The ectomycorrhizal fungus Paxillus ammoniavirescens influences the effects of salinity on loblolly pine in response to potassium availability.

Salinity is an increasing problem in coastal areas affected by saltwater intrusion, with deleterious effects on tree health and forest growth. Ectomycorrhizal (ECM) fungi may improve the salinity tolerance of host trees, but the impact of external potassium (K+ ) availability on these effects is still unclear. Here, we performed several experiments with the ECM fungus Paxillus ammoniavirescens and loblolly pine (Pinus taeda L.) in axenic and symbiotic conditions at limited or sufficient K+ and increasing sodium (Na+ ) concentrations. Growth rate, biomass, nutrient content, and K+ transporter expression levels were recorded for the fungus, and the colonization rate, root development parameters, biomass, and shoot nutrient accumulation were determined for mycorrhizal and non-mycorrhizal plants. P. ammoniavirescens was tolerant to high salinity, although growth and nutrient concentrations varied with K+ availability and increasing Na+ exposure. While loblolly pine root growth and development decreased with increasing salinity, ECM colonization was unaffected by pine response to salinity. The mycorrhizal influence on loblolly pine salinity response was strongly dependent on external K+ availability. This study reveals that P. ammoniavirescens can reduce Na+ accumulation of salt-exposed loblolly pine, but this effect depends on external K+ availability.

Radical Scavenging, Hemocompatibility, and Antibacterial Activity against MDR Acinetobacter baumannii in Alginate-Based Aerogels Containing Lipoic Acid-Capped Silver Nanoparticles.

Retaining the hemocompatibility, supporting cell growth, and exhibiting anti-inflammatory and antioxidant properties, while having antimicrobial activity, particularly against multidrug-resistant bacteria (MDR), remain a challenge when designing aerogels for biomedical applications. Here, we report that our synthesized alginate-based aerogels containing either 7.5 or 11.25 µg of lipoic acid-capped silver nanoparticles (AgNPs) showed improved hemocompatibility properties while retaining their antimicrobial effect against MDR Acinetobacter baumannii and the reference strain Escherichia coli, relative to a commercial dressing and polymyxin B, used as a reference. The differences in terms of the microstructure and nature of the silver, used as the bioactive agent, between our synthesized aerogels and the commercial dressing used as a reference allowed us to improve several biological properties in our aerogels with respect to the reference commercial material. Our aerogels showed significantly higher antioxidant capacity, in terms of nmol of Trolox equivalent antioxidant capacity per mg of aerogel, than the commercial dressing. All our synthesized aerogels showed anti-inflammatory activity, expressed as nmol of indomethacin equivalent anti-inflammatory activity per mg of aerogel, while this property was not found in the commercial dressing material. Finally, our aerogels were highly hemocompatible (less than 1% hemolysis ratio); however, the commercial material showed a 20% hemolysis rate. Therefore, our alginate-based aerogels with lipoic acid-capped AgNPs hold promise for biomedical applications.

Substance use typologies among young people experiencing homelessness in seven cities across the United States: A latent class analysis.

BACKGROUND: Substance use and other health-risk risk factors, including mental health, trauma, and sexual-risk behaviors, often co-occur among youth experiencing homelessness (YEH). The present study aimed to identify subgroups of YEH based on polysubstance use and the linkages to sociodemographic and health-risk characteristics. METHODS: From June 2016 to July 2017, 1,426 YEH (aged 18-26 years) were recruited from seven cities (Houston, Los Angeles, Denver, Phoenix, New York City, St. Louis, San Jose). Participants provided information via a self-administered electronic survey on substance use, mental health, trauma, sexual risk behaviors, and sociodemographic characteristics. The majority of YEH identified as Black (37.3%), cisgender (92.8%), and heterosexual (69.2%). On average, YEH were 20.9 years (SD = 2.1). This study employed latent class analysis (LCA) to identify subgroups of YEH according to their substance use. Multinomial logistic regression analyses were conducted to identify sociodemographic and health-risk characteristics associated with class-membership. RESULTS: Four latent classes of YEH substance use were identified: (1) high polysubstance use; (2) moderate stimulant and high marijuana, alcohol, and prescription drug use; (3) high marijuana, alcohol, and prescription drug use; (4) low/moderate marijuana and alcohol use. Multinomial logistic regression models indicated that geographic location, gender, race/ethnicity, mental health, trauma history, and sexual risk behaviors were significant correlates of substance use class membership among YEH. CONCLUSIONS: These findings offer important implications for the prevention and treatment of substance use among YEH. Screening protocols should consider co-occurring risk factors such as traumatic experiences, sexual risk behaviors, and mental health history as indicators of polysubstance use.

