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1.
bioRxiv ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38659969

RESUMO

Multisystem Inflammatory Syndrome in Children (MIS-C) is a severe complication of SARS-CoV-2 infection characterized by multi-organ involvement and inflammation. Testing of cellular function ex vivo to understand the aberrant immune response in MIS-C is limited. Despite strong antibody production in MIS-C, SARS-CoV-2 nucleic acid testing can remain positive for 4-6 weeks after infection. Therefore, we hypothesized that dysfunctional cell-mediated antibody responses downstream of antibody production may be responsible for delayed clearance of viral products in MIS-C. In MIS-C, monocytes were hyperfunctional for phagocytosis and cytokine production, while natural killer (NK) cells were hypofunctional for both killing and cytokine production. The decreased NK cell cytotoxicity correlated with an NK exhaustion marker signature and systemic IL-6 levels. Potentially providing a therapeutic option, cellular engagers of CD16 and SARS-CoV-2 proteins were found to rescue NK cell function in vitro. Together, our results reveal dysregulation in antibody-mediated cellular responses unique to MIS-C that likely contribute to the immune pathology of this disease.

2.
Orthop J Sports Med ; 12(3): 23259671241232707, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38465258

RESUMO

Background: Social media (SM) use by orthopaedic surgeons is becoming increasingly common; nonetheless, it needs to be clarified how patients perceive the content posted by physicians. Purpose: To characterize SM content posted by orthopaedic surgeons while investigating patient perceptions of this content and how it may influence their health care decisions. Study Design: Cross-sectional study. Methods: Posts on SM outlets by orthopaedic surgeons were reviewed and categorized. A survey to assess patient perception of these categories was administered between December 2021 and February 2022 in the clinics of 3 orthopaedic surgeons. Survey results were analyzed for differences in patient SM use and perception of SM content types. Results: There were 250 completed surveys. SM use was high among all age groups; however, the 18 to 24 years (87.1%) and 25 to 34 years (86.4%) age groups were more likely than older age groups to report daily use (P = .002). Overall, 17% of patients reported using SM to see information about their health care at least once per month, 21% reported reviewing the SM account of a physician at least once per month, 19% reported that they were likely or very likely to view the SM account of their physician, and 23% reported that SM content was likely or very likely to influence which physician they see. Patients held the most consistently positive view of posts that educated patients, discussed sports team coverage, and provided patient testimonials. Patients had consistently neutral views of posts educating colleagues, discussing presentations at national meetings, displaying aspects of surgeons' personal lives, and supporting marginalized groups. Several post categories elicited highly polarized responses-including those discussing research publications and showing surgical techniques or pictures/videos taken during surgery. Respondents had a consistently negative response to posts making political statements. Conclusion: SM is likely a useful tool to help physicians interact with patients. Physicians who wish to interact with patients should consider posting content viewed most positively-including posts educating patients, discussing sports team coverage, and providing patient testimonials. Content that is viewed less favorably should be posted sparingly or with a sensitive tag.

3.
J Cell Sci ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506228

RESUMO

Clathrin-mediated endocytosis (CME) is vital for the regulation of plant growth and development by controlling plasma membrane protein composition and cargo uptake. CME relies on the precise recruitment of regulators for vesicle maturation and release. Homologues of components of mammalian vesicle scission are strong candidates to be part of the scission machinery in plants, but the precise roles of these proteins in this process are not fully understood. Here, we characterised the roles of Plant Dynamin-Related Proteins 2 (DRP2s) and SH3-domain containing protein 2 (SH3P2), the plant homologue to Dynamins' recruiters, like Endophilin and Amphiphysin, in the CME by combining high-resolution imaging of endocytic events in vivo and characterisation of the purified proteins in vitro. Although DRP2s and SH3P2 arrive similarly late during CME and physically interact, genetic analysis of the sh3p123 triple-mutant and complementation assays with non-SH3P2-interacting DRP2 variants suggests that SH3P2 does not directly recruit DRP2s to the site of endocytosis. These observations imply that despite the presence of many well-conserved endocytic components, plants have acquired a distinct mechanism for CME.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38512283

