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1.
Anal Biochem ; 656: 114876, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36058293

RESUMEN

Paired box protein Pax-6 (oculothrombin) is a transcription factor that plays an important regulatory role in ocular, brain, and pancreatic development. Mutations of the PAX6 gene cause aniridia and Peters anomaly. Reduction in Pax-6 protein is also associated with ocular diseases such as dry eye. An electrochemiluminescence immunoassay method using the Meso Scale Discovery platform was developed to measure Pax-6 protein levels in corneal epithelial cells obtained by impression cytology. Impression cytology involves harvesting ocular epithelial cells by applying a polyethersulfone membrane patch briefly to the ocular surface using a commercially available EYEPRIM™ device. The epithelial cells that adhere to the membrane patch of the EYEPRIM™ device provide a biological sample which can be assayed for Pax-6 protein levels. Assay development identified an antibody pair capable of detecting purified recombinant Pax-6 protein produced in mammalian cells. The optimized assay has a dynamic range of 24 pg mL-1 to 100,000 pg mL-1 and a lower limit of quantification of 24 pg mL-1. Assay selectivity was demonstrated using either HeLa or HEK293 cells transfected with inhibitory RNA. Finally, the method was validated by measuring Pax-6 protein levels in impression cytology acquired samples obtained using the EYEPRIM™ device from rabbit cornea.


Asunto(s)
Proteínas de Homeodominio , Factores de Transcripción Paired Box , Animales , Proteínas del Ojo/genética , Células HEK293 , Proteínas de Homeodominio/genética , Humanos , Inmunoensayo , Mamíferos/genética , Mamíferos/metabolismo , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/genética , ARN , Conejos , Proteínas Represoras/genética
2.
Immunity ; 55(6): 998-1012.e8, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35447092

RESUMEN

SARS-CoV-2 infection or vaccination produces neutralizing antibody responses that contribute to better clinical outcomes. The receptor-binding domain (RBD) and the N-terminal domain (NTD) of the spike trimer (S) constitute the two major neutralizing targets for antibodies. Here, we use NTD-specific probes to capture anti-NTD memory B cells in a longitudinal cohort of infected individuals, some of whom were vaccinated. We found 6 complementation groups of neutralizing antibodies. 58% targeted epitopes outside the NTD supersite, 58% neutralized either Gamma or Omicron, and 14% were broad neutralizers that also neutralized Omicron. Structural characterization revealed that broadly active antibodies targeted three epitopes outside the NTD supersite including a class that recognized both the NTD and SD2 domain. Rapid recruitment of memory B cells producing these antibodies into the plasma cell compartment upon re-infection likely contributes to the relatively benign course of subsequent infections with SARS-CoV-2 variants, including Omicron.


Asunto(s)
COVID-19 , Glicoproteína de la Espiga del Coronavirus , Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Epítopos , Humanos , Células B de Memoria , SARS-CoV-2
3.
Clin Neuropsychol ; 36(2): 388-413, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35166174

RESUMEN

OBJECTIVE: Black Americans are at high risk for HIV disease and associated morbidity. The impact and clinical correlates of HIV-associated neurocognitive impairment among Black Americans is not fully understood. The current study uses a full factorial design to examine the independent and combined effects of race and HIV disease on neurocognitive functioning, including its associations with everyday functioning and clinical disease markers in Black and White persons with HIV (PWH). METHOD: Participants included 40 Black PWH, 83 White PWH, 28 Black HIV- and 64 White HIV- individuals. Neurocognition was measured by raw sample-based z-scores from a clinical battery. Everyday functioning was assessed using self- and clinician-rated measures of cognitive symptoms and activities of daily living. HIV-associated neurocognitive disorders were also classified using demographically adjusted normative standards and the Frascati criteria. RESULTS: We observed a significant three-way interaction between HIV, race, and domain on raw neurocognitive z-scores. This omnibus effect was driven by medium and large effect size decrements in processing speed and semantic memory, respectively, in Black PWH compared to other study groups. Black PWH also demonstrated higher frequencies of HIV-associated neurocognitive disorders as compared to White PWH. Unexpectedly, global neurocognitive performance was negatively related to everyday functioning impairments for White PWH, but not for Black PWH. CONCLUSIONS: Systemic disadvantages for Black Americans may combine with HIV disease to compound some neurocognitive impairments in this under-served population. Prospective studies are needed to identify better ways to prevent, measure, diagnose, and manage HIV-associated neurocognitive disorders among Black Americans.


