Intraspecies warfare restricts strain coexistence in human skin microbiomes.

Determining why only a fraction of encountered or applied bacterial strains engraft in a given person's microbiome is crucial for understanding and engineering these communities1. Previous work has established that metabolism can determine colonization success in vivo2-4, but relevance of bacterial warfare in preventing engraftment has been less explored. Here, we demonstrate that intraspecies warfare presents a significant barrier to strain transmission in the skin microbiome by profiling 14,884 pairwise interactions between Staphylococcus epidermidis cultured from eighteen human subjects from six families. We find that intraspecies antagonisms are abundant; these interactions are mechanistically diverse, independent of the relatedness between strains, and consistent with rapid evolution via horizontal gene transfer. Ability to antagonize more strains is associated with reaching a higher fraction of the on-person S. epidermidis community. Moreover, antagonisms are significantly depleted among strains residing on the same person relative to random assemblages. Two notable exceptions, in which bacteria evolved to become sensitive to antimicrobials found on the same host, are explained by mutations that provide phage resistance, contextualizing the importance of warfare among other lethal selective pressures. Taken together, our results emphasize that accounting for intraspecies bacterial warfare is essential to the design of long-lasting probiotic therapeutics.

Telemedicine and Socioeconomics in Orthopaedic Trauma Patients: A Quasi-Experimental Study During the COVID-19 Pandemic.

INTRODUCTION: Socioeconomic factors may introduce barriers to telemedicine care access. This study examines changes in clinic absenteeism for orthopaedic trauma patients after the introduction of a telemedicine postoperative follow-up option during the COVID-19 pandemic with attention to patient socioeconomic status (SES). METHODS: Patients (n = 1,060) undergoing surgical treatment of pelvic and extremity trauma were retrospectively assigned to preintervention and postintervention cohorts using a quasi-experimental design. The intervention is the April 2020 introduction of a telemedicine follow-up option for postoperative trauma care. The primary outcome was the missed visit rate (MVR) for postoperative appointments. We used Poisson regression models to estimate the relative change in MVR adjusting for patient age and sex. SES-based subgroup analysis was based on the Area Deprivation Index (ADI) according to home address. RESULTS: The pre-telemedicine group included 635 patients; the post-telemedicine group included 425 patients. The median MVR in the pre-telemedicine group was 28% (95% confidence interval [CI], 10% to 45%) and 24% (95% CI, 6% to 43%) in the post-telemedicine group. Low SES was associated with a 40% relative increase in MVR (95% CI, 17% to 67%, P < 0.001) compared with patients with high SES. Relative MVR changes between pre-telemedicine and post-telemedicine groups did not reach statistical significance in any socioeconomic strata (low ADI, -6%; 95% CI, -25% to 17%; P = 0.56; medium ADI, -18%; 95% CI, -35% to 2%; P = 0.07; high ADI, -12%; 95% CI, -28% to 7%; P = 0.20). CONCLUSIONS: Low SES was associated with a higher MVR both before and after the introduction of a telemedicine option. However, no evidence in this cohort demonstrated a change in absenteeism based on SES after the introduction of the telemedicine option. Clinicians should be reassured that there is no evidence that telemedicine introduces additional socioeconomic bias in postoperative orthopaedic trauma care. LEVEL OF EVIDENCE: III.

Syndesmotic Screw Breakage May Be More Problematic Than Previously Reported: Increased Rates of Hardware Removal Secondary to Pain With Intraosseous Screw Breakage.

BACKGROUND: The majority of retained syndesmotic screws will either loosen or break once the patient resumes weight-bearing. While evidence is limited, anecdotal experience suggests that intraosseous screw breakage may be problematic for some patients due to painful bony erosion. This study seeks to identify the incidence of intraosseous screw breakage, variables that may predict intraosseous screw breakage, and whether intraosseous screw breakage is associated with higher rates of implant removal secondary to pain. METHODS: Five hundred thirty-one patients undergoing syndesmotic stabilization were screened, of which 43 patients (with 58 screws) experiencing postoperative screw breakage met inclusion criteria. Patient charts were retrospectively reviewed for demographic data, comorbidities, time to screw breakage, location of screw breakage, and implant removal. Several radiographic parameters were evaluated for their potential to influence the site of screw breakage. RESULTS: Intraosseous screw breakage occurred in 32 patients (74.4%). Screw breakage occurred exclusively in the tibiofibular clear space in the remaining 11 instances (25.6%). Intraosseous screw breakage was significantly associated with eventual implant removal after breakage (P = .034). Screws placed further from the tibiotalar joint were at less risk for intraosseous breakage (odds ratio 0.818, P = .002). Screws placed at a threshold height of 20 mm or greater were more likely to break in the clear space (odds ratio 12.1, P = .002). CONCLUSION: Syndesmotic screw breakage may be more problematic than previously described. Intraosseous breakage was associated with higher rates of implant removal secondary to pain in this study. Placement of screws 20 mm or higher from the tibiotalar joint may decrease risk of intraosseous breakage.Levels of Evidence: Level III: Retrospective study.

