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1.
Proc Natl Acad Sci U S A ; 121(33): e2405836121, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39116128

RESUMEN

The 2011 discovery of the first rare earth-dependent enzyme in methylotrophic Methylobacterium extorquens AM1 prompted intensive research toward understanding the unique chemistry at play in these systems. This enzyme, an alcohol dehydrogenase (ADH), features a La3+ ion closely associated with redox-active coenzyme pyrroloquinoline quinone (PQQ) and is structurally homologous to the Ca2+-dependent ADH from the same organism. AM1 also produces a periplasmic PQQ-binding protein, PqqT, which we have now structurally characterized to 1.46-Å resolution by X-ray diffraction. This crystal structure reveals a Lys residue hydrogen-bonded to PQQ at the site analogously occupied by a Lewis acidic cation in ADH. Accordingly, we prepared K142A- and K142D-PqqT variants to assess the relevance of this site toward metal binding. Isothermal titration calorimetry experiments and titrations monitored by UV-Vis absorption and emission spectroscopies support that K142D-PqqT binds tightly (Kd = 0.6 ± 0.2 µM) to La3+ in the presence of bound PQQ and produces spectral signatures consistent with those of ADH enzymes. These spectral signatures are not observed for WT- or K142A-variants or upon addition of Ca2+ to PQQ ⸦ K142D-PqqT. Addition of benzyl alcohol to La3+-bound PQQ ⸦ K142D-PqqT (but not Ca2+-bound PQQ ⸦ K142D-PqqT, or La3+-bound PQQ ⸦ WT-PqqT) produces spectroscopic changes associated with PQQ reduction, and chemical trapping experiments reveal the production of benzaldehyde, supporting ADH activity. By creating a metal binding site that mimics native ADH enzymes, we present a rare earth-dependent artificial metalloenzyme primed for future mechanistic, biocatalytic, and biosensing applications.


Asunto(s)
Methylobacterium extorquens , Methylobacterium extorquens/enzimología , Methylobacterium extorquens/metabolismo , Metaloproteínas/química , Metaloproteínas/metabolismo , Alcohol Deshidrogenasa/metabolismo , Alcohol Deshidrogenasa/química , Cristalografía por Rayos X , Cofactor PQQ/metabolismo , Cofactor PQQ/química , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Metales de Tierras Raras/química , Metales de Tierras Raras/metabolismo , Modelos Moleculares , Lantano/química , Lantano/metabolismo
2.
Circ Res ; 134(11): 1607-1635, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38781293

RESUMEN

Given advances in antiretroviral therapy, the mortality rate for HIV infection has dropped considerably over recent decades. However, people living with HIV (PLWH) experience longer life spans coupled with persistent immune activation despite viral suppression and potential toxicity from long-term antiretroviral therapy use. Consequently, PLWH face a cardiovascular disease (CVD) risk more than twice that of the general population, making it the leading cause of death among this group. Here, we briefly review the epidemiology of CVD in PLWH highlighting disparities at the intersections of sex and gender, age, race/ethnicity, and the contributions of social determinants of health and psychosocial stress to increased CVD risk among individuals with marginalized identities. We then overview the pathophysiology of HIV and discuss the primary factors implicated as contributors to CVD risk among PLWH on antiretroviral therapy. Subsequently, we highlight the functional evidence of premature vascular dysfunction as an early pathophysiological determinant of CVD risk among PLWH, discuss several mechanisms underlying premature vascular dysfunction in PLWH, and synthesize current research on the pathophysiological mechanisms underlying accelerated vascular aging in PLWH, focusing on immune activation, chronic inflammation, and oxidative stress. We consider understudied aspects such as HIV-related changes to the gut microbiome and psychosocial stress, which may serve as mechanisms through which exercise can abrogate accelerated vascular aging. Emphasizing the significance of exercise, we review various modalities and their impacts on vascular health, proposing a holistic approach to managing CVD risks in PLWH. The discussion extends to critical future study areas related to vascular aging, CVD, and the efficacy of exercise interventions, with a call for more inclusive research that considers the diversity of the PLWH population.


