Acidophilic heterotrophs: basic aspects and technological applications.

Acidophiles comprise a group of microorganisms adapted to live in acidic environments. Despite acidophiles are usually associated with an autotrophic metabolism, more than 80 microorganisms capable of utilizing organic matter have been isolated from natural and man-made environments. The ability to reduce soluble and insoluble iron compounds has been described for many of these species and may be harnessed to develop new or improved mining processes when oxidative bioleaching is ineffective. Similarly, as these microorganisms grow in highly acidic media and the chances of contamination are reduced by the low pH, they may be employed to implement robust fermentation processes. By conducting an extensive literature review, this work presents an updated view of basic aspects and technological applications in biomining, bioremediation, fermentation processes aimed at biopolymers production, microbial electrochemical systems, and the potential use of extremozymes.

Vortex ring beams in nonlinear P T-symmetric systems.

In this paper, we investigate a two-dimensional photonic array featuring a circular shape and an alternating gain and loss pattern. Our analysis revolves around determining the presence and resilience of optical ring modes with varying vorticity values. This investigation is conducted with respect to both the array's length and the strength of the non-Hermitian parameter. For larger values of the array's length, we observe a reduction in the stability domain as the non-Hermitian parameter increases. Interestingly, upon increasing the vorticity of the optical modes, full stability windows emerge for shorter lattice size regime.

Climate change increases threat to plant diversity in tropical forests of Central America and southern Mexico.

Global biodiversity is negatively affected by anthropogenic climate change. As species distributions shift due to increasing temperatures and precipitation fluctuations, many species face the risk of extinction. In this study, we explore the expected trend for plant species distributions in Central America and southern Mexico under two alternative Representative Concentration Pathways (RCPs) portraying moderate (RCP4.5) and severe (RCP8.5) increases in greenhouse gas emissions, combined with two species dispersal assumptions (limited and unlimited), for the 2061-2080 climate forecast. Using an ensemble approach employing three techniques to generate species distribution models, we classified 1924 plant species from the region's (sub)tropical forests according to IUCN Red List categories. To infer the spatial and taxonomic distribution of species' vulnerability under each scenario, we calculated the proportion of species in a threat category (Vulnerable, Endangered, Critically Endangered) at a pixel resolution of 30 arc seconds and by family. Our results show a high proportion (58-67%) of threatened species among the four experimental scenarios, with the highest proportion under RCP8.5 and limited dispersal. Threatened species were concentrated in montane areas and avoided lowland areas where conditions are likely to be increasingly inhospitable. Annual precipitation and diurnal temperature range were the main drivers of species' relative vulnerability. Our approach identifies strategic montane areas and taxa of conservation concern that merit urgent inclusion in management plans to improve climatic resilience in the Mesoamerican biodiversity hotspot. Such information is necessary to develop policies that prioritize vulnerable elements and mitigate threats to biodiversity under climate change.

Clinical study with sandblasted dental implants: a 17-year retrospective follow up.

Sandblasting is a standard procedure used for treating dental implant (DI) surfaces to enhance the osseointegration with known clinical success. This clinical study aimed to evaluate the long-term clinical outcomes of DIs with external hexagon connections and a surface sandblasted with calcium phosphate. Two hundred and seventy-five Mg-osseous™ (Mozo-Grau™) screw DIs were placed in 86 patients using a two-stage surgical technique and conventional loading protocol (at three months). Dental implants and prosthetic clinical findings were evaluated during a 17-year follow up. Four DIs were lost during the healing period, and 108 prostheses were placed over the 271 DIs left: 58 unitary implant-supported prosthesis (ISP), 31 partially ISP, 14 full-arch ISP, and five overdentures. Fourteen DIs were lost during the follow-up period. Clinical results indicated a DI survival rate of 93.50%. A total of 11.80% of DIs showed peri-implantitis as the primary biological complication. The mean (SD) marginal bone loss was 1.78 (0.40) mm, ranging from 0.90 to 2.80 mm. The most frequent complication was mechanical prosthodontic complications (24.40%). Sandblasted surface DIs inserted in both maxillary and mandibular areas produce favourable long-term (17-year follow up) outcomes and stable tissue conditions when a delayed loading protocol is followed.

