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1.
Nature ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961286

RESUMO

Current hypotheses of early tetrapod evolution posit close ecological and biogeographic ties to the extensive coal-producing wetlands of the Carboniferous palaeoequator with rapid replacement of archaic tetrapod groups by relatives of modern amniotes and lissamphibians in the late Carboniferous (about 307 million years ago). These hypotheses draw on a tetrapod fossil record that is almost entirely restricted to palaeoequatorial Pangea (Laurussia)1,2. Here we describe a new giant stem tetrapod, Gaiasia jennyae, from high-palaeolatitude (about 55° S) early Permian-aged (about 280 million years ago) deposits in Namibia that challenges this scenario. Gaiasia is represented by several large, semi-articulated skeletons characterized by a weakly ossified skull with a loosely articulated palate dominated by a broad diamond-shaped parasphenoid, a posteriorly projecting occiput, and enlarged, interlocking dentary and coronoid fangs. Phylogenetic analysis resolves Gaiasia within the tetrapod stem group as the sister taxon of the Carboniferous Colosteidae from Euramerica. Gaiasia is larger than all previously described digited stem tetrapods and provides evidence that continental tetrapods were well established in the cold-temperate latitudes of Gondwana during the final phases of the Carboniferous-Permian deglaciation. This points to a more global distribution of continental tetrapods during the Carboniferous-Permian transition and indicates that previous hypotheses of global tetrapod faunal turnover and dispersal at this time2,3 must be reconsidered.

2.
Nature ; 610(7932): 467-471, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198793

RESUMO

Of more than a thousand known cataclysmic variables (CVs), where a white dwarf is accreting from a hydrogen-rich star, only a dozen have orbital periods below 75 minutes1-9. One way to achieve these short periods requires the donor star to have undergone substantial nuclear evolution before interacting with the white dwarf10-14, and it is expected that these objects will transition to helium accretion. These transitional CVs have been proposed as progenitors of helium CVs13-18. However, no known transitional CV is expected to reach an orbital period short enough to account for most of the helium CV population, leaving the role of this evolutionary pathway unclear. Here we report observations of ZTF J1813+4251, a 51-minute-orbital-period, fully eclipsing binary system consisting of a star with a temperature comparable to that of the Sun but a density 100 times greater owing to its helium-rich composition, accreting onto a white dwarf. Phase-resolved spectra, multi-band light curves and the broadband spectral energy distribution allow us to obtain precise and robust constraints on the masses, radii and temperatures of both components. Evolutionary modelling shows that ZTF J1813+4251 is destined to become a helium CV binary, reaching an orbital period under 20 minutes, rendering ZTF J1813+4251 a previously missing link between helium CV binaries and hydrogen-rich CVs.

3.
Nature ; 595(7865): 39-42, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34194021

RESUMO

White dwarfs represent the last stage of evolution of stars with mass less than about eight times that of the Sun and, like other stars, are often found in binaries1,2. If the orbital period of the binary is short enough, energy losses from gravitational-wave radiation can shrink the orbit until the two white dwarfs come into contact and merge3. Depending on the component masses, the merger can lead to a supernova of type Ia or result in a massive white dwarf4. In the latter case, the white dwarf remnant is expected to be highly magnetized5,6 because of the strong magnetic dynamo that should arise during the merger, and be rapidly spinning from the conservation of the orbital angular momentum7. Here we report observations of a white dwarf, ZTF J190132.9+145808.7, that exhibits these properties, but to an extreme: a rotation period of 6.94 minutes, a magnetic field ranging between 600 megagauss and 900 megagauss over its surface, and a stellar radius of [Formula: see text] kilometres, only slightly larger than the radius of the Moon. Such a small radius implies that the star's mass is close to the maximum white dwarf mass, or Chandrasekhar mass. ZTF J190132.9+145808.7 is likely to be cooling through the Urca processes (neutrino emission from electron capture on sodium) because of the high densities reached in its core.

