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1.
Cell ; 186(9): 1985-2001.e19, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37075754

RESUMEN

Aneuploidy, the presence of chromosome gains or losses, is a hallmark of cancer. Here, we describe KaryoCreate (karyotype CRISPR-engineered aneuploidy technology), a system that enables the generation of chromosome-specific aneuploidies by co-expression of an sgRNA targeting chromosome-specific CENPA-binding ɑ-satellite repeats together with dCas9 fused to mutant KNL1. We design unique and highly specific sgRNAs for 19 of the 24 chromosomes. Expression of these constructs leads to missegregation and induction of gains or losses of the targeted chromosome in cellular progeny, with an average efficiency of 8% for gains and 12% for losses (up to 20%) validated across 10 chromosomes. Using KaryoCreate in colon epithelial cells, we show that chromosome 18q loss, frequent in gastrointestinal cancers, promotes resistance to TGF-ß, likely due to synergistic hemizygous deletion of multiple genes. Altogether, we describe an innovative technology to create and study chromosome missegregation and aneuploidy in the context of cancer and beyond.


Asunto(s)
Centrómero , Técnicas Genéticas , Humanos , Aneuploidia , Centrómero/genética , Deleción Cromosómica , Neoplasias/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas
2.
Proc Natl Acad Sci U S A ; 119(47): e2213835119, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36395141

RESUMEN

Somatic copy number alterations (SCNAs), generally (1) losses containing interferons and interferon-pathway genes, many on chromosome 9p, predict immune-cold, immune checkpoint therapy (ICT)-resistant tumors (2); however, genomic regions mediating these effects are unclear and probably tissue specific. Previously, 9p21.3 loss was found to be an early genetic driver of human papillomavirus-negative (HPV-) head and neck squamous cancer (HNSC), associated with an immune-cold tumor microenvironment (TME) signal, and recent evidence suggested that this TME-cold phenotype was greatly enhanced with 9p21 deletion size, notably encompassing band 9p24.1 (3). Here, we report multi-omic, -threshold and continuous-variable dissection of 9p21 and 9p24 loci (including depth and degree of somatic alteration of each band at each locus, and each gene at each band) and TME of four HPV- HNSC cohorts. Preferential 9p24 deletion, CD8 T-cell immune-cold associations were observed, driven by 9p24.1 loss, and in turn by an essential telomeric regulatory gene element, JAK2-CD274. Surprisingly, same genetic region gains were immune hot. Related 9p21-TME analyses were less evident. Inherent 9p-band-level influences on anti-PD1 ICT survival rates, coincident with TME patterns, were also observed. At a 9p24.1 whole-transcriptome expression threshold of 60th percentile, ICT survival rate exceeded that of lower expression percentiles and of chemotherapy; below this transcript threshold, ICT survival was inferior to chemotherapy, the latter unaffected by 9p24.1 expression level (P-values < 0.01, including in a PD-L1 immunohistochemistry-positive patient subgroup). Whole-exome analyses of 10 solid-tumor types suggest that these 9p-related ICT findings could be relevant to squamous cancers, in which 9p24.1 gain/immune-hot associations exist.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Humanos , Microambiente Tumoral/genética , Inhibidores de Puntos de Control Inmunológico , Infecciones por Papillomavirus/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/genética
3.
J Neurosci ; 43(50): 8769-8776, 2023 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-37875376

RESUMEN

Many objects in the real world have features that vary over time, creating uncertainty in how they will look in the future. This uncertainty makes statistical knowledge about the likelihood of features critical to attention demanding processes such as visual search. However, little is known about how the uncertainty of visual features is integrated into predictions about search targets in the brain. In the current study, we test the idea that regions prefrontal cortex code statistical knowledge about search targets before the onset of search. Across 20 human participants (13 female; 7 male), we observe target identity in the multivariate pattern and uncertainty in the overall activation of dorsolateral prefrontal cortex (DLPFC) and inferior frontal junction (IFJ) in advance of the search display. This indicates that the target identity (mean) and uncertainty (variance) of the target distribution are coded independently within the same regions. Furthermore, once the search display appears the univariate IFJ signal scaled with the distance of the actual target from the expected mean, but more so when expected variability was low. These results inform neural theories of attention by showing how the prefrontal cortex represents both the identity and expected variability of features in service of top-down attentional control.SIGNIFICANCE STATEMENT Theories of attention and working memory posit that when we engage in complex cognitive tasks our performance is determined by how precisely we remember task-relevant information. However, in the real world the properties of objects change over time, creating uncertainty about many aspects of the task. There is currently a gap in our understanding of how neural systems represent this uncertainty and combine it with target identity information in anticipation of attention demanding cognitive tasks. In this study, we show that the prefrontal cortex represents identity and uncertainty as unique codes before task onset. These results advance theories of attention by showing that the prefrontal cortex codes both target identity and uncertainty to implement top-down attentional control.


