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1.
Cell ; 183(4): 890-904.e29, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-33157037

RESUMEN

The Eastern Eurasian Steppe was home to historic empires of nomadic pastoralists, including the Xiongnu and the Mongols. However, little is known about the region's population history. Here, we reveal its dynamic genetic history by analyzing new genome-wide data for 214 ancient individuals spanning 6,000 years. We identify a pastoralist expansion into Mongolia ca. 3000 BCE, and by the Late Bronze Age, Mongolian populations were biogeographically structured into three distinct groups, all practicing dairy pastoralism regardless of ancestry. The Xiongnu emerged from the mixing of these populations and those from surrounding regions. By comparison, the Mongols exhibit much higher eastern Eurasian ancestry, resembling present-day Mongolic-speaking populations. Our results illuminate the complex interplay between genetic, sociopolitical, and cultural changes on the Eastern Steppe.


Asunto(s)
Genética de Población , Pradera , Arqueología , Europa (Continente) , Femenino , Frecuencia de los Genes/genética , Pool de Genes , Heterogeneidad Genética , Genoma Humano , Geografía , Haplotipos/genética , Historia Antigua , Humanos , Masculino , Mongolia , Análisis de Componente Principal , Factores de Tiempo
2.
Nature ; 598(7882): 629-633, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34526723

RESUMEN

During the Early Bronze Age, populations of the western Eurasian steppe expanded across an immense area of northern Eurasia. Combined archaeological and genetic evidence supports widespread Early Bronze Age population movements out of the Pontic-Caspian steppe that resulted in gene flow across vast distances, linking populations of Yamnaya pastoralists in Scandinavia with pastoral populations (known as the Afanasievo) far to the east in the Altai Mountains1,2 and Mongolia3. Although some models hold that this expansion was the outcome of a newly mobile pastoral economy characterized by horse traction, bulk wagon transport4-6 and regular dietary dependence on meat and milk5, hard evidence for these economic features has not been found. Here we draw on proteomic analysis of dental calculus from individuals from the western Eurasian steppe to demonstrate a major transition in dairying at the start of the Bronze Age. The rapid onset of ubiquitous dairying at a point in time when steppe populations are known to have begun dispersing offers critical insight into a key catalyst of steppe mobility. The identification of horse milk proteins also indicates horse domestication by the Early Bronze Age, which provides support for its role in steppe dispersals. Our results point to a potential epicentre for horse domestication in the Pontic-Caspian steppe by the third millennium BC, and offer strong support for the notion that the novel exploitation of secondary animal products was a key driver of the expansions of Eurasian steppe pastoralists by the Early Bronze Age.


Asunto(s)
Industria Lechera/historia , Migración Humana , Proteoma , Animales , Arqueología , Asia , Cálculos Dentales/metabolismo , Domesticación , Europa (Continente) , Flujo Génico , Pradera , Historia Antigua , Caballos , Humanos , Leche
3.
Proc Natl Acad Sci U S A ; 120(45): e2301534120, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37903257

RESUMEN

L-type voltage-gated calcium (Ca2+) channels (L-VGCC) dysfunction is implicated in several neurological and psychiatric diseases. While a popular therapeutic target, it is unknown whether molecular mechanisms leading to disrupted L-VGCC across neurodegenerative disorders are conserved. Importantly, L-VGCC integrate synaptic signals to facilitate a plethora of cellular mechanisms; however, mechanisms that regulate L-VGCC channel density and subcellular compartmentalization are understudied. Herein, we report that in disease models with overactive mammalian target of rapamycin complex 1 (mTORC1) signaling (or mTORopathies), deficits in dendritic L-VGCC activity are associated with increased expression of the RNA-binding protein (RBP) Parkinsonism-associated deglycase (DJ-1). DJ-1 binds the mRNA coding for the alpha and auxiliary Ca2+ channel subunits CaV1.2 and α2δ2, and represses their mRNA translation, only in the disease states, specifically preclinical models of tuberous sclerosis complex (TSC) and Alzheimer's disease (AD). In agreement, DJ-1-mediated repression of CaV1.2/α2δ2 protein synthesis in dendrites is exaggerated in mouse models of AD and TSC, resulting in deficits in dendritic L-VGCC calcium activity. Finding of DJ-1-regulated L-VGCC activity in dendrites in TSC and AD provides a unique signaling pathway that can be targeted in clinical mTORopathies.


