Sulfide as a confounding factor in toxicity tests with the sea urchin Paracentrotus lividus: comparisons with chemical analysis data

Sperm cell and embryo toxicity tests with the sea urchin Paracentrotus lividus were performed to assess the toxicity of sulfide, which is considered a confounding factor in toxicity tests. For improved information on the sensitivity of these methods to sulfide, experiments were performed in the same aerobic conditions used for testing environmental samples, with sulfide concentrations being monitored at the same time by cathodic stripping voltammetry. New toxicity data for sulfide expressed as median effective concentration (EC50) and no-observed-effect concentration (NOEC) are reported. The EC50 value for the embryo toxicity test (total sulfide at 0.43 mg/L) was three times lower than for the sperm cell test (total sulfide at 1.20 mg/L), and the NOEC values were similar (on the order of total sulfide at 10(-1) mg/L) for both tests. The decrease in sulfide concentration during the bioassay as a consequence of possible oxidation of sulfide by dissolved oxygen was determined by voltammetric analysis, indicating a half-life of about 50 min in the presence of gametes. To check the influence of sulfide concentrations on toxicity effects in real samples, toxicity (with the sperm cell toxicity test) and chemical analyses also were performed in pore-water samples collected with an in situ sampler in sediments of the Lagoon of Venice (Italy). A highly positive correlation between increased acute toxicity and increased sulfide concentration was found. Examination of data revealed that sulfide is a real confounding factor in toxicity testing in anoxic environmental samples containing concentrations above the sensitivity limit of the method.     

Weekly gemcitabine, paclitaxel, oxaliplatin combination chemotherapy in patients with Cisplatin-refractory germ cell tumor: preliminary experience

Although the overall cure rate for advanced germ cell tumor (GCT) is high, the prognosis for patients with cisplatin-refractory GCT remains poor. Gemcitabine, paclitaxel, and oxaliplatin have shown significant activity as single agents in these patients. We investigated the activity and tolerance of a weekly gemcitabine, paclitaxel, oxaliplatin chemotherapy regimen. From September 2000 to February 2002, 9 patients with cisplatin-refractory GCT were treated with gemcitabine 800 mg/m2, paclitaxel 70 mg/m2, and oxaliplatin 50 mg/m2, days 1, 8, and 15, every 4 weeks. Only 1 patient stayed on schedule. In 7 patients, chemotherapy treatment was modified due to grade 3-4 hematological toxicity, whereas in another patient, who received high-dose chemotherapy 2 months before, chemotherapy was administered biweekly. In total, 21 cycles were administered with a median of 2 cycles for each patient. One patient achieved a partial remission lasting 5 months, 1 had disease stabilization for 5 months, whereas 7 had progressive disease. This chemotherapy regimen was not feasible in our patient population. Recently, oxaliplatin at full doses, but not as weekly administration, has appeared to possess activity in cisplatin-refractory GCT. Thus, we plan a phase II study protocol of the oxaliplatin and gemcitabine combination at full doses every 3 weeks.     

Retrospective study of resection of pulmonary metastases in patients with advanced colorectal cancer: the development of a preoperative chemotherapy strategy

Considerable data are available to support the resection of hepatic metastases in patients with colorectal cancer, but there are relatively few studies on the role of pulmonary metastectomy. The small number of such studies is mainly noncontemporaneous and predates the use of preoperative neoadjuvant chemotherapy. A retrospective analysis of 31 patients with pulmonary metastases from colorectal cancer treated with surgery and perioperative chemotherapy between 1995 and 2003 was performed. Twenty patients (65%) proceeded directly to surgery and 5 of these received postoperative chemotherapy. Eleven patients (35%) received preoperative chemotherapy, which consisted of a fluoropyrimidine in combination with oxaliplatin or mitomycin-C, except for 1 patient who received single agent irinotecan. Nine of 11 patients (82%) had a partial response and 2 patients (18%) had stable disease. A total of 39 thoracic surgeries (6 bilateral and 1 incomplete) were performed. There were no postoperative deaths. Four of 20 patients (20%) who had initial surgery had postoperative complications, compared with 18% of the preoperative chemotherapy group. Overall 3- and 5-year survival rates after the first thoracic surgery were 65.2% (95% CI, 35.1%-83.9%) and 26.1% (95% CI, 4.3%-56.2%), respectively. Based on the limited data from this study, disease-free interval, number of pulmonary metastases, previous resection of hepatic metastases, prethoracotomy carcinoembryonic antigen levels, and preoperative chemotherapy were not found to be significant prognostic factors for survival. Therefore, surgical resection of lung metastases is associated with low morbidity and mortality and results in long-term survival for 20%-30% of patients. Moreover, preoperative chemotherapy produced a high response rate, with no patients experiencing disease progression before surgery.     

Tumor necrosis factor alpha polymorphism C-850T is not associated with Alzheimer's disease and vascular dementia in an Italian population

A pathogenic role of inflammatory factors has been proposed both in Alzheimer's disease (AD) and vascular dementia (VD). A previous report indicated the presence of polymorphism C-850T of tumor necrosis factor (TNF) alpha as a genetic risk factor for VD and, associated with apolipoprotein E epsilon 4, for AD. We have assessed the association between TNF-alpha polymorphism and dementias in Italian populations of AD, VD and elderly controls. The influence of TNF-alpha polymorphism on dementia has not been confirmed in this segment of the Italian population.     