Asunto(s)
Atención , Corteza Prefrontal , Humanos , Masculino , Femenino , Incertidumbre , Estimulación Luminosa/métodos , Corteza Prefrontal/fisiología , Atención/fisiología , Memoria a Corto Plazo
4.
Mem Cognit ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530622

RESUMEN

Boundary contraction and extension are two types of scene transformations that occur in memory. In extension, viewers extrapolate information beyond the edges of the image, whereas in contraction, viewers forget information near the edges. Recent work suggests that image composition influences the direction and magnitude of boundary transformation. We hypothesize that selective attention at encoding is an important driver of boundary transformation effects, selective attention to specific objects at encoding leading to boundary contraction. In this study, one group of participants (N = 36) memorized 15 scenes while searching for targets, while a separate group (N = 36) just memorized the scenes. Both groups then drew the scenes from memory with as much object and spatial detail as they could remember. We asked online workers to provide ratings of boundary transformations in the drawings, as well as how many objects they contained and the precision of remembered object size and location. We found that search condition drawings showed significantly greater boundary contraction than drawings of the same scenes in the memorize condition. Search drawings were significantly more likely to contain target objects, and the likelihood to recall other objects in the scene decreased as a function of their distance from the target. These findings suggest that selective attention to a specific object due to a search task at encoding will lead to significant boundary contraction.

5.
Mem Cognit ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831161

RESUMEN

Multisensory object processing improves recognition memory for individual objects, but its impact on memory for neighboring visual objects and scene context remains largely unknown. It is therefore unclear how multisensory processing impacts episodic memory for information outside of the object itself. We conducted three experiments to test the prediction that the presence of audiovisual objects at encoding would improve memory for nearby visual objects, and improve memory for the environmental context in which they occurred. In Experiments 1a and 1b, participants viewed audiovisual-visual object pairs or visual-visual object pairs with a control sound during encoding and were subsequently tested on their memory for each object individually. In Experiment 2, objects were paired with semantically congruent or meaningless control sounds and appeared within four different scene environments. Memory for the environment was tested. Results from Experiments 1a and 1b showed that encoding a congruent audiovisual object did not significantly benefit memory for neighboring visual objects, but Experiment 2 showed that encoding a congruent audiovisual object did improve memory for the environments in which those objects were encoded. These findings suggest that multisensory processing can influence memory beyond the objects themselves and that it has a unique role in episodic memory formation. This is particularly important for understanding how memories and associations are formed in real-world situations, in which objects and their surroundings are often multimodal.

6.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33952700

RESUMEN

An aneuploid-immune paradox encompasses somatic copy-number alterations (SCNAs), unleashing a cytotoxic response in experimental precancer systems, while conversely being associated with immune suppression and cytotoxic-cell depletion in human tumors, especially head and neck cancer (HNSC). We present evidence from patient samples and cell lines that alterations in chromosome dosage contribute to an immune hot-to-cold switch during human papillomavirus-negative (HPV-) head and neck tumorigenesis. Overall SCNA (aneuploidy) level was associated with increased CD3+ and CD8+ T cell microenvironments in precancer (mostly CD3+, linked to trisomy and aneuploidy), but with T cell-deficient tumors. Early lesions with 9p21.3 loss were associated with depletion of cytotoxic T cell infiltration in TP53 mutant tumors; and with aneuploidy were associated with increased NK-cell infiltration. The strongest driver of cytotoxic T cell and Immune Score depletion in oral cancer was 9p-arm level loss, promoting profound decreases of pivotal IFN-γ-related chemokines (e.g., CXCL9) and pathway genes. Chromosome 9p21.3 deletion contributed mainly to cell-intrinsic senescence suppression, but deletion of the entire arm was necessary to diminish levels of cytokine, JAK-STAT, and Hallmark NF-κB pathways. Finally, 9p arm-level loss and JAK2-PD-L1 codeletion (at 9p24) were predictive markers of poor survival in recurrent HPV- HNSC after anti-PD-1 therapy; likely amplified by independent aneuploidy-induced immune-cold microenvironments observed here. We hypothesize that 9p21.3 arm-loss expansion and epistatic interactions allow oral precancer cells to acquire properties to overcome a proimmunogenic aneuploid checkpoint, transform and invade. These findings enable distinct HNSC interception and precision-therapeutic approaches, concepts that may apply to other CN-driven neoplastic, immune or aneuploid diseases, and immunotherapies.


