Influence of nutrients addition and bioaugmentation on the hydrocarbon biodegradation of a chronically contaminated Antarctic soil

Complexity involved in the transport of soils and the restrictive legislation for the area makes on‐site bioremediation the strategy of choice to reduce hydrocarbons contamination in Antarctica. The effect of biostimulation (with N and P) and bioaugmentation (with two bacterial consortia and a mix of bacterial strains) was analysed by using microcosms set up on metal trays containing 2·5 kg of contaminated soil from Marambio Station. At the end of the assay (45 days), all biostimulated systems showed significant increases in total heterotrophic aerobic and hydrocarbon‐degrading bacterial counts. However, no differences were detected between bioaugmented and nonbioaugmented systems, except for J13 system which seemed to exert a negative effect on the natural bacterial flora. Hydrocarbons removal efficiencies agreed with changes in bacterial counts reaching 86 and 81% in M10 (bioaugmented) and CC (biostimulated only) systems. Results confirmed the feasibility of the application of bioremediation strategies to reduce hydrocarbon contamination in Antarctic soils and showed that, when soils are chronically contaminated, biostimulation is the best option. Bioaugmentation with hydrocarbon‐degrading bacteria at numbers comparable to the total heterotrophic aerobic counts showed by the natural microflora did not improve the process and showed that they would turn the procedure unnecessarily more complex.Fil: Ruberto, Lucas Adolfo Mauro. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Dias, Romina Laura. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lo Balbo, A.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Vázquez, Susana Claudia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Hernandez, E. A.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Mac Cormack, Walter Patricio. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Electrocardiographic Changes in Centenarians: A Study on 42 Subjects and Comparison with the Literature

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; Aging is associated with extensive and pervasive changes in cardiovascular structure and function, which may result in electrocardiographic alterations. The typical modifications seen in an electrocardiogram (ECG) in elders are: prolonged PR and QT intervals, QRS left-axis deviation and microvolt T wave. Several studies have included elderly people, but not long-living elderly and centenarians in particular who represent an increasing part of the population. &lt;b&gt;&lt;i&gt;Objective:&lt;/i&gt;&lt;/b&gt; The aim of this study was to investigate the electrocardiographic findings in a population of centenarians and to compare the results with the few studies present in the literature. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; We analyzed 42 healthy centenarians (12 males, 30 females; average age 101.43 ± 1.80 years) living in Messina, a municipality of Eastern Sicily, in Italy. They were clinically and functionally evaluated. All ECGs were analyzed by a single observer blind to clinical data. We assessed survival by phone recall. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; PR interval mean duration was 190 ± 3.3 ms, QRS 90 ± 1.4 ms, QTc interval mean duration was 370 ± 3.5 ms. Entirely normal ECG recordings were found in 7 centenarians (16.6%). The most frequently observed abnormalities included left-axis deviation and left anterior hemiblock in 16 centenarians (38.09%), left ventricular hypertrophy and aspecific ST-T wave abnormalities in 13 subjects (30.95%). We found no statistically significant differences between men and women. The mean age at death was 102.44 ± 2.45, and we did not find significant differences in age at death in long-living elderly in relation to different electrocardiographic findings. Comparing our results with two previous studies in the literature, the first conducted in Switzerland [Cornu: Rev Med Suisse Rom 1979;99:107–113] and the second in Nebraska [Lakkireddy et al.: Am J Cardiol 2003;92:1249–1251], we found a higher frequency of left ventricular hypertrophy that was compatible with the prevalence of hypertension in our centenarians (33.3%). Moreover, we did not find left bundle branch block, and the frequency of premature beats was remarkably less than that observed in the Swiss and US studies. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; Considering the increasing rate of centenarians, we believe that the results of the present study on electrocardiographic changes in centenarians may also be useful in clinical practice.</jats:p

Bioremediation of a petroleum hydrocarbon-contaminated Antarctic soil: Optimization of a biostimulation strategy using response-surface methodology (RSM)

Bioremediation is a biotechnological approach to clean up contaminated soils. Among bioremediation strategies, biostimulation is a simple method which involves the modification of the soil physicochemical conditions in order to enhance the biological degradation of contaminants. One of the most common ways to do this is by the addition of macronutrients, mainly Nitrogen (N) and Phosphorus (P). Optimization of the amounts of N and P for a soil biostimulation strategy represents a key step prior to its application to a full-scale process. In this work, the response-surface methodology (RSM) was applied to optimize a biostimulation process for a hydrocarbon-contaminated Antarctic soil, considering a Carbon:Nitrogen:Phosporus (C:N:P) ratio of 100:10:1 as a reference. A faced-centered central composite design was used to determine the levels of the variables that lead to the optimum response values. Flasks containing contaminated soil and receiving different N and P amounts were incubated at 15 °C for 80 days. Biological activity and hydrocarbon concentration were evaluated. Results predicted that for the soil used in this experiment, the addition of 0.183 g N/kg and 0.0179 g P/kg leads to the highest hydrocarbon removal efficiency. The resulting C:N:P ratio (100:17.6:1.73) was different from that taken as reference (100:10:1), highlighting the usefulness of such an optimization. The hydrocarbon concentration decreased from 1042 (± 73) mg kg− 1 to 470 (± 37) mg kg− 1 in the most efficient combination tested.Fil: Martinez Alvarez, Lucas Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Lo Balbo, A.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Mac Cormack, W.P.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Ruberto, Lucas Adolfo Mauro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentin

Bacterial community dynamics during bioremediation of diesel oil-contaminated antarctic soil

