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1.
Nature ; 583(7816): 411-414, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32555453

RESUMEN

Egg size and structure reflect important constraints on the reproductive and life-history characteristics of vertebrates1. More than two-thirds of all extant amniotes lay eggs2. During the Mesozoic era (around 250 million to 65 million years ago), body sizes reached extremes; nevertheless, the largest known egg belongs to the only recently extinct elephant bird3, which was roughly 66 million years younger than the last nonavian dinosaurs and giant marine reptiles. Here we report a new type of egg discovered in nearshore marine deposits from the Late Cretaceous period (roughly 68 million years ago) of Antarctica. It exceeds all nonavian dinosaur eggs in volume and differs from them in structure. Although the elephant bird egg is slightly larger, its eggshell is roughly five times thicker and shows a substantial prismatic layer and complex pore structure4. By contrast, the new fossil, visibly collapsed and folded, presents a thin eggshell with a layered structure that lacks a prismatic layer and distinct pores, and is similar to that of most extant lizards and snakes (Lepidosauria)5. The identity of the animal that laid the egg is unknown, but these preserved morphologies are consistent with the skeletal remains of mosasaurs (large marine lepidosaurs) found nearby. They are not consistent with described morphologies of dinosaur eggs of a similar size class. Phylogenetic analyses of traits for 259 lepidosaur species plus outgroups suggest that the egg belonged to an individual that was at least 7 metres long, hypothesized to be a giant marine reptile, all clades of which have previously been proposed to show live birth6. Such a large egg with a relatively thin eggshell may reflect derived constraints associated with body shape, reproductive investment linked with gigantism, and lepidosaurian viviparity, in which a 'vestigial' egg is laid and hatches immediately7.


Asunto(s)
Dinosaurios , Cáscara de Huevo/anatomía & histología , Cáscara de Huevo/química , Fósiles , Dureza , Animales , Evolución Biológica , Dinosaurios/clasificación
2.
Proc Natl Acad Sci U S A ; 120(11): e2219523120, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36893269

RESUMEN

The continuous evolution of SARS-CoV-2 variants complicates efforts to combat the ongoing pandemic, underscoring the need for a dynamic platform for the rapid development of pan-viral variant therapeutics. Oligonucleotide therapeutics are enhancing the treatment of numerous diseases with unprecedented potency, duration of effect, and safety. Through the systematic screening of hundreds of oligonucleotide sequences, we identified fully chemically stabilized siRNAs and ASOs that target regions of the SARS-CoV-2 genome conserved in all variants of concern, including delta and omicron. We successively evaluated candidates in cellular reporter assays, followed by viral inhibition in cell culture, with eventual testing of leads for in vivo antiviral activity in the lung. Previous attempts to deliver therapeutic oligonucleotides to the lung have met with only modest success. Here, we report the development of a platform for identifying and generating potent, chemically modified multimeric siRNAs bioavailable in the lung after local intranasal and intratracheal delivery. The optimized divalent siRNAs showed robust antiviral activity in human cells and mouse models of SARS-CoV-2 infection and represent a new paradigm for antiviral therapeutic development for current and future pandemics.


Asunto(s)
COVID-19 , Humanos , Animales , Ratones , ARN Interferente Pequeño/genética , COVID-19/terapia , SARS-CoV-2/genética , Antivirales/farmacología , Antivirales/uso terapéutico , Oligonucleótidos , Pulmón
3.
Invest New Drugs ; 42(1): 127-135, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38270822

RESUMEN

Navitoclax (ABT-263) is an oral BCL2 homology-3 mimetic that binds with high affinity to pro-survival BCL2 proteins, resulting in apoptosis. Sorafenib, an oral multi kinase inhibitor also promotes apoptosis and inhibits tumor angiogenesis. The efficacy of either agent alone is limited; however, preclinical studies demonstrate synergy with the combination of navitoclax and sorafenib. In this phase 1 study, we evaluated the combination of navitoclax and sorafenib in a dose escalation cohort of patients with refractory solid tumors, with an expansion cohort in hepatocellular carcinoma (HCC). Maximum tolerated dose (MTD) was determined using the continual reassessment method. Navitoclax and sorafenib were administered continuously on days 1 through 21 of 21-day cycles. Ten patients were enrolled in the dose escalation cohort and 15 HCC patients were enrolled in the expansion cohort. Two dose levels were tested, and the MTD was navitoclax 150 mg daily plus sorafenib 400 mg twice daily. Among all patients, the most common grade 3 toxicity was thrombocytopenia (5 patients, 20%): there were no grade 4 or 5 toxicities. Patients received a median of 2 cycles (range 1-36 cycles) and all patients were off study treatment at data cut off. Six patients in the expansion cohort had stable disease, and there were no partial or complete responses. Drug-drug interaction between navitoclax and sorafenib was not observed. The combination of navitoclax and sorafenib did not increase induction of apoptosis compared with navitoclax alone. Navitoclax plus sorafenib is tolerable but showed limited efficacy in the HCC expansion cohort. These findings do not support further development of this combination for the treatment of advanced HCC. This phase I trial was conducted under ClinicalTrials.gov registry number NCT01364051.