4.
Proc Natl Acad Sci U S A ; 121(29): e2313370121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38985769

RESUMO

Heat Shock Factor 1 (HSF1) is best known as the master transcriptional regulator of the heat-shock response (HSR), a conserved adaptive mechanism critical for protein homeostasis (proteostasis). Combining a genome-wide RNAi library with an HSR reporter, we identified Jumonji domain-containing protein 6 (JMJD6) as an essential mediator of HSF1 activity. In follow-up studies, we found that JMJD6 is itself a noncanonical transcriptional target of HSF1 which acts as a critical regulator of proteostasis. In a positive feedback circuit, HSF1 binds and promotes JMJD6 expression, which in turn reduces heat shock protein 70 (HSP70) R469 monomethylation to disrupt HSP70-HSF1 repressive complexes resulting in enhanced HSF1 activation. Thus, JMJD6 is intricately wired into the proteostasis network where it plays a critical role in cellular adaptation to proteotoxic stress.


Assuntos
Proteínas de Choque Térmico HSP70 , Fatores de Transcrição de Choque Térmico , Resposta ao Choque Térmico , Histona Desmetilases com o Domínio Jumonji , Proteostase , Humanos , Fatores de Transcrição de Choque Térmico/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteostase/fisiologia , Retroalimentação Fisiológica , Adaptação Fisiológica , Células HEK293 , Estresse Proteotóxico
5.
Proc Natl Acad Sci U S A ; 120(17): e2217396120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068235

RESUMO

Octopamine is a well-established invertebrate neurotransmitter involved in fight or flight responses. In mammals, its function was replaced by epinephrine. Nevertheless, it is present at trace amounts and can modulate the release of monoamine neurotransmitters by a yet unidentified mechanism. Here, through a multidisciplinary approach utilizing in vitro and in vivo models of α-synucleinopathy, we uncovered an unprecedented role for octopamine in driving the conversion from toxic to neuroprotective astrocytes in the cerebral cortex by fostering aerobic glycolysis. Physiological levels of neuron-derived octopamine act on astrocytes via a trace amine-associated receptor 1-Orai1-Ca2+-calcineurin-mediated signaling pathway to stimulate lactate secretion. Lactate uptake in neurons via the monocarboxylase transporter 2-calcineurin-dependent pathway increases ATP and prevents neurodegeneration. Pathological increases of octopamine caused by α-synuclein halt lactate production in astrocytes and short-circuits the metabolic communication to neurons. Our work provides a unique function of octopamine as a modulator of astrocyte metabolism and subsequent neuroprotection with implications to α-synucleinopathies.


Assuntos
Octopamina , alfa-Sinucleína , Animais , alfa-Sinucleína/metabolismo , Astrócitos/metabolismo , Calcineurina/metabolismo , Lactatos/metabolismo , Mamíferos/metabolismo , Neuroproteção , Neurotransmissores/metabolismo , Octopamina/metabolismo
6.
Nature ; 571(7766): 528-531, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31341301

RESUMO

General relativity1 predicts that short-orbital-period binaries emit considerable amounts of gravitational radiation. The upcoming Laser Interferometer Space Antenna2 (LISA) is expected to detect tens of thousands of such systems3 but few have been identified4, of which only one5 is eclipsing-the double-white-dwarf binary SDSS J065133.338+284423.37, which has an orbital period of 12.75 minutes. Here we report the discovery of an eclipsing double-white-dwarf binary system, ZTF J153932.16+502738.8, with an orbital period of 6.91 minutes. This system has an orbit so compact that the entire binary could fit within the diameter of the planet Saturn. The system exhibits a deep eclipse, and a double-lined spectroscopic nature. We see rapid orbital decay, consistent with that expected from general relativity. ZTF J153932.16+502738.8 is a strong source of gravitational radiation close to the peak of LISA's sensitivity, and we expect it to be detected within the first week of LISA observations, once LISA launches in approximately 2034.

7.
Proc Natl Acad Sci U S A ; 119(27): e2111262119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35776542

RESUMO

All cells contain specialized signaling pathways that enable adaptation to specific molecular stressors. Yet, whether these pathways are centrally regulated in complex physiological stress states remains unclear. Using genome-scale fitness screening data, we quantified the stress phenotype of 739 cancer cell lines, each representing a unique combination of intrinsic tumor stresses. Integrating dependency and stress perturbation transcriptomic data, we illuminated a network of genes with vital functions spanning diverse stress contexts. Analyses for central regulators of this network nominated C16orf72/HAPSTR1, an evolutionarily ancient gene critical for the fitness of cells reliant on multiple stress response pathways. We found that HAPSTR1 plays a pleiotropic role in cellular stress signaling, functioning to titrate various specialized cell-autonomous and paracrine stress response programs. This function, while dispensable to unstressed cells and nematodes, is essential for resilience in the presence of stressors ranging from DNA damage to starvation and proteotoxicity. Mechanistically, diverse stresses induce HAPSTR1, which encodes a protein expressed as two equally abundant isoforms. Perfectly conserved residues in a domain shared between HAPSTR1 isoforms mediate oligomerization and binding to the ubiquitin ligase HUWE1. We show that HUWE1 is a required cofactor for HAPSTR1 to control stress signaling and that, in turn, HUWE1 feeds back to ubiquitinate and destabilize HAPSTR1. Altogether, we propose that HAPSTR1 is a central rheostat in a network of pathways responsible for cellular adaptability, the modulation of which may have broad utility in human disease.


