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2.
J Phys Chem A ; 128(37): 7816-7829, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39240216

RESUMO

The diradical benzyne isomers are excellent prototypes for evaluating the ability of an electronic structure method to describe static and dynamic correlation. The benzyne isomers are also interesting molecules with which to study the fundamentals of through-space and through-bond diradical coupling that is important in so many electronic device applications. In the current study, we utilize the multireference methods MC-SCF, MR-CISD, MR-CISD+Q, and MR-AQCC with an (8,8) complete active space that includes the σ, σ*, π and π* orbitals, to characterize the electronic structure of ortho-, meta- and para-benzyne. We also determine the adiabatic and vertical singlet-triplet splittings for these isomers. MR-AQCC and MR-CISD+Q produced energy gaps in good agreement with previously obtained experimental values. Geometries, orbital energies and unpaired electron densities show significant through-space coupling in the o- and m-benzynes, while p-benzyne shows through-bond coupling, explaining the dramatically different singlet-triplet gaps between the three isomers.

3.
J Infect Dis ; 228(Suppl 7): S488-S497, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37551415

RESUMO

The 3' untranslated regions (UTRs) of Ebola virus (EBOV) mRNAs are enriched in their AU content and therefore represent potential targets for RNA binding proteins targeting AU-rich elements (ARE-BPs). ARE-BPs are known to fine-tune RNA turnover and translational activity. We identified putative AREs within EBOV mRNA 3' UTRs and assessed whether they might modulate mRNA stability. Using mammalian and zebrafish embryo reporter assays, we show a conserved, ARE-BP-mediated stabilizing effect and increased reporter activity with the tested EBOV 3' UTRs. When coexpressed with the prototypic ARE-BP tristetraprolin (TTP, ZFP36) that mainly destabilizes its target mRNAs, the EBOV nucleoprotein (NP) 3' UTR resulted in decreased reporter gene activity. Coexpression of NP with TTP led to reduced NP protein expression and diminished EBOV minigenome activity. In conclusion, the enrichment of AU residues in EBOV 3' UTRs makes them possible targets for cellular ARE-BPs, leading to modulation of RNA stability and translational activity.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Animais , Regiões 3' não Traduzidas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ebolavirus/genética , Ebolavirus/metabolismo , Doença pelo Vírus Ebola/genética , Peixe-Zebra/metabolismo , Estabilidade de RNA/genética , Mamíferos
4.
J Virol ; 96(18): e0057422, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36073921

RESUMO

Ebola virus disease (EVD) is a complex infectious disease characterized by high inflammation, multiorgan failure, the dysregulation of innate and adaptive immune responses, and coagulation abnormalities. Evidence accumulated over the last 2 decades indicates that, during fatal EVD, the infection of antigen-presenting cells (APC) and the dysregulation of T cell immunity preclude a successful transition between innate and adaptive immunity, which constitutes a key disease checkpoint. In order to better understand the contribution of the APC-T cell crosstalk to EVD pathophysiology, we have developed avatar mice transplanted with human, donor-specific APCs and T cells. Here, we show that the transplantation of T cells and APCs from Ebola virus (EBOV)-naive individuals into avatar mice results in severe disease and death and that this phenotype is dependent on T cell receptor (TCR)-major histocompatibility complex (MCH) recognition. Conversely, avatar mice were rescued from death induced by EBOV infection after the transplantation of both T cells and plasma from EVD survivors. These results strongly suggest that protection from EBOV reinfection requires both cellular and humoral immune memory responses. IMPORTANCE The crosstalk between dendritic cells and T cells marks the transition between innate and adaptive immune responses, and it constitutes an important checkpoint in EVD. In this study, we present a mouse avatar model in which T cell and dendritic cell interactions from a specific donor can be studied during EVD. Our findings indicate that T cell receptor-major histocompatibility complex-mediated T cell-dendritic cell interactions are associated with disease severity, which mimics the main features of severe EVD in these mice. Resistance to an EBOV challenge in the model was achieved via the transplantation of both survivor T cells and plasma.