Asunto(s)
Aneuploidia , Deleción Cromosómica , Neoplasias de Cabeza y Cuello/genética , Evasión Inmune , Infecciones por Papillomavirus , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1 , Complejo CD3 , Linfocitos T CD8-positivos , Línea Celular Tumoral , Cromosomas , Citocinas , Variaciones en el Número de Copia de ADN , Regulación Neoplásica de la Expresión Génica , Genes p53/genética , Humanos , Evasión Inmune/genética , Inmunoterapia , Janus Quinasa 2 , Persona de Mediana Edad , Infecciones por Papillomavirus/genética , Linfocitos T Citotóxicos , Microambiente Tumoral , Adulto Joven
7.
BMC Med Educ ; 24(1): 323, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515122

RESUMEN

BACKGROUND: Most United States medical schools have affiliated student-run free clinics, but the quality of services provided in such contexts compared to national metrics is unknown. This study determines whether a student-run, attending-supervised free clinic servicing a low-income and minority race patient population in New York City can meet national metrics of care. METHODS: Through chart review from January 1, 2020 to December 31, 2020, patient outcomes and service utilization in the Healthcare Effectiveness Data and Information Set were examined and compared to national rates of patients using Medicaid HMO or Medicare. Patients are ≥ 21 years of age, residents of East Harlem, and ineligible for health insurance because of legal residency requirements. The majority identify as Hispanic and speak Spanish as their primary language. All patients who were seen in the clinic during the 2020 calendar year were included. The primary study outcome is the number of Healthcare Effectiveness Data and Information Set measures in which patients, seen in a student-run free clinic, meet or exceed national comparisons. RESULTS: The healthcare outcomes of 238 patients, mean age 47.8 years and 54.6% female, were examined in 18 Healthcare Effectiveness Data and Information Set measures. The student-run free clinic met or exceeded national metrics in 16 out of 18 categories. CONCLUSIONS: The student-run free clinic met or exceeded the national standard of care according to national metrics. Evidence-based priorities have been clarified for future improvement. Other student-run free clinics should similarly evaluate the quality of their services.


Asunto(s)
Clínica Administrada por Estudiantes , Estudiantes de Medicina , Humanos , Femenino , Anciano , Estados Unidos , Persona de Mediana Edad , Masculino , Medicare , Instituciones de Atención Ambulatoria , Evaluación de Resultado en la Atención de Salud
8.
Clin Gastroenterol Hepatol ; 21(11): 2759-2788.e6, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36549469

RESUMEN

BACKGROUND & AIMS: Structural racism and discrimination (SRD) are important upstream determinants of health perpetuated by discriminatory laws and policies. Therefore, measuring SRD and its impact on health is critical to developing interventions that address resultant health disparities. We aimed to identify gastrointestinal (GI) or liver studies that report measures of SRD or interventions to achieve health equity in these domains by addressing upstream determinants of health. METHODS: We conducted a scoping review according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses scoping reviews guidelines. Studies that used an SRD measure or examined an upstream intervention in GI or liver disease were included. Studies that described health disparities in GI or liver conditions without mentioning SRD were excluded. Study characteristics, findings, and limitations were extracted. RESULTS: Forty-six articles (19 studies using SRD measures and 27 studies of upstream interventions) were identified. Measures of residential racial segregation were reported most frequently. SRD was associated with poorer health outcomes for racial and ethnic minority populations. Although upstream intervention studies focused primarily on policies related to colon cancer screening and organ graft allocation, racial and ethnic disparities often persisted post-intervention. CONCLUSIONS: To achieve health equity in GI and liver conditions, there is an urgent need for research that goes beyond describing health disparities to incorporating measures of SRD and implementing interventions that address this understudied determinant of health.


