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1.
Immunity ; 56(6): 1220-1238.e7, 2023 06 13.
Article in English | MEDLINE | ID: mdl-37130522

ABSTRACT

Early-life immune development is critical to long-term host health. However, the mechanisms that determine the pace of postnatal immune maturation are not fully resolved. Here, we analyzed mononuclear phagocytes (MNPs) in small intestinal Peyer's patches (PPs), the primary inductive site of intestinal immunity. Conventional type 1 and 2 dendritic cells (cDC1 and cDC2) and RORgt+ antigen-presenting cells (RORgt+ APC) exhibited significant age-dependent changes in subset composition, tissue distribution, and reduced cell maturation, subsequently resulting in a lack in CD4+ T cell priming during the postnatal period. Microbial cues contributed but could not fully explain the discrepancies in MNP maturation. Type I interferon (IFN) accelerated MNP maturation but IFN signaling did not represent the physiological stimulus. Instead, follicle-associated epithelium (FAE) M cell differentiation was required and sufficient to drive postweaning PP MNP maturation. Together, our results highlight the role of FAE M cell differentiation and MNP maturation in postnatal immune development.


Subject(s)
M Cells , Peyer's Patches , Intestines , Intestine, Small , Cell Differentiation , Intestinal Mucosa
2.
Mol Cell ; 78(4): 725-738.e4, 2020 05 21.
Article in English | MEDLINE | ID: mdl-32277910

ABSTRACT

Concomitant with DNA replication, the chromosomal cohesin complex establishes cohesion between newly replicated sister chromatids. Several replication-fork-associated "cohesion establishment factors," including the multifunctional Ctf18-RFC complex, aid this process in as yet unknown ways. Here, we show that Ctf18-RFC's role in sister chromatid cohesion correlates with PCNA loading but is separable from its role in the replication checkpoint. Ctf18-RFC loads PCNA with a slight preference for the leading strand, which is dispensable for DNA replication. Conversely, the canonical Rfc1-RFC complex preferentially loads PCNA onto the lagging strand, which is crucial for DNA replication but dispensable for sister chromatid cohesion. The downstream effector of Ctf18-RFC is cohesin acetylation, which we place toward a late step during replication maturation. Our results suggest that Ctf18-RFC enriches and balances PCNA levels at the replication fork, beyond the needs of DNA replication, to promote establishment of sister chromatid cohesion and possibly other post-replicative processes.


Subject(s)
Cell Cycle Proteins/metabolism , Chromatids/physiology , Chromosomal Proteins, Non-Histone/metabolism , Chromosomes, Fungal/physiology , DNA Replication , Proliferating Cell Nuclear Antigen/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/genetics , Acetyltransferases/genetics , Acetyltransferases/metabolism , Cell Cycle Proteins/genetics , Chromosomal Proteins, Non-Histone/genetics , Chromosome Segregation , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Proliferating Cell Nuclear Antigen/genetics , Replication Protein C/genetics , Replication Protein C/metabolism , Saccharomyces cerevisiae/growth & development , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Cohesins
3.
EMBO Rep ; 25(10): 4131-4152, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39285248

ABSTRACT

Precise spatiotemporal regulation of gene expression is of paramount importance for eukaryotic development. The maternal-to-zygotic transition (MZT) during early embryogenesis in Drosophila involves the gradual replacement of maternally contributed mRNAs and proteins by zygotic gene products. The zygotic genome is transcriptionally activated during the first 3 hours of development, in a process known as "zygotic genome activation" (ZGA), by the orchestrated activities of a few pioneer factors. Their decisive role during ZGA has been characterized in detail, whereas the contribution of chromatin factors to this process has been historically overlooked. In this review, we aim to summarize the current knowledge of how chromatin regulation impacts the first stages of Drosophila embryonic development. In particular, we will address the following questions: how chromatin factors affect ZGA and transcriptional silencing, and how genome architecture promotes the integration of these processes early during development. Remarkably, certain chromatin marks can be intergenerationally inherited, and their presence in the early embryo becomes critical for the regulation of gene expression at later stages. Finally, we speculate on the possible roles of these chromatin marks as carriers of epialleles during transgenerational epigenetic inheritance (TEI).