RESUMO

BACKGROUND: Subclinical inflammation and cognitive deficits have been separately associated with asymptomatic Plasmodium falciparum infections in schoolchildren. However, whether parasite-induced inflammation is associated with worse cognition has not been addressed. We conducted a cross-sectional pilot study to better assess the effect of asymptomatic P. falciparum parasitemia and inflammation on cognition in Kenyan schoolchildren. METHODS: We enrolled 240 children aged 7-14 years residing in high malaria transmission in Western Kenya. Children performed five fluid cognition tests from a culturally adapted NIH toolbox and provided blood samples for blood smears and laboratory testing. Parasite densities and plasma concentrations of 14 cytokines were determined by quantitative PCR and multiplex immunoassay, respectively. Linear regression models were used to determine the effects of parasitemia and plasma cytokine concentrations on each of the cognitive scores as well as a composite cognitive score while controlling for age, gender, maternal education, and an interaction between age and P. falciparum infection status. RESULTS: Plasma concentrations of TNF, IL-6, IL-8, and IL-10 negatively correlated with the composite score and at least one of the individual cognitive tests. Parasite density in parasitemic children negatively correlated with the composite score and measures of cognitive flexibility and attention. In the adjusted model, parasite density and TNF, but not P. falciparum infection status, independently predicted lower cognitive composite scores. By mediation analysis, TNF significantly mediated ~29% of the negative effect of parasitemia on cognition. CONCLUSION: Among schoolchildren with PCR-confirmed asymptomatic P. falciparum infections, the negative effect of parasitemia on cognition could be mediated, in part, by subclinical inflammation. Additional studies are needed to validate our findings in settings of lower malaria transmission and address potential confounders that could affect both inflammation and cognitive performance.

5.
HERD ; : 19375867231222563, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38259242

RESUMO

OBJECTIVES: A working group conducted a survey on the use of the principle of buffer space (BS), which in case of emergencies, could benefit healthcare settings. The aim of the preliminary investigation is to define new research lines in hospitals' functional design. BACKGROUND: The global experience of the COVID-19 pandemic highlighted challenges faced by hospitals when responding promptly to emergencies, including spatial reorganization and suspension of ordinary medical activities for ensuring adequate management of the emergency surge of patients. METHODS: The group designed questionnaires to be administered to healthcare staff and healthcare designers aimed at understanding varied conceptions and features of BSs. Content across the two surveys overlapped significantly, allowing for direct comparisons of responses, while also including tailored questions in relation to the respective experience and skills of the two groups of respondents. RESULTS: 102 healthcare professionals and 56 designers took part to the survey. Analysis of the responses permitted for initial recommendations regarding BS typology including (a) proximity to the emergency department (ED), intensive care units (ICUs), and inpatient wards (IWs); (b) location within hospitals but separate from other medical areas; (c) need for independent access; (d) organizational and spatial features similar to ED, ICUs, and IWs; (e) existing as a fully flexible operational space; and (f) BS bed capacity to be approximately 12% of ED beds. CONCLUSIONS: Although the analysis is related to the Italian context, the expansion of this preliminary research to alternate healthcare facilities and geographic areas is necessary for reaching a wide consensus by different professionals on this field. It serves as a starting point for future investigations regarding the implementation of BS in hospital settings.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37794723

RESUMO

BACKGROUND: Cognitive impairment are among the core features of schizophrenia, experienced by up to 75% of patients. Available treatment options for schizophrenia including dopamine antagonists and traditional antipsychotic medications have not been shown to confer significant benefits on cognitive deficits. Contrary to the focus on management of positive symptoms in schizophrenia, cognitive abilities are main predictor of independent living skills, functional abilities, employment, engagement in relapse prevention, and patients' subjective sense of well-being and quality of life. This review aims to provide a summary of recent literature on pharmacological options for the treatment of cognitive deficits in schizophrenia. METHODS: We conducted a literature search of studies from 2011 to 2021 across four electronic databases including PubMed, PsycInfo, MEDLINE, and Embase. Human studies using a pharmacological treatment for cognitive impairment in schizophrenia were included. RESULTS: Fifty-eight eligible publications, representing 11 pharmacological classes, were included in this review. Major limitations involved small sample size, methodological limitations as well as heterogeneity of participants and outcome measures. CONCLUSIONS: Overall evidence remains inconclusive for any pharmacological classes studied for the treatment of cognitive deficits in schizophrenia. Methodological limitations in a majority of the studies rendered their findings preliminary. We further discuss possible explanations for these findings that could guide future research.