Agrobacterium tumefaciens-mediated transformation of Nigrospora sp. isolated from switchgrass leaves and antagonistic toward plant pathogens.

Nigrospora is a diverse genus of fungi colonizing plants through endophytic, pathogenic, or saprobic interactions. Endophytic isolates can improve growth and development of host plants, as well as their resistance to microbial pathogens, but exactly how they do so remains poorly understood. Developing a reliable transformation method is crucial to investigate these mechanisms, in particular to identify pivotal genes for specific functions that correlate with specific traits. In this study, we identified eight isolates of Nigrospora sp. internally colonizing the leaves of switchgrass plants cultivated in North Carolina. Using an Agrobacterium tumefaciens-mediated transformation approach with control and GFP-expressing vectors, we report the first successful transformation of two Nigrospora isolates. Finally, we demonstrate that wild-type and transgenic isolates both negatively impact the growth of two plant pathogens in co-culture conditions, Bipolaris maydis and Parastagonospora nodorum, responsible for the Southern Leaf Blight and Septoria Nodorum Blotch diseases, respectively. The GFP-transformed strains developed here can therefore serve as accurate reporters of spatial interactions in future studies of Nigrospora and pathogens in the plant. Finally, the transformation method we describe lays the foundation for further genetic research on the Nigrospora genus to expand our mechanistic understanding of plant-endophyte interactions.

Overexpression of the HcPT1.1 transporter in Hebeloma cylindrosporum alters the phosphorus accumulation of Pinus pinaster and the distribution of HcPT2 in ectomycorrhizae.

Ectomycorrhizal (ECM) fungi are associated with the roots of woody plants in temperate and boreal forests and help them to acquire water and nutrients, particularly phosphorus (P). However, the molecular mechanisms responsible for the transfer of P from the fungus to the plant in ectomycorrhizae are still poorly understood. In the model association between the ECM fungus Hebeloma cylindrosporum and its host plant Pinus pinaster, we have shown that the fungus, which possesses three H+:Pi symporters (HcPT1.1, HcPT1.2 and HcPT2), expresses mainly HcPT1.1 and HcPT2 in the extraradical and intraradical hyphae of ectomycorrhizae to transport P from the soil to colonized roots. The present study focuses on the role of the HcPT1.1 protein in plant P nutrition, in function of P availability. We artificially overexpressed this P transporter by fungal Agrotransformation and investigated the effect of the different lines, wild-type and transformed ones, on plant P accumulation, the distribution of HcPT1.1 and HcPT2 proteins in ectomycorrhizae by immunolocalization, and 32P efflux in an experimental system mimicking intraradical hyphae. Surprisingly, we showed that plants interacting with transgenic fungal lines overexpressing HcPT1.1 did not accumulate more P in their shoots than plants colonized with the control ones. Although the overexpression of HcPT1.1 did not affect the expression levels of the other two P transporters in pure cultures, it induced a strong reduction in HcPT2 proteins in ectomycorrhizae, particularly in intraradical hyphae, but still improved the P status of host plant shoots compared with non-mycorrhizal plants. Finally, 32P efflux from hyphae was higher in lines overexpressing HcPT1.1 than in the control ones. These results suggest that a tight regulation and/or a functional redundancy between the H+:Pi symporters of H. cylindrosporum might exist to ensure a sustainable P delivery to P. pinaster roots.

Isolation and Identification of Mesenchymal Stem Cells Derived from Adipose Tissue of Sprague Dawley Rats.