Asunto(s)
Actividades Cotidianas , Infecciones por VIH , Actividades Cotidianas/psicología , Cognición , Infecciones por VIH/psicología , Humanos , Trastornos Neurocognitivos/etiología , Pruebas Neuropsicológicas
4.
bioRxiv ; 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35132412

RESUMEN

SARS-CoV-2 infection or vaccination produces neutralizing antibody responses that contribute to better clinical outcomes. The receptor binding domain (RBD) and the N-terminal domain (NTD) of the spike trimer (S) constitute the two major neutralizing targets for the antibody system. Neutralizing antibodies targeting the RBD bind to several different sites on this domain. In contrast, most neutralizing antibodies to NTD characterized to date bind to a single supersite, however these antibodies were obtained by methods that were not NTD specific. Here we use NTD specific probes to focus on anti-NTD memory B cells in a cohort of pre-omicron infected individuals some of which were also vaccinated. Of 275 NTD binding antibodies tested 103 neutralized at least one of three tested strains: Wuhan-Hu-1, Gamma, or PMS20, a synthetic variant which is extensively mutated in the NTD supersite. Among the 43 neutralizing antibodies that were further characterized, we found 6 complementation groups based on competition binding experiments. 58% targeted epitopes outside the NTD supersite, and 58% neutralized either Gamma or Omicron, but only 14% were broad neutralizers. Three of the broad neutralizers were characterized structurally. C1520 and C1791 recognize epitopes on opposite faces of the NTD with a distinct binding pose relative to previously described antibodies allowing for greater potency and cross-reactivity with 7 different variants including Beta, Delta, Gamma and Omicron. Antibody C1717 represents a previously uncharacterized class of NTD-directed antibodies that recognizes the viral membrane proximal side of the NTD and SD2 domain, leading to cross-neutralization of Beta, Gamma and Omicron. We conclude SARS-CoV-2 infection and/or Wuhan-Hu-1 mRNA vaccination produces a diverse collection of memory B cells that produce anti-NTD antibodies some of which can neutralize variants of concern. Rapid recruitment of these cells into the antibody secreting plasma cell compartment upon re-infection likely contributes to the relatively benign course of subsequent infections with SARS-CoV-2 variants including omicron.

5.
J Sport Rehabil ; 31(2): 253-261, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34438362

RESUMEN

CONTEXT: The Dynavision D2™ Mode A test (ModeA) is a 1-minute reaction time (RT) test commonly used in sports science research and clinical rehabilitation. However, there is limited data regarding the effect of repeated testing (ie, training) or subsequent periods of no testing (ie, detraining) on test-retest reliability and RT performance. Therefore, the purpose of this study was to examine the test-retest reliability, training, and detraining effects associated with the D2™ ModeA test. DESIGN: Repeated measures/reliability. METHODS: Twenty-four recreationally active men and women completed 15 training sessions consisting of 2 ModeA tests per session (30 tests). The participants were then randomized to either 1 or 2 weeks of detraining prior to completing 15 retraining sessions (30 tests). The training and retraining periods were separated into 10 blocks for analysis (3 tests per block). The number of hits (hits) and the average RT per hit (AvgRT) within each block were used to determine RT performance. Intraclass correlation coefficients, SEM, and minimum difference were used to determine reliability. Repeated-measures analysis of variance/analysis of covariance were used to determine training and detraining effects, respectively. RESULTS: The ModeA variables demonstrated excellent test-retest reliability (intraclass correlation coefficient2,3 > .93). Significant improvements in hits and AvgRT were noted within training blocks 1 to 5 (P < .05). No further improvements in RT performance were noted between training blocks 6 through 10. There was no effect of detraining period on RT. The RT performance was not different between blocks during retraining. CONCLUSIONS: It appears that 15 tests are necessary to overcome the training effect and establish reliable baseline performance for the ModeA test. Detraining for 1 to 2 weeks did not impact RT performance. The authors recommend that investigators and clinicians utilize the average of 3 tests when assessing RT performance using the D2 ModeA test.