Asunto(s)
Compuestos de Anilina , Carcinoma Hepatocelular , Neoplasias Hepáticas , Sorafenib , Humanos , Compuestos de Anilina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Sorafenib/uso terapéutico , Sulfonamidas/uso terapéutico
4.
Sol Phys ; 299(6): 78, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38867765

RESUMEN

We present the design of a portable coronagraph, CATEcor (where CATE stands for Continental-America Telescope Eclipse), that incorporates a novel "shaded-truss" style of external occultation and serves as a proof-of-concept for that family of coronagraphs. The shaded-truss design style has the potential for broad application in various scientific settings. We conceived CATEcor itself as a simple instrument to observe the corona during the darker skies available during a partial solar eclipse, or for students or interested amateurs to detect the corona under ideal noneclipsed conditions. CATEcor is therefore optimized for simplicity and accessibility to the public. It is implemented using an existing dioptric telescope and an adapter rig that mounts in front of the objective lens, restricting the telescope aperture and providing external occultation. The adapter rig, including occulter, is fabricated using fusion deposition modeling (FDM; colloquially "3D printing"), greatly reducing cost. The structure is designed to be integrated with moderate care and may be replicated in a university or amateur setting. While CATEcor is a simple demonstration unit, the design concept, process, and trades are useful for other more sophisticated coronagraphs in the same general family, which might operate under normal daytime skies outside the annular-eclipse conditions used for CATEcor.

5.
J Pharmacol Exp Ther ; 384(2): 306-314, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36456195

RESUMEN

Development of neurocognitive disorder in human immunodeficiency virus (HIV)-infected patients has been linked to dysregulation of dopamine by the HIV-1 transactivator of transcription (Tat) protein, a negative allosteric modulator of dopamine transporter (DAT). Using fast scan cyclic voltammetry, the present study determined the effects of in vivo Tat expression on dopamine release in the caudate putamen of inducible Tat transgenic (iTat-tg) mice and the impact of a novel DAT allosteric modulator, Southern Research Institute (SRI)-32743, on the Tat effect. We found that 7- or 14-day doxycycline (Dox)-induced Tat expression in iTat-tg mice resulted in a 2-fold increase in phasic but not tonic stimulated baseline dopamine release relative to saline control mice. To determine whether the Tat-induced increase in dopamine release is mediated by DAT regulation, we examined the effect of an in vitro applied DAT inhibitor, nomifensine, on the dopamine release. Nomifensine (1 nM-10 µM) concentration-dependently enhanced phasic stimulated dopamine release in both saline- and Dox-treated iTat-tg mice, while the magnitude of the nomifensine-mediated dopamine release was unchanged between saline and Dox treatment groups. A single systemic administration of SRI-32743 prior to animal sacrifice reversed the increased dopamine release in the baseline of phasic dopamine release and nomifensine-augmented dopamine levels in Dox-treated iTat-tg mice, while SRI-32743 alone did not alter baseline of dopamine release. These findings suggest that Tat expression induced an increase in extracellular dopamine levels by not only inhibiting DAT-mediated dopamine transport but also stimulating synaptic dopamine release. Thus, DAT allosteric modulators may serve as a potential therapeutic intervention for HIV infection-dysregulated dopamine system observed in HIV-1 positive individuals. SIGNIFICANCE STATEMENT: HIV infection-induced dysregulation of the dopaminergic system has been implicated in the development of neurocognitive impairments observed in HIV positive patients. Understanding the mechanisms underlying HIV-1 Tat protein-induced alteration of extracellular dopamine levels will provide insights into the development of molecules that can attenuate Tat interaction with targets in the dopaminergic system. Here, we determined whether Tat alters dopamine release and how the novel DAT allosteric modulator, SRI-32743, impacts dopamine neurotransmission to attenuate Tat-induced effects on extracellular dopamine dynamics.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Ratones , Animales , Ratones Transgénicos , VIH-1/metabolismo , Dopamina/metabolismo , Transactivadores/metabolismo , Nomifensina/metabolismo , Putamen/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana
6.
Osteoporos Int ; 34(10): 1711-1718, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37294333