Asunto(s)
Etnicidad , Gastroenterología , Humanos , Disparidades en Atención de Salud , Grupos Minoritarios , Racismo Sistemático
9.
Neural Comput ; 35(11): 1850-1869, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37725708

RESUMEN

Recurrent neural networks (RNNs) are often used to model circuits in the brain and can solve a variety of difficult computational problems requiring memory, error correction, or selection (Hopfield, 1982; Maass et al., 2002; Maass, 2011). However, fully connected RNNs contrast structurally with their biological counterparts, which are extremely sparse (about 0.1%). Motivated by the neocortex, where neural connectivity is constrained by physical distance along cortical sheets and other synaptic wiring costs, we introduce locality masked RNNs (LM-RNNs) that use task-agnostic predetermined graphs with sparsity as low as 4%. We study LM-RNNs in a multitask learning setting relevant to cognitive systems neuroscience with a commonly used set of tasks, 20-Cog-tasks (Yang et al., 2019). We show through reductio ad absurdum that 20-Cog-tasks can be solved by a small pool of separated autapses that we can mechanistically analyze and understand. Thus, these tasks fall short of the goal of inducing complex recurrent dynamics and modular structure in RNNs. We next contribute a new cognitive multitask battery, Mod-Cog, consisting of up to 132 tasks that expands by about seven-fold the number of tasks and task complexity of 20-Cog-tasks. Importantly, while autapses can solve the simple 20-Cog-tasks, the expanded task set requires richer neural architectures and continuous attractor dynamics. On these tasks, we show that LM-RNNs with an optimal sparsity result in faster training and better data efficiency than fully connected networks.

10.
Int J Geriatr Psychiatry ; 38(9): e6000, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37684728

RESUMEN

OBJECTIVE: Depression in patients undergoing coronary artery graft bypass (CABG) surgery is associated with morbidity and mortality, making its early identification and clinical management crucial. Vasculopathy and older age, hallmarks of patients requiring CABG, are also features of vascular depression. In this study, we assess for features of vascular depression in patients undergoing CABG surgery. METHODS: This is a cross-sectional analysis of a single-site prospective observational cohort study of patients undergoing CABG surgery. Subjects were assessed preoperatively using the Depression Interview and Structured Hamilton (DISH), depression scales, transcranial Doppler, neuropsychological testing, and clinical dementia rating (CDR). RESULTS: Of 161 subjects (mean age 66.2 ± 9.3, female 25%) who completed DISH, 18 had major or minor depression, 17 of whom had a past history of major or minor depression (mean age of onset 35.8 years-old). Pre-CABG depression was associated with greater functional impairment on CDR Sum of Boxes (OR = 3.7, 95% CI: 1.4, 9.7) and worse performance on letter fluency test (OR = 0.90, 95% CI: 0.81, 0.99) and trail-making tests (A: OR = 1.06, 95% CI: 1.01, 1.12; B: OR 1.02, 95% CI: 1.01, 1.04). Pre-CABG depression was not associated with middle cerebral artery (MCA) stenosis. CONCLUSIONS: Pre-CABG depression is associated with cognitive and functional impairment similar to vascular depression, but we did not find evidence of an association with older age of onset and MCA stenosis. Further studies on white matter disease in this population are needed to examine the vascular depression hypothesis for pre-CABG depression.


