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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38839074

RESUMEN

Skin sympathetic nerve activity (SSNA) is primarily involved in thermoregulation and emotional expression; however, the brain regions involved in the generation of SSNA are not completely understood. In recent years, our laboratory has shown that blood-oxygen-level-dependent signal intensity in the ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) are positively correlated with bursts of SSNA during emotional arousal and increases in signal intensity in the vmPFC occurring with increases in spontaneous bursts of SSNA even in the resting state. We have recently shown that unilateral transcranial alternating current stimulation (tACS) of the dlPFC causes modulation of SSNA but given that the current was delivered between electrodes over the dlPFC and the nasion, it is possible that the effects were due to current acting on the vmPFC. To test this, we delivered tACS to target the right vmPFC or dlPFC and nasion and recorded SSNA in 11 healthy participants by inserting a tungsten microelectrode into the right common peroneal nerve. The similarity in SSNA modulation between ipsilateral vmPFC and dlPFC suggests that the ipsilateral vmPFC, rather than the dlPFC, may be causing the modulation of SSNA during ipsilateral dlPFC stimulation.


Asunto(s)
Corteza Prefrontal , Piel , Sistema Nervioso Simpático , Estimulación Transcraneal de Corriente Directa , Humanos , Corteza Prefrontal/fisiología , Masculino , Femenino , Adulto , Sistema Nervioso Simpático/fisiología , Adulto Joven , Piel/inervación , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Eléctrica/métodos , Nervio Peroneo/fisiología , Lateralidad Funcional/fisiología
2.
Nat Commun ; 15(1): 4696, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824133

RESUMEN

Age-related microangiopathy, also known as small vessel disease (SVD), causes damage to the brain, retina, liver, and kidney. Based on the DNA damage theory of aging, we reasoned that genomic instability may underlie an SVD caused by dominant C-terminal variants in TREX1, the most abundant 3'-5' DNA exonuclease in mammals. C-terminal TREX1 variants cause an adult-onset SVD known as retinal vasculopathy with cerebral leukoencephalopathy (RVCL or RVCL-S). In RVCL, an aberrant, C-terminally truncated TREX1 mislocalizes to the nucleus due to deletion of its ER-anchoring domain. Since RVCL pathology mimics that of radiation injury, we reasoned that nuclear TREX1 would cause DNA damage. Here, we show that RVCL-associated TREX1 variants trigger DNA damage in humans, mice, and Drosophila, and that cells expressing RVCL mutant TREX1 are more vulnerable to DNA damage induced by chemotherapy and cytokines that up-regulate TREX1, leading to depletion of TREX1-high cells in RVCL mice. RVCL-associated TREX1 mutants inhibit homology-directed repair (HDR), causing DNA deletions and vulnerablility to PARP inhibitors. In women with RVCL, we observe early-onset breast cancer, similar to patients with BRCA1/2 variants. Our results provide a mechanistic basis linking aberrant TREX1 activity to the DNA damage theory of aging, premature senescence, and microvascular disease.


Asunto(s)
Daño del ADN , Exodesoxirribonucleasas , Fosfoproteínas , Animales , Exodesoxirribonucleasas/genética , Exodesoxirribonucleasas/metabolismo , Humanos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ratones , Reparación del ADN por Recombinación , Fenotipo , Mutación , Drosophila/genética , Envejecimiento/genética , Envejecimiento/metabolismo , Femenino , Drosophila melanogaster/genética , Masculino , Enfermedades de la Retina , Enfermedades Vasculares , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias
3.
Mol Cell Endocrinol ; 592: 112290, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38825223

RESUMEN

Endometriosis is an estrogen-dependent and progesterone-resistant gynecological inflammatory disease of reproductive-age women. Progesterone resistance, loss of progesterone receptor -B (PR-B) in the stromal cells of the endometrium, is one of the hallmarks of endometriosis and a major contributing factor for infertility in endometriosis patients. Loss of PR-B in the stromal cells of the endometriotic lesions poses resistance to the success of progesterone-based therapy. The working hypothesis is that PR-B is hypermethylated and epigenetically silenced, and inhibition of AKT and ERK1/2 pathways will decrease the hypermethylation, reverse the epigenetic silencing, and restore the expression of PR-B via DNA methylation and histone modification mechanisms in the endometriotic lesions. The objectives are to (i) determine the effects of dual inhibition of AKT and ERK1/2 pathways on the expression of PR-B and DNA methylation and histone modification protein machinery in the endometriotic lesions and (ii) identify the underlying epigenetic mechanisms of PR-B restoration in the endometriotic lesions. The results indicate that dual inhibition of AKT and ERK1/2 pathways decreases the hypermethylation, reverses the epigenetic silencing, and restores the expression of PR-B via DNA methylation and H3K9 and H3K27 methylation mechanisms in the endometriotic lesions or endometriotic stromal cells of human origin. These results support the novel concept that restored expression of PR-B in the endometriotic lesions and endometrium may improve the clinical outcome of progesterone therapy in endometriosis patients.