RESUMEN

PURPOSE: Worldwide, many people who would benefit from osteoporosis drugs are not offered or receiving them, resulting in an osteoporosis care gap. Adherence with bisphosphonates is particularly low. This study aimed to identify stakeholder research priorities relating to bisphosphonate treatment regimens for prevention of osteoporotic fractures. METHODS: A three-step approach based on the James Lind Alliance methodology for identification and prioritisation of research questions was used. Research uncertainties were gathered from a large programme of related research studies about bisphosphonate regimens and from recent published international clinical guidelines. Clinical and public stakeholders refined the list of uncertainties into research questions. The third step prioritised the questions using a modified nominal group technique. RESULTS: In total, 34 draft uncertainties were finalised into 33 research questions by stakeholders. The top 10 includes questions relating to which people should be offered intravenous bisphosphonates first line (1); optimal duration of treatment (2); the role of bone turnover markers in treatment breaks (3); support patient need for medicine optimisation (4); support primary care practitioner need regarding bisphosphonates (5); comparing zoledronate given in community vs hospital settings (6); ensuring quality standards are met (7); the long-term model of care (8); best bisphosphonate for people aged under 50 (9); and supporting patient decision-making about bisphosphonates (10). CONCLUSION: This study reports, for the first time, topics of importance to stakeholders in the research of bisphosphonate osteoporosis treatment regimens. These findings have implications for research into implementation to address the care gap and education of healthcare professionals. Using James Lind Alliance methodology, this study reports prioritised topics of importance to stakeholders in the research of bisphosphonate treatment in osteoporosis. The priorities address how to better implement guidelines to address the care gap, understanding patient factors influencing treatment selection and effectiveness, and how to optimise long-term care.


Asunto(s)
Investigación Biomédica , Osteoporosis , Humanos , Anciano , Difosfonatos/uso terapéutico , Osteoporosis/tratamiento farmacológico , Selección de Paciente , Reino Unido
7.
Ann Bot ; 132(4): 819-833, 2023 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-37279950

RESUMEN

BACKGROUND AND SCOPE: Crassulacean acid metabolism (CAM) is an intriguing physiological adaptation in plants that are widespread throughout many ecosystems. Despite the relatively recent mechanistic understanding of CAM in plant physiology, evidence from historical records suggests that ancient cultures in the Americas also recognized the value of CAM plants. Agave species, in particular, have a rich cultural legacy that provides a foundation for commercially valued products. Here, we review that legacy and potential relationships between ancient values and the needs of modern-day climate adaptation strategies. CONCLUSIONS: There are many products that can be produced from Agave species, including food, sugar, fibre and medicines. Traditional knowledge about agricultural management and preparation of plant products can be combined with new ecophysiological knowledge and agronomic techniques to develop these resources in the borderland region of the southwestern USA and Mexico. Historical records of pre-Columbian practices in the Sonoran desert and remnants of centuries-old agriculture in Baja California and Sonora demonstrate the climate resilience of Agave agriculture. Commercial growth of both tequila and bacanora indicates the potential for large-scale production today, but also underscores the importance of adopting regenerative agricultural practices to accomplish environmentally sustainable production. Recent international recognition of the Appellation of Origin for several Agave species produced for spirits in Mexico might provide opportunities for agricultural diversification. In contrast, fibre is currently produced from several Agave species on many continents. Projections of growth with future climate change suggest that Agave spp. will be viable alternatives for commodity crops that suffer declines during drought and increased temperatures. Historical cultivation of Agave affirms that these CAM plants can supply sugar, soft and hard fibres, medicines and food supplements.


Asunto(s)
Agave , Metabolismo Ácido de las Crasuláceas , Agave/metabolismo , Ecosistema , México , Azúcares/metabolismo
8.
Ann Fam Med ; 21(1): 46-53, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36690495

RESUMEN

PURPOSE: Most patients are escorted to exam rooms (escorted rooming) although patients directing themselves to their exam room (self-rooming) saves patient and staff time while increasing patient satisfaction. This study assesses patient and staff perceptions after pragmatic implementation of self-rooming. METHODS: In October-December 2020, we surveyed patients and staff in 25 primary care clinics after our institution expanded self-rooming from 4 specially built clinics during the COVID-19 pandemic. Semi-structured surveys asked about rooming process used, rooming process preferred, and perceptions of self-rooming compared with escorted rooming. RESULTS: Most patients (n = 1,561) preferred self-rooming (86%), especially among patients aged <65 years and in family medicine clinics. Few patients felt less welcomed (10.6%), less cared about (6.8%), more isolated (15.6%), more lost/confused (7.6%), or more frustrated (3.2%) with self-rooming compared with escorted rooming. Early-adopter clinics that implemented self-rooming ≤2016 had even lower rates of patients feeling more isolated, lost/confused, or frustrated with self-rooming compared with escorted rooming.Over one-half of staff (n = 241; 180 clinical, 61 nonclinical) preferred self-rooming (59%) and thought most patients liked self-rooming (65.8%), especially among clinical staff and in early adopter clinics (≤2016). Few staff reported worse waiting times for patients (12.4%), medical assistants (MAs) (15.9%), and clinicians (16.4%) or worse crowding in waiting areas (1.7%) and hallways (10.1%). Unlike patient-reported confusion (7.6%), most staff thought self-rooming led to more patient confusion (63.8%), except in early-adopter clinics (44.4%). CONCLUSIONS: Self-rooming is a patient-centered innovation that is also acceptable to staff. We demonstrated that pragmatic implementation is feasible across primary care without expensive technology or specially designed buildings.