MicroRNA-512-3p mediates Trypanosoma cruzi-induced apoptosis during ex vivo infection of human placental explants.

INTRODUCTION: Upon infection, Trypanosoma cruzi, a protozoan parasite, crosses the placental barrier and causes congenital Chagas disease. Ex vivo infection of human placental explants (HPEs) with the parasite induces apoptotic cell death. This cellular process involves changes in gene expression, which are partially regulated by miRNAs. In this study, we investigated the role of miR-512-3p, a highly expressed miRNA in the placenta, in parasite-induced apoptosis. METHODS: HPE cells were transfected with antagomirs or mimics of miR-512-3p and subsequently challenged with the parasite. The expression levels of miR-512-3p, caspase 3, caspase 8, and Livin were measured using RT-qPCR, and apoptotic cell death was analyzed based on caspase activity and DNA fragmentation assays. RESULTS: Targeted inhibition of miR-512-3p effectively prevented parasite-induced expression and enzymatic activity of caspase 3 and caspase 8. However, it did not completely prevent DNA fragmentation, indicating the involvement of other factors in this process. Furthermore, the findings suggest that Livin may be regulated by miR-512-3p. DISCUSSION: Our findings suggest that miR-512-3p modulates parasite-induced apoptosis in the trophoblast. By understanding the mechanisms involved in this process, we can gain insights into the pathogenesis of congenital Chagas disease and develop targeted therapeutic strategies.

Immediate Loading of Implants with Fixed Rehabilitations in Geriatric Edentulous Patients; Biological Complications.

BACKGROUND: This study aimed to report the outcomes of the immediate loading of implants with fixed rehabilitations in edentulous geriatric patients. METHODS: Edentulous geriatric patients were diagnosed with an oral examination, radiographic evaluation, and intermaxillary relations and treated with fixed rehabilitation over several implants. After immediate surgery, the implants were immediately loaded with a fully fixed prosthesis. RESULTS: Twenty-four patients (20 females and 4 males) were treated using a total 210 implants. All patients (100%) had a previous history of periodontitis. Eleven patients (45.8%) were smokers. Eleven patients (45.8%) suffered from chronic medical diseases (i.e., diabetes, cardiovascular diseases). The study's clinical follow-up period extended for three years, during which thirty-three fixed prostheses were installed over the implants in 24 patients. The average marginal bone loss measured was 1.33 ± 0.17 mm. The success rate of the implants and prosthodontics being placed in this study yielded 98.5% and 97%, respectively. One patient (4.2%) showed some kind of technical complications. Eleven patients (45.8%) showed mucositis, and 25 implants (11.9%) in 10 patients (41.7%) were associated with peri-implantitis. CONCLUSIONS: This study shows that the treatment of edentulous geriatric patients by immediate loading of implants with fixed rehabilitations is a clinically successful protocol but with a high prevalence of peri-implant diseases.

Climate change as a driver of insect invasions: Dispersal patterns of a dragonfly species colonizing a new region.

The dragonfly Trithemis kirbyi Sélys, 1891 recently colonized Western Europe from North Africa. Since its first record in the Iberian Peninsula in 2007, the species has been spreading northward and has become naturally established in the central and eastern Iberian Peninsula, the Balearic Islands and southern France. Despite its worldwide distribution, its rapid colonization of the western Mediterranean area occurred only very recently. The aims of this study were to evaluate (1) whether the species' colonization of the western Mediterranean is related to climate change and rising temperatures, specifically the summer warming peaks that have occurred in the last decade, (2) which climatic variables have most influenced its distribution and dispersal, and (3) its potential future dispersal and colonization capacity towards the eastern Mediterranean. We found that the dispersal and recent establishment of T. kirbyi in southwestern Europe strongly depends on increasing temperatures, particularly summer temperature peaks, which has allowed this species to disperse farther and more effectively than during years with average summer temperatures. The most important variable in the suitability models is the minimum temperature of the coldest month, which, in recent decades, has become less of a limiting factor for ectotherms. According to the models, suitable areas for the species are currently found throughout the eastern Mediterranean parts of Europe, and it is likely that it can naturally colonize these areas as it did in the Iberian Peninsula. Trithemis kirbyi is a model of how climate change and observed rising temperatures have turned previously inhospitable regions into suitable areas for exotic species, which may successfully colonize them naturally if they can reach these promising lands on their own. However, this study serves as a warning that such species can also colonize these new regions with a little help from unsuspecting means, which are often responsible for the increasingly common presence of invasive, noxious taxa in Europe.