Subject(s)
Chromatin , Epigenesis, Genetic , Gene Expression Regulation, Developmental , Animals , Chromatin/metabolism , Chromatin/genetics , Zygote/metabolism , Embryonic Development/genetics , Embryo, Nonmammalian/metabolism , Drosophila/genetics , Drosophila/embryology , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism
4.
Proc Natl Acad Sci U S A ; 119(11): e2114205119, 2022 03 15.
Article in English | MEDLINE | ID: mdl-35259017

ABSTRACT

SignificanceIntracellular gradients have essential roles in cell and developmental biology, but their formation is not fully understood. We have developed a computational approach facilitating interpretation of protein dynamics and gradient formation. We have combined this computational approach with experiments to understand how Polo-Like Kinase 1 (PLK-1) forms a cytoplasmic gradient in Caenorhabditis elegans embryos. Although the PLK-1 gradient depends on the Muscle EXcess-5/6 (MEX-5/6) proteins, we reveal differences in PLK-1 and MEX-5 gradient formation that can be explained by a model with two components, PLK-1 bound to MEX-5 and unbound PLK-1. Our combined approach suggests that a weak coupling between PLK-1 and MEX-5 reaction-diffusion mechanisms dictates the dynamic exchange of PLK-1 with the cytoplasm, explaining PLK-1 high diffusivity and smooth gradient.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/embryology , Caenorhabditis elegans/metabolism , Proteome , Proteomics , Animals , Embryo, Nonmammalian , Models, Biological , Monte Carlo Method , Morphogenesis , Protein Serine-Threonine Kinases , Protein Transport , Proteomics/methods
5.
Annu Rev Entomol ; 69: 355-373, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-37758223

ABSTRACT

Global trade in fresh fruit and vegetables, intensification of human mobility, and climate change facilitate fruit fly (Diptera: Tephritidae) invasions. Life-history traits, environmental stress response, dispersal stress, and novel genetic admixtures contribute to their establishment and spread. Tephritids are among the most frequently intercepted taxa at ports of entry. In some countries, supported by the rules-based trade framework, a remarkable amount of biosecurity effort is being arrayed against the range expansion of tephritids. Despite this effort, fruit flies continue to arrive in new jurisdictions, sometimes triggering expensive eradication responses. Surprisingly, scant attention has been paid to biosecurity in the recent discourse about new multilateral trade agreements. Much of the available literature on managing tephritid invasions is focused on a limited number of charismatic (historically high-profile) species, and the generality of many patterns remains speculative.


Subject(s)
Drosophila , Life History Traits , Animals , Humans , Climate Change , Nonoxynol
6.
Ecol Lett ; 27(2): e14391, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38400769

ABSTRACT

Current rates of climate change are exceeding the capacity of many plant species to track climate, thus leading communities to be in disequilibrium with climatic conditions. Plant canopies can contribute to this disequilibrium by buffering macro-climatic conditions and sheltering poorly adapted species to the oncoming climate, particularly in their recruitment stages. Here we analyse differences in climatic disequilibrium between understorey and open ground woody plant recruits in 28 localities, covering more than 100,000 m2 , across an elevation range embedding temperature and aridity gradients in the southern Iberian Peninsula. This study demonstrates higher climatic disequilibrium under canopies compared with open ground, supporting that plant canopies would affect future community climatic lags by allowing the recruitment of less arid-adapted species in warm and dry conditions, but also it endorse that canopies could favour warm-adapted species in extremely cold environments as mountain tops, thus pre-adapting communities living in these habitats to climate change.