Asunto(s)
COVID-19 , Salas de Espera , Humanos , Pandemias , Instituciones de Atención Ambulatoria , Atención Primaria de Salud
9.
Nucleic Acids Res ; 49(21): 12069-12088, 2021 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-34850120

RESUMEN

Oligonucleotides is an emerging class of chemically-distinct therapeutic modalities, where extensive chemical modifications are fundamental for their clinical applications. Inter-nucleotide backbones are critical to the behaviour of therapeutic oligonucleotides, but clinically explored backbone analogues are, effectively, limited to phosphorothioates. Here, we describe the synthesis and bio-functional characterization of an internucleotide (E)-vinylphosphonate (iE-VP) backbone, where bridging oxygen is substituted with carbon in a locked stereo-conformation. After optimizing synthetic pathways for iE-VP-linked dimer phosphoramidites in different sugar contexts, we systematically evaluated the impact of the iE-VP backbone on oligonucleotide interactions with a variety of cellular proteins. Furthermore, we systematically evaluated the impact of iE-VP on RNA-Induced Silencing Complex (RISC) activity, where backbone stereo-constraining has profound position-specific effects. Using Huntingtin (HTT) gene causative of Huntington's disease as an example, iE-VP at position 6 significantly enhanced the single mismatch discrimination ability of the RISC without negative impact on silencing of targeting wild type htt gene. These findings suggest that the iE-VP backbone can be used to modulate the activity and specificity of RISC. Our study provides (i) a new chemical tool to alter oligonucleotide-enzyme interactions and metabolic stability, (ii) insight into RISC dynamics and (iii) a new strategy for highly selective SNP-discriminating siRNAs.


Asunto(s)
Enfermedad de Huntington/genética , Oligonucleótidos/metabolismo , ARN Interferente Pequeño/metabolismo , Alelos , Humanos , Organofosfonatos
10.
Int J Behav Med ; 30(5): 585-604, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36284042

RESUMEN

BACKGROUND: People with advanced cancer experience psychological distress due to physical symptoms, functional decline, and a limited prognosis. Difficult thoughts, feelings, and emotions may exacerbate distress and lead to avoidance of these experiences which is sometimes referred to as experiential avoidance (EA). Advanced cancer patients may be more likely to engage in EA especially when no obvious solutions to their problems exist. This study aims to examine the terms used to describe EA, the processes that might indicate EA, associations between EA and psychological distress, and to understand why individuals might engage in EA. METHODS: A mixed-methods review. Literature search of Medline, Embase, Psych INFO, and CINAHL 1980-October 2019. INCLUSION: adults ≥ 18 years; advanced cancer not amenable to cure. EXCLUSION: no measures of EA or psychological distress. Risk of bias and study quality assessed. Evidence of statistical techniques collected. Themes coded, grouped, and developed based on meaning. RESULTS: Nineteen studies identified, 13 quantitative studies and 6 qualitative. The quantitative of which 6 compared early-stage cancers with advanced cancers and examined subscales of EA alongside mood, quality of life, and psychological distress. EA covers a range or terms of which 'avoidant coping' is the commonest. EA is manifest as cognitive, behavioural, and emotional avoidance. A thematic synthesis suggests the function of EA is to protect people from distress, and from confronting or expressing difficult emotions by avoiding communication about cancer, controlling negative information, and maintaining normality and hope and optimism. CONCLUSIONS: EA may be beneficial in the short term to alleviate distress, but in the longer term, it can impair function and limit engagement in life. Greater clinical awareness of the complexity of EA behaviours is needed. Clinicians and researchers should define EA precisely and be aware of the function it may serve in the short and longer term. Future research studies may consider using specific measures of EA as a primary outcome, to assess the impact of psychological interventions such as ACT.


