Recipient Environment Research Articles

The Time Has Come: The Case for Initiating Pilot Clinical Trials of Pig Kidney Xenotransplantation.

In vitro studies indicate that kidney transplantation from gene-edited pigs in which expression of all three of the known glycan xenoantigens has been deleted may be more challenging in nonhuman primates (NHPs) than it will be in human recipients. Furthermore, pig-to-human xenotransplantation offers several other advantages - (i) the patient can communicate with the surgical team; (ii) recipient microbiological monitoring and environment will be clinical-grade; and (iii) sophisticated graft monitoring and imaging techniques, (v) therapeutic interventions, e.g., dialysis, plasmapheresis, and (v) intensive care can be deployed that are not easily available in NHP laboratory models. We suggest, therefore, that progress to develop safe, informative human clinical trials will be accelerated if pilot clinical cases are initiated. The selection of patients for kidney xenotransplantation can include those who are at high risk of dying imminently, e.g., those experiencing increasing vascular access challenges with no realistic alternative therapy available, and those who have been accepted onto the waitlist for an allograft, but who are unlikely ever to receive one. Patients with an increased risk of dying include those with (i) age >60 years, (ii) blood groups O or B, and (iii) diabetic nephropathy. UNOS data indicate that an average of 25 patients on the kidney waitlist in the USA die or are removed from the list every day (i.e., >9,000 each year). Given the improved xenograft survival observed in preclinical studies, we suggest that it is time to plan a small pilot clinical trial for healthy dialysis patients who understand the risks and potential benefits of kidney xenotransplantation.

The Myofibroblast Fate of Therapeutic Mesenchymal Stromal Cells: Regeneration, Repair, or Despair?

Mesenchymal stromal cells (MSCs) can be isolated from various tissues of healthy or patient donors to be retransplanted in cell therapies. Because the number of MSCs obtained from biopsies is typically too low for direct clinical application, MSC expansion in cell culture is required. However, ex vivo amplification often reduces the desired MSC regenerative potential and enhances undesired traits, such as activation into fibrogenic myofibroblasts. Transiently activated myofibroblasts restore tissue integrity after organ injury by producing and contracting extracellular matrix into scar tissue. In contrast, persistent myofibroblasts cause excessive scarring-called fibrosis-that destroys organ function. In this review, we focus on the relevance and molecular mechanisms of myofibroblast activation upon contact with stiff cell culture plastic or recipient scar tissue, such as hypertrophic scars of large skin burns. We discuss cell mechanoperception mechanisms such as integrins and stretch-activated channels, mechanotransduction through the contractile actin cytoskeleton, and conversion of mechanical signals into transcriptional programs via mechanosensitive co-transcription factors, such as YAP, TAZ, and MRTF. We further elaborate how prolonged mechanical stress can create persistent myofibroblast memory by direct mechanotransduction to the nucleus that can evoke lasting epigenetic modifications at the DNA level, such as histone methylation and acetylation. We conclude by projecting how cell culture mechanics can be modulated to generate MSCs, which epigenetically protected against myofibroblast activation and transport desired regeneration potential to the recipient tissue environment in clinical therapies.

Leveraging aquatic-terrestrial interfaces to capture putative habitat generalists.

Habitat type is a strong determinant of microbial composition. Habitat interfaces, such as the boundary between aquatic and terrestrial systems, present unique combinations of abiotic factors for microorganisms to contend with. Aside from the spillover of certain harmful microorganisms from agricultural soils into water (e.g. fecal coliform bacteria), we know little about the extent of soil-water habitat switching across microbial taxa. In this study, we developed a proof-of-concept system to facilitate the capture of putatively generalist microorganisms that can colonize and persist in both soil and river water. We aimed to examine the phylogenetic breadth of putative habitat switchers and how this varies across different source environments. Microbial composition was primarily driven by recipient environment type, with the strongest phylogenetic signal seen at the order level for river water colonizers. We also identified more microorganisms colonizing river water when soil was collected from a habitat interface (i.e. soil at the side of an intermittently flooded river, compared to soil collected further from water sources), suggesting that environmental interfaces could be important reservoirs of microbial habitat generalists. Continued development of experimental systems that actively capture microorganisms that thrive in divergent habitats could serve as a powerful tool for identifying and assessing the ecological distribution of microbial generalists.