4.
PLoS One ; 19(5): e0299702, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38718044

RESUMEN

Smokers report poorer sleep quality than non-smokers and sleep quality deteriorates further during cessation, increasing risk of smoking relapse. Despite the use of cognitive behavioural therapy for insomnia (CBT-I) to aid quit attempts emerging in the area, little is known about smokers and ex smoker's experiences of sleep during a quit attempt or their perceptions of CBT-I. This study addresses this gap by exploring smoker's and ex-smoker's experiences of the link between smoking and sleep and how this may change as a function of smoking/smoking abstinence. It also explores views of traditional CBT-I components (i.e., perceived feasibility, effectiveness, barriers of use). We conducted semi-structured interviews with current and recently quit smokers (n = 17) between January and September 2022. The framework method was used for analysis. Four themes addressing research questions were described. These included: 1) A viscous cycle; poor sleep quality and negative psychological state during cessation; 2) Perceived engagement and effectiveness; the importance of feasibility, experience, value, identity and psychological state in assessing CBT-I as a cessation tool; 3) Striking a balance; tailoring CBT-I to reduce psychological overload in a time of lifestyle transition; and 4) Personalisation and digital delivery helping overcome psychological barriers during cessation. The analysis suggested during quit attempts smokers experienced a range of sleep problems that could increase risk of relapse due to a negative impact on psychological state. It also revealed participants thought that CBT-I is something they would use during a quit attempt but suggested changes and additions that would improve engagement and be better tailored to quitting smokers. Key additions included the integration of smoking-based cognitive restructuring, starting the intervention prior to a quit attempt, and the need for personalisation and tailoring.


Asunto(s)
Terapia Cognitivo-Conductual , Trastornos del Inicio y del Mantenimiento del Sueño , Cese del Hábito de Fumar , Humanos , Terapia Cognitivo-Conductual/métodos , Masculino , Cese del Hábito de Fumar/psicología , Cese del Hábito de Fumar/métodos , Femenino , Trastornos del Inicio y del Mantenimiento del Sueño/terapia , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Persona de Mediana Edad , Adulto , Fumadores/psicología , Sueño/fisiología , Calidad del Sueño , Investigación Cualitativa
5.
Biochemistry ; 63(10): 1322-1334, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38696389

RESUMEN

Periplasmic solute-binding proteins (SBPs) are key ligand recognition components of bacterial ATP-binding cassette (ABC) transporters that allow bacteria to import nutrients and metabolic precursors from the environment. Periplasmic SBPs comprise a large and diverse family of proteins, of which only a small number have been empirically characterized. In this work, we identify a set of 610 unique uncharacterized proteins within the SBP_bac_5 family that are found in conserved operons comprising genes encoding (i) ABC transport systems and (ii) putative amidases from the FmdA_AmdA family. From these uncharacterized SBP_bac_5 proteins, we characterize a representative periplasmic SBP from Mesorhizobium sp. A09 (MeAmi_SBP) and show that MeAmi_SBP binds l-amino acid amides but not the corresponding l-amino acids. An X-ray crystal structure of MeAmi_SBP bound to l-serinamide highlights the residues that impart distinct specificity for l-amino acid amides and reveals a structural Ca2+ binding site within one of the lobes of the protein. We show that the residues involved in ligand and Ca2+ binding are conserved among the 610 SBPs from experimentally uncharacterized FmdA_AmdA amidase-associated ABC transporter systems, suggesting these homologous systems are also likely to be involved in the sensing, uptake, and metabolism of l-amino acid amides across many Gram-negative nitrogen-fixing soil bacteria. We propose that MeAmi_SBP is involved in the uptake of such solutes to supplement pathways such as the citric acid cycle and the glutamine synthetase-glutamate synthase pathway. This work expands our currently limited understanding of microbial interactions with l-amino acid amides and bacterial nitrogen utilization.


