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RESUMO O estudo das relações entre o solo e a floresta tem se mostrado importante para a compreensão, conservação e manejo destes recursos. Além disso, se constitui em instrumento valioso para o planejamento do território. A região ao norte de Manaus faz parte de um sub-domínio ecológico, onde as características edáficas e vegetacionais mostram diferenças ao longo de platôs, vertentes intermediárias e fundos de vales. Com o objetivo de avaliar o padrão destas mudanças, foram feitas descrições morfológicas de oito perfis de solo, em duas toposequências. Ao lado de cada perfil, foi feito também o estudo de um transecto, para a caracterização do tipo florestal presente, com o registro do nome vulgar e coleta de material botânico para posterior identificação. No sentido do platô para as posições mais baixas do relevo, se observa uma diferenciação da morfologia do solo com um aumento gradual no percentual de areia. As características edáficas mostram-se cada vez mais limitantes para o crescimento vegetal. No platô os solos apresentam uma textura argilosa ao longo de todo o perfil, tomando-se franco argilo arenoso a argilo arenoso nas vertentes, até chegar ao nível mais baixo da paisagem, onde os perfis se apresentam arenosos. Os resultados mostram também uma diferenciação progressiva no tipo de vegetação. A área basal decresce no sentido do platô para as áreas mais baixas. As florestas presentes em ambientes hídromórficos apresentam também uma relação estreita entre o tipo vegetacional e as características morfológicas do solo. São propostos oito tipos de paisagens florestais, que deverão subsidiar o planejamento, as intervenções e o manejo dos recursos naturais presentes na região.

Sulfur mustard (SM) is a highly toxic chemical warfare agent. Exposure to SM results in various pathologies including skin lesions with subsequent impaired wound healing. To date, there are no effective treatments available. Here we discover a SM-triggered pathomechanism involving miR-497-5p and its target survivin which contributes to keratinocyte dysfunction. Transcriptome analysis using RNA-seq in normal human epidermal keratinocytes (NHEK) revealed that SM evoked differential expression of 1896 mRNAs and 25 miRNAs with many of these RNAs known to be involved in keratinocyte function and wound healing. We demonstrated that keratinocyte differentiation and proliferation were efficiently regulated by miRNAs induced in skin cells after exposure to SM. The inhibition of miR-497-5p counteracted SM-induced premature differentiation and stimulated proliferation of NHEK. In addition, we showed that microneedle-mediated transdermal application of lipid-nanoparticles containing miR-497-5p inhibitor restored survivin biosynthesis and cellular functionality upon exposure to SM using human skin biopsies. Our findings expand the current understanding of SM-associated molecular toxicology in keratinocytes and highlight miR-497-5p as feasible clinical target for specific skin therapy in SM-exposed patients and beyond., (© 2024. The Author(s).)

Leaf parsley growth and productivity are often affected by pathogen infection. Root-knot nematodes of the genus Meloiogyne are common pathogens reported on leaf parsley. The response of leaf parsley to Meloidogyne species in tropical and subtropical regions is quite known, while in temperate regions, comparable information is still scarce. In this study, we evaluated the host status and response of three flat-leaf (Laica, Laura, Gigante d'Italia) and three curly-leaf (Grüne Perle, Orfeo, Sombre) parsley cultivars to Meloidogyne species from temperate regions, i.e., M. hapla , M. chitwoodi , and M. fallax , as well as to the southern root-knot nematode M. incognita . Evaluation was based on measuring plant biomass and nematode reproduction nine weeks after nematode inoculation. Our results showed that all four Meloidogyne species did not cause the reduction in leaf parsley growth under the given experimental conditions. Regarding the host status of leaf parsley cultivars for Meloidogyne , results were variable. All six parsley cultivars were found to be good hosts for M. hapla . Regarding M. chitwoodi , the host status could not be clarified properly; however, each cultivar allowed nematode reproduction at least in one experiment. For M. fallax , flat-leaf parsley turned out to be less susceptible than curly-leaf parsley; and for M. incognita , Orfeo, Laura, and Laica were classified as good hosts, Grüne Perle and Sombre as poor hosts, and Gigante d'Italia as a non-host. Amongst all tested cultivars, Gigante d'Italia was found to be the least susceptible cultivar due to its poor host status for M. chitwoodi and non-host status for M. fallax and M. incognita . Infection with M. hapla , M. chitwoodi , and M. incognita , but not with M. fallax , resulted in distinct gall formation on the roots of all six leaf parsley cultivars.

