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Mycorrhizal symbioses (mycorrhizas) of Ericaceae, including ericoid mycorrhiza (ErM), have been mainly studied in the Northern Hemisphere, although the highest diversity of ericaceous plants is located in the Southern Hemisphere, where several regions remain largely unexplored. One of them is South America, which harbors a remarkably high diversity of Ericaceae (691 species and 33 genera) in a wide range of environmental conditions, and a specific mycorrhizal type called cavendishioid. In this review, we compile all available information on mycorrhizas of Ericaceae in South America. We report data on the mycorrhizal type and fungal diversity in 17 and 11 ericaceous genera, respectively. We show that South American Ericaceae exhibit a high diversity of habitats and life forms and that some species from typical ErM subfamilies may also host arbuscular mycorrhiza. Also, a possible geographical pattern in South American ErM fungal communities is suggested, with Sebacinales being the dominant mycorrhizal partners of the Andean clade species from tropical mountains, while archetypal ErM fungi are common partners in southern South America species. The gathered information challenges some common assumptions about ErM and suggests that focusing on understudied regions would improve our understanding of the evolution of mycorrhizal associations in this intriguing family.

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BACKGROUND/OBJECTIVES: To assess the methodological quality of Clinical Practice Guidelines (CPG) for the diagnosis and management of Retinal Vein Occlusion (RVO). METHODS: A systematic review of CPGs for the diagnosis and management of RVO was carried out with a search in databases, metasearch engines, CPG development institutions, ophthalmology associations and CPG repositories until April 2022. Search update was performed on April 2023, with no new record available. Five CPGs published in the last 10 years in English/Spanish were selected, and 5 authors evaluated them independently, using the Appraisal of Guidelines for Research and Evaluation (AGREE-II) instrument. An individual assessment of each CPG by domain (AGREE-II), an overall assessment of the guide, and its use with or without modifications were performed. Additionally, a meta-synthesis of the recommendations for the most relevant outcomes was carried out. RESULTS: The lowest score (mean 18.8%) was for domain 5 'applicability', and the highest score (mean 62%) was for domain 4 'clarity of presentation'. The 2019 American guideline (PPP) presented the best score (40.4%) in domain 3 'rigour of development'. When evaluating the overall quality of the CPGs analysed, all CPGs could be recommended with modifications. In the meta-synthesis, anti-VEGF therapy is the first-choice therapy for macular oedema associated with RVO, but there is no clear recommendation about the type of anti-VEGF therapy to choose. Recommendations for diagnosis and follow-up are similar among the CPGs appraised. CONCLUSION: Most CPGs for the diagnosis and management of RVO have a low methodological quality assessed according to the AGREE-II. PPP has the higher score in the domain 'rigour of development'. Among the CPGs appraised, there is no clear recommendation on the type of anti-VEGF therapy to choose.

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The immunofluorescence technique has been used to identify pluripotent markers in the human amniotic epithelial cells (hAEC). hAEC belonging to human fetal membranes, specificamently to amnion layer, and are arising by epiblast, this sugest that the hAEC have characteristics of epiblast cells, in other words, characteristcs of pluripotent stem cells. Here we describe obtaining human amnion tissue and identifying pluripotent markers by immunofluorescence.

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AIMS: This study aimed to evaluate and describe the functional differences of cultivable bacteria and fungi inhabiting the leaves of Gevuina avellana Mol. (Proteaceae) in an urban area with high levels of air pollution and in a native forest in the southern Andes. METHODS AND RESULTS: Phyllosphere microorganisms were isolated from the leaves of G. avellana, their plant growth-promoting capabilities were estimated along with their biocontrol potential and tolerance to metal(loid)s. Notably, plants from the urban area showed contrasting culturable leaf-associated microorganisms compared to those from the native area. The tolerance to metal(loid)s in bacteria range from 15 to 450 mg l-1 of metal(loid)s, while fungal strains showed tolerance from 15 to 625 mg l-1, being especially higher in the isolates from the urban area. Notably, the bacterial strain Curtobacterium flaccumfaciens and the fungal strain Cladosporium sp. exhibited several plant-growth-promoting properties along with the ability to inhibit the growth of phytopathogenic fungi. CONCLUSIONS: Overall, our study provides evidence that culturable taxa in G. avellana leaves is directly influenced by the sampling area. This change is likely due to the presence of atmospheric pollutants and diverse microbial symbionts that can be horizontally acquired from the environment.