Asunto(s)
Neoplasias , Estrés Psicológico , Adulto , Humanos , Estrés Psicológico/psicología , Calidad de Vida/psicología , Emociones , Afecto , Neoplasias/psicología
11.
Pediatr Cardiol ; 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37209186

RESUMEN

Enteral feeds are often withheld from neonates with ductal dependent cardiac lesions who are receiving prostaglandins. This is despite positive benefits of enteral feeding. We describe a multicenter cohort of these neonates who were fed pre-operatively. We also give a granular description of vital sign measurements and other risk factors prior to feeding. A retrospective chart review was performed at seven centers. Inclusion criteria were full-term neonates under one month of age with ductal dependent lesions receiving prostaglandins. These neonates were fed for at least 24 h during the pre-operative period. Premature neonates were excluded. Using the inclusion criteria, 127 neonates were identified. While being fed, 20.5% of the neonates were intubated, 10.2% were on inotropes, and 55.9% had an umbilical arterial catheter in place. Median oxygen saturations in the six hours prior to feeding were 92.5% in patients with cyanotic lesions, median diastolic blood pressure was 38 mmHg and median somatic NIRS were 66.5%. The median peak daily feeding volume reached was 29 ml/kg/day (IQ range 15.5-96.8 ml/kg/day). One patient developed suspected necrotizing enterocolitis (NEC) in this cohort. Only one adverse event occurred, which was an aspiration thought to be related to feeding, but did not result in intubation or cessation of feeds. NEC was rare among neonates with ductal dependent lesions while receiving enteral nutrition pre-operatively. Umbilical arterial catheters were in place in the majority of these patients. Hemodynamic measures demonstrated a high median oxygen saturation prior to initiation of feeds.

12.
Int J Mol Sci ; 24(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37895020

RESUMEN

Neurodegenerative diseases affect millions of people worldwide. Neurodegenerative diseases result from progressive damage to nerve cells in the brain or peripheral nervous system connections that are essential for cognition, coordination, strength, sensation, and mobility. Dysfunction of these brain and nerve functions is associated with Alzheimer's disease, Parkinson's disease, Huntington's disease, Amyotrophic lateral sclerosis, and motor neuron disease. In addition to these, 50% of people living with HIV develop a spectrum of cognitive, motor, and/or mood problems collectively referred to as HIV-Associated Neurocognitive Disorders (HAND) despite the widespread use of a combination of antiretroviral therapies. Neuroinflammation and neurotransmitter systems have a pathological correlation and play a critical role in developing neurodegenerative diseases. Each of these diseases has a unique pattern of dysregulation of the neurotransmitter system, which has been attributed to different forms of cell-specific neuronal loss. In this review, we will focus on a discussion of the regulation of dopaminergic and cholinergic systems, which are more commonly disturbed in neurodegenerative disorders. Additionally, we will provide evidence for the hypothesis that disturbances in neurotransmission contribute to the neuronal loss observed in neurodegenerative disorders. Further, we will highlight the critical role of dopamine as a mediator of neuronal injury and loss in the context of NeuroHIV. This review will highlight the need to further investigate neurotransmission systems for their role in the etiology of neurodegenerative disorders.


Asunto(s)
Enfermedad de Alzheimer , Infecciones por VIH , Enfermedad de Huntington , Enfermedades Neurodegenerativas , Humanos , Enfermedades Neurodegenerativas/patología , Enfermedad de Alzheimer/patología , Encéfalo/patología , Enfermedad de Huntington/patología , Infecciones por VIH/patología
13.
J Public Health Manag Pract ; 29(2): 202-209, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36214660

RESUMEN

CONTEXT: There have been multiple calls in the United States for public health workforce development approaches that expand practitioner skill sets to respond to profound inequities and improve population health more effectively. However, most workforce models address individual competencies that instead focus on collective approaches to systems change. PROGRAM: In response to this opportunity, the HRSA-funded Regional Public Health Training Centers (PHTCs) and the University of Illinois Chicago Policy, Practice, and Prevention Research Center (P3RC) released Creating a Learning Agenda for Systems Change: A Toolkit for Building an Adaptive Public Health Workforce (the Toolkit) in December 2020. We later supplemented the Toolkit with additional learning activities to launch the Learning Agenda Toolkit Pilot Test (Toolkit Pilot). IMPLEMENTATION: From June to August 2021, 24 diverse teams piloted the Toolkit. Teams completed a multistep process simulating the development of a learning agenda aimed at addressing community health issues and impacting systems change. EVALUATION: We conducted an evaluation process to assess the usability and impact of the Toolkit Pilot to inform its improvement and future implementation. An evaluation subcommittee analyzed worksheets completed by the Pilot Teams that are aligned to the Learning Agenda steps and conducted and analyzed 12 key informant interviews using concepts from the Toolkit Pilot Logic Model. FINDINGS AND DISCUSSION: Evaluation results suggest that most Pilot Teams found that the Toolkit Pilot offered a step-by-step process toward a clear vision that produced a concrete product on how to address community challenges through learning and systems change. Pilot Teams noted that the Toolkit Pilot provided exposure to and a unique focus on systems thinking; however, prior knowledge of systems thinking and systems change was important. Building readiness for systems change and having more time, resources, and technical assistance would be needed for future versions of the Learning Agenda Toolkit.