Surveillance of SARS-CoV-2 RNA in wastewater matrix: a review.

SARS-CoV-2 is the agent responsible for the global pandemic sickness, COVID-19. It is an enveloped virus that belongs to the family Coronaviridae. Recent studies have revealed the fecal shedding of the virus and have been found to enter wastewater and aquatic systems. Prolonged viral presence in fecal samples is a common observation in the reported literature. Survival of the virus in the recipient environment could be a crucial factor that influences its fecal-oral transmission. The detection of a novel coronavirus in wastewater opportunity has potential for environmental surveillance at the community or population level. Such a surveillance system can enable the early detection of disease outbreaks in zones with pre-symptomatic/asymptomatic patients and act as a complementary tool for continuous monitoring of quarantine zones. In contrast to developed regions, resource constraints in underdeveloped communities coupled with different sanitation settings may pose a challenge to wastewater sampling and surveillance. To begin, this review summarizes the literature on the presence of SARS-CoV-2 in feces. The approaches for viral extraction, concentration, and detection in wastewater matrices are then highlighted. Finally, investigations on wastewater-based epidemiology for SARS-CoV-2 surveillance are reviewed.

Shear Enhanced Flotation Separation Technology in Winery Wastewater Treatment

The process of wine making is well known to produce large amounts of wastewater with highly variable characteristics. The disposal of untreated winery wastewater is strictly prohibited since it adversely affects the recipient environment. Due to the variability in characteristics of winery wastewater, developing a treatment system which can handle high organic and inorganic loads, especially during the vintage season, is a complex challenge. This study investigated the theory, methodology and implementation of a wastewater treatment technology called shear enhanced flotation separation (SEFS) as a potential primary treatment stage towards the treatment of winery wastewater. Winery effluent was subjected to a coagulation process in a high shear environment, with and without the introduction of air, followed by flocculation. Upon successful optimization of operating parameters, a polymeric-based coagulant AB121 and polyelectrolyte flocculant AB796 yielded the highest reduction in turbidity (95%) with typical values of 630 NTU for the raw wastewater and 25 NTU for the SEFS-treated effluent. A substantial reduction in total suspended solids (97%) was achieved with average raw winery wastewater values of 2275 mg/L compared to the 50 mg/L obtained for the SEFS-treated effluent. Furthermore, a notable reduction (54%) in COD (from 11,250 mg/L to 5220 mg/L) using SEFS technology was achieved.

Toxicity Assessment of Produced Water Using Nitrosomonas sp.

Aim: Most studies on the effect of produced water are centred on the effects on the physicochemical parameters of the recipient environment, but not much has been conducted on biogeochemical processes such as the nitrogen cycle. This study aims to determine the median lethal concentration (LC50) of the produced water that would cause mortality of 50% of the exposed population of Nitrosomonas sp. (test organism) which is involved in the ammonification step of the Nitrogen cycle.
 Study Design: For the purpose of this study, acute toxicity testing was done for 48 hours to determine the effect of the untreated and treated produced wastewater on the test organism. The LC50 is the median lethal concentration that would cause mortality of 50% of the exposed population of the test organisms.
 Methodology: Toxicity effects of treated and untreated produced wastewater were determined following standard procedures against the test organism (Nitrosomonas sp). The resultant output of the probit analysis was generated from the SPSS statistical programme.
 Results: Results showed that the mean LC50 for the untreated produced wastewater at the 48-hour test period of bioassay was 3.27mg/L, while the mean LC50 for the treated wastewater was found to be 6.69mg/L. The mean percentage mortality of Nitrosomonas sp. for the untreated produced waster water ranged from 37%(0.01mg/l) to 90%(100mg/l), while for the treated, percentage mortality ranged from 27%(0.01mg/l) to 84%(100mg/l) at the end of the 48 hour test duration.
 Conclusion: Toxicity of treated and untreated wastewater against Nitrosomonas sp increased with time and decreased considerably with treatment, corresponding to positive correlation as observed statistically between toxicants with respect to concentration and time of exposure for untreated and treated wastewater against Nitrosomonas sp. These results indicate a likey inteference of the nitrogen cycle by contamination of untreated produced water in the environment and by extension impairment of the productivity of the environment.

