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1.
Dev Biol ; 511: 84-91, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38648924

RESUMO

We established a normal embryonic development table for the Anji salamander Hynobius amjiensis, a critically endangered tailed amphibian of the family Hynobiidae with a very limited distribution in East China, following the standards set by the early developmental table of vertebrates. Put together 32 embryonic stages for the Anji salamander was defined. The total embryonic period from oviposition to hatching is approximately 30 days at 9 °C. Stages 1-16 represent early development from cleavage to neurulation. Stages 17-32 represent organogenesis documenting later developmental events such as tail, gill, and limb formation, and hatching (Stage 32). We provided a detailed description of the external morphology and color changes of the head, trunk, limbs, tail, external gills, and balancers at various stages from egg-laying to hatching. We also described several cases of abnormal embryonic development. The establishment of the embryonic development table in H. amjiensis contributes to better understanding of the ontogeny in tailed amphibians, distinguishing closely related species, and identifying abnormal embryonic amphibians.

2.
J Autism Dev Disord ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607472

RESUMO

OBJECTIVES: Two studies were conducted to better understand how children with intellectual disabilities (ID) empathize with the feelings of others during social interactions. The first study tested hypotheses of developmental delay or difference regarding empathy in 79 children with ID by comparing them with typically developing (TD) children, matched for developmental age or chronological age. The second study examined specific aspects of empathy in 23 children with Down syndrome (DS), compared with 23 nonspecific ID children, matched for developmental age, and TD children, matched for developmental age or chronological age. METHOD: An empathy task was administered to the children while their parents completed the French versions of the Empathy Questionnaire and the Griffith Empathy Measure. RESULTS: The first study showed that ID children showed delayed empathy development but were perceived by their parents as deficient in cognitive empathy. The second study showed that DS children were perceived as being more attentive to the feelings of others than TD children and non-specific ID children, matched for developmental age, and as having affective empathy that was similar to that of TD children matched for chronological age. CONCLUSION: These studies have drawn attention to delays or differences in different dimensions of empathy in children with ID and DS, which need to be taken into account in interventions.

3.
Arch Sex Behav ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448690

RESUMO

Two components of gender identity are gender similarity, how one's self-concept relates to the major gender collectives (i.e., female, male), and felt pressure to conform to gender norms. The development of these components across ages and contexts has been understudied. The focus of this study was to examine variations in gender similarity and felt pressure across multiple intersecting contexts: developmental stage, gender, and ethnic-racial group. Six data sets were harmonized and means were compared across 2628 participants (51% girls, 49% boys) from four different developmental cohorts (childhood n = 678, early adolescence n = 1322, adolescence n = 415, and young adulthood n = 213) from diverse ethnic-racial backgrounds (45% White, 23% Latinx/Hispanic, 11% Black/African-American, 7% Asian-American, 5% American Indian, and 5% Multiracial). Results revealed nuanced patterns: Gender intensification was supported in early adolescence, primarily for boys. Young adult men reported lower levels of pressure and gender typicality than younger boys, but young adult women's levels were generally not different than younger girls. Surprisingly, young adult women's levels of own-gender similarity and pressure from parents were higher than adolescent girls. Expectations of gender differences in gender typicality and felt pressure were supported for all ages except young adults, with higher levels for boys. Finally, there were more similarities than differences across ethnic-racial groups, though when there were differences, minoritized participants reported heightened gender typicality and pressure (largely accounted for by higher scores for Black and Latinx participants and lower scores for White and Multiracial participants). These results add to what is understood about contextually dependent gender development.

4.
Genes Genomics ; 46(5): 601-611, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38546934

RESUMO

Human advancements in agriculture, urbanization, and industrialization have led to various forms of environmental pollution, including heavy metal pollution. Insects, as highly adaptable organisms, can survive under various environmental stresses, which induce oxidative damage and impair antioxidant systems. To investigate the peroxidase (POX) family in Tenebrio molitor, we characterized two POXs, namely TmPOX-iso1 and TmPOX-iso2. The full-length cDNA sequences of TmPox-iso1 and TmPox-iso2 respectively consisted of an open reading frame of 1815 bp encoding 605 amino acids and an open reading frame of 2229 bp encoding 743 amino acids. TmPOX-iso1 and TmPOX-iso2 homologs were found in five distinct insect orders. In the phylogenetic tree analysis, TmPOX-iso1 was clustered with the predicted POX protein of T. castaneum, and TmPOX-iso2 was clustered with the POX precursor protein of T. castaneum. During development, the highest expression level of TmPox-iso1 was observed in the pre-pupal stage, while that of TmPox-iso2 expression were observed in the pre-pupal and 4-day pupal stages. TmPox-iso1 was primarily expressed in the early and late larval gut, while TmPox-iso2 mRNA expression was higher in the fat bodies and Malpighian tubules. In response to cadmium chloride treatment, TmPox-iso1 expression increased at 3 hours and then declined until 24 hours, while in the zinc chloride-treated group, TmPox-iso1 expression peaked 24 hours after the treatment. Both treated groups showed increases in TmPox-iso2 expression 24 hours after the treatments.