Asunto(s)
Enfermedad de Alzheimer , Esclerosis Tuberosa , Animales , Ratones , Enfermedad de Alzheimer/genética , Calcio/metabolismo , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Dendritas/metabolismo , Mamíferos/metabolismo , Esclerosis Tuberosa/genética
4.
BMC Genomics ; 25(1): 1013, 2024 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-39472826

RESUMEN

Collagenous connective tissue, found throughout the bodies of metazoans, plays a crucial role in maintaining structural integrity. This versatile tissue has the potential for numerous biomedical applications, including the development of innovative collagen-based biomaterials. Inspiration for such advancements can be drawn from echinoderms, a group of marine invertebrates that includes sea stars, sea cucumbers, brittle stars, sea urchins, and sea lilies. Through their nervous system, these organisms can reversibly control the pliability of their connective tissue components (i.e., tendons and ligaments) that are composed of mutable collagenous tissue (MCT). The variable tensile properties of the MCT allow echinoderms to perform unique functions, including postural maintenance, reduction of muscular energy use, autotomy to avoid predators, and asexual reproduction through fission. The changes in the tensile strength of MCT structures are specifically controlled by specialized neurosecretory cells called juxtaligamental cells. These cells release substances that either soften or stiffen the MCT. So far, only a few of these substances have been purified and characterized, and the genetic underpinning of MCT biology remains unknown. Therefore, we have conducted this research to identify MCT-related genes in echinoderms as a first step towards a better understanding of the MCT molecular control mechanisms. Our ultimate goal is to unlock new biomaterial applications based on this knowledge. In this project, we used RNA-Seq to identify and annotate differentially expressed genes in the MCT structures of the brittle star Ophiomastix wendtii. As a result, we present a list of 16 putative MCT modulator genes, which will be validated and characterized in forthcoming functional analyses.


Asunto(s)
Colágeno , Equinodermos , RNA-Seq , Animales , Colágeno/metabolismo , Colágeno/genética , Equinodermos/genética , Transcriptoma , Perfilación de la Expresión Génica
5.
Clin Gastroenterol Hepatol ; 22(8): 1596-1604.e4, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38513982

RESUMEN

BACKGROUND & AIMS: Endoscopic Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) detection is invasive and expensive. Nonendoscopic BE/EAC detection tools are guideline-endorsed alternatives. We previously described a 5-methylated DNA marker (MDM) panel assayed on encapsulated sponge cell collection device (CCD) specimens. We aimed to train a new algorithm using a 3-MDM panel and test its performance in an independent cohort. METHODS: Algorithm training and test samples were from 2 prospective multicenter cohorts. All BE cases had esophageal intestinal metaplasia (with or without dysplasia/EAC); control subjects had no endoscopic evidence of BE. The CCD procedure was followed by endoscopy. From CCD cell lysates, DNA was extracted, bisulfite treated, and MDMs were blindly assayed. The algorithm was set and locked using cross-validated logistic regression (training set) and its performance was assessed in an independent test set. RESULTS: Training (N = 352) and test (N = 125) set clinical characteristics were comparable. The final panel included 3 MDMs (NDRG4, VAV3, ZNF682). Overall sensitivity was 82% (95% CI, 68%-94%) at 90% (79%-98%) specificity and 88% (78%-94%) sensitivity at 84% (70%-93%) specificity in training and test sets, respectively. Sensitivity was 90% and 68% for all long- and short-segment BE, respectively. Sensitivity for BE with high-grade dysplasia and EAC was 100% in training and test sets. Overall sensitivity for nondysplastic BE was 82%. Areas under the receiver operating characteristic curves for BE detection were 0.92 and 0.94 in the training and test sets, respectively. CONCLUSIONS: A locked 3-MDM panel algorithm for BE/EAC detection using a nonendoscopic CCD demonstrated excellent sensitivity for high-risk BE cases in independent validation samples. (Clinical trials.gov: NCT02560623, NCT03060642.).