Subject(s)
Ecosystem , Plants , Climate Change , Wood , Temperature
7.
Plant Cell Physiol ; 65(3): 350-361, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38175914

ABSTRACT

Young seedlings use nutrients stored in the seeds to grow and acquire photosynthetic potential. This process, called seedling establishment, involves a developmental phase transition from heterotrophic to autotrophic growth. Some membrane-trafficking mutants of Arabidopsis (Arabidopsis thaliana), such as the katamari2 (kam2) mutant, exhibit growth arrest during seedling development, with a portion of individuals failing to develop true leaves on sucrose-free solid medium. However, the reason for this seedling arrest is unclear. In this study, we show that seedling arrest is a temporal growth arrest response that occurs not only in kam2 but also in wild-type (WT) Arabidopsis; however, the threshold for this response is lower in kam2 than in the WT. A subset of the arrested kam2 seedlings resumed growth after transfer to fresh sucrose-free medium. Growth arrest in kam2 on sucrose-free medium was restored by increasing the gel concentration of the medium or covering the surface of the medium with a perforated plastic sheet. WT Arabidopsis seedlings were also arrested when the gel concentration of sucrose-free medium was reduced. RNA sequencing revealed that transcriptomic changes associated with the rate of seedling establishment were observed as early as 4 d after sowing. Our results suggest that the growth arrest of both kam2 and WT seedlings is an adaptive stress response and is not simply caused by the lack of a carbon source in the medium. This study provides a new perspective on an environmental stress response under unfavorable conditions during the phase transition from heterotrophic to autotrophic growth in Arabidopsis.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Humans , Arabidopsis/physiology , Arabidopsis Proteins/metabolism , Autotrophic Processes , Gene Expression Regulation, Plant , Heterotrophic Processes , Seedlings
8.
Am Nat ; 203(6): E188-E199, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38781531

ABSTRACT

AbstractAn individual's access to mates (i.e., its "mating potential") can constrain its reproduction but may also influence its fitness through effects on offspring survival. For instance, mate proximity may correspond with relatedness and lead to inbreeding depression in offspring. While offspring production and survival might respond differently to mating potential, previous studies have not considered the simultaneous effects of mating potential on these fitness components. We investigated the relationship of mating potential with both production and survival of offspring in populations of a long-lived herbaceous perennial, Echinacea angustifolia. Across 7 years and 14 sites, we quantified the mating potential of maternal plants in 1,278 mating bouts and followed the offspring from these bouts over 8 years. We used aster models to evaluate the relationship of mating potential with the number of offspring that emerged and that were alive after 8 years. Seedling emergence increased with mating potential. Despite this, the number of offspring surviving after 8 years showed no relationship to mating potential. Our results support the broader conclusion that the effect of mating potential on fitness erodes over time because of demographic stochasticity at the maternal level.


Subject(s)
Echinacea , Genetic Fitness , Reproduction , Echinacea/physiology , Seedlings/physiology , Seedlings/growth & development
9.
J Neurosci Res ; 102(6): e25359, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38859680

ABSTRACT

The blood-brain barrier (BBB) is a barrier between the circulatory system and the central nervous system (CNS), contributing to CNS protection and maintaining the brain homeostasis. Establishment of in vitro BBB models that are closer to the microenvironment of the human brain is helpful for evaluating the potential and efficiency of a drug penetrating BBB and thus the clinical application value of the drug. The in vitro BBB models not only provide great convenience for screening new drugs that can access to CNS but also help people to have a deeper study on the mechanism of substances entering and leaving the brain, which makes people have greater opportunities in the treatment of CNS diseases. Up to now, although much effort has been paid to the researches on the in vitro BBB models and many progresses have been achieved, no unified method has been described for establishing a BBB model and there is much work to do and many challenges to be faced with in the future. This review summarizes the research progresses in the establishment, evaluation, and application of in vitro BBB models.