Development of a real-time PCR (qPCR) method for the identification of the invasive paddle crab Charybdis japonica (Crustacea, Portunidae).

Crabs can be transported beyond their native range via anthropogenic-mediated means such as aquarium trade, live seafood trade and shipping. Once introduced into new locations, they can establish persisting populations and become invasive, often leading to negative impacts on the recipient environment and native species. Molecular techniques are increasingly being used as complementary tools in biosecurity surveillance and monitoring plans for invasive species. Molecular tools can be particularly useful for early detection, rapid identification and discrimination of closely related species, including when diagnostic morphological characters are absent or challenging, such as early life stages, or when only part of the animal is available. In this study, we developed a species-specific qPCR assay, which targets the cytochrome c oxidase subunit 1 (CO1) region of the Asian paddle crab Charybdis japonica. In Australia, as well as many parts of the world, this species is considered invasive and routine biosecurity surveillance is conducted to reduce the risk of establishment. Through rigorous testing of tissue from target and non-target species we demonstrate that this assay is sensitive enough to detect as little as two copies per reaction and does not cross amplify with other closely related species. Field samples and environmental samples spiked with C. japonica DNA in high and low concentrations indicate that this assay is also a promising tool for detecting trace amounts of C. japonica eDNA in complex substrates, making it a useful complementary tool in marine biosecurity assessments.

Assessment of the Impacts of Artisanal Refinery of Crude Oil On Surface Water, Ground Water And Sediment Quality At Obi-Ayagha Community In Delta State Nigeria

<p style="text-align: justify;"><strong>Aim: </strong>This study aims to assess the impacts of artisanal refinery activities on the quality of surface water, ground water, sediment and microbial density of the recipient environment at the abandoned artisanal refinery site in Obi-Ayagha community, Ughelli South, Delta State.</p> <p style="text-align: justify;"><strong>Place and Duration of Study: </strong>Abandoned artisanal refinery hydrocarbon impacted site, Obi-Ayagha, Ughelli South, Delta State, Nigeria. During was from September 2021- February 2022.</p> <p style="text-align: justify;"><strong>Methodology: </strong><strong>F</strong>ield sampling techniques were consistent with established and standards methodologies, Environmental Guidelines and Standards for Petroleum Industries in Nigeria (EGASPIN) and Federal Ministry of Environment (FMENV) procedural guidelines. Composite surface water samples were collected using a water sampler, ground water was collected using a water pump from drilled boreholes in the study site. Sediment sample was collected using Eckman dredge (grab) from the surrounding river around the study site. Physicochemical, microbial and metal parameters were analysed in the collected samples and controls, using standard methods to assess the impact of hydrocarbon contaminant from the artisanal refinery activities on the recipient environment.</p> <p style="text-align: justify;"><strong>Results: </strong> The study revealed that there was a significant difference in Biochemical Oxygen Demand (BOD<sub>5</sub>) values for the three borehole water sampled, with a mean value of 5.23± 3.0 mg/l and the control borehole site (3.00 ± 2mg/l). Total Petroleum Hydrocarbon results were below the instrument detection limit for the surface and ground water samples, while it recorded 5.38mg/kg for the sediment sample. Polyaromatic hydrocarbon results for all samples analysed were below the instrument detection limit of <0.0001mg/kg. Total heterotrophic Bacteria counts obtained were between 2.08 -2.13 x 10<sup>3</sup> CFU/ml, 1.13 - 1.26 x 10<sup>3 </sup>CFU/ml and 2.36 x 10<sup>5 </sup>CFU/g for surface water, groundwater and sediment samples respectively. Values obtained for all metals analysed in the study samples were within regulatory stipulated limits. Iron metal, though does not have available limits for sediment samples, recorded the highest concentration of 5585 ± 2.12 mg/kg in relation to other metals.</p> <p style="text-align: justify;"><strong>Conclusion:</strong>Results obtained from the environmental samples analysed showed the parameters assessed were within regulatory limits. This could have been due to natural attenuation(remediation) of the environment giving the prolonged period of abandonment of the artisanal refining activities<strong>.</strong></p> <p style="text-align: justify;">The integration of artisanal and modular refinery operations into the oil and gas sector will curtail illegal oil activities in the Niger Delta regions and will also promote the availability of petroleum products, stabilize prices, eliminate shipping costs and provide employment opportunities for the inhabitants in the region and Nigeria in general. It is further recommended that with enough artisanal and modular refineries being granted license by the Federal Government in the country, Nigeria should be able to conserve foreign exchange currently utilized for the importation of petroleum products and promote socio-economic development.</p>