Asunto(s)
Amidas , Proteínas de Unión Periplasmáticas , Amidas/metabolismo , Amidas/química , Cristalografía por Rayos X , Proteínas de Unión Periplasmáticas/metabolismo , Proteínas de Unión Periplasmáticas/química , Proteínas de Unión Periplasmáticas/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/química , Aminoácidos/metabolismo , Mesorhizobium/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Sitios de Unión , Modelos Moleculares , Amidohidrolasas/metabolismo , Amidohidrolasas/química , Calcio/metabolismo , Unión Proteica
6.
Vaccine ; 42(12): 3057-3065, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38584059

RESUMEN

Incarcerated populations experienced high rates of SARS-CoV-2 infection and death during early phases of the COVID-19 pandemic. To evaluate vaccine effectiveness in the carceral context, we investigated the first outbreak of COVID-19 in a California state prison following widespread rollout of vaccines to residents in early 2021. We identified a cohort of 733 state prison residents presumed to be exposed between May 14 and June 22, 2021. 46.9 % (n = 344) were vaccinated, primarily with two doses of mRNA-1273 (n = 332, 93.6 %). In total, 92 PCR-positive cases were identified, of which 14 (14.5 %) occurred among mRNA-1273 vaccinated residents. No cases required hospitalization. All nine isolates collected belonged to the Alpha (B.1.1.7) variant. We used Cox proportional hazard regression to estimate vaccine effectiveness for at least one dose of any vaccine at the start of the outbreak. Vaccine effectiveness was 86 % (95 % CI: 75 %-97 %) against PCR-confirmed infection, with similar results for symptomatic infection. Higher rates of building-level vaccine uptake were associated with a lower overall rate of PCR-confirmed infection and symptomatic infection among unvaccinated residents. Among unvaccinated residents who lived in shared cells at the time of presumed exposure, exposure to a vaccinated cellmate was associated with a 38% (95% CI: 0.37, 1.04) lower hazard rate of PCR-confirmed infection over the study period. In this outbreak involving the Alpha SARS-CoV-2 variant, vaccination conferred direct and possibly indirect protection against SARS-CoV-2 infection and symptomatic COVID-19. Our results support the importance of vaccine uptake in mitigating outbreaks and severe disease in the prison setting and the consideration of community vaccination levels in policy and infection response.


Asunto(s)
COVID-19 , Prisiones , SARS-CoV-2 , Humanos , Vacuna nCoV-2019 mRNA-1273 , Pandemias , Eficacia de las Vacunas , COVID-19/epidemiología , COVID-19/prevención & control , California/epidemiología , Brotes de Enfermedades/prevención & control
7.
Geroscience ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570396

RESUMEN

Small molecule inhibitors of the mitochondrial electron transport chain (ETC) hold significant promise to provide valuable insights to the field of mitochondrial research and aging biology. In this study, we investigated two molecules: mycothiazole (MTZ) - from the marine sponge C. mycofijiensis and its more stable semisynthetic analog 8-O-acetylmycothiazole (8-OAc) as potent and selective chemical probes based on their high efficiency to inhibit ETC complex I function. Similar to rotenone (Rote), MTZ, a newly employed ETC complex I inhibitor, exhibited higher cytotoxicity against cancer cell lines compared to certain non-cancer cell lines. Interestingly, 8-OAc demonstrated greater selectivity for cancer cells when compared to both MTZ and Rote, which has promising potential for anticancer therapeutic development. Furthermore, in vivo experiments with these small molecules utilizing a C. elegans model demonstrate their unexplored potential to investigate aging studies. We observed that both molecules have the ability to induce a mitochondria-specific unfolded protein response (UPRMT) pathway, that extends lifespan of worms when applied in their adult stage. We also found that these two molecules employ different pathways to extend lifespan in worms. Whereas MTZ utilizes the transcription factors ATFS-1 and HSF1, which are involved in the UPRMT and heat shock response (HSR) pathways respectively, 8-OAc only required HSF1 and not ATFS-1 to mediate its effects. This observation underscores the value of applying stable, potent, and selective next generation chemical probes to elucidate an important insight into the functional roles of various protein subunits of ETC complexes and their regulatory mechanisms associated with aging.

