Functional diversity and metabolic response in benthic communities along an ocean acidification gradient.

Altered ocean chemistry caused by ocean acidification (OA) is expected to have negative repercussions at different levels of the ecological hierarchy, starting from the individual and scaling up to the community and ultimately to the ecosystem level. Understanding the effects of OA on benthic organisms is of primary importance given their relevant ecological role in maintaining marine ecosystem functioning. The use of functional traits represents an effective technique to investigate how species adapt to altered environmental conditions and can be used to predict changes in the resilience of communities faced with stresses associated with climate change. Artificial supports were deployed for 1-y along a natural pH gradient in the shallow hydrothermal systems of the Bottaro crater near Panarea (Aeolian Archipelago, southern Tyrrhenian Sea), to explore changes in functional traits and metabolic rates of benthic communities and the repercussions in terms of functional diversity. Changes in community composition due to OA were accompanied by modifications in functional diversity. Altered conditions led to higher oxygen consumption in the acidified site and the selection of species with the functional traits needed to withstand OA. Calcification rate and reproduction were found to be the traits most affected by pH variations. A reduction in a community's functional evenness could potentially reduce its resilience to further environmental or anthropogenic stressors. These findings highlight the ability of the ecosystem to respond to climate change and provide insights into the modifications that can be expected given the predicted future pCO2 scenarios. Understanding the impact of climate change on functional diversity and thus on community functioning and stability is crucial if we are to predict changes in ecosystem vulnerability, especially in a context where OA occurs in combination with other environmental changes and anthropogenic stressors.

Use of irradiated PET plastic waste for partially replacing cement in concrete?

Portland cement used in the manufacture of concrete is responsible for an estimated 5-8% of the global CO2 emissions. Recently published work (Schaefer et al., 2018) claims that γ-irradiated PET waste powder can be used as a partial replacement of cement in concrete for reducing its CO2 footprint. More specifically, exposure of PET to γ-irradiation at a dosage of 100 kGy alters its crystal structure and chemical composition, which in turn leads to a smaller reduction in concrete strength compared to non-irradiated PET waste. Hence, making it possible for irradiated PET waste to be used as a raw ingredient in the manufacture of concrete while at the same time diverting significant quantities of PET waste from landfills. The aim of this research was to independently assess and verify the above claims. For this purpose, the effect of different low irradiation dosages (0, 10 and 100 kGy) and different replacement levels (2.5 %, 5 % and 10 % by volume) of cement by PET waste on the consistency and mechanical strength of pastes and mortars was determined in a laboratory investigation. XRD, TGA and DSC were also used to study the effect of irradiation on the microstructure of raw PET waste and the microstructure of paste and mortar samples containing irradiated PET waste powder. Our results indicate that use of γ-irradiated PET waste (exposed to an irradiation dosage of up to 100 kGy) for partially replacing cement does not lead to a significant recovery of mechanical strength lost when non-irradiated PET waste is used.

Re-do surgery after prosthetic abdominal wall repair: intraoperative findings of mesh-related complications.

INTRODUCTION: Mesh repair is one of the most popular technique for the treatment of abdominal wall hernias, resulting in lower recurrence rates. However, it is associated with a high risk of mesh-related complications. The aim of the present study is to assess the impact of biomaterials on the intra-abdominal organs, in terms of adhesions and visceral complications, in a series of patients undergoing re-do surgery at our abdominal wall unit. MATERIALS AND METHODS: We reviewed the clinical records of 301 patients who undergone laparotomy between June 2008 and May 2018, selecting 67 patients with one or more previous prosthetic abdominal wall repair (AWR). RESULTS: The average number of previous repairs was 1.6 with a mean time interval of 66 months from the last repair. Clinical presentation included hernia recurrence (69%), mesh infection (26%), infection and recurrence (10%), and fistula (1%). Adhesions were intraoperatively observed in all patients, except for eight cases. Mesh was completely removed in 43 patients, partially in four. Postoperative complications were observed in 39% of cases, including wound dehiscence, hematoma, seroma, and mesh infection. CONCLUSIONS: Long-term implant results in abdominal wall repair and are not completely known, and literature is still lacking on this topic. Re-do surgery for subsequent pathological events may represent a way to increase our knowledge.