The effect of nutrient and inocula amendment in a bioremediation field trial using a nutrient-poor Antarctic soil chronically contaminated with hydrocarbons was tested. The analysis of the effects that the treatments caused in bacterial numbers and hydrocarbon removal was combined with the elucidation of the changes occurring on the bacterial community, by 16S rDNA-based terminal restriction fragment length polymorphism (T-RFLP) typing, and the detection of some of the genes involved in the catabolism of hydrocarbons. All treatments caused a significant increase in the number of bacteria able to grow on hydrocarbons and a significant decrease in the soil hydrocarbon content, as compared to the control. However, there were no significant differences between treatments. Comparison of the soil T-RFLP profiles indicated that there were changes in the structure and composition of bacterial communities during the bioremediation trial, although the communities in treated plots were highly similar irrespective of the treatment applied, and they had a similar temporal dynamics. These results showed that nutrient addition was the main factor contributing to the outcome of the bioremediation experiment. This was supported by the lack of evidence of the establishment of inoculated consortia in soils, since their characteristic electrophoretic peaks were only detectable in soil profiles at the beginning of the experiment. Genetic potential for naphthalene degradation, evidenced by detection of nahAc gene, was observed in all soil plots including the control. In treated plots, an increase in the detection of catechol degradation genes (nahH and catA) and in a key gene of denitrification (nosZ) was observed as well. These results indicate that treatments favored the degradation of aromatic hydrocarbons and probably stimulated denitrification, at least transiently. This mesocosm study shows that recovery of chronically contaminated Antarctic soils can be successfully accelerated using biostimulation with nutrients, and that this causes a change in the indigenous bacterial communities and in the genetic potential for hydrocarbon degradation

Transperitoneal versus extraperitoneal laparoscopic aortic lymph nodal staging for locally advanced cervical cancer: A systematic review and meta-analysis

Cervical cancer is the fourth most common neoplasm in women. In locally advanced cervical cancers, the international guidelines recommend nodal aortic assessment. Two techniques have been described to perform laparoscopic aortic lymphadenectomy: transperitoneal laparoscopic lymphadenectomy (TLL) and extraperitoneal laparoscopic lymphadenectomy (ELL). This meta-analysis aims to compare the surgical outcomes of TLL and ELL for staging purposes. The systematic review was carried out in agreement with the preferred reporting items for systematic reviews and meta-analyses statement (PRISMA). Two hundred and twenty studies were analyzed, and 19 studies were included in the review (7 for TLL and 12 for ELL group). 1112 patients were included in the analysis: 390 patients were included in group 1 and 722 patients in group 2.38 patients (9.7%) in the TLL group and 69 (9.5%) patients in the ELL group developed major complications. The analysis of all complications (intraoperative and postoperative) rate through pooled analysis did not show a significant difference between the two groups (p = 0.979), although a significantly higher intraoperative complication rate (p = 0.018) occurred in the TLL group compared to ELL. No significant differences were found between groups for BMI (p = 0.659), estimated blood loss (p = 0.889), length of stay (p = 0.932), intraoperative time (p = 0.932), conversion to laparotomy rate (p = 0.404), number of lymph node excised (p = 0.461) and postoperative complication (p = 0.291). TLL approach shows a higher rate of intraoperative complications, while no significant difference was found between the two techniques when postoperative complications were analyzed

Bacterial Community Dynamics during Bioremediation of Diesel-Oil Contaminated Antarctic Soil

The effect of nutrient and inocula amendment in a bioremediation field trial using a nutrient-poor Antarctic soil chronically contaminated with hydrocarbons was tested. The analysis of the effects that the treatments caused in bacterial numbers and hydrocarbon removal was combined with the elucidation of the changes occurring on the bacterial community, by 16S rDNA-based terminal restriction fragment length polymorphism (T-RFLP) typing, and the detection of some of the genes involved in the catabolism of hydrocarbons. All treatments caused a significant increase in the number of bacteria able to grow on hydrocarbons and a significant decrease in the soil hydrocarbon content, as compared to the control. However, there were no significant differences between treatments. Comparison of the soil T-RFLP profiles indicated that there were changes in the structure and composition of bacterial communities during the bioremediation trial, although the communities in treated plots were highly similar irrespective of the treatment applied, and they had a similar temporal dynamics. These results showed that nutrient addition was the main factor contributing to the outcome of the bioremediation experiment. This was supported by the lack of evidence of the establishment of inoculated consortia in soils, since their characteristic electrophoretic peaks were only detectable in soil profiles at the beginning of the experiment. Genetic potential for naphthalene degradation, evidenced by detection of nahAc gene, was observed in all soil plots including the control. In treated plots, an increase in the detection of catechol degradation genes (nahH and catA) and in a key gene of denitrification (nosZ) was observed as well. These results indicate that treatments favored the degradation of aromatic hydrocarbons and probably stimulated denitrification, at least transiently. This mesocosm study shows that recovery of chronically contaminated Antarctic soils can be successfully accelerated using biostimulation with nutrients, and that this causes a change in the indigenous bacterial communities and in the genetic potential for hydrocarbon degradation.(© 2008 Springer Science+Business Media, LLC.)This research was supported by grants from the Argentinean Antarctic Institute (IAA no. 42), the National Agency for Scientific and Technical Researches (PICTO 11555), and the University of Buenos Aires (UBACyT U007) as well as by a short-term travel fellowship from the Argentinean Research Council (CONICET). Research at the University of the Balearic Islands (UIB) was supported by grants VEM2003-20565 and CTM2005-01783 from the Spanish Ministry of Education and Science (MEC). B.N. was supported by a contract from the program “Ramón y Cajal” from MEC, and J.C-O by a fellowship of the Balearics Autonomous GovernmentPeer Reviewe