7.
Dev Psychobiol ; 65(7): e22421, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37860907

RESUMO

Despite early-life disadvantage (ELD) in humans being a highly heterogenous construct, it consistently predicts negative neurobehavioral outcomes. The numerous environmental contributors and neural mechanisms underlying ELD remain unclear, though. We used a laboratory rat model to evaluate the effects of limited resources and/or heavy metal exposure on mothers and their adult male and female offspring. Dams and litters were chronically exposed to restricted (1-cm deep) or ample (4-cm deep) home cage bedding postpartum, with or without lead acetate (0.1%) in their drinking water from insemination through 1-week postweaning. Restricted-bedding mothers showed more pup-directed behaviors and behavioral fragmentation, while lead-exposed mothers showed more nestbuilding. Restricted bedding-raised male offspring showed higher anxiety and aggression. Either restricted bedding or lead exposure impaired goal-directed performance in a reinforcer devaluation task in females, whereas restricted bedding alone disrupted it in males. Lead exposure, but not limited bedding, also reduced sucrose reward sensitivity in a progressive ratio task in females. D1 and D2 receptor mRNA in the medial prefrontal cortex and nucleus accumbens (NAc) were each affected by the early-life treatments and differently between the sexes. Most notably, adult males (but not females) exposed to both early-life treatments had greatly increased D1 receptor mRNA in the NAc core. These results illuminate neural mechanisms through which ELD threatens neurobehavioral development and highlight forebrain dopamine as a factor.


Assuntos
Dopamina , Receptores Dopaminérgicos , Ratos , Animais , Humanos , Masculino , Feminino , Dopamina/metabolismo , Receptores Dopaminérgicos/metabolismo , Chumbo/metabolismo , Chumbo/farmacologia , Núcleo Accumbens/metabolismo , Ansiedade , Agressão , Recompensa , RNA Mensageiro/metabolismo
8.
Genetics ; 225(3)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37811798

RESUMO

Candida albicans, a normal member of the human microbiome and an opportunistic fungal pathogen, undergoes several morphological transitions. One of these transitions is white-opaque switching, where C. albicans alternates between 2 stable cell types with distinct cellular and colony morphologies, metabolic preferences, mating abilities, and interactions with the innate immune system. White-to-opaque switching is regulated by mating type; it is repressed by the a1/α2 heterodimer in a/α cells, but this repression is lifted in a/a and α/α mating type cells (each of which are missing half of the repressor). The widely used C. albicans reference strain, SC5314, is unusual in that white-opaque switching is completely blocked when the cells are a/α; in contrast, most other C. albicans a/α strains can undergo white-opaque switching at an observable level. In this paper, we uncover the reason for this difference. We show that, in addition to repression by the a1/α2 heterodimer, SC5314 contains a second block to white-opaque switching: 4 transcription regulators of filamentous growth are upregulated in this strain and collectively suppress white-opaque switching. This second block is missing in the majority of clinical strains, and, although they still contain the a1/α2 heterodimer repressor, they exhibit a/α white-opaque switching at an observable level. When both blocks are absent, white-opaque switching occurs at very high levels. This work shows that white-opaque switching remains intact across a broad group of clinical strains, but the precise way it is regulated and therefore the frequency at which it occurs varies from strain to strain.


