Parkinson’s disease (PD) is the second most common neurodegenerative disease with gradual loss of dopaminergic neurons. Despite extensive research in the past decades, the etiology of PD remains ...elusive. Nevertheless, multiple lines of evidence suggest that oxidative stress is one of the common causes in the pathogenesis of PD. It has also been suggested that heavy metal-associated oxidative stress may be implicated in the etiology and pathogenesis of PD. Here we review the roles of redox metals, including iron, copper and cobalt, in PD. Iron is a highly reactive element and deregulation of iron homeostasis is accompanied by concomitant oxidation processes in PD. Copper is a key metal in cell division process, and it has been shown to have an important role in neurodegenerative diseases such as PD. Cobalt induces the generation of reactive oxygen species (ROS) and DNA damage in brain tissues.
Iron (Fe) deficiency is a world-wide nutritional disorder in both plants and humans, resulting from its restricted bioavailability for plants and, subsequently, low Fe concentration in edible plant ...parts. Plants have evolved sophisticated mechanisms to alleviate Fe deficiency, with the aim of recalibrating metabolic fluxes and maintaining cellular Fe homeostasis. To analyze condition-sensitive changes in precursor mRNA (pre-mRNA) splicing pattern, we mapped the transcriptome of Fe-deficient and Fe-sufficient Arabidopsis (Arabidopsis thaliana) roots using the RNA sequencing technology and a newly developed software toolbox, the Read Analysis & Comparison Kit in Java (RACKJ). In alternatively spliced genes, stress-related Gene Ontology categories were overrepresented, while housekeeping cellular functions were mainly transcriptionally controlled. Fe deficiency increased the complexity of the splicing pattern and triggered the differential alternative splicing of 313 genes, the majority of which had differentially retained introns. Several genes with important functions in Fe acquisition and homeostasis were both differentially expressed and differentially alternatively spliced upon Fe deficiency, indicating a complex regulation of gene activity in Fe-deficient conditions. A comparison with a data set for phosphate-deficient plants suggests that changes in splicing patterns are nutrient specific and not or not chiefly caused by stochastic fluctuations. In sum, our analysis identified extensive posttranscriptional control, biasing the abundance and activity of proteins in a condition-dependent manner. The production of a mixture of functional and nonfunctional transcripts may provide a means to fine-tune the abundance of transcripts with critical importance in cellular Fe homeostasis. It is assumed that differential gene expression and nutrient deficiency-induced changes in pre-mRNA splicing represent parallel, but potentially interacting, regulatory mechanisms.
The vast burden of cryptococcal meningitis occurs in immunosuppressed patients, driven by HIV, and is caused by Cryptococcus neoformans var. grubii. We previously reported cryptococcal meningitis in ...Vietnam arising atypically in HIV uninfected, apparently immunocompetent patients, caused by a single amplified fragment length polymorphism (AFLP) cluster of C. neoformans var. grubii (VNIγ). This variant was less common in HIV infected individuals; it remains unclear why this lineage is associated with apparently immunocompetent patients. To study this host tropism we aimed to further our understanding of clinical phenotype and genomic variation within Vietnamese C. neoformans var. grubii. After performing MLST on C. neoformans clinical isolates we identified 14 sequence types (STs); ST5 correlated with the VNIγ cluster. We next compared clinical phenotype by lineage and found HIV infected patients with cryptococcal meningitis caused by ST5 organisms were significantly more likely to have lymphadenopathy (11% vs. 4%, p = 0.05 Fisher's exact test) and higher blood lymphocyte count (median 0.76 versus 0.55 X109 cells/L, p = 0.001, Kruskal-Wallis test). Furthermore, survivors of ST5 infections had evidence of worse disability outcomes at 70 days (72.7% (40/55) in ST5 infections versus 57.1% (52/91) non-ST5 infections (OR 2.11, 95%CI 1.01 to 4.41), p = 0.046). To further investigate the relationship between strain and disease phenotype we performed genome sequencing on eight Vietnamese C. neoformans var. grubii. Eight genome assemblies exhibited >99% nucleotide sequence identity and we identified 165 kbp of lineage specific to Vietnamese isolates. ST5 genomes harbored several strain specific regions, incorporating 19 annotated coding sequences and eight hypothetical proteins. These regions included a phenolic acid decarboxylase, a DEAD-box ATP-dependent RNA helicase 26, oxoprolinases, a taurine catabolism dioxygenase, a zinc finger protein, membrane transport proteins and various drug transporters. Our work outlines the complexity of genomic pathogenicity in cryptococcal infections and identifies a number of gene candidates that may aid the disaggregation of the pathways associated with the pathogenesis of Cryptococcus neoformans var. grubii.