8.
Addiction ; 119(6): 1071-1079, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38508212

RESUMEN

AIMS: The study aimed to estimate the impact of introducing a draught alcohol-free beer, thereby increasing the relative availability of these products, on alcohol sales and monetary takings in bars and pubs in England. DESIGN: Randomised crossover field trial. SETTING: England. PARTICIPANTS: Fourteen venues that did not previously sell draught alcohol-free beer. INTERVENTION AND COMPARATOR: Venues completed two intervention periods and two control periods in a randomised order over 8 weeks. Intervention periods involved replacing one draught alcoholic beer with an alcohol-free beer. Control periods operated business as usual. MEASUREMENTS: The primary outcome was mean weekly volume (in litres) of draught alcoholic beer sold. The secondary outcome was mean weekly revenue [in GBP (£)] from all drinks. Analyses adjusted for randomised order, special events, season and busyness. FINDINGS: The adjusted mean difference in weekly sales of draught alcoholic beer was -20 L [95% confidence interval (CI) = -41 to +0.4], equivalent to a 4% reduction (95% CI = 8% reduction to 0.1% increase) in the volume of alcoholic draught beer sold when draught alcohol-free beer was available. Excluding venues that failed at least one fidelity check resulted in an adjusted mean difference of -29 L per week (95% CI = -53 to -5), equivalent to a 5% reduction (95% CI = 8% reduction to 0.8% reduction). The adjusted mean difference in weekly revenue was +61 GBP per week (95% CI = -328 to +450), equivalent to a 1% increase (95% CI = 5% decrease to 7% increase) when draught alcohol-free beer was available. CONCLUSIONS: Introducing a draught alcohol-free beer in bars and pubs in England reduced the volume of draught alcoholic beer sold by 4% to 5%, with no evidence of the intervention impacting net revenue.


Asunto(s)
Consumo de Bebidas Alcohólicas , Cerveza , Comercio , Estudios Cruzados , Humanos , Cerveza/economía , Inglaterra , Consumo de Bebidas Alcohólicas/prevención & control , Restaurantes/economía , Instalaciones Públicas/economía
9.
Proc Natl Acad Sci U S A ; 121(6): e2313661121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38300867

RESUMEN

In the United States, estimates of excess deaths attributable to the COVID-19 pandemic have consistently surpassed reported COVID-19 death counts. Excess deaths reported to non-COVID-19 natural causes may represent unrecognized COVID-19 deaths, deaths caused by pandemic health care interruptions, and/or deaths from the pandemic's socioeconomic impacts. The geographic and temporal distribution of these deaths may help to evaluate which explanation is most plausible. We developed a Bayesian hierarchical model to produce monthly estimates of excess natural-cause mortality for US counties over the first 30 mo of the pandemic. From March 2020 through August 2022, 1,194,610 excess natural-cause deaths occurred nationally [90% PI (Posterior Interval): 1,046,000 to 1,340,204]. A total of 162,886 of these excess natural-cause deaths (90% PI: 14,276 to 308,480) were not reported to COVID-19. Overall, 15.8 excess deaths were reported to non-COVID-19 natural causes for every 100 reported COVID-19 deaths. This number was greater in nonmetropolitan counties (36.0 deaths), the West (Rocky Mountain states: 31.6 deaths; Pacific states: 25.5 deaths), and the South (East South Central states: 26.0 deaths; South Atlantic states: 25.0 deaths; West South Central states: 24.2 deaths). In contrast, reported COVID-19 death counts surpassed estimates of excess natural-cause deaths in metropolitan counties in the New England and Middle Atlantic states. Increases in reported COVID-19 deaths correlated temporally with increases in excess deaths reported to non-COVID-19 natural causes in the same and/or prior month. This suggests that many excess deaths reported to non-COVID-19 natural causes during the first 30 mo of the pandemic in the United States were unrecognized COVID-19 deaths.