Assuntos
Comunicação Celular , Células Dendríticas , Ebolavirus , Doença pelo Vírus Ebola , Animais , Comunicação Celular/imunologia , Células Dendríticas/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/fisiopatologia , Humanos , Camundongos , Sobreviventes , Linfócitos T/imunologia , Linfócitos T/virologia
5.
Proc Natl Acad Sci U S A ; 117(26): 15332-15342, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32541020

RESUMO

Stem cells divide and differentiate to form all of the specialized cell types in a multicellular organism. In the Arabidopsis root, stem cells are maintained in an undifferentiated state by a less mitotically active population of cells called the quiescent center (QC). Determining how the QC regulates the surrounding stem cell initials, or what makes the QC fundamentally different from the actively dividing initials, is important for understanding how stem cell divisions are maintained. Here we gained insight into the differences between the QC and the cortex endodermis initials (CEI) by studying the mobile transcription factor SHORTROOT (SHR) and its binding partner SCARECROW (SCR). We constructed an ordinary differential equation model of SHR and SCR in the QC and CEI which incorporated the stoichiometry of the SHR-SCR complex as well as upstream transcriptional regulation of SHR and SCR. Our model prediction, coupled with experimental validation, showed that high levels of the SHR-SCR complex are associated with more CEI division but less QC division. Furthermore, our model prediction allowed us to propose the putative upstream SHR regulators SEUSS and WUSCHEL-RELATED HOMEOBOX 5 and to experimentally validate their roles in QC and CEI division. In addition, our model established the timing of QC and CEI division and suggests that SHR repression of QC division depends on formation of the SHR homodimer. Thus, our results support that SHR-SCR protein complex stoichiometry and regulation of SHR transcription modulate the division timing of two different specialized cell types in the root stem cell niche.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Células-Tronco/fisiologia , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Biomarcadores , Diferenciação Celular , Modelos Biológicos , Mutação , Fatores de Transcrição/genética
6.
Community Ment Health J ; 59(8): 1442-1451, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37314531

RESUMO

This manuscript reviews the unique challenges, barriers, and ethical implications of providing mental health services in rural and underserved areas. Community mental health centers in rural areas are often underserved due to shortages of mental health providers and limited resources. Individuals living in rural areas are at increased risk of developing mental health condition with limited access to mental health clinicians and healthcare facilities. These access to care issues are often exacerbated by geographical barriers as well as social, cultural, and economic challenges. A rural mental health professional may encounter several barriers to providing adequate care to individuals living in rural areas. For example, limited services and resources, geographic barriers, conflict between professional guidelines and community values, managing dual relationships, and challenges pertaining to confidentiality and privacy are several barriers to providing adequate care in rural areas. We will briefly summarize the primary ethical domains that are especially influenced by rural culture and the complex responsibilities of mental health providers in rural areas including barriers to care, crisis intervention, confidentiality, multiple relationships/dual roles, limits of competency, and rural mental healthcare practice implications.

7.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32817220

RESUMO

Lassa fever (LF) is a zoonotic viral hemorrhagic fever caused by Lassa virus (LASV), which is endemic to West African countries. Previous studies have suggested an important role for T-cell-mediated immunopathology in LF pathogenesis, but the mechanisms by which T cells influence disease severity and outcome are not well understood. Here, we present a multiparametric analysis of clinical immunology data collected during the 2017-2018 Lassa fever outbreak in Nigeria. During the acute phase of LF, we observed robust activation of the polyclonal T-cell repertoire, which included LASV-specific and antigenically unrelated T cells. However, severe and fatal LF cases were characterized by poor LASV-specific effector T-cell responses. Severe LF was also characterized by the presence of circulating T cells with homing capacity to inflamed tissues, including the gut mucosa. These findings in LF patients were recapitulated in a mouse model of LASV infection, in which mucosal exposure resulted in remarkably high lethality compared to skin exposure. Taken together, our findings indicate that poor LASV-specific T-cell responses and activation of nonspecific T cells with homing capacity to inflamed tissues are associated with severe LF.IMPORTANCE Lassa fever may cause severe disease in humans, in particular in areas of endemicity like Sierra Leone and Nigeria. Despite its public health importance, the pathophysiology of Lassa fever in humans is poorly understood. Here, we present clinical immunology data obtained in the field during the 2018 Lassa fever outbreak in Nigeria indicating that severe Lassa fever is associated with activation of T cells antigenically unrelated to Lassa virus and poor Lassa virus-specific effector T-cell responses. Mechanistically, we show that these bystander T cells express defined tissue homing signatures that suggest their recruitment to inflamed tissues and a putative role of these T cells in immunopathology. These findings open a window of opportunity to consider T-cell targeting as a potential postexposure therapeutic strategy against severe Lassa fever, a hypothesis that could be tested in relevant animal models, such as nonhuman primates.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Surtos de Doenças , Mucosa Intestinal/imunologia , Febre Lassa/imunologia , Vírus Lassa/patogenicidade , Ativação Linfocitária , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Humanos , Lactente , Recém-Nascido , Integrina beta1/genética , Integrina beta1/imunologia , Interferon gama/genética , Interferon gama/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Febre Lassa/genética , Febre Lassa/mortalidade , Febre Lassa/virologia , Vírus Lassa/crescimento & desenvolvimento , Vírus Lassa/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/genética , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Nigéria/epidemiologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Pele/imunologia , Pele/patologia , Pele/virologia , Análise de Sobrevida , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
9.
Addict Disord Their Treat ; 18(2): 70-80, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31130827