Assuntos
Candida albicans , Proteínas Fúngicas , Humanos , Candida albicans/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos Tipo Acasalamento , Fenótipo , Comunicação Celular , Regulação Fúngica da Expressão Gênica
10.
Proc Natl Acad Sci U S A ; 120(28): e2302445120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399378

RESUMO

Cells regulate gene expression by the specific binding of transcription regulators to cis-regulatory sequences. Pair-wise cooperativity between regulators-whereby two different regulators physically interact and bind DNA in a cooperative manner-is common and permits complex modes of gene regulation. Over evolutionary timescales, the formation of new combinations of regulators represents a major source of phenotypic novelty, facilitating new network structures. How functional, pair-wise cooperative interactions arise between regulators is poorly understood, despite the abundance of examples in extant species. Here, we explore a protein-protein interaction between two ancient transcriptional regulators-the homeodomain protein Matα2 and the MADS box protein Mcm1-that was gained approximately 200 million y ago in a clade of ascomycete yeasts that includes Saccharomyces cerevisiae. By combining deep mutational scanning with a functional selection for cooperative gene expression, we tested millions of possible alternative evolutionary solutions to this interaction interface. The artificially evolved, functional solutions are highly degenerate, with diverse amino acid chemistries permitted at all positions but with widespread epistasis limiting success. Nonetheless, approximately ~45% of the random sequences sampled function as well or better in controlling gene expression than the naturally evolved sequence. From these variants (which are unconstrained by historical contingency), we discern structural rules and epistatic constraints governing the emergence of cooperativity between these two transcriptional regulators. This work provides a mechanistic basis for long-standing observations of transcription network plasticity and highlights the importance of epistasis in the evolution of new protein-protein interactions.


Assuntos
Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Proteínas de Homeodomínio/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulação da Expressão Gênica , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
11.
mBio ; 14(4): e0137623, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37493629

RESUMO

The fungal pathogen Candida auris represents a severe threat to hospitalized patients. Its resistance to multiple classes of antifungal drugs and ability to spread and resist decontamination in healthcare settings make it especially dangerous. We screened 1,990 clinically approved and late-stage investigational compounds for the potential to be repurposed as antifungal drugs targeting C. auris and narrowed our focus to five Food and Drug Administration (FDA)-approved compounds with inhibitory concentrations under 10 µM for C. auris and significantly lower toxicity to three human cell lines. These compounds, some of which had been previously identified in independent screens, include three dihalogenated 8-hydroxyquinolines: broxyquinoline, chloroxine, and clioquinol. A subsequent structure-activity study of 32 quinoline derivatives found that 8-hydroxyquinolines, especially those dihalogenated at the C5 and C7 positions, were the most effective inhibitors of C. auris. To pursue these compounds further, we exposed C. auris to clioquinol in an extended experimental evolution study and found that C. auris developed only twofold to fivefold resistance to the compound. DNA sequencing of resistant strains and subsequent verification by directed mutation in naive strains revealed that resistance was due to mutations in the transcriptional regulator CAP1 (causing upregulation of the drug transporter MDR1) and in the drug transporter CDR1. These mutations had only modest effects on resistance to traditional antifungal agents, and the CDR1 mutation rendered C. auris more susceptible to posaconazole. This observation raises the possibility that a combination treatment involving an 8-hydroxyquinoline and posaconazole might prevent C. auris from developing resistance to this established antifungal agent. IMPORTANCE The rapidly emerging fungal pathogen Candida auris represents a growing threat to hospitalized patients, in part due to frequent resistance to multiple classes of antifungal drugs. We identify a class of compounds, the dihalogenated 8-hydroxyquinolines, with broad fungistatic ability against a diverse collection of 13 strains of C. auris. Although this compound has been identified in previous screens, we extended the analysis by showing that C. auris developed only modest twofold to fivefold increases in resistance to this class of compounds despite long-term exposure; a noticeable difference from the 30- to 500-fold increases in resistance reported for similar studies with commonly used antifungal drugs. We also identify the mutations underlying the resistance. These results suggest that the dihalogenated 8-hydroxyquinolines are working inside the fungal cell and should be developed further to combat C. auris and other fungal pathogens. Lohse and colleagues characterize a class of compounds that inhibit the fungal pathogen C. auris. Unlike many other antifungal drugs, C. auris does not readily develop resistance to this class of compounds.