Asunto(s)
Investigación sobre Servicios de Salud , Salud Pública , Humanos , Estados Unidos , Proyectos Piloto , Recursos Humanos , Educación en Salud
14.
Clin Infect Dis ; 74(5): 802-811, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-34145450

RESUMEN

BACKGROUND: The COVID-19 pandemic has resulted in unprecedented healthcare challenges, and COVID-19 has been linked to secondary infections. Candidemia, a fungal healthcare-associated infection, has been described in patients hospitalized with severe COVID-19. However, studies of candidemia and COVID-19 coinfection have been limited in sample size and geographic scope. We assessed differences in patients with candidemia with and without a COVID-19 diagnosis. METHODS: We conducted a case-level analysis using population-based candidemia surveillance data collected through the Centers for Disease Control and Prevention's Emerging Infections Program during April-August 2020 to compare characteristics of candidemia patients with and without a positive test for COVID-19 in the 30 days before their Candida culture using chi-square or Fisher's exact tests. RESULTS: Of the 251 candidemia patients included, 64 (25.5%) were positive for SARS-CoV-2. Liver disease, solid-organ malignancies, and prior surgeries were each >3 times more common in patients without COVID-19 coinfection, whereas intensive care unit-level care, mechanical ventilation, having a central venous catheter, and receipt of corticosteroids and immunosuppressants were each >1.3 times more common in patients with COVID-19. All-cause in-hospital fatality was 2 times higher among those with COVID-19 (62.5%) than without (32.1%). CONCLUSIONS: One-quarter of candidemia patients had COVID-19. These patients were less likely to have certain underlying conditions and recent surgery commonly associated with candidemia and more likely to have acute risk factors linked to COVID-19 care, including immunosuppressive medications. Given the high mortality, it is important for clinicians to remain vigilant and take proactive measures to prevent candidemia in patients with COVID-19.


Asunto(s)
COVID-19 , Candidemia , COVID-19/epidemiología , Prueba de COVID-19 , Candidemia/tratamiento farmacológico , Humanos , Pandemias , SARS-CoV-2
15.
Emerg Infect Dis ; 28(1): 95-103, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34856114

RESUMEN

To determine risk factors for coronavirus disease (COVID-19) among US healthcare personnel (HCP), we conducted a case-control analysis. We collected data about activities outside the workplace and COVID-19 patient care activities from HCP with positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test results (cases) and from HCP with negative test results (controls) in healthcare facilities in 5 US states. We used conditional logistic regression to calculate adjusted matched odds ratios and 95% CIs for exposures. Among 345 cases and 622 controls, factors associated with risk were having close contact with persons with COVID-19 outside the workplace, having close contact with COVID-19 patients in the workplace, and assisting COVID-19 patients with activities of daily living. Protecting HCP from COVID-19 may require interventions that reduce their exposures outside the workplace and improve their ability to more safely assist COVID-19 patients with activities of daily living.


Asunto(s)
COVID-19 , Exposición Profesional , Actividades Cotidianas , Atención a la Salud , Personal de Salud , Humanos , Factores de Riesgo , SARS-CoV-2
16.
Age Ageing ; 51(3)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35284926

RESUMEN

BACKGROUND: osteoporotic vertebral fractures (OVFs) identify people at high risk of future fractures, but despite this, less than a third come to clinical attention. The objective of this study was to develop a clinical tool to aid health care professionals decide which older women with back pain should have a spinal radiograph. METHODS: a population-based cohort of 1,635 women aged 65+ years with self-reported back pain in the previous 4 months were recruited from primary care. Exposure data were collected through self-completion questionnaires and physical examination, including descriptions of back pain and traditional risk factors for osteoporosis. Outcome was the presence/absence of OVFs on spinal radiographs. Logistic regression models identified independent predictors of OVFs, with the area under the (receiver operating) curve calculated for the final model, and a cut-point was identified. RESULTS: mean age was 73.9 years and 209 (12.8%) had OVFs. The final Vfrac model comprised 15 predictors of OVF, with an AUC of 0.802 (95% CI: 0.764-0.840). Sensitivity was 72.4% and specificity was 72.9%. Vfrac identified 93% of those with more than one OVF and two-thirds of those with one OVF. Performance was enhanced by inclusion of self-reported back pain descriptors, removal of which reduced AUC to 0.742 (95% CI: 0.696-0.788) and sensitivity to 66.5%. Health economic modelling to support a future trial was favourable. CONCLUSIONS: the Vfrac clinical tool appears to be valid and is improved by the addition of self-reported back pain symptoms. The tool now requires testing to establish real-world clinical and cost-effectiveness.