Adult mesenchymal cells have revolutionized molecular and cell biology in recent decades. They can differentiate into different specialized cell types, in addition to their great capacity for self-renewal, migration, and proliferation. Adipose tissue is one of the least invasive and most accessible sources of mesenchymal cells. It has also been reported to have higher yields compared to other sources, as well as superior immunomodulatory properties. Recently, different procedures for obtaining adult mesenchymal cells from different tissue sources and animal species have been published. After evaluating the criteria of some authors, we standardized a methodology applicable to different purposes and easily reproducible. A pool of stromal vascular fraction (SVF) from perirenal and epididymal adipose tissue allowed us to develop primary cultures with optimal morphology and functionality. The cells were observed adhered to the plastic surface for 24 h, and exhibited a fibroblast-like morphology, with prolongations and a tendency to form colonies. Flow cytometry (FC) and immunofluorescence (IF) techniques were used to assess the expression of the membrane markers CD105, CD9, CD63, CD31, and CD34. The ability of adipose-derived stem cells (ASCs) to differentiate into the adipogenic lineage was also assessed using a cocktail of factors (4 µM insulin, 0.5 mM 3-methyl-iso-butyl-xanthine, and 1 µM dexamethasone). After 48 h, a gradual loss of fibroblastoid morphology was observed, and at 12 days, the presence of lipid droplets positive to oil red staining was confirmed. In summary, a procedure is proposed to obtain optimal and functional ASC cultures for application in regenerative medicine.

Development of split-root assays for loblolly pine (Pinus taeda L.) seedlings to study ectomycorrhizal symbioses.

Split-root techniques are valuable to investigate systemic vs. local plant responses to biotic and abiotic environmental factors, including interactions with soil microbes. Loblolly pine (Pinus taeda L.) is an economically important tree species that associates with many ectomycorrhizal fungi. However, a protocol for the establishment of split-roots experiments with loblolly pine has not been described so far. This method successfully establishes a split-root system in eight weeks following germination of loblolly pine seedlings. Rapid lateral root elongation is promoted by cutting the primary root tip and growing the seedlings in a hydroponic medium. Lateral roots can then be divided into two separated compartments and inoculated with ectomycorrhizal fungi. The method was validated by growth of split roots with or without inoculation. Root dry biomass was not significantly different between separated non-inoculated roots. Ectomycorrhizal colonization was not detected on the non-inoculated side of roots that were inoculated only on one side, demonstrating the success of the technique as a valuable method for split-root experiments in P. taeda. In addition to ectomycorrhizal fungi, researchers can use this method with loblolly pine to study systemic and local responses to a variety of other biotic or abiotic factors in the root environment.•We describe a protocol to produce split-roots in loblolly pine (Pinus taeda L.) in eight weeks.•This protocol uses hydroponics to promote the elongation of loblolly pine roots.•We validated this protocol by determining split-root biomass and inoculating the seedlings with the ectomycorrhizal fungi Paxillus ammoniavirescens or Hebeloma cylindrosporum.

The putative transporter MtUMAMIT14 participates in nodule formation in Medicago truncatula.

Transport systems are crucial in many plant processes, including plant-microbe interactions. Nodule formation and function in legumes involve the expression and regulation of multiple transport proteins, and many are still uncharacterized, particularly for nitrogen transport. Amino acids originating from the nitrogen-fixing process are an essential form of nitrogen for legumes. This work evaluates the role of MtN21 (henceforth MtUMAMIT14), a putative transport system from the MtN21/EamA-like/UMAMIT family, in nodule formation and nitrogen fixation in Medicago truncatula. To dissect this transporter's role, we assessed the expression of MtUMAMIT14 using GUS staining, localized the corresponding protein in M. truncatula root and tobacco leaf cells, and investigated two independent MtUMAMIT14 mutant lines. Our results indicate that MtUMAMIT14 is localized in endosomal structures and is expressed in both the infection zone and interzone of nodules. Comparison of mutant and wild-type M. truncatula indicates MtUMAMIT14, the expression of which is dependent on the presence of NIN, DNF1, and DNF2, plays a role in nodule formation and nitrogen-fixation. While the function of the transporter is still unclear, our results connect root nodule nitrogen fixation in legumes with the UMAMIT family.

Secrets of the fungus-specific potassium channel TOK family.