Nonlinear dynamics indicates aging affects variability during gait

OBJECTIVE: To investigate the nature of variability present in time series generated from gait parameters of two different age groups via a nonlinear analysis. DESIGN: Measures of nonlinear dynamics were used to compare kinematic parameters between elderly and young females. BACKGROUND: Aging may lead to changes in motor variability during walking, which may explain the large incidence of falls in the elderly. METHODS: Twenty females, 10 younger (20-37 yr) and 10 older (71-79 yr) walked on a treadmill for 30 consecutive gait cycles. Time series from selected kinematic parameters of the right lower extremity were analyzed using nonlinear dynamics. The largest Lyapunov exponent and the correlation dimension of all time series, and the largest Lyapunov exponent of the original time series surrogated were calculated. Standard deviations and coefficient of variations were also calculated for selected discrete points from each gait cycle. Independent t-tests were used for statistical comparisons. RESULTS: The Lyapunov exponents were found to be significantly different from their surrogate counterparts. This indicates that the fluctuations observed in the time series may reflect deterministic processes by the neuromuscular system. The elderly exhibited significantly larger Lyapunov exponents and correlation dimensions for all parameters evaluated indicating local instability. The linear measures indicated that the elderly demonstrated significantly higher variability. CONCLUSIONS: The nonlinear analysis revealed that fluctuations in the time series of certain gait parameters are not random but display a deterministic behavior. This behavior may degrade with physiologic aging resulting in local instability. RELEVANCE: Elderly show increased local instability or inability to compensate to the natural stride-to-stride variations present during locomotion. We hypothesized that this may be the one of the reasons for the increases in falling due to aging. Future efforts should attempt to evaluate this hypothesis by making comparisons to pathological subjects (i.e. elderly fallers), and examine the sensitivity and specificity of the nonlinear methods used in this study to aid clinical assessment.     

A randomized study of electronic mail versus telephone follow-up after emergency department visit

This study was conducted to determine whether electronic mail (e-mail) increases contact rates after patients are discharged from the emergency department (ED). Following discharge, patients were randomized to be contacted by telephone or e-mail. The main outcome was success of contact. Secondary outcome was the median time of response. There were 1561 patients initially screened. Of these, 444 had e-mail and were included in the study. Half were contacted by telephone and the rest via e-mail. Our telephone contact rate was 58% (129/222) after two calls in a 48-h period and our e-mail contact was 41% (90/222). The telephone was nearly two times better than e-mail. The median time of response was 48 h for e-mail and 18 h for telephone. It is concluded that the telephone is a better modality of contact than e-mail for patients discharged from the ED.     

Cardiocirculatory bio-assist: is it time to reconsider demand dynamic cardiomyoplasty? Review and future perspectives

In the last 15 years, dynamic cardiomyoplasty has remained an experimental procedure even after the enthusiastic short- and mid-term results, mainly because of the disappointing long-term outcome caused by muscular degeneration secondary to chronic continuous electrical stimulation of the latissimus dorsi. In Italy, a group of muscular pathologists, cardiologists, and cardiac surgeons conducted an experiment of an activity-rest stimulation protocol in humans that should avoid complete transformation of the skeletal muscle, maintaining its properties overtime. This "demand" stimulation protocol gave good results, improving New York Heart Association class, ejection fraction value, and survival. Even though dynamic cardiomyoplasty was excluded from the recent international guidelines for the management of heart failure, the discussion on the ability of this unique kind of cardiocirculatory bio-assistance is due to be reopened, thanks to the results of the new stimulation protocol. Heart transplantation, circulatory supporting devices, multisite stimulation therapy, and the total artificial heart are not always and in all countries the best solutions: the great economic cost, the numerous contraindications, the need for immunosuppression and antithrombotic therapy, and the troublesome follow up constitute important drawbacks. For patients in whom transplant surgery cannot be performed, as well as in developing countries, the nonprohibitively expensive demand dynamic cardiomyoplasty may still play a role.     

Laparoscopic wedge resection of a midsized gastrointestinal stromal tumor near the esophagogastric junction.

BACKGROUND: Gastrointestinal stromal tumors are rare neoplasms involving the entire digestive system, in particular the stomach. Generally, laparoscopic wedge resection is the preferred means of treating anterior lesions, while the preferred means of treating tumors in the posterior wall and near the esophagogastric junction remains controversial. CASE REPORT: We report the case of a patient with a gastric stromal tumor in the posterior wall of the greater curvature approximately 3 cm from the esophagogastric junction. Under intraoperative ultrasonic guidance, a large wedge resection was done using an ultrasonic scalpel; the gastric wall was reconstructed through a long intracorporeal suture. At 6-month follow-up, the patient was free from tumor recurrence. CONCLUSIONS: If a meticulous surgical technique is followed, laparoscopic wedge resection is a safe and feasible means of treating gastric stromal tumors in the posterior wall near the esophagogastric junction.