Narcolepsy is a rare cause of hypersomnolence and may be associated or not with cataplexy, i.e. sudden muscle weakness. These forms are designated narcolepsy-type 1 (NT1) and -type 2 (NT2), respectively. Notable characteristics of narcolepsy are that most patients carry the HLA-DQB1*06:02 allele and NT1-patients have strongly decreased levels of hypocretin-1 (synonym orexin-A) in the cerebrospinal fluid (CSF). The pathogenesis of narcolepsy is still not completely understood but the strong HLA-bias and increased frequencies of CD4 + T cells reactive to hypocretin in the peripheral blood suggest autoimmune processes in the hypothalamus. Here we analyzed the transcriptomes of CSF-cells from twelve NT1 and two NT2 patients by single cell RNAseq (scRNAseq). As controls, we used CSF cells from patients with multiple sclerosis, radiologically isolated syndrome, and idiopathic intracranial hypertension. From 27,255 CSF cells, we identified 20 clusters of different cell types and found significant differences in three CD4 + T cell and one monocyte clusters between narcolepsy and multiple sclerosis patients. Over 1000 genes were differentially regulated between patients with NT1 and other diseases. Surprisingly, the most strongly upregulated genes in narcolepsy patients as compared to controls were coding for the genome-encoded MTRNR2L12 and MTRNR2L8 peptides, which are homologous to the mitochondria-encoded HUMANIN peptide that is known playing a role in other neurological diseases including Alzheimer's disease., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: Lung transplant recipients are at increased risk of severe disease following infection with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) due to high-dose immunosuppressive drugs and the lung is the main organ affected by Coronavirus disease 2019 (COVID-19). Several studies have confirmed increased SARS-CoV-2-related mortality and morbidity in patients living with lung allografts; however, detailed immunological studies of patients with SARS-CoV-2 infection in the early phase following transplantation remain scarce., Methods: We investigated patients who were infected with SARS-CoV-2 in the early phase (18-103 days) after receiving double-lung allografts (n = 4, LuTx) in comparison to immunocompetent patients who had not received solid organ transplants (n = 88, noTx). We analyzed SARS-CoV-2-specific antibody responses against the SARS-CoV-2 spike and nucleocapsid proteins using enzyme-linked immunosorbent assays (ELISA), chemiluminescence immunoassays (CLIA), and immunoblot assays. T cell responses were investigated using Elispot assays., Results: One LuTx patient suffered from persistent infection with fatal outcome 122 days post-infection despite multiple interventions including remdesivir, convalescent plasma, and the monoclonal antibody bamlanivimab. Two patients experienced clinically mild disease with prolonged viral shedding (47 and 79 days), and one patient remained asymptomatic. Antibody and T cell responses were significantly reduced or undetectable in all LuTx patients compared to noTx patients., Conclusion: Patients in the early phase following lung allograft transplantation are vulnerable to infection with SARS-CoV-2 due to impaired immune responses. This patient population should be vaccinated before LuTx, protected from infection post-LuTx, and in case of infection treated generously with currently available interventions., (© 2023. The Author(s).)

Innate antiviral factors are essential for effective defense against viral pathogens. However, the identity of major restriction mechanisms remains elusive. Current approaches to discover antiviral factors usually focus on the initial steps of viral replication and are limited to a single round of infection. Here, we engineered libraries of >1500 replication-competent HIV-1 constructs each expressing a single gRNAs to target >500 cellular genes for virus-driven discovery of antiviral factors. Passaging in CD4 + T cells robustly enriched HIV-1 encoding sgRNAs against GRN, CIITA, EHMT2, CEACAM3, CC2D1B and RHOA by >50-fold. Using an HIV-1 library lacking the accessory nef gene, we identified IFI16 as a Nef target. Functional analyses in cell lines and primary CD4 + T cells support that the HIV-driven CRISPR screen identified restriction factors targeting virus entry, transcription, release and infectivity. Our HIV-guided CRISPR technique enables sensitive discovery of physiologically relevant cellular defense factors throughout the entire viral replication cycle., (© 2024. The Author(s).)

