital mortality rate was significantly higher in atherothrombotic stroke patients with very early seizures than in those without seizures (70 vs. 19.5%, p < 0.001). Independent predictors of in-hospital mortality included very early seizures, congestive heart failure, atrial fibrillation, 85 years of age or older, altered consciousness, dizziness, parietal and pons involvement, and respiratory and cardiac complications. After multivariate analysis, atherothrombotic infarction of occipital topography and decreased consciousness appeared to be independent predictors of atherothrombotic stroke with very early seizures. Very early seizures constitute an important risk factor for in-hospital mortality after atherothrombotic stroke., (Copyright 2003 S. Karger AG, Basel)

A new methodology for obtaining chlorohydrin esters using a one-pot esterification-chlorination reaction, in which one of the reagents, chlorotrimethylsilane, acts as solvent, is described. The reaction is stereospecific and its regioselectivity depends on the number of carbons between the hydroxyl groups present in the starting material. A mechanism is proposed.

As certain proteins control cell adhesion, it has been hoped that cell transplantation and tissue engineering could be augmented by pre-adsorption of specific proteins to biological or synthetic surfaces. The questions that remain, however, are whether such proteins can affect cell production as well as adhesion, and if so, whether in a protein-specific manner. We examined the adhesion and the biochemical secretion of bovine aortic endothelial cells (BAEC) on tissue culture polystyrene (TCPS) discs coated with fibronectin (Fn), laminin (Ln), or gelatin. The three coating proteins nonspecifically promote sub-confluent and post-confluent endothelial cell production of total protein up to 2.5-fold of the reference value. Total soluble glycosaminoglycan (GAG) production slightly increased with the different coatings only at low cell density. In contrast, Ln and Fn, not gelatin, drastically enhanced post-confluent BAEC production of prostaglandin (PGI2). However, antibody-blockage of the alpha5 integrin, constituent of the Fn receptor in BAEC, appeared to inhibit the upregulation of PGI2 production observed on Fn-coated surfaces. The results indicate that the cell adhesion mediators used as coating agents dictate cell biological production as well as adhesion and proliferation.

Background: To characterize the vascular risk factor profiles in ischemic stroke and in intracerebral hemorrhage., Patients and Method: The study population consisted of 1,473 consecutive ischemic stroke patients and 229 consecutive intracerebral hemorrhagic patients collected in the Sagrat Cor Hospital of Barcelona Stroke Registry over a 10-year period. The prevalence of vascular risk factors in ischemic stroke and in intracerebral hemorrhage was analyzed by means of univariate analysis and a logistic regression model., Results: Hypertension was present in 52% of ischemic stroke patients and in 60.7% of intracerebral hemorrhagic patients. The pattern of risk factors associated with ischemic stroke included valve heart disease (OR = 5.96; 95% CI, 1.42-24.88), transient ischemic attack (OR = 4.16; 95% CI, 2-8.64), atrial fibrillation (OR = 2.95; 95% CI, 1.88-4.64), previous brain infarct (OR = 2.58; 95% CI, 1.53-4.35), ischemic heart disease (OR = 2.55; 95% CI, 1.41-4.62), hyperlipidemia (OR = 2.12; 95% CI, 1.32-3.4), hypertension (OR = 0.64; 95% CI, 0.48-0.87), chronic liver disease (OR = 0.32; 95% CI, 0.14-0.73), previous cerebral hemorrhage (OR = 0.24; 95% CI, 0.09-0.64) and oral anticoagulant therapy (OR = 0.11; 95% CI, 0.03-0.36)., Conclusions: Different potentially modifiable vascular risk factors profiles were identified in ischemic versus hemorrhagic stroke.

The combination of ifosfamide and irinotecan was tested in a dose-finding study. The preliminary results of the combination in this phase I study did not show any major toxicity that could help to define the dose-limiting toxicity. The escalation continues even after nine levels; the study is therefore ongoing. The main toxicity is gastrointestinal, with mild nausea, vomiting, and diarrhea. There was some other irrelevant toxicity, which was easily manageable with the usual supportive therapy. When responses were evaluated, stable disease was found in some cases, suggesting some activity for the combination.

Several N-(4-phenoxyphenyl)pyridinecarboxamides and N-(4-phenoxyphenyl)pyrazinecarboxamides were synthesized from commercially available material, and their ovicidal activities against Cydia pomonella (L.) were tested. Some of the tested products showed a moderate activity when <24-h-old eggs were sprayed using a Potter tower. A significant increase in the length of the development period of the eggs was also observed in many cases. A clear correlation between both effects was noticed: the products that produced higher mortality also produced higher increase of the length of the development. These results seem to confirm our hypothesis that these compounds could be defined as a juvenile hormone analogues.

Protein adsorption at polymer surfaces has been investigated by means of both ELISA and radiolabeling techniques. Most of the data obtained are linearly related to each other for protein concentrations between 0.01 and 1 µg/ml, i.e., the concentration range in which the maximum amount of adsorbed active protein (ELISA) is achieved. The correlation of ELISA data with radioisotope-based measurements allows quantification of the former. Specific correlation factors are described. Adsorption is shown to be strongly dependent on the polymer/protein system. Copyright 1999 Academic Press.