Stable Isotopes Reveal Algal Assimilation in the Carnivorous Sea Slug Pleurobranchaea maculata (Quoy & Gaimard, 1832) on Patagonian Coasts

Exotic species that achieve successful invasions often show considerable dietary plasticity in resource choice, sometimes adjusting their diet to new or variable resources. This can increase species' impact in the recipient environment. In this study, we explore the diet of the invasive gray side-gilled sea slug Pleurobranchaea maculata (Quoy & Gaimard, 1832) in two environments with contrasting presence of algae (different depths) on northern Patagonian coasts, by means of stable isotope analysis. Results showed the most probable prey contribution to the diet of shallow individuals of P. maculata to be algae, whereas colonial tunicates were the preferred prey in deep environments. Therefore, we suggest that P. maculata behaves as an omnivorous species in the receiving community, because it consumes and assimilates the algae, which represents a dietary shift compared to their original feeding habits (carnivorous). This species exhibited the ability to adapt to different dietary resources by showing significant differences in niche locations, niche breadth, and exhibiting little to no overlap between different environments, which supports the previous description of P. maculata as a generalist consumer. Pleurobranchaea maculata's dietary plasticity might drive ecological consequences in the invaded community. Thus, it is important to monitor for future changes in the benthic community to develop efficient programs for the management of this invasive voracious species.

THE ROLE OF RELATIONSHIP FACTORS IN HARMFUL CAREGIVER BEHAVIORS: OLDER CHILDREN CARING FOR PARENTS WITH DEMENTIA

Abstract Elder abuse by family caregivers is an often-overlooked phenomenon that affects many older adults. Especially, retirement-aged children caring for their oldest-old parents with dementia may be at greater risk of engaging in harmful or abusive behaviors, given their own age-related health issues and other competing caregiving demands. Most of the elder abuse literature has focused on general demographic predictors of elder abuse, regarding the caregiver, care recipient, and the care environment. Less attention has been paid towards relationship factors, which may play a large role among these parent-child dyads. This study examined how relationship factors are associated with potentially harmful caregiver behaviors (PHCB; e.g., screaming), which have been identified as “early warning signs” for elder abuse. Relationship factors of interest include positive and negative relationship quality measured by caregivers’ mean scores on the support and conflict subscales on the Quality of Relationship Inventory (QRI). We conducted in-depth interviews with 88 caregivers (65+) who are caring for their parents with dementia (90+) as the part of the Boston Aging Together Study. Regression models revealed that relationship conflict was significantly associated with higher levels of PHCB, accounting for caregiver, care recipient, and care environment characteristics. The creation of screeners to identify “high conflict” care dyads could prove useful in the early detection and intervention of potential elder abuse cases, given that caregivers may be more willing to report negative aspects of their relationship (e.g., fighting) than more obviously harmful or abusive behaviors.

A positive blood culture is associated with a lower haemoglobin increment in hospitalized patients after red blood cell transfusion.

