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1.
Cell ; 187(20): 5719-5734.e19, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39299233

RESUMEN

Pathogenic variants in RAD51C confer an elevated risk of breast and ovarian cancer, while individuals homozygous for specific RAD51C alleles may develop Fanconi anemia. Using saturation genome editing (SGE), we functionally assess 9,188 unique variants, including >99.5% of all possible coding sequence single-nucleotide alterations. By computing changes in variant abundance and Gaussian mixture modeling (GMM), we functionally classify 3,094 variants to be disruptive and use clinical truth sets to reveal an accuracy/concordance of variant classification >99.9%. Cell fitness was the primary assay readout allowing us to observe a phenomenon where specific missense variants exhibit distinct depletion kinetics potentially suggesting that they represent hypomorphic alleles. We further explored our exhaustive functional map, revealing critical residues on the RAD51C structure and resolving variants found in cancer-segregating kindred. Furthermore, through interrogation of UK Biobank and a large multi-center ovarian cancer cohort, we find significant associations between SGE-depleted variants and cancer diagnoses.


Asunto(s)
Proteínas de Unión al ADN , Edición Génica , Neoplasias Ováricas , Humanos , Femenino , Edición Génica/métodos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Neoplasias Ováricas/genética , Neoplasias de la Mama/genética , Alelos , Sistemas CRISPR-Cas/genética
2.
Cell ; 187(12): 3024-3038.e14, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38781969

RESUMEN

Plants frequently encounter wounding and have evolved an extraordinary regenerative capacity to heal the wounds. However, the wound signal that triggers regenerative responses has not been identified. Here, through characterization of a tomato mutant defective in both wound-induced defense and regeneration, we demonstrate that in tomato, a plant elicitor peptide (Pep), REGENERATION FACTOR1 (REF1), acts as a systemin-independent local wound signal that primarily regulates local defense responses and regenerative responses in response to wounding. We further identified PEPR1/2 ORTHOLOG RECEPTOR-LIKE KINASE1 (PORK1) as the receptor perceiving REF1 signal for plant regeneration. REF1-PORK1-mediated signaling promotes regeneration via activating WOUND-INDUCED DEDIFFERENTIATION 1 (WIND1), a master regulator of wound-induced cellular reprogramming in plants. Thus, REF1-PORK1 signaling represents a conserved phytocytokine pathway to initiate, amplify, and stabilize a signaling cascade that orchestrates wound-triggered organ regeneration. Application of REF1 provides a simple method to boost the regeneration and transformation efficiency of recalcitrant crops.


Asunto(s)
Proteínas de Plantas , Regeneración , Transducción de Señal , Solanum lycopersicum , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Solanum lycopersicum/metabolismo , Regulación de la Expresión Génica de las Plantas , Péptidos/metabolismo
3.
Nature ; 633(8030): 608-614, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39261734

RESUMEN

Human genetic studies of common variants have provided substantial insight into the biological mechanisms that govern ovarian ageing1. Here we report analyses of rare protein-coding variants in 106,973 women from the UK Biobank study, implicating genes with effects around five times larger than previously found for common variants (ETAA1, ZNF518A, PNPLA8, PALB2 and SAMHD1). The SAMHD1 association reinforces the link between ovarian ageing and cancer susceptibility1, with damaging germline variants being associated with extended reproductive lifespan and increased all-cause cancer risk in both men and women. Protein-truncating variants in ZNF518A are associated with shorter reproductive lifespan-that is, earlier age at menopause (by 5.61 years) and later age at menarche (by 0.56 years). Finally, using 8,089 sequenced trios from the 100,000 Genomes Project (100kGP), we observe that common genetic variants associated with earlier ovarian ageing associate with an increased rate of maternally derived de novo mutations. Although we were unable to replicate the finding in independent samples from the deCODE study, it is consistent with the expected role of DNA damage response genes in maintaining the genetic integrity of germ cells. This study provides evidence of genetic links between age of menopause and cancer risk.