Asunto(s)
Algoritmos , Esófago de Barrett , Humanos , Esófago de Barrett/diagnóstico , Esófago de Barrett/patología , Estudios Prospectivos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Sensibilidad y Especificidad , Adulto , Metilación de ADN , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patología , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología
6.
Artículo en Inglés | MEDLINE | ID: mdl-39477082

RESUMEN

BACKGROUND AND AIMS: In previous studies methylated DNA markers (MDMs) have been identified in pancreatic juice (PJ) for detecting pancreatic ductal adenocarcinoma (PDAC). In this prospective multicenter study, the sensitivity and specificity characteristics of this panel of PJ-MDMs was evaluated standalone and in combination with plasma CA 19-9. METHODS: Paired PJ and plasma were assayed from 88 biopsy-proven treatment naïve PDAC cases and 134 controls (normal pancreas: 53, chronic pancreatitis (CP): 23, intraductal papillary mucinous neoplasm (IPMN): 58). Bisulfite-converted DNA from buffered PJ was analyzed using long-probe quantitative amplified signal assay targeting 14 MDMs (NDRG4, BMP3, TBX15, C13orf18, PRKCB, CLEC11A, CD1D, ELMO1, IGF2BP1, RYR2, ADCY1, FER1L4, EMX1, and LRRC4) and a reference gene (methylated B3GALT6). Logistic regression was used to fit the previously identified 3-MDM PJ panel (FER1L4, C13orf18 and BMP3). Discrimination accuracy was summarized using area under the receiver operating characteristic curve (AUROC) with corresponding 95% confidence intervals. RESULTS: Methylated FER1L4 had the highest individual AUROC of 0.83 (95% CI: 0.78-0.89). The AUROC for the 3-MDM PJ + Plasma CA 19-9 model (0.95 (0.92-0.98))) was higher than both the 3-MDM PJ panel (0.87 (0.82-0.92)) and plasma CA 19-9 alone ((0.91 (0.87-0.96) (p=0.0002 and 0.0135, respectively). At a specificity of 88% (95% CI: 81-93%), the sensitivity of this model was 89% (80-94%) for all PDAC stages and 83% (64-94%) for stage I/II PDAC. CONCLUSION: A panel combining PJ-MDMs and plasma CA19-9 discriminates PDAC from both healthy and disease control groups with high accuracy. This provides support for combining pancreatic juice and blood-based biomarkers for enhancing diagnostic sensitivity and successful early PDAC detection.

7.
Mol Ecol ; 33(19): e17527, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39279684

RESUMEN

The extremely rich palaeontological record of the horse family, also known as equids, has provided many examples of macroevolutionary change over the last ~55 Mya. This family is also one of the most documented at the palaeogenomic level, with hundreds of ancient genomes sequenced. While these data have advanced understanding of the domestication history of horses and donkeys, the palaeogenomic record of other equids remains limited. In this study, we have generated genome-wide data for 25 ancient equid specimens spanning over 44 Ky and spread across Anatolia, the Caucasus, Central Asia and Mongolia. Our dataset includes the genomes from two extinct species, the European wild ass, Equus hydruntinus, and the sussemione Equus ovodovi. We document, for the first time, the presence of sussemiones in Mongolia and their survival around ~3.9 Kya, a finding that should be considered when discussing the timing of the first arrival of the domestic horse in the region. We also identify strong spatial differentiation within the historical ecological range of Asian wild asses, Equus hemionus, and incomplete reproductive isolation in several groups yet considered as different species. Finally, we find common selection signatures at ANTXR2 gene in European, Asian and African wild asses. This locus, which encodes a receptor for bacterial toxins, shows no selection signal in E. ovodovi, but a 5.4-kb deletion within intron 7. Whether such genetic modifications played any role in the sussemione extinction remains unknown.


Asunto(s)
Equidae , Genética de Población , Animales , Equidae/genética , Mongolia , Genoma/genética , Filogenia , Fósiles , Caballos/genética , Adaptación Fisiológica/genética
8.
Exp Physiol ; 109(5): 754-765, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38488681