Abundant clinical evidence supports the safety of red blood cell (RBC) concentrates for transfusion irrespective of storage age, but still, less is known about how recipient characteristics may affect post-transfusion RBC recovery and function. Septic patients are frequently transfused. We hypothesized that the recipient environment in patients with septicaemia would blunt the increase in post-transfusion blood haemoglobin (Hb). The main objective was to compare the post-transfusion Hb increment in hospitalized patients with or without a positive blood culture. A retrospective cohort study using data from the Transfusion Research, Utilization, Surveillance, and Tracking database (TRUST) was performed. All adult non-trauma in-patients transfused between 2010 and 2017 with ≥1 RBC unit, and for whom both pre- and post-transfusion complete blood count and pre-transfusion blood culture data were available were included. A general linear model with binary blood culture positivity was fit for continuous Hb increment after transfusion and was adjusted for patient demographic parameters and transfusion-related covariates. Among 210,263 admitted patients, 6252 were transfused: 596 had positive cultures, and 5656 had negative blood cultures. A modelled Hb deficit of 1.50 g/L in blood culture-positive patients was found. All covariates had a significant effect on Hb increment, except for the age of the transfused RBC. Recipient blood culture positivity was associated with a statistically significant but modestly lower post-transfusion Hb increment in hospitalized patients. In isolation, the effect is unlikely to be clinically significant, but it could become so in combination with other recipient characteristics.

Time, Mediated through Plant Versatility, Is a Better Predictor of Medicinal Status of Alien Plants

Ethnobotany has been, for too long, a descriptive discipline. However, ethnobotanists are increasingly calling for a paradigm shift towards the formulation of unifying theories and hypothesis-driven research in ethnobotany. Here, we formulated a theory, termed time-since-introduction theory, to explain the integration of alien plants into local pharmacopoeias in their recipient environment. This theory suggests that the factor time is paramount in determining which alien plants are more likely to be included in the medicinal flora of the areas they are introduced in. The theory relies on three hypotheses, the availability and versatility hypotheses alongside the residence time hypothesis newly proposed in the present study. We tested this theory by fitting a structural equation model to ethnobotanical data collected on South Africa’s alien woody flora. Although residence time is a direct predictor of the medicinal status of alien plants, it is a better predictor when mediated through plant versatility. These findings are in support of the theory, and we consequently proposed a framework that can be used to understand different paths linking all three hypotheses. Collectively, our study shows the value of time in the development of ethnobotanical knowledge and fully responds to the pressing call for a paradigm shift in ethnobotany.

Equilibrium, Kinetic and Thermodynamic Studies of Dyes in Aqueous Solution onto Iron Nanocomposite Stabilized by Irvingia gabonensis Leaf Extract

Elimination of dyes in contaminated water or wastewater has become a universal challenge because of their colouration, toxicity, mutagenicity and carcinogenicity when discharged into the recipient environment without treatment and several technologies have been developed to deal with this problem. This paper reports the potential of exploring the use and comparison of conventional iron zero-valent (nZVI) nanoparticle and Irvingia gabonensis stabilized iron nanocomposite (Ig-nZVI) for the elimination of methyl red (MR) and methyl orange (MO) dyes in aqueous solution under effect of different experimental conditions of adsorbent dosage, initial dye concentrations, pH, contact time and temperature. Data obtained show an increase in percent dye elimination as the amount of adsorbent increased. The optimal removal of MR and MO occurred in ˂ 60 min of the start of each experimentation, obtained at a maximum pH of 5.1 at 98.5% and 80.6% for adsorbent dosage of 0.3g/50 mL and 20 mg/L initial dye concentration at temperature of 27oC. The experimental data fitted the Lamgmuir isotherm with maximum adsorption capacity (qmax) of 166.7mg/g (Ig-nZVI) and 83.35 mg/g (nZVI) for MR while 128.21 mg/g (Ig-nZVI) and 40.02.5 mg/g (nZVI) were obtained for MO. Kinetics studies showed that the removal of MR and MO fitted the pseudo second-order model. The adsorption of MR and MO were endothermic and spontaneous with enthalpy values of 3.39kJ/mol (Ig-nZVI) and 776.26kJ/mol (nZVI) and standard Gibbs free energy values of -5.95kJ/mol (Ig-nZVI) and -12.00kJ/mol (nZVI). Thermodynamic studies (ΔG < 0, ΔH < 0, ΔS > 0) implied a spontaneous and exothermic process in nature. The adsorption of MO was endothermic and spontaneous with enthalpy values of 31.70kJ/mol (Ig-nZVI) and 20.91kJ/mol (nZVI) and standard Gibbs free energy values of -5.92kJ/mol and -7.07kJ/mol for Ig-nZVI and nZVI respectively. Adsorbent produced from leaf extracts of African mango tree (Irvingia gabonensis) and stabilized by iron oxide could be an attractive option for elimination of dye from industrial effluents.