Asunto(s)
Envejecimiento , Predisposición Genética a la Enfermedad , Menopausia , Tasa de Mutación , Neoplasias , Ovario , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Envejecimiento/genética , Envejecimiento/patología , Daño del ADN/genética , Fertilidad/genética , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Genoma Humano/genética , Mutación de Línea Germinal/genética , Menarquia/genética , Menopausia/genética , Neoplasias/genética , Ovario/metabolismo , Ovario/patología , Factores de Tiempo , Biobanco del Reino Unido , Reino Unido/epidemiología
4.
Nature ; 631(8019): 134-141, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38867047

RESUMEN

Mosaic loss of the X chromosome (mLOX) is the most common clonal somatic alteration in leukocytes of female individuals1,2, but little is known about its genetic determinants or phenotypic consequences. Here, to address this, we used data from 883,574 female participants across 8 biobanks; 12% of participants exhibited detectable mLOX in approximately 2% of leukocytes. Female participants with mLOX had an increased risk of myeloid and lymphoid leukaemias. Genetic analyses identified 56 common variants associated with mLOX, implicating genes with roles in chromosomal missegregation, cancer predisposition and autoimmune diseases. Exome-sequence analyses identified rare missense variants in FBXO10 that confer a twofold increased risk of mLOX. Only a small fraction of associations was shared with mosaic Y chromosome loss, suggesting that distinct biological processes drive formation and clonal expansion of sex chromosome missegregation. Allelic shift analyses identified X chromosome alleles that are preferentially retained in mLOX, demonstrating variation at many loci under cellular selection. A polygenic score including 44 allelic shift loci correctly inferred the retained X chromosomes in 80.7% of mLOX cases in the top decile. Our results support a model in which germline variants predispose female individuals to acquiring mLOX, with the allelic content of the X chromosome possibly shaping the magnitude of clonal expansion.


Asunto(s)
Aneuploidia , Cromosomas Humanos X , Células Clonales , Leucocitos , Mosaicismo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Alelos , Enfermedades Autoinmunes/genética , Bancos de Muestras Biológicas , Segregación Cromosómica/genética , Cromosomas Humanos X/genética , Cromosomas Humanos Y/genética , Células Clonales/metabolismo , Células Clonales/patología , Exoma/genética , Proteínas F-Box/genética , Predisposición Genética a la Enfermedad/genética , Mutación de Línea Germinal , Leucemia/genética , Leucocitos/metabolismo , Modelos Genéticos , Herencia Multifactorial/genética , Mutación Missense/genética
5.
Proc Natl Acad Sci U S A ; 120(26): e2220178120, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37339202

RESUMEN

The compositional and thermal state of Earth's mantle provides critical constraints on the origin, evolution, and dynamics of Earth. However, the chemical composition and thermal structure of the lower mantle are still poorly understood. Particularly, the nature and origin of the two large low-shear-velocity provinces (LLSVPs) in the lowermost mantle observed from seismological studies are still debated. In this study, we inverted for the 3D chemical composition and thermal state of the lower mantle based on seismic tomography and mineral elasticity data by employing a Markov chain Monte Carlo framework. The results show a silica-enriched lower mantle with a Mg/Si ratio less than ~1.16, lower than that of the pyrolitic upper mantle (Mg/Si = 1.3). The lateral temperature distributions can be described by a Gaussian distribution with a standard deviation (SD) of 120 to 140 K at 800 to 1,600 km and the SD increases to 250 K at 2,200 km depth. However, the lateral distribution in the lowermost mantle does not follow the Gaussian distribution. We found that the velocity heterogeneities in the upper lower mantle mainly result from thermal anomalies, while those in the lowermost mantle mainly result from compositional or phase variations. The LLSVPs have higher density at the base and lower density above the depth of ~2,700 km than the ambient mantle, respectively. The LLSVPs are found to have ~500 K higher temperature, higher Bridgmanite and iron content than the ambient mantle, supporting the hypothesis that the LLSVPs may originate from an ancient basal magma ocean formed in Earth's early history.