Assuntos
Dano ao DNA , Aptidão Genética , Proteínas Nucleares , Estresse Fisiológico , Motivos de Aminoácidos , Animais , Linhagem Celular Tumoral , Sequência Conservada , Dano ao DNA/genética , Humanos , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Domínios Proteicos , Transdução de Sinais/genética , Estresse Fisiológico/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
8.
J Clin Microbiol ; 62(4): e0129623, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38456690

RESUMO

Early initiation of antimicrobial therapy targeting resistant bacterial pathogens causing sepsis and bloodstream infections (BSIs) is critical for a successful outcome. The T2Resistance Panel (T2R) detects the following resistance genes within organisms that commonly cause BSIs directly from patient blood samples: blaKPC, blaCTXM-14/15, blaNDM/bla/IMP/blaVIM, blaAmpC, blaOXA, vanA, vanB, and mecA/mecC. We conducted a prospective study in two major medical centers for the detection of circulating resistance genes by T2R in patients with BSIs. T2R reports were compared to antimicrobial susceptibility testing (AST), phenotypic identification, and standard molecular detection assays. Among 59 enrolled patients, 25 resistance genes were identified: blaKPC (n = 10), blaNDM/bla/IMP/blaVIM (n = 5), blaCTXM-14/15 (n = 4), blaAmpC (n = 2), and mecA/mecC (n = 4). Median time-to-positive-T2R in both hospitals was 4.4 hours [interquartile range (IQR): 3.65-4.97 hours] in comparison to that for positive blood cultures with final reporting of AST of 58.34 h (IQR: 45.51-111.2 hours; P < 0.0001). The sensitivity of T2R to detect the following genes in comparison to AST was 100% for blaCTXM-14/15, blaNDM/bla/IMP/blaVIM, blaAmpC, mecA/mecC and 87.5% for blaKPC. When monitored for the impact of significant antimicrobial changes, there were 32 events of discontinuation of unnecessary antibiotics and 17 events of escalation of antibiotics, including initiation of ceftazidime/avibactam in six patients in response to positive T2R results for blaKPC. In summary, T2R markers were highly sensitive for the detection of drug resistance genes in patients with bacterial BSIs, when compared with standard molecular resistance detection systems and phenotypic identification assays while significantly reducing by approximately 90% the time to detection of resistance compared to standard methodology and impacting clinical decisions for antimicrobial therapy. IMPORTANCE: This is the first reported study to our knowledge to identify key bacterial resistance genes directly from the bloodstream within 3 to 5 hours in patients with bloodstream infections and sepsis. The study further demonstrated a direct effect in modifying initial empirical antibacterial therapy in response to T2R signal to treat resistant bacteria causing bloodstream infections and sepsis.


Assuntos
Anti-Infecciosos , Bacteriemia , Infecções Bacterianas , Sepse , Humanos , Estudos Prospectivos , Bacteriemia/microbiologia , Projetos Piloto , Bactérias/genética , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
9.
J Anat ; 244(6): 1093-1101, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38267217

RESUMO

The etiology of sirenomelia is currently unknown. Data are limited in comparing external and internal abnormalities using modern imaging technologies and molecular genetic analysis. The purpose of the current study was designed to compare external and internal anatomical defects in two cases of sirenomelia and Potter's sequence. Considered rare, Potter's sequence is a fetal disorder with characteristic features of bilateral renal agenesis, obstructive uropathy, atypical facial appearance, and limb malformations. The internal and external malformations of two term fetuses with sirenomelia and Potter's sequence were compared using assessment of external features, radiography and MRI on internal structures, and molecular genetic studies on sex determination. Data reveal that both fetuses were male and manifested with an overlapping but distinct spectrum of abnormalities. Principal differences were noted in the development of the ears, brain, urogenital system, lower limbs, pelvis, and vertebral column. Defects of the axial mesoderm are likely to underlie the abnormalities seen in both fetuses. The first one, which had only caudal defects, was found to have a spectrum of abnormalities most similar to those associated with more severe forms of the small pelvic outlet syndrome, although the structure and orientation of the sacrum and iliae were different from previously reported cases. The other had both caudal and cranial defects, and was most similar to those described in the axial mesodermal dysplasia syndrome. Defects associated with sirenomelia can be evaluated with standard gross anatomy examination, radiology, MRI, and modified PCR techniques to determine anatomical abnormalities and the sex of preserved specimens, respectively. Evidence indicated that sirenomelia could be developed via various etiologies.