3156 – BONE MARROW TRANSPLANTATION COMPROMISES THE REGENERATIVE CAPACITY OF THE NICHE

In bone marrow transplantation (BMT), the recipient environment is conditioned by myeloablative treatment. In many patients, this is associated with long-term osteoporotic changes. To assess the contributions of recipient conditioning and aging of the niche, we compared multipotent stromal and progenitor cells (MSPCs) from young (young: 3 mo old), middle-aged mice (aged: 13 mo old) with mice 10 months after BMT (BMT; total age of 13 mo). Our experiments show reduced numbers of (CD45/Ter119)- CD31- CD166low/med SCA1+ MSPCs with a strongly reduced CFU-F frequency, suggesting a functional compromise of MSPC in BMT. On the cellular level, BMT MSPCs show an increased ROS production compared to aged and young mice. In addition, BMT MSPC show disorganized F-actin stress fibers with increased activation of the small GTPase CDC42 compared to both young and aged MSPCs. In experiments with patient-derived human BMT MSPC, we found similar deregulation of F-Actin, compared to MSPC from young and aged healthy donors (HD). To prevent damaging functional and cytoskeletal changes after conditioning, we treated a small cohort of control and BMT mice with CASIN, an inhibitor of CDC42, in the first week after transplantation. This resulted in a 1.2-fold higher engraftment without affecting early regeneration. Interestingly, CASIN-treated male BMT mice also show elevated trabecular separation and thickness with a slightly higher bone volume compared to treated controls. Our results show that early CASIN-treatment after BMT increases osteogenesis and reduces osteoporotic changes commonly noted in human patients after BMT. Our findings could help in devising strategies to improve long-term restoration of tissues after transplantation, particularly in aging graft recipients. In bone marrow transplantation (BMT), the recipient environment is conditioned by myeloablative treatment. In many patients, this is associated with long-term osteoporotic changes. To assess the contributions of recipient conditioning and aging of the niche, we compared multipotent stromal and progenitor cells (MSPCs) from young (young: 3 mo old), middle-aged mice (aged: 13 mo old) with mice 10 months after BMT (BMT; total age of 13 mo). Our experiments show reduced numbers of (CD45/Ter119)- CD31- CD166low/med SCA1+ MSPCs with a strongly reduced CFU-F frequency, suggesting a functional compromise of MSPC in BMT. On the cellular level, BMT MSPCs show an increased ROS production compared to aged and young mice. In addition, BMT MSPC show disorganized F-actin stress fibers with increased activation of the small GTPase CDC42 compared to both young and aged MSPCs. In experiments with patient-derived human BMT MSPC, we found similar deregulation of F-Actin, compared to MSPC from young and aged healthy donors (HD). To prevent damaging functional and cytoskeletal changes after conditioning, we treated a small cohort of control and BMT mice with CASIN, an inhibitor of CDC42, in the first week after transplantation. This resulted in a 1.2-fold higher engraftment without affecting early regeneration. Interestingly, CASIN-treated male BMT mice also show elevated trabecular separation and thickness with a slightly higher bone volume compared to treated controls. Our results show that early CASIN-treatment after BMT increases osteogenesis and reduces osteoporotic changes commonly noted in human patients after BMT. Our findings could help in devising strategies to improve long-term restoration of tissues after transplantation, particularly in aging graft recipients.

More than chores: The invisible health work of family caregivers in rural New Brunswick, Canada.