Asunto(s)
Tiempo de Reacción , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
6.
Clin Neuropsychol ; 36(6): 1226-1243, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33164675

RESUMEN

Objective: Women are becoming more prevalent in clinical neuropsychology, but gender bias and disparities persist across multiple professional domains. This study examined potential gender disparities in historical authorship trends across commonly read journals in clinical neuropsychology. Method: Analyses were conducted on 10,531 articles published in six clinical neuropsychology journals from 1985 to 2019. Each author was coded as either a man or a woman using the OpenGenderTracking Project database. Results: On average, women comprised 43.3% (±30.6) of the authors listed in clinical neuropsychology article bylines and were lead and/or corresponding author on 50.3% of these papers. Findings varied by journal, with Child Neuropsychology having the best representation of women across several study metrics. Women comprised an increasing proportion of authors over time and the gender gap in clinical neuropsychology is smaller than was recently reported for the broader field of psychology; nevertheless, the recent rates of women as authors lag behind the prevalence of women in clinical neuropsychology. Encouragingly, gender was not associated with the number of times an article was cited. Articles that included women in leadership roles had significantly more authors overall and specifically more women authors. Conclusions: Women are under-represented as authors in clinical neuropsychology journals, but they are becoming more common and their papers are cited just as frequently as men. Efforts to increase women as research mentors and sponsors may help to further close the publishing gender gap in clinical neuropsychology.


Asunto(s)
Publicaciones Periódicas como Asunto , Edición , Niño , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Neuropsicología , Sexismo
7.
Neuropsychology ; 35(5): 461-471, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34292009

RESUMEN

Objective: While HIV disease is associated with impairment in declarative memory, the ability of people with HIV (PWH) to describe past and future autobiographical events is not known. Method: Participants included 63 PWH and 28 seronegative individuals ages 50-78 who completed standardized neurocognitive and everyday functioning assessments. Participants described four events from the recent past and four imagined events in the near future, details from which were classified as internal or external to the main event. Result: PWH produced fewer autobiographical details with small-to-medium effect sizes but did not differ from seronegative participants in meta-cognitive ratings of their performance. Performance of the study groups did not vary across past or future probes or internal versus external details; however, within the entire sample, past events were described in greater detail than future events, and more external than internal details were produced. Within the PWH group, the production of fewer internal details for future events was moderately associated with poorer prospective memory, executive dysfunction, and errors on a laboratory-based task of medication management. Conclusion: Older PWH may experience difficulty generating autobiographical details from the past and simulated events in the future, which may be related to executive dyscontrol of memory processes. Future studies might examine the role of future thinking in health behaviors such as medication adherence and retention in healthcare among PWH. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Disfunción Cognitiva , Infecciones por VIH , Memoria Episódica , Anciano , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Imaginación , Trastornos de la Memoria/etiología , Recuerdo Mental , Persona de Mediana Edad
8.
J Clin Exp Neuropsychol ; 43(5): 497-513, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34142928