Assuntos
Ectromelia , Humanos , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/diagnóstico por imagem , Ectromelia/genética , Ectromelia/diagnóstico por imagem , Ectromelia/patologia , Feto/anormalidades , Feto/diagnóstico por imagem , Imageamento por Ressonância Magnética
10.
Am J Obstet Gynecol ; 230(5): 473-475, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38431464

RESUMO

Ninety-four percent of global maternal deaths occur in low- and middle-income countries (LMICs). The UN has a goal of reducing maternal deaths to <70 per 100,000 live births by 2030, but progress is minimal. Maternal deaths in LMICs are associated with 3 delays in the care of women with obstetrical emergencies: 1) in the family of the woman realizing that her life is at risk, 2) in the transport of the woman to a hospital, and 3) in providing care after arrival at the hospital. These 3 delays function like links in a chain, and failure of any link leads to maternal death. LMICs have characteristics that make it likely that the chain will break. Women in LMICs frequently have low standing, and cultural beliefs often lead to delay in the recognition of obstetrical emergencies. LMICs are characterized by poor roads and long distances to hospitals leading to transport delays. Cultural and other factors also lead to treatment delays when a woman reaches a suitably-equipped and staffed hospital. Nepal has addressed these delays and reduced maternal mortality. Firstly, we have reported in the Journal the use of culturally acceptable approaches to improving the knowledge about antenatal care in remote villages. In the case of Nepal, singing songs related to maternal care proved to be a highly effective strategy. We now report that the government of Nepal has repurposed military helicopters to overcome the tyranny of poor roads to allow rapid transport of women with obstetrical emergencies to a small number of fully-equipped and staffed hospitals. As of June 2023, this service has successfully retrieved 625 women in four and half years. The Nepalese government has included questions on maternal mortality in the 2021 national census, followed by a verbal autopsy. These data indicate a fall in the maternal mortality ratio from 239 in 2016 to 151 in 2021. The efficiency of the triage service continues to improve, suggesting that maternal mortality will continue to fall. This may provide a model that can be implemented in other LMICs and highlights factors that may be responsible for recent increases in the US maternal mortality ratio.


Assuntos
Países em Desenvolvimento , Mortalidade Materna , Humanos , Nepal/epidemiologia , Feminino , Gravidez , Resgate Aéreo , Tempo para o Tratamento , Complicações na Gravidez/mortalidade
11.
Proc Natl Acad Sci U S A ; 118(17)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33875588

RESUMO

Earth's largest biotic crisis occurred during the Permo-Triassic Transition (PTT). On land, this event witnessed a turnover from synapsid- to archosauromorph-dominated assemblages and a restructuring of terrestrial ecosystems. However, understanding extinction patterns has been limited by a lack of high-precision fossil occurrence data to resolve events on submillion-year timescales. We analyzed a unique database of 588 fossil tetrapod specimens from South Africa's Karoo Basin, spanning ∼4 My, and 13 stratigraphic bin intervals averaging 300,000 y each. Using sample-standardized methods, we characterized faunal assemblage dynamics during the PTT. High regional extinction rates occurred through a protracted interval of ∼1 Ma, initially co-occurring with low origination rates. This resulted in declining diversity up to the acme of extinction near the Daptocephalus-Lystrosaurus declivis Assemblage Zone boundary. Regional origination rates increased abruptly above this boundary, co-occurring with high extinction rates to drive rapid turnover and an assemblage of short-lived species symptomatic of ecosystem instability. The "disaster taxon" Lystrosaurus shows a long-term trend of increasing abundance initiated in the latest Permian. Lystrosaurus comprised 54% of all specimens by the onset of mass extinction and 70% in the extinction aftermath. This early Lystrosaurus abundance suggests its expansion was facilitated by environmental changes rather than by ecological opportunity following the extinctions of other species as commonly assumed for disaster taxa. Our findings conservatively place the Karoo extinction interval closer in time, but not coeval with, the more rapid marine event and reveal key differences between the PTT extinctions on land and in the oceans.