Asunto(s)
Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Anciano , Dolor de Espalda/diagnóstico , Dolor de Espalda/epidemiología , Dolor de Espalda/etiología , Estudios de Cohortes , Análisis Costo-Beneficio , Femenino , Humanos , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología
17.
Intern Med J ; 52(10): 1773-1779, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34580977

RESUMEN

BACKGROUND: Renal resistive index (RRI), which reflects intrarenal arterial impedance, is routinely measured when undertaking renal Doppler ultrasonography (RDU). Increased RRI has been suggested to reflect renal parenchymal disease and imply risk of kidney disease progression. But this has been disputed and extra-renal haemodynamic factors rather than intra-renal factors have been proposed to determine RRI. AIMS: To investigate the relationship between elevated RRI and presence of chronic kidney disease (CKD), and examine whether elevated RRI at baseline is associated with decline in estimated glomerular filtration rate (eGFR) on follow up. METHODS: This retrospective observational study examined the association of elevated RRI (>0.7) with the presence of CKD (eGFR < 60 mL/min for >3 months), demographic and clinical factors in multivariable models. We also examined the effect of elevated RRI on eGFR decline on follow up using mixed models. RESULTS: Of the 346 patients undergoing RDU (median age 69.7 years; 46.2% male), 180 had elevated RRI. There was a strong inverse association between RRI and eGFR at baseline, 1 and 2 years (rho = -0.53, -0.51, -0.53, all P < 001). Elevated RRI was independently predicted by older age (odds ratio 3.29; 95% confidence interval 2.25-4.8; P < 0.001) and diabetes (odds ratio 2.65; 95% confidence interval 1.21-5.80; P = 0.015), but not CKD using multivariate logistic regression. Decline of eGFR was not different between RRI categories on follow up. CONCLUSION: Elevated RRI was predicted by older age and diabetes, but not by the presence of CKD. Baseline RRI was not associated with eGFR decline.


Asunto(s)
Riñón , Insuficiencia Renal Crónica , Humanos , Masculino , Anciano , Femenino , Estudios Retrospectivos , Riñón/diagnóstico por imagen , Insuficiencia Renal Crónica/diagnóstico por imagen , Insuficiencia Renal Crónica/epidemiología , Tasa de Filtración Glomerular , Ultrasonografía
18.
Nucleic Acids Res ; 48(14): 7665-7680, 2020 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-32672813

RESUMEN

Small interfering RNAs (siRNAs) have revolutionized the treatment of liver diseases. However, robust siRNA delivery to other tissues represents a major technological need. Conjugating lipids (e.g. docosanoic acid, DCA) to siRNA supports extrahepatic delivery, but tissue accumulation and gene silencing efficacy are lower than that achieved in liver by clinical-stage compounds. The chemical structure of conjugated siRNA may significantly impact invivo efficacy, particularly in tissues with lower compound accumulation. Here, we report the first systematic evaluation of the impact of siRNA scaffold-i.e. structure, phosphorothioate (PS) content, linker composition-on DCA-conjugated siRNA delivery and efficacy in vivo. We found that structural asymmetry (e.g. 5- or 2-nt overhang) has no impact on accumulation, but is a principal factor for enhancing activity in extrahepatic tissues. Similarly, linker chemistry (cleavable versus stable) altered activity, but not accumulation. In contrast, increasing PS content enhanced accumulation of asymmetric compounds, but negatively impacted efficacy. Our findings suggest that siRNA tissue accumulation does not fully define efficacy, and that the impact of siRNA chemical structure on activity is driven by intracellular re-distribution and endosomal escape. Fine-tuning siRNA chemical structure for optimal extrahepatic efficacy is a critical next step for the progression of therapeutic RNAi applications beyond liver.


Asunto(s)
Oligonucleótidos Fosforotioatos/química , ARN Interferente Pequeño/química , ARN Interferente Pequeño/farmacocinética , Animales , Femenino , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Interferencia de ARN , Distribución Tisular
19.
PLoS Genet ; 15(1): e1007892, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30703081

