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1.
Pain ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39073407

RESUMEN

ABSTRACT: Microglia take on an altered morphology during chronic opioid treatment. This morphological change is broadly used to identify the activated microglial state associated with opioid side effects, including tolerance and opioid-induced hyperalgesia (OIH). Microglia display similar morphological responses in the spinal cord after peripheral nerve injury (PNI). Consistent with this observation, functional studies have suggested that microglia activated by opioids or PNI engage common molecular mechanisms to induce hypersensitivity. In this article, we conducted deep RNA sequencing (RNA-seq) and morphological analysis of spinal cord microglia in male mice to comprehensively interrogate transcriptional states and mechanistic commonality between multiple models of OIH and PNI. After PNI, we identify an early proliferative transcriptional event across models that precedes the upregulation of histological markers of microglial activation. However, we found no proliferative transcriptional response associated with opioid-induced microglial activation, consistent with histological data, indicating that the number of microglia remains stable during morphine treatment, whereas their morphological response differs from PNI models. Collectively, these results establish the diversity of pain-associated microglial transcriptomic responses and point towards the targeting of distinct insult-specific microglial responses to treat OIH, PNI, or other central nervous system pathologies.

2.
Proc Natl Acad Sci U S A ; 121(30): e2408109121, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39028694

RESUMEN

The prevalence of "long COVID" is just one of the conundrums highlighting how little we know about the lung's response to viral infection, particularly to syndromecoronavirus-2 (SARS-CoV-2), for which the lung is the point of entry. We used an in vitro human lung system to enable a prospective, unbiased, sequential single-cell level analysis of pulmonary cell responses to infection by multiple SARS-CoV-2 strains. Starting with human induced pluripotent stem cells and emulating lung organogenesis, we generated and infected three-dimensional, multi-cell-type-containing lung organoids (LOs) and gained several unexpected insights. First, SARS-CoV-2 tropism is much broader than previously believed: Many lung cell types are infectable, if not through a canonical receptor-mediated route (e.g., via Angiotensin-converting encyme 2(ACE2)) then via a noncanonical "backdoor" route (via macropinocytosis, a form of endocytosis). Food and Drug Administration (FDA)-approved endocytosis blockers can abrogate such entry, suggesting adjunctive therapies. Regardless of the route of entry, the virus triggers a lung-autonomous, pulmonary epithelial cell-intrinsic, innate immune response involving interferons and cytokine/chemokine production in the absence of hematopoietic derivatives. The virus can spread rapidly throughout human LOs resulting in mitochondrial apoptosis mediated by the prosurvival protein Bcl-xL. This host cytopathic response to the virus may help explain persistent inflammatory signatures in a dysfunctional pulmonary environment of long COVID. The host response to the virus is, in significant part, dependent on pulmonary Surfactant Protein-B, which plays an unanticipated role in signal transduction, viral resistance, dampening of systemic inflammatory cytokine production, and minimizing apoptosis. Exogenous surfactant, in fact, can be broadly therapeutic.


Asunto(s)
COVID-19 , Pulmón , Organoides , SARS-CoV-2 , Internalización del Virus , Humanos , SARS-CoV-2/fisiología , SARS-CoV-2/inmunología , COVID-19/inmunología , COVID-19/virología , Pulmón/virología , Pulmón/inmunología , Pulmón/patología , Organoides/virología , Tratamiento Farmacológico de COVID-19 , Células Madre Pluripotentes Inducidas/virología , Enzima Convertidora de Angiotensina 2/metabolismo , Inflamación , Citocinas/metabolismo , Apoptosis
3.
Am Psychol ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052356