Assuntos
Extinção Biológica , Fósseis , Animais , Biodiversidade , Ecossistema , África do Sul
12.
J Strength Cond Res ; 38(1): 30-37, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815253

RESUMO

ABSTRACT: Merrigan, JJ, Strang, A, Eckerle, J, Mackowski, N, Hierholzer, K, Ray, NT, Smith, R, Hagen, JA, and Briggs, RA. Countermovement jump force-time curve analyses: reliability and comparability across force plate systems. J Strength Cond Res 38(1): 30-37, 2024-Considering the growing prevalence of commercial force plates providing automated force-time analyses, understanding levels of agreement across force plate systems is warranted. Countermovement jump (CMJ) metrics across Vald ForceDecks (FD), Hawkin Dynamics (HD), and Sparta Science (SS) force plate systems were compared. Twenty-two subjects completed CMJ testing (∼128 comparisons) on each force plate system separately with rest between jumps. Baseline testing occurred 3 times and demonstrated poor test-retest reliability for modified reactive strength index (mRSI) and rate of force development (RFD). ForceDecks and HD comparisons yielded acceptable agreement for concentric/propulsive relative force and net impulse, jump height, eccentric/braking RFD, and mRSI, but systematic and proportionate bias existed for RFD. Sparta Science jump height and reactive strength index (RSI) demonstrated systematic overestimations compared with HD and FD, but jump height had acceptable agreement according to concordance correlation coefficients (CCC = 0.92-0.95). Agreement between SS load (eccentric RFD) and HD braking RFD was acceptable (CCC = 0.91), whereas agreement between SS load and FD deceleration RFD was considered acceptable (CCC = 0.81-0.87) but demonstrated systematic and proportionate bias. ForceDecks (CCC = 0.89) and HD (CCC = 0.85) average relative concentric/propulsive force yielded acceptable agreement with SS explode (average relative concentric force), but SS explode demonstrated systematically lower values than FD and HD. Sparta Science drive (concentric impulse) yielded acceptable agreement with HD relative propulsive impulse (CCC = 0.85), but not FD concentric impulse. Human performance practitioners need to be aware of inconsistencies among testing procedures and analyses across force plate systems, such as differences in metric definitions and units of measurement, before making comparisons across systems.


Assuntos
Força Muscular , Humanos , Reprodutibilidade dos Testes
13.
Cell Tissue Res ; 391(3): 523-544, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36543895

RESUMO

Tendon injuries occur commonly in both human and equine athletes, and poor tendon regeneration leads to functionally deficient scar tissue and an increased frequency of re-injury. Despite evidence suggesting inadequate resolution of inflammation leads to fibrotic healing, our understanding of the inflammatory pathways implicated in tendinopathy remains poorly understood, meaning successful targeted treatments are lacking. Here, we demonstrate IL-1ß, TNFα and IFN-γ work synergistically to induce greater detrimental consequences for equine tenocytes than when used individually. This includes altering tendon associated and matrix metalloproteinase gene expression and impairing the cells' ability to contract a 3-D collagen gel, a culture technique which more closely resembles the in vivo environment. Moreover, these adverse effects cannot be rescued by direct suppression of IL-1ß using IL-1RA or factors produced by BM-MSCs. Furthermore, we provide evidence that NF-κB, but not JNK, P38 MAPK or STAT 1, is translocated to the nucleus and able to bind to DNA in tenocytes following TNFα and IL-1ß stimulation, suggesting this signalling cascade may be responsible for the adverse downstream consequences of these inflammatory cytokines. We suggest a superior approach for treatment of tendinopathy may therefore be to target specific signalling pathways such as NF-κB.