Under-reporting of COVID-19 and the limited information about circulating SARS-CoV-2 variants remain major challenges for many African countries. We analyzed SARS-CoV-2 infection dynamics in Addis Ababa and Jimma, Ethiopia, focusing on reinfection, immunity, and vaccination effects. We conducted an antibody serology study spanning August 2020 to July 2022 with five rounds of data collection across a population of 4723, sequenced PCR-test positive samples, used available test positivity rates, and constructed two mathematical models integrating this data. A multivariant model explores variant dynamics identifying wildtype, alpha, delta, and omicron BA.4/5 as key variants in the study population, and cross-immunity between variants, revealing risk reductions between 24% and 69%. An antibody-level model predicts slow decay leading to sustained high antibody levels. Retrospectively, increased early vaccination might have substantially reduced infections during the delta and omicron waves in the considered group of individuals, though further vaccination now seems less impactful., (© 2024. The Author(s).)

The SARS-CoV-2 pandemic has highlighted the need to better define in-hospital transmissions, a need that extends to all other common infectious diseases encountered in clinical settings. To evaluate how whole viral genome sequencing can contribute to deciphering nosocomial SARS-CoV-2 transmission 926 SARS-CoV-2 viral genomes from 622 staff members and patients were collected between February 2020 and January 2021 at a university hospital in Munich, Germany, and analysed along with the place of work, duration of hospital stay, and ward transfers. Bioinformatically defined transmission clusters inferred from viral genome sequencing were compared to those inferred from interview-based contact tracing. An additional dataset collected at the same time at another university hospital in the same city was used to account for multiple independent introductions. Clustering analysis of 619 viral genomes generated 19 clusters ranging from 3 to 31 individuals. Sequencing-based transmission clusters showed little overlap with those based on contact tracing data. The viral genomes were significantly more closely related to each other than comparable genomes collected simultaneously at other hospitals in the same city (n = 829), suggesting nosocomial transmission. Longitudinal sampling from individual patients suggested possible cross-infection events during the hospital stay in 19.2% of individuals (14 of 73 individuals). Clustering analysis of SARS-CoV-2 whole genome sequences can reveal cryptic transmission events missed by classical, interview-based contact tracing, helping to decipher in-hospital transmissions. These results, in line with other studies, advocate for viral genome sequencing as a pathogen transmission surveillance tool in hospitals., (© 2024. The Author(s).)

The panel discussion presented at the New York Psychoanalytic Society and Institute's 1066th Scientific Meeting held on June 8, 2023, takes up aging and dying of an analyst and their impact on patients and on the nature of analytic process. Participants reflect on conflicts and challenges arising with more analysts and patients living to an advanced age, on the unregulated nature of analysts' retirement, and on multilayered meanings of analysts' ethical commitment to their work.

The response to proteotoxic stresses such as heat shock allows organisms to maintain protein homeostasis under changing environmental conditions. We asked what happens if an organism can no longer react to cytosolic proteotoxic stress. To test this, we deleted or depleted, either individually or in combination, the stress-responsive transcription factors Msn2, Msn4, and Hsf1 in Saccharomyces cerevisiae. Our study reveals a combination of survival strategies, which together protect essential proteins. Msn2 and 4 broadly reprogram transcription, triggering the response to oxidative stress, as well as biosynthesis of the protective sugar trehalose and glycolytic enzymes, while Hsf1 mainly induces the synthesis of molecular chaperones and reverses the transcriptional response upon prolonged mild heat stress (adaptation)., (© 2024 The Authors. FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

T follicular helper (T FH ) cells are essential for effective antibody responses, but deciphering the intrinsic wiring of mouse T FH cells has long been hampered by the lack of a reliable protocol for their generation in vitro. We report that transforming growth factor-β (TGF-β) induces robust expression of T FH hallmark molecules CXCR5 and Bcl6 in activated mouse CD4 + T cells in vitro. TGF-β-induced mouse CXCR5 + T FH cells are phenotypically, transcriptionally, and functionally similar to in vivo-generated T FH cells and provide critical help to B cells. The study further reveals that TGF-β-induced CXCR5 expression is independent of Bcl6 but requires the transcription factor c-Maf. Classical TGF-β-containing T helper 17 (T H 17)-inducing conditions also yield separate CXCR5 + and IL-17A-producing cells, highlighting shared and distinct cell fate trajectories of T FH and T H 17 cells. We demonstrate that excess IL-2 in high-density T cell cultures interferes with the TGF-β-induced T FH cell program, that T FH and T H 17 cells share a common developmental stage, and that c-Maf acts as a switch factor for T FH versus T H 17 cell fates in TGF-β-rich environments in vitro and in vivo.