RESUMEN

Self-determination theory's (SDT) dual process model claims that parental autonomy support relates positively to child well-being, while psychologically controlling parenting is linked positively to child ill-being. We tested these claims using a combination of one-stage and univariate meta-analytic structural equation modeling with moderation (k = 238; n = 1,040, N = 126,423). In the univariate models, parental autonomy support was linked positively with child well-being, r = 0.30, 95% CI [0.26, 0.33], whereas parental psychological control was positively linked with child ill-being, r = 0.26, 95% CI [0.23, 0.28]. Consistent with SDT's dual process model, the one-stage model that controlled for the intercorrelations between predictors showed that parental autonomy support and psychological control had distinct links to child wellness outcomes. Parental autonomy support was linked positively with child well-being, even when accounting for psychological control, r = 0.26, 95% CI [0.20, 0.31], and parental psychological control was positively linked to child ill-being, controlling for autonomy support, r = 0.20, 95% CI [0.17, 0.23]. Crucially, the beneficial effects of parental autonomy support and the costs of psychological control applied across regions, degrees of national individualism and cultural hierarchy, as well as child developmental periods and sexes. These results help move the field beyond debates about whether autonomy is beneficial toward questions about manifestations of autonomy across groups and variations in its optimal support. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

4.
Open Forum Infect Dis ; 11(6): ofae072, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38887482

RESUMEN

Invasive candidiasis is a rising global health threat with increasing incidence, persistently high mortality, and diminishing treatment options. Antifungal resistance has rapidly emerged and spread, with multidrug-resistant species deemed an urgent and serious threat. While acknowledging the key role of antifungal stewardship and infection control in curbing spread, we examine the role of antifungal monotherapy in driving resistance and the potential for combination therapy to prevent stress adaptation and emergence of drug resistance. In addition to its role in mitigating resistance, combination treatment may improve drug penetration, expedite fungal clearance, and allow lower, less toxic doses of individual drugs to be used. A growing body of laboratory-based evidence suggests that antifungal combinations can yield synergistic activity against Candida spp., including against frequently multidrug-resistant Candida auris. It is imperative to test these combinations in clinical trials, incorporating resistance end points as a marker of success.

5.
Proc Natl Acad Sci U S A ; 121(24): e2321267121, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38838014

RESUMEN

Mitochondria perform an array of functions, many of which involve interactions with gene products encoded by the nucleus. These mitochondrial functions, particularly those involving energy production, can be expected to differ between sexes and across ages. Here, we measured mitochondrial effects on sex- and age-specific gene expression in parental and reciprocal F1 hybrids between allopatric populations of Tigriopus californicus with over 20% mitochondrial DNA divergence. Because the species lacks sex chromosomes, sex-biased mitochondrial effects are not confounded by the effects of sex chromosomes. Results revealed pervasive sex differences in mitochondrial effects, including effects on energetics and aging involving nuclear interactions throughout the genome. Using single-individual RNA sequencing, sex differences were found to explain more than 80% of the variance in gene expression. Males had higher expression of mitochondrial genes and mitochondrially targeted proteins (MTPs) involved in oxidative phosphorylation (OXPHOS), while females had elevated expression of non-OXPHOS MTPs, indicating strongly sex-dimorphic energy metabolism at the whole organism level. Comparison of reciprocal F1 hybrids allowed insights into the nature of mito-nuclear interactions, showing both mitochondrial effects on nuclear expression, and nuclear effects on mitochondrial expression. While based on a small set of crosses, sex-specific increases in mitochondrial expression with age were associated with longer life. Network analyses identified nuclear components of strong mito-nuclear interactions and found them to be sexually dimorphic. These results highlight the profound impact of mitochondria and mito-nuclear interactions on sex- and age-specific gene expression.


Asunto(s)
Mitocondrias , Cromosomas Sexuales , Animales , Femenino , Masculino , Mitocondrias/genética , Mitocondrias/metabolismo , Cromosomas Sexuales/genética , Envejecimiento/genética , Envejecimiento/metabolismo , Fosforilación Oxidativa , Caracteres Sexuales , ADN Mitocondrial/genética , Núcleo Celular/metabolismo , Núcleo Celular/genética , Regulación de la Expresión Génica , Metabolismo Energético/genética
6.
BMC Psychol ; 12(1): 351, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879510