A new semiresorbable mesh for primary inguinal repair: a preliminary observational study on quality of life and safety.

BACKGROUND: A currently unsolved problem of open inguinal hernia repair (IHR) is chronic postoperative inguinal pain (CPIP), which affects 10-12% of patients after IHR. In the present paper, we explored the results of a newly designed partially absorbable mesh made of polypropylene and polylactic acid (HybridMesh®) for open hernia repair and its impact on postoperative safety, efficacy, comfort and pain. METHODS: A prospective multicentric pilot trial was conducted in third-referral centers across Italy (n = 5). Inclusion criteria were unilateral primary inguinal hernia in patients of both genders and BMI < 30 kg/m2. All patients were submitted to elective Lichtenstein mesh hernia repair under local anesthesia with HybridMesh. Primary outcome measure was the evaluation of Carolina Comfort Scale and modifications at 2 years after surgery and its correlation with surgical variables; secondary outcomes were postoperative early and late morbidity, recurrence and postoperative early quality of life. RESULTS: Between 2015 and 2016, 125 (5 female) patients were operated, 2-year follow-up rate was 100%. The surgical site occurrence rate was 28% without the need of procedural interventions. Twenty-four months after surgery, no case of severe CPIP was recorded and altered global CCS score was present in 16 patients (13.0%). At univariate analysis, CCS score was negatively affected by fixation with sutures (OR 3.949; 95% CI 1.334-13.300), with no effect shown on multivariate analysis. Alterations in pain and movement limitations domains of CCS were observed in 9.7% of patients, at univariate analysis; they occurred more frequently when the mesh was sutured (OR 4.437; 95% CI 1.387-17.025) and in patients suffering from SSO (ecchymosis: OR 3.269; 95% CI 1.032-10.405); however, no effect was shown on multivariate analysis. Two recurrences (1.6%) were identified within the first postoperative year. CONCLUSIONS: The results of this study support the safety, efficacy and good tolerability of HybridMesh as a device to treat primary unilateral inguinal hernia during open anterior approach. Further studies are needed to clarify its role in comparison to currently available devices at longer follow-ups.

HIV infection and frequency of micronucleus in human peripheral blood cells.

PURPOSE: People living with HIV have higher rates of malignancies than the general population in the era of active antiretroviral therapy (ART). Genotoxic effects of HIV infection and/or ART that can induce neoplastic development are not yet well known. A prospective cohort study to investigate DNA damage measured through the micronuclei (MN) frequency in HIV-patients has been performed. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from 52 HIV-patients treated with ART and 55 healthy controls. RESULTS: By the comparison of MN frequency, a significant difference between HIV-patients (15.5 ± 9.8) and controls (6.0 ± 3.6) (p < 0.001) has been revealed. In univariate linear regression analysis, HCV infection (r = 0.31; p < 0.001), HIV-RNA (r = 0.29; p < 0.03) and duration of infection (r = - 0.16; p < 0.25) were associated with MN frequency; while only viral load (VL) significantly correlates (r = 0.29; p < 0.05) in a multiple regression model. CONCLUSIONS: The association of VL with MN frequency supports a genotoxic effect of HIV infection.

Functional diversity of free-living nematodes in river lagoons: can biological traits analysis (BTA) integrate traditional taxonomic-based approaches as a monitoring tool?

In four Po River lagoons, functional diversity of free-living nematodes was studied according to five biological traits (feeding type, life history, tail shape, body length and shape) considered singularly and combined in a Biological Traits Analysis (BTA). With the exception of 'Body length', similar distribution patterns were obtained for the other biological traits, considered singularly or in combination. From a functional point of view, the higher number of slender c-p3 selective deposit feeders with elongated tails rendered the assemblage in Marinetta-Vallona different from those in the other waterbodies where, by contrast, the nematodes were mainly represented by c-p2 non-selective deposit feeders with clavate tails and variable body lengths and shapes. On the contrary, the spatial patterns highlighted by genera data did not perfectly overlap with those identified by the biological traits. From a taxonomic point of view, the change ascribable to the higher abundance of Terschellingia in Marinetta-Vallona was comparable to those attributable to the other dominant genera (Sabatieria and Daptonema) in the other lagoons. Only the biological traits analysis was able to indicate that the dominance of Terschellingia in Marinetta-Vallona led also to a functional change within the assemblage. According to both functional and taxonomic approaches, the nematodes seemed influenced by polybrominated diphenyl ethers (ΣPBDEs), whose concentrations in the sediments clearly exceeded their toxicity thresholds in Marinetta-Vallona, suggesting, therefore, that this group of emerging pollutants might induce a nematodes response at both taxonomic and functional level. Our findings suggest that for scarcely biodiverse assemblages, such as those of river lagoons, the BTA may not provide further information than the analysis of single traits while both these functional approaches may add relevant ecological information to traditional taxonomic-based methods, representing therefore a potential integration in the use of nematodes in monitoring actions.

