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1.
PLoS One ; 19(9): e0306813, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39236015

RESUMEN

Here, we summarise the extinction risk of the sharks and rays endemic to coastal, shelf, and slope waters of the southwest Indian Ocean and adjacent waters (SWIO+, Namibia to Kenya, including SWIO islands). This region is a hotspot of endemic and evolutionarily distinct sharks and rays. Nearly one-fifth (n = 13 of 70, 18.6%) of endemic sharks and rays are threatened, of these: one is Critically Endangered, five are Endangered, and seven are Vulnerable. A further seven (10.0%) are Near Threatened, 33 (47.1%) are Least Concern, and 17 (24.3%) are Data Deficient. While the primary threat is overfishing, there are the first signs that climate change is contributing to elevated extinction risk through habitat reduction and inshore distributional shifts. By backcasting their status, few endemic species were threatened in 1980, but this changed soon after the emergence of targeted shark and ray fisheries. South Africa has the highest national conservation responsibility, followed by Mozambique and Madagascar. Yet, while fisheries management and enforcement have improved in South Africa over recent decades, substantial improvements are urgently needed elsewhere. To avoid extinction and ensure robust populations of the region's endemic sharks and rays and maintain ecosystem functionality, there is an urgent need for the strict protection of Critically Endangered and Endangered species and sustainable management of Vulnerable, Near Threatened, and Least Concern species, underpinned by species-level data collection and reduction of incidental catch.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Extinción Biológica , Tiburones , Rajidae , Animales , Tiburones/fisiología , Océano Índico , Explotaciones Pesqueras , Ecosistema
2.
J Orthop Trauma ; 38(9): 472-476, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39016440

RESUMEN

OBJECTIVES: To compare outcomes of nonoperative and percutaneous fixation of geriatric fragility lateral compression 1 (LC1) pelvic ring fractures. DESIGN: Retrospective. SETTING: Two level 1 trauma centers. PATIENT SELECTION CRITERIA: Included were patients who were 60 years or older with an isolated LC1 pelvic ring fracture managed nonoperatively or those who failed mobilization and were managed operatively with percutaneous sacral fixation. Patients with high-energy mechanisms of injury or polytrauma were excluded. OUTCOME MEASURES AND COMPARISONS: The primary outcome was pain as measured by using the visual analog scale (VAS) after treatment. Secondary outcomes included length of stay, discharge disposition, mortality, readmission rates, and complications. RESULTS: In total, 231 patients were included with a mean age of 79.5 years (range 60-100). One hundred eighty-five (80.0%) patients were female. Sixty-two (26.8%) patients received percutaneous sacral fixation after failed mobilization, and 169 (73.2%) were managed nonoperatively. In the operative group, the median time to surgery was hospital day 4. Nonoperative patients were older (81.5 ± 10.0 years vs. 74.2 ± 9.4 years, P < 0.01) and had a shorter hospital length of stay (4.8 ± 6.2 days) than the operative group (10.6 ± 9.5 days, P < 0.01). Patients in the operative group had more pain (VAS 7.9 ± 3.0) than those in the nonoperative group (VAS 6.6 ± 3.0) ( P = 0.01) on admission but had similar pain control postoperatively (VAS 4.4 ± 3.0) compared with the nonoperative group (VAS 4.5 ± 3.6) on the equivalent hospital day ( P = 0.91). Thus, patients in the operative group experienced more improvement in pain (VAS 3.3 ± 2.7) compared with the nonoperative group (VAS 1.9 ± 3.9) after treatment ( P = 0.02). Ninety-day mortality ( P = 0.21) and readmission rates ( P = 0.27) were similar for both groups. Two patients in the operative cohort sustained nerve injuries, whereas 1 patient in the nonoperative group had a nonunion and underwent surgery. CONCLUSIONS: Patients who undergo percutaneous surgical fixation for low-energy LC1 injuries have similar discharge disposition, mortality, complication rates, and readmission rates compared with patients treated nonoperatively. Percutaneous surgical fixation may provide significant pain relief for patients who failed conservative management. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.