Assuntos
Células-Tronco Mesenquimais , Tendinopatia , Humanos , Animais , Cavalos , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-1beta/metabolismo , NF-kappa B/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interferon gama/metabolismo , Tenócitos/metabolismo , Tendinopatia/metabolismo , Células Cultivadas
14.
Reproduction ; 166(2): R25-R38, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37318094

RESUMO

In brief: Placental oxidative stress contributes to both normal and abnormal placentation during pregnancy. This review discusses the potential consequence of oxidative stress-induced placental dysfunction on pregnancies complicated by fetal death and pregnancies with a high risk of fetal death. Abstract: The placenta is a source of reactive oxygen free radicals due to the oxidative metabolism required to meet the demands of the growing fetus. The placenta has an array of efficient antioxidant defense systems to deal with rising oxidative stress created by free radicals during pregnancy. Properly controlled physiological (low-level) free radical production is a necessary part of cellular signaling pathways and downstream activities during normal placental development; however, poorly controlled oxidative stress can cause aberrant placentation, immune disturbances and placental dysfunction. Abnormal placental function and immune disturbances are linked to many pregnancy-related disorders, including early and recurrent pregnancy loss, fetal death, spontaneous preterm birth, preeclampsia and fetal growth restriction. This review discusses the role of placental oxidative stress in both normal and pathological settings. Finally, based on previously published work, this review presents multiple lines of evidence for the strong association between oxidative stress and adverse pregnancy outcomes, including fetal death and pregnancies with a high risk of fetal death.


Assuntos
Doenças Placentárias , Pré-Eclâmpsia , Complicações na Gravidez , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Placenta/metabolismo , Nascimento Prematuro/metabolismo , Placentação , Estresse Oxidativo/fisiologia , Complicações na Gravidez/metabolismo , Doenças Placentárias/metabolismo , Morte Fetal/etiologia , Pré-Eclâmpsia/metabolismo , Retardo do Crescimento Fetal/metabolismo
15.
Am J Obstet Gynecol ; 228(3): 330.e1-330.e18, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36002050

RESUMO

BACKGROUND: The onset of preterm labor is associated with inflammation. Previous studies suggested that this is distinct from the inflammation observed during term labor. Our previous work on 44 genes differentially expressed in myometria in term labor demonstrated a different pattern of gene expression from that observed in preterm laboring and nonlaboring myometria. We found increased expression of inflammatory genes in preterm labor associated with chorioamnionitis, but in the absence of chorioamnionitis observed no difference in gene expression in preterm myometria regardless of laboring status, suggesting that preterm labor is associated with different myometrial genes or signals originating from outside the myometrium. Given that a small subset of genes were assessed, this study aimed to use RNA sequencing and bioinformatics to assess the myometrial transcriptome during preterm labor in the presence and absence of chorioamnionitis. OBJECTIVE: This study aimed to comprehensively determine protein-coding transcriptomic differences between preterm nonlaboring and preterm laboring myometria with and without chorioamnionitis. STUDY DESIGN: Myometria were collected at cesarean delivery from preterm patients not in labor (n=16) and preterm patients in labor with chorioamnionitis (n=8) or without chorioamnionitis (n=6). Extracted RNA from myometrial tissue was prepared and sequenced using Illumina NovaSeq. Gene expression was quantified by mapping the sequence reads to the human reference genome (hg38). Differential gene expression analysis, gene set enrichment analysis, and weighted gene coexpression network analysis were used to comprehensively interrogate transcriptomic differences and their associated biology. RESULTS: Differential gene expression analysis comparing preterm patients in labor with chorioamnionitis with preterm patients not in labor identified 931 differentially expressed genes, whereas comparing preterm patients in labor without chorioamnionitis with preterm patients not in labor identified no statistically significant gene expression changes. In contrast, gene set enrichment analysis and weighted gene coexpression network analysis demonstrated that preterm labor with and without chorioamnionitis was associated with enrichment of pathways involved in activation of the innate immune system and inflammation, and activation of G protein-coupled receptors. Key genes identified included chemotactic CYP4F3, CXCL8, DOCK2, and IRF1 in preterm labor with chorioamnionitis and CYP4F3, FCAR, CHUK, and IL13RA2 in preterm labor without chorioamnionitis. There was marked overlap in the pathways enriched in both preterm labor subtypes. CONCLUSION: Differential gene expression analysis demonstrated that myometria from preterm patients in labor without chorioamnionitis and preterm patients not in labor were transcriptionally similar, whereas the presence of chorioamnionitis was associated with marked gene changes. In contrast, comprehensive bioinformatic analysis indicated that preterm labor with or without chorioamnionitis was associated with innate immune activation. All causes of preterm labor were associated with activation of the innate immune system, but this was more marked in the presence of chorioamnionitis. These data suggest that anti-inflammatory therapy may be relevant in managing preterm labor of all etiologies.