Assuntos
Antifúngicos , Clioquinol , Humanos , Antifúngicos/metabolismo , Candida auris , Candida , Clioquinol/farmacologia , Clioquinol/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica/genética
12.
J Emerg Manag ; 21(7): 167-184, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37154452

RESUMO

OBJECTIVES: This study aims to provide metadesign indications for the improvement of healthcare facilities, emphasizing the role of spatial design in the management of epidemic health emergencies. STUDY DESIGN: A parallel mixed-method study including literature reviews, survey creation, and survey distribution was performed. METHODS: Data were collected between August and October 2020 capturing information related to the first wave of the COVID-19 pandemic, utilizing a review of existing literature, a comparison of existing hospital planning guidelines and assessment tools, and distribution of a survey to analyze design changes within selected Italian hospitals. RESULTS: Among the changes identified, the most frequently identified included the conversion of space into intensive care units, space expansion, and the usage of wayfinding strategies for the reduction of cross-contamination risks. There was limited attention given to solutions with a human-centered approach, and those that addressed physical and psychological well-being of all users, including healthcare staff. The solutions were collected and systematized into a list of metadesign guidelines. CONCLUSIONS: The resulting indications represent a starting point for developing design solutions to aid healthcare facilities in facing future epidemics.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Atenção à Saúde , Hospitais , Itália/epidemiologia
13.
Proc Natl Acad Sci U S A ; 120(21): e2220568120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186823

RESUMO

A fundamental question in biology is how a eukaryotic cell type can be stably maintained through many rounds of DNA replication and cell division. In this paper, we investigate this question in a fungal species, Candida albicans, where two different cells types (white and opaque) arise from the same genome. Once formed, each cell type is stable for thousands of generations. Here, we investigate the mechanisms underlying opaque cell "memory." Using an auxin-mediated degradation system, we rapidly removed Wor1, the primary transcription activator of the opaque state and, using a variety of methods, determined how long cells can maintain the opaque state. Within approximately 1 h of Wor1 destruction, opaque cells irreversibly lose their memory and switch to the white cell state. This observation rules out several competing models for cell memory and demonstrates that the continuous presence of Wor1 is needed to maintain the opaque cell state-even across a single cell division cycle. We also provide evidence for a threshold concentration of Wor1 in opaque cells, below which opaque cells irreversibly switch to white cells. Finally, we provide a detailed description of the gene expression changes that occur during this switch in cell types.


Assuntos
Eucariotos , Células Eucarióticas , Eucariotos/metabolismo , Células Eucarióticas/metabolismo , Candida albicans/genética , Candida albicans/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ciclo Celular , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/metabolismo , Fenótipo
14.
Genetics ; 224(2)2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37119800

RESUMO

Over evolutionary timescales, the logic and pattern of cell-type specific gene expression can remain constant, yet the molecular mechanisms underlying such regulation can drift between alternative forms. Here, we document a new example of this principle in the regulation of the haploid-specific genes in a small clade of fungal species. For most ascomycete fungal species, transcription of these genes is repressed in the a/α cell type by a heterodimer of two homeodomain proteins, Mata1 and Matα2. We show that in the species Lachancea kluyveri, most of the haploid-specific genes are regulated in this way, but repression of one haploid-specific gene (GPA1) requires, in addition to Mata1 and Matα2, a third regulatory protein, Mcm1. Model building, based on x-ray crystal structures of the three proteins, rationalizes the requirement for all three proteins: no single pair of the proteins is optimally arranged, and we show that no single pair can bring about repression. This case study exemplifies the idea that the energy of DNA binding can be "shared out" in different ways and can result in different DNA-binding solutions across different genes-while maintaining the same overall pattern of gene expression.


Assuntos
Ascomicetos , Proteínas de Saccharomyces cerevisiae , Proteínas Fúngicas/metabolismo , Saccharomyces cerevisiae/genética , Proteínas Repressoras/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Haploidia , Filogenia , Ascomicetos/genética , DNA/química , Regulação Fúngica da Expressão Gênica , Proteínas de Homeodomínio/genética
15.
Physiol Behav ; 265: 114177, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36967031

RESUMO

Puberty is a high-risk period for the development of dysregulated eating, including binge eating. While risk for binge eating in animals and humans increases in both males and females during puberty, the increased prevalence is significantly greater in females. Emerging data suggest that the organizational effects of gonadal hormones may contribute to the female preponderance of binge eating. In this narrative review, we discuss studies conducted in animals that have examined these organizational effects as well as the neural systems that may serve as intermediary mechanisms. Relatively few studies have been conducted, but data thus far suggest that pubertal estrogens may organize risk for binge eating, potentially by altering key circuits in brain reward pathways. These promising results highlight the need for future studies to directly test organizational effects of pubertal hormones using hormone replacement techniques and circuit-level manipulations that can identify pathways contributing to binge eating across development.