Asunto(s)
Depresión Vascular , Humanos , Femenino , Anciano , Constricción Patológica , Estudios Transversales , Estudios Prospectivos , Puente de Arteria Coronaria/efectos adversos , Cognición
11.
AIDS Res Ther ; 20(1): 43, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37415180

RESUMEN

BACKGROUND: Pre-Exposure Prophylaxis (PrEP) has demonstrated clinical efficacy in preventing HIV infection, yet its uptake remains low. This study, conducted in five PrEP implementing districts in Lesotho, examined factors motivating persons at risk of HIV infection to adopt or reject PrEP when offered freely. METHODS: In-depth interviews were undertaken with stakeholders directly engaged with PrEP policy (n = 5), program implementation (n = 4), and use (current PrEP users = 55, former PrEP users = 36, and PrEP decliners (n = 6)). Focus group discussions (n = 11, 105 total participants) were conducted with health staff directly providing HIV and PrEP services. RESULTS: Demand for PrEP was reported highest among those at greatest risk for HIV acquisition: those in serodiscordant relationships and/or engaged in sex work. Culturally sensitive PrEP counseling was described as an opportunity to transfer knowledge, build trust, and address user concerns. Conversely, top-down counseling resulted in PrEP distrust and confusion about HIV status. Key motivations for PrEP uptake revolved around sustaining core social relationships, desire for safer conception, and caring for ailing relatives. The decline of PrEP initiation was driven by a combination of individual-level factors (risk perception, perceived side effects, disbelief of the drug's efficacy and PrEP's daily pill regimen), societal factors (lack of social support and HIV-related stigma), and structural factors related to PrEP access. CONCLUSIONS: Our findings suggest strategies for effective national PrEP rollout and implementation include: (1) demand creation campaigns which highlight positive aspects of PrEP, while simultaneously addressing apprehensions for uptake; (2) strengthening health provider counseling capacity; and (3) addressing societal and structural HIV-related stigma.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Profilaxis Pre-Exposición/métodos , Lesotho , Motivación , Fármacos Anti-VIH/uso terapéutico
12.
Psychol Sci ; 33(1): 105-120, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34878949

RESUMEN

When searching for a target object, we engage in a continuous "look-identify" cycle in which we use known features of the target to guide attention toward potential targets and then to decide whether the selected object is indeed the target. Target information in memory (the target template or attentional template) is typically characterized as having a single, fixed source. However, debate has recently emerged over whether flexibility in the target template is relational or optimal. On the basis of evidence from two experiments using college students (Ns = 30 and 70, respectively), we propose that initial guidance of attention uses a coarse relational code, but subsequent decisions use an optimal code. Our results offer a novel perspective that the precision of template information differs when guiding sensory selection and when making identity decisions during visual search.


Asunto(s)
Memoria a Corto Plazo , Percepción Visual , Atención , Toma de Decisiones , Humanos , Reconocimiento Visual de Modelos , Tiempo de Reacción
13.
Intern Med J ; 52(3): 440-450, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33012105

RESUMEN

BACKGROUND: Clinical characteristics of women with different obstructive sleep apnoea (OSA) severity and adherence to continuous positive airway pressure (CPAP) therapy have not been previously explored. AIMS: To assess OSA prevalence, predictors, clinical and polysomnographic (PSG) characteristics and adherence to CPAP therapy among adult Australian women in a retrospective study. METHODS: All female patients who underwent a diagnostic PSG between 2014 and 2015 were included. CPAP adherence was assessed during the study period between 2018 and 2019 using multiple regression models. RESULTS: Among a total of 591 women included in this study (Aboriginal, n = 86), OSA was diagnosed in 458/591 (78%) patients; mild, moderate and severe OSA was present in 44%, 27% and 29% respectively. Older age, higher BMI and hypertension predicted the presence and severity of OSA. The Epworth Sleepiness Scale (ESS) score was not significantly different with (8 (5, 12)) or without (10 (5, 13)) OSA. PSG showed the rapid eye movement (REM) sleep-associated apnoea-hypopnea index (AHI) was higher with all severity of OSA. Adherence to CPAP therapy was noted in 171 (57%) patients; 47% mild, 57% moderate and 63% with severe OSA respectively. Three multiple regression models (clinical, PSG parameters, OSA severity, combined (clinical and PSG)) showed the combined model had the strongest predictive value and demonstrated that higher ESS and more severe oxygen desaturation were associated with CPAP adherence irrespective of OSA severity. CONCLUSIONS: Older age, higher BMI and the presence of hypertension predicted the presence of OSA. The REM sleep-related AHI was higher. Adherence to CPAP was associated with symptomatic OSA and severe oxygen desaturation.