RESUMEN

Introduction: The rapid development of coronavirus disease 2019 (COVID-19) into a pandemic required people to quickly acquire, evaluate, and apply novel complex health-related information about the virus and transmission risks. This study examined the potentially unique and synergistic roles of individual differences in neurocognition and health literacy in the early uptake and use of COVID-19 public health information.Method: Data were collected between April 23 and 21 May 2020, a period during which 42 out of 50 states were under a stay-at-home order. Participants were 217 healthy adults who completed a telephone-based battery that included standard tests of neurocognition, health literacy, verbal IQ, personality, and anxiety. Participants also completed measures of COVID-19 information-seeking skills, knowledge, prevention intentions, and prevention behaviors.Results: A series of hierarchical multiple regressions with data-driven covariates showed that neurocognition (viz, episodic verbal memory and executive functions) was independently related to COVID-19 knowledge (e.g. symptoms, risks) at a medium effect size, but not to information-seeking skills, prevention intentions, or prevention behaviors. Health literacy was independently related to all measured aspects of COVID-19 health information and did not interact with neurocognition in any COVID-19 health domain.Conclusions: Individual differences in neurocognition and health literacy played independent and meaningful roles in the initial acquisition of knowledge related to COVID-19, which is a novel human health condition. Future studies might examine whether neurocognitive supports (e.g. spaced retrieval practice, elaboration) can improve COVID-19-related knowledge and health behaviors in vulnerable populations.


Asunto(s)
COVID-19 , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Alfabetización en Salud , Individualidad , Adolescente , Adulto , Anciano , COVID-19/epidemiología , Estudios Transversales , Femenino , Salud , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Adulto Joven
9.
Acta Radiol ; 62(9): 1178-1187, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32996322

RESUMEN

BACKGROUND: Ultrasonography is used to evaluate muscle quality (i.e. echo intensity [EI]), but an attenuation of ultrasound waves occurs in deeper tissues, potentially affecting these measures. PURPOSE: To determine whether muscle thickness (MT) affects EI and if EI varies between the superficial and deep portions of the muscle. MATERIALS AND METHODS: MT, EI, subcutaneous adipose tissue thickness (SAT), tissue depth (DISDEEP), and EI of the overall (EIFULL) as well as deep (EIDEEP) and superficial (EISUPF) portions of the vastus lateralis (VL) were assessed in 33 resistance-trained males using ultrasonography. The difference (EIDIFF) between EISUPF and EIDEEP was calculated. Mean differences between EIFULL, EISUPF, and EIDEEP were analyzed using a repeated-measures analysis of variance (ANOVA). Relationships between measures of muscle depth/ thickness and EI were examined using Pearson's r. RESULTS: EISUPF was greater than EIDEEP (P < 0.001) and EIFULL (P < 0.001). MT was negatively correlated with EIFULL (P < 0.001) and positively correlated with EIDIFF (P < 0.001). SAT was not correlated with any EI measure, but DISDEEP was positively correlated with EIDIFF (P < 0.001). CONCLUSION: EI of the VL is heterogeneous, as the deeper portion produces lower values than the superficial portion. Thicker muscles present lower EI but have greater discrepancies in EI between the superficial and deep portions. Although SAT was not correlated with EI, DISDEEP was related to EIDIFF, demonstrating that the combination of MT and SAT should be considered when evaluating muscle quality. Future research is necessary to determine if changes in EI following resistance training are driven by increases in MT.


Asunto(s)
Músculo Cuádriceps/diagnóstico por imagen , Entrenamiento de Fuerza , Ultrasonografía/métodos , Adolescente , Adulto , Humanos , Masculino , Adulto Joven
10.
Arch Clin Neuropsychol ; 36(6): 874-886, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-33236037

RESUMEN

OBJECTIVE: To examine the factor structure and sociodemographic correlates of a battery of clinical neuropsychological tests administered in-home and via telephone. METHOD: Participants included 280 healthy adults who completed a 35-40 min battery consisting of seven auditory-verbal neuropsychological tests (i.e., 10 variables) that included digit span, list learning and memory, prospective memory, verbal fluency, and oral trail making. RESULTS: After removing oral trail making part A, a three-factor model comprised of executive functions, memory and attention demonstrated the best fit to the data. Nevertheless, the shared variance between the nine remaining neuropsychological variables was also adequately explained by a single-factor model and a two-factor model comprised of executive functions and memory. Factor scores were variably associated with education, race/ethnicity, and IQ, but not with sex or age. CONCLUSIONS: Findings provide preliminary support for the feasibility and factor structure and sociodemographic correlates of a brief telephone-based screening neuropsychological battery comprised mostly of commonly administered clinical measures. Future studies are needed to determine the test-retest reliability, sensitivity, and ecological relevance of this battery, as well as equivalency to in-person assessment.