Asunto(s)
Enfermedades Cardiovasculares , Infecciones por VIH , Humanos , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones , Enfermedades Cardiovasculares/epidemiología , Envejecimiento , Ejercicio Físico , Terapia por Ejercicio , Factores de Riesgo
3.
Am J Hum Genet ; 109(8): 1366-1387, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35931049

RESUMEN

A major challenge of genome-wide association studies (GWASs) is to translate phenotypic associations into biological insights. Here, we integrate a large GWAS on blood lipids involving 1.6 million individuals from five ancestries with a wide array of functional genomic datasets to discover regulatory mechanisms underlying lipid associations. We first prioritize lipid-associated genes with expression quantitative trait locus (eQTL) colocalizations and then add chromatin interaction data to narrow the search for functional genes. Polygenic enrichment analysis across 697 annotations from a host of tissues and cell types confirms the central role of the liver in lipid levels and highlights the selective enrichment of adipose-specific chromatin marks in high-density lipoprotein cholesterol and triglycerides. Overlapping transcription factor (TF) binding sites with lipid-associated loci identifies TFs relevant in lipid biology. In addition, we present an integrative framework to prioritize causal variants at GWAS loci, producing a comprehensive list of candidate causal genes and variants with multiple layers of functional evidence. We highlight two of the prioritized genes, CREBRF and RRBP1, which show convergent evidence across functional datasets supporting their roles in lipid biology.


Asunto(s)
Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Cromatina/genética , Genómica , Humanos , Lípidos/genética , Polimorfismo de Nucleótido Simple/genética
4.
FASEB J ; 38(8): e23621, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38651653

RESUMEN

Denervated myofibers and senescent cells are hallmarks of skeletal muscle aging. However, sparse research has examined how resistance training affects these outcomes. We investigated the effects of unilateral leg extensor resistance training (2 days/week for 8 weeks) on denervated myofibers, senescent cells, and associated protein markers in apparently healthy middle-aged participants (MA, 55 ± 8 years old, 17 females, 9 males). We obtained dual-leg vastus lateralis (VL) muscle cross-sectional area (mCSA), VL biopsies, and strength assessments before and after training. Fiber cross-sectional area (fCSA), satellite cells (Pax7+), denervated myofibers (NCAM+), senescent cells (p16+ or p21+), proteins associated with denervation and senescence, and senescence-associated secretory phenotype (SASP) proteins were analyzed from biopsy specimens. Leg extensor peak torque increased after training (p < .001), while VL mCSA trended upward (interaction p = .082). No significant changes were observed for Type I/II fCSAs, NCAM+ myofibers, or senescent (p16+ or p21+) cells, albeit satellite cells increased after training (p = .037). While >90% satellite cells were not p16+ or p21+, most p16+ and p21+ cells were Pax7+ (>90% on average). Training altered 13 out of 46 proteins related to muscle-nerve communication (all upregulated, p < .05) and 10 out of 19 proteins related to cellular senescence (9 upregulated, p < .05). Only 1 out of 17 SASP protein increased with training (IGFBP-3, p = .031). In conclusion, resistance training upregulates proteins associated with muscle-nerve communication in MA participants but does not alter NCAM+ myofibers. Moreover, while training increased senescence-related proteins, this coincided with an increase in satellite cells but not alterations in senescent cell content or SASP proteins. These latter findings suggest shorter term resistance training is an unlikely inducer of cellular senescence in apparently healthy middle-aged participants. However, similar study designs are needed in older and diseased populations before definitive conclusions can be drawn.


Asunto(s)
Senescencia Celular , Entrenamiento de Fuerza , Humanos , Entrenamiento de Fuerza/métodos , Masculino , Femenino , Persona de Mediana Edad , Senescencia Celular/fisiología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiología , Biomarcadores/metabolismo , Células Satélite del Músculo Esquelético/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Factor de Transcripción PAX7/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Adulto , Músculo Cuádriceps/metabolismo , Músculo Cuádriceps/inervación
5.
Proc Natl Acad Sci U S A ; 119(48): e2212736119, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36409914

RESUMEN

The parathyroid hormone type 1 receptor (PTHR1), a Class B GPCR, is activated by long polypeptides, including drugs for osteoporosis and hypoparathyroidism. The PTHR1 engages peptide agonists via a two-step mechanism. Initial contact involves the extracellular domain (ECD), which has been thought to contribute primarily to receptor-peptide binding, and then the N terminus of the peptide engages the receptor transmembrane domain (TMD), which is thought to control the message conveyed to intracellular partners. This mechanism has been suggested to apply to other Class B GPCRs as well. Here, we show that modification of a PTHR1 agonist at ECD-contact sites can alter the signaling profile, an outcome that is not accommodated by the current two-step binding model. Our data support a modified two-step binding model in which agonist orientation on the ECD surface can influence the geometry of agonist-TMD engagement. This expanded binding model offers a mechanism by which altering ECD-contact residues can affect signaling profile. Our discoveries provide a rationale for exploring agonist modifications distal from the TMD-contact region in future efforts to optimize therapeutic performance of peptide hormone analogs.