Asunto(s)
Hipertensión , Apnea Obstructiva del Sueño , Adulto , Australia/epidemiología , Presión de las Vías Aéreas Positiva Contínua , Femenino , Humanos , Hipertensión/epidemiología , Masculino , Oxígeno , Estudios Retrospectivos , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/terapia
14.
Psychol Res ; 86(6): 2030-2044, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34997327

RESUMEN

Humans are surprisingly good at learning the statistical characteristics of their visual environment. Recent studies have revealed that not only can the visual system learn repeated features of visual search distractors, but also their actual probability distributions. Search times were determined by the frequency of distractor features over consecutive search trials. The search displays applied in these studies involved many exemplars of distractors on each trial and while there is clear evidence that feature distributions can be learned from large distractor sets, it is less clear if distributions are well learned for single targets presented on each trial. Here, we investigated potential learning of probability distributions of single targets during visual search. Over blocks of trials, observers searched for an oddly colored target that was drawn from either a Gaussian or a uniform distribution. Search times for the different target colors were clearly influenced by the probability of that feature within trial blocks. The same search targets, coming from the extremes of the two distributions were found significantly slower during the blocks where the targets were drawn from a Gaussian distribution than from a uniform distribution indicating that observers were sensitive to the target probability determined by the distribution shape. In Experiment 2, we replicated the effect using binned distributions and revealed the limitations of encoding complex target distributions. Our results demonstrate detailed internal representations of target feature distributions and that the visual system integrates probability distributions of target colors over surprisingly long trial sequences.


Asunto(s)
Atención , Aprendizaje , Humanos , Distribución Normal , Probabilidad , Tiempo de Reacción , Percepción Visual
15.
J Insect Sci ; 22(2)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35303100

RESUMEN

Aedes aegypti [Linnaeus in Hasselquist; yellow fever mosquito] transmits several viruses that infect millions of people each year, including Zika, dengue, yellow fever, chikungunya, and West Nile. Pathogen transmission occurs during blood feeding. Only the females blood feed as they require a bloodmeal for oogenesis; in the bloodmeal, holo-transferrin and hemoglobin provide the females with a high iron load. We are interested in the effects of the bloodmeal on the expression of iron-associated proteins in oogenesis. Previous data showed that following digestion of a bloodmeal, ovarian iron concentrations doubles by 72 hr. We have used shotgun proteomics to identify proteins expressed in Ae. aegypti ovaries at two oogenesis developmental stages following blood feeding, and tandem mass tag-labeling proteomics to quantify proteins expressed at one stage following feeding of a controlled iron diet. Our findings provide the first report of mosquito ovarian protein expression in early and late oogenesis. We identify proteins differentially expressed in the two oogenesis development stages. We establish that metal-associated proteins play an important role in Ae. aegypti oogenesis and we identify new candidate proteins that might be involved in mosquito iron metabolism. Finally, this work identified a unique second ferritin light chain subunit, the first reported in any species. The shotgun proteomic data are available via ProteomeXchange with identifier PXD005893, while the tandem mass tag-labeled proteomic data are available with identifier PXD028242.


Asunto(s)
Aedes , Infección por el Virus Zika , Virus Zika , Aedes/metabolismo , Animales , Femenino , Humanos , Hierro/metabolismo , Mosquitos Vectores , Ovario/metabolismo , Proteómica , Virus Zika/metabolismo
16.
J Biol Chem ; 295(40): 13914-13926, 2020 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-32796031

RESUMEN

Aldehyde dehydrogenases are versatile enzymes that serve a range of biochemical functions. Although traditionally considered metabolic housekeeping enzymes because of their ability to detoxify reactive aldehydes, like those generated from lipid peroxidation damage, the contributions of these enzymes to other biological processes are widespread. For example, the plant pathogen Pseudomonas syringae strain PtoDC3000 uses an indole-3-acetaldehyde dehydrogenase to synthesize the phytohormone indole-3-acetic acid to elude host responses. Here we investigate the biochemical function of AldC from PtoDC3000. Analysis of the substrate profile of AldC suggests that this enzyme functions as a long-chain aliphatic aldehyde dehydrogenase. The 2.5 Å resolution X-ray crystal of the AldC C291A mutant in a dead-end complex with octanal and NAD+ reveals an apolar binding site primed for aliphatic aldehyde substrate recognition. Functional characterization of site-directed mutants targeting the substrate- and NAD(H)-binding sites identifies key residues in the active site for ligand interactions, including those in the "aromatic box" that define the aldehyde-binding site. Overall, this study provides molecular insight for understanding the evolution of the prokaryotic aldehyde dehydrogenase superfamily and their diversity of function.