Asunto(s)
Trastornos del Conocimiento , Adulto , Función Ejecutiva , Humanos , Pruebas Neuropsicológicas , Reproducibilidad de los Resultados , Teléfono
11.
J Clin Exp Neuropsychol ; 42(9): 952-964, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33043812

RESUMEN

INTRODUCTION: Older adults with HIV-associated neurocognitive disorders (HAND) are at high risk for deficits in the resource-demanding, strategic aspects of prospective memory (PM) that can adversely affect health outcomes. This study examined the frequency and correlates of spontaneous compensatory strategy use during a laboratory-based PM task and its associations with the use of mnemonic strategies in daily life. METHOD: Participants included 53 older adults with HAND, 89 older persons with HIV without HAND, and 62 seronegatives who completed the Cambridge Prospective Memory Test (CAMPROMPT), on which the type, frequency, and quality of their compensatory strategy use was quantified. Participants also completed self-report measures of PM symptoms and the frequency of mnemonic compensatory strategy use in daily life. RESULT: There were no significant group-level effects on strategy use during the CAMPROMPT. Persons with HAND had moderately lower time-, but not event-based PM scores. Higher compensatory strategy use was strongly associated with better PM, particularly for time-based cues. Moreover, higher compensatory strategy use on the CAMPROMPT was associated with more frequent general mnemonic strategy use in daily life, and specifically with more frequent use of internal PM strategies (e.g., visualization) for medication adherence. CONCLUSION: Spontaneous compensatory mnemonic strategy use can support PM performance among older adults with HAND in the laboratory. Strategy use in the laboratory may be a marker for the extent to which older adults with HAND use other compensatory strategies to support memory in their daily life. Future studies may examine whether compensatory mnemonic strategies can be taught and used to support PM in the daily lives of older persons with HIV disease.


Asunto(s)
Infecciones por VIH/diagnóstico , Memoria Episódica , Trastornos Neurocognitivos/diagnóstico , Medio Social , Anciano , Señales (Psicología) , Femenino , Infecciones por VIH/psicología , Humanos , Masculino , Persona de Mediana Edad , Trastornos Neurocognitivos/psicología , Pruebas Neuropsicológicas
12.
Carbohydr Res ; 495: 108058, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32658832

RESUMEN

G418 is currently the most potent and active aminoglycoside to promote readthrough of eukaryotic nonsense mutations. However, owing to its toxicity G418 cannot be used in vivo to study readthrough activity A robust and scalable method for selective derivatization of G418 was developed to study the biological activity and toxicity of a series of analogs. Despite our synthetic efforts, an improvement in readthrough potency was not achieved. We discovered several analogs that demonstrated reduced zebra fish hair cell toxicity (a surrogate for ototoxicity), but this reduction in cellular toxicity did not translate to reduced in vivo toxicity in rats.


Asunto(s)
Aminoglicósidos/farmacología , Gentamicinas/farmacología , Cabello/efectos de los fármacos , Aminoglicósidos/síntesis química , Aminoglicósidos/química , Animales , Gentamicinas/química , Conformación Molecular , Ratas , Pez Cebra
13.
J Funct Morphol Kinesiol ; 4(3)2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-33467379

