Marine microdebris pollution in sediments from three environmental coastal areas in the southwestern Argentine Atlantic.

Microplastics (MPs) and antifouling paint particles (APPs) are important components of marine microdebris (MDs), which constitute a potential environmental risk. This study analyzed baseline contamination levels of MDs and mesodebris (MesDs) in intertidal sediments at different depths, exploring the geomorphological influence in three Argentine coastal environments: Bahía Blanca Estuary (BBE), Los Pocitos (LP) and Puerto Madryn (PM). The MDs and MesDs samples were characterized by µ-FTIR, SEM/EDX and XRD. The abundance of MPs and APPs in sediments, range between 19.78 and 1087.19 and between 0 and 172.93 items/kg d.w., respectively. Despite variations in population and industrial developments in these areas, MPs abundance shows no significant differences in low and high intertidal zones. However, mean MPs concentrations were higher in the surface layer (0-5 cm) compared to the deeper sediments (5-10 cm), indicating recent MPs deposition. Chemical characterization evidenced the presence of cellulose (CE) and denser polymers as acrylonitrile butadiene styrene (ABS) and polyacrylics (PAN), APPs, metallic and black MDs. Surface degradation and heavy metals (Zn, Cr, and Ba) were also detected in APPs and other MDs, either as additives or adhered to their surfaces. Changes in crystallinity were also observed on the MesDs due to weathering. The calculated polymer hazard index (PHI) and the presence of hazardous polymers such as ABS and PAN indicated an increased risk of MPs pollution on the BBE and PM coasts. The pollution load index (PLI) values (from 4.63 to 5.34) suggested unpolluted to moderately polluted levels. These findings offer insights into potential risks associated with MDs in Argentine intertidal sediments, underscoring the critical need to comprehend the geomorphology and the influence of coastal dynamics. This is crucial for effectively addressing challenges linked to MDs pollution guiding the development of robust management and mitigation strategies.

HSP and apoptosis in leukocytes from infected or vaccinated animals by Brucella abortus.

The production of hsp and apoptosis of leukocytes in the peripheral blood of animals naturally infected with Brucella spp or treated with the vaccine Brucella abortus 19 have been investigated in this study. Cytokines able to induce phagocytic activity in macrophages of non treated healthy animals were found in the supernatant of bovine leukocytes cultivated in vitro. A long-lasting antibody response against hsp 60 kDa and 27 kDa, which lasts a long time, is induced in naturally infected animals, while in animals vaccinated with B. abortus 19 we detected an antibody response against hsp 60 and 70 kDa which is much shorter, disappearing in two months. During the early phase of infection, lymphocytes and monocytes of naturally infected animals show a delay of apoptosis in vitro compared to the same cells coming from healthy controls and vaccinated animals.

Phase I/II study of carboplatin and oral etoposide with granulocyte-colony stimulating factor in advanced nonsmall cell lung cancer.

BACKGROUND: A combination of carboplatin (CBDCA) and oral etoposide is better tolerated than, and as effective as, more aggressive chemotherapy regimens in patients with advanced nonsmall cell lung cancer (NSCLC). A Phase I/II study was conducted to determine whether the addition of the granulocyte-colony stimulating factor (G-CSF) allows the administration of higher doses of CBCDA. METHODS: The starting dose of CBDCA was 300 mg/m2 on day 1 every 28 days, in combination with a fixed dose of oral etoposide 50 mg/m2/day days 1-21, G-CSF (5 micrograms/ kg/day subcutaneously) was administered from day 7 until postnadir neutrophil count of more than 10,000/mm3, and from day 25 through day 28. RESULTS: From March 1991 to November 1993, 39 previously untreated patients with NSCLC (18 Stage IIIb and 21 Stage IV) entered this trial. Overall eight patients experienced dose-limiting toxicity in the first two courses. Five of them were older than 70 years. Age, CBDCA dose, CBDCA area under the curve (AUC), and performance status were correlated with severe neutropenia and thrombocytopenia, but carboplatin AUC was the only independent variable predictive of severity of both at multiple regression analysis. Thrombocytopenia was the major dose-limiting toxicity in this study. The maximum tolerated CBDCA dose and AUC were 600 mg/m2 and 8 respectively. No treatment-related death occurred. There was 1 (2.5%) complete response and 14 (36%) partial responses (overall response rate of 38.5%). AUC was more predictive of response achievement than carboplatin dose. Higher carboplatin dose and AUC were also associated with longer survival by univariate analysis, but by Cox regression analysis age was the only parameter independently predictive of survival. CONCLUSION: The administration of G-CSF permits safe escalation of CBDCA dose and AUC up to 600 mg/m2 and 8 respectively, in combination with a fixed dose of oral etoposide. Age older than 70 years represents a major obstacle to dose escalation. The increase of the body exposure to carboplatin seems to be associated with a better outcome. The determination of CBDCA AUC permits a better prediction of myelotoxicity and response rate.

Outbreaks of asthma attacks and meteorologic parameters in Bahia Blanca, Argentina.

Although Bahia Blanca is a relatively small city, the large daily number of asthmatic patients treated is comparable with cities at least ten times its population. A 1-year study of correlation between the daily cases treated and various meteorologic parameters is presented. Asthmatic outbreaks are normally associated with a dramatic decrease in temperature, humidity, and pressure. This condition may favor the activity of airborne allergenics transported mainly by continental winds.