Macrophages exhibit diverse phenotypes and functions; they are also a major cell type infiltrating chronically rejected allografts. The exact phenotypes and roles of macrophages in chronic graft loss ...remain poorly defined. In the present study, we used a mouse heart transplant model to examine macrophages in chronic allograft rejection. We found that treatment of C57BL/6 mice with CTLA4 immunoglobulin fusion protein (CTLA4‐Ig) prevented acute rejection of a Balb/c heart allograft but allowed chronic rejection to develop over time, characterized by prominent neointima formation in the graft. There was extensive macrophage infiltration in the chronically rejected allografts, and the graft‐infiltrating macrophages expressed markers associated with M2 cells but not M1 cells. In an in vitro system in which macrophages were polarized into either M1 or M2 cells, we screened phenotypic differences between M1 and M2 cells and identified purinergic receptor P2X7 (P2x7r), an adenosine triphosphate (ATP)–gated ion channel protein that was preferentially expressed by M2 cells. We further showed that blocking the P2x7r using oxidized ATP (oATP) inhibited M2 induction in a dose‐dependent fashion in vitro. Moreover, treatment of C57BL/6 recipients with the P2x7r antagonist oATP, in addition to CTLA4‐Ig treatment, inhibited graft‐infiltrating M2 cells, prevented transplant vasculopathy, and induced long‐term heart allografts survival. These findings highlight the importance of the P2x7r–M2 axis in chronic rejection and establish P2x7r as a potential therapeutic target in suppression of chronic rejection.
The authors demonstrate an association between chronic heart allograft rejection and preferential enrichment of M2 macrophages in grafts that express the purinergic receptor P2X7, and demonstrate a therapeutic potential for a P2X7 receptor antagonist. See the editorial from Baldwin and Morelli on page 2510.
Early detection of cancer offers the opportunity to identify candidates when curative treatments are achievable. The THUNDER study (THe UNintrusive Detection of EaRly-stage cancers, NCT04820868) ...aimed to evaluate the performance of enhanced linear-splinter amplification sequencing, a previously described cell-free DNA (cfDNA) methylation-based technology, in the early detection and localization of six types of cancers in the colorectum, esophagus, liver, lung, ovary, and pancreas.
A customized panel of 161 984 CpG sites was constructed and validated by public and in-house (cancer: n = 249; non-cancer: n = 288) methylome data, respectively. The cfDNA samples from 1693 participants (cancer: n = 735; non-cancer: n = 958) were retrospectively collected to train and validate two multi-cancer detection blood test (MCDBT-1/2) models for different clinical scenarios. The models were validated on a prospective and independent cohort of age-matched 1010 participants (cancer: n = 505; non-cancer: n = 505). Simulation using the cancer incidence in China was applied to infer stage shift and survival benefits to demonstrate the potential utility of the models in the real world.
MCDBT-1 yielded a sensitivity of 69.1% (64.8%-73.3%), a specificity of 98.9% (97.6%-99.7%), and tissue origin accuracy of 83.2% (78.7%-87.1%) in the independent validation set. For early-stage (I-III) patients, the sensitivity of MCDBT-1 was 59.8% (54.4%-65.0%). In the real-world simulation, MCDBT-1 achieved a sensitivity of 70.6% in detecting the six cancers, thus decreasing late-stage incidence by 38.7%-46.4%, and increasing 5-year survival rate by 33.1%-40.4%, respectively. In parallel, MCDBT-2 was generated at a slightly low specificity of 95.1% (92.8%-96.9%) but a higher sensitivity of 75.1% (71.9%-79.8%) than MCDBT-1 for populations at relatively high risk of cancers, and also had ideal performance.
In this large-scale clinical validation study, MCDBT-1/2 models showed high sensitivity, specificity, and accuracy of predicted origin in detecting six types of cancers.