Assuntos
Tenebrio , Animais , Humanos , Tenebrio/genética , Peroxidases/genética , Filogenia , Proteínas/genética , Aminoácidos/genética
5.
Nutrients ; 16(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542757

RESUMO

The occurrence of overweight and obesity among individuals with Autism Spectrum Disorder (ASD) has become a worldwide epidemic. However, there is limited research on this topic in the Lebanese population. Therefore, this study aimed to assess the differences in anthropometric measurements and body composition variables among Lebanese children, pre-adolescents, and adolescents diagnosed with ASD in contrast to typically developing peers across various developmental stages. Additionally, it aimed to investigate the prevalence of overweight and obesity within this population. A total of 86 participants with ASD and 86 controls were involved in this case-control study, conducted between June 2022 and June 2023. Anthropometric measurements and body composition variables were assessed, followed by statistical analyses to examine the differences between these two groups. The results revealed a significantly higher prevalence of overweight and obesity among individuals with ASD, particularly evident during childhood and pre-adolescence. Additionally, this group exhibited a higher body fat mass and total body fat percentage compared to controls. However, there were no significant differences observed between the two groups during adolescence. These findings emphasize the significance of monitoring and addressing weight status in individuals with ASD to improve their overall health outcomes. Future research directions could focus on investigating the underlying mechanisms contributing to the heightened prevalence of overweight and obesity in this population, ultimately enhancing their quality of life and well-being.


Assuntos
Transtorno do Espectro Autista , Criança , Humanos , Adolescente , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/diagnóstico , Sobrepeso/epidemiologia , Estudos de Casos e Controles , Líbano/epidemiologia , Qualidade de Vida , Obesidade/epidemiologia , Composição Corporal
7.
Front Vet Sci ; 11: 1367730, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440388

RESUMO

Spermatogenesis is a complex process intricately regulated by the hypothalamic-pituitary-testis (HPT) axis. However, research on the regulatory factors governing the HPT axis remains limited. This study addresses this gap by conducting a comprehensive analysis of transcriptomes from the pituitary and testis tissues across various developmental stages, encompassing embryonic day (E120), neonatal period (P0), pre-puberty (P90), and post-puberty day (P270). Utilizing edgeR and WGCNA, we identified stage-specific genes in both the pituitary and testis throughout the four developmental stages. Notably, 380, 242, 34, and 479 stage-specific genes were identified in the pituitary, while 886, 297, 201, and 3,678 genes were identified in the testis. Subsequent analyses unveiled associations between these stage-specific genes and crucial pathways such as the cAMP signaling pathway, GnRH secretion, and male gamete generation. Furthermore, leveraging single-cell data from the pituitary and testis, we identified some signaling pathways involving BMP, HGF, IGF, and TGF-ß, highlighting mutual regulation between the pituitary and testis at different developmental stages. This study sheds light on the pivotal role of the pituitary-testis axis in the reproductive process of sheep across four distinct developmental stages. Additionally, it delves into the intricate regulatory networks governing reproduction, offering novel insights into the dynamics of the pituitary-testis axis within the reproductive system.