Subject(s)
Blood-Brain Barrier , Blood-Brain Barrier/metabolism , Humans , Animals , Models, Biological
10.
J Exp Bot ; 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39031128

ABSTRACT

The plant cuticle is a complex extracellular lipid barrier that has multiple protective functions. We investigated cuticle deposition by integrating metabolomics and transcriptomics data gathered from six different maize seedling organs of four genotypes, the inbred lines B73 and Mo17, and their reciprocal hybrids. These datasets captured the developmental transition of the seedling from heterotrophic skotomorphogenic growth to autotrophic photomorphogenic growth, which is a transition that is highly vulnerable to environmental stresses. Statistical interrogation of these data reveals that the predominant determinant of cuticle composition is seedling organ type, whereas the seedling genotype has a smaller effect on this phenotype. Gene-to-metabolite associations assessed by integrated statistical analyses identified three gene networks connected with the deposition of different elements of the cuticle: a) cuticular waxes; b) monomers of lipidized cell wall biopolymers, including cutin and suberin; and c) both of these elements. These gene networks reveal three metabolic programs that appear to support cuticle deposition, including processes of chloroplast biogenesis, lipid metabolism, and molecular regulation (e.g., transcription factors, post-translational regulators and phytohormones). This study demonstrates the wider physiological metabolic context that can determine cuticle deposition and lays the groundwork for new targets for modulating properties of this protective barrier.

11.
Cytotherapy ; 26(5): 524-530, 2024 05.
Article in English | MEDLINE | ID: mdl-38441513

ABSTRACT

BACKGROUND AIMS: The relationship between blood establishments and advanced cellular therapies is evident in several European countries, with some involved in research and development and/or in manufacturing. The aim of the present study was to understand the advanced therapy medicinal product (ATMP) infrastructural, regulatory and logistic requirements needed for the Irish Blood Transfusion Service to support advanced therapeutics in Ireland. METHODS: An online survey consisting of 13 questions was distributed in a targeted manner to the identified ATMP stakeholders in Ireland, namely those working in industry, health care, regulatory agencies or education. Subject matter experts in the field were approached and interviewed to gain further insight into the relationship between blood and tissue establishments (BTEs) and ATMPs, to explore the advantages these institutions have in development and to highlight potential challenges for implementation. RESULTS: In total, 84.9% of survey respondents stated that BTEs have a role in the development of advanced therapeutics. Key BTE services identified as applicable to the ATMP sector from both surveys and interviews include the provision of starting materials for research and manufacturing, donor management, use of existing quality and traceability frameworks, product logistic strategies and Good Manufacturing Practice. Challenges for BTE expansion into the sector currently include high costs associated with ATMPs, lack of expertise in these therapies, limited therapeutic populations and no national ATMP strategic plan for Ireland. CONCLUSIONS: Blood establishments have services and expertise that can be extended into the advanced therapy sector. The existing knowledge and skill base of BTEs in Ireland should be leveraged to accelerate the development of ATMP strategies for industry and healthcare.


Subject(s)
Cell- and Tissue-Based Therapy , Humans , Ireland , Surveys and Questionnaires , Cell- and Tissue-Based Therapy/methods , Blood Banks , Blood Transfusion/methods
12.
Transfusion ; 64(6): 969-978, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38650378

ABSTRACT

BACKGROUND: With the widespread adoption of Blood Establishment Computer Systems and other Blood Collection and Transfusion Service (BCTS) clinical information systems (CIS), electronic blood donor, product, and patient data are now routinely required for clinical, regulatory, operational, and quality needs. That data are often not readily accessible for such secondary use within CIS databases, particularly for applications with significant data availability requirements such as machine learning and artificial intelligence. Data replication provides one avenue by which CIS data can be made more readily available. STUDY DESIGN AND METHODS: Members of the AABB's Information Systems Committee along with institutional information technology colleagues provided a multi-institutional viewpoint on data replication through the lens of BCTS specific use cases. Case studies of informatics offerings leveraging such technologies were also elicited. RESULTS: Six distinct use cases describe the potential role of data replication including the creation of data warehouses for frontline laboratory staff. Specific BCTS examples for each use case are presented to highlight the value of data replication, including visualization of critical inventory (O red blood cells, HLA-compatible platelets) and utilization analytics for patient blood management. Two case studies describe the approach to implement such technologies to (1) optimize staffing via laboratory workload reporting and (2) improve access to blood via antigen-negative blood product location services. DISCUSSION: Data replication and warehousing can empower BCTS analytic offerings not otherwise natively available through one's CIS to improve patient care and laboratory operations.