Assuntos
Corioamnionite , Trabalho de Parto , Trabalho de Parto Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Miométrio/metabolismo , Corioamnionite/genética , Corioamnionite/metabolismo , Transcriptoma , Trabalho de Parto Prematuro/genética , Trabalho de Parto Prematuro/metabolismo , Trabalho de Parto/genética , Trabalho de Parto/metabolismo , Inflamação/genética , Inflamação/metabolismo , Perfilação da Expressão Gênica
16.
Toxicol Pathol ; 51(1-2): 15-26, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078689

RESUMO

Activating mutations of the leucine-rich repeat kinase 2 (LRRK2) gene are associated with Parkinson disease (PD), prompting development of LRRK2 inhibitors as potential treatment for PD. However, kidney safety concerns have surfaced from LRRK2 knockout (KO) mice and rats and from repeat-dose studies in rodents administered LRRK2 inhibitors. To support drug development of this therapeutic target, we conducted a study of 26 weeks' duration in 2-month-old wild-type and LRRK2 KO Long-Evans Hooded rats to systematically examine the performance of urinary safety biomarkers and to characterize the nature of the morphological changes in the kidneys by light microscopy and by ultrastructural evaluation. Our data reveal the time course of early-onset albuminuria at 3 and 4 months in LRRK2 KO female and male rats, respectively. The increases in urine albumin were not accompanied by concurrent increases in serum creatinine, blood urea nitrogen, or renal safety biomarkers such as kidney injury molecule 1 or clusterin, although morphological alterations in both glomerular and tubular structure were identified by light and transmission electron microscopy at 8 months of age. Diet optimization with controlled food intake attenuated the progression of albuminuria and associated renal changes.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Proteínas Serina-Treonina Quinases , Animais , Feminino , Masculino , Camundongos , Ratos , Albuminúria/patologia , Biomarcadores , Rim/patologia , Leucina , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Camundongos Knockout , Mutação , Doença de Parkinson/tratamento farmacológico , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ratos Long-Evans
17.
Nature ; 544(7651): 484-487, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-28405026

RESUMO

The relationship between dinosaurs and other reptiles is well established, but the sequence of acquisition of dinosaurian features has been obscured by the scarcity of fossils with transitional morphologies. The closest extinct relatives of dinosaurs either have highly derived morphologies or are known from poorly preserved or incomplete material. Here we describe one of the stratigraphically lowest and phylogenetically earliest members of the avian stem lineage (Avemetatarsalia), Teleocrater rhadinus gen. et sp. nov., from the Middle Triassic epoch. The anatomy of T. rhadinus provides key information that unites several enigmatic taxa from across Pangaea into a previously unrecognized clade, Aphanosauria. This clade is the sister taxon of Ornithodira (pterosaurs and birds) and shortens the ghost lineage inferred at the base of Avemetatarsalia. We demonstrate that several anatomical features long thought to characterize Dinosauria and dinosauriforms evolved much earlier, soon after the bird-crocodylian split, and that the earliest avemetatarsalians retained the crocodylian-like ankle morphology and hindlimb proportions of stem archosaurs and early pseudosuchians. Early avemetatarsalians were substantially more species-rich, widely geographically distributed and morphologically diverse than previously recognized. Moreover, several early dinosauromorphs that were previously used as models to understand dinosaur origins may represent specialized forms rather than the ancestral avemetatarsalian morphology.


Assuntos
Aves/classificação , Dinossauros/anatomia & histologia , Dinossauros/classificação , Fósseis , Filogenia , Jacarés e Crocodilos/anatomia & histologia , Jacarés e Crocodilos/classificação , Animais , Aves/anatomia & histologia , Membro Posterior/anatomia & histologia , Esqueleto/anatomia & histologia , Tanzânia
18.
Am J Perinatol ; 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37579763