Asunto(s)
Huesos Pélvicos , Humanos , Femenino , Masculino , Anciano , Huesos Pélvicos/lesiones , Estudios Retrospectivos , Anciano de 80 o más Años , Persona de Mediana Edad , Resultado del Tratamiento , Fijación Interna de Fracturas/métodos , Fracturas Óseas/cirugía , Fracturas Óseas/terapia , Tiempo de Internación/estadística & datos numéricos
3.
Nutrients ; 16(14)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39064683

RESUMEN

ß-glucans found in cereal grains have been previously demonstrated to improve blood glucose control; however, current understanding points to their high viscosity as the primary mechanism of action. In this work, we present a novel, highly soluble, low-viscosity ß-glucan fiber (HS-BG fiber) and a preclinical dataset that demonstrates its impact on two mechanisms related to the prevention of hyperglycemia. Our results show that HS-BG inhibits the activity of two key proteins involved in glucose metabolism, the α-glucosidase enzyme and the SGLT1 transporter, thereby having the potential to slow starch digestion and subsequent glucose uptake. Furthermore, we demonstrate in a multi-donor fecal fermentation model that HS-BG is metabolized by several different members of the gut microbiome, producing high amounts of short-chain fatty acids (SCFAs), known agonists of GPR43 receptors in the gut related to GLP-1 secretion. The production of SCFAs was verified in the translational gut model, SHIME®. Moreover, HS-BG fiber fermentation produces compounds that restored permeability in disrupted epithelial cells, decreased inflammatory chemokines (CXCL10, MCP-1, and IL-8), and increased anti-inflammatory marker (IL-10), which could improve insulin resistance. Together, these data suggest that the novel HS-BG fiber is a promising new functional ingredient that can be used to modulate postprandial glycemic responses while the high solubility and low viscosity enable easy formulation in both beverage and solid food matrices.


Asunto(s)
Glucemia , Fibras de la Dieta , Ácidos Grasos Volátiles , Microbioma Gastrointestinal , Permeabilidad , Transportador 1 de Sodio-Glucosa , beta-Glucanos , Fibras de la Dieta/farmacología , beta-Glucanos/farmacología , Glucemia/metabolismo , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Ácidos Grasos Volátiles/metabolismo , Transportador 1 de Sodio-Glucosa/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de los fármacos , Fermentación , Solubilidad , Heces/química , Heces/microbiología , Viscosidad , Inhibidores de Glicósido Hidrolasas/farmacología , Hiperglucemia/prevención & control , Funcion de la Barrera Intestinal
4.
Addict Behav ; 156: 108067, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-38823347

RESUMEN

BACKGROUND: Electronic (e-)cigarettes may help adult cigarette smokers achieve cigarette cessation, depending on patterns of e-cigarette use. Among cigarette smokers who do not use e-cigarettes, it is unclear if and how a-priori intentions for use are related to uptake patterns. Longitudinal studies have focused on established e-cigarette users or adolescent and young adult populations exclusively. METHODS: Within a nationwide randomized clinical trial (N = 638), adult cigarette smokers not currently using e-cigarettes were randomized (2:1) to receive (or not) one-month sampling of e-cigarettes. An exploratory factor analysis (EFA) was performed on an established 15-item measure assessing a-priori intentions for e-cigarette use to identify latent variables. Among those receiving e-cigarette products, regression models examined relationships between intentions and: 1) uptake (yes/no), 2) frequency (number of days per week), and 3) amount (puffing episodes per day) of e-cigarette use at one-month follow-up. RESULTS: Two factors emerged from the EFA: 1) cigarette-related intentions (e.g., cigarette cessation, no smell) and 2) novel appeal of e-cigarettes (e.g., flavors). Three items remained and were treated as separate intentions: "feels like cigarette smoking", "curiosity", and "affordability". In the final multivariable models, "feel like cigarette smoking" predicted more frequent e-cigarette use (ß = 0.187, SE = 0.086, p = 0.03); however, none of the five factors/intentions were significantly associated with uptake or amount of use. CONCLUSIONS: For adult cigarette smokers not currently using e-cigarettes, a-priori intentions for using e-cigarettes might not be predictive of if or how these products will be used in the future, suggesting that motives may not drive use behavior.