RESUMEN

BACKGROUND: The literature for assessing online and offline shopping behaviours that are linked to intelligent robotic goods and services is inadequate. In this study, we applied the Theory of Planned Behaviour model for guidance regarding how consumer behaviour affects their purchase intentions for intelligent robotic goods and services. METHODS: Data from 408 respondents were gathered through an online questionnaire binned into Online and Overall Shoppers, and analysed using SPSS, AMOS, and Covariance-Based Structural Equation Modelling software to evaluate the appropriateness of the measurements and to confirm data reliability, convergence, divergence, and validity. These tools were also used to track and test hypothesized relationships between the variables and model constructs used in this study. RESULTS AND CONCLUSIONS: The overarching outcomes from the data analyses indicated the Ease of Usage, Brand Perception, and Product Pricing variables causally impacted the TPB model constructs, namely Attitude, Subjective Norms, and Perceived Behaviour Control for the two populations tested with respect to their intention to purchase intelligent robotic goods and services. The reliability measurements for Ease of Usage, Brand Perception, and Product Pricing are discussed. The results are important for companies and future investors because opportunities to study the complex relationships that ultimately drive consumer behaviour and their intention to purchase intelligent robotic goods and services are provided.


Asunto(s)
Comportamiento del Consumidor , Intención , Teoría Psicológica , Robótica , Humanos , Comportamiento del Consumidor/estadística & datos numéricos , Masculino , Femenino , Adulto , Taiwán , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven , Teoría del Comportamiento Planificado
7.
Dent Mater ; 40(8): 1252-1258, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38876829

RESUMEN

OBJECTIVES: Quality control testing of dental materials requires a standard to enable the generation of reproducible and comparable data. Currently there are no standards for testing materials used for vital pulp therapy. The aim of this study was to develop a new standard to evaluate solubility of pulp preservation materials. METHODS: The solubility of three materials used for vital pulp therapy: Biodentine, TheraCal and Activa was evaluated using two international standards for dental materials ISO 4049:2019 (S1) and ISO 6876:2012 (S2). For both standards, a modified methodology was evaluated. This included changing the volume of the solution used (S1M, S2M), using Dulbecco's modified eagle medium (DMEM) as an alternative to water (S1D, S2D) and periodic solution change for the ISO 4049 method (S1P, S1MP). Materials were characterised before and after completion of solubility test using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. RESULTS: The test materials exhibited different solubility values depending on the methodology used. Biodentine exhibited significantly lower solubility when lower volumes of solution were used when tested using both ISO methods (p ≤ 0.05). TheraCal and Activa showed negative solubility values after desiccation when tested using ISO 4049:2019. The Biodentine exhibited changes in its microstructure which was dependent on the method used to test solubility. CONCLUSIONS: The solubility values obtained were dependent on the method used. It is thus important to use methods that replicate the clinical environment for meaningful evaluations.


Asunto(s)
Compuestos de Calcio , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Silicatos , Solubilidad , Difracción de Rayos X , Silicatos/química , Compuestos de Calcio/química , Materiales Dentales/química , Compuestos de Aluminio/química , Materiales de Recubrimiento Pulpar y Pulpectomía/química , Óxidos/química , Combinación de Medicamentos
8.
Vaccines (Basel) ; 12(6)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38932386

RESUMEN

It is important to understand real-world BNT162b2 COVID-19 vaccine effectiveness (VE), especially among racial and ethnic minority groups. We performed a test-negative case-control study to measure BNT162b2 COVID-19 VE in the prevention of COVID-19-associated acute respiratory illness (ARI) hospitalizations at two Atlanta hospitals from May 2021-January 2023 and adjusted for potential confounders by multivariate analysis. Among 5139 eligible adults with ARI, 2763 (53.8%) were enrolled, and 1571 (64.5%) were included in the BNT162b2 analysis. The median age was 58 years (IQR, 44-68), 889 (56.6%) were female, 1034 (65.8%) were African American, 359 (22.9%) were White, 56 (3.6%) were Hispanic ethnicity, 645 (41.1%) were SARS-CoV-2-positive, 412 (26.2%) were vaccinated with a primary series, and 273 (17.4%) had received ≥1 booster of BNT162b2. The overall adjusted VE of the BNT162b2 primary series was 58.5% (95% CI 46.0, 68.1), while the adjusted VE of ≥1 booster was 78.9% (95% CI 70.0, 85.1). The adjusted overall VE of primary series for African American/Black individuals was 64.0% (95% CI 49.9, 74.1) and 82.7% (95% CI 71.9, 89.4) in those who received ≥1 booster. When analysis was limited to the period of Omicron predominance, overall VE of the primary series decreased with widened confidence intervals (24.5%, 95% CI -4.5, 45.4%), while VE of ≥1 booster was maintained at 60.9% (95% CI 42.0, 73.6). BNT162b2 primary series and booster vaccination provided protection against COVID-19-associated ARI hospitalization among a predominantly African American population.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38779037