6.
Plant J ; 118(2): 457-468, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38198228

RESUMEN

Carotenoids perform a broad range of important functions in humans; therefore, carotenoid biofortification of maize (Zea mays L.), one of the most highly produced cereal crops worldwide, would have a global impact on human health. PLASTID TERMINAL OXIDASE (PTOX) genes play an important role in carotenoid metabolism; however, the possible function of PTOX in carotenoid biosynthesis in maize has not yet been explored. In this study, we characterized the maize PTOX locus by forward- and reverse-genetic analyses. While most higher plant species possess a single copy of the PTOX gene, maize carries two tandemly duplicated copies. Characterization of mutants revealed that disruption of either copy resulted in a carotenoid-deficient phenotype. We identified mutations in the PTOX genes as being causal of the classic maize mutant, albescent1. Remarkably, overexpression of ZmPTOX1 significantly improved the content of carotenoids, especially ß-carotene (provitamin A), which was increased by ~threefold, in maize kernels. Overall, our study shows that maize PTOX locus plays an important role in carotenoid biosynthesis in maize kernels and suggests that fine-tuning the expression of this gene could improve the nutritional value of cereal grains.


Asunto(s)
Oxidorreductasas , Zea mays , Humanos , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Zea mays/genética , Zea mays/metabolismo , Carotenoides/metabolismo , beta Caroteno/metabolismo , Grano Comestible/genética , Grano Comestible/metabolismo , Plastidios/genética , Plastidios/metabolismo
7.
EMBO Rep ; 24(4): e56524, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-36802267

RESUMEN

We report the identification of a cell population that shares pericyte, stromal and stemness features, does not harbor the KrasG12D mutation and drives tumoral growth in vitro and in vivo. We term these cells pericyte stem cells (PeSCs) and define them as CD45- EPCAM- CD29+ CD106+ CD24+ CD44+ cells. We perform studies with p48-Cre;KrasG12D (KC), pdx1-Cre;KrasG12D ;Ink4a/Arffl/fl (KIC) and pdx1-Cre;KrasG12D ;p53R172H (KPC) and tumor tissues from PDAC and chronic pancreatitis patients. We also perform single-cell RNAseq analysis and reveal a unique signature of PeSC. Under steady-state conditions, PeSCs are barely detectable in the pancreas but present in the neoplastic microenvironment both in humans and mice. The coinjection of PeSCs and tumor epithelial cells leads to increased tumor growth, differentiation of Ly6G+ myeloid-derived suppressor cells, and a decreased amount of F4/80+ macrophages and CD11c+ dendritic cells. This population induces resistance to anti-PD-1 immunotherapy when coinjected with epithelial tumor cells. Our data reveal the existence of a cell population that instructs immunosuppressive myeloid cell responses to bypass PD-1 targeting and thus suggest potential new approaches for overcoming resistance to immunotherapy in clinical settings.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Humanos , Ratones , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/genética , Pericitos , Proteínas Proto-Oncogénicas p21(ras) , Células Madre , Microambiente Tumoral , Neoplasias Pancreáticas
8.
Oncologist ; 29(7): e877-e886, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38537665