Assuntos
Transtorno da Compulsão Alimentar , Bulimia , Humanos , Masculino , Ratos , Feminino , Animais , Maturidade Sexual , Estrogênios/metabolismo , Hormônios Gonadais , Puberdade
16.
J Chem Phys ; 158(8): 084101, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36859080

RESUMO

A new algorithm based on a rigorous theorem and quantum data computationally mined from element 118 guarantees automated construction of initial Fermi-Löwdin-Orbital (FLO) starting points for all elements in the Periodic Table. It defines a means for constructing a small library of scalable FLOs for universal use in molecular and solid-state calculations. The method can be systematically improved for greater efficiency and for applications to excited states such as x-ray excitations and optically silent excitations. FLOs were introduced to recast the Perdew-Zunger self-interaction correction (PZSIC) into an explicit unitarily invariant form. The FLOs are generated from a set of N quasi-classical electron positions, referred to as Fermi-Orbital descriptors (FODs), and a set of N-orthonormal single-electron orbitals. FOD positions, when optimized, minimize the PZSIC total energy. However, creating sets of starting FODs that lead to a positive definite Fermi orbital overlap matrix has proven to be challenging for systems composed of open-shell atoms and ions. The proof herein guarantees the existence of a FLOSIC solution and further guarantees that if a solution for N electrons is found, it can be used to generate a minimum of N - 1 and a maximum of 2N - 2 initial starting points for systems composed of a smaller number of electrons. Applications to heavy and super-heavy atoms are presented. All starting solutions reported here were obtained from a solution for element 118, Oganesson.

17.
bioRxiv ; 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36824717

RESUMO

The fungal pathogen Candida auris represents a severe threat to hospitalized patients. Its resistance to multiple classes of antifungal drugs and ability to spread and resist decontamination in health-care settings make it especially dangerous. We screened 1,990 clinically approved and late-stage investigational compounds for the potential to be repurposed as antifungal drugs targeting C. auris and narrowed our focus to five FDA-approved compounds with inhibitory concentrations under 10 µM for C. auris and significantly lower toxicity to three human cell lines. These compounds, some of which had been previously identified in independent screens, include three dihalogenated 8-hydroxyquinolines: broxyquinoline, chloroxine, and clioquinol. A subsequent structure-activity study of 32 quinoline derivatives found that 8-hydroxyquinolines, especially those dihalogenated at the C5 and C7 positions, were the most effective inhibitors of C. auris . To pursue these compounds further, we exposed C. auris to clioquinol in an extended experimental evolution study and found that C. auris developed only 2- to 5-fold resistance to the compound. DNA sequencing of resistant strains and subsequent verification by directed mutation in naive strains revealed that resistance was due to mutations in the transcriptional regulator CAP1 (causing upregulation of the drug transporter MDR1 ) and in the drug transporter CDR1 . These mutations had only modest effects on resistance to traditional antifungal agents, and the CDR1 mutation rendered C. auris more sensitive to posaconazole. This observation raises the possibility that a combination treatment involving an 8-hydroxyquinoline and posaconazole might prevent C. auris from developing resistance to this established antifungal agent. Abstract Importance: The rapidly emerging fungal pathogen Candida auris represents a growing threat to hospitalized patients, in part due to frequent resistance to multiple classes of antifungal drugs. We identify a class of compounds, the dihalogenated hydroxyquinolines, with broad fungistatic ability against a diverse collection of 13 strains of C. auris . Although this compound has been identified in previous screens, we extended the analysis by showing that C. auris developed only modest 2- to 5-fold increases in resistance to this class of compounds despite long-term exposure; a noticeable difference from the 30- to 500- fold increases in resistance reported for similar studies with commonly used antifungal drugs. We also identify the mutations underlying the resistance. These results suggest that the dihalogenated hydroxyquinolines are working inside the fungal cell and should be developed further to combat C. auris and other fungal pathogens. Tweet: Lohse and colleagues characterize a class of compounds that inhibit the fungal pathogen C. auris . Unlike many other antifungal drugs, C. auris does not readily develop resistance to this class of compounds.