Most home care for people living with chronic illness or disability is provided by informal, or unpaid, family members. Family caregivers in rural New Brunswick engage in essential work to maintain the home as a site of care. Renovations, property maintenance, and the administrative work involved in accessing medical equipment and managing staff are examples of the types of invisible labour involved in interacting with a complex care environment. Conversations with 13 family caregivers across a small rural Canadian province suggest that even when resources are 'available', place-based factors involved in caring at home in a rural setting make it difficult for carers to use these resources and accessing them becomes another form of work itself. Similar to Wiles et al.'s (2018) findings in their study of end-of-life family care in Aotearoa, New Zealand, carers in rural New Brunswick spoke of their activities as part of an ongoing process of interaction with the care recipient and care environment. Carers with fewer financial and material resources experienced higher burdens of invisible work. The paper sheds light on the types of labour involved in 'knowing, doing, and negotiating' care at home and re-categorizes these activities as 'health work' as a means of informing home care policy. The paper finds that family caregivers are aware of their invisible work, characterize it as essential health work, and seek recognition for their complex contribution to the formal health system.

Nesting innovations allow population growth in an invasive population of rose-ringed parakeets.

Certain traits of recipient environments, such as the availability of limiting resources, strongly determine the establishment success and spread of non-native species. These limitations may be overcome through behavioral plasticity, allowing them to exploit alternative resources. Here, we show how a secondary cavity nester bird, the rose-ringed parakeet Psittacula krameri, innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife (Canary Islands). We observed that some breeding pairs excavated their own nest cavities in palms, thus becoming primary cavity nester, whereas others occupied nests built with wood sticks by another invasive species, the monk parakeet Myiopsitta monachus. The use of these novel nesting strategies increased the number of breeding pairs by up to 52% over 6 years, contributing to a 128.8% increase of the whole population. Innovative nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural cavities. Occupation of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest predators. Our results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment, thus facilitating its population growth and invasion process. Potential behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked, and should be considered for effective management plans.

The Post-Storage Performance of RBCs from Beta-Thalassemia Trait Donors Is Related to Their Storability Profile.

Blood donors with beta-thalassemia traits (βThal+) have proven to be good “storers”, since their stored RBCs are resistant to lysis and resilient against oxidative/proteotoxic stress. To examine the performance of these RBCs post-storage, stored βThal+ and control RBCs were reconstituted in plasma donated from transfusion-dependent beta-thalassemic patients and healthy controls, and incubated for 24 h at body temperature. Several physiological parameters, including hemolysis, were evaluated. Moreover, labeled fresh/stored RBCs from the two groups were transfused in mice to assess 24 h recovery. All hemolysis metrics were better in the group of heterozygotes and distinguished them against controls in the plasma environment. The reconstituted βThal+ samples also presented higher proteasome activity and fewer procoagulant extracellular vesicles. Transfusion to mice demonstrated that βThal+ RBCs present a marginal trend for higher recovery, regardless of the recipient’s immune background and the RBC storage age. According to correlation analysis, several of these advantageous post-storage characteristics are related to storage phenotypes, like the cytoskeleton composition, low cellular fragility, and enhanced membrane proteostasis that characterize stored βThal+ RBCs. Overall, it seems that the intrinsic physiology of βThal+ RBCs benefits them in conditions mimicking a recipient environment, and in the circulation of animal models; findings that warrant validation in clinical trials.

Megakaryocyte progenitor cell function is enhanced upon aging despite the functional decline of aged hematopoietic stem cells.

SummaryAge-related morbidity is associated with a decline in hematopoietic stem cell (HSC) function, but the mechanisms of HSC aging remain unclear. We performed heterochronic HSC transplants followed by quantitative analysis of cell reconstitution. Although young HSCs outperformed old HSCs in young recipients, young HSCs unexpectedly failed to outcompete the old HSCs of aged recipients. Interestingly, despite substantial enrichment of megakaryocyte progenitors (MkPs) in old mice in situ and reported platelet (Plt) priming with age, transplanted old HSCs were deficient in reconstitution of all lineages, including MkPs and Plts. We therefore performed functional analysis of young and old MkPs. Surprisingly, old MkPs displayed unmistakably greater regenerative capacity compared with young MkPs. Transcriptome analysis revealed putative molecular regulators of old MkP expansion. Collectively, these data demonstrated that aging affects HSCs and megakaryopoiesis in fundamentally different ways: whereas old HSCs functionally decline, MkPs gain expansion capacity upon aging.