RESUMEN

This study investigates the effects of varying loading conditions on excitability in neural pathways and gait dynamics. We focussed on evaluating the magnitude of the Hoffman reflex (H-reflex), a neurophysiological measure representing the capability to activate motor neurons and the timing and placement of the foot during walking. We hypothesized that weight manipulation would alter H-reflex magnitude, footfall and lower body kinematics. Twenty healthy participants were recruited and subjected to various weight-loading conditions. The H-reflex, evoked by stimulating the tibial nerve, was assessed from the dominant leg during walking. Gait was evaluated under five conditions: body weight, 20% and 40% additional body weight, and 20% and 40% reduced body weight (via a harness). Participants walked barefoot on a treadmill under each condition, and the timing of electrical stimulation was set during the stance phase shortly after the heel strike. Results show that different weight-loading conditions significantly impact the timing and placement of the foot and gait stability. Weight reduction led to a 25% decrease in double limb support time and an 11% narrowing of step width, while weight addition resulted in an increase of 9% in step width compared to body weight condition. Furthermore, swing time variability was higher for both the extreme weight conditions, while the H-reflex reduced to about 45% between the extreme conditions. Finally, the H-reflex showed significant main effects on variability of both stance and swing phases, indicating that muscle-motor excitability might serve as feedback for enhanced regulation of gait dynamics under challenging conditions.


Asunto(s)
Marcha , Reflejo H , Caminata , Soporte de Peso , Humanos , Marcha/fisiología , Reflejo H/fisiología , Masculino , Adulto , Femenino , Soporte de Peso/fisiología , Fenómenos Biomecánicos/fisiología , Adulto Joven , Caminata/fisiología , Estimulación Eléctrica/métodos , Músculo Esquelético/fisiología , Nervio Tibial/fisiología , Electromiografía , Pie/fisiología , Adaptación Fisiológica/fisiología , Neuronas Motoras/fisiología , Peso Corporal/fisiología
9.
Cell Biochem Funct ; 42(4): e4036, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38778584

RESUMEN

Ferroptosis is a novel nonapoptotic form of cell death characterized by iron-dependent reactive oxygen species-mediated lipid peroxidation. In several different cell systems, the tumor suppressor p53 can enhance sensitivity to ferroptotic inducers. At least half of all human cancers show loss of function of p53. Furthermore, many of those tumors express mutant forms of p53 that has lost its wild-type function. Several groups have designed small molecules that can reactivate the wild-type function of these missense p53 mutants. We reasoned that p53 reactivators may also enhance sensitivity of certain cancer cells to ferroptosis stimuli. To test this idea we combined a number of different p53 reactivators with small molecule inducers of ferroptosis. In contrast, we observed that several p53 reactivators protected cells from cell death induced by ferroptotic inducers. Surprisingly, this protection still occurred in p53-null cell lines. We observed that these reactivators were neither free radical scavengers nor ion chelators. One of these p53 reactivator molecules, NSC 59984, reduced expression of GPX4, which is unlikely to explain its ability to reduce sensitivity to ferroptosis. We suggest that these p53 reactivators function via an unknown, p53-independent manner to suppress ferroptosis.


Asunto(s)
Neoplasias de la Mama , Ferroptosis , Proteína p53 Supresora de Tumor , Humanos , Ferroptosis/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/antagonistas & inhibidores , Peroxidación de Lípido/efectos de los fármacos , Mutación
10.
J Water Health ; 22(8): 1429-1443, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39212280

RESUMEN

Escherichia coli and total coliforms are important tools for identifying potential faecal contamination in drinking water. However, metagenomics offers a powerful approach for delving deeper into a bacterial community when E. coli or total coliforms are detected. Metagenomics can identify microbes native to water systems, track community changes and potential pathogens introduced by contamination events, and evaluate the effectiveness of treatment processes. Here, we demonstrate how the dual application of traditional monitoring practices and metagenomics can improve monitoring and surveillance for water resource management. The robustness of long-read metagenomics across replicates is demonstrated by the effect and interaction between manganese filters and bacterial communities, as well as the impact of chlorination after coliform detection. These examples reveal how metagenomics can identify the complex bacterial communities in the distribution system and the source waters used to supply drinking water treatment plants (DWTPs). The knowledge gained increases confidence in identified causes and mitigations of potential contamination events. By exploring bacterial communities, we can gain additional insights into the impact of faecal contamination events and treatment processes. This insight enables more precise remediation actions and enhances confidence in communicating health risks to drinking water operators and the public.