Asunto(s)
Receptor de Hormona Paratiroídea Tipo 1 , Transducción de Señal , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Unión Proteica , Dominios Proteicos , Péptidos/metabolismo
6.
Am J Physiol Cell Physiol ; 327(2): C446-C461, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38912731

RESUMEN

Adults with type 1 diabetes (T1D) have an elevated risk for cardiovascular disease (CVD) compared with the general population. HbA1c is the primary modifiable risk factor for CVD in T1D. Fewer than 1% of patients achieve euglycemia (<5.7% HbA1c). Ketogenic diets (KD; ≤50 g carbohydrate/day) may improve glycemia and downstream vascular dysfunction in T1D by reducing HbA1c and insulin load. However, there are concerns regarding the long-term CVD risk from a KD. Therefore, we compared data collected in a 60-day window in an adult with T1D on exogenous insulin who consumed a KD for 10 years versus normative values in those with T1D (T1D norms). The participant achieved euglycemia with an HbA1c of 5.5%, mean glucose of 98 [5] mg/dL (median [interquartile range]), 90 [11]% time-in-range 70-180 mg/dL (T1D norms: 1st percentile for all), and low insulin requirements of 0.38 ± 0.03 IU/kg/day (T1D norms: 8th percentile). Seated systolic blood pressure (SBP) was 113 mmHg (T1D norms: 18th percentile), while ambulatory awake SBP was 132 ± 15 mmHg (T1D target: <130 mmHg), blood triglycerides were 69 mg/dL (T1D norms: 34th percentile), low-density lipoprotein was 129 mg/dL (T1D norms: 60th percentile), heart rate was 56 beats/min (T1D norms: >1SD below the mean), carotid-femoral pulse wave velocity was 7.17 m/s (T1D norms: lowest quartile of risk), flow-mediated dilation was 12.8% (T1D norms: >1SD above mean), and cardiac vagal baroreflex gain was 23.5 ms/mmHg (T1D norms: >1SD above mean). Finally, there was no indication of left ventricular diastolic dysfunction from echocardiography. Overall, these data demonstrate below-average CVD risk relative to T1D norms despite concerns regarding the long-term impact of a KD on CVD risk.NEW & NOTEWORTHY Adults with type 1 diabetes (T1D) have a 10-fold higher risk for cardiovascular disease (CVD) compared with the general population. We assessed cardiovascular health metrics in an adult with T1D who presented with a euglycemic HbA1c after following a ketogenic diet for the past 10 years. Despite concerns about the ketogenic diet increasing CVD risk, the participant exhibited below-average CVD risk relative to others with T1D when considering all outcomes together.


Asunto(s)
Glucemia , Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 1 , Dieta Cetogénica , Humanos , Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 1/sangre , Adulto , Glucemia/metabolismo , Masculino , Enfermedades Cardiovasculares/dietoterapia , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/fisiopatología , Femenino , Hemoglobina Glucada/metabolismo , Presión Sanguínea/fisiología , Insulina/sangre , Factores de Riesgo , Frecuencia Cardíaca/fisiología
7.
Am J Physiol Renal Physiol ; 326(1): F135-F142, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37942539

RESUMEN

Several human studies have used the mitochondrial antioxidant MitoQ. Recent in vitro data indicating that MitoQ may induce nephrotoxicity caused concern regarding the safety of MitoQ on the kidneys, but the doses were supraphysiological. Therefore, we sought to determine whether acute MitoQ elicits changes in urinary biomarkers associated with tubular injury in healthy adults with our hypothesis being there would be no changes. Using a randomized crossover design, 32 healthy adults (16 females and 16 males, 29 ± 11 yr old) consumed MitoQ (100-160 mg based on body mass) or placebo capsules. We obtained serum samples and a 4- to 6-h postcapsule consumption urine sample. We assessed creatinine clearance and urine kidney injury biomarkers including the chitinase 3-like-1 gene product YKL-40, kidney-injury marker-1, monocyte chemoattractant protein-1, epidermal growth factor, neutrophil gelatinase-associated lipocalin, interleukin-18, and uromodulin using multiplex assays. We used t tests, Wilcoxon tests, and Hotelling's T2 to assess global differences in urinary kidney injury markers between conditions. Acute MitoQ supplementation did not influence urine flow rate (P = 0.086, rrb = 0.39), creatinine clearance (P = 0.085, rrb = 0.42), or urinary kidney injury markers (T22,8 = 30.6, P = 0.121, univariate ps > 0.064). Using exploratory univariate analysis, MitoQ did not alter individual injury markers compared with placebo (e.g., placebo vs. MitoQ: YKL-40, 507 ± 241 vs. 442 ± 236 pg/min, P = 0.241; kidney injury molecule-1, 84.1 ± 43.2 vs. 76.2 ± 51.2 pg/min, P = 0.890; and neutrophil gelatinase-associated lipocalin, 10.8 ± 10.1 vs. 9.83 ± 8.06 ng/min, P = 0.609). In conclusion, although longer-term surveillance and data are needed in clinical populations, our findings suggest that acute high-dose MitoQ had no effect on urinary kidney injury markers in healthy adults.NEW & NOTEWORTHY We found acute high-dose mitochondria-targeted antioxidant (MitoQ) supplementation was not nephrotoxic and had no effect on markers of acute kidney injury in healthy adults. These findings can help bolster further confidence in the safety of MitoQ, particularly for future investigations seeking to examine the role of mitochondrial oxidative stress, via acute MitoQ supplementation, on various physiological outcomes.