Several families of potassium (K+) channels are found in membranes of all eukaryotes, underlining the importance of K+ uptake and redistribution within and between cells and organs. Among them, TOK (tandem-pore outward-rectifying K+) channels consist of eight transmembrane domains and two pore domains per subunit organized in dimers. These channels were originally studied in yeast, but recent identifications and characterizations in filamentous fungi shed new light on this fungus-specific K+ channel family. Although their actual function in vivo is often puzzling, recent works indicate a role in cellular K+ homeostasis and even suggest a role in plant-fungus symbioses. This review aims at synthesizing the current knowledge on fungal TOK channels and discussing their potential role in yeasts and filamentous fungi.

Lipoma cardiaco / Cardiac masses

Resumen Las masas cardiacas son entidades raras que cursan con un espectro muy variado de manifestaciones clínicas que van desde cuadros asintomáticos hasta compromiso hemodinámico severo. Entre las lesiones benignas, los lipomas cardiacos son los segundos en frecuencia. Corresponden principalmente a lesiones neoplásicas benignas; no obstante, se pueden presentar otras patologías como trombos, vegetaciones y variantes de la normalidad. Gracias a la disponibilidad de técnicas de imagen de alta definición, como la ecocardiografía, la TC y la RM, ha aumentado su detección y tratamiento temprano. En el ámbito terapéutico se ofrece manejo quirúrgico, pues las imágenes no permiten la caracterización y diferenciación fidedigna de la naturaleza de las masas cardiacas. Se describe el caso de una paciente sin antecedentes cardiovasculares, con historial de disnea crónica, en quien se identificó, a través de estudios imagenológicos, masa cardiaca adosada al ventrículo con deformación leve de cavidades derechas. Fue llevada a resección quirúrgica y por histopatología se confirmó lipoma. Este hallazgo es el más infrecuente de todos los tumores cardíacos benignos. Se resalta la importancia del conocimiento de esta enfermedad para dar tratamiento eficaz y oportuno en aras de evitar complicaciones que impacten en morbimortalidad.

Abstract Cardiac masses are rare entities that present with a very varied spectrum of clinical manifestations that go from asymptomatic to pictures with severe hemodynamic compromise, within these, cardiac lipomas are the second in frequency within benign lesions. They mainly correspond to benign neoplastic lesions, however, other pathologies such as thrombi, vegetations and variants of normality can occur. Thanks to the availability of high-definition imaging techniques, echocardiography, CT and MRI have increased early detection and treatment. In the therapeutic field, surgical management is offered, since the images do not allow the characterization and reliable differentiation of the nature of cardia masses. It is described the case of a patient with no cardiovascular history, with chronic dyspnea, in whom the presence of CM attached to the ventricle with slight deformation of the right cavities is identified by imaging studies. Was taken to surgical resection confirming the presence of lipoma by histopathology, being this finding the rarest of all benign cardiac tumors. We highlight the importance of knowing this pathology to provide effective and timely treatment to avoid complications that impact morbidity and mortality.

Engineering an incubation environment that mimics in situ conditions for in vitro coastal microbiome studies.

Coastal environments are dynamic and can vary widely on short- or long-term scales depending on location and weather. Incubation equipment that reflects these changes through programmable gradient light and temperature cycles would permit more precise in vitro coastal microbiome studies. Here we present an open-source incubation environment that mimics in situ conditions for in vitro coastal microbiome studies using a modified shaking water bath that has fully customizable temperature and light gradients that can also mimic real-time field conditions. We compared coastal microbial community profiles incubated in situ and in our build mimicking field conditions over 48 h. Analyses of congruence indicated significant overlap (p > 0.2) between microbial communities incubated in situ and in vitro at each time point.

Cesium could be used as a proxy for potassium in mycorrhizal Medicago truncatula.

Arbuscular mycorrhizal (AM) fungi interact with the roots of most land plants and help them to acquire various mineral resources from the soil, including potassium (K+). However, tracking K+ movement in AM symbiosis remains challenging. Recently, we reported that rubidium can be used as a proxy for K+ in mycorrhizal Medicago truncatula. In the present work, we investigated the possibility of using cesium (Cs+) as another proxy for K+ in AM symbiosis. Plants were placed in growing systems that include a separate compartment only accessible to the AM fungus Rhizophagus irregularis isolate 09 and in which various amounts of cesium chloride (0 mM, 0.5 mM, 1.5 mM, or 3.75 mM) were supplied. Plants were watered with sufficient K+ or K+-free nutrient solutions, and shoot and root biomass, fungal colonization, and K+ and Cs+ concentrations were recorded seven weeks after inoculation. Our results indicate that Cs+ accumulated in plant tissues only when K+ was present in the nutrient solution and when the highest concentration of Cs+ was used in the fungal compartment. Consequently, we conclude that Cs+ could be used as a proxy for K+ in AM symbiosis, but with serious limitations.