RESUMEN

Introduction: Radiotherapy (RT) stands as one of the main cancer treatments. The impact of RT and cancer treatment can have a physical and psychological impact on patients and their carers. To gain patient's trust, and ensure they feel valued, information should be provided before, during, and after RT. Patient and public involvement (PPI) has been lacking, and increased engagement with PPI groups could improve this. This rapid review aims to analyse the literature, and describe and report patient perception, experience, and satisfaction regarding the information received concerning their course of RT. Methods: To allow the synthesis of results, a pragmatic decision was made to use a rapid review approach to analyse the literature, providing more timely information to inform future work. This rapid review utilised systematic review methods and was conducted according to a pre-defined protocol including clear inclusion criteria (PROSPERO registration: CRD42023415916).Electronic databases CINAHL, AMED, Pubmed/MEDLINE, EMBASE, and PsycINFO were searched using a comprehensive search for published studies from January 2012 to November 2023. Two independent reviewers applied the eligibility criteria. Evidence from literature was extracted and transcribed into qualitative data and Braun and Clarke's six-step thematic analysis (TA) was employed to determine themes by one reviewer and checked by a second [26]. Due to the heterogeneity of the included literature, the analysis of this review is presented primarily through narrative synthesis. Results: Sixty eight articles met the inclusion criteria for this review. Emerging themes included; a desire for information based on patient characteristics, information format, patient preparedness, timing e.g. timing of information and changing priorities over time, health care professional (HCP) involvement, barriers to information, and motivators for better information delivery. Conclusions: Several factors can influence a patient's desire for information, from whom and when they receive it, to what format they would prefer to receive it. There is benefit to be gained in employing PPI and patient advocacy to inform future studies that aim to further understand the themes that emerged from this review. Such studies can therefore inform HCPs in providing patient-specific information and support by utilising multiple teaching strategies available to them.

10.
Acta Paediatr ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38808465

RESUMEN

AIM: Sudden unexpected postnatal collapse is a life-threatening event and may occur in any newborn infant. Safe skin-to-skin contact, and awareness of sudden unexpected postnatal collapse are key to its prevention. The aim of this study was to survey the presence of skin-to-skin contact and/or sudden unexpected postnatal collapse protocols in the 70 perinatal centres in the Netherlands. METHODS: We performed a survey among Dutch paediatricians to examine the safe skin-to-skin contact and sudden unexpected postnatal collapse protocols. RESULTS: We received data from 59/70 (85%) perinatal centres. At least one case of sudden unexpected postnatal collapse was reported in 35/59 (59%) of these centres. Nearly half the centres had safe skin-to-skin contact and/or sudden unexpected postnatal collapse protocols. Ultimately, 16 protocols were available for analysis. They showed considerable differences in the type of perinatal care provided. Most protocols lacked recently published insights on safe skin-to-skin contact. Besides, protocols failed to incorporate awareness of and knowledge on how to prevent sudden unexpected postnatal collapse. CONCLUSION: This study underlines the importance of drawing up uniform, multidisciplinary guidelines containing recommendations for the prevention of sudden unexpected postnatal collapse in the Netherlands.

11.
Nano Lett ; 24(22): 6813-6820, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38781191

RESUMEN

Spintronic devices incorporating magnetic skyrmions have attracted significant interest recently. Such devices traditionally focus on controlling magnetic textures in 2D thin films. However, enhanced performance of spintronic properties through the exploitation of higher dimensionalities motivates the investigation of variable-thickness skyrmion devices. We report the demonstration of a skyrmion injection mechanism that utilizes charge currents to drive skyrmions across a thickness step and, consequently, a metastability barrier. Our measurements show that under certain temperature and field conditions skyrmions can be reversibly injected from a thin region of an FeGe lamella, where they exist as an equilibrium state, into a thicker region, where they can only persist as a metastable state. This injection is achieved with a current density of 3 × 108 A m-2, nearly 3 orders of magnitude lower than required to move magnetic domain walls. This highlights the possibility to use such an element as a skyrmion source/drain within future spintronic devices.

