Barriers to patient recruitment in a poststroke neurorehabilitation multicenter trial in Brazil.

There is a high demand for stroke rehabilitation in the Brazilian public health system, but most studies that have addressed rehabilitation for unilateral spatial neglect (USN) after stroke have been performed in high-income countries. Therefore, the aim of this study was to analyze USN patient recruitment in a multicenter noninvasive brain stimulation clinical trial performed in Brazil and to provide study design recommendations for future studies. We evaluated the reasons for exclusion of patients from a multicenter, randomized, double-blinded clinical trial of rehabilitation of USN patients after stroke. Clinical and demographic variables were compared between the included and excluded patients. A descriptive statistical analysis was performed. Only 173 of the 1953 potential neglect patients (8.8%) passed the initial screening. After screening evaluation, 87/173 patients (50.3%) were excluded for clinical reasons. Cognitive impairment led to the exclusion of 21/87 patients (24.1%). Low socioeconomic status led to the exclusion of 37/173 patients (21.4%). Difficulty obtaining transportation to access treatment was the most common reason for their exclusion (16/37 patients, 43.3%). The analyzed Brazilian institutions have potential for conducting studies of USN. The recruitment of stroke survivors with USN was restricted by the study design and limited financial support. A history of cognitive impairment, intracranial stenting or craniectomy, and lack of transportation were the most common barriers to participating in a multicenter noninvasive brain stimulation trial among patients with USN after stroke.

Barriers to patient recruitment in a poststroke neurorehabilitation multicenter trial in Brazil

There is a high demand for stroke rehabilitation in the Brazilian public health system, but most studies that have addressed rehabilitation for unilateral spatial neglect (USN) after stroke have been performed in high-income countries. Therefore, the aim of this study was to analyze USN patient recruitment in a multicenter noninvasive brain stimulation clinical trial performed in Brazil and to provide study design recommendations for future studies. We evaluated the reasons for exclusion of patients from a multicenter, randomized, double-blinded clinical trial of rehabilitation of USN patients after stroke. Clinical and demographic variables were compared between the included and excluded patients. A descriptive statistical analysis was performed. Only 173 of the 1953 potential neglect patients (8.8%) passed the initial screening. After screening evaluation, 87/173 patients (50.3%) were excluded for clinical reasons. Cognitive impairment led to the exclusion of 21/87 patients (24.1%). Low socioeconomic status led to the exclusion of 37/173 patients (21.4%). Difficulty obtaining transportation to access treatment was the most common reason for their exclusion (16/37 patients, 43.3%). The analyzed Brazilian institutions have potential for conducting studies of USN. The recruitment of stroke survivors with USN was restricted by the study design and limited financial support. A history of cognitive impairment, intracranial stenting or craniectomy, and lack of transportation were the most common barriers to participating in a multicenter noninvasive brain stimulation trial among patients with USN after stroke.

A phase I-II study of weekly oxaliplatin, 5-fluorouracil continuous infusion and preoperative radiotherapy in locally advanced rectal cancer.

BACKGROUND: Oxaliplatin (OXA) significantly enhanced the antitumour activity of 5-fluorouracil (FUra) in patients with advanced colorectal cancer and displayed radiosensitising properties in preclinical studies. This study was thus performed to test the feasibility, identify the recommended doses (RDs) and explore preliminarily the clinical activity of weekly OXA and infused FUra combined with preoperative pelvic radiotherapy. PATIENTS AND METHODS: Forty-six patients with recurrent or locally advanced (cT3-4 and/or N+) adenocarcinomas of the mid-low rectum were treated with escalating doses of OXA (25, 35, 45, 60 mg/m2, weekly for 6 weeks) and FUra (200-225 mg/m2/day, 6-week infusion) concurrent to preoperative pelvic radiotherapy (50.4 Gy/28 fractions). The RDs for the phase II part of the study were immediately below the level resulting in dose-limiting toxicities in more than one third of the patients, or corresponded to the last planned dose level. RESULTS: In the escalation phase, dose-limiting toxicities only occurred in one patient at the fourth level and one of six patients treated at the last planned dose level (grade III diarrhoea). OXA 60 mg/m2 and FUra 225 mg/m2/day are therefore the RDs for the regimen. Among 25 patients globally treated at these doses (phase II part), the incidence of grade III diarrhoea was 16% with no grade IV toxicity. Neurotoxicity did not exceed grade II (12%). All patients completed radiotherapy and were operated on as scheduled. Twenty-one of 25 patients had the tumour down-staged after chemoradiation with seven (28%) pathological complete responses and 12 (48%) residual tumours limited to ypT1-2N0. CONCLUSIONS: Weekly OXA, at doses potentially active systemically, can be combined with full-dose, infused FUra and radiotherapy. Given the low toxicity and promising activity, this regimen is being compared to standard FUra-based pelvic chemoradiation in a randomised study.