RESUMEN

BACKGROUND: According to the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) criteria, both immunohistochemical HER2 (3+) and HER2 (2+)/in situ hybridization (ISH) amplified [HER2 (2+)/ISH+] breast cancers (BCs) fall under the HER2-positive BC category. However, there is a lack of studies exploring the difference of neoadjuvant therapeutic response between patients with HER2 (3+) and HER2 (2+)/ISH+ early BC. We aimed to evaluate the neoadjuvant therapeutic response, long-term outcome, and intrinsic subtype heterogeneity between HER2 (3+) and HER2 (2+)/ISH+ BC. METHODS: We examined 2 distinct cohorts. Cohort 1 (C1) encompassed 2648 patients with HER2-positive early BC diagnoses, and they received neoadjuvant therapy (NT) and surgery between January 1, 2009 and December 31, 2022, from the Shanghai Jiao Tong University Breast Cancer Data Base. Cohort 2 (C2) comprised 135 patients with early-stage HER2-positive BC who underwent NT and surgery at Henan Cancer Hospital from January 1, 2021, to December 31, 2022. These patients had available genomic and transcriptomic data at their disposal. C1 and C2 were further categorized into 2 patient cohorts as follows: (1) patients with IHC HER2 (3+) early BC [HER2 (3+) group], (2) patients with HER2 (2+)/ISH+ early BC [HER2 (2+)/ISH+ group]. Among those excluded from the analysis were patients < 18 years or >80 years of age. Clinicopathological parameters, long-term outcomes, and intrinsic subtypes were analyzed. RESULTS: In the C1 population, 83.7% had HER2 (3+) BC, while 16.3% had HER2 (2+)/ISH+ BC. Patients with HER2 (3+) had a significantly higher pathological complete response (PCR) rate (38.9%) than patients with HER2 (2+)/ISH+ (18.1%; P < .001), but the disease-free survival (DFS) was comparable after a median follow-up of 29 months (P = .556). The addition of trastuzumab or trastuzumab plus pertuzumab to neoadjuvant chemotherapy (NAC) improved PCR rates and DFS in HER2 (3+) BC but not in HER2 (2+)/ISH+ BC. In the C2 population, 97.75% HER2 (3+) and 52.17% HER2 (2+)/ISH+ were HER2 enriched (HER2E) subtype (P < .001). HER2E showed increased PCR rates compared to non-HER2E (P = .004). CONCLUSIONS: Compared to HER2 (3+) BC, the limited effectiveness of neoadjuvant trastuzumab and pertuzumab therapy for HER2 (2+)/ISH+ BC is due to subtype heterogeneity. Reassessment of targeted therapy efficacy in patients with HER2 (2+)/ISH+ BC is essential.


Asunto(s)
Neoplasias de la Mama , Terapia Neoadyuvante , Receptor ErbB-2 , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Femenino , Terapia Neoadyuvante/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Receptor ErbB-2/metabolismo , Adulto , Inmunohistoquímica/métodos , Anciano , Estadificación de Neoplasias
9.
Eur J Nucl Med Mol Imaging ; 51(2): 369-379, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37759096

RESUMEN

PURPOSE: PD-L1 PET imaging, as a non-invasive procedure, can perform a real-time, dynamic and quantitative analysis of PD-L1 expression at tumor sites. In this study, we developed a novel peptide-based PET tracer, [68 Ga]Ga-AUNP-12, for preclinical and first-of-its-kind imaging of PD-L1 expression in patients. METHODS: Radiosynthesis of [68 Ga]Ga-AUNP-12 was conducted. Assays for cellular uptake and binding were conducted on the PANC02, CT26, and B16F10 cell lines. Preclinical models were used to investigate its biodistribution, imaging capacity, and pharmacokinetics. Furthermore, interferon-γ (IFN-γ) was used for development of an animal model with high PD-L1 expression for targeted PET imaging and efficacy evaluation of PD-L1 blocking therapy. In healthy volunteers and cancer patients, the PD-L1 imaging, radiation dosimetry, safety, and biodistribution were further evaluated. RESULTS: In vitro and in vivo animal studies showed that [68 Ga]Ga-AUNP-12 PET imaging displayed a high specificity in evaluating PD-L1 expression. The radiochemical yield of [68 Ga]Ga-AUNP-12 was 71.7 ± 8.2%. Additionally, its molar activity and radiochemical purity were satisfactory. The B16F10 tumor was visualized with the tumor uptake of 6.86 ± 0.71% ID/g and tumor-to-muscle ratio of 6.83 ± 0.36 at 60 min after [68 Ga]Ga-AUNP-12 injection. Furthermore, [68 Ga]Ga-AUNP-12 PET imaging could sensitively detect the PD-L1 dynamic changes in CT26 tumor xenograft models regulated by IFN-γ treatment, and correspondingly can effectively guide immunotherapy. Regarding radiation dosimetry, [68 Ga]Ga-AUNP-12 is safe for human use. The first human study found that [68 Ga]Ga-AUNP-12 can be rapidly cleared from blood and other nonspecific organs through the kidney excretion, leading to form a clear imaging contrast in the clinical framework. The specificity of [68 Ga]Ga-AUNP-12 was validated and tumor uptake strongly correlated with the high PD-L1 expression in patients with lung adenocarcinoma and oesophageal squamous cell carcinoma (OSCC). CONCLUSION: [68 Ga]Ga-AUNP-12 was successfully developed as a PD-L1-specific PET imaging tracer in preclinical and first-in-human studies.