12.
Brain Res ; 1838: 148994, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38729331

RESUMEN

PTZ kindling induces oxidative stress, neuronal cell degeneration, and neurobehavioral alterations in rodents that mimic neuropsychiatric comorbidities of epilepsy, which could be initiated or aggravated by some antiepileptic drugs. Here, we investigated the effects of the methanol extract of Ficus platyphylla (FP) on severity scores for seizures, neuronal cell degeneration, and neurobehavioral alterations in rats kindled with pentylenetetrazole (PTZ) and probed the involvement of oxidative stress in these ameliorative effects of FP. FP (50 and 100 mg/kg, p.o.) ameliorated seizure severity, neuronal cell degeneration, depressive behaviors, cognitive dysfunctions, and oxidative stress in rats kindled with PTZ (42.5 mg/kg, i.p.). The findings from this study give additional insights into the potential values of FP in the treatment of persistent epilepsy and major neuropsychiatric comorbidities via modulation of oxidative stress.


Asunto(s)
Anticonvulsivantes , Ficus , Excitación Neurológica , Estrés Oxidativo , Pentilenotetrazol , Extractos Vegetales , Convulsiones , Animales , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Excitación Neurológica/efectos de los fármacos , Masculino , Convulsiones/tratamiento farmacológico , Convulsiones/metabolismo , Convulsiones/inducido químicamente , Ratas , Anticonvulsivantes/farmacología , Ratas Wistar , Modelos Animales de Enfermedad , Conducta Animal/efectos de los fármacos , Epilepsia/tratamiento farmacológico , Epilepsia/inducido químicamente
13.
Res Sq ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38746209

RESUMEN

Our study focuses on the intricate connection between tissue-level organization and ciliated organ function in humans, particularly in understanding the morphological organization of airways and their role in mucociliary clearance. Mucociliary clearance is a key mechanical defense mechanism of human airways, and clearance failure is associated with many respiratory diseases, including chronic obstructive pulmonary disease (COPD) and asthma. While single-cell transcriptomics have unveiled the cellular complexity of the human airway epithelium, our understanding of the mechanics that link epithelial structure to clearance function mainly stem from animal models. This reliance on animal data limits crucial insights into human airway barrier function and hampers the human-relevant in vitro modeling of airway diseases. This study, for the first time, maps the distribution of ciliated and secretory cell types along the airway tree in both rats and humans, noting species-specific differences in ciliary function and elucidates structural parameters of airway epithelia that predict clearance function in both native and in vitro tissues alike. By uncovering how tissue organization influences ciliary function, we can better understand disruptions in mucociliary clearance, which could have implications for various ciliated organs beyond the airways.

14.
Ned Tijdschr Geneeskd ; 1682024 May 14.
Artículo en Holandés | MEDLINE | ID: mdl-38747614

RESUMEN

BACKGROUND: Worldwide, disease in children due to exposure to rats is increasing, also in the Netherlands. Not only the generally known pathogen Leptospira should be considered, also S. moniliformis, Yersinia pestis, Lymphocytic choriomeningitis virus, Hantavirus, Francisella tularensis and Pasteurella multocida are also known rat-associated zoonosis. CASE DESCRIPTION: An 12-year-old boy visited the pediatrician with fever, headache and nausea, followed by generalized erythema and arthritis. The boy had a pet rat. The patient's blood culture was positive for S. moniliformis. The patient was treated with antibiotics and made a full recovery. CONCLUSION: Just like many rat-associated diseases have 'rat-bite fever' caused by S. moniliformis an nonspecific clinical presentation. It is not necessary to have had a rat bite, to develop rat-bite fever. Better awareness and knowledge about rat related diseases should contribute to earlier diagnosis and treatment. Which is of great importance because of increased morbidity and mortality associated to rat related diseases.