Asunto(s)
Lesión Renal Aguda , Antioxidantes , Masculino , Adulto , Femenino , Humanos , Lipocalina 2/metabolismo , Estudios Cruzados , Proteína 1 Similar a Quitinasa-3/metabolismo , Antioxidantes/metabolismo , Creatinina/metabolismo , Riñón/metabolismo , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/diagnóstico , Biomarcadores/orina
8.
Angiogenesis ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38922557

RESUMEN

BACKGROUND: Pathological angiogenesis causes significant vision loss in neovascular age-related macular degeneration and other retinopathies with neovascularization (NV). Neuronal/glial-vascular interactions influence the release of angiogenic and neurotrophic factors. We hypothesized that botulinum neurotoxin serotype A (BoNT/A) modulates pathological endothelial cell proliferation through glial cell activation and growth factor release. METHODS: A laser-induced choroidal NV (CNV) was employed to investigate the anti-angiogenic effects of BoNT/A. Fundus fluorescence angiography, immunohistochemistry, and real-time PCR were used to assess BoNT/A efficacy in inhibiting CNV and the molecular mechanisms underlying this inhibition. Neuronal and glial suppressor of cytokine signaling 3 (SOCS3) deficient mice were used to investigate the molecular mechanisms of BoNT/A in inhibiting CNV via SOCS3. FINDINGS: In laser-induced CNV mice with intravitreal BoNT/A treatment, CNV lesions decreased > 30%; vascular leakage and retinal glial activation were suppressed; and Socs3 mRNA expression was induced while vascular endothelial growth factor A (Vegfa) mRNA expression was suppressed. The protective effects of BoNT/A on CNV development were diminished in mice lacking neuronal/glial SOCS3. CONCLUSION: BoNT/A suppressed laser-induced CNV and glial cell activation, in part through SOCS3 induction in neuronal/glial cells. BoNT/A treatment led to a decrease of pro-angiogenic factors, including VEGFA, highlighting the potential of BoNT/A as a therapeutic intervention for pathological angiogenesis in retinopathies.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38995211

RESUMEN

BACKGROUND: Nighttime BP and BP dipping (daytime-nighttime BP) are prognostic for cardiovascular disease. Compared with other racial/ethnic groups, Black Americans exhibit elevated nighttime BP and attenuated BP dipping. Neighborhood deprivation may contribute to disparities in cardiovascular health, but its effects on resting and ambulatory BP patterns in young adults is unclear. Therefore, we examined associations between neighborhood deprivation with resting and nighttime BP and BP dipping in young Black and White adults. METHODS: We recruited 19 Black and 28 White participants (23 M/24 F, 21±1 years, body mass index: 26±4 kg/m2) for 24-hour ambulatory BP monitoring. We assessed resting BP, nighttime BP, and BP dipping (absolute dip and nighttime:daytime BP ratio). We used the area deprivation index (ADI) to assess average neighborhood deprivation during early- and mid-childhood, and adolescence. RESULTS: Compared with White participants, Black participants exhibited higher resting systolic and diastolic BP (ps≤0.029), nighttime systolic BP (114±9 vs. 108±9 mmHg, p=0.049), diastolic BP (63±8 vs. 57±7 mmHg, p=0.010), and attenuated absolute systolic BP dipping (12±5 vs. 9±7 mmHg, p=0.050). Black participants experienced greater average ADI scores compared with White participants (110(10) vs. 97(22), p=0.002), and select ADI scores correlated with resting BP and some ambulatory BP measures. Within each race, select ADI scores correlated with some BP measures for Black participants, but there were no ADI and BP correlations for White participants. CONCLUSIONS: Our findings suggest neighborhood deprivation may contribute to higher resting BP and impaired ambulatory BP patterns in young adults warranting further investigation in larger cohorts.