RESUMO

OBJECTIVES: Women suffer more severe consequences related to heavy drinking than men. Relative to men, women who are heavy drinkers experience higher severity of medical, psychiatric, and social problems, even when they have fewer years drinking. Currently there are few gender-specific, evidence-based interventions for heavy drinking among women. METHODS: A randomized clinical trial was conducted with 215 women with alcohol problems. Half were randomly assigned to receive a 9-session, "Intensive Motivational Interviewing" (IMI) intervention (N=107) and half were randomly assigned to a standard single session of MI (SMI) along with 8 sessions of nutritional education (N=108) to achieve time equivalence. Both conditions received weekly outpatient group counseling. Follow-up interviews were conducted at 2 months. Primary outcomes included percent drinking days (PDD), percent heavy drinking days (PHDD, 4+ drinks), and the Addiction Severity Index (ASI) Alcohol scale. Longitudinal changes were assessed using generalized estimating equations (GEE). RESULTS: The sample was predominantly white (83.3%), college educated (61.4%), and married (53.5%). The mean age was 50.9 (sd = 11.3). Relative to baseline, both study conditions showed significant reductions in PDD, PHDD, and ASI alcohol severity (p<.001). Among heavy drinkers, defined as women drinking 14+ days to the point of intoxication over the past 30 days at baseline (N=153), those assigned to IMI (n=67) showed larger reductions in PDD (p<.01) and PHDD (p<.05) at 2-months compared to women receiving SMI. CONCLUSIONS: Findings support the efficacy of IMI for heavy drinking among women. Additional studies are needed that assess drinking over longer time periods.

10.
Breast Cancer Res Treat ; 172(2): 445-452, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30136009

RESUMO

PURPOSE: This observational study was designed to measure baseline energy parameters and body composition in early-stage breast cancer patients, and to follow changes during and after various modalities of treatment. This will provide information to aid in the development of individualized physical activity intervention strategies. METHODS: Patients with newly diagnosed stage 0-III breast cancer were enrolled into three cohorts: A (local therapy alone), B (endocrine therapy), or C (chemotherapy with or without endocrine therapy). At baseline, 6 months, and 12 months, subjects underwent a stationary bicycle protocol to assess power generation and DEXA to assess body composition. RESULTS: Eighty-three patients enrolled. Patients had low and variable levels of power generation at baseline (mean power per kilogram lean mass 1.55 W/kg, SD 0.88). Power normalized to lean body mass (W/kg) decreased significantly, and similarly, by 6 months in cohorts B (1.42-1.04 W/kg, p = 0.008) and C (1.53-1.18 W/kg, p < 0.001). In all cohorts, there was no recovery of power generation by 12 months. Cohort C lost lean body mass (- 1.5 kg, p = 0.007), while cohort B maintained lean body mass (- 0.2 kg, p = 0.68), despite a similar trajectory in loss of power. Seven patients developed sarcopenia during the study period, including four patients who did not receive any chemotherapy (cohort B). CONCLUSIONS: The stationary bike protocol was feasible, easy, and acceptable to patients as a way to measure energetic capacity in a clinical setting. Early-stage breast cancer patients had low and variable levels of power generation, which worsened following primary therapy and did not show evidence of 'spontaneous recovery' by 12 months. Effective physical activity interventions will need to be personalized, accounting for both baseline ability and the effect of treatment.