A Rare Case of Meningitis Caused by Alcaligenes faecalis in an Immunocompetent Patient.

Alcaligenes faecalis (A. faecalis) is a Gram-negative rod rarely isolated as an infective bacterium worldwide. The first cases of infections caused by this microorganism, such as pneumonia, soft tissue infections, urinary tract infections, bacteremia, and meningitis, date back more than 40 years and are almost entirely in newborns and immunosuppressed hosts. Optimal antibiotic therapy for A. faecalis has not been well established in the literature. We report a case of an immunocompetent patient in Colombia who had meningitis due to A. faecalis after a dental procedure. It is important to know about this microorganism that nowadays could be considered a potentially emerging pathogen in immunocompetent adults.

Mycorrhiza-mediated potassium transport in Medicago truncatula can be evaluated by using rubidium as a proxy.

Arbuscular mycorrhizal (AM) fungi considerably improve plant nutrient acquisition, particularly phosphorus and nitrogen. Despite the physiological importance of potassium (K+) in plants, there is increasing interest in the mycorrhizal contribution to plant K+ nutrition. Yet, methods to track K+ transport are often costly and limiting evaluation opportunities. Rubidium (Rb+) is known to be transported through same pathways as K+. As such our research efforts attempt to evaluate if Rb+ could serve as a viable proxy for evaluating K+ transport in AM symbiosis. Therefore, we examined the transport of K+ in Medicago truncatula colonized by the AM fungus Rhizophagus irregularis isolate 09 having access to various concentrations of Rb+ in custom-made two-compartment systems. Plant biomass, fungal root colonization, and shoot nutrient concentrations were recorded under sufficient and limited K+ regimes. We report that AM plants displayed higher shoot Rb+ and K+ concentrations and a greater K+:Na+ ratio relative to non-colonized plants in both sufficient and limited K+ conditions. Consequently, our results indicate that Rb+ can be used as a proxy to assess the movement of K+ in AM symbiosis, and suggest the existence of a mycorrhizal uptake pathway for K+ nutrition in M. truncatula.

Multimodality cardiac imaging in the diagnostic approach to chronic dyspnea: a patient with pericardial lipoma.

Cardiac masses are rare entities that present with a very varied spectrum of manifestations ranging from asymptomatic to severe hemodynamic compromise. They mainly correspond to benign neoplastic lesions; however, other pathologies may occur. The availability of high-definition imaging techniques has increased early detection. Nevertheless, these techniques do not allow the characterization and reliable differentiation of the nature of the mass. We describe a patient with no cardiovascular history with a chronic dyspnea, in whom the presence of a cardiac mass attached to the ventricle with slight deformation of the right cavities was identified by imaging studies. The patient underwent surgical resection, which confirmed the presence of lipoma by histopathology. This finding is the rarest of all benign cardiac tumors.

Cardiac lipomas are rare benign tumors of the heart. They are usually asymptomatic, but when symptoms occur, they are usually nonspecific, so it is necessary to consult an internist, cardiologist or pulmonologist for proper study, identification and treatment. Multimodal images are very useful in these cases.

Physiological and transcriptomic response of Medicago truncatula to colonization by high- or low-benefit arbuscular mycorrhizal fungi.