10.
Am J Physiol Heart Circ Physiol ; 326(1): H238-H255, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37999647

RESUMEN

In cardiovascular research, sex and gender have not typically been considered in research design and reporting until recently. This has resulted in clinical research findings from which not only all women, but also gender-diverse individuals have been excluded. The resulting dearth of data has led to a lack of sex- and gender-specific clinical guidelines and raises serious questions about evidence-based care. Basic research has also excluded considerations of sex. Including sex and/or gender as research variables not only has the potential to improve the health of society overall now, but it also provides a foundation of knowledge on which to build future advances. The goal of this guidelines article is to provide advice on best practices to include sex and gender considerations in study design, as well as data collection, analysis, and interpretation to optimally establish rigor and reproducibility needed to inform clinical decision-making and improve outcomes. In cardiovascular physiology, incorporating sex and gender is a necessary component when optimally designing and executing research plans. The guidelines serve as the first guidance on how to include sex and gender in cardiovascular research. We provide here a beginning path toward achieving this goal and improve the ability of the research community to interpret results through a sex and gender lens to enable comparison across studies and laboratories, resulting in better health for all.


Asunto(s)
Investigación Biomédica , Cardiología , Caracteres Sexuales , Femenino , Humanos , Masculino , Sistema Cardiovascular
11.
Am J Physiol Regul Integr Comp Physiol ; 327(2): R195-R207, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38842515

RESUMEN

We sought to determine the effects of acute simulated altitude on the maximal lactate steady state (MLSS) and physiological responses to cycling at and 10 W above the MLSS-associated power output (PO) (MLSSp and MLSSp+10, respectively). Eleven (4 females) participants (means [SD]; 28 [4] yr; V̇o2max: 54.3 [6.9] mL·kg-1·min-1) acclimatized to ∼1,100 m performed 30-min constant PO trials in simulated altitudes of 0 m sea level (SL), 1,111 m mild altitude (MILD), and 2,222 m moderate altitude (MOD). MLSSp, defined as the highest PO with stable (<1 mM change) blood lactate concentration ([BLa]) between 10 and 30 min, was significantly lower in MOD (209 [54] W) compared with SL (230 [56] W; P < 0.001) and MILD (225 [58] W; P = 0.001), but MILD and SL were not different (P = 0.12). V̇o2 and V̇co2 decreased at higher simulated altitudes due to lower POs (P < 0.05), but other end-exercise physiological responses (e.g., [BLa], ventilation [V̇e], heart rate [HR]) were not different between conditions at MLSSp or MLSSp + 10 (P > 0.05). At the same absolute intensity (MLSSp for MILD), [BLa], HR, and V̇E and all perceptual variables were exacerbated in MOD compared with SL and MILD (P < 0.05). Maximum voluntary contraction, voluntary activation, and potentiated twitch forces were exacerbated at MLSSp + 10 relative to MLSSp within conditions (P < 0.05); however, condition did not affect performance fatiguability at the same relative or absolute intensity (P > 0.05). As MLSSp decreased in hypoxia, adjustments in PO are needed to ensure the same relative intensity across altitudes, but common indices of exercise intensity may facilitate exercise prescription and monitoring in hypoxia.NEW & NOTEWORTHY This study demonstrates the power output and metabolic rate associated with the maximal lactate steady-state (MLSS) decline in response to simulated altitude; however, common indices of exercise intensity remained unchanged when cycling was performed at the work rate associated with MLSS at each simulated altitude. These results support previous studies that investigated the effects of hypoxia on alternative measures of the critical intensity of exercise and will inform exercise prescription/monitoring across altitudes.


Asunto(s)
Altitud , Ácido Láctico , Consumo de Oxígeno , Humanos , Ácido Láctico/sangre , Femenino , Adulto , Masculino , Consumo de Oxígeno/fisiología , Aclimatación/fisiología , Ciclismo , Hipoxia/fisiopatología , Hipoxia/sangre , Adulto Joven , Músculo Esquelético/metabolismo , Biomarcadores/sangre
12.
Chemistry ; : e202304292, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009481

RESUMEN

To evaluate bifunctional ligand reactivity involving NH acidic sites in the secondary coordination sphere of metal complexes, complexes where the proton has been substituted with a methyl group (NMe) are often investigated. An alternative strategy would involve substitution of the NH group for an O. This contribution considers and compares the merits of these approaches; the synthesis and characterization of cationic square planar Rh carbonyl complexes bearing diprotic bispyrazole pyridine ligand L1, and the bis-methylated pyrazole pyridine ligand L1Me are described. The syntheses and characterization of the novel monoprotic pyrazole isoxazole pyridine ligand L2 and aprotic bisisoxazole pyridine ligand L3, and their corresponding Rh carbonyl complexes are also described. The different CO stretching frequencies of all four Rh-complexes suggest that substitutions of NH with NMe, as well as O, lead to significant electronic differences, and these differences are further demonstrated to lead to different ligand addition/substitution reactivities of the four isoelectronic Rh-complexes. Overall, the results suggest that the electronic differences arising due to NH substitutions can be significant and must be accounted for prior to invoking the participation of the proton.