Assuntos
Neoplasias da Mama/terapia , Metabolismo Energético/fisiologia , Adulto , Idoso , Composição Corporal/fisiologia , Índice de Massa Corporal , Neoplasias da Mama/fisiopatologia , Estudos de Coortes , Terapia Combinada , Tratamento Farmacológico , Exercício Físico , Feminino , Terapia de Reposição Hormonal , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias
11.
J Virol ; 90(16): 7268-7284, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27252530

RESUMO

UNLABELLED: A hallmark of Ebola virus (EBOV) infection is the formation of viral inclusions in the cytoplasm of infected cells. These viral inclusions contain the EBOV nucleocapsids and are sites of viral replication and nucleocapsid maturation. Although there is growing evidence that viral inclusions create a protected environment that fosters EBOV replication, little is known about their role in the host response to infection. The cellular stress response is an effective antiviral strategy that leads to stress granule (SG) formation and translational arrest mediated by the phosphorylation of a translation initiation factor, the α subunit of eukaryotic initiation factor 2 (eIF2α). Here, we show that selected SG proteins are sequestered within EBOV inclusions, where they form distinct granules that colocalize with viral RNA. These inclusion-bound (IB) granules are functionally and structurally different from canonical SGs. Formation of IB granules does not indicate translational arrest in the infected cells. We further show that EBOV does not induce formation of canonical SGs or eIF2α phosphorylation at any time postinfection but is unable to fully inhibit SG formation induced by different exogenous stressors, including sodium arsenite, heat, and hippuristanol. Despite the sequestration of SG marker proteins into IB granules, canonical SGs are unable to form within inclusions, which we propose might be mediated by a novel function of VP35, which disrupts SG formation. This function is independent of VP35's RNA binding activity. Further studies aim to reveal the mechanism for SG protein sequestration and precise function within inclusions. IMPORTANCE: Although progress has been made developing antiviral therapeutics and vaccines against the highly pathogenic Ebola virus (EBOV), the cellular mechanisms involved in EBOV infection are still largely unknown. To better understand these intracellular events, we investigated the cellular stress response, an antiviral pathway manipulated by many viruses. We show that EBOV does not induce formation of stress granules (SGs) in infected cells and is therefore unrestricted by their concomitant translational arrest. We identified SG proteins sequestered within viral inclusions, which did not impair protein translation. We further show that EBOV is unable to block SG formation triggered by exogenous stress early in infection. These findings provide insight into potential targets of therapeutic intervention. Additionally, we identified a novel function of the interferon antagonist VP35, which is able to disrupt SG formation.


Assuntos
Citoplasma/virologia , Ebolavirus/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Fatores Imunológicos/análise , Corpos de Inclusão Viral/virologia , Estresse Fisiológico , Proteínas Virais Reguladoras e Acessórias/metabolismo , Animais , Linhagem Celular , Grânulos Citoplasmáticos/metabolismo , Ebolavirus/imunologia , Proteínas de Choque Térmico/análise , Humanos , Corpos de Inclusão Viral/química
12.
Mol Ecol ; 26(10): 2796-2811, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28028864