Subject(s)
Blood Transfusion , Humans , Blood Transfusion/methods , Data Warehousing , Blood Banks
13.
Mol Cell Biochem ; 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39251464

ABSTRACT

Scaffolds used in tissue engineering can be obtained from synthetic or natural materials, always focusing the effort on mimicking the extracellular matrix of human native tissue. In this study, a decellularization process is used to obtain an acellular, biocompatible non-cytotoxic human pericardium graft as a bio-substitute. An enzymatic and hypertonic method was used to decellularize the pericardium. Histological analyses were performed to determine the absence of cells and ensure the integrity of the extracellular matrix (ECM). In order to measure the effect of the decellularization process on the tissue's biological and mechanical properties, residual genetic content and ECM biomolecules (collagen, elastin, and glycosaminoglycan) were quantified and the tissue's tensile strength was tested. Preservation of the biomolecules, a residual genetic content below 50 ng/mg dry tissue, and maintenance of the histological structure provided evidence for the efficacy of the decellularization process, while preserving the ECM. Moreover, the acellular tissue retains its mechanical properties, as shown by the biomechanical tests. Our group has shown that the acellular pericardial matrix obtained through the super-fast decellularization protocol developed recently retains the desired biomechanical and structural properties, suggesting that it is suitable for a broad range of clinical indications.

14.
Malar J ; 23(1): 254, 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39180067

ABSTRACT

BACKGROUND: The COVID-19 pandemic-with its first reported case in Sri Lanka in March 2020-had the potential to impact the risk of re-establishing malaria, a disease which was eliminated from Sri Lanka in 2012. Post-elimination, the country remains highly vulnerable to a return of malaria on account of high vector mosquito densities and the inflow of imported malaria cases. METHODS: Parallels between COVID-19 and malaria after its elimination as health security threats were drawn, and the many ways in which the COVID-19 pandemic impacted the prevention of re-establishment of malaria programmes in the country in 2020 were examined. The implications of this experience for global health security are analysed. RESULTS: In 2020, imported malaria cases were fewer than in the previous 3 years, due to restrictions on international travel. Yet, a high level of malaria case and entomological surveillance was sustained through surveillance strategies modified to focus on quarantine centers, in response to the pandemic. As a result, more imported malaria cases were detected by active case detection than by passive surveillance. Some of the operational shifts adopted by the Anti Malaria Campaign were moving rapidly into functioning as an intersectoral player by reinforcing its collaborations with the Ministries of Aviation and Defense, switching to the use of online communication systems, and integrating and synergizing its field activities with the COVID-19 control programme. CONCLUSIONS: The experience highlights the need for disease control programmes to be agile, flexible and responsive, and underscores the importance of maintaining even a lean focal programme for diseases such as malaria after they have been eliminated. Sustaining public health leadership and robust technological capacities in communication and data management were paramount in preventing the disruption of the malaria prevention programme during the pandemic and sustaining the malaria-free status of the country.


Subject(s)
COVID-19 , Malaria , Sri Lanka/epidemiology , Humans , COVID-19/prevention & control , COVID-19/epidemiology , Malaria/prevention & control , Malaria/epidemiology , SARS-CoV-2 , Pandemics/prevention & control
15.
Malar J ; 23(1): 35, 2024 Jan 27.
Article in English | MEDLINE | ID: mdl-38281044