Seed Biofortification by Engineered Nanomaterials: A Pathway To Alleviate Malnutrition?

Micronutrient deficiencies in global food chains are a significant cause of ill health around the world, particularly in developing countries. Agriculture is the primary source of nutrients required for sound health, and as the population has continued to grow, the agricultural sector has come under pressure to improve crop production, in terms of both quantity and quality, to meet the global demands for food security. The use of engineered nanomaterial (ENM) has emerged as a promising technology to sustainably improve the efficiency of current agricultural practices as well as overall crop productivity. One promising approach that has begun to receive attention is to use ENM as seed treatments to biofortify agricultural crop production and quality. This review highlights the current state of the science for this approach as well as critical knowledge gaps and research needs that must be overcome to optimize the sustainable application of nano-enabled seed fortification approaches.

Clinical Management of Arthrofibrosis: State of the Art and Therapeutic Outlook.

* Arthrofibrosis is a pathologic condition that is characterized by excessive periarticular scar-tissue formation. Arthrofibrosis may occur secondary to injury, surgical trauma, hemarthrosis, or infection, or it may occur idiopathically.* The pathogenesis of arthrofibrosis is incompletely understood but involves the dysregulation of normal reparative pathways, with transforming growth factor-beta (TGF-[beta]) as a principal mediator.* Current treatment options for arthrofibrosis primarily involve physiotherapy, operative manipulation, and surgical debridement, all with imperfect results.* Currently, there are no pharmacologic treatment options for arthrofibrosis. This has prompted increased investigational interest in the development of antifibrotic intra-articular therapies.

Nutritional Status of Tomato (Solanum lycopersicum) Fruit Grown in Fusarium-Infested Soil: Impact of Cerium Oxide Nanoparticles.

In this study, the impact of cerium oxide nanoparticles on the nutritional value of tomato (Solanum lycopersicum) fruit grown in soil infested with Fusarium oxysporum f. sp. lycopersici was investigated in a greenhouse pot study. Three-week old seedlings of Bonny Best tomato plants were exposed by foliar and soil routes to nanoparticle CeO2 (NP CeO2) and cerium acetate (CeAc) at 0, 50, and 250 mg/L and transplanted into pots containing a soil mixture infested with the Fusarium wilt pathogen. Fruit biomass, water content, diameter, and nutritional content (lycopene, reducing and total sugar) along with elemental composition, including Ce, were evaluated. Fruit Ce concentration was below the detection limit in all treatments. Foliar exposure to NP CeO2 at 250 increased the fruit dry weight (67%) and lycopene content (9%) in infested plants, compared with the infested untreated control. Foliar exposure to CeAc at 50 mg/L reduced fruit fresh weight (46%) and water content (46%) and increased the fruit lycopene content by 11% via root exposure as compared with the untreated infested control. At 250 mg/L, CeAc increased fruit dry weight (94%), compared with the infested untreated control. Total sugar content decreased in fruits of infested plants exposed via roots to NP CeO2 at 50 mg/kg (63%) and 250 mg/kg (54%), CeAc at 50 mg/kg (46%), and foliarly at 50 mg/L (50%) and 250 mg/L (50%), all compared with the infested untreated control. Plants grown in Fusarium-infested soil had decreased fruit dry weight (42%) and lycopene content (17%) and increased total sugar (60%) and Ca content (140%), when compared with the noninfested untreated control (p ≤ 0.05). Overall, the data suggested minimal negative effects of NP CeO2 on the nutritional value of tomato fruit while simultaneously suppressing Fusarium wilt disease.

High Burden of Associated Injuries Occurring With Major Fractures of the Talus.