8.
Appl Microbiol Biotechnol ; 108(1): 225, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376561

RESUMO

The gut microbial communities interact with the host immunity and physiological functions. In this study, we investigated the bacterial composition in Litopenaeus vannamei shrimp's gut and rearing water under different host (developmental stage: juvenile and adult; health status: healthy and diseased) and environmental factors (temperature 25 °C and 28 °C; and light intensity: low and high). The PCoA analysis showed that all water samples were clustered together in a quarter, whereas the gut samples spread among three quarters. In terms of functional bacteria, gut samples of adult shrimp, healthy adult shrimp, adult shrimp raised at 28 °C, and juvenile shrimp under high light intensity exhibited a higher abundance of Vibrionaceae compared to each other opposite group. Gut samples of juvenile shrimp, infected adult shrimp, juvenile shrimp with low light intensity, and adult shrimp with a water temperature of 25 °C showed a higher abundance of Pseudoaltromonadaceae bacteria compared to each other opposite group. Gut samples of juvenile shrimp, healthy adult shrimp, adult shrimp raised at a water temperature of 28 °C, and juvenile shrimp with high light intensity showed the higher abundance of Firmicutes/Bacteroidota ratio compared to each other opposite group. Our results showed that L. vannamei juveniles are more sensitive to bacterial infections; besides, water temperature of 28 °C and high light intensity groups were both important conditions improving the shrimp gut bacterial composition under industrial indoor farming systems. KEY POINTS: • Bacteria diversity was higher among shrimp intestinal microbiota compared to the rearing water. • Shrimp juveniles are more sensitive to bacterial infection compared to adults. • Water temperature of 28 °C and high light intensity are recommended conditions for white shrimp aquaculture.


Assuntos
Microbioma Gastrointestinal , Microbiota , Penaeidae , Animais , Agricultura , Fazendas , Água
9.
Food Chem ; 442: 138432, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241991

RESUMO

The fruit of Lycium barbarum (Lb), known as red goji berry, is a "superfruit" due to its abundance of bioactive compounds. Among these compounds, dicaffeoylspermidine derivatives (DCSPDs) have anti-oxidant and anti-Alzheimer's Disease activity. This study employed ultra-high-performance liquid chromatography with tandem mass spectrometry to investigate metabolic changes during the development and ripening stages of red goji berries. Totally 97 compounds, including 51 DCSPDs, were tentatively identified. Correlation analysis of these DCSPDs revealed that glycosyltransferases (GTs) play an important role in the formation of glycosylated DCSPDs. In vitro experiments characterized 3 novel GTs could add a glucosyl moiety to N1-caffeoyl-N10-dihydrocaffeoyl spermidine. Homologous GTs from L. ruthenicum (Lr) exhibited similar activity, despite the absence of abundant glycosylated DCSPDs in Lr. These findings provide insights into the metabolic changes and interconnections among active compounds in red goji berries. The identified GTs hold potential for metabolic engineering of DCSPDs and functional food development.


Assuntos
Lycium , Lycium/química , Frutas/química , Glucosiltransferases/metabolismo , Espectrometria de Massas em Tandem , Antioxidantes/química
10.
J Environ Manage ; 353: 120215, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38281422

RESUMO

Tidal channel networks, which characterize all river deltas, control the exchange of water and nutrients (hydrological connectivity) between the ocean and the delta area. Therefore, a tidal channel network in optimal conditions ensures the maintenance of the diversity and stability of the deltaic ecosystem. However, the developmental status of channel networks in the Yellow River Delta, China, has not been clearly determined. Here, we selected a typical tidal channel network in this delta that showed different spatial patterns (e.g., connectivity attributes) in the past three decades and explored its evolution using entropy as an index of connectivity. Seven scenarios were set up to determine the optimal status of the tidal channel network by optimizing its structure. The optimization effect was evaluated by comparing the connectivity attributes of the channel network before and after optimization. The results showed that the network experienced two obviously different developmental phases: an evolution before 2005 and a regression after 2005. Mann-Kendall analysis indicated that the channel network achieved dynamic stability before 2014 and became unstable thereafter. The simulations conducted to optimize the system showed that adding outlets changed the current patterns of the network' structural and functional connectivity. As the optimization proceeded, structural connectivity increased while functional connectivity decreased, and the tidal channel network tended to be dynamically stable. Our study elucidated the quantitative relationship between outlet number and stability within tidal channel networks, providing reference information that could be incorporated into future projects for the restoration and management of river deltas.


Assuntos
Ecossistema , Rios , Rios/química , China , Hidrologia
11.
Bull Entomol Res ; 114(1): 57-66, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38180086

RESUMO

The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is a major destructive insect pest of coffee, which impacts the coffee crops negatively. As a draft genome has been completed for this insect, most molecular studies on gene transcriptional levels under different experimental conditions will be conducted using real-time reverse-transcription quantitative polymerase chain reactions (RT-qPCR). However, the lack of suitable internal reference genes will affect the accuracy of RT-qPCR results. In this study, the expression stability of nine candidate reference genes was evaluated under different developmental stages, temperature stress, and Beauveria bassiana infection. Data analyses were completed by four commonly used programs, BestKeeper, NormFinder, geNorm, and RefFinder. The result showed that RPL3 and EF1α combination were recommended as the most stable reference genes for developmental stages. EF1α and RPS3a combination were the top two stable reference genes for B. bassiana infection. RPS3a and RPL3 combination performed as the optimal reference genes both in temperature stress and all samples. Our results should provide a good foundation for the expression profile analyses of target genes in the future, especially for molecular studies on insect genetic development, temperature adaptability, and immune mechanism to entomogenous fungi in H. hampei.