•MCDBT-1 had a sensitivity of 69.1% and a specificity of 98.9% in detecting six cancers.•In the real world, MCDBT-1 decreased late-stage incidence by 38.7%-46.4% and increased 5-year survival rate by 33.1%-40.4%.•In parallel, MCDBT-2 was set at a lower specificity but a higher sensitivity than MCDBT-1 and had an ideal performance.
X-linked agammaglobulinemia (XLA) has been associated with a broad range of infections, but enteroviral disease represents one of the most damaging infections. The risk of enteroviral infection in ...XLA is lower now than in the setting of intramuscular immunoglobulin or in patients without immunoglobulin replacement, but the rate of infection has not declined significantly in the era of intravenous immunoglobulin replacement. Enteroviruses can cause inflammation of nearly every organ, but in XLA, infections often manifest as dermatomyositis or chronic meningoencephalitis. Difficulty and delay in recognizing symptoms and lack of specific therapy contribute to the poor outcomes. Furthermore, cerebrospinal fluid detection of enteroviruses is not very sensitive. Reluctance to perform brain biopsies can lead to significant delays. The other feature compromising outcomes is the lack of specific therapy. High-dose peripheral and intraventricular immunoglobulin have been used, but failure is still common. New antienteroviral drugs are in development and show promise for immunodeficient patients with life-threatening infections with enterovirus.
To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with secondary acute myeloid leukemia (sAML) .
In this multicenter, ...retrospective clinical study, adult patients aged ≥18 years who underwent allo-HSCT for sAML at four centers of the Zhejiang Hematopoietic Stem Cell Transplantation Collaborative Group from January 2014 to November 2022 were included, and the efficacy and prognostic factors of allo-HSCT were analyzed.
A total of 95 patients were enrolled; 66 (69.5%) had myelodysplastic syndrome-acute myeloid leukemia (MDS-AML) , 4 (4.2%) had MDS/MPN-AML, and 25 (26.3%) had therapy-related AML (tAML) . The 3-year CIR, LFS, and overall survival (OS) rates were 18.6% (95%
10.2%-27.0%) , 70.6% (95%
60.8%-80.4%) , and 73.3% (95%
63.9%-82.7%) , respectively. The 3-year CIRs of the M-AML group (including MDS-AML and MDS/MPN-AML) and the tAML group were 20.0% and 16.4%, respectively (
=0.430) . The 3-year LFSs were 68.3% and 75.4%, respectivel
In the field of tuberculosis (TB), Community Healthcare Workers (CHWs) have been engaged for advocacy, case detection, and patient support in a wide range of settings. Estimates predict large-scale ...shortfalls of healthcare workers in low- and middle-income settings by 2030 and strategies are needed to optimize the health workforce to achieve universal availability and accessibility of healthcare. In 2018, the World Health Organization (WHO) published guidelines on best practices for CHW engagement, and identified remaining knowledge gaps. Stop TB Partnership's TB REACH initiative has supported interventions using CHWs to deliver TB care in over 30 countries, and utilized the same primary indicator to measure project impact at the population-level for all TB active case finding projects, which makes the results comparable across multiple settings. This study compiled 10 years of implementation data from the initiative's grantee network to begin to address key knowledge gaps in CHW networks.
We conducted a cross-sectional study analyzing the TB REACH data repository (n = 123) and primary survey responses (n = 50) of project implementers. We designed a survey based on WHO guidelines to understand projects' practices on CHW recruitment, training, activities, supervision, compensation, and sustainability. We segmented projects by TB notification impact and fitted linear random-effect regression models to identify practices associated with higher changes in notifications.
Most projects employed CHWs for advocacy alongside case finding and holding activities. Model characteristics associated with higher project impact included incorporating e-learning in training and having the prospect of CHWs continuing their responsibilities at the close of a project. Factors that trended towards being associated with higher impact were community-based training, differentiated contracts, and non-monetary incentives.
In line with WHO guidelines, our findings emphasize that successful implementation approaches provide CHWs with comprehensive training, continuous supervision, fair compensation, and are integrated within the existing primary healthcare system. However, we encountered a great degree of heterogeneity in CHW engagement models, resulting in few practices clearly associated with higher notifications.
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