Asunto(s)
Aldehído Deshidrogenasa/química , Proteínas Bacterianas/química , Enfermedades de las Plantas/microbiología , Pseudomonas syringae/enzimología , Aldehído Deshidrogenasa/genética , Proteínas Bacterianas/genética , Cristalografía por Rayos X , Pseudomonas syringae/genética
17.
J Viral Hepat ; 28(6): 934-941, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33720473

RESUMEN

Hepatocellular carcinoma (HCC) is often caused by hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. To investigate the completeness of death certificates for recording viral hepatitis in HCC death, we compared the proportion of HCC deaths with hepatitis virus infection reported on death certificates to that reported as claims in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database among individuals ≥66 years of age. For 2001-2015, we tabulated proportions of HCC deaths with HBV or HCV infection in each database overall, and by demographic factors. To correct for under ascertainment of viral hepatitis-associated HCC on death certificates, we multiplied by the reciprocal ratio of death certificates to SEER-Medicare. Among HCC decedents, HBV infection was reported on 3.6% of death certificates and 17.2% of Medicare claims. For HCV, corresponding proportions were 14.9% and 26.9%. The ratio of HBV-attributable HCC deaths in death certificates to SEER-Medicare remained ~0.21 over time. The ratio of HCV-attributable HCC deaths decreased 22.1% per year, from 0.70 in 2001 to 0.37 in 2003, and increased 4.1% per year, from 0.47 in 2004 to 0.66 in 2015. Following correction, the 2015 mortality rate from death certificate data increased from 0.2 to 0.9 per 100,000 for HBV-attributable HCC and from 2.3 to 3.5 per 100,000 for HCV-attributable HCC. In conclusion, among older Americans dying from HCC, death certificates captured 21% of HBV and 55% of HCV infections compared to Medicare claims. Our results suggest that death certificates provide incomplete data for viral hepatitis-associated HCC surveillance.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B , Hepatitis C , Neoplasias Hepáticas , Anciano , Carcinoma Hepatocelular/epidemiología , Certificado de Defunción , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Hepatitis C/complicaciones , Hepatitis C/epidemiología , Humanos , Neoplasias Hepáticas/epidemiología , Medicare , Estados Unidos/epidemiología
18.
BMC Cancer ; 21(1): 902, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34362338

RESUMEN

BACKGROUND: D-limonene and its derivatives have demonstrated potential chemopreventive and anticancer activity in preclinical and clinical studies. The aim of this scoping review was to assess and critically appraise current literature on the effect of these bioactive citrus peel compounds on breast cancer in human trials and to identify knowledge gaps for exploration in future studies. METHODS: This study followed a scoping review framework. Peer-reviewed journal articles were included if they reported the effect of d-limonene or its derivatives on breast cancer in human subjects. Articles were retrieved from academic databases - PubMed, EMBASE, CINAHL, Web of Science, and Cochrane reviews - and iteratively through review of bibliographies of relevant manuscripts. Titles and abstracts were appraised against the aforementioned inclusion criteria in a first round of screening. Through consensus meetings and full article review by authors, a final set of studies were selected. Results were reported according to the PRISMA extension for scoping reviews. RESULTS: Our search strategy yielded 367 records. Following screening and adjudication, five articles reporting on phase 1(n = 2), phase 2 (n = 2) and both trial phases (n = 1) were included as the final dataset for this review. Trials evaluating the effect of d-limonene (n = 2) showed it was well tolerated in subjects. One study (n = 43 participants) showed d-limonene concentrated in breast tissue (mean 41.3 µg/g tissue) and reduction in tumor cyclin D1 expression, which is associated with tumor proliferation arrest. This study did not show meaningful change in serum biomarkers associated with breast cancer, except for a statistically significant increase in insulin-like growth factor-1 (IGF-I) levels. While elevation of IGF-I is associated with increased cancer risk, the clinical implication of this study remains uncertain given its short duration. Trials with perillyl alcohol (n = 3) showed low tolerance and no effect on breast cancer. CONCLUSION: This review demonstrated a dearth of clinical studies exploring the effect of d-limonene and its derivatives on breast cancer. Limited literature suggests d-limonene is safe and tolerable in human subjects compared to its derivative, perillyl alcohol. Our review demonstrates the need for additional well-powered placebo-controlled trials that assess d-limonene's efficacy on breast cancer compared to other therapies.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Limoneno/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/patología , Terapia Combinada , Monitoreo de Drogas , Femenino , Humanos , Limoneno/química , Limoneno/farmacología , Dosis Máxima Tolerada , Persona de Mediana Edad , Estructura Molecular , Resultado del Tratamiento
19.
Pediatr Nephrol ; 36(10): 3077-3087, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33523298