Asunto(s)
Fumar Cigarrillos , Sistemas Electrónicos de Liberación de Nicotina , Intención , Vapeo , Humanos , Masculino , Femenino , Adulto , Vapeo/psicología , Vapeo/epidemiología , Fumar Cigarrillos/psicología , Fumar Cigarrillos/epidemiología , Adulto Joven , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Adolescente , Estudios Prospectivos , Persona de Mediana Edad , Cese del Hábito de Fumar/psicología , Análisis Factorial
5.
CBE Life Sci Educ ; 23(2): ar26, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38771263

RESUMEN

Here we present the development of the Mentoring in Undergraduate Research Survey (MURS) as a measure of a range of mentoring experienced by undergraduate science researchers. We drafted items based on qualitative research and refined the items through cognitive interviews and expert sorting. We used one national dataset to evaluate the internal structure of the measure and a second national dataset to examine how responses on the MURS related to theoretically relevant constructs and student characteristics. Our factor analytic results indicate seven lower order forms of mentoring experiences: abusive supervision, accessibility, technical support, psychosocial support, interpersonal mismatch, sexual harassment, and unfair treatment. These forms of mentoring mapped onto two higher-order factors: supportive and destructive mentoring experiences. Although most undergraduates reported experiencing supportive mentoring, some reported experiencing absence of supportive as well as destructive experiences. Undergraduates who experienced less supportive and more destructive mentoring also experienced lower scientific integration and a dampening of their beliefs about the value of research. The MURS should be useful for investigating the effects of mentoring experienced by undergraduate researchers and for testing interventions aimed at fostering supportive experiences and reducing or preventing destructive experiences and their impacts.


Asunto(s)
Tutoría , Investigación , Estudiantes , Humanos , Encuestas y Cuestionarios , Femenino , Masculino , Universidades , Mentores , Investigadores
6.
Soc Sci Med ; 348: 116876, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615615

RESUMEN

Gender diverse patients (including gender diverse, transgender, and non-binary people) deserve quality health care, which has been referred to as gender affirming care. Given that practitioners' attitudes and competence can influence their provision of gender affirming care, this study used a lens of transnormativity (Bradford & Syed, 2019; Johnson, 2016) to develop a measure of practitioners' transnormative beliefs. The aim of the study was to determine if these beliefs were related to practitioners' gender affirming attitudes and perceptions of competence in gender affirming practice. Survey data were collected from Australian medical and allied health practitioners (N = 95). Exploratory factor analysis was applied to items measuring transnormative beliefs, with the results supporting three higher order factors; conditional approval, narrative, and gender role beliefs. Conditional approval reflected belief in gender diverse identity as authentic and worthy of intervention. Narrative beliefs reflected understanding of common developmental experiences among gender diverse populations, specifically experiences of victimisation and nascence. Gender role beliefs reflected belief in the existence of gender roles. In models that regressed gender affirming attitudes and self-perceived competency on all transnormative beliefs, controlling for demographics and work history, practitioners higher in conditional approval were lower in gender affirming attitudes and practitioners higher in narrative beliefs were higher in gender affirming attitudes and competency. Conditional approval was not significantly associated with competency, and gender role beliefs were not significantly associated with attitudes or competency. Results indicate that practitioners' transnormative beliefs are related to their gender affirming attitudes and suggest that targeting these beliefs through training opportunities could bridge the gap between gender diverse people's healthcare needs and the ability of healthcare practitioners to provide high quality care.


Asunto(s)
Técnicos Medios en Salud , Actitud del Personal de Salud , Personas Transgénero , Humanos , Masculino , Femenino , Australia , Adulto , Personas Transgénero/psicología , Personas Transgénero/estadística & datos numéricos , Encuestas y Cuestionarios , Persona de Mediana Edad , Técnicos Medios en Salud/psicología , Técnicos Medios en Salud/estadística & datos numéricos , Identidad de Género , Personal de Salud/psicología , Personal de Salud/estadística & datos numéricos , Atención de Afirmación de Género
7.
Science ; 383(6687): 1135-1141, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38452078

RESUMEN

The deep ocean is the last natural biodiversity refuge from the reach of human activities. Deepwater sharks and rays are among the most sensitive marine vertebrates to overexploitation. One-third of threatened deepwater sharks are targeted, and half the species targeted for the international liver-oil trade are threatened with extinction. Steep population declines cannot be easily reversed owing to long generation lengths, low recovery potentials, and the near absence of management. Depth and spatial limits to fishing activity could improve conservation when implemented alongside catch regulations, bycatch mitigation, and international trade regulation. Deepwater sharks and rays require immediate trade and fishing regulations to prevent irreversible defaunation and promote recovery of this threatened megafauna group.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Caza , Tiburones , Rajidae , Animales , Humanos , Internacionalidad , Carne , Aceites de Pescado , Biodiversidad , Océanos y Mares , Riesgo
8.
Can J Anaesth ; 71(5): 570-578, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38438681