ABSTRACT

BACKGROUND: Sri Lanka after eliminating malaria in 2012, is in the prevention of re-establishment (POR) phase. Being a tropical country with high malariogenic potential, maintaining vigilance is important. All malaria cases are investigated epidemiologically and followed up by integrated drug efficacy surveillance (iDES). Occasionally, that alone is not adequate to differentiate Plasmodium falciparum reinfections from recrudescences. This study evaluated the World Health Organization and Medicines for Malaria Venture (MMV) recommended genotyping protocol for the merozoite surface proteins (msp1, msp2) and the glutamate-rich protein (glurp) to discriminate P. falciparum recrudescence from reinfection in POR phase. METHODS: All P. falciparum patients detected from April 2014 to December 2019 were included in this study. Patients were treated and followed up by iDES up to 28 days and were advised to get tested if they develop fever at any time over the following year. Basic socio-demographic information including history of travel was obtained. Details of the malariogenic potential and reactive entomological and parasitological surveillance carried out by the Anti Malaria Campaign to exclude the possibility of local transmission were also collected. The msp1, msp2, and glurp genotyping was performed for initial and any recurrent infections. Classification of recurrent infections as recrudescence or reinfection was done based on epidemiological findings and was compared with the genotyping outcome. RESULTS: Among 106 P. falciparum patients, six had recurrent infections. All the initial infections were imported, with a history of travel to malaria endemic countries. In all instances, the reactive entomological and parasitological surveillance had no evidence for local transmission. Five recurrences occurred within 28 days of follow-up and were classified as recrudescence. They have not travelled to malaria endemic countries between the initial and recurrent infections. The other had a recurrent infection after 105 days. It was assumed a reinfection, as he had travelled to the same malaria endemic country in between the two malaria attacks. Genotyping confirmed the recrudescence and the reinfection. CONCLUSIONS: The msp1, msp2 and glurp genotyping method accurately differentiated reinfections from recrudescence. Since reinfection without a history of travel to a malaria endemic country would mean local transmission, combining genotyping outcome with epidemiological findings will assist classifying malaria cases without any ambiguity.


Subject(s)
Frontotemporal Dementia , Malaria, Falciparum , Merozoite Surface Protein 1 , Muscular Dystrophies, Limb-Girdle , Myositis, Inclusion Body , Osteitis Deformans , Male , Humans , Merozoite Surface Protein 1/genetics , Plasmodium falciparum/genetics , Reinfection , Protozoan Proteins/genetics , Protozoan Proteins/therapeutic use , Antigens, Protozoan/genetics , Antigens, Protozoan/therapeutic use , Genotype , Glutamic Acid , Sri Lanka/epidemiology , Genetic Variation , Malaria, Falciparum/epidemiology , Malaria, Falciparum/prevention & control , Malaria, Falciparum/drug therapy , Recurrence
16.
Malar J ; 23(1): 195, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38909255

ABSTRACT

BACKGROUND: Imported malaria continues to be reported in Sri Lanka after it was eliminated in 2012, and a few progress to life-threatening severe malaria. METHODS: Data on imported malaria cases reported in Sri Lanka from 2013 to 2023 were extracted from the national malaria database maintained by the Anti Malaria Campaign (AMC) of Sri Lanka. Case data of severe malaria as defined by the World Health Organization were analysed with regard to patients' general characteristics and their health-seeking behaviour, and the latter compared with that of uncomplicated malaria patients. Details of the last three cases of severe malaria in 2023 are presented. RESULTS: 532 imported malaria cases were diagnosed over 11 years (2013-2023); 46 (8.6%) were severe malaria, of which 45 were Plasmodium falciparum and one Plasmodium vivax. Most severe malaria infections were acquired in Africa. All but one were males, and a majority (87%) were 26-60 years of age. They were mainly Sri Lankan nationals (82.6%). Just over half (56.5%) were treated at government hospitals. The average time between arrival of the person in Sri Lanka and onset of illness was 4 days. 29 cases of severe malaria were compared with 165 uncomplicated malaria cases reported from 2015 to 2023. On average both severe and uncomplicated malaria patients consulted a physician equally early (mean = 1 day) with 93.3% of severe malaria doing so within 3 days. However, the time from the point of consulting a physician to diagnosis of malaria was significantly longer (median 4 days) in severe malaria patients compared to uncomplicated patients (median 1 day) (p = 0.012) as was the time from onset of illness to diagnosis (p = 0.042). All severe patients recovered without sequelae except for one who died. CONCLUSIONS: The risk of severe malaria among imported cases increases significantly beyond 5 days from the onset of symptoms. Although patients consult a physician early, malaria diagnosis tends to be delayed by physicians because it is now a rare disease. Good access to expert clinical care has maintained case fatality rates of severe malaria at par with those reported elsewhere.