RESUMO

Geographically separated populations tend to be less connected by gene flow, as a result of physical or nonphysical barriers preventing dispersal, and this can lead to genetic structure. In this context, highly mobile organisms such as seabirds are interesting because the small effect of physical barriers means nonphysical ones may be relatively more important. Here, we use microsatellite and mitochondrial data to explore the genetic structure and phylogeography of Atlantic and Mediterranean populations of a European endemic seabird, the European shag, Phalacrocorax aristotelis, and identify the primary drivers of their diversification. Analyses of mitochondrial markers revealed three phylogenetic lineages grouping the North Atlantic, Spanish/Corsican and eastern Mediterranean populations, apparently arising from fragmentation during the Pleistocene followed by range expansion. These traces of historical fragmentation were also evident in the genetic structure estimated by microsatellite markers, despite significant contemporary gene flow among adjacent populations. Stronger genetic structure, probably promoted by landscape, philopatry and local adaptation, was found among distant populations and those separated by physical and ecological barriers. This study highlights the enduring effect of Pleistocene climatic changes on shag populations, especially within the Mediterranean Basin, and suggests a role for cryptic northern refugia, as well as known southern refugia, on the genetic structure of European seabirds. Finally, it outlines how contemporary ecological barriers and behavioural traits may maintain population divergence, despite long-distance dispersal triggered by extreme environmental conditions (e.g. population crashes).


Assuntos
Aves/genética , Genética Populacional , Filogenia , Animais , DNA Mitocondrial/genética , Fluxo Gênico , Variação Genética , Repetições de Microssatélites , Filogeografia , Análise de Sequência de DNA
13.
Ecology ; 96(8): 2117-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26405737

RESUMO

The "landscape of fear" model has been proposed as a unifying concept in ecology, describing, in part, how animals behave and move about in their environment. The basic model predicts that as an animal's landscape changes from low to high risk of predation, prey species will alter their behavior to risk avoidance. However, studies investigating and evaluating the landscape of fear model across large spatial scales (tens to hundreds of thousands of square kilometers) in dynamic, open, aquatic systems involving apex predators and highly mobile prey are lacking. To address this knowledge gap, we investigated predator-prey relationships between. tiger sharks (Galeocerdo cuvier) and loggerhead turtles (Caretta caretta) in the North Atlantic Ocean. This included the use of satellite tracking to examine shark and turtle distributions as well as their surfacing behaviors under varying levels of home range overlap. Our findings revealed patterns that deviated from our a priori predictions based on the landscape of fear model. Specifically, turtles did not alter their surfacing behaviors to risk avoidance when overlap in shark-turtle core home range was high. However, in areas of high overlap with turtles, sharks exhibited modified surfacing behaviors that may enhance predation opportunity. We suggest that turtles may be an important factor in determining shark,distribution, whereas for turtles, other life history trade-offs may play a larger role in defining their habitat use. We propose that these findings are a result of both biotic and physically driven factors that independently or synergistically affect predator-prey interactions in this system. These results have implications for evolutionary biology, community ecology; and wildlife conservation. Further, given the difficulty in studying highly migratory marine species, our approach and conclusions may be applied to the study of other predator-prey systems.


Assuntos
Ecossistema , Medo , Comportamento Predatório/fisiologia , Tubarões/fisiologia , Tartarugas/fisiologia , Distribuição Animal , Animais , Oceano Atlântico , Reação de Fuga , Estações do Ano , Astronave , Telemetria
14.
Angew Chem Int Ed Engl ; 54(27): 7900-4, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26013580

RESUMO

Unlocking the full potential of rechargeable magnesium batteries has been partially hindered by the reliance on chloride-based complex systems. Despite the high anodic stability of these electrolytes, they are corrosive toward metallic battery components, which reduce their practical electrochemical window. Following on our new design concept involving boron cluster anions, monocarborane CB11H12(-) produced the first halogen-free, simple-type Mg salt that is compatible with Mg metal and displays an oxidative stability surpassing that of ether solvents. Owing to its inertness and non-corrosive nature, the Mg(CB11H12)2/tetraglyme (MMC/G4) electrolyte system permits standardized methods of high-voltage cathode testing that uses a typical coin cell. This achievement is a turning point in the research and development of Mg electrolytes that has deep implications on realizing practical rechargeable Mg batteries.