RESUMEN

PURPOSE: To determine the 90% effective dose (ED90) of intrathecal hyperbaric bupivacaine for Cesarean delivery under combined spinal-epidural anesthesia (CSE) in parturients with super obesity (body mass index [BMI] ≥ 50 kg·m-2). METHODS: We enrolled parturients with BMI ≥ 50 kg·m-2 with term, singleton vertex pregnancies undergoing elective Cesarean delivery under CSE. An independent statistician generated the 0.75% hyperbaric bupivacaine dosing regimen in increments of 0.75 mg using a biased-coin up-down sequential allocation technique. This was combined with 15 µg fentanyl, 150 µg morphine, and normal saline to a volume of 2.05 mL. The initial and maximum doses were 9.75 mg and 12 mg, respectively. Participants, clinical team, and outcome assessors were blinded to the dose. The primary outcome was block success, defined as T6 block to pinprick within ten minutes and no intraoperative analgesic supplementation within 90 min of spinal injection. We determined the ED90 using logistic regression. RESULTS: We enrolled 45 parturients and included 42 in the analysis. All doses achieved a T6 level within ten minutes, and the primary outcome occurred in 0/1 (0%) of the 9.75-mg doses, 2/3 (67%) of the 10.5-mg doses, 21/27 (78%) of the 11.25-mg doses, and 11/11 (100%) of the 12-mg doses. The ED90 of hyperbaric bupivacaine was 11.56 mg (95% confidence interval, 11.16 to 11.99). Four parturients (9.5%) had sensory level higher than T2, but none was symptomatic or required general anesthesia. CONCLUSION: The estimated ED90 of hyperbaric bupivacaine with fentanyl and morphine in parturients with super obesity undergoing Cesarean delivery under CSE was approximately 11.5 mg. STUDY REGISTRATION: ClinicalTrials.gov (NCT03781388); first submitted 18 December 2018.


RéSUMé: OBJECTIF: Notre objectif était de déterminer la dose efficace à 90 % (DE90) de bupivacaïne hyperbare intrathécale pour l'accouchement par césarienne sous péri-rachianesthésie combinée (PRC) chez les personnes parturientes atteintes de super obésité (indice de masse corporelle [IMC] ≥ 50 kg·m−2). MéTHODE: Nous avons recruté des personnes parturientes ayant un IMC ≥ 50 kg·m−2 présentant des grossesses uniques à terme, en présentation céphalique et bénéficiant d'un accouchement par césarienne programmée sous PRC. Un·e statisticien·ne indépendant·e a généré le schéma posologique de bupivacaïne hyperbare à 0,75 % par incréments de 0,75 mg à l'aide d'une technique d'allocation séquentielle en escalier. La bupivacaïne a été combinée à 15 µg de fentanyl, 150 µg de morphine et à une solution physiologique salée jusqu'à un volume de 2,05 mL. Les doses initiale et maximale étaient respectivement de 9,75 mg et 12 mg. Les participant·es, l'équipe clinique et les personnes évaluant les résultats n'avaient pas connaissance de la dose. Le critère d'évaluation principal était la réussite du bloc, définie comme un bloc à T6 à la piqûre dans les dix minutes et aucune supplémentation analgésique peropératoire dans les 90 minutes suivant l'injection rachidienne. Nous avons déterminé la DE90 à l'aide d'une méthode de régression logistique. RéSULTATS: Nous avons recruté 45 personnes parturientes et en avons inclus 42 dans l'analyse. Toutes les doses ont atteint le niveau T6 en dix minutes, et le critère d'évaluation principal a été obtenu pour 0/1 (0 %) des doses de 9,75 mg, 2/3 (67 %) des doses de 10,5 mg, 21/27 (78 %) des doses de 11,25 mg et 11/11 (100 %) des doses de 12 mg. La DE90 de bupivacaïne hyperbare était de 11,56 mg (intervalle de confiance à 95 %, 11,16 à 11,99). Quatre personnes parturientes (9,5 %) ont affiché un niveau sensoriel supérieur à T2, mais aucune n'était symptomatique ni n'a nécessité d'anesthésie générale. CONCLUSION: La DE90 estimée de bupivacaïne hyperbare avec fentanyl et morphine chez les personnes parturientes hyperobèses bénéficiant d'une césarienne sous PRC était d'environ 11,5 mg. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT03781388); soumis pour la première fois le 18 décembre 2018.