RESUMEN

Candida albicans is among the most common causes of human fungal infections and is an important source of mortality. C. albicans is able to diminish its detection by innate immune cells through masking of ß (1,3)-glucan in the inner cell wall with an outer layer of heavily glycosylated mannoproteins (mannan). However, mutations or drugs that disrupt the cell wall can lead to exposure of ß (1,3)-glucan (unmasking) and enhanced detection by innate immune cells through receptors like Dectin-1, the C-type signaling lectin. Previously, our lab showed that the pathway for synthesizing the phospholipid phosphatidylserine (PS) plays a role in ß (1,3)-glucan masking. The homozygous PS synthase knockout mutant, cho1Δ/Δ, exhibits increased exposure of ß (1,3)-glucan. Several Mitogen Activated Protein Kinase (MAPK) pathways and their upstream Rho-type small GTPases are important for regulating cell wall biogenesis and remodeling. In the cho1Δ/Δ mutant, both the Cek1 and Mkc1 MAPKs are constitutively activated, and they act downstream of the small GTPases Cdc42 and Rho1, respectively. In addition, Cdc42 activity is up-regulated in cho1Δ/Δ. Thus, it was hypothesized that activation of Cdc42 or Rho1 and their downstream kinases cause unmasking. Disruption of MKC1 does not decrease unmasking in cho1Δ/Δ, and hyperactivation of Rho1 in wild-type cells increases unmasking and activation of both Cek1 and Mkc1. Moreover, independent hyperactivation of the MAP kinase kinase kinase Ste11 in wild-type cells leads to Cek1 activation and increased ß (1,3)-glucan exposure. Thus, upregulation of the Cek1 MAPK pathway causes unmasking, and may be responsible for unmasking in cho1Δ/Δ.


Asunto(s)
CDPdiacilglicerol-Serina O-Fosfatidiltransferasa/genética , Candida albicans/genética , Proteínas Fúngicas/genética , Quinasas Quinasa Quinasa PAM/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Pared Celular/genética , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Regulación Fúngica de la Expresión Génica , Técnicas de Inactivación de Genes , Guanosina Trifosfato/genética , Humanos , Lectinas Tipo C/genética , Sistema de Señalización de MAP Quinasas/genética , Proteínas Quinasas Activadas por Mitógenos/genética , beta-Glucanos/química , beta-Glucanos/metabolismo , Proteína de Unión al GTP cdc42/genética
20.
Ann Intern Med ; 174(10): 1409-1419, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34370517

RESUMEN

BACKGROUND: The COVID-19 pandemic has caused substantial morbidity and mortality. OBJECTIVE: To describe monthly clinical trends among adults hospitalized with COVID-19. DESIGN: Pooled cross-sectional study. SETTING: 99 counties in 14 states participating in the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET). PATIENTS: U.S. adults (aged ≥18 years) hospitalized with laboratory-confirmed COVID-19 during 1 March to 31 December 2020. MEASUREMENTS: Monthly hospitalizations, intensive care unit (ICU) admissions, and in-hospital death rates per 100 000 persons in the population; monthly trends in weighted percentages of interventions, including ICU admission, mechanical ventilation, and vasopressor use, among an age- and site-stratified random sample of hospitalized case patients. RESULTS: Among 116 743 hospitalized adults with COVID-19, the median age was 62 years, 50.7% were male, and 40.8% were non-Hispanic White. Monthly rates of hospitalization (105.3 per 100 000 persons), ICU admission (20.2 per 100 000 persons), and death (11.7 per 100 000 persons) peaked during December 2020. Rates of all 3 outcomes were highest among adults aged 65 years or older, males, and Hispanic or non-Hispanic Black persons. Among 18 508 sampled hospitalized adults, use of remdesivir and systemic corticosteroids increased from 1.7% and 18.9%, respectively, in March to 53.8% and 74.2%, respectively, in December. Frequency of ICU admission, mechanical ventilation, and vasopressor use decreased from March (37.8%, 27.8%, and 22.7%, respectively) to December (20.5%, 12.3%, and 12.8%, respectively); use of noninvasive respiratory support increased from March to December. LIMITATION: COVID-NET covers approximately 10% of the U.S. population; findings may not be generalizable to the entire country. CONCLUSION: Rates of COVID-19-associated hospitalization, ICU admission, and death were highest in December 2020, corresponding with the third peak of the U.S. pandemic. The frequency of intensive interventions for management of hospitalized patients decreased over time. These data provide a longitudinal assessment of clinical trends among adults hospitalized with COVID-19 before widespread implementation of COVID-19 vaccines. PRIMARY FUNDING SOURCE: Centers for Disease Control and Prevention.


Asunto(s)
COVID-19/terapia , Hospitalización/tendencias , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/uso terapéutico , Adolescente , Corticoesteroides/uso terapéutico , Adulto , Distribución por Edad , Anciano , Alanina/análogos & derivados , Alanina/uso terapéutico , Antivirales/uso terapéutico , COVID-19/etnología , COVID-19/mortalidad , Cuidados Críticos/tendencias , Estudios Transversales , Femenino , Humanos , Unidades de Cuidados Intensivos/tendencias , Tiempo de Internación/tendencias , Masculino , Persona de Mediana Edad , Pandemias , Respiración Artificial/tendencias , SARS-CoV-2 , Estados Unidos/epidemiología , Vasoconstrictores/uso terapéutico , Adulto Joven
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