Early Loading of Two Implants Supporting Mandibular Overdentures in Geriatric Edentulous Patients: A 12-Year Follow-Up Study.

Background: This study aims to show the clinical outcomes of implants supporting mandibular overdentures in edentulous patients. Methods: Mandibular edentulous patients were diagnosed with an oral examination, panoramic radiograph, and diagnostic casts for intermaxillary relations and treated with overdentures over two implants. After two-stage surgery, implants were early loaded with an overdenture at 6 weeks. Results: Fifty-four patients (28 females and 24 males) were treated with 108 implants. Thirty-two patients (59.2%) had a previous history of periodontitis. Twenty-three patients (46%) were smokers. Forty patients (74.1%) suffered from systemic diseases (i.e., diabetes, cardiovascular diseases). The clinical follow-up of the study was 147.8 ± 10.4 months. The clinical outcomes showed a global success of 94.5% of implants. Fifty-four overdentures were placed in the patients over the implants. The mean marginal bone loss was 1.12 ± 0.34 mm. Nineteen patients (35.2%) showed some kind of mechanical prosthodontic complication. Sixteen implants (14.8%) were associated with peri-implantitis. Conclusions: Based on the clinical results obtained, we can determine that the treatment of elderly edentulous patients with mandibular overdentures through the early loading of two placed implants is a successful implant protocol.

Relevant Aspects of Titanium Topography for Osteoblastic Adhesion and Inhibition of Bacterial Colonization.

The influence of the surface topography of dental implants has been studied to optimize titanium surfaces in order to improve osseointegration. Different techniques can be used to obtain rough titanium, however, their effect on wettability, surface energy, as well as bacterial and cell adhesion and differentiation has not been studied deeply. Two-hundred disks made of grade 4 titanium were subjected to different treatments: machined titanium (MACH), acid-attacked titanium (AE), titanium sprayed with abrasive alumina particles under pressure (GBLAST), and titanium that has been treated with GBLAST and then subjected to AE (GBLAST + AE). The roughness of the different treatments was determined by confocal microscopy, and the wettability was determined by the sessile drop technique; then, the surface energy of each treatment was calculated. Osteoblast-like cells (SaOs-2) were cultured, and alkaline phosphatase was determined using a colorimetric test. Likewise, bacterial strains S. gordonii, S. oralis, A. viscosus, and E. faecalis were cultured, and proliferation on the different surfaces was determined. It could be observed that the roughness of the GBLAST and GBLAS + AE was higher, at 1.99 and 2.13 µm of Ra, with respect to the AE and MACH samples, which were 0.35 and 0.20 µm, respectively. The abrasive treated surfaces showed lower hydrophilicity but lower surface energy. Significant differences could be seen at 21 days between SaOS-2 osteoblastic cell adhesion for the blasted ones and higher osteocalcin levels. However, no significant differences in terms of bacterial proliferation were observed between the four surfaces studied, demonstrating the insensitivity of bacteria to topography. These results may help in the search for the best topographies for osteoblast behavior and for the inhibition of bacterial colonization.

Prosthetic rehabilitation after hemimaxillectomy: a case report.

Maxillofacial defects created by the surgical resection of a tumor negatively impact the mastication, phonation, swallowing, and psychological function of patients. A 68-year-old woman received a diagnosis of oral squamous cell carcinoma involving the hard palate. The hemimaxillectomy procedure for tumor resection created a defect on the left side of the palate. This case report describes the patient's cancer treatment from presurgical planning to final rehabilitation with a conventional obturator and subsequent follow-up care for 1 year. The rehabilitation strategy was satisfactory for the patient, reestablishing lost function and esthetics.

State of the Oral Implantology Practice in Spain during the COVID-19 Pandemic: A Cross-Sectional Survey.