Asunto(s)
Radioisótopos de Galio , Neoplasias , Humanos , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos/farmacocinética , Distribución Tisular
10.
Br J Nutr ; 131(1): 134-142, 2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-37462503

RESUMEN

The rate of adult severe obesity has been continually rising in the USA. While improving diet quality has been shown to reduce the risk of obesity, few studies have explored the differences in diet quality among adults with overweight and obesity by different weight statuses along with socio-demographic factors and physical activity using data from a nationally representative survey in the USA. The main goal of the study is to assess the diet quality of adults with overweight and obesity by examining differences in the Healthy Eating Index-2015 (HEI-2015) scores, using data from the 2015-2018 National Health and Nutrition Survey. Among 6746 adults with overweight and obesity (aged ≥ 20 years), severe obesity was prevalent (27 %), particularly among females, non-Hispanic Blacks and those with lower education and income. Compared to adults with overweight, adults with severe obesity had lower HEI-2015 total scores as well as component scores for total fruits, whole fruits, greens and beans, refined grains, sodium and saturated fats. Among adults with overweight and obesity, non-Hispanic Blacks had lower diet quality than non-Hispanic Asians; females had better diet quality than males; older adults had better diet quality than younger adults; adults with a college degree and above had better diet quality than those with less than a high school degree. Socio-demographic differences in diet quality and weight status should be considered in future obesity interventions to reduce adult severe obesity in the USA.


Asunto(s)
Obesidad Mórbida , Sobrepeso , Masculino , Femenino , Humanos , Anciano , Sobrepeso/epidemiología , Encuestas Nutricionales , Dieta , Obesidad/epidemiología
11.
BMC Cardiovasc Disord ; 24(1): 503, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300340

RESUMEN

AIMS: To explore the effect of early initiation of self-management based on multidisciplinary education in heart failure (HF) patients. METHODS: HF patients in the Cardiology Department of Beijing Hospital were consecutively enrolled from June 2022 to February 2023. In-hospital HF patients from June 2022 to October 2022 were divided into the control group, and HF patients from November 2022 to February 2023 were divided into the cardiac rehabilitation (CR) group. A series of self-management education sessions with cardiologists, pharmacologists, nutritionists, and nurses was initiated early in the CR group. Continuous strengthening education was provided during the 3 months of discharge. Patients in the control group only received education twice during hospitalization. Minnesota Living with Heart Failure Questionnaire (MLHFQ), Pittsburgh sleep quality index (PSQI), anxiety Self-rating anxiety scale (SAS), and Self-rating depression scale (SDS) were compared between the two groups. Major cardiovascular adverse events (MACEs) were recorded during follow-up. RESULTS: A total of 91 HF patients were enrolled. There were 44 patients in the CR group and 47 in the control group. Compared with before the program, the MLHFQ and SAS scores significantly decreased at 3 months after discharge in both groups. PSQI also showed mild improvement without significant differences in both groups. Furthermore, SDS showed a significant increase in the CR group but within the normal range. MACE occurrences did not show a significant difference. CONCLUSION: Early initiation of self-management program based on multidisciplinary education may help improve quality of life, sleep quality, and reduce anxiety for hospitalized HF patients.