Mesh-related visceral complications following inguinal hernia repair: an emerging topic.

The use of meshes in inguinal hernia repair (IHR) has gained popularity but new complications have been observed. Mesh-related visceral complications (MRVCs) are generally considered rare and hence are not studied in depth. We carried out a thorough literature search and collected 101 clinical reports published from 1992 to 2018. The reported complications seem to have tripled in the last decade. Ninety-seven cases met the inclusion criteria and they were subdivided into four groups (group A-onlay IHR, group B-3-D IHR, group C-preperitoneal IHR, group D-laparoscopic IHR) to be analyzed, according to the herniorraphy technique. Every prosthetic IHR can be followed by MRVCs but, according to the present review, the highest incidence is related to laparoscopic repairs, the lowest to Lichtenstein technique. Time-to-event was shorter in case of preperitoneal position of the prosthesis than when the mesh was implanted over the transversalis fascia. Urinary bladder involvement predominantly occurred after laparosopic IHR. A pathogenic correlation between the most frequently complained clinical signs and the previous mesh herniorraphy was rarely reported. The diagnosis was generally made at laparotomy, which was usually performed as an emergency. Removing the infected mesh and resecting or suture repairing the involved viscera was the challenging surgical treatment. Prevention of MRVCs after inguinal hernia repair appears to be an important significant issue. It is important to pay attention to the choice of a proper implantation site, avoiding direct contact between the mesh and viscera, and to select a proper device.

Functional biodiversity of marine soft-sediment polychaetes from two Mediterranean coastal areas in relation to environmental stress.

Biological Traits Analysis (BTA) was used to identify functional features of infaunal polychaete assemblages associated with contamination in two Italian coastal areas: the harbour of Trieste (Adriatic Sea) and the Mar Piccolo of Taranto (Ionian Sea). The analysis was performed on 103 taxa, collected at four stations in each area. The two areas differed in species composition. The low diversity and the presence of stress-tolerant species in more polluted sites were not reflected in functional diversity, due to species contributing little to community functions or being functionally redundant. Sand and clay fractions were significant drivers of trait category expressions, however other environmental parameters (depth, total organic carbon and nitrogen, and Hg in sediments) influenced traits composition. Motile was the prevalent trait in environments with coarse sediments, and tube-builder were related to fine-grained ones. Motile, endobenthic and burrower were essential traits for living in contaminated sediments. Epibenthic and sessile polychaetes dominated at stations subjected to high organic loads. BTA offers an integrative approach to detect functional adaptations to contaminated sediments and multiple anthropogenic stressors.

Adhesion prevention in ventral hernia repair: an experimental study comparing three lightweight porous meshes recommended for intraperitoneal use.

BACKGROUND: In ventral hernia repair, when prosthetic material is placed intraperitoneally, it may lead to an inflammatory reaction resulting in adhesions between the mesh and abdominal viscera. Several meshes have been developed to minimize this process. In this experimental study, the ability of different combined meshes to attenuate the adhesion formation was examined. METHODS: Three commercially available lightweight porous combined meshes were placed intraperitoneally to repair an abdominal wall defect in rats: DynaMesh-IPOM (PVDF + PP), TiMesh (titanium-coated filament PP) and C-QUR/FX (omega-3 fatty acid-coated filament PP). The DynaMesh-CICAT (PVDF) was implanted in the control group. Adhesion formation was macroscopically evaluated and scored after 7 and 21 days. RESULTS: All animals except two presented intra-abdominal adhesions. None of the meshes examined in the study demonstrated to prevent adhesions. C-QUR/FX reduced adhesion formation at 7 days' follow-up compared with all other meshes but by 21 days this effect was diminished. Between 7 and 21 days adhesion extension significantly decreased for TiMesh. TAS did not show significant modifications between 7 and 21 days' follow-up for each mesh. CONCLUSIONS: The combined porous meshes tested in the present study demonstrated to reduce but not to prevent the adhesion formation, even if with some differences. Combined porous meshes could be chosen instead of simple meshes for retro-rectus preperitoneal prosthetic ventral hernia repair.