RESUMEN

Non-invasive technologies to monitor kidney allograft health utilizing high-throughput assays of blood and urine specimens are emerging out of the research realm and slowly becoming part of everyday clinical practice. HLA epitope analysis and eplet mismatch score determination promise a more refined approach to the pre-transplant recipient-donor HLA matching that may lead to reduced rejection risk. High-resolution HLA typing and multiplex single antigen bead assays are identifying potential new offending HLA antibody subtypes. There is increasing recognition of the deleterious role non-HLA antibodies play in post-transplant outcomes. Donor-derived cell-free DNA detected by next-generation sequencing is a promising biomarker for kidney transplant rejection. Multi-omics techniques are shedding light on discrete genomic, transcriptomic, proteomic, and metabolomic signatures that correlate with and predict allograft outcomes. Over the next decade, a comprehensive approach to optimize kidney matching and monitor transplant recipients for acute and chronic graft dysfunction will likely involve a combination of those emerging technologies summarized in this review.


Asunto(s)
Trasplante de Riñón , Rechazo de Injerto/diagnóstico , Supervivencia de Injerto , Antígenos HLA , Prueba de Histocompatibilidad , Humanos , Trasplante de Riñón/efectos adversos , Proteómica
20.
South Med J ; 114(4): 223-230, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33787936

RESUMEN

OBJECTIVES: The purpose of this study was to investigate and identify which sociodemographic factors may be associated with breastfeeding intention and breastfeeding self-efficacy among pregnant women. METHODS: Pregnant women at a medical center in Alabama completed a cross-sectional survey. The Prenatal Rating of Efficacy in Preparation to Breastfeed Scale (PREP to BF) was used to assess prenatal breastfeeding self-efficacy. A valid 3-item breastfeeding intention scale and the Fetal Health Locus of Control Scale also were used. Nonparametric tests were used to assess differences in breastfeeding intention, locus of control subscales, and PREP to BF scores by history with breastfeeding, planned mode of delivery, and sociodemographic factors. RESULTS: The participants in the final analysis (N = 124) had a mean prenatal breastfeeding self-efficacy score of 299.5 (±92.33), with a range of 0 to 390. Significantly lower scores related to intention and PREP to BF were found among Black women (P ≤ 0.05), those with a high school education or less (P ≤ 0.019), single women (P ≤ 0.028), and those who had no breastfeeding experience (P ≤ 0.035). CONCLUSIONS: Identifying pregnant women with low breastfeeding self-efficacy and intention and recognizing the effects of social and cultural influences on breastfeeding are vital. Healthcare providers can engage in meaningful dialog to address ways to increase social support, communication, goal-setting skills, and overcoming mental and emotional barriers.


Asunto(s)
Lactancia Materna/psicología , Intención , Mujeres Embarazadas/psicología , Relaciones Profesional-Paciente , Autoeficacia , Adolescente , Adulto , Alabama , Lactancia Materna/etnología , Estudios Transversales , Femenino , Humanos , Control Interno-Externo , Embarazo , Mujeres Embarazadas/etnología , Autoinforme , Factores Socioeconómicos , Adulto Joven
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