15.
Ann Surg ; 260(6): 1138-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25389925

RESUMO

OBJECTIVE: To investigate how epithelial mechanotransduction pathways impact wound repair. BACKGROUND: Mechanical forces are increasingly recognized to influence tissue repair, but their role in chronic wound pathophysiology remains unknown. Studies have shown that chronic wounds exhibit high levels of matrix metalloproteinase 9 (MMP9), a key proteolytic enzyme that regulates wound remodeling. We hypothesized that epithelial mechanosensory pathways regulated by keratinocyte-specific focal adhesion kinase (FAK) control dermal remodeling via MMP9. METHODS: A standard wound model was applied to keratinocyte-specific FAK knockout (KO) and control mice. Rates of wound healing were measured and tissue was obtained for histologic and molecular analyses. Transcriptional and immunoblot assays were used to assess the activation of FAK, intracellular kinases, and MMP9 in vitro. A cell suspension model was designed to validate the importance of FAK mechanosensing, p38, and MMP9 secretion in human cells. Biomechanical testing was utilized to evaluate matrix tensile properties in FAK KO and control wounds. RESULTS: Wound healing in FAK KO mice was significantly delayed compared with controls (closure at 15 days compared with 20 days, P = 0.0003). FAK KO wounds demonstrated decreased dermal thickness and collagen density. FAK KO keratinocytes exhibited overactive p38 and MMP9 signaling in vitro, findings recapitulated in human keratinocytes via the deactivation of FAK in the cell suspension model. Functionally, FAK KO wounds were significantly weaker and more brittle than control wounds, results consistent with the histologic and molecular analyses. CONCLUSIONS: Keratinocyte FAK is highly responsive to mechanical cues and may play a critical role in matrix remodeling via regulation of p38 and MMP9. These findings suggest that aberrant epithelial mechanosensory pathways may contribute to pathologic dermal proteolysis and wound chronicity.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/genética , Queratinócitos/ultraestrutura , RNA/genética , Pele/lesões , Regulação para Cima , Cicatrização , Ferimentos e Lesões/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Proteína-Tirosina Quinases de Adesão Focal/biossíntese , Humanos , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Recém-Nascido , Queratinócitos/metabolismo , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Proteólise , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
16.
Cancers (Basel) ; 16(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39001443

RESUMO

MM is a common type of cancer that unfortunately leads to a significant number of deaths each year. The majority of the reported MM cases are detected in the advanced stages, posing significant challenges for treatment. Additionally, all MM patients eventually develop resistance or experience relapse; therefore, advances in treatment are needed. However, developing new anti-cancer drugs, especially for MM, requires significant financial investment and a lengthy development process. The study of drug repurposing involves exploring the potential of existing drugs for new therapeutic uses. This can significantly reduce both time and costs, which are typically a major concern for MM patients. The utilization of pre-existing non-cancer drugs for various myeloma treatments presents a highly efficient and cost-effective strategy, considering their prior preclinical and clinical development. The drugs have shown promising potential in targeting key pathways associated with MM progression and resistance. Thalidomide exemplifies the success that can be achieved through this strategy. This review delves into the current trends, the challenges faced by conventional therapies for MM, and the importance of repurposing drugs for MM. This review highlights a noncomprehensive list of conventional therapies that have potentially significant anti-myeloma properties and anti-neoplastic effects. Additionally, we offer valuable insights into the resources that can help streamline and accelerate drug repurposing efforts in the field of MM.

17.
NPJ Microgravity ; 10(1): 46, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600142

RESUMO

A potential contribution to the progression of Spaceflight Associated Neuro-ocular Syndrome is the thoracic-to-spinal dural sac transmural pressure relationship. In this study, we utilize a lumped-parameter computational model of human cerebrospinal fluid (CSF) systems to investigate mechanisms of CSF redistribution. We present two analyses to illustrate potential mechanisms for CSF pressure alterations similar to those observed in microgravity conditions. Our numerical evidence suggests that the compliant relationship between thoracic and CSF compartments is insufficient to solely explain the observed decrease in CSF pressure with respect to the supine position. Our analyses suggest that the interaction between thoracic pressure and the cardiovascular system, particularly the central veins, has greater influence on CSF pressure. These results indicate that future studies should focus on the holistic system, with the impact of cardiovascular changes to the CSF pressure emphasized over the sequestration of fluid in the spine.