Asunto(s)
Rehabilitación Cardiaca , Insuficiencia Cardíaca , Educación del Paciente como Asunto , Calidad de Vida , Automanejo , Humanos , Masculino , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/rehabilitación , Insuficiencia Cardíaca/mortalidad , Persona de Mediana Edad , Anciano , Rehabilitación Cardiaca/métodos , Factores de Tiempo , Resultado del Tratamiento , Autocuidado , Grupo de Atención al Paciente , Conocimientos, Actitudes y Práctica en Salud , Evaluación de Programas y Proyectos de Salud , Beijing
12.
Public Health Nutr ; : 1-23, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39431363

RESUMEN

OBJECTIVE: While many Asian countries undergo dietary transitions, little is known about Japan's dietary pattern changes and their impact on nutritional intake. We aimed to examine 17-year trends in dietary patterns and nutrient intakes in Japan. DESIGN: Principal component analysis was used to derive dietary patterns. The nutrient intake of subjects with principal component scores in the highest quartiles of each dietary pattern was assessed using the NRF9.3 which is a scale that evaluates the entire diet in terms of nutrient density. SETTING: Japan. PARTICIPANTS: We used data from the National Survey 2003-2019 (67,066 women, 55,133 men). RESULTS: Two common dietary patterns were identified in both sexes: the 'Japanese style' and the 'bread and dairy' pattern. Additionally, two other patterns: 'meat and oil' and 'noodles', were pronounced in men. Over the 17 years, the scores of the 'Japanese style' pattern decreased while the 'meat and oil' and the 'bread and dairy' patterns increased. The nutrition assessment result showed that the highest quartiles of the 'Japanese style' pattern had higher NRF scores (women: 716.0, men: 670.5) (p<0.001), whereas those of the 'bread and dairy' pattern had a lower score (636.9 in women, 661.2 in men) (p<0.001). CONCLUSIONS: Trend analysis in this study suggests the ongoing Westernization of diet in Japan. A decreasing trend of the dietary pattern with the most preferable nutrient profile (i.e., the 'Japanese style') might indicate a potential decrease in beneficial nutrient intake and, thus, a deterioration of the nutritional status of the Japanese population.

13.
J Bacteriol ; 205(2): e0035622, 2023 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-36655996

RESUMEN

Widely employed by Gram-negative pathogens for competition and pathogenesis, the type six protein secretion system (T6SS) can inject toxic effectors into neighboring cells through the penetration of a spear-like structure comprising a long Hcp tube and a VgrG-PAAR spike complex. The cone-shaped PAAR is believed to sharpen the T6SS spear for penetration but it remains unclear why PAAR is required for T6SS functions in some bacteria but dispensable in others. Here, we report the conditional requirement of PAAR for T6SS functions in Aeromonas dhakensis, an emerging human pathogen that may cause severe bacteremia. By deleting the two PAAR paralogs, we show that PAAR is not required for T6SS secretion, bacterial killing, or specific effector delivery in A. dhakensis. By constructing combinatorial PAAR and vgrG deletions, we demonstrate that deletion of individual PAAR moderately reduced T6SS functions but double or triple deletions of PAAR in the vgrG deletion mutants severely impaired T6SS functions. Notably, the auxiliary-cluster-encoded PAAR2 and VgrG3 are less critical than the main-cluster-encoded PAAR1 and VgrG1&2 proteins to T6SS functions. In addition, PAAR1 but not PAAR2 contributes to antieukaryotic virulence in amoeba. Our data suggest that, for a multi-PAAR T6SS, the variable role of PAAR paralogs correlates with the VgrG-spike composition that collectively dictates T6SS assembly. IMPORTANCE Gram-negative bacteria often encode multiple paralogs of the cone-shaped PAAR that sits atop the VgrG-spike and is thought to sharpen the spear-like T6SS puncturing device. However, it is unclear why PAAR is required for the assembly of some but not all T6SSs and why there are multiple PAARs if they are not required. Our data delineate a VgrG-mediated conditional requirement for PAAR and suggest a core-auxiliary relationship among different PAAR-VgrG modules that may have been acquired sequentially by the T6SS during evolution.