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The negative impacts of climate change on native forest ecosystems have created challenging conditions for the sustainability of natural forest regeneration. These challenges arise primarily from abiotic stresses that affect the early stages of forest tree development. While there is extensive evidence on the diversity of juvenile microbial symbioses in agricultural and fruit crops, there is a notable lack of reports on native forest plants. This review aims to summarize the critical studies conducted on the diversity of juvenile plant-microbe interactions in forest plants and to highlight the main benefits of beneficial microorganisms in overcoming environmental stresses such as drought, high and low temperatures, metal(loid) toxicity, nutrient deficiency, and salinity. The reviewed studies have consistently demonstrated the positive effects of juvenile plant-microbiota interactions and have highlighted the potential beneficial attributes to improve plantlet development. In addition, this review discusses the beneficial attributes of managing juvenile plant-microbiota symbiosis in the context of native forest restoration, including its impact on plant responses to phytopathogens, promotion of nutrient uptake, facilitation of seedling adaptation, resource exchange through shared hyphal networks, stimulation of native soil microbial communities, and modulation of gene and protein expression to enhance adaptation to adverse environmental conditions.

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Abstract A novel, simple and sensitive high-performance liquid chromatography with fluorescence detection method was developed and validated for the characterization of the preclinical pharmacokinetics of melatonin under pregnant conditions. Plasma samples (25 µL) were treated with 30 µL of ethanol absolute (containing the internal standard, IS). After a centrifugation process, aliquots of supernant (5 µL) were injected into the chromatographic system. Compounds were eluted on a Xbridge C18 (150 mm x 4.6 mm i.d., 5 µm particle size) maintained at 30°C. The mobile phase consisted in a mixture of aqueous solution of 0.4% phosphoric acid and acetonitrile (70:30 v/v). The wavelengths were set at 305 nm (excitation) and 408 nm (emission) and the total analysis time was 8 min/sample. All validation tests were obtained with accuracy and precision, according to FDA guidelines, over the concentration range of 0.005-20 µg/mL. Pharmacokinetic study showed that melatonin systemic exposure increased from day 14, with a significant difference at 19 days of gestation compared to the control group. Our findings suggest a decreased metabolism of melatonin as result of temporary physiological changes that occur throughout pregnancy. However, other maternal physiological changes cannot be ruled out.

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Cuban rice cultivars INCA LP-5 and INCA LP-7 are widely distributed in Cuba and Caribbean countries. Although there are studies about rhizospheric bacteria associated with these cultivars, there are no reports about their seed-associated bacteria. This study aimed to isolate endophytic bacteria from rice seeds and select those with the greatest plant growth-promoting traits. A total of nineteen bacterial strains from the genera Pantoea, Bacillus, Paenibacillus, and Pseudomonas were isolated from the husk and endosperm of rice seeds. The strains Pantoea sp. S5-1, Pseudomonas sp. S5-38, and Pseudomonas sp. S7-1 were classified as the most promissory to increase rice growth as they demonstrated the presence of multiple plant growth-promoting traits such as the production of auxins, phosphate, and potassium solubilization, the production of siderophores, and the inhibition of the phytopathogen Pyricularia oryzae. The inoculation of strains of Pantoea sp. and Pseudomonas spp. in rice improves the height, root length, fresh weight, and dry weight of the shoot and root after 21 days post-inoculation in hydroponic assays. This study constitutes the first report on Cuban rice cultivars about the presence of endophytes in seeds and their potential to promote seedling growth. Pantoea sp. S5-1, Pseudomonas sp. S5-38, and Pseudomonas sp. S7-1 were selected as the more promising strains for the development of bio-stimulators or bio-inoculants for Cuban rice crops.