18.
PLoS One ; 18(1): e0280233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662710

RESUMO

Candida albicans is a normal member of the human microbiome and an opportunistic fungal pathogen. This species undergoes several morphological transitions, and here we consider white-opaque switching. In this switching program, C. albicans reversibly alternates between two cell types, named "white" and "opaque," each of which is normally stable across thousands of cell divisions. Although switching under most conditions is stochastic and rare, certain environmental signals or genetic manipulations can dramatically increase the rate of switching. Here, we report the identification of two new inputs which affect white-to-opaque switching rates. The first, exposure to sub-micromolar concentrations of (E,E)-farnesol, reduces white-to-opaque switching by ten-fold or more. The second input, an inferred PKA phosphorylation of residue T208 on the transcriptional regulator Efg1, increases white-to-opaque switching ten-fold. Combining these and other environmental inputs results in a variety of different switching rates, indicating that a given rate represents the integration of multiple inputs.


Assuntos
Candida albicans , Farneseno Álcool , Proteínas Fúngicas , Humanos , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candida albicans/metabolismo , Farneseno Álcool/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Técnicas Genéticas , Fenótipo , Fosforilação
19.
Plant Physiol ; 191(1): 528-541, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36308454

RESUMO

Dietary deficiencies of iron and zinc cause human malnutrition that can be mitigated by biofortified staple crops. Conventional breeding approaches to increase grain mineral concentrations in wheat (Triticum aestivum L.) have had only limited success, and our understanding of the genetic and physiological barriers to altering this trait is incomplete. Here we demonstrate that a transgenic approach combining endosperm-specific expression of the wheat VACUOLAR IRON TRANSPORTER gene TaVIT2-D with constitutive expression of the rice (Oryza sativa) NICOTIANAMINE SYNTHASE gene OsNAS2 significantly increases the total concentration of zinc and relocates iron to white-flour fractions. In two distinct bread wheat cultivars, we show that the so called VIT-NAS construct led to a two-fold increase in zinc in wholemeal flour, to ∼50 µg g-1. Total iron was not significantly increased, but redistribution within the grain resulted in a three-fold increase in iron in highly pure, roller-milled white flour, to ∼25 µg g-1. Interestingly, expression of OsNAS2 partially restored iron translocation to the aleurone, which is iron depleted in grain overexpressing TaVIT2 alone. A greater than three-fold increase in the level of the natural plant metal chelator nicotianamine in the grain of VIT-NAS lines corresponded with improved iron and zinc bioaccessibility in white flour. The growth of VIT-NAS plants in the greenhouse was indistinguishable from untransformed controls. Our results provide insights into mineral translocation and distribution in wheat grain and demonstrate that the individual and combined effects of the two transgenes can enhance the nutritional quality of wheat beyond what is possible by conventional breeding.


Assuntos
Farinha , Zinco , Humanos , Zinco/metabolismo , Farinha/análise , Triticum/genética , Triticum/metabolismo , Melhoramento Vegetal , Minerais , Grão Comestível/genética , Grão Comestível/metabolismo
20.
Clin Sports Med ; 42(1): 53-68, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36375870

RESUMO

Symptomatic rotator cuff pathology is a common musculoskeletal issue with evolving surgical indications. Most of the patients undergo some form of nonoperative treatment before considering surgical intervention. Understanding and optimizing nonoperative treatment modalities is an essential key to successful treatment. This article contains a review of the current literature regarding the risks, benefits, and alternatives of the most common injections used in the treatment of rotator cuff pathology. Injection options covered include corticosteroids, biologics including platelet-rich plasma and stem cells, hyaluronic acid, and nonsteroidal anti-inflammatory drugs.


Assuntos
Produtos Biológicos , Plasma Rico em Plaquetas , Lesões do Manguito Rotador , Humanos , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/terapia , Produtos Biológicos/uso terapêutico , Resultado do Tratamento
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