Asunto(s)
Sistemas de Secreción Tipo VI , Humanos , Sistemas de Secreción Tipo VI/metabolismo , Proteínas Bacterianas/metabolismo , Virulencia
14.
Funct Integr Genomics ; 23(2): 173, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37212877

RESUMEN

Ferroptosis is distinct from classic apoptotic cell death characterized by the accumulation of reactive oxygen species (ROS) and lipid peroxides on the cell membrane. Increasing findings have demonstrated that ferroptosis plays an important role in cancer development, but the exploration of ferroptosis in breast cancer is limited. In our study, we aimed to establish a ferroptosis activation-related model based on the differentially expressed genes between a group exhibiting high ferroptosis activation and a group exhibiting low ferroptosis activation. By using machine learning to establish the model, we verified the accuracy and efficiency of our model in The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) set and gene expression omnibus (GEO) dataset. Additionally, our research innovatively utilized single-cell RNA sequencing data to systematically reveal the microenvironment in the high and low FeAS groups, which demonstrated differences between the two groups from comprehensive aspects, including the activation condition of transcription factors, cell pseudotime features, cell communication, immune infiltration, chemotherapy efficiency, and potential drug resistance. In conclusion, different ferroptosis activation levels play a vital role in influencing the outcome of breast cancer patients and altering the tumor microenvironment in different molecular aspects. By analyzing differences in ferroptosis activation levels, our risk model is characterized by a good prognostic capacity in assessing the outcome of breast cancer patients, and the risk score can be used to prompt clinical treatment to prevent potential drug resistance. By identifying the different tumor microenvironment landscapes between the high- and low-risk groups, our risk model provides molecular insight into ferroptosis in breast cancer patients.


Asunto(s)
Carcinoma , Ferroptosis , Humanos , Ferroptosis/genética , Apoptosis , Fenotipo , Análisis de Secuencia de ARN , Microambiente Tumoral
15.
Small ; 19(31): e2300883, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37029573

RESUMEN

Carbon dots (CDs) with good water solubility and biocompatibility have become a research hotspot in the nano-enzyme and biomedical field. However, the problems of low catalytic activity and ambiguous catalytic site of CDs as nanozymes still need to be addressed. In this work, CDs loaded with Cu single atoms are obtained through pyrolysis, and the coordination structure and surface functional groups are regulated by adjusting the pyrolysis temperature. CDs obtained at 300 °C (named Cu-CDs-300) have the most carboxyl content and Cu is coordinated in the form of CuN2 O2 , which can better decompose H2 O2 to produce free radical and is beneficial to catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB). The vmax is 6.56*10-7  m s-1 , 6.56 times higher than that of horseradish peroxidase (HRP). Moreover, Cu-CDs-300 can effectively lead to CT26 apoptosis by generating much free radicals. This work demonstrates the synergistic effect of oxygen-containing functional groups and metal coordination structures on peroxide-like activity of CDs and provides new ideas for the design of clear active structure and high efficiency peroxide-like single atom CDs catalyst.

16.
Small ; 19(40): e2300584, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37267941

RESUMEN

Electrical stimulation (ES) is a safe and effective procedure in clinical rehabilitation with few adverse effects. However, studies on ES for atherosclerosis (AS) are scarce because ES does not provide a long-term intervention for chronic disease processes. Battery-free implants and surgically mounted them in the abdominal aorta of high-fat-fed Apolipoprotein E (ApoE-/- ) mice are used, which are electrically stimulated for four weeks using a wireless ES device to observe changes in atherosclerotic plaques. Results showed that there is almost no growth of atherosclerotic plaque at the stimulated site in AopE-/- mice after ES. RNA-sequencing (RNA-seq) analysis of Thp-1 macrophages reveal that the transcriptional activity of autophagy-related genes increase substantially after ES. Additionally, ES reduces lipid accumulation in macrophages by restoring ABCA1- and ABCG1-mediated cholesterol efflux. Mechanistically, it is demonstrated that ES reduced lipid accumulation through Sirtuin 1 (Sirt1)/Autophagy related 5 (Atg5) pathway-mediated autophagy. Furthermore, ES reverse autophagic dysfunction in macrophages of AopE-/- mouse plaques by restoring Sirt1, blunting P62 accumulation, and inhibiting the secretion of interleukin (IL)-6, resulting in the alleviation of atherosclerotic lesion formation. Here, a novel approach is shown in which ES can be used as a promising therapeutic strategy for AS treatment through Sirt1/Atg5 pathway-mediated autophagy.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Ratones , Animales , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/patología , Sirtuina 1/genética , Sirtuina 1/uso terapéutico , Colesterol , Aterosclerosis/terapia , Autofagia
17.
PLoS Pathog ; 17(12): e1010116, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34852023