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INTRODUCTION: Chorioamnionitis is an adverse condition in human pregnancy caused by many bacterial pathogens including Escherichia coli (E. coli); which has been associated with higher risk of preterm birth. We recently reported that human maternal decidua (MDec) tissue responds to E. coli infection by secreting extracellular heat-shock proteins (eHsp)-60, -70 and interlukin-1ß (IL-1ß). Previous studies have shown that progesterone (P4) regulates the immune response, but it is unknown whether P4 inhibits the secretion of eHsp. The aim of this investigation was to determine the role of P4 on the secretion of eHsp-27, -60, -70 and IL-1ß in MDec after 3, 6, and 24 h of E. coli infection. METHODS: Nine human feto-maternal interface (HFMi) tissues were included and mounted in the Transwell culture system. Only the maternal decidua (MDec) was stimulated for 3, 6 and 24 h with E. coli alone or in combination with progesterone and RU486. After each treatment, the HFMi tissue was recovered to determine histological changes and the culture medium recovered to evaluate the levels of eHsp-27, -60, -70 and IL-1ß by ELISA and mRNA expression by RT-PCR. RESULTS: No structural changes were observed in the HFMi tissue treated with P4 and RU486. However, stimulation with E. coli produces diffuse inflammation and ischemic necrosis. E. coli induced infection decreases, in time- and dose-dependent manner, eHsp-27 and increases eHsp-60, eHsp-70 and IL-1ß levels. In contrast, incubation of HFMi tissue with E. coli + P4 reversed eHsp and IL-1ß secretion levels relative to E. coli stimulation group but not relative to the control group. The same profile was observed on the expression of eHsp-27 and eHsp-60. DISCUSSION: we found that progesterone modulates the anti-inflammatory (eHsp-27) and pro-inflammatory (eHsp-60 and eHsp-70) levels of eHsp induced by E. coli infection in human choriodecidual tissue. eHsp-60 and eHsp-70 levels were not completely reversed; maintaining the secretion of IL-1ß, which has been associated with adverse events during pregnancy.

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Equine placentitis is characterized by infection and inflammation of the placenta. Different biomarkers associated with this inflammatory response have been evaluated in experimentally induced equine placentitis, but not in pregnant mares with spontaneous placentitis. The aim of the current study was to determine the concentration of eIL-1ß and the activity of proMMP-2 and proMMP-9 in the serum of healthy mares and mares with placentitis on days 240 and 320 of gestation to explore whether these biomarkers are associated with equine maternal placentitis and/or with the birth of an infected or inviable foals. Serum samples were collected from sixteen pregnant English Thoroughbred mares, retrospectively classified as follows: (1) healthy mares with full-term gestation; and (2) mares with ultrasonographic signs of placentitis. The health of each foal was examined at birth, and it was decided to classify the cases into four groups: (1) healthy mares delivering a healthy foals (HM-HF, n = 6); (2) mares with USP delivering a healthy foal (USP-HF, n = 3); (3) mares with USP delivering a live septic foal (USP-LSeF, n = 4); and (4) mares with USP delivering a dead foal (USP-DF, n = 3). eIL-1ß was quantified by ELISA, and proMMP-2 and proMMP-9 activity by gelatin zymography electrophoresis. In healthy mares, the serum concentrations of eIL-1ß underwent a significant 16.5-fold increase from day 240 to day 320 of gestation. Although similar results were found in the mares with ultrasonographic signs of placentitis that delivered a healthy foal, those delivering a live septic or nonviable foal exhibited much higher concentrations of eIL-1ß. proMMP-2 and proMMP-9 activity was not associated with maternal placentitis, foal infection, or death. Hence, the presence of placentitis severe enough to affect the health of the foal can be confirmed or discarded by determining the eIL-1ß concentration in mares that have shown ultrasonographic signs of placentitis.

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Preeclampsia (PE) occurs annually in 8% of pregnancies. Patients without risk factors represent 10% of these. There are currently no first-trimester biochemical markers that accurately predict PE. An increase in serum 60- and 70-KDa extracellular heat shock proteins (eHsp) has been shown in patients who developed PE at 34 weeks. We sought to determine whether there is a relationship between first-trimester eHsp and the development of PE. This was a prospective cohort study performed at a third level hospital in Mexico City from 2019 to 2020. eHsp levels were measured during the first-trimester ultrasound in singleton pregnancies with no comorbidities. First-trimester eHsp levels and biochemical parameters of organ dysfunction were compared between patients who developed preeclampsia and those who did not. All statistical analyses and model of correlation (r) between eHsp and clinical parameter were performed using bootstrapping R-software. p-values <0.05 were considered significant. The final analysis included 41 patients. PE occurred in 11 cases. eHsp-60 and eHsp-70 were significantly higher at 12 weeks in patients who developed PE (p = 0.001), while eHsp-27 was significantly lower (p = 0.004). Significant differences in first-trimester eHsp concentration suggest that these are possible early biomarkers useful for the prediction of PE.

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