Asunto(s)
Anestesia Epidural , Anestesia Obstétrica , Anestesia Raquidea , Femenino , Humanos , Embarazo , Anestesia Obstétrica/métodos , Anestésicos Locales , Bupivacaína , Método Doble Ciego , Fentanilo , Morfina , Obesidad
9.
Chembiochem ; 25(6): e202300773, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266114

RESUMEN

Target engagement assays typically detect and quantify the direct physical interaction of a protein of interest and its ligand through stability changes upon ligand binding. Commonly used target engagement methods detect ligand-induced stability by subjecting samples to thermal or proteolytic stress. Here we describe a new variation to these approaches called Isothermal Ligand-induced Resolubilization Assay (ILIRA), which utilizes lyotropic solubility stress to measure ligand binding through changes in target protein solubility. We identified distinct buffer systems and salt concentrations that compromised protein solubility for four diverse proteins: dihydrofolate reductase (DHFR), nucleoside diphosphate-linked moiety X motif 5 (NUDT5), poly [ADP-ribose] polymerase 1 (PARP1), and protein arginine N-methyltransferase 1 (PRMT1). Ligand-induced solubility rescue was demonstrated for these proteins, suggesting that ILIRA can be used as an additional target engagement technique. Differences in ligand-induced protein solubility were assessed by Coomassie blue staining for SDS-PAGE and dot blot, as well as by NanoOrange, Thioflavin T, and Proteostat fluorescence, thus offering flexibility for readout and assay throughput.


Asunto(s)
Unión Proteica , Ligandos , Proteolisis
10.
J Adolesc ; 96(3): 539-550, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37811912

RESUMEN

INTRODUCTION: Adolescents report using digital technologies for emotion regulation (digital ER), with the aim of feeling better (i.e., improving emotions and reducing loneliness). In this 7-day diary study, we investigated associations of digital ER, emotions, and loneliness, and tested whether prior emotional problems moderated these associations. METHOD: Participants were 312 Australian adolescents (Mage = 13.91, SD = 1.52; 44% boys). Daily surveys measured digital ER; end-of-day happiness, sadness, worry, anger, and loneliness; and peak sadness, worry, and anger. End-of day emotions were subtracted from peak emotions to calculate emotion recovery for sadness, worry, and anger. Participants were randomly selected from two symptom strata (high/low) defined by depression and social anxiety measures collected before the diary. Data were analyzed using multilevel path modeling. Cross-level interactions tested whether symptom strata moderated associations. RESULTS: Digital ER was associated with more recovery from peak to end-of-day sadness and worry, but also with increased sadness, worry, anger, and loneliness by the next end-of-day. Higher end-of-day loneliness was associated with increased next-day digital ER. Prior emotional symptoms were not a significant moderator of daily digital ER and emotion associations. CONCLUSION: Adolescents who report more digital ER in a day show more recovery from the peak of negative emotion that day, but this recovery dissipates, with digital ER also associated with increased negative emotion and loneliness by the next day for all adolescents, regardless of prior symptom status. Lonelier adolescents use more digital ER by the next day, suggesting they need support to make social connections-online or offline.


Asunto(s)
Regulación Emocional , Soledad , Masculino , Adolescente , Humanos , Femenino , Tecnología Digital , Australia , Emociones , Ira
11.
J Cardiothorac Vasc Anesth ; 38(2): 505-516, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37880038