Acute toxicity assessment of produced water effluent stream on selected local organisms in Delta state, Nigeria.

This study evaluated toxicity level of produced water effluent on indigenous organisms in Delta state, Nigeria. Four test organisms, Vibrio fischeri, Palaemonetes africanus, Tympanosomas fuscatus, and Tilapia guineensis, were selected for toxicity assessment using effluent streams from treated produced water and water from the produced water recipient environment. Representative samples of treated produced water effluent were collected from the bulk header within the oil terminal and within the discharge environment. Acute toxicity tests were carried out using the Microtox® Model 500. The results of the acute toxicity tests on V. fischeri revealed that the average inhibitive concentration (IC50) for treated produced water at 5 min and 15 min was 22.20% and 31.17% and the no effect concentration (NOEC) and low effect concentration (LOEC) at 5 min and 15 min was 5.63% and 5.63%, respectively. In the recipient water, at 5 min and 15 min, IC50 estimate was of 33.57% and 47.02% while the NOEC and LOEC were 5.63% and 5.63%, respectively. The average IC50, NOEC, LOEC, toxicity unit-acute (TUa), toxicity unit-chronic (TUc), and toxicity factor (TF) toxicity values for P. africanus were 80.606%, 66.990%, and 73.13%; 1.24, 1.49, and 2066.82; 42.24%, 6.165%, and 11.936%; 2.37, 16.21, and 25.54 in treated and recipient water, respectively. In T. guineensis, average IC50, LOEC, NOEC, TUa, TUc, and TF were 4.86%, 1.786%, 1.059%, 20.60, 94.34, and 269.72 and 5.090%, 1.828%, 1.070%, 19.65, 93.46, and 282.78 for treated produced water and recipient environment, respectively. There was no mortality in T. fuscatus var radula exposed to both treated produced water and recipient water.

Photopolymerizable Hydrogel-Encapsulated Fibromodulin-Reprogrammed Cells for Muscle Regeneration.

A central challenge in tissue engineering is obtaining a suitable cell type with a capable delivery vehicle to replace or repair damaged or diseased tissues with tissue mimics. Notably, for skeletal muscle tissue engineering, given the inadequate availability and regenerative capability of endogenous myogenic progenitor cells as well as the tumorigenic risks presented by the currently available pluri- and multipotent stem cells, seeking a safe regenerative cell source is urgently demanded. To conquer this problem, we previously established a novel reprogramming technology that can generate multipotent cells from dermal fibroblasts using a single protein, fibromodulin (FMOD). The yield FMOD-reprogrammed (FReP) cells exhibit exceeding myogenic capability without tumorigenic risk, making them a promising and safe cell source for skeletal muscle establishment. In addition to using the optimal cell for implantation, it is equally essential to maintain cellular localization and retention in the recipient tissue environment for critical-sized muscle tissue establishment. In this study, we demonstrate that the photopolymerizable methacrylated glycol chitosan (MeGC)/type I collagen (ColI)-hydrogel provides a desirable microenvironment for encapsulated FReP cell survival, spreading, extension, and formation of myotubes in the hydrogel three-dimensionally in vitro, without undesired osteogenic, chondrogenic, or tenogenic differentiation. Furthermore, gene profiling revealed a paired box 7 (PAX7) → myogenic factor 5 (MYF5) → myogenic determination 1 (MYOD1) → myogenin (MYOG) → myosin cassette elevation in the encapsulated FReP cells during myogenic differentiation, which is similar to that of the predominant driver of endogenous skeletal muscle regeneration, satellite cells. These findings constitute the evidence that the FReP cell-MeGC/ColI-hydrogel construct is a promising tissue engineering mimic for skeletal muscle generation in vitro, and thus possesses the extraordinary potential for further in vivo validation.