Asunto(s)
COVID-19 , Humanos , Estados Unidos/epidemiología , Pandemias , Teorema de Bayes , Causas de Muerte , New England , Mortalidad
10.
J Nucl Med ; 65(1): 100-108, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38050111

RESUMEN

The overexpression of fibroblast activation protein-α (FAP) in solid cancers relative to levels in normal tissues has led to its recognition as a target for delivering agents directly to tumors. Radiolabeled quinoline-based FAP ligands have established clinical feasibility for tumor imaging, but their therapeutic potential is limited due to suboptimal tumor retention, which has prompted the search for alternative pharmacophores. One such pharmacophore is the boronic acid derivative N-(pyridine-4-carbonyl)-d-Ala-boroPro, a potent and selective FAP inhibitor (FAPI). In this study, the diagnostic and therapeutic (theranostic) potential of N-(pyridine-4-carbonyl)-d-Ala-boroPro-based metal-chelating DOTA-FAPIs was evaluated. Methods: Three DOTA-FAPIs, PNT6555, PNT6952, and PNT6522, were synthesized and characterized with respect to potency and selectivity toward soluble and cell membrane FAP; cellular uptake of the Lu-chelated analogs; biodistribution and pharmacokinetics in mice xenografted with human embryonic kidney cell-derived tumors expressing mouse FAP; the diagnostic potential of 68Ga-chelated DOTA-FAPIs by direct organ assay and small-animal PET; the antitumor activity of 177Lu-, 225Ac-, or 161Tb-chelated analogs using human embryonic kidney cell-derived tumors expressing mouse FAP; and the tumor-selective delivery of 177Lu-chelated DOTA-FAPIs via direct organ assay and SPECT. Results: DOTA-FAPIs and their natGa and natLu chelates exhibited potent inhibition of human and mouse sources of FAP and greatly reduced activity toward closely related prolyl endopeptidase and dipeptidyl peptidase 4. 68Ga-PNT6555 and 68Ga-PNT6952 showed rapid renal clearance and continuous accumulation in tumors, resulting in tumor-selective exposure at 60 min after administration. 177Lu-PNT6555 was distinguished from 177Lu-PNT6952 and 177Lu-PNT6522 by significantly higher tumor accumulation over 168 h. In therapeutic studies, all 3 177Lu-DOTA-FAPIs exhibited significant antitumor activity at well-tolerated doses, with 177Lu-PNT6555 producing the greatest tumor growth delay and animal survival. 225Ac-PNT6555 and 161Tb-PNT6555 were similarly efficacious, producing 80% and 100% survival at optimal doses, respectively. Conclusion: PNT6555 has potential for clinical translation as a theranostic agent in FAP-positive cancer.


Asunto(s)
Radioisótopos de Galio , Tomografía de Emisión de Positrones , Humanos , Animales , Ratones , Distribución Tisular , Línea Celular Tumoral , Piridinas
11.
Am J Respir Crit Care Med ; 209(6): 703-715, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-37972349

RESUMEN

Rationale: Acute respiratory distress syndrome (ARDS) has an unacceptably high mortality rate (35%) and is without effective therapy. Orai1 is a Ca2+ channel involved in store-operated Ca2+ entry (SOCE), a process that exquisitely regulates inflammation. Orai1 is considered a druggable target, but no Orai1-specific inhibitors exist to date. Objectives: To evaluate whether ELD607, a first-in-class Orai1 antagonist, can treat ARDS caused by bacterial pneumonia in preclinical models. Methods: ELD607 pharmacology was evaluated in HEK293T cells and freshly isolated immune cells from patients with ARDS. A murine acute lung injury model caused by bacterial pneumonia was then used: mice were infected with Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant S. aureus, or multidrug-resistant P. aeruginosa and then treated with ELD607 intranasally. Measurements and Main Results: ELD607 specifically inhibited SOCE in HEK293T cells with a half-maximal inhibitory concentration of 9 nM. ELD607 was stable in ARDS airway secretions and inhibited SOCE in ARDS immune cells. In vivo, inhaled ELD607 significantly reduced neutrophilia and improved survival. Surprisingly, Orai1 inhibition by ELD607 caused a significant reduction in lung bacteria, including methicillin-resistant S. aureus. ELD607 worked as an immunomodulator that reduced cytokine levels, reduced neutrophilia, and promoted macrophage-mediated resolution of inflammation and clearance of bacteria. Indeed, when alveolar macrophages were depleted with inhaled clodronate, ELD607 was no longer able to resolve inflammation or clear bacteria. Conclusions: These data indicate that specific Orai1 inhibition by ELD607 may be a novel approach to reduce multiorgan inflammation and treat antibiotic-resistant bacteria.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neumonía Bacteriana , Síndrome de Dificultad Respiratoria , Humanos , Ratones , Animales , Canales de Calcio/metabolismo , Canales de Calcio/farmacología , Calcio/metabolismo , Células HEK293 , Staphylococcus aureus Resistente a Meticilina/metabolismo , Señalización del Calcio , Inflamación/tratamiento farmacológico , Pulmón/metabolismo , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Neumonía Bacteriana/tratamiento farmacológico , Proteína ORAI1/metabolismo , Proteína ORAI1/farmacología
12.
Adv Sci (Weinh) ; 11(2): e2304449, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37974523