RESUMEN

Neuraxial anesthesia (NA) has been contraindicated in patients with aortic stenosis (AS) due to concerns of sympathetic blockade and hemodynamic instability. These considerations are based on precautionary expert recommendations, supported by expected physiologic effects, but in the absence of any published scientific evidence. In light of the increasing elderly population and the prevalence of AS, this systematic review compiles available literature on NA in patients with AS to address the understanding of the anesthetic practice and safety in this population. Using a systematic approach, PubMed, Embase, and Web of Science were searched for studies of patients with AS who exclusively received NA. Primary outcomes included intraoperative and postoperative complications. Of 1,433 citations, 61 met full-text inclusion criteria, including 3,228 patients undergoing noncardiac (n = 3,146, 97.5%), obstetric (n = 69, 2.1%), and cardiac (n = 13, 0.4%) procedures. Significant data heterogeneity (local anesthetic dosing, intraoperative interventions, and measured outcomes) prevented formal metanalysis, but descriptive data are presented. Spinal block (n = 2,856, 88.5%) and epidural anesthesia (n = 397, 12.3%) were administered most frequently. Hypotension requiring vasopressors was the most common intraoperative complication-noncardiac (n = 16, 9.9%), obstetric (n = 6, 13.0%), and cardiac (n = 1, 7.7%)-with resolution in all patients and no reported intraoperative cardiovascular collapse or mortality. The relative risk of different AS severities remains unclear, and optimal medication dosing remains elusive. The authors' data suggested that NA may not be contraindicated in carefully selected patients with AS. The authors' results should inform the design of future prospective studies comparing NA and general anesthesia in patients with AS.


Asunto(s)
Anestesia Epidural , Anestesia Raquidea , Anestésicos , Estenosis de la Válvula Aórtica , Embarazo , Femenino , Humanos , Anciano , Estudios Prospectivos , Anestesia Epidural/métodos , Complicaciones Posoperatorias/prevención & control , Anestesia General , Estenosis de la Válvula Aórtica/cirugía
12.
Chem Sci ; 14(47): 13885-13892, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38075642

RESUMEN

Arynes hold immense potential as reactive intermediates in organic synthesis as they engage in a diverse range of mechanistically distinct chemical reactions. However, the poor functional group compatibility of generating arynes or their precursors has stymied their widespread use. Here, we show that generating arynes by deprotonation of an arene and elimination of an "onium" leaving group is mild, efficient and broad in scope. This is achieved by using aryl(TMP)iodonium salts (TMP = 2,4,6-trimethoxyphenyl) as the aryne precursor and potassium phosphate as the base, and a range of arynophiles are compatible. Additionally, we have performed the first quantitative analysis of functional group compatibility for several methods to generate arynes, including the method developed here and the current state of the art. Finally, we show that a range of "sensitive" functional groups such as Lewis and Brønsted acids and electrophiles are compatible under our conditions.

13.
Biomacromolecules ; 24(12): 5926-5939, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37988588

RESUMEN

Hydrogels with encapsulated cells have widespread biomedical applications, both as tissue-mimetic 3D cultures in vitro and as tissue-engineered therapies in vivo. Within these hydrogels, the presentation of cell-instructive extracellular matrix (ECM)-derived ligands and matrix stiffness are critical factors known to influence numerous cell behaviors. While individual ECM biopolymers can be blended together to alter the presentation of cell-instructive ligands, this typically results in hydrogels with a range of mechanical properties. Synthetic systems that allow for the facile incorporation and modulation of multiple ligands without modification of matrix mechanics are highly desirable. In the present work, we leverage protein engineering to design a family of xeno-free hydrogels (i.e., devoid of animal-derived components) consisting of recombinant hyaluronan and recombinant elastin-like proteins (ELPs), cross-linked together with dynamic covalent bonds. The ELP components incorporate cell-instructive peptide ligands derived from ECM proteins, including fibronectin (RGD), laminin (IKVAV and YIGSR), collagen (DGEA), and tenascin-C (PLAEIDGIELTY and VFDNFVL). By carefully designing the protein primary sequence, we form 3D hydrogels with defined and tunable concentrations of cell-instructive ligands that have similar matrix mechanics. Utilizing this system, we demonstrate that neurite outgrowth from encapsulated embryonic dorsal root ganglion (DRG) cultures is significantly modified by cell-instructive ligand content. Thus, this library of protein-engineered hydrogels is a cell-compatible system to systematically study cell responses to matrix-derived ligands.