13.
Am J Bot ; 111(7): e16372, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39010697

RESUMEN

PREMISE: Characterization and phylogenetic integration of fossil angiosperms with uncertain affinities is relatively limited, which may obscure the diversity of extinct higher taxa in the flowering plant tree of life. The order Cornales contains a diversity of extinct taxa with uncertain familial affinities that make it an ideal group for studying turnover in angiosperms. Here, we describe a new extinct genus of Cornales unassignable to an extant family and conduct a series of phylogenetic analyses to reconstruct relationships of fossils across the order. METHODS: Two permineralized endocarps were collected from the Cedar District Formation (Campanian, 82-80 Ma) of Sucia Island, State of Washington, United States. Fossils were sectioned with the cellulose acetate peel technique and incorporated into a morphological dataset. To assess the utility of this dataset to accurately place taxa in their respective clades, we used a series of phylogenetic pseudofossilization analyses. We then conducted a total-evidence analysis and a scaffold-based approach to determine relationships of fossils. RESULTS: Based on their unique combination of characters, the fossils represent a new genus, Fenestracarpa washingtonensis gen. nov. et sp. nov. Pseudofossilization analyses indicate that our morphological dataset can be used to accurately recover taxa at the major clade to family level, generally with moderate to high support. The total-evidence and scaffold-based analyses recovered Fenestracarpa and other fossil genera in an entirely extinct clade within Cornales. CONCLUSIONS: Our findings increase the reported diversity of extinct Cornales and indicate that the order's initial radiation likely included the divergence of an extinct higher clade that endured the end-Cretaceous Mass extinction but perished during the Cenozoic.


Asunto(s)
Extinción Biológica , Fósiles , Filogenia , Fósiles/anatomía & histología , Magnoliopsida/anatomía & histología , Magnoliopsida/genética , Magnoliopsida/clasificación , Washingtón
14.
Curr Hypertens Rep ; 26(1): 43-58, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37878224

RESUMEN

PURPOSE OF REVIEW: To review underlying mechanisms and environmental factors that may influence racial disparities in the development of salt-sensitive blood pressure. RECENT FINDINGS: Our group and others have observed racial differences in diet and hydration, which may influence salt sensitivity. Dietary salt elicits negative alterations to the gut microbiota and immune system, which may increase hypertension risk, but little is known regarding potential racial differences in these physiological responses. Antioxidant supplementation and exercise offset vascular dysfunction following dietary salt, including in Black adults. Furthermore, recent work proposes the role of racial differences in exposure to social determinants of health, and differences in health behaviors that may influence risk of salt sensitivity. Physiological and environmental factors contribute to the mechanisms that manifest in racial differences in salt-sensitive blood pressure. Using this information, additional work is needed to develop strategies that can attenuate racial disparities in salt-sensitive blood pressure.


Asunto(s)
Hipertensión , Adulto , Humanos , Hipertensión/etiología , Cloruro de Sodio Dietético/efectos adversos , Factores Raciales , Presión Sanguínea , Cloruro de Sodio
15.
J Phycol ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38817114

RESUMEN

Biogeographic structure in marine protist communities is shaped by a combination of dispersal potential and environmental selection. High-throughput sequencing and global sampling efforts have helped better resolve the composition and functions of these communities in the world's oceans using both molecular and visual methods. However, molecular barcoding data are critically lacking across the Indo-Pacific, a region widely considered the epicenter of marine biodiversity. To fill this gap, we characterized protist communities in four sampling regions across Indonesia that represent the latitudinal, longitudinal, and human population gradients of the region: Lombok, Wakatobi, Misool, and Waigeo. We show high spatial structuring in marine protist communities across Indonesia, and biotic factors appear to play little role in driving this observed structure. Our results appear to be driven by abiotic factors linked to surface current patterns across the Indo-Pacific as a result of: (1) a choke point in circulation at the Indonesian Throughflow leading to low diatom diversity in Lombok, Wakatobi, and Misool; (2) an increase in nutrient availability at the edge of the Halmahera Eddy in Waigeo, leading to an increase in diatom diversity; and/or (3) seasonal variations in protist communities in line with shifts in velocity of the Indonesian Throughflow. Overall, our results highlight the importance of abiotic factors in shaping protist communities on broad geographic scales over biotic, top-down pressures, such as grazing from higher trophic levels.