RESUMEN

Ultrasonography of the lower body typically encompasses supine rest due to fluid shifts affecting tissue size and composition. However, vastus lateralis (VL) examination is completed in the lateral recumbent position, and this positional change may influence morphology and its ability to predict function. This study aimed to examine the effect of position on VL morphology and its relationship with lower-body performance. Cross-sectional area (CSA), muscle thickness (MT), pennation angle (PA), echo intensity (UnCorEI), subcutaneous adipose tissue thickness (SFT), and echo intensity corrected for SFT (CorEI) were assessed in 31 resistance-trained males (23.0 ± 2.1 yrs; 1.79 ± 0.08 m; 87.4 ± 11.7 kg) immediately after transitioning from standing to supine (IP), after 15 min of standing (ST), and after 15 min of rest in three recumbent positions: supine (SUP), dominant lateral recumbent (DLR), non-dominant lateral recumbent (NDLR). Participants also completed unilateral vertical jumps, isometric/isokinetic tests, and a one-repetition maximum leg press. CSA, MT, PA, and SFT were greater in ST compared to NDLR, DLR, and SUP (p < 0.05). CSA, UnCorEI, and CorEI were different between recumbent positions; however no differences were observed for MT, PA, and SFT. Different magnitudes of relationships were observed between muscle morphological characteristics measured after rest in different positions and performance variables. Muscle morphology in IP generally appears to be the best predictor of performance for most variables, although utilizing the NDLR and DLR positions may provide comparable results, whereas morphology measured in ST and SUP provide weaker relationships with physical performance. IP also requires less time and fewer requirements on the technician and subject, thus researchers should consider this positioning for VL examination.

14.
PLoS One ; 13(10): e0206158, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30359426

RESUMEN

Nonsense mutations, resulting in a premature stop codon in the open reading frame of mRNAs are responsible for thousands of inherited diseases. Readthrough of premature stop codons by small molecule drugs has emerged as a promising therapeutic approach to treat disorders resulting from premature termination of translation. The aminoglycoside antibiotics are a class of molecule known to promote readthrough at premature termination codons. Gentamicin consists of a mixture of major and minor aminoglycoside components. Here, we investigated the readthrough activities of the individual components and show that each of the four major gentamicin complex components representing 92-99% of the complex each had similar potency and activity to that of the complex itself. In contrast, a minor component (gentamicin X2) was found to be the most potent and active readthrough component in the gentamicin complex. The known oto- and nephrotoxicity associated with aminoglycosides preclude long-term use as readthrough agents. Thus, we evaluated the components of the gentamicin complex as well as the so-called "designer" aminoglycoside, NB124, for in vitro and in vivo safety. In cells, we observed that gentamicin X2 had a safety/readthrough ratio (cytotoxicity/readthrough potency) superior to that of gentamicin, G418 or NB124. In rodents, we observed that gentamicin X2 showed a safety profile that was superior to G418 overall including reduced nephrotoxicity. These results support further investigation of gentamicin X2 as a therapeutic readthrough agent.


Asunto(s)
Codón sin Sentido/síntesis química , Enfermedades Genéticas Congénitas/tratamiento farmacológico , Gentamicinas/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Aminoglicósidos/farmacología , Aminoglicósidos/uso terapéutico , Animales , Antibióticos Antineoplásicos/farmacología , Células Cultivadas , Codón de Terminación/síntesis química , Embrión no Mamífero , Gentamicinas/química , Gentamicinas/uso terapéutico , Humanos , Enfermedades Renales/inducido químicamente , Enfermedades Renales/patología , Masculino , Sistemas de Lectura Abierta/efectos de los fármacos , Sistemas de Lectura Abierta/genética , Inhibidores de la Síntesis de la Proteína/uso terapéutico , Ratas , Ratas Sprague-Dawley , Pez Cebra/embriología
15.
RNA ; 23(4): 567-577, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28096517