Asunto(s)
Antibacterianos , Fiebre por Mordedura de Rata , Niño , Masculino , Humanos , Fiebre por Mordedura de Rata/diagnóstico , Fiebre por Mordedura de Rata/tratamiento farmacológico , Animales , Antibacterianos/uso terapéutico , Ratas , Resultado del Tratamiento , Streptobacillus/aislamiento & purificación , Zoonosis/diagnóstico
15.
J Evid Based Integr Med ; 29: 2515690X241251558, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38689490

RESUMEN

Liver cancer is the most common cancer among males in Africa. The disease has a poor prognosis and its treatment is associated with toxicity and resistance. For this reason, numerous herbal combinations are being subjected to anticancer screening to circumvent the shortcomings of the conventional anticancer drugs. In the current study, the in vivo anti-cancer effects of the chloroform root extract of the herb, Clausena excavata Burm were investigated. Liver cancer was induced in mice by a single intraperitoneal injection of diethylnitrosamine (DEN) followed by oral administration of the promoter of carcinogenesis, 2-aminoacetyl fluorine that was mixed with the mice feed. The cytotoxicity of the root extract of C. excavata on liver cancer cells was investigated using liver enzyme, histology, DNA fragmentation and caspases assays. Real time qPCR was conducted to evaluate the effect of the extract on apoptotic genes. The findings revealed that the extract of C. excavata significantly decreased the progression of hepatocarcinogenesis and the toxicity-induced production of the liver enzymes, alanine and aspartate aminotransferases. The histological analyses of the liver tissues revealed evidence of apoptotic cell death. The extract also provoked significant (p < .05) expressions of caspase 9 protein and gene as well as other apoptotic genes (P53, P27, Apaf-1, cytochrome C, bax and bid). Therefore, we postulate that the chloroform root extract of C. excavata induces apoptosis of liver cancer in mice.


Asunto(s)
Cloroformo , Hígado , Carcinoma Hepatocelular/inducido químicamente , Raíces de Plantas/química , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Clausena , Dietilaminas/toxicidad , Antineoplásicos Fitogénicos/farmacología
16.
Phys Rev Lett ; 132(15): 151802, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38682977

RESUMEN

We posit that the distinct patterns observed in fermion masses and mixings are due to a minimally broken U(2)_{q+e} flavor symmetry acting on left-handed quarks and right-handed charged leptons, giving rise to an accidental U(2)^{5} symmetry at the renormalizable level without imposing selection rules on the Weinberg operator. We show that the symmetry can be consistently gauged by explicit examples and comment on realizations in SU(5) unification. Via a model-independent analysis of a standard model viewed as an effective field theory, we find that selection rules due to U(2)_{q+e} enhance the importance of charged lepton flavor violation as a probe, where significant experimental progress is expected in the near future.

17.
FEMS Microbiol Ecol ; 100(5)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38599628

RESUMEN

Yeasts are prevalent in the open ocean, yet we have limited understanding of their ecophysiological adaptations, including their response to nitrogen availability, which can have a major role in determining the ecological potential of other planktonic microbes. In this study, we characterized the nitrogen uptake capabilities and growth responses of marine-occurring yeasts. Yeast isolates from the North Atlantic Ocean were screened for growth on diverse nitrogen substrates, and across a concentration gradient of three environmentally relevant nitrogen substrates: nitrate, ammonium, and urea. Three strains grew with enriched nitrate while two did not, demonstrating that nitrate utilization is present but not universal in marine yeasts, consistent with existing knowledge of nonmarine yeast strains. Naganishia diffluens MBA_F0213 modified the key functional trait of cell size in response to nitrogen concentration, suggesting yeast cell morphology changes along chemical gradients in the marine environment. Meta-analysis of the reference DNA barcode in public databases revealed that the genus Naganishia has a global ocean distribution, strengthening the environmental applicability of the culture-based observations. This study provides novel quantitative understanding of the ecophysiological and morphological responses of marine-derived yeasts to variable nitrogen availability in vitro, providing insight into the functional ecology of yeasts within pelagic open ocean environments.