Preliminary evaluation of inhibition of matrix-metalloprotease MMP-2 and MMP-9 by Passiflora edulis and P foetida aqueous extracts.

Fruit's decoctions of Passiflora edulis and P. foetida var. albiflora were evaluated for the inhibition of activity of gelatinase MMP-2 and MMP-9, two metallo-proteases involved in the tumour invasion, metastasis and angiogenesis. Both water extracts, at different concentrations, inhibited the enzymes.

Inhibition of endothelial cell functions and of angiogenesis by the metastasis inhibitor NAMI-A.

NAMI-A is a ruthenium-based compound with selective anti-metastasis activity in experimental models of solid tumours. We studied whether this activity was dependent on anti-angiogenic ability of NAMI-A. We thus investigated its in vitro effects on endothelial cell functions necessary for angiogenesis to develop, as well as its in vivo effects in the chick embryo chorioallantoic membrane model. Endothelial cell proliferation, chemotaxis, and secretion of the matrix-degrading enzyme metalloproteinase-2 were inhibited by NAMI-A in a dose-dependent manner, and without morphologic signs of cell apoptosis or necrosis. Lastly, NAMI-A displayed a dose-dependent in vivo anti-angiogenic activity in the chorioallantoic membrane model. These data suggest that the anti-angiogenic activity of NAMI-A can contribute to its anti-metastatic efficacy in mice bearing malignant solid tumours.

Tumor gelatinases and invasion inhibited by the green tea flavanol epigallocatechin-3-gallate.

BACKGROUND: Given the association of consumption of green tea with prevention of cancer development, metastasis, and angiogenesis, the effect of the main flavanol present, epigallocatechin-3-gallate (EGCG), on two gelatinases most frequently overexpressed in cancer and angiogenesis (MMP-2 and MMP-9) and on tumor cell invasion and chemotaxis were examined. METHODS: Zymography, Western blotting, and enzyme linked immuoadsorbent assay were used to analyze the effect of EGCG on MMP-2 and MMP-9 activity, whereas its effect on tumor cell invasion and chemotaxis was examined using modified Boyden chamber assays. RESULTS: A Zn2+ chelation-independent, dose-dependent, noncompetitive inhibition by EGCG of both gelatinases was found at concentrations 500 times lower than that reported to inhibit urokinase. Tumor cell invasion of a reconstituted basement membrane matrix, but not chemotaxis, was reduced by 50% with EGCG concentrations equivalent to that in the plasma of moderate green tea drinkers, and 2 orders of magnitude below those of tissue inhibitors of MMPs. Although higher concentrations of EGCG were associated with increased levels of both cell-associated gelatinases and their activator MT1-MMP, no increased gelatinase activation was found, and TIMP-1 and TIMP-2 inhibitors were up-regulated. Finally, concentrations of EGCG active in restraining proliferation and inducing apoptosis of transformed cells were more than 100 times lower than those reported for normal cells. CONCLUSIONS: Epigallocatechin-3-gallate is a potent inhibitor of gelatinases and an orally available pharmacologic agent that may confer the antiangiogenic and antimetastatic activity associated with green tea.

Augmented membrane type 1 matrix metalloproteinase (MT1-MMP):MMP-2 messenger RNA ratio in gastric carcinomas with poor prognosis.

The activation of zymogen and the amount of proteinase and its inhibition are important in determining the eventual activity of matrix-degrading enzymes involved in tumor aggressiveness. To evaluate a gene complement leading to matrix metalloproteinase 2 (MMP-2; Mr 72,000 gelatinase) activity, membrane type 1 MMP (MT1-MMP), urokinase-type plasminogen activator, MMP-2, and tissue inhibitor of metalloproteinase 2 transcriptional levels were measured in gastric carcinoma biopsies. Comparative tumor:normal tissue reverse transcription-PCR in a cohort of 25 patients revealed up to a 10-fold difference in the expression of MT1-MMP, a metalloproteinase that has been proposed as a membrane receptor activator of MMP-2; a 1-unit increment resulted in a 30% risk to survival. A 20% risk also resulted from a 1-unit increment in the MT1-MMP: MMP-2 ratio, which showed differences of up to 15-fold. Instead, the expression of urokinase-type plasminogen activator, which trips off a cascade ending in the activation of MMP-2, as well as the expression of MMP-2 itself and its inhibitor, tissue inhibitor of metalloproteinase 2, lacked correlation with patient follow-up. Zymography revealed MMP-2 activities that were often in conflict with the transcription results and also with follow-up. The results suggest the evaluation of MT1-MMP and/or MT1-MMP:MMP-2 transcription as a new preoperative molecular-level prognostic factor for gastric carcinoma.