Asunto(s)
Bacterias , Agua Potable , Metagenómica , ARN Ribosómico 16S , Microbiología del Agua , Agua Potable/microbiología , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética , Metagenómica/métodos , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Purificación del Agua , Escherichia coli/aislamiento & purificación , Escherichia coli/genética , Heces/microbiología , Monitoreo del Ambiente/métodos
11.
J Biol Chem ; 298(8): 102263, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35843311

RESUMEN

Mixed lineage kinase 3 (MLK3) is a serine/threonine mitogen-activated protein kinase kinase kinase that promotes the activation of multiple mitogen-activated protein kinase pathways and is required for invasion and proliferation of ovarian cancer cells. Inhibition of MLK activity causes G2/M arrest in HeLa cells; however, the regulation of MLK3 during ovarian cancer cell cycle progression is not known. Here, we found that MLK3 is phosphorylated in mitosis and that inhibition of cyclin-dependent kinase 1 (CDK1) prevented MLK3 phosphorylation. In addition, we observed that c-Jun N-terminal kinase, a downstream target of MLK3 and a direct target of MKK4 (SEK1), was activated in G2 phase when CDK2 activity is increased and then inactivated at the beginning of mitosis concurrent with the increase in CDK1 and MLK3 phosphorylation. Using in vitro kinase assays and phosphomutants, we determined that CDK1 phosphorylates MLK3 on Ser548 and decreases MLK3 activity during mitosis, whereas CDK2 phosphorylates MLK3 on Ser770 and increases MLK3 activity during G1/S and G2 phases. We also found that MLK3 inhibition causes a reduction in cell proliferation and a cell cycle arrest in ovarian cancer cells, suggesting that MLK3 is required for ovarian cancer cell cycle progression. Taken together, our results suggest that phosphorylation of MLK3 by CDK1 and CDK2 is important for the regulation of MLK3 and c-Jun N-terminal kinase activities during G1/S, G2, and M phases in ovarian cancer cell division.


Asunto(s)
Proteína Quinasa CDC2 , Quinasa 2 Dependiente de la Ciclina , Neoplasias Ováricas , Proteína Quinasa CDC2/metabolismo , División Celular/genética , Línea Celular Tumoral , Quinasa 2 Dependiente de la Ciclina/metabolismo , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular , Células HeLa , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Mitosis , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Fosforilación , Proteina Quinasa Quinasa Quinasa 11 Activada por Mitógeno
12.
Glob Chang Biol ; 29(24): 6900-6911, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37804212

RESUMEN

The global decline of terrestrial species is largely due to the degradation, loss and fragmentation of their habitats. The conversion of natural ecosystems for cropland, rangeland, forest products and human infrastructure are the primary causes of habitat deterioration. Due to the paucity of data on the past distribution of species and the scarcity of fine-scale habitat conversion maps, however, accurate assessment of the recent effects of habitat degradation, loss and fragmentation on the range of mammals has been near impossible. We aim to assess the proportions of available habitat within the lost and retained parts of mammals' distribution ranges, and to identify the drivers of habitat availability. We produced distribution maps for 475 terrestrial mammals for the range they occupied 50 years ago and compared them to current range maps. We then calculated the differences in the percentage of 'area of habitat' (habitat available to a species within its range) between the lost and retained range areas. Finally, we ran generalized linear mixed models to identify which variables were more influential in determining habitat availability in the lost and retained parts of the distribution ranges. We found that 59% of species had a lower proportion of available habitat in the lost range compared to the retained range, thus hypothesizing that habitat loss could have contributed to range declines. The most important factors negatively affecting habitat availability were the conversion of land to rangeland and high density of livestock. Significant intrinsic traits were those related to reproductive timing and output, habitat breadth and medium body size. Our findings emphasize the importance of implementing conservation strategies to mitigate the impacts caused by human activities on the habitats of mammals, and offer evidence indicating which species have the potential to reoccupy portions of their former range if other threats cease to occur.