18.
JCI Insight ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39325545

RESUMO

Multiple sclerosis (MS) is a complex disease with significant heterogeneity in disease course and progression. Genetic studies have identified numerous loci associated with MS risk, but the genetic basis of disease progression remains elusive. To address this, we leveraged the Collaborative Cross (CC), a genetically diverse mouse strain panel, and experimental autoimmune encephalomyelitis (EAE). The thirty-two CC strains studied captured a wide spectrum of EAE severity, trajectory, and presentation, including severe-progressive, monophasic, relapsing remitting, and axial rotary (AR)-EAE, accompanied by distinct immunopathology. Sex differences in EAE severity were observed in six strains. Quantitative trait locus analysis revealed distinct genetic linkage patterns for different EAE phenotypes, including EAE severity and incidence of AR-EAE. Machine learning-based approaches prioritized candidate genes for loci underlying EAE severity (Abcc4 and Gpc6) and AR-EAE (Yap1 and Dync2h1). This work expands the EAE phenotypic repertoire and identifies novel loci controlling unique EAE phenotypes, supporting the hypothesis that heterogeneity in MS disease course is driven by genetic variation.

19.
Nat Commun ; 15(1): 2634, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528030

RESUMO

Real-time lab analysis is needed to support clinical decision making and research on human missions to the Moon and Mars. Powerful laboratory instruments, such as flow cytometers, are generally too cumbersome for spaceflight. Here, we show that scant test samples can be measured in microgravity, by a trained astronaut, using a miniature cytometry-based analyzer, the rHEALTH ONE, modified specifically for spaceflight. The base device addresses critical spaceflight requirements including minimal resource utilization and alignment-free optics for surviving rocket launch. To fully enable reduced gravity operation onboard the space station, we incorporated bubble-free fluidics, electromagnetic shielding, and gravity-independent sample introduction. We show microvolume flow cytometry from 10 µL sample drops, with data from five simultaneous channels using 10 µs bin intervals during each sample run, yielding an average of 72 million raw data points in approximately 2 min. We demonstrate the device measures each test sample repeatably, including correct identification of a sample that degraded in transit to the International Space Station. This approach can be utilized to further our understanding of spaceflight biology and provide immediate, actionable diagnostic information for management of astronaut health without the need for Earth-dependent analysis.


Assuntos
Voo Espacial , Ausência de Peso , Humanos , Citometria de Fluxo , Lua
20.
BMC Musculoskelet Disord ; 14: 20, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23311863

RESUMO

BACKGROUND: Proper blood pressure control during surgical procedures such as total joint arthroplasty (TJA) is considered critical to good outcome. There is poor understanding of the pre-operative risk factors for poor intra-operative hemodynamic control. The purpose of this study is to identify risk factors for poor hemodynamic control during TJA. METHODS: We performed a retrospective cohort analysis of 118 patients receiving TJA in the Dominican Republic. We collected patient demographic and comorbidity data. We developed an a priori definition for poor hemodynamic control: 1) Mean arterial pressure (MAP) <65% of preoperative MAP or 2) MAP >135% of preoperative MAP. We performed bivariate and multivariate analyses to identify risk factors for poor hemodynamic control during TJA. RESULTS: Hypertension was relatively common in our study population (76 of 118 patients). Average preoperative mean arterial pressure was 109.0 (corresponding to an average SBP of 149 and DBP of 89). Forty-nine (41.5%) patients had intraoperative blood pressure readings consistent with poor hemodynamic control. Based on multi-variable analysis preoperative hypertension of any type (RR 2.9; 95% CI 1.3-6.3) and an increase in BMI (RR 1.2 per 5 unit increase; 95% CI 1.0-1.5) were significant risk factors for poor hemodynamic control. CONCLUSIONS: Preoperative hypertension and being overweight/obese increase the likelihood of poor blood pressure control during TJA. Hypertensive and/or obese patients warrant further attention and medical optimization prior to TJA. More work is required to elucidate the relationship between these risk factors and overall outcome.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Hemodinâmica , Hipertensão/complicações , Artropatias/cirurgia , Obesidade/complicações , Pressão Arterial , Índice de Massa Corporal , Comorbidade , República Dominicana , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Artropatias/complicações , Artropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/diagnóstico , Obesidade/fisiopatologia , Razão de Chances , Estudos Retrospectivos , Fatores de Risco
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