RESUMEN

Developing practical quantum technologies will require the exquisite manipulation of fragile systems in a robust and repeatable way. As quantum technologies move toward real world applications, from biological sensing to communication in space, increasing experimental complexity introduces constraints that can be alleviated by the introduction of new technologies. Robotics has shown tremendous progress in realizing increasingly smart, autonomous, and highly dexterous machines. Here, a robotic arm equipped with a magnet is demonstrated to sensitize an NV center quantum magnetometer in challenging conditions unachievable with standard techniques. Vector magnetic fields are generated with 1° angular and 0.1 mT amplitude accuracy and determine the orientation of a single stochastically-aligned spin-based sensor in a constrained physical environment. This work opens up the prospect of integrating robotics across many quantum degrees of freedom in constrained settings, allowing for increased prototyping speed, control, and robustness in quantum technology applications.

13.
Reprod Toxicol ; 123: 108492, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37931768

RESUMEN

Hexavalent chromium, Cr(VI), is a heavy metal endocrine disruptor used widely in various industries worldwide and is considered a reproductive toxicant. Our previous studies demonstrated that lactational exposure to Cr(VI) caused follicular atresia, disrupted steroid hormone biosynthesis and signaling, and delayed puberty. However, the underlying mechanism was unknown. The current study investigated the effects of Cr(VI) exposure (25 ppm) during postnatal days 1-21 via dam's milk on epigenetic alterations in the ovary of F1 offspring. Data indicated that Cr(VI) disrupted follicle development and caused apoptosis by increasing DNMT3a /3b and histone methyl marks (H3K27me3 and H3K9me3) along with decreasing histone acetylation marks (H3K9ac and H3K27ac). Our study demonstrates that exposure to Cr(VI) causes changes in the epigenetic marks, partially contributing to the transcriptional repression of genes regulating ovarian development, cell proliferation (PCNA), cell survival (BCL-XL and BCL-2), and activation of genes regulating apoptosis (AIF and cleaved caspase-3), resulting in follicular atresia. The current study suggests a role for epigenetics in Cr(VI)-induced ovotoxicity and infertility.


Asunto(s)
Histonas , Ovario , Femenino , Humanos , Atresia Folicular , Cromo/toxicidad , Apoptosis , Epigénesis Genética
14.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-37950875

RESUMEN

We recently showed that transcranial alternating current stimulation of the dorsolateral prefrontal cortex modulates spontaneous bursts of muscle sympathetic nerve activity, heart rate, and blood pressure (Sesa-Ashton G, Wong R, McCarthy B, Datta S, Henderson LA, Dawood T, Macefield VG. Stimulation of the dorsolateral prefrontal cortex modulates muscle sympathetic nerve activity and blood pressure in humans. Cereb Cortex Comm. 2022:3:2tgac017.). Stimulation was delivered between scalp electrodes placed over the nasion and electroencephalogram (EEG) electrode site F3 (left dorsolateral prefrontal cortex) or F4 (right dorsolateral prefrontal cortex), and therefore the current passed within the anatomical locations underlying the left and right ventromedial prefrontal cortices. Accordingly, we tested the hypothesis that stimulation of the left and right ventromedial prefrontal cortices would also modulate muscle sympathetic nerve activity, although we predicted that this would be weaker than that seen during dorsolateral prefrontal cortex stimulation. We further tested whether stimulation of the right ventromedial prefrontal cortices would cause greater modulation of muscle sympathetic nerve activity, than stimulation of the left ventromedial prefrontal cortices. In 11 individuals, muscle sympathetic nerve activity was recorded via microelectrodes inserted into the right common peroneal nerve, together with continuous blood pressure, electrocardiogram, and respiration. Stimulation was achieved using transcranial alternating current stimulation, +2 to -2 mA, 0.08 Hz, 100 cycles, applied between electrodes placed over the nasion, and EEG electrode site FP1, (left ventromedial prefrontal cortices) or FP2 (right ventromedial prefrontal cortices); for comparison, stimulation was also applied over F4 (right dorsolateral prefrontal cortex). Stimulation of all three cortical sites caused partial entrainment of muscle sympathetic nerve activity to the sinusoidal stimulation, together with modulation of blood pressure and heart rate. We found a significant fall in mean blood pressure of ~6 mmHg (P = 0.039) during stimulation of the left ventromedial prefrontal cortices, as compared with stimulation of the right. We have shown, for the first time, that transcranial alternating current stimulation of the ventromedial prefrontal cortices modulates muscle sympathetic nerve activity and blood pressure in awake humans at rest. However, it is unclear if this modulation occurred through the same brain pathways activated during transcranial alternating current stimulation of the dorsolateral prefrontal cortex.