RESUMEN

Nonsense mutations resulting in a premature stop codon in an open reading frame occur in critical tumor suppressor genes in a large number of the most common forms of cancers and are known to cause or contribute to the progression of disease. Low molecular weight compounds that induce readthrough of nonsense mutations offer a new means of treating patients with genetic disorders or cancers resulting from nonsense mutations. We have identified the nucleoside analog clitocine as a potent and efficacious suppressor of nonsense mutations. We determined that incorporation of clitocine into RNA during transcription is a prerequisite for its readthrough activity; the presence of clitocine in the third position of a premature stop codon directly induces readthrough. We demonstrate that clitocine can induce the production of p53 protein in cells harboring p53 nonsense-mutated alleles. In these cells, clitocine restored production of full-length and functional p53 as evidenced by induced transcriptional activation of downstream p53 target genes, progression of cells into apoptosis, and impeded growth of nonsense-containing human ovarian cancer tumors in xenograft tumor models. Thus, clitocine induces readthrough of nonsense mutations by a previously undescribed mechanism and represents a novel therapeutic modality to treat cancers and genetic diseases caused by nonsense mutations.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Materiales Biomiméticos/farmacología , Codón sin Sentido/efectos de los fármacos , Furanos/farmacología , Nucleósidos/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Nucleósidos de Pirimidina/farmacología , Proteína p53 Supresora de Tumor/agonistas , Animales , Antimetabolitos Antineoplásicos/síntesis química , Antimetabolitos Antineoplásicos/metabolismo , Apoptosis/efectos de los fármacos , Materiales Biomiméticos/síntesis química , Materiales Biomiméticos/metabolismo , Línea Celular Tumoral , Femenino , Furanos/síntesis química , Furanos/metabolismo , Genes Reporteros , Humanos , Luciferasas/genética , Luciferasas/metabolismo , Ratones , Ratones Desnudos , Nucleósidos/síntesis química , Nucleósidos/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Biosíntesis de Proteínas , Nucleósidos de Pirimidina/síntesis química , Nucleósidos de Pirimidina/metabolismo , Transducción de Señal , Activación Transcripcional , Carga Tumoral/efectos de los fármacos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Proc Natl Acad Sci U S A ; 113(44): 12508-12513, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27702906

RESUMEN

A premature termination codon (PTC) in the ORF of an mRNA generally leads to production of a truncated polypeptide, accelerated degradation of the mRNA, and depression of overall mRNA expression. Accordingly, nonsense mutations cause some of the most severe forms of inherited disorders. The small-molecule drug ataluren promotes therapeutic nonsense suppression and has been thought to mediate the insertion of near-cognate tRNAs at PTCs. However, direct evidence for this activity has been lacking. Here, we expressed multiple nonsense mutation reporters in human cells and yeast and identified the amino acids inserted when a PTC occupies the ribosomal A site in control, ataluren-treated, and aminoglycoside-treated cells. We find that ataluren's likely target is the ribosome and that it produces full-length protein by promoting insertion of near-cognate tRNAs at the site of the nonsense codon without apparent effects on transcription, mRNA processing, mRNA stability, or protein stability. The resulting readthrough proteins retain function and contain amino acid replacements similar to those derived from endogenous readthrough, namely Gln, Lys, or Tyr at UAA or UAG PTCs and Trp, Arg, or Cys at UGA PTCs. These insertion biases arise primarily from mRNA:tRNA mispairing at codon positions 1 and 3 and reflect, in part, the preferred use of certain nonstandard base pairs, e.g., U-G. Ataluren's retention of similar specificity of near-cognate tRNA insertion as occurs endogenously has important implications for its general use in therapeutic nonsense suppression.


Asunto(s)
Codón sin Sentido/genética , Oxadiazoles/farmacología , ARN de Transferencia/genética , Ribosomas/efectos de los fármacos , Células HEK293 , Humanos , Biosíntesis de Proteínas/efectos de los fármacos , Estabilidad del ARN/efectos de los fármacos , ARN de Transferencia/metabolismo , Ribosomas/genética , Ribosomas/metabolismo , Transcripción Genética/efectos de los fármacos
17.
Biol Reprod ; 86(6): 191, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22423048