Benthic ecosystem functioning in the severely contaminated Mar Piccolo of Taranto (Ionian Sea, Italy): focus on heterotrophic pathways.

The benthic ecosystem functioning is a rarely applied holistic approach that integrates the main chemical and biological features of the benthic domain with the key processes responsible for the flux of energy and C through the system. For the first time, such conceptual model, with an emphasis on the heterotrophic pathways, has been applied to the sediments at four stations within one of the most polluted coastal areas in Italy: the Mar Piccolo of Taranto. The functioning of the benthic ecosystem was different according to the investigated site. Nearby the military arsenal, i.e., the main source of organic contaminants and heavy metals, the system seemed inhibited at all the investigated structural and functional levels. Slow microbial processes of C reworking together with very limited densities of benthic fauna suggested a modest transfer of C both into a solid microbial loop and to the higher trophic levels. On the other hand, the ingression of marine water through the "Navigabile" channel seemed to stimulate the organic matter degradation and, consequently, the proliferation of meiofauna and macrofauna. In the innermost part of the basin, the system functioning, to some extent, is less impacted by contaminants and more influenced by mussel farms. The organic matter produced by these bivalves fueled faster C reworking by benthic prokaryotes and enhanced the proliferation of filter feeders.

Microbial mechanisms coupling carbon and phosphorus cycles in phosphorus-limited northern Adriatic Sea.

The coastal northern Adriatic Sea receives pulsed inputs of riverine nutrients, causing phytoplankton blooms and seasonally sustained dissolved organic carbon (DOC) accumulation-hypothesized to cause episodes of massive mucilage. The underlying mechanisms regulating P and C cycles and their coupling are unclear. Extensive biogeochemical parameters, processes and community composition were measured in a 64-day mesocosms deployed off Piran, Slovenia. We followed the temporal trends of C and P fluxes in P-enriched (P+) and unenriched (P-) mesocosms. An intense diatom bloom developed then crashed; however, substantial primary production was maintained throughout, supported by tightly coupled P regeneration by bacteria and phytoplankton. Results provide novel insights on post-bloom C and P dynamics and mechanisms. 1) Post-bloom DOC accumulation to 186 µM remained elevated despite high bacterial carbon demand. Presumably, a large part of DOC accumulated due to the bacterial ectohydrolytic processing of primary productivity that adventitiously generated slow-to-degrade DOC; 2) bacteria heavily colonized post-bloom diatom aggregates, rendering them microscale hotspots of P regeneration due to locally intense bacterial ectohydrolase activities; 3) Pi turnover was rapid thus suggesting high P flux through the DOP pool (dissolved organic phosphorus) turnover; 4) Alpha- and Gamma-proteobacteria dominated the bacterial communities despite great differences of C and P pools and fluxes in both mesocosms. However, minor taxa showed dramatic changes in community compositions. Major OTUs were presumably generalists adapted to diverse productivity regimes.We suggest that variation in bacterial ectohydrolase activities on aggregates, regulating the rates of POM→DOM transition as well as dissolved polymer hydrolysis, could become a bottleneck in P regeneration. This could be another regulatory step, in addition to APase, in the microbial regulation of P cycle and the coupling between C and P cycles.

Hemoperitoneum: a rare complication of hemorrhoid treatment.

Pile suturing has always been used by surgeons to treat hemorrhoidal disease. We report a case of hemoperitoneum complicating a pile suture. Ultrasonography and computed tomography scan indicated the need for an emergency laparoscopic procedure and conservative management. As other authors have pointed out, we do not know how to prevent this type of complication. This case suggests the possibility of life-threatening complications following treatment procedures for hemorrhoids and underlines the importance of conservative treatment when this is possible.