Asunto(s)
Elastina , Péptidos , Animales , Ligandos , Péptidos/química , Elastina/química , Matriz Extracelular/química , Técnicas de Cultivo de Célula/métodos , Hidrogeles/química
14.
J Biol Chem ; 299(12): 105360, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37863263

RESUMEN

Protein arginine N-methyltransferases are a family of epigenetic enzymes responsible for monomethylation or dimethylation of arginine residues on histones. Dysregulation of protein arginine N-methyltransferase activity can lead to aberrant gene expression and cancer. Recent studies have shown that PRMT2 expression and histone H3 methylation at arginine 8 are correlated with disease severity in glioblastoma multiforme, hepatocellular carcinoma, and renal cell carcinoma. In this study, we explore a noncatalytic mechanistic role for PRMT2 in histone methylation by investigating interactions between PRMT2, histone peptides and proteins, and other PRMTs using analytical and enzymatic approaches. We quantify interactions between PRMT2, peptide ligands, and PRMT1 in a cofactor- and domain-dependent manner using differential scanning fluorimetry. We found that PRMT2 modulates the substrate specificity of PRMT1. Using calf thymus histones as substrates, we saw that a 10-fold excess of PRMT2 promotes PRMT1 methylation of both histone H4 and histone H2A. We found equimolar or a 10-fold excess of PRMT2 to PRMT1 can improve the catalytic efficiency of PRMT1 towards individual histone substrates H2A, H3, and H4. We further evaluated the effects of PRMT2 towards PRMT1 on unmodified histone octamers and mononucleosomes and found marginal PRMT1 activity improvements in histone octamers but significantly greater methylation of mononucleosomes in the presence of 10-fold excess of PRMT2. This work reveals the ability of PRMT2 to serve a noncatalytic role through its SH3 domain in driving site-specific histone methylation marks.


Asunto(s)
Histonas , Proteína-Arginina N-Metiltransferasas , Arginina/metabolismo , Histonas/metabolismo , Metilación , Proteína-Arginina N-Metiltransferasas/metabolismo , Fluorometría , Especificidad por Sustrato , Estabilidad Proteica , Unión Proteica , Dominios Proteicos , Ligandos , Humanos
15.
J Autism Dev Disord ; 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37751093

RESUMEN

INTRODUCTION: Depression impacts many individuals with autism spectrum disorder (ASD), carrying increased risk of functional impairment, hospitalization, and suicide. Prescribing medication to target depression in patients with ASD occurs despite limited available systematic data describing medication management of depression in this population. PURPOSE: The purpose of this study is to discover prescribing patterns for individuals with MDD and ASD during this time period (2004-2012) to inform current and future prescribing practices with historical data. METHOD: Drawing from a large clinical database describing the prescribing practices in patients with ASD, we identified 166 individuals with ASD (mean age 14.5 ± 8.3 years old) who received medication targeting symptoms of depression. We report prescribing rates for specific drugs, drug treatment duration, and reasons for drug discontinuation when applicable. RESULTS: Sertraline, mirtazapine, and fluoxetine were the three most commonly prescribed medications to treat comorbid depression for this patient population. Among 241 drug starts, 123 (49%) drug treatments were continued at the final reviewed follow-up visit (average treatment duration of ± 0.72 years). The most common reason for discontinuation across all medications prescribed was loss of or lack of effectiveness. CONCLUSION: This study raises concern that standard of care pharmacological treatments for depression in individuals with ASD may be less effective than in neurotypical populations. There remains a need to develop effective interventions for depression specifically tailored to the needs of individuals with ASD.

16.
J Youth Adolesc ; 52(12): 2464-2479, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37733121

RESUMEN

Adolescents face many academic pressures that require good coping skills, but coping skills can also depend on social resources, such as parental support and fewer negative interactions. The aim of this study was to determine if parental support and parental negative interactions concurrently and longitudinally relate to adolescents' ways of academic coping, above and beyond the impact of three types of academic stress, students' achievement at school (i.e., grades in school), and age. Survey data were collected from 839 Australian students in grades 5 to 10 (Mage = 12.2, SD = 1.72; 50% girls). Students completed measures of support and negative interactions with parents; academic stress from workload, external pressure (teachers/parents) to achieve, and intrapsychic pressure for high achievement; and ways of academic coping that were grouped into two positive and two negative types. Hypothesized associations were tested concurrently and from one year to the next using path modeling. Beyond the numerous significant influences of academic stress and achievement on coping, and control for age and COVID-19 timing, adolescents with more parental support reported more use of engagement coping (e.g., strategizing) and comfort-seeking, whereas those who reported more negative interactions with parents reported more use of disengagement coping (e.g., concealment) and escape. In the longitudinal model, parental support predicted an increase in engagement and comfort-seeking and a decrease in disengagement coping, whereas negative interaction with parents predicted an increase in disengagement coping. Overall, the findings support the view that coping with academic stressors will continue to depend on parent-adolescent relationships even into the teen years.