Asunto(s)
Ecosistema , Ganado , Animales , Humanos , Conservación de los Recursos Naturales , Mamíferos , Bosques
13.
Gynecol Oncol ; 174: 11-20, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37141817

RESUMEN

OBJECTIVE: Alterations in DNA methylation are early events in endometrial cancer (EC) development and may have utility in EC detection via tampon-collected vaginal fluid. METHODS: For discovery, DNA from frozen EC, benign endometrium (BE), and benign cervicovaginal (BCV) tissues underwent reduced representation bisulfite sequencing (RRBS) to identify differentially methylated regions (DMRs). Candidate DMRs were selected based on receiver operating characteristic (ROC) discrimination, methylation level fold-change between cancers and controls, and absence of background CpG methylation. Methylated DNA marker (MDM) validation was performed using qMSP on DNA from independent EC and BE FFPE tissue sets. Women ≥45 years of age with abnormal uterine bleeding (AUB) or postmenopausal bleeding (PMB) or any age with biopsy-proven EC self-collected vaginal fluid using a tampon prior to clinically indicated endometrial sampling or hysterectomy. Vaginal fluid DNA was assayed by qMSP for EC-associated MDMs. Random forest modeling analysis was performed to generate predictive probability of underlying disease; results were 500-fold in-silico cross-validated. RESULTS: Thirty-three candidate MDMs met performance criteria in tissue. For the tampon pilot, 100 EC cases were frequency matched by menopausal status and tampon collection date to 92 BE controls. A 28-MDM panel highly discriminated between EC and BE (96% (95%CI 89-99%) specificity; 76% (66-84%) sensitivity (AUC 0.88). In PBS/EDTA tampon buffer, the panel yielded 96% (95% CI 87-99%) specificity and 82% (70-91%) sensitivity (AUC 0.91). CONCLUSION: Next generation methylome sequencing, stringent filtering criteria, and independent validation yielded excellent candidate MDMs for EC. EC-associated MDMs performed with promisingly high sensitivity and specificity in tampon-collected vaginal fluid; PBS-based tampon buffer with added EDTA improved sensitivity. Larger tampon-based EC MDM testing studies are warranted.


Asunto(s)
Neoplasias Endometriales , Humanos , Femenino , Marcadores Genéticos , Ácido Edético/metabolismo , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/genética , Neoplasias Endometriales/metabolismo , Endometrio/metabolismo , ADN , Metilación de ADN
14.
Exp Cell Res ; 413(2): 113063, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35167828

RESUMEN

C9ORF78 is a poorly characterized protein found in diverse eukaryotes. Previous work indicated overexpression of C9ORF78 in malignant tissues indicating a possible involvement in growth regulatory pathways. Additional studies in fission yeast and humans uncover a potential function in regulating the spliceosome. In studies of GFP-tagged C9ORF78 we observed a dramatic reduction in protein abundance in cells grown to confluence and/or deprived of serum growth factors. Serum stimulation induced synchronous re-expression of the protein in HeLa cells. This effect was also observed with the endogenous protein. Overexpressing either E2F1 or N-Myc resulted in elevated C9ORF78 expression potentially explaining the serum-dependent upregulation of the protein. Immunofluorescence analysis indicates that C9ORF78 localizes to nuclei in interphase but does not appear to concentrate in speckles as would be expected for a splicing protein. Surprisingly, a subpopulation of C9ORF78 co-localizes with ACA, Mad1 and Ndc80 in mitotic cells suggesting that this protein associates with kinetochores or centromeres. Levels of C9ORF78 at the centromere/kinetochore also increased upon activation of the mitotic checkpoint. Furthermore, knocking-down C9ORF78 caused mitotic defects. These studies uncover novel mitotic function and subcellular localization of C9ORF78.


Asunto(s)
Centrómero , Segregación Cromosómica , Cinetocoros , Humanos , Centrómero/genética , Centrómero/metabolismo , Segregación Cromosómica/genética , Células HeLa , Cinetocoros/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Mitosis/genética
15.
Proc Natl Acad Sci U S A ; 117(47): 29569-29576, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33139545

RESUMEN

Horseback riding was a transformative force in the ancient world, prompting radical shifts in human mobility, warfare, trade, and interaction. In China, domestic horses laid the foundation for trade, communication, and state infrastructure along the ancient Silk Road, while also stimulating key military, social, and political changes in Chinese society. Nonetheless, the emergence and adoption of mounted horseback riding in China is still poorly understood, particularly due to a lack of direct archaeological data. Here we present a detailed osteological study of eight horse skeletons dated to ca. 350 BCE from the sites of Shirenzigou and Xigou in Xinjiang, northwest China, prior to the formalization of Silk Road trade across this key region. Our analyses reveal characteristic osteological changes associated with equestrian practices on all specimens. Alongside other relevant archaeological evidence, these data provide direct evidence for mounted horseback riding, horse equipment, and mounted archery in northwest China by the late first millennium BCE. Most importantly, our results suggest that this region may have played a crucial role in the spread of equestrian technologies from the Eurasian interior to the settled civilizations of early China, where horses facilitated the rise of the first united Chinese empires and the emergence of transcontinental trade networks.