16.
J Oral Maxillofac Surg ; 82(7): 852-861, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38621664

RESUMEN

BACKGROUND: Quick Sequential Organ Failure Assessment (qSOFA) is recommended to identify sepsis. Odontogenic infection (OI) can progress to sepsis, causing systematic inflammatory complications or organ failure. PURPOSE: The purpose of the study was to measure the association between OI location and risk for sepsis at admission. STUDY DESIGN, SETTING, AND SAMPLE: This retrospective cohort study included subjects treated for OI at Baylor University Medical Center in Dallas, TX, from January 9, 2019 to July 30, 2022. Subjects > 18 years old who were treated under general anesthesia were included. OI limited to periapical, vestibular, buccal, and/or canine spaces were excluded from the sample. PREDICTOR VARIABLE: The primary predictor variable was OI anatomic location (superficial or deep). Superficial OI infection includes submental, submandibular, sublingual, submasseteric, and/or superficial temporal spaces. Deep OI includes pterygomandibular, deep temporal, lateral pharyngeal, retropharyngeal, pretracheal, and/or prevertebral. MAIN OUTCOME VARIABLES: The primary outcome variable was risk for sepsis measured using a qSOFA score (0 to 3). A higher score (>0) indicates the patient has a high risk for sepsis. COVARIATES: Covariates were demographics, clinical, laboratory, and radiological findings, antibiotic route, postoperative endotracheal intubation, tracheostomy, intensive care unit, admission, and length of stay. ANALYSES: Descriptive and bivariate analyses were performed. A χ2 test was used for categorical variables. The Mann-Whitney U test was used for continuous variables. Statistical significance was P < .05. RESULTS: The sample was composed of 168 subjects with a mean age of 42.8 ± 21.5 and 69 (48.6%) subjects were male. There were 11 (6.5%) subjects with a qSOFA score > 0. The relative risk of a qSOFA > 0 for a deep OI is 5.4 times greater than for a superficial OI (136 (95.8) versus 21 (80.8%): RR (95% confidence interval): 5.4 (1.51 to 19.27), P = .004). After adjusting for age, sex, American Society of Anesthesiologists score, and involved anatomical spaces, there was a significant correlation between laterality and the number of involved anatomical spaces and qSOFA score (odd ratio = 9.13, 95% confidence interval: 2.48 to 33.55, adjusted P = <.001). CONCLUSION AND RELEVANCE: The study findings suggest that the OI location is associated with the qSOFA score >0.


Asunto(s)
Infección Focal Dental , Sepsis , Humanos , Sepsis/etiología , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Infección Focal Dental/complicaciones , Factores de Riesgo , Puntuaciones en la Disfunción de Órganos , Adulto , Anciano
17.
Eur J Orthop Surg Traumatol ; 34(4): 1877-1882, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38441634

RESUMEN

PURPOSE: With advances in orthopedic implants, the use of intramedullary lengthening devices has gained increasing popularity as an alternative technique compared to lengthening with external fixators, with alleged comparable or better outcomes. The aim of this study is to report our single-center technique and outcomes of combined ankle arthrodesis and proximal tibial lengthening using external fixator with a motorized intramedullary nail, respectively. METHOD: Fourteen patients with post-traumatic advanced ankle arthritis underwent staged ankle arthrodesis with external fixator and proximal tibial lengthening using the PRECICE® ILN. Amount of shortening, length achieved, bone healing index, infection rate, ankle fusion rate, and ASAMI score were evaluated. RESULTS: The average age was 44 years old (range, 30-62). The mean follow up is 70 months (range, 43-121.4). The average amount of limb shortening for patients after ankle fusion was 36.7 mm (18-50) while lengthening was 35.9 mm (range, 18-50). Patients had the nail implanted for an average of 479 days (range, 248-730). Ankle fusions were healed in an average of 178.3 days. There were no surgical infections. All osteotomy-lengthening sites healed after an average 202 days (106-365). The mean bone healing index (BHI) was 56.0 days/cm (21.2-123.6) among the whole cohort. There were no cases of nonunion. ASAMI bone scores were excellent or good among all patients. CONCLUSION: Ankle arthrodesis with external fixation along with proximal tibial lengthening using motorized IMN yielded high rates of fusion and successful lengthening. This technique could be offered as a reasonable alternative to using external fixation for both purposes. LEVEL OF EVIDENCE: Level IV, Retrospective cohort study.