Assuntos
Beauveria , Coffea , Besouros , Gorgulhos , Animais , Coffea/genética , Temperatura
12.
MethodsX ; 12: 102526, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38192358

RESUMO

Fish display diverse reproductive strategies and their gametogenesis is influenced by numerous genetic, physiological and environmental factors. The analysis of 5S rRNA expression levels in gonads has been proposed as useful method for the molecular identification of the presence of oocytes in fish tissues. The present method provides an easy and unbiased approach to analyse the expression of tRNAs and 5S rRNA in teleost gonads and stablish the presence and developmental stage of oocytes. Total RNA extracted from gonads is analysed through capillary electrophoresis in a Bioanalyzer 2100 (Agilent Technologies) using Small RNA Assays. Electropherograms allow quantifying the concentrations of tRNAs, 5S rRNA and 5.8S rRNA per sample and calculate their tRNA/5.8S rRNA and 5S/5.8S rRNA indices. Both indices clearly differentiate ovaries from testes and can be used to identify testes that present oocytes due to exposure to environmental xenoestrogens. The tRNA/5.8S and 5S/5.8S indices show the highest values in ovaries in previtellogenic stage, values decreasing as they advance towards maturity.•Detailed molecular method to sex fish and quantitatively identify the maturity stage of females.•tRNA levels in gonads can help in the study of teleost reproduction (female fecundity assessment, molecular gonad sexing) and environmental health assessment.

13.
Neuroimage ; 285: 120493, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38086496

RESUMO

Early-onset Schizophrenia (EOS) is a profoundly progressive psychiatric disorder characterized by both positive and negative symptoms, whose pathogenesis is influenced by genes, environment and brain structure development. In this study, the MIND (Morphometric Inverse Divergence) network was employed to explore the relationship between morphological similarity and specific transcriptional expression patterns in EOS patients. This study involved a cohort of 187 participants aged between 7 and 17 years, consisting of 97 EOS patients and 90 healthy controls (HC). Multiple morphological features were used to construct the MIND network for all participants. Furthermore, we explored the associations between MIND network and brain-wide gene expression in EOS patients through partial least squares (PLS) regression, shared genetic predispositions with other psychiatric disorders, functional enrichment of PLS weighted genes, as well as transcriptional signature assessment of cell types, cortical layers, and developmental stages. The MIND showed similarity differences in the orbitofrontal cortex, pericalcarine cortex, lingual gyrus, and multiple networks in EOS patients compared to HC. Moreover, our exploration revealed a significant overlap of PLS2 weighted genes linking to EOS-related MIND differences and the dysregulated genes reported in other psychiatric diseases. Interestingly, genes correlated with MIND changes (PLS2-) exhibited a significant enrichment not only in metabolism-related pathways, but also in specific astrocytes, cortical layers (specifically layer I and III), and posterior developmental stages (late infancy to young adulthood stages). However, PLS2+ genes were primarily enriched in synapses signaling-related pathways and early developmental stages (from early-mid fetal to neonatal early infancy) but not in special cell types or layers. These findings provide a novel perspective on the intricate relationship between macroscopic morphometric structural abnormalities and microscopic transcriptional patterns during the onset and progression of EOS.


Assuntos
Esquizofrenia , Recém-Nascido , Humanos , Adulto Jovem , Adulto , Criança , Adolescente , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Imageamento por Ressonância Magnética , Encéfalo , Córtex Pré-Frontal , Lobo Occipital
14.
Zool Res ; 45(1): 55-68, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38114433

RESUMO

The gastrointestinal tract is essential for food digestion, nutrient absorption, waste elimination, and microbial defense. Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity, functional heterogeneity, and their importance in intestinal tract development and disease. Although such profiling has been extensively conducted in humans and mice, the single-cell gene expression landscape of the pig cecum remains unexplored. Here, single-cell RNA sequencing was performed on 45 572 cells obtained from seven cecal samples in pigs at four different developmental stages (days (D) 30, 42, 150, and 730). Analysis revealed 12 major cell types and 38 subtypes, as well as their distinctive genes, transcription factors, and regulons, many of which were conserved in humans. An increase in the relative proportions of CD8 + T and Granzyme A (low expression) natural killer T cells (GZMA low NKT) cells and a decrease in the relative proportions of epithelial stem cells, Tregs, RHEX + T cells, and plasmacytoid dendritic cells (pDCs) were noted across the developmental stages. Moreover, the post-weaning period exhibited an up-regulation in mitochondrial genes, COX2 and ND2, as well as genes involved in immune activation in multiple cell types. Cell-cell crosstalk analysis indicated that IBP6 + fibroblasts were the main signal senders at D30, whereas IBP6 - fibroblasts assumed this role at the other stages. NKT cells established interactions with epithelial cells and IBP6 + fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs. This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages.