Subject(s)
Communicable Diseases, Imported , Sri Lanka/epidemiology , Humans , Male , Adult , Middle Aged , Female , Young Adult , Communicable Diseases, Imported/epidemiology , Communicable Diseases, Imported/parasitology , Communicable Diseases, Imported/diagnosis , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Aged , Adolescent , Malaria/epidemiology , Malaria/prevention & control , Disease Eradication/statistics & numerical data
17.
Am J Bot ; 111(8): e16318, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38654555

ABSTRACT

PREMISE: Numerous studies have found a positive association between dioecy and polyploidy; however, this association presents a theoretical conflict: While polyploids are predicted to benefit from self-reproduction for successful establishment, dioecious species cannot self-reproduce. We propose a theoretical framework to resolve this apparent conflict. We hypothesize that the inability of dioecious species to self-reproduce hinders their establishment as polyploids. We therefore expect that genera with many dioecious species have fewer polyploids, leading to a negative association between polyploidy and dioecy across genera. METHODS: We used three publicly available databases to determine ploidy and sexual systems for 131 genera and 546 species. We quantified (1) the relationship between the frequency of polyploid species and the frequency of dioecious species across genera, and (2) the proportion of polyploids with hermaphroditism and dioecy across species, adjusting for phylogenetic history. RESULTS: Across genera, we found a negative relationship between the proportion of polyploids and the proportion of dioecious species, a consistent trend across clades. Across all species, we found that sexual system (dioecious or not) was not associated with polyploidy. CONCLUSIONS: Polyploids are rare in genera in which the majority of species are dioecious, consistent with the theory that self-reproduction favors polyploid establishment. The low frequency of polyploidy among dioecious species indicates the association is not as widespread as previously suggested. Our findings are consistent with previous studies identifying a positive relationship between the two traits, but only if polyploidy promotes a transition to dioecy, and not the reverse.


Subject(s)
Polyploidy , Reproduction , Phylogeny , Magnoliopsida/genetics , Magnoliopsida/physiology
18.
J Pineal Res ; 76(5): e13004, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39145574

ABSTRACT

Both seed germination and subsequent seedling establishment are key checkpoints during the life cycle of seed plants, yet flooding stress markedly inhibits both processes, leading to economic losses from agricultural production. Here, we report that melatonin (MT) seed priming treatment enhances the performance of seeds from several crops, including soybean, wheat, maize, and alfalfa, under flooding stress. Transcriptome analysis revealed that MT priming promotes seed germination and seedling establishment associated with changes in abscisic acid (ABA), gibberellin (GA), and reactive oxygen species (ROS) biosynthesis and signaling pathways. Real-time quantitative RT-PCR (qRT-PCR) analysis confirmed that MT priming increases the expression levels of GA biosynthesis genes, ABA catabolism genes, and ROS biosynthesis genes while decreasing the expression of positive ABA regulatory genes. Further, measurements of ABA and GA concentrations are consistent with these trends. Following MT priming, quantification of ROS metabolism-related enzyme activities and the concentrations of H2O2 and superoxide anions (O2 -) after MT priming were consistent with the results of transcriptome analysis and qRT-PCR. Finally, exogenous application of GA, fluridone (an ABA biosynthesis inhibitor), or H2O2 partially rescued the poor germination of non-primed seeds under flooding stress. Collectively, this study uncovers the application and molecular mechanisms underlying MT priming in modulating crop seed vigor under flooding stress.