Asunto(s)
Articulación del Tobillo , Artrodesis , Clavos Ortopédicos , Fijadores Externos , Recuperación del Miembro , Humanos , Artrodesis/métodos , Artrodesis/instrumentación , Adulto , Persona de Mediana Edad , Masculino , Articulación del Tobillo/cirugía , Articulación del Tobillo/fisiopatología , Femenino , Recuperación del Miembro/métodos , Alargamiento Óseo/métodos , Alargamiento Óseo/instrumentación , Tibia/cirugía , Artritis/cirugía , Estudios Retrospectivos , Diferencia de Longitud de las Piernas/cirugía , Diferencia de Longitud de las Piernas/etiología , Resultado del Tratamiento , Traumatismos del Tobillo/cirugía
18.
Artículo en Inglés | MEDLINE | ID: mdl-38981919

RESUMEN

OBJECTIVES: To analyze our patient's complication profile and rate after removal of hardware (ROH) surgery, and survey our patients to ask their overall status and improvement in symptomatology post-operatively. DESIGN: Retrospective chart review and survey. SETTING: Academic, tertiary referral center. PATIENTS/PARTICIPANTS: 173 patients with 314 pieces of hardware. Seventy-six patients (43.9%) responded to our survey. INTERVENTION: ROH surgery. MAIN OUTCOME MEASUREMENTS: Patient demographics and complications were recorded. All patients were sent a brief 3-question survey which asked: (1) Why did you get your hardware removed? (2) How did your overall status change after ROH? (3) How did the ROH affect your stiffness, pain, swelling, and mobility? RESULTS: There were 10 complications (5.5%): 5 infections, 2 with unresolved pain, 1 hematoma, 1 chronic regional pain syndrome exacerbation, and 1 recurrent deformity. All infections were treated with oral antibiotics and improved. All other complications resolved with treatment except for the patient who developed recurrent deformity. Patients underwent ROH surgery because their doctor suggested it (76.3%) and to improve mobility (39.5%). 86.9% reported their overall status improved after ROH. They improved regarding stiffness (73.7%), pain (73.6%), swelling (61.8%), and mobility (76.3%). Similar results were seen among different implants removed. CONCLUSIONS: The majority of patients who underwent percutaneous ROH were satisfied. They reported improvement in stiffness, pain, swelling and mobility (greatest improvement). The complication rate was low (5.5%). ROH can be a meaningful operation to patients allowing them to improve their quality of life with a low complication rate. LEVEL OF EVIDENCE: Level IV.

19.
Dev Biol ; 491: 105-112, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36113571

RESUMEN

During neural tube closure, neural ectoderm cells constrict their apical surfaces to bend and fold the tissue into a tube that will become the central nervous system. Recent data from mice and humans with neural tube defects suggest that key genes required for neural tube closure can exert non-cell autonomous effects on cell behavior, but the nature of these effects remains obscure. Here, we coupled tissue-scale, high-resolution time-lapse imaging of the closing neural tube of Xenopus to multivariate regression modeling, and we show that medial actin accumulation drives apical constriction non-autonomously in neighborhoods of cells, rather than solely in individual cells. To further explore this effect, we examined mosaic crispant embryos and identified both autonomous and non-autonomous effects of the apical constriction protein Shroom3.


Asunto(s)
Actinas , Tubo Neural , Actinas/metabolismo , Animales , Humanos , Ratones , Proteínas de Microfilamentos/metabolismo , Morfogénesis , Tubo Neural/metabolismo , Neurulación/fisiología , Análisis de Regresión
20.
Plant J ; 111(5): 1453-1468, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35816116

RESUMEN

Large enzyme families catalyze metabolic diversification by virtue of their ability to use diverse chemical scaffolds. How enzyme families attain such functional diversity is not clear. Furthermore, duplication and promiscuity in such enzyme families limits their functional prediction, which has produced a burgeoning set of incompletely annotated genes in plant genomes. Here, we address these challenges using BAHD acyltransferases as a model. This fast-evolving family expanded drastically in land plants, increasing from one to five copies in algae to approximately 100 copies in diploid angiosperm genomes. Compilation of >160 published activities helped visualize the chemical space occupied by this family and define eight different classes based on structural similarities between acceptor substrates. Using orthologous groups (OGs) across 52 sequenced plant genomes, we developed a method to predict BAHD acceptor substrate class utilization as well as origins of individual BAHD OGs in plant evolution. This method was validated using six novel and 28 previously characterized enzymes and helped improve putative substrate class predictions for BAHDs in the tomato genome. Our results also revealed that while cuticular wax and lignin biosynthetic activities were more ancient, anthocyanin acylation activity was fixed in BAHDs later near the origin of angiosperms. The OG-based analysis enabled identification of signature motifs in anthocyanin-acylating BAHDs, whose importance was validated via molecular dynamic simulations, site-directed mutagenesis and kinetic assays. Our results not only describe how BAHDs contributed to evolution of multiple chemical phenotypes in the plant world but also propose a biocuration-enabled approach for improved functional annotation of plant enzyme families.


Asunto(s)
Aciltransferasas , Solanum lycopersicum , Aciltransferasas/metabolismo , Antocianinas/metabolismo , Genoma de Planta/genética , Solanum lycopersicum/genética , Filogenia , Plantas/metabolismo
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