At the beginning of the COVID-19 pandemic, strict measures of confinement and social distancing were taken. Dentists were considered essential personnel and their activity was restricted to emergency treatment. The present observational study aims to determine the situation of oral implantology practice in Spain during the initial period of the COVID-19 pandemic. This is a cross-sectional observational study based on the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines. An electronic survey consisting of three blocks of questions was sent to all members of the Spanish Society of Implants. The data were analyzed using descriptive analysis. A total of 237 participants (14.3%) responded to the questionnaire. The majority of participants (60.8%) only attended emergencies during the first 9 months of the pandemic. Despite this, 77.2% reported having performed dental implant surgeries and 75.5% indicated that they performed non-essential treatments. The activity was fully recovered by 64.1% of the surveyed dentists. The majority of dentists (90.7%) considered that sufficient/adequate preventive measures were carried out at their workplace, which possibly contributed to the fact that 49.3% were not afraid of becoming infected. This concern was significantly and directly proportionally associated with the age of the surveyed dentists. The oral implant practice was affected to a greater extent during the first 9 months of the pandemic, especially in urban areas, with a greater impact on the workload of professionals with less specialised training in oral implantology.

The performance of protected-area expansions in representing tropical Andean species: past trends and climate change prospects.

Protected area (PA) extent has increased significantly over the last 150 years globally, but it is yet unclear whether progress in expanding coverage has been accompanied by improved performance in ecological representation. Here, we explore temporal trends in the performance of PA networks in representing > 16,000 vertebrate and plant species in tropical Andean countries based on species bioclimatic niche modelling. We use a randomization analysis to assess whether representation gains over time (1937-2015) are the expected consequence of increasing the overall area of the network or the result of better designed networks. We also explore the impact of climate change on protected-area representation based on projected species distributions in 2070. We found that PAs added in the last three to four decades were better at representing species diversity than random additions overall. Threatened species, amphibians and reptiles are the exception. Species representation is projected to decrease across PAs under climate change, although PA expansions over the last decade (2006-2015) better represented species' future bioclimatic niches than did sites selected at random for most evaluated groups. These findings indicate an unbalanced representation across taxa, and raises concern over under-represented groups, including threatened species, and species' representation under climate change scenarios. However, they also suggest that decisions related to locating protected areas have become more strategic in recent decades and illustrate that indicators tracking representativeness of networks are crucial in PA monitoring frameworks.

Mass Poisoning From Ethylene Glycol at a U.S. Military Base.

Ethylene glycol (EG) toxicity is an important cause of toxic alcohol poisoning in the USA with over 5,000 exposures reported annually. While classically characterized by solitary accidental or intentional ingestions, mass toxic alcohol poisoning outbreaks and more rarely collective consumptions (typically of methanol) have been described. We describe an ethylene glycol poisoning from collective ingestion that involved soldiers presenting at William Beaumont Army Medical Center in El Paso, Texas. Eleven soldiers presented to the emergency department over a 12-h period after ingestion of an unknown substance. The first two patients exhibited severe neurologic symptoms, while the remainder were asymptomatic. As serum EG levels were not immediately available, treatment decisions were based on surrogate laboratory values. Two patients received immediate hemodialysis, and fomepizole (FOM) because of severe acidosis with elevated anion and osmolal gaps. These patients developed acute kidney injury with renal recovery within a 3-week period. Two patients with elevated lactate received bicarbonate-based intravenous (IV) fluids and FOM. Two patients received IV fluids only and required prolonged observation for worsening acidosis and/or acute kidney injury. Five patients with normal laboratory values were treated with IV fluids and observation. All patients received cofactors including thiamine and pyridoxine. All patients survived. The outbreak occurred in the setting of limited dialysis resources, limited FOM availability, and in a resource-limited community. Additional guidelines are needed to determine allocation of limited resources, optimal dialysis and FOM treatment course, and comorbid conditions, which may prolong recovery.

Silver coating on dental implant-abutment connection screws as potential strategy to prevent loosening and minimizing bacteria adhesion.