Asunto(s)
Caballos/fisiología , Deportes/fisiología , Animales , Arqueología/métodos , China , Esqueleto/fisiología
16.
Neurosurg Focus ; 54(1): E3, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36587405

RESUMEN

OBJECTIVE: The aim of this paper was to evaluate the changes in radiographic spinopelvic parameters in a large cohort of patients undergoing the prone transpsoas approach to the lumbar spine. METHODS: A multicenter retrospective observational cohort study was performed for all patients who underwent lateral lumber interbody fusion via the single-position prone transpsoas (PTP) approach. Spinopelvic parameters from preoperative and first upright postoperative radiographs were collected, including lumbar lordosis (LL), pelvic incidence (PI), and pelvic tilt (PT). Functional indices (visual analog scale score), and patient-reported outcomes (Oswestry Disability Index) were also recorded from pre- and postoperative appointments. RESULTS: Of the 363 patients who successfully underwent the procedure, LL after fusion was 50.0° compared with 45.6° preoperatively (p < 0.001). The pelvic incidence-lumbar lordosis mismatch (PI-LL) was 10.5° preoperatively versus 2.9° postoperatively (p < 0.001). PT did not significantly change (0.2° ± 10.7°, p > 0.05). CONCLUSIONS: The PTP approach allows significant gain in lordotic augmentation, which was associated with good functional results at follow-up.


Asunto(s)
Lordosis , Fusión Vertebral , Humanos , Estudios Retrospectivos , Lordosis/diagnóstico por imagen , Lordosis/cirugía , Complicaciones Posoperatorias/epidemiología , Fusión Vertebral/métodos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Resultado del Tratamiento
17.
J Neuroeng Rehabil ; 20(1): 145, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37884944

RESUMEN

BACKGROUND: Manual wheelchair propulsion is widely accepted to be biomechanically inefficient, with a high prevalence of shoulder pain and injuries among users. Directional control during wheelchair movement is a major, yet largely overlooked source of energy loss: changing direction or maintaining straightforward motion on tilted surfaces requires unilateral braking. This study evaluates the efficiency of a novel steering-by-leaning mechanism that guides wheelchair turning through upper body leaning. METHODS: 16 full-time wheelchair users and 15 able-bodied novices each completed 12 circuits of an adapted Illinois Agility Test-course that included tilted, straight, slalom, and 180° turning sections in a prototype wheelchair at a self-selected functional speed. Trials were alternated between conventional and steering-by-leaning modes while propulsion forces were recorded via instrumented wheelchair wheels. Time to completion, travelled distance, positive/negative power, and work done, were all calculated to allow comparison of the control modes using repeated measures analysis of variance. RESULTS: Substantial average energy reductions of 51% (able-bodied group) and 35% (wheelchair user group) to complete the task were observed when using the steering-by-leaning system. Simultaneously, able-bodied subjects were approximately 23% faster whereby completion times did not differ for wheelchair users. Participants in both groups wheeled some 10% further with the novel system. Differences were most pronounced during turning and on tilted surfaces where the steering-by-leaning system removed the need for braking for directional control. CONCLUSIONS: Backrest-actuated steering systems on manual wheelchairs can make a meaningful contribution towards reducing shoulder usage while contributing to independent living. Optimisation of propulsion techniques could further improve functional outcomes.


Asunto(s)
Hombro , Silla de Ruedas , Humanos , Fenómenos Biomecánicos , Extremidad Superior , Dolor de Hombro
18.
Sensors (Basel) ; 23(18)2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37765865

RESUMEN

Adolescent idiopathic scoliosis (AIS) is a prevalent musculoskeletal disorder that causes abnormal spinal deformities. The early screening of children and adolescents is crucial to identify and prevent the further progression of AIS. In clinical examinations, scoliometers are often used to noninvasively estimate the primary Cobb angle, and optical 3D scanning systems have also emerged as alternative noninvasive approaches for this purpose. The recent advances in low-cost 3D scanners have led to their use in several studies to estimate the primary Cobb angle or even internal spinal alignment. However, none of these studies demonstrate whether such a low-cost scanner satisfies the minimal requirements for capturing the relevant deformities of the human back. To practically quantify the minimal required spatial resolution and camera resolution to capture the geometry and shape of the deformities of the human back, we used multiple 3D scanning methodologies and systems. The results from an evaluation of 30 captures of AIS patients and 76 captures of healthy subjects showed that the minimal required spatial resolution is between 2 mm and 5 mm, depending on the chosen error tolerance. Therefore, a minimal camera resolution of 640 × 480 pixels is recommended for use in future studies.