RESUMO

OBJECTIVE: We used patients' medical and psychosocial risk factors to explore prenatal care utilization and health outcomes to inform prenatal care tailoring. STUDY DESIGN: This retrospective cohort study assessed patients who gave birth at an academic institution from January 1 to December 31, 2018, using electronic health record (EHR) data. Patients were categorized into four phenotypes based on medical/psychosocial risk factors available in the EHR: Completely low risk; High psychosocial risk only; High medical risk only; and Completely high risk. We examined patient characteristics, visit utilization, nonvisit utilization (e.g., phone calls), and outcomes (e.g., preterm birth, preeclampsia) across groups. RESULTS: Of 4,681 patients, the majority were age 18 to 35 (3,697, 79.0%), White (3,326, 70.9%), multiparous (3,263, 69.7%), and Completely high risk (2,752, 58.8%). More Black and Hispanic patients had psychosocial risk factors than White patients. Patients with psychosocial risk factors had fewer prenatal visits (10, interquartile range [IQR]: 8-12) than those without (11, IQR: 9-12). Patients with psychosocial risk factors experienced less time in prenatal care, more phone calls, and fewer EHR messages across the same medical risk group. Rates of preterm birth and gestational hypertension were incrementally higher with additional medical/psychosocial risk factors. CONCLUSION: Data readily available in the EHR can assess the compounding influence of medical/psychosocial risk factor on patients' care utilization and outcomes. KEY POINTS: · Medical and psychosocial needs in pregnancy can inform patient phenotypes and are associated with prenatal care use and outcomes.. · Patient phenotypes are associated with prenatal care use and outcomes.. · Patients with high psychosocial risk spent less time in prenatal care and had more phone calls in pregnancy.. · Tailored prenatal care models may proactively address differences in patient's needs..

19.
Vet Dermatol ; 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37185892

RESUMO

BACKGROUND: Oral and parenteral drug delivery in horses can be difficult. Equine-specific transdermal drug formulations offer improved ease of treatment; development of such formulations requires a deeper understanding of the structural and chemical tissue barrier of horse skin. HYPOTHESIS/OBJECTIVES: To compare the structural composition and barrier properties of equine skin. ANIMALS: Six warmblood horses (two males, four females) with no skin diseases. MATERIALS AND METHODS: Routine histological and microscopic analyses were carried out with image analysis for skin from six different anatomical locations. In vitro drug permeation was analysed using a standard Franz diffusion cell protocol coupled with reversed phase-high-performance liquid chromatography detailing flux, lag times and tissue partitioning ratios of two model drug compounds. RESULTS: Epidermal and dermal thicknesses varied between sites. The dermal and epidermal thicknesses of the croup were 1764 ± 115 µm and 36 ± 3.6 µm, respectively, and were significantly different (p < 0.05) from the inner thigh thicknesses which were 824 ± 35 µm and 49 ± 3.6 µm. Follicular density and size also varied. The highest flux for the model hydrophilic molecule (caffeine) was for the flank (3.22 ± 0.36 µg/cm2 /h), while that for the lipophilic molecule (ibuprofen) was for the inner thigh (0.12 ± 0.02 µg/cm2 /h). CONCLUSIONS AND CLINICAL RELEVANCE: Anatomical location differences in equine skin structure and small molecule permeability were demonstrated. These results can aid in the development of transdermal therapies for horses.

20.
J Equine Sci ; 34(3): 67-72, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37781569

RESUMO

Resveratrol (RSV; trans-3,5,4'-trihydroxystilbene) strongly activates sirtuin 1, and it and its analogue V29 enhance the proliferation of mesenchymal stem/stromal cells (MSCs).Although culture medium containing 5-azacytydine and RSV inhibits senescence of adipose tissue-derived MSCs isolated from horses with metabolic syndrome, few studies have reported the effects of RSV on equine bone marrow-derived MSCs (eBMMSCs) isolated from horses without metabolic syndrome. The aim of this study was to investigate the effects of RSV and V29 on the cell cycle of eBMMSCs. Following treatment with 5 µM RSV or 10 µM V29, the cell proliferation capacity of eBMMSCs derived from seven horses was evaluated by EdU (5-ethynyl-2'-deoxyuridine) and Ki-67 antibody assays. Brightfield images of cells and immunofluorescent images of EdU, Ki-67, and DAPI staining were recorded by fluorescence microscopy, and the number of cells positive for each was quantified and compared by Friedman's test at P<0.05. The growth fraction of eBMMSCs was significantly increased by RSV and V29 as measured by the EdU assay (control 28.1% ± 13.8%, V29 31.8% ± 14.6%, RSV 32.0% ± 10.8%; mean ± SD; P<0.05) but not as measured by the Ki-67 antibody assay (control 27.0% ± 11.2%, V29 27.4% ± 10.8%, RSV 27.7% ± 6.8%). RSV and V29 promoted progression of the cell cycle of eBMMSCs into the S phase and may be useful for eBMMSC expansion.

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