Asunto(s)
Corteza Prefrontal , Estimulación Transcraneal de Corriente Directa , Humanos , Presión Sanguínea/fisiología , Corteza Prefrontal/fisiología , Encéfalo , Estimulación Eléctrica , Músculos
15.
bioRxiv ; 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38077060

RESUMEN

Small molecule inhibitors of the mitochondrial electron transport chain (ETC) hold significant promise to provide valuable insights to the field of mitochondrial research and aging biology. In this study, we investigated two molecules: mycothiazole (MTZ) - from the marine sponge C. mycofijiensis and its more stable semisynthetic analog 8-O-acetylmycothiazole (8-OAc) as potent and selective chemical probes based on their high efficiency to inhibit ETC complex I function. Similar to rotenone (Rote), a widely used ETC complex I inhibitor, these two molecules showed cytotoxicity to cancer cells but strikingly demonstrate a lack of toxicity to non-cancer cells, a highly beneficial feature in the development of anti-cancer therapeutics. Furthermore, in vivo experiments with these small molecules utilizing C.elegans model demonstrate their unexplored potential to investigate aging studies. We observed that both molecules have the ability to induce a mitochondria-specific unfolded protein response (UPRMT) pathway, that extends lifespan of worms when applied in their adult stage. Interestingly, we also found that these two molecules employ different pathways to extend lifespan in worms. Whereas MTZ utilize the transcription factors ATFS-1 and HSF-1, which are involved in the UPRMT and heat shock response (HSR) pathways respectively, 8-OAc only required HSF-1 and not ATFS-1 to mediate its effects. This observation underscores the value of applying stable, potent, and selective next generation chemical probes to elucidate an important insight into the functional roles of various protein subunits of ETC complexes and their regulatory mechanisms associated with aging.

16.
Nicotine Tob Res ; 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996095

RESUMEN

BACKGROUND: Smokers report poorer sleep than non-smokers and sleep quality deteriorates further during cessation, increasing risk of smoking relapse. Better understanding of the relationship between sleep and relapse-related outcomes could inform novel approaches to smoking cessation support. The aim of this study was to investigate same day associations of self-reported sleep quality and fatigue severity with factors associated with successful cessation and cessation beliefs, among regular smokers. METHODS: This cross-sectional observational study (n=412) collected self-reported sleep quality, fatigue severity, and factors associated with successful cessation and cessation beliefs among regular smokers via an online survey (60% male). RESULTS: There was evidence of an association between sleep quality (SQ) and reduced 24hr (ß = -0.12, p = 0.05) and lifetime (ß = -0.09, p = 0.04) abstinence self-efficacy. In addition, poorer SQ and higher fatigue severity (FS) were associated with increased smoking urges (SQ: ß = 0.27, p < .001; FS: ß = 0.32, p < .001), increased barriers to cessation (SQ: ß = 0.19, p < .001; FS: ß = 0.32, p < .001), and increased perceived risks to cessation (SQ: ß = 0.18, p < .001; FS: ß = 0.26, p < .001). Fatigue severity was weakly associated with increased perceived benefits to cessation (ß = 0.12, p = .017). CONCLUSIONS: Self-reported sleep quality and fatigue severity were associated with multiple factors associated with successful cessation and cessation beliefs. Further research is needed to extend these findings by using different methods to identify the temporal direction of associations and causality. IMPLICATIONS: This study is the first to examine associations between sleep quality, fatigue severity, and factors associated with successful cessation and cessation beliefs. Findings show that both sleep quality and fatigue severity are associated with multiple factors associated with successful cessation and could be modifiable targets for future smoking cessation interventions. Furthermore, our data suggest that fatigue severity has an independent effect on multiple factors associated with successful cessation when accounting for sleep quality. This indicates that fatigue, independent of sleep quality, could be an important factor in a quit attempt.