Assuntos
Ceco , Intestinos , Humanos , Camundongos , Animais , Suínos , Ceco/metabolismo , Trato Gastrointestinal , Perfilação da Expressão Gênica/veterinária , Células Epiteliais
15.
Microorganisms ; 11(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38138050

RESUMO

Trypanosoma dionisii, for which only bat bugs (Cimicidae) had previously been demonstrated as vectors, was, for the first time, detected in the gamasine mite Steatonyssus periblepharus in Russia. The molecular phylogenetic analysis indicated that trypanosomes found in these mites belong to the "clade A" of T. dionisii, which, based on genetic distances, can be considered as a species separate from the sister clade B, and according to available data also has a distinct geographic distribution. The presence of developmental forms of T. dionisii resembling those previously described during the development of this trypanosome in cimicids suggests that S. periblepharus is a novel vector of the studied trypanosome.

16.
Sheng Wu Gong Cheng Xue Bao ; 39(12): 4996-5013, 2023 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-38147997

RESUMO

Transmembrane emp24 domain (TMED) gene is closely related to immune response, signal transduction, growth and disease development in mammals. However, only the Drosophila TMED gene has been reported on insects. We identified the TMED family genes of silkworm, Tribolium castaneum, tobacco moth and Italian bee from their genomes, and found that the TMED family gene composition patterns of one α-class, one ß-class, one δ-class and several γ-classes arose in the common ancestor of pre-divergent Hymenoptera insects, while the composition of Drosophila TMED family members has evolved in a unique pattern. Insect TMED family γ-class genes have evolved rapidly, diverging into three separate subclasses, TMED6-like, TMED5-like and TMED3-like. The TMED5-like gene was lost in Hymenoptera, duplicated in the ancestors of Lepidoptera and duplicated in Drosophila. Insect TMED protein not only has typical structural characteristics of TMED, but also has obvious signal peptide. There are seven TMED genes in silkworm, distributed in six chromosomes. One of seven is single exon and others are multi-exons. The complete open reading frame (ORF) sequences of seven TMED genes of silkworm were cloned from larval tissues and registered in GenBank database. BmTMED1, BmTMED2 and BmTMED6 were expressed in all stages and tissues of the silkworm, and all genes were expressed in the 4th and 5th instar and silk gland of the silkworm. The present study revealed the composition pattern of TMED family members, their γ class differentiation and their evolutionary history, providing a basis for further studies on TMED genes in silkworm and other insects.


Assuntos
Bombyx , Mariposas , Animais , Bombyx/genética , Bombyx/metabolismo , Genes de Insetos/genética , Mariposas/genética , Mariposas/metabolismo , Insetos/genética , Insetos/metabolismo , Drosophila , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Filogenia , Mamíferos/genética
17.
Animals (Basel) ; 13(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37958107

RESUMO

Diploid and triploid Atlantic salmon show distinct physiological differences including heart, brain, and digestive system morphology, propensity for certain deformities, temperature tolerance as eggs and once hatched, and different nutritional requirements. Whilst several studies have looked in detail at the rate of embryogenesis in diploid salmon, no study has compared the rate of embryogenesis between ploidies from fertilisation to hatch. This study based its assessment on a seminal paper by Gorodilov (1996) and used the same techniques to compare the rate at which triploid and diploid embryos developed morphological characteristics. Whilst no significant difference was found, this study provides well-needed justification for the assumption that both ploidies develop at the same rate and gives scientific weight to studies which involve manipulation at these stages of development. Two factors that did differ, however, were the timing of hatch, and mortality. Triploids hatched more quickly than diploids and reached 50% hatch at a significantly earlier point. Triploids also suffered from a significantly higher rate of mortality.