Asunto(s)
Nitratos , Nitrógeno , Agua de Mar , Nitrógeno/metabolismo , Agua de Mar/microbiología , Nitratos/metabolismo , Océano Atlántico , Levaduras/metabolismo , Levaduras/genética , Levaduras/crecimiento & desarrollo , Compuestos de Amonio/metabolismo , Urea/metabolismo
18.
Ecol Lett ; 27(3): e14412, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38549269

RESUMEN

Agricultural intensification not only increases food production but also drives widespread biodiversity decline. Increasing landscape heterogeneity has been suggested to increase biodiversity across habitats, while increasing crop heterogeneity may support biodiversity within agroecosystems. These spatial heterogeneity effects can be partitioned into compositional (land-cover type diversity) and configurational heterogeneity (land-cover type arrangement), measured either for the crop mosaic or across the landscape for both crops and semi-natural habitats. However, studies have reported mixed responses of biodiversity to increases in these heterogeneity components across taxa and contexts. Our meta-analysis covering 6397 fields across 122 studies conducted in Asia, Europe, North and South America reveals consistently positive effects of crop and landscape heterogeneity, as well as compositional and configurational heterogeneity for plant, invertebrate, vertebrate, pollinator and predator biodiversity. Vertebrates and plants benefit more from landscape heterogeneity, while invertebrates derive similar benefits from both crop and landscape heterogeneity. Pollinators benefit more from configurational heterogeneity, but predators favour compositional heterogeneity. These positive effects are consistent for invertebrates and vertebrates in both tropical/subtropical and temperate agroecosystems, and in annual and perennial cropping systems, and at small to large spatial scales. Our results suggest that promoting increased landscape heterogeneity by diversifying crops and semi-natural habitats, as suggested in the current UN Decade on Ecosystem Restoration, is key for restoring biodiversity in agricultural landscapes.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Europa (Continente) , Productos Agrícolas , Agricultura/métodos
19.
ISME Commun ; 4(1): ycae003, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38545624
20.
J Mol Biol ; 436(9): 168544, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38508303

RESUMEN

Bacteriophage T4 gene 32 protein (gp32) is a single-stranded DNA (ssDNA) binding protein essential for DNA replication. gp32 forms stable protein filaments on ssDNA through cooperative interactions between its core and N-terminal domain. gp32's C-terminal domain (CTD) is believed to primarily help coordinate DNA replication via direct interactions with constituents of the replisome. However, the exact mechanisms of these interactions are not known, and it is unclear how tightly-bound gp32 filaments are readily displaced from ssDNA as required for genomic processing. Here, we utilized truncated gp32 variants to demonstrate a key role of the CTD in regulating gp32 dissociation. Using optical tweezers, we probed the binding and dissociation dynamics of CTD-truncated gp32, *I, to an 8.1 knt ssDNA molecule and compared these measurements with those for full-length gp32. The *I-ssDNA helical filament becomes progressively unwound with increased protein concentration but remains significantly more stable than that of full-length, wild-type gp32. Protein oversaturation, concomitant with filament unwinding, facilitates rapid dissociation of full-length gp32 from across the entire ssDNA segment. In contrast, *I primarily unbinds slowly from only the ends of the cooperative clusters, regardless of the protein density and degree of DNA unwinding. Our results suggest that the CTD may constrain the relative twist angle of proteins within the ssDNA filament such that upon critical unwinding the cooperative interprotein interactions largely vanish, facilitating prompt removal of gp32. We propose a model of CTD-mediated gp32 displacement via internal restructuring of its filament, providing a mechanism for rapid ssDNA clearing during genomic processing.


Asunto(s)
Bacteriófago T4 , ADN de Cadena Simple , Proteínas de Unión al ADN , Unión Proteica , Proteínas Virales , Bacteriófago T4/genética , Bacteriófago T4/metabolismo , Replicación del ADN , ADN de Cadena Simple/metabolismo , ADN de Cadena Simple/genética , ADN Viral/genética , ADN Viral/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/química , Pinzas Ópticas , Dominios Proteicos , Proteínas Virales/metabolismo , Proteínas Virales/genética , Proteínas Virales/química
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