BACKGROUND: Talus fractures are severe injuries typically occurring after high-energy trauma. As a result, associated injuries to different anatomic sites and organ systems occur with high frequency. The objective of this study was to determine what injuries occur with high incidence in patients presenting with major fractures of the talus and to identify clinical injury patterns that may warrant special attention in these patients. METHODS: We performed a retrospective review of patients presenting to 3 level 1 trauma centers with fractures of the talar neck, body, or head over a 14-year period. Patient charts were reviewed for associated orthopedic and nonorthopedic injuries identified during the initial patient encounter and hospitalization. RESULTS: In total, 262 fractures in 258 unique patients met criteria for inclusion. Overall, 33.3% of talus fractures occurred in isolation. One or more associated injuries were identified in the remainder of cases (66.7%). The incidence of associated injuries was similar across fracture patterns. Mean total number of injuries per patient was 2.2 (range, 0-15). The ipsilateral foot was the most frequent site of associated orthopedic injury. Noncontiguous injuries occurred in 36% of cases. Lumbar spine injury occurred in 10.5% of cases. Lower extremity vascular injury was uncommon but bore significant association with open talus fractures. CONCLUSION: Talus fractures are commonly associated with injuries to different anatomic sites and organ systems. A similar rate of lumbar spine trauma may occur with major talus fractures as has been historically associated with calcaneal fractures. Thorough evaluation and a high index of suspicion are necessary when evaluating patients with major fractures of the talus to avoid missing concomitant injuries. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Addition-omission of zinc, copper, and boron nano and bulk oxide particles demonstrate element and size -specific response of soybean to micronutrients exposure.

Plant response to microelements exposure can be modulated based on particle size. However, studies are lacking on the roles of particle size and specific microelements in mixed exposure systems designed for plant nutrition, rather than toxicology. Here, an addition-omission strategy was used to address particle-size and element-specific effects in soybean exposed to a mixture of nano and bulk scale oxide particles of Zn (2 mg Zn/kg), Cu (1 mg Cu/kg) and B (1 mg B/kg) in soil. Compared to the control, mixtures of oxide particles of both sizes significantly (p < 0.05) promoted grain yield and overall (shoot and grain) Zn accumulation, but suppressed overall P accumulation. However, the mixed nano-oxides, but not the mixed bulk-oxides, specifically stimulated shoot growth (47%), flower formation (63%), shoot biomass (34%), and shoot N (53%) and K (42%) accumulation. Compared by particle size, omission of individual elements from the mixtures evoked significant responses that were nano or bulk-specific, including shoot growth promotion (29%) by bulk-B; inhibition (51%) of flower formation by nano-Cu; stimulation (57%) of flower formation by bulk-B; grain yield suppression (40%) by nano-Zn; B uptake enhancement (34%) by bulk-Cu; P uptake stimulation by nano-Zn (14%) or bulk-B (21%); residual soil N (80%) and Zn (42%) enhancement by nano-Cu; and residual soil Cu enhancement by nano-Zn (72%) and nano-B (62%). Zn was responsible for driving the agronomic (biomass and grain yield) responses in this soil, with concurrent ramifications for environmental management (N and P) and human health (Zn nutrition). Overall, compared to bulk microelements, nanoscale microelements played a greater role in evoking plant responses.

ZnO nanoparticles increase photosynthetic pigments and decrease lipid peroxidation in soil grown cilantro (Coriandrum sativum).

The growth of the nanotechnology industry has raised concerns about its environmental impacts. In particular, the effect on terrestrial plants, which are the primary producers of the global food chain, is widely debated. In this study, cilantro plants (Coriandrum sativum) were cultivated for 35 days in soil amended with ZnO nanoparticles (N ZnO), bulk ZnO (B ZnO) and ZnCl2 (ionic/I Zn) at 0-400 mg/kg. Photosynthetic pigments, lipid peroxidation, 1NMR-based metabolic, and ICP-based metallomic profiles were evaluated. All Zn compounds increased the chlorophyll content by at least 50%, compared to control. Only N ZnO at 400 mg/kg decreased lipid peroxidation by 70%. 1NMR data showed that all compounds significantly changed the carbinolic-based compounds, compared with control. Highest root and shoot uptake of Zn was observed at B 400 and I 100, respectively. Results of this study corroborates that N ZnO at a concentration <400 mg/kg improved photosynthesis pigments and the defense response in cilantro plants cultivated in organic soil.

Finding the conditions for the beneficial use of ZnO nanoparticles towards plants-A review.

Zinc oxide nanoparticles (ZnO NPs) have a wide range of applications in cosmetics, electrical, and optical industries. The wide range of applications of ZnO NPs, especially in personal care products, suggest they can reach major environmental matrices causing unforeseen effects. Recent literature has shown conflicting findings regarding the beneficial or detrimental effects of ZnO NPs towards terrestrial biota. In this review we carried out a comprehensive survey about beneficial, as well as detrimental aspects, of the ZnO NPs exposure toward various terrestrial plants. A careful scrutiny of the literature indicates that at low concentrations (about 50 mg/kg), ZnO NPs have beneficial effects on plants. Conversely, at concentrations above 500 mg/kg they may have detrimental effects, unless there is a deficiency of Zn in the growing medium. This review also remarks the critical role of the biotic and abiotic factors that may elevate or ameliorate the impact of ZnO NPs in terrestrial plants.