18.
Bioinformation ; 19(10): 987-989, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37969664

RESUMO

Early childhood is the timely and critical period in the growth of the human being when the trajectory of children's holistic development is traced, and the foundation for their future as well-established and productive adults is set. The CoViD-19 pandemic produced profound changes in everyday life almost everywhere in the world. The personal, social and societal restrictions imposed during the CoViD-19 pandemic unquestionably blunted early childhood development by depriving young children from normal and healthy attachments through secure relationships with parents, teachers and peers. Furthermore, the public health measures enacted to counter the spread of the pandemic (e.g., mandatory masking, lockdown) contributed to a lack of social interactions essential for childhood development, and provoked perceptions of psycho-emotional stress (e.g., objective fear of the masked interlocutor, perceived fear of abandonment) in the children, which may have hampered critical periods of development. Based on theoretical foundation and our observations in the field, we propose that early intervention support may have a significant impact on the development of children victims of the effect of the CoViD-19 pandemic.

19.
Global Health ; 19(1): 90, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996877

RESUMO

INTRODUCTION: Pooled procurement can be seen as a collaboration initiative of buyers. Such mechanisms have received increased attention during the Covid-19 pandemic to improve access to affordable and quality-assured health commodities. The structural form of pooled procurement mechanisms ranges from a third-party organization that procures on behalf of its buyers to a buyer's owned mechanism in which buyers operate more collaboratively. However, little is known about how these types of pooled procurement mechanisms differ in terms of characteristics, implementation and developmental process. To fill this gap, we compared four pooled procurement mechanisms. Two buyer's owned mechanisms: the Organisation of the Eastern Caribbean States (OECS) and the Pacific Island Countries (PIC). And two third-party mechanisms: the Global Drug Facility (GDF) and the Asthma Drug Facility (ADF). METHODS: For this qualitative study, we used a multiple case-study design. The cases were purposefully selected, based on a most-similar case study design. We used the Pooled Procurement Guidance to collect data on individual cases and compared our findings between the case studies. For our analysis, we drew upon peer-reviewed academic articles, grey literature documents and 9 semi-structured interviews with procurement experts. RESULTS: Buyers within a buyer's owned mechanisms differ in procurement systems, financing structures, product needs and regulatory and legal frameworks. Therefore, buyers within such mechanisms require relative alignment on motivations, goals and operations of the mechanism. Our study showed that buyers' relative homogeneity of characteristics and their perceived urgency of the problems was particularly relevant for achieving that alignment. Third-party organization mechanisms require less alignment and consensus-building between buyers. To participate, buyers need to align with the operations of the third-party organization, instead of other buyers. Elements that were essential for the successful implementation and operation of such mechanisms included the procurement secretariat's ability to create local and global awareness around the problem, to induce political will to act upon the problem, to mobilize sufficient funding and to attract qualified staff. CONCLUSION: To successfully sustain pooled procurement mechanisms over time, key actors should drive the mechanism through continuous and reflexive work on stakeholder engagement, mobilization of funding and alignment of interests and needs.


Assuntos
Organizações , Pandemias , Humanos , Região do Caribe , Ilhas do Pacífico
20.
Environ Sci Pollut Res Int ; 30(56): 118724-118735, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37917265

RESUMO

The pattern of arsenic (As) uptake at different developmental stages in plants and its consequent influence on the growth of plants was investigated in bean and lettuce. Further, the human health risk from the consumption of these As-laced vegetables was determined. The irrigation water was contaminated with As at concentrations of 0.1, 0.25, and 0.5 mg/L. The As concentration in the plant parts (root, stem, leaves, and flower/fruit) was determined in bean at the young, flowering, and fruiting stages and lettuce at the young and mature stages. At the different growth stages, As had an impact on the biomass of bean and lettuce plant parts, but none of the biomass changes were significant (p>0.05). The increase in As concentration of the irrigation water elevated the As concentration of plant parts of both plants at all growth stages, with the exception of the bean fruit. The As concentration in the developmental stages was in the order: lettuce (young>mature) and bean (fruiting>young>flowering). In lettuce, the transfer factor was higher at the young stage (0.09-0.19, in the control and 0.1 mg/L As treatment), while in bean, it was highest at the flowering stage (0.09-0.41, in all treatments). In the edible part, lettuce possessed substantially elevated As concentrations (0.30, 0.61, and 1.21 mg/kg DW) compared to bean (0.008, 0.005, and 0.022 mg/kg DW) at As treatments of 0.1, 0.25, and 0.5 mg/L, respectively, and posed significant health risks at all applied As concentrations.


Assuntos
Arsênio , Humanos , Verduras , Folhas de Planta , Água
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