Quantitative and qualitative changes of plasma membrane glycoproteins in the early period of liver regeneration

Alterations of cell surface glycoconjugates have been observed in many developing systems and may be important in the physiological control of growth and differentiation. Liver regeneration after partial hepatectomy is a suitable model in which to study the regulatory mechanisms of cell proliferation in vivo. We have isolated the sinusoidal plasma membrane of hepatocytes at different times after partial hepatectomy. The sialic acid content and the SDS-polyacrylamide gel electrophoresis pattern of glycoproteins were determined. A decrease of periodic acid-Schiff-profiles, a change in the binding capacities of 125I-concanavalin A, a reduction of the sialic acid content and the appearance and disappearance of specific components have been observed during the pre-replicative phase of liver regeneration. These findings during this early period are consistent with the active involvement of the plasma membrane glycoproteins in the transition of cells to the proliferative state.     

Monitoring PCDD/Fs in Soil and Herbage Samples Collected Near a Hazardous Waste Incinerator: Health Risks for the Population Living Nearby

In 1998, we started a wide environmental surveillance program focused on evaluating the environmental impact of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) emitted by a new hazardous waste incinerator (HWI) (Tarragona County, Catalonia, Spain) and assessing the potential health risks for the population living nearby. The HWI began regular operations in 1999. Since then, periodical surveys have been performed. We report here the results concerning PCDD/F levels in 40 soil and 40 herbage samples collected in years 2004 and 2005, respectively, in the vicinity of the HWI. The human health risks derived from exposure to PCDD/Fs were also assessed. PCDD/F concentrations in soils ranged from 0.06 to 12.60 ng I-TEQ/kg, with median and mean values of 0.65 and 1.14 ng I-TEQ/kg, respectively. In herbage, PCDD/F concentrations ranged from 0.03 to 1.57 ng I-TEQ/kg, with median and mean values of 0.31 and 0.40 ng I-TEQ/kg, respectively. A comparison of these results with those from the baseline survey shows that, after six years of regular operation, the HWI did not significantly increase PCDD/F levels in soils and herbage in the surrounding environment. Moreover, PCDD/F emissions from the HWI do not mean additional significant risks for the health of the individuals living in the vicinity of the facility. The results of the current study together with those of recent investigations in municipal waste incinerators indicate that, when adequately controlled for PCDD/F emissions, modern waste incinerators should not portend any special concern for the populations living nearby.     

Acute toxicity and hematological and serum changes caused by various cobalt salts in rats

The acute toxicities of chloride, acetate, cobalt nitrate and cobalt sulphate (II) were investigated in rats. The values obtained for the LD50 (7 days) were 133, 194, 198 and 279 mg of Co/kg respectively, when the salts were given orally. The values for intraperitoneal administration were 10.6, 8.8, 8.3 and 11.5 mg of Co/kg. The majority of deaths occurred during the first 48 hours. The physical and clinical signs appearing after the intoxication disappeared for the most part after the first 72 hours. Also, the effect produced by chloride and cobalt acetate (II) given orally and intraperitoneally, in some hematological parameters and serum parameters during the first 24 hours after intoxications, has been studied at several doses. A noteworthy increase was observed in the hemoglobin and hematocrit as well as in the plasma proteins. There was significant hyperglycemia and also significant changes in the lipid parameters such as triglycerides and cholesterol. The duration and degree of the change depended on the dose. As a general rule, no significant differences were registered between the results obtained for the two salts.     

Long-Term Environmental Surveillance and Health Risks of Metals and PCDD/Fs Around a Cement Plant in Catalonia,Spain

In this study, environmental data concerning the potential impact of a cement plant were updated, 10 years after a previous monitoring study. In 2011 and 2012, samples of soil, vegetation, and air were collected in the vicinity of a cement plant located in Santa Margarida i els Monjos (Barcelona, Catalonia, Spain). The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and those of a number of metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Sn, Tl, V, and Zn) were determined. The results were compared with data from two previous sampling campaigns, performed in 2000 and 2001. Vanadium was the only element presenting a significant increase in the three monitors. In turn, a significant decrease of PCDD/Fs was noted in vegetation, from 0.2 to 0.1 ng WHO-TEQ/kg. The Hazard Quotient (HQ) of exposure to all pollutants was below the safety limit, while cancer risk associated with the exposure to metals and PCDD/Fs was within the range considered as assumable (10^?6–10^?4). Despite the long period of time elapsed between campaigns (10 years) and the use of alternative fuels, the impact of the cement plant seems to be low, based on the emissions of the contaminants here evaluated.     

Forest restoration is more than firing seeds from a drone

We are witnessing a rapid increase in news sending the message that drone seeding is a promising technological solution to implement forest restoration at large spatial scales. However, there are neither reports regarding success nor peer-reviewed studies to support these assertions. Once in the ground, the seeds and the seedlings and saplings that they generate have to face biotic and abiotic hazards that can strongly reduce regeneration potential. Successful forest restoration, therefore, cannot be achieved by simply dropping seeds from the air. We summarize some aspects to take into account before considering drone seeding as an efficient and widely applicable technology for forest restoration. A first step should be to increase the precision of drone seeding—contrary to the current massive firing of seeds—in order to concentrate the efforts in the best microsites for establishment and reduce the number of seeds needed and the cost of the whole operation.     

Effects of resistance training intensity on sleep quality and strength recovery in trained men: a randomized cross-over study

Resistance training (RT) variables can affect sleep quality, strength recovery and performance. The aim of this study was to examine the acute effect of RT leading to failure vs. non-failure on sleep quality (SQ), heart rate variability (HRV) overnight and one-repetition maximum (1-RM) performance 24 hours after training. Fifteen resistance-trained male athletes (age: 23.4 ± 2.4 years; height 178.0 ± 7.6 cm; weight: 78.2 ± 10.6 kg) performed two training sessions in a randomized order, leading to failure (4x10) or non-failure (5x8(10) repetitions), with 90 seconds for resting between sets at 75% 1-RM in bench press (BP) and half squat (HS). The day after, the participants completed the predicted 1-RM test for both exercises. In addition, the subjective and actigraphic SQ and HRV during sleep were measured after each training session. The day after the training protocol leading to failure, the 1-RM of BP (MD = 7.24 kg; -7.2%; p < 0.001) and HS (MD = 20.20 kg; -11.1%; p < 0.001) decreased. However, this parameter did not decrease after a non-failure RT session. No differences were observed between failure and non-failure training sessions on SQ and HRV; therefore, both types of training sessions similarly affected the SQ and the autonomic modulation during the night after the training session. This study provides an insight into the influence of different training strategies on SQ, strength performance and recovery after moderate- to high-demand training. This information could be useful especially for professional coaches, weightlifters and bodybuilders, due to the potential influence on the programming processes.