RESUMEN

Mouse and human pregnancy-specific glycoproteins (PSG) are known to exert immunomodulatory functions during pregnancy by inducing maternal leukocytes to secrete anti-inflammatory cytokines that promote a tolerogenic decidual microenvironment. Many such anti-inflammatory mediators also function as proangiogenic factors, which, along with the reported association of murine PSG with the uterine vasculature, suggest that PSG may contribute to the vascular adaptations necessary for successful implantation and placental development. We observed that PSG22 is strongly expressed around the embryonic crypt on Gestation Day 5.5, indicating that trophoblast giant cells are the main source of PSG22 during the early stages of pregnancy. PSG22 treatment up-regulated the secretion of transforming growth factor beta 1 and vascular endothelial growth factor A (VEGFA) in murine macrophages, uterine dendritic cells, and natural killer cells. A possible role of PSGs in uteroplacental angiogenesis is further supported by the finding that incubation of endothelial cells with PSG22 resulted in the formation of tubes in the presence and absence of VEGFA. We determined that PSG22, like human PSG1 and murine PSG17 and PSG23, binds to the heparan sulfate chains in syndecans. Therefore, our findings indicate that despite the independent evolution and expansion of human and rodent PSG, members in both families have conserved functions that include their ability to induce anti-inflammatory cytokines and proangiogenic factors as well as to induce the formation of capillary structures by endothelial cells. In summary, our results indicate that PSG22, the most abundant PSG expressed during mouse early pregnancy, is likely a major contributor to the establishment of a successful pregnancy.


Asunto(s)
Glicoproteínas/metabolismo , Neovascularización Fisiológica , Proteínas Gestacionales/metabolismo , Preñez/metabolismo , Trofoblastos/metabolismo , Animales , Células CHO , Cricetinae , Cricetulus , Células Dendríticas/metabolismo , Femenino , Células Asesinas Naturales/metabolismo , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Embarazo , Preñez/inmunología , Proteínas Recombinantes/metabolismo , Sindecanos/metabolismo , Tetraspanina 29/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
18.
Biol Reprod ; 79(6): 1054-61, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18753609

RESUMEN

Haemochorial placentation is a unique physiological process in which the fetal trophoblast cells remodel the maternal decidual spiral arteries to establish the fetoplacental blood supply. Pregnancy-specific glycoproteins (PSGs) are members of the carcinoembryonic antigen family. PSGs are produced by the placenta of rodents and primates and are secreted into the bloodstream. PSG23 is one of 17 members of the murine PSG family (designated PSG16 to PSG32). Previous studies determined that PSGs have immunoregulatory functions due to their ability to modulate macrophage cytokine secretion. Here we show that recombinant PSG23 induces transforming growth factor (TGF) beta1, TGFB1, and vascular endothelial growth factor A (VEGFA) in primary murine macrophages and the macrophage cell line RAW 264.7 cells. In addition, we identified new cell types that responded to PSG23 treatment. Dendritic cells, endothelial cells, and trophoblasts, which are involved in maternal vasculature remodeling during pregnancy, secreted TGFB1 and VEGFA in response to PSG23. PSG23 showed cross-reactivity with human cells, including human monocytes and the trophoblast cell line, HTR-8/SVneo cells. We analyzed the binding of PSG23 to the tetraspanin CD9, the receptor for PSG17, and found that CD9 is not essential for PSG23 binding and activity in macrophages. Overall these studies show that PSGs can modulate the secretion of important proangiogenic factors, TGFB1 and VEGFA, by different cell types involved in the development of the placenta.


Asunto(s)
Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/fisiología , Glicoproteínas/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Proteínas Gestacionales/farmacología , Preñez/fisiología , Factor de Crecimiento Transformador beta1/biosíntesis , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Animales , Especificidad de Anticuerpos , Western Blotting , Línea Celular , Células Dendríticas/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Glicoproteínas/genética , Glicoproteínas/fisiología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica/genética , Plásmidos/genética , Embarazo , Proteínas Gestacionales/genética , Proteínas Gestacionales/fisiología , Recombinación Genética , Transfección , Trofoblastos/fisiología
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