Introduction: One of the main problems for the long-term behavior of dental implants are loosening of the implant-abutment connection screws and bacterial infiltration. The aim of this work is to increase the screw fixation by silver coating, providing superior mechanical retaining and antibacterial effect. Methods: Eighty dental implants with their abutments and screws have been studied. Twenty screws were not coated and were used as a control while the rest of screws were silver coated by sputtering, with three different thickness: 10, 20 and 40 µm and 20 screws per each thickness. Coating morphology and thickness were determined by scanning electron microscopy using image analysis systems. The screws were tightened for each of the thicknesses and the control with two torques 15 Ncm and 20 Ncm and tested under mechanical fatigue simulating oral stresses up to a maximum of 500,000 cycles. The remaining torques at different cycles were determined with a high-sensitivity torquemeter. Cell viability assays were performed with SaOs-2 osteoblasts and microbiological studies were performed against Streptococcus gordonii and Enterococcus faecalis bacteria strains, determining their metabolic activity and viability using live/dead staining. Results: It was observed a decrease in torque as cycles increase. For a preload of 15 Ncm at 100,000 cycles, the loosening was complete and, for 20 Ncm at 500,000 cycles, 85% of torque was lost. The silver coatings retained the torque, especially the one with a thickness of 40 µm, retaining 90% of the initial torque at 500,000 cycles. It was observed that osteoblastic viability values did not reach 70%, which could indicate a slight cytotoxic effect in contact with cells or tissues; however, the screw should not be in direct contact with tissue or living cells. Silver coating induced a significant reduction of the bacteria metabolic activity for Streptococcus gordonii and Enterococcus faecalis, around 90% and 85% respectively. Discussion: Therefore, this coating may be of interest to prevent loosening of implant systems with a worthy antibacterial response.

Immediate Functional Loading with Full-Arch Fixed Implant-Retained Rehabilitation in Periodontal Patients: Clinical Study.

(1) Background. The immediate functional loading of implants is a clinical procedure used for treating periodontal edentulous patients. This clinical study aimed to evaluate the clinical outcomes of the immediate functional loading of implants with fully fixed rehabilitations in compromised periodontal patients. (2) Methods. Three hundred and five implants IPX screw implants were placed in 27 periodontal patients using an immediate functional loading protocol with fixed rehabilitations. All patients had a previous history of periodontitis, four patients (14.8%) were smokers and seven patients (25.9%) suffered from chronic medical conditions. (3) Results. Implant and prosthetic clinical findings were evaluated during a mean period of 41.3 ± 19.6 months. No implants were lost during the clinical follow-up. The cumulative survival rate for all implants was 100%. Regarding the prostheses designed, a total of 54 fixed prostheses were placed in the 27 patients immediately after the surgery. Forty-four hybrid fixed prostheses (81.5%) and 10 fixed rehabilitations (18.5%) were placed in the patients. The mean marginal bone loss was 1.51 ± 1.16 mm, ranging from 0 to 3.5 mm during the follow-up evaluation. Thirty-one implants (10.2%) in 10 patients (37%) were associated with peri-implantitis. Five patients (18.5%) showed some kind of technical complications (loss/fracture of the prosthetic screw, acrylic resin fracture, ceramic chipping). (4) Conclusions. The clinical outcomes of this study demonstrate that fixed rehabilitation by immediate functional loading of implants is considered a predictable procedure.

Differential microRNAs expression during ex vivo infection of canine and ovine placental explants with Trypanosoma cruzi and Toxoplasma gondii.

Trypanosoma cruzi and Toxoplasma gondii are two zoonotic parasites that constitute significant human and animal health threats, causing a significant economic burden worldwide. Both parasites can be transmitted congenitally, but transmission rates for T. gondii are high, contrary to what has been observed for T. cruzi. The probability of congenital transmission depends on complex interactions between the pathogen and the host, including the modulation of host cell gene expression by miRNAs. During ex vivo infection of canine and ovine placental explants, we evaluated the expression of 3 miRNAs (miR-30e-3p, miR-3074-5p, and miR-127-3p) previously associated with parasitic and placental diseases and modulated by both parasites. In addition, we identified the possible target genes of the miRNAs by using computational prediction tools and performed GO and KEGG enrichment analyses to identify the biological functions and associated pathologies. The three miRNAs are differentially expressed in the canine and ovine placenta in response to T. cruzi and T. gondii. We conclude that the observed differential expression and associated functions might explain, at least partially, the differences in transmission rates and susceptibility to parasite infection in different species.