Arbuscular mycorrhizal (AM) fungi form a root endosymbiosis with many agronomically important crop species. They enhance the ability of their host to obtain nutrients from the soil and increase the tolerance to biotic and abiotic stressors. However, AM fungal species can differ in the benefits they provide to their host plants. Here, we examined the putative molecular mechanisms involved in the regulation of the physiological response of Medicago truncatula to colonization by Rhizophagus irregularis or Glomus aggregatum, which have previously been characterized as high- and low-benefit AM fungal species, respectively. Colonization with R. irregularis led to greater growth and nutrient uptake than colonization with G. aggregatum. These benefits were linked to an elevated expression in the roots of strigolactone biosynthesis genes (NSP1, NSP2, CCD7, and MAX1a), mycorrhiza-induced phosphate (PT8), ammonium (AMT2;3), and nitrate (NPF4.12) transporters and the putative ammonium transporter NIP1;5. R. irregularis also stimulated the expression of photosynthesis-related genes in the shoot and the upregulation of the sugar transporters SWEET1.2, SWEET3.3, and SWEET 12 and the lipid biosynthesis gene RAM2 in the roots. In contrast, G. aggregatum induced the expression of biotic stress defense response genes in the shoots, and several genes associated with abiotic stress in the roots. This suggests that either the host perceives colonization by G. aggregatum as pathogen attack or that G. aggregatum can prime host defense responses. Our findings highlight molecular mechanisms that host plants may use to regulate their association with high- and low-benefit arbuscular mycorrhizal symbionts.

In-Situ Bromination Enables Formal Cross-Electrophile Coupling of Alcohols with Aryl and Alkenyl Halides.

Although alcohols are one of the largest pools of alkyl substrates, approaches to utilize them in cross-coupling and cross-electrophile coupling are limited. We report the use of 1° and 2° alcohols in cross-electrophile coupling with aryl and vinyl halides to form C(sp3)-C(sp2) bonds in a one-pot strategy utilizing a very fast (<1 min) bromination. The reaction's simple benchtop setup and broad scope (42 examples, 56% ± 15% ave yield) facilitates use at all scales. The potential in parallel synthesis applications was demonstrated by successfully coupling all combinations of 8 alcohols with 12 aryl cores in a 96-well plate.

Correlation between the analysis of the dentoalveolar square and the photometric clinical diagnosis of smile.

AIM: Increased vertical growth of the maxilla is a condition that affects a large part of the population. The condition reveals a skeletal alteration of the cranio-masticatory system. One of the effects generated by the excessive vertical growth of the maxilla is a gingival smile pattern that can affect esthetic patterns as well as alter the masticatory biomechanics, which is a primary etiologic factor in temporomandibular dysfunction (TMD). Contemporary imaging aids help to optimize diagnostic analysis; perform treatment; and make an evaluation before, during, and after treatment. The present study aims to compare the clinical diagnosis of gingival smile with the dimensions of the dentoalveolar square, digitally calculated in the panoramic projection of the CBCT. MATERIALS AND METHODS: In a sample of 37 patients, an analysis was performed of the correlation between the dimensions of the dentoalveolar square of the Tatis panoramic cephalometry and the clinical photometry, applying the Tjan gingival smile analysis. RESULTS: The results show that there is high correlation and agreement between the cephalometric measurement method of the dentoalveolar square and Tjan's photometric measurement method. Both methods can be used to classify the smile type as high, medium or low. CONCLUSIONS: Analysis of the dentoalveolar square of the panoramic cephalometry provides an accurate diagnosis of the anterior vertical dimension of the maxilla as it relates to the clinical diagnosis of smile.

Split down the middle: studying arbuscular mycorrhizal and ectomycorrhizal symbioses using split-root assays.

Most land plants symbiotically interact with soil-borne fungi to ensure nutrient acquisition and tolerance to various environmental stressors. Among these symbioses, arbuscular mycorrhizal and ectomycorrhizal associations can be found in a large proportion of plants, including many crops. Split-root assays are widely used in plant research to study local and systemic signaling responses triggered by local treatments, including nutrient availability, interaction with soil microbes, or abiotic stresses. However, split-root approaches have only been occasionally used to tackle these questions with regard to mycorrhizal symbioses. This review compiles and discusses split-root assays developed to study arbuscular mycorrhizal and ectomycorrhizal symbioses, with a particular emphasis on colonization by multiple beneficial symbionts, systemic resistance induced by mycorrhizal fungi, water and nutrient transport from fungi to colonized plants, and host photosynthate allocation from the host to fungal symbionts. In addition, we highlight how the use of split-root assays could result in a better understanding of mycorrhizal symbioses, particularly for a broader range of essential nutrients, and for multipartite interactions.