17.
Acta Pharm Sin B ; 13(8): 3561-3574, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37655329

RESUMEN

WS9326A is a peptide antibiotic containing a highly unusual N-methyl-E-2-3-dehydrotyrosine (NMet-Dht) residue that is incorporated during peptide assembly on a non-ribosomal peptide synthetase (NRPS). The cytochrome P450 encoded by sas16 (P450Sas) has been shown to be essential for the formation of the alkene moiety in NMet-Dht, but the timing and mechanism of the P450Sas-mediated α,ß-dehydrogenation of Dht remained unclear. Here, we show that the substrate of P450Sas is the NRPS-associated peptidyl carrier protein (PCP)-bound dipeptide intermediate (Z)-2-pent-1'-enyl-cinnamoyl-Thr-N-Me-Tyr. We demonstrate that P450Sas-mediated incorporation of the double bond follows N-methylation of the Tyr by the N-methyl transferase domain found within the NRPS, and further that P450Sas appears to be specific for substrates containing the (Z)-2-pent-1'-enyl-cinnamoyl group. A crystal structure of P450Sas reveals differences between P450Sas and other P450s involved in the modification of NRPS-associated substrates, including the substitution of the canonical active site alcohol residue with a phenylalanine (F250), which in turn is critical to P450Sas activity and WS9326A biosynthesis. Together, our results suggest that P450Sas catalyses the direct dehydrogenation of the NRPS-bound dipeptide substrate, thus expanding the repertoire of P450 enzymes that can be used to produce biologically active peptides.

18.
ACS Photonics ; 10(9): 3302-3309, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37743942

RESUMEN

Diamond color centers are promising optically addressable solid-state spins that can be matter-qubits, mediate deterministic interaction between photons, and act as single photon emitters. Useful quantum computers will comprise millions of logical qubits. To become useful in constructing quantum computers, spin-photon interfaces must, therefore, become scalable and be compatible with mass-manufacturable photonics and electronics. Here, we demonstrate the heterogeneous integration of NV centers in nanodiamond with low-fluorescence silicon nitride photonics from a standard 180 nm CMOS foundry process. Nanodiamonds are positioned over predefined sites in a regular array on a waveguide in a single postprocessing step. Using an array of optical fibers, we excite NV centers selectively from an array of six integrated nanodiamond sites and collect the photoluminescence (PL) in each case into waveguide circuitry on-chip. We verify single photon emission by an on-chip Hanbury Brown and Twiss cross-correlation measurement, which is a key characterization experiment otherwise typically performed routinely with discrete optics. Our work opens up a simple and effective route to simultaneously address large arrays of individual optically active spins at scale, without requiring discrete bulk optical setups. This is enabled by the heterogeneous integration of NV center nanodiamonds with CMOS photonics.

19.
Zookeys ; 1168: 1-10, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37397800

RESUMEN

A new species, Hypothycerayi MacGown & Hill, sp. nov. (Coleoptera: Scarabaeidae: Melolonthinae: Melolonthini), is described from east central Alabama, USA. Three other species of Hypothyce, H.burnei Skelley, H.mixta Howden and H.osburni (Cartwright) are known to occur in the United States. We discuss differences between these species and provide an updated identification key to the genus.

20.
Cell ; 186(17): 3642-3658.e32, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37437570

RESUMEN

A system for programmable export of RNA molecules from living cells would enable both non-destructive monitoring of cell dynamics and engineering of cells capable of delivering executable RNA programs to other cells. We developed genetically encoded cellular RNA exporters, inspired by viruses, that efficiently package and secrete cargo RNA molecules from mammalian cells within protective nanoparticles. Exporting and sequencing RNA barcodes enabled non-destructive monitoring of cell population dynamics with clonal resolution. Further, by incorporating fusogens into the nanoparticles, we demonstrated the delivery, expression, and functional activity of exported mRNA in recipient cells. We term these systems COURIER (controlled output and uptake of RNA for interrogation, expression, and regulation). COURIER enables measurement of cell dynamics and establishes a foundation for hybrid cell and gene therapies based on cell-to-cell delivery of RNA.


Asunto(s)
Técnicas Citológicas , Técnicas Genéticas , ARN , Animales , Transporte Biológico , Mamíferos/metabolismo , ARN/genética , ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Virus/genética , Tipificación Molecular , Análisis de Secuencia de ARN
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