Asunto(s)
COVID-19 , Femenino , Adolescente , Humanos , Niño , Masculino , Estudios Longitudinales , Australia , Adaptación Psicológica , Padres
17.
J Craniofac Surg ; 34(7): e682-e684, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37639663

RESUMEN

Syndrome of the Trephined (SoT) is a frequently misunderstood and underdiagnosed outcome of decompressive craniectomy, especially in cases of trauma. The pressure gradient between atmospheric pressure and the sub-atmospheric intracranial pressure results in a sinking of the scalp overlying the craniectomy site. This gradually compresses the underlying brain parenchyma. This parenchymal compression can disrupt normal autoregulation and subsequent metabolism, yielding symptoms ranging from headaches, dizziness, altered behavior to changes in sensation, and difficulty with ambulation, coordination, and activities of daily living. We present a case of SoT treated with a 3D-printed custom polycarbonate external cranial orthotic that allowed us to re-establish this pressure gradient by returning the cranium to a closed system. The patient demonstrated subjective improvement in quality of life and his symptoms. This was consistent with the re-expanded brain parenchyma on CT imaging.


Asunto(s)
Craniectomía Descompresiva , Trepanación , Humanos , Actividades Cotidianas , Calidad de Vida , Cráneo/diagnóstico por imagen , Cráneo/cirugía , Impresión Tridimensional
18.
Org Lett ; 25(34): 6374-6379, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37610877

RESUMEN

Arylboron compounds are widely available and synthetically useful reagents in which the boron group is typically substituted. Herein, we show that the boron group and ortho-hydrogen atom are substituted in a formal cycloaddition reaction. This transformation is enabled by a one-pot sequence involving diaryliodonium and aryne intermediates. The scope of arylboron reagents and arynophiles is demonstrated, and the method is applied to the formal synthesis of an investigational drug candidate.

19.
Plast Reconstr Surg Glob Open ; 11(7): e5127, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37465283

RESUMEN

Regenerative peripheral nerve interface (RPNI) surgery has been demonstrated to be an effective tool as an interface for neuroprosthetics. Additionally, it has been shown to be a reproducible and reliable strategy for the active treatment and for prevention of neuromas. The purpose of this article is to provide a comprehensive review of RPNI surgery to demonstrate its simplicity and empower reconstructive surgeons to add this to their armamentarium. This article discusses the basic science of neuroma formation and prevention, as well as the theory of RPNI. An anatomic review and discussion of surgical technique for each level of amputation and considerations for other etiologies of traumatic neuromas are included. Lastly, the authors discuss the future of RPNI surgery and compare this with other active techniques for the treatment of neuromas.

20.
J Cell Sci ; 136(16)2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37505110

RESUMEN

Multiciliated cells contain hundreds of cilia whose directional movement powers the mucociliary clearance of the airways, a vital host defense mechanism. Multiciliated cell specification requires canonical Wnt signaling, which then must be turned off. Next, ciliogenesis and polarized ciliary orientation are regulated by noncanonical Wnt/planar cell polarity (Wnt/PCP) signaling. The mechanistic relationship between the Wnt pathways is unknown. We show that DKK3, a secreted canonical Wnt regulator and WNT4, a noncanonical Wnt ligand act together to facilitate a canonical to noncanonical Wnt signaling switch during multiciliated cell formation. In primary human airway epithelial cells, DKK3 and WNT4 CRISPR knockout blocks, whereas ectopic expression promotes, multiciliated cell formation by inhibiting canonical Wnt signaling. Wnt4 and Dkk3 single-knockout mice also display defective ciliated cells. DKK3 and WNT4 are co-secreted from basal stem cells and act directly on multiciliated cells via KREMEN1 and FZD6, respectively. We provide a novel mechanism that links specification to cilium biogenesis and polarization for proper multiciliated cell formation.


Asunto(s)
Células Epiteliales , Vía de Señalización Wnt , Animales , Humanos , Ratones , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Cilios/metabolismo , Células Epiteliales/metabolismo , Ratones Noqueados , Proteína Wnt4/metabolismo
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