Role of Cerium Compounds in Fusarium Wilt Suppression and Growth Enhancement in Tomato ( Solanum lycopersicum).

The use of nanoparticles in plant protection may reduce pesticide usage and contamination and increase food security. In this study, three-week-old Solanum lycopersicum seedlings were exposed, by root or foliar pathways, to CeO2 nanoparticles and cerium acetate at 50 and 250 mg/L prior to transplant into sterilized soil. One week later, the soil was inoculated with the fungal pathogen Fusarium oxysporum f. sp. lycopersici (1 g/kg), and the plants were cultivated to maturity in a greenhouse. Disease severity, biomass/yield, and biochemical and physiological parameters were analyzed in harvested plants. Disease severity was significantly reduced by 250 mg/L of nano-CeO2 and CeAc applied to the soil (53% and 35%, respectively) or foliage (57% and 41%, respectively), compared with non-treated infested controls. Overall, the findings show that nano-CeO2 has potential to suppress Fusarium wilt and improve the chlorophyll content in tomato plants.

Plant uptake and translocation of contaminants of emerging concern in soil.

The advent of industrialization has led to the discovery of a wide range of chemicals designed for multiple uses including plant protection. However, after use, most of the chemicals and their derivatives end up in soil and water, interacting with living organisms. Plants, which are primary producers, are intentionally or unintentionally exposed to several chemicals, serving as a vehicle for the transfer of products into the food chain. Although the exposure of pesticides towards plants has been witnessed over a long time in agricultural production, other chemicals have attracted attention very recently. In this review, we carried out a comprehensive overview of the plant uptake capacity of various contaminants of emerging concern (CEC) in soil, such as pesticides, polycyclic aromatic hydrocarbons, perfluorinated compounds, pharmaceutical and personal care products, and engineered nanomaterials. The uptake pathways and overall impacts of these chemicals are highlighted. According to the literature, bioaccumulation of CEC in the root part is higher than in aerial parts. Furthermore, various factors such as plant species, pollutant type, and microbial interactions influence the overall uptake. Lastly, environmental factors such as soil erosion and temperature can also affect the CEC bioavailability towards plants.

PARP1 and DNA-PKcs synergize to suppress p53 mutation and telomere fusions during T-lineage lymphomagenesis.

Poly(ADP-ribose) polymerase 1 (PARP1) interacts genetically with the DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress early-onset T-lineage lymphomas in the mouse, but the underlying mechanisms have remained unknown. To address this question, we analyzed a series of lymphomas arising in PARP1(-/-)/DNA-PKcs(-/-) (P1(-/-)/D(-/-)) mice. We found that, despite defective V(D)J recombination, P1(-/-)/D(-/-) lymphomas lacked clonal reciprocal translocations involving antigen-receptor loci. Instead, tumor cells were characterized by aneuploidy driven by two main mechanisms: p53 inactivation and abnormal chromosome disjunction due to telomere fusions (TFs). Aberrant accumulation of p53 was observed in 13/19 (68.4%) lymphomas. Sequence analysis revealed five p53 mutations: three missense point mutations (one transition in exon 8 and two transversions in exons 5 and 8, respectively), one in-frame 5-11 microindel in exon 7 and a 410-bp deletion encompassing exons 5-8, resulting in a truncated protein. Analysis of tumor metaphases using sequential telomere fluorescent in-situ hybridization and spectral karyotyping revealed that nine out of nine lymphomas contained TFs. Mutant but not wild-type p53 status was associated with frequent clonal and nonclonal TFs, suggesting that p53 normally limits the extent of telomere dysfunction during transformation. Chromosomes involved in TFs were more likely to be aneuploid than chromosomes not involved in TFs in the same metaphases, regardless of the p53 status, indicating that TFs promote aneuploidy via a mechanism that is distinct from p53 loss. Finally, analysis of radiation responses in P1(-/-)/D(-/-), and control primary cells and tissues indicates that loss of PARP1 increases in vivo radiosensitivity and genomic instability in DNA-PKcs-deficient mice without impairing p53 stabilization and effector functions, suggesting a more severe defect in double-strand break (DSB) repair in double mutants. Together, our findings uncover defective DSB repair leading to tumor suppressor inactivation and abnormal segregation of fused chromosomes as two novel mechanisms promoting tumorigenesis in thymocytes lacking PARP1 and DNA-PKcs.