Asunto(s)
Enfermedades Musculoesqueléticas , Dispositivos Ópticos , Adolescente , Niño , Humanos , Voluntarios Sanos
19.
J Stroke Cerebrovasc Dis ; 32(5): 107059, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36842351

RESUMEN

OBJECTIVES: The COVID-19 pandemic has heightened awareness of health disparities associated with socioeconomic status (SES) across the United States. We examined whether household income is associated with functional outcomes after stroke and COVID-19. MATERIALS AND METHODS: This was a multi-institutional, retrospective cohort study of consecutively hospitalized patients with SARS-CoV-2 and radiographically confirmed stroke presenting from March through November 2020 to any of five comprehensive stroke centers in metropolitan Chicago, Illinois, USA. Zip-code-derived household income was dichotomized at the Chicago median. Logistic regression was used to examine the relationship between household income and good functional outcome (modified Rankin Scale 0-3 at discharge, after ischemic stroke). RESULTS: Across five hospitals, 159 patients were included. Black patients comprised 48.1%, White patients 38.6%, and Hispanic patients 27.7%. Median household income was $46,938 [IQR: $32,460-63,219]. Ischemic stroke occurred in 115 (72.3%) patients (median NIHSS 7, IQR: 0.5-18.5) and hemorrhagic stroke in 37 (23.7%). When controlling for age, sex, severe COVID-19, and NIHSS, patients with ischemic stroke and household income above the Chicago median were more likely to have a good functional outcome at discharge (OR 7.53, 95% CI 1.61 - 45.73; P=0.016). Race/ethnicity were not included in final adjusted models given collinearity with income. CONCLUSIONS: In this multi-institutional study of hospitalized patients with stroke, those residing in higher SES zip codes were more likely to have better functional outcomes, despite controlling for stroke severity and COVID-19 severity. This suggests that area-based SES factors may play a role in outcomes from stroke and COVID-19.


Asunto(s)
COVID-19 , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Estados Unidos/epidemiología , COVID-19/terapia , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/terapia , Estudios Retrospectivos , Pandemias , SARS-CoV-2 , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/terapia , Renta
20.
J Biol Chem ; 297(6): 101365, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34728216

RESUMEN

p53 is a well-established critical cell cycle regulator. By inducing transcription of the gene encoding p21, p53 inhibits cyclin-dependent kinase (CDK)-mediated phosphorylation of cell cycle inhibitor retinoblastoma (RB) proteins. Phosphorylation of RB releases E2F transcription factor proteins that transactivate cell cycle-promoting genes. Here, we sought to uncover the contribution of p53, p21, CDK, RB, and E2F to the regulation of ferroptosis, an oxidative form of cell death. Our studies have uncovered unexpected complexity in this regulation. First, we showed that elevated levels of p53 enhance ferroptosis in multiple inducible and isogenic systems. On the other hand, we found that p21 suppresses ferroptosis. Elevation of CDK activity also suppressed ferroptosis under conditions where p21 suppressed ferroptosis, suggesting that the impact of p21 must extend beyond CDK inhibition. Furthermore, we showed that overexpression of E2F suppresses ferroptosis in part via a p21-dependent mechanism, consistent with reports that this transcription factor can induce transcription of p21. Finally, deletion of RB genes enhanced ferroptosis. Taken together, these results show that signals affecting ferroptotic sensitivity emanate from multiple points within the p53 tumor suppressor pathway.


Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Factor de Transcripción E2F1/metabolismo , Ferroptosis/fisiología , Proteína de Retinoblastoma/metabolismo , Proteína p53 Supresora de Tumor/fisiología , Animales , Línea Celular Tumoral , Células Cultivadas , Humanos , Ratones , Ratones Noqueados , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
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