Subject(s)
Abscisic Acid , Floods , Germination , Gibberellins , Melatonin , Reactive Oxygen Species , Seedlings , Seeds , Melatonin/pharmacology , Melatonin/metabolism , Germination/drug effects , Abscisic Acid/metabolism , Gibberellins/metabolism , Reactive Oxygen Species/metabolism , Seedlings/metabolism , Seedlings/drug effects , Seedlings/growth & development , Seedlings/genetics , Seeds/drug effects , Seeds/metabolism , Seeds/growth & development , Seeds/genetics , Stress, Physiological , Crops, Agricultural/metabolism , Crops, Agricultural/growth & development , Crops, Agricultural/genetics , Gene Expression Regulation, Plant/drug effects
19.
Article in English | MEDLINE | ID: mdl-39230847

ABSTRACT

Establishing new medical schools in medically under-served regions is suggested as part of the solution to the problem of doctor shortages and maldistributions. Establishing a new medical school is, however, a complex undertaking with high financial and political stakes. Critically, the evidence-base for this significant activity has not previously been elucidated. This paper presents the first scoping review on this vitally important, yet under-researched aspect of medical education and health workforce planning. To better understand the process of new medical school establishment, this review posed two research questions: (1) What is the nature of the available literature on establishing a new medical school?; (2) What are the key factors to be considered when establishing a new medical school? Five databases and grey literature were searched in 2015 and 2021 for English-language articles, using search terms related to new medical schools and their establishment. Inclusion and exclusion criteria were based on relevance and suitability in answering the research questions. Seventy-eight articles were analysed both structurally and thematically to understand the nature of the literature and the key considerations involved. Structurally, most articles were descriptive pieces outlining personal and institutional experiences and did not make use of research methodologies nor theory. Thematically, thirteen key considerations were identified including reasons for establishment; location choices; leadership and governance; costs and funding; partnerships; staffing; student numbers; student recruitment; curriculum design and implementation; clinical training sites; buildings and facilities; information and technology resources; and accreditation. Significant gaps in the literature included how to obtain the initial permission from governing authorities and the personal costs and burnout experienced by founding leaders and staff. Although, the literature on new medical school establishment is empirically and theoretically under-developed, it is still useful and reveals a number of important considerations that could assist founding leaders and teams to maximise the outcomes and impact of their establishment efforts. Critically, the evidence-base underpinning this complex undertaking needs to be better informed by theory and research.

20.
BMC Public Health ; 24(1): 695, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38438874

ABSTRACT

BACKGROUND: Anhui Province is currently facing an increase in imported malaria cases as a result of globalization and international travel. In response, Anhui Province has implemented a comprehensive adaptive framework to effectively address this threat. METHODS: This study collected surveillance data from 2012 to 2022 in Anhui Province. Descriptive statistics were used to analyze the epidemiological characteristics of imported malaria cases. Additionally, multivariate logistic regression was employed to identify factors associated with severe malaria. Documents were reviewed to document the evolution of the adaptive framework designed to combat imported malaria. The effectiveness of the adaptive framework was evaluated based on the rates of timely medical visits, timely diagnosis, and species identification. RESULTS: During the study period, a total of 1008 imported malaria cases were reported across 77 out of 105 counties in Anhui Province, representing a coverage of 73.33%. It was found that 10.52% of imported cases went undiagnosed for more than seven days after onset. The multivariate analysis revealed several potential risk factors for severe malaria, including increasing age (OR = 1.049, 95%CI:1.015-1.083), occupation (waitperson vs. worker, OR = 2.698, 95%CI:1.054-6.906), a longer time interval between onset and the initial medical visit (OR = 1.061, 95%CI:1.011-1.114), and misdiagnosis during the first medical visit (OR = 5.167, 95%CI:2.535-10.533). Following the implementation of the adaptive framework, the rates of timely medical visits, timely diagnosis, and species identification reached 100.00%, 78.57%, and 100.00%, respectively. CONCLUSIONS: Anhui Province has successfully developed and implemented an adaptive framework for addressing imported malaria, focusing on robust surveillance, prompt diagnosis, and standardized treatment. The experiences gained from this initiative can serve as a valuable reference for other non-endemic areas.


Subject(s)
Malaria , Humans , Malaria/diagnosis , Malaria/epidemiology , China/epidemiology , Risk Factors , Multivariate Analysis
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