RESUMEN

The type VI secretion system (T6SS) is a spear-like nanomachine found in gram-negative pathogens for delivery of toxic effectors to neighboring bacterial and host cells. Its assembly requires a tip spike complex consisting of a VgrG-trimer, a PAAR protein, and the interacting effectors. However, how the spike controls T6SS assembly remains elusive. Here we investigated the role of three VgrG-effector pairs in Aeromonas dhakensis strain SSU, a clinical isolate with a constitutively active T6SS. By swapping VgrG tail sequences, we demonstrate that the C-terminal ~30 amino-acid tail dictates effector specificity. Double deletion of vgrG1&2 genes (VgrG3+) abolished T6SS secretion, which can be rescued by ectopically expressing chimeric VgrG3 with a VgrG1/2-tail but not the wild type VgrG3. In addition, deletion of effector-specific chaperones also severely impaired T6SS secretion, despite the presence of intact VgrG and effector proteins, in both SSU and Vibrio cholerae V52. We further show that SSU could deliver a V. cholerae effector VasX when expressing a plasmid-borne chimeric VgrG with VasX-specific VgrG tail and chaperone sequences. Pull-down analyses show that two SSU effectors, TseP and TseC, could interact with their cognate VgrGs, the baseplate protein TssK, and the key assembly chaperone TssA. Effectors TseL and VasX could interact with TssF, TssK and TssA in V. cholerae. Collectively, we demonstrate that chimeric VgrG-effector pairs could bypass the requirement of heterologous VgrG complex and propose that effector-stuffing inside the baseplate complex, facilitated by chaperones and the interaction with structural proteins, serves as a crucial structural determinant for T6SS assembly.


Asunto(s)
Aeromonas/metabolismo , Proteínas Bacterianas/metabolismo , Interacciones Huésped-Patógeno/fisiología , Sistemas de Secreción Tipo VI/metabolismo , Vibrio cholerae/metabolismo , Aeromonas/patogenicidad , Vibrio cholerae/patogenicidad
18.
Front Zool ; 20(1): 2, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36635746

RESUMEN

BACKGROUND: Molting is an important physiological process in the growth and development of arthropoda, which is mainly regulated by juvenile hormone and ecdysone. CYP302A1 is a key enzyme which plays a critical role in the synthesis of ecdysone in insects, but it has not been identified in cladocera. RESULTS: The CYP302Al gene of Daphnia sinensis was cloned and its function was analyzed in this paper. The CYP302Al gene of D. sinensis was 5926 bp in full-length, with an open reading frame (ORF) of 1596 bp that encoded 531 amino acids (aa), a molecular weight of 60.82 kDa and an isoelectric point of 9.29. The amino acid sequence analysis revealed that there were five characteristic conserved regions of cytochrome P450 family (namely helix-C, helix-K, helix-I, PERF and heme-binding). In dsRNA mediated experiment, the expression level of CYP302A1 gene decreased significantly (knock-down of 56.22%) in the 5% Escherichia coli concentration treatment. In addition, the expression levels of EcR and USP and HR3 genes in the downstream were also significantly decreased, whereas that of FTZ-f1 gene increased significantly. In the 5% E. coli treatment, the molting time at maturity of D. sinensis prolonged, and the development of embryos in the incubation capsule appeared abnormal or disintegrated. The whole-mount in situ hybridization showed that the CYP302A1 gene of D. sinensis had six expression sites before RNA interference (RNAi), which located in the first antennal ganglion, ovary, cecae, olfactory hair, thoracic limb and tail spine. However, the expression signal of the CYP302A1 gene of D. sinensis disappeared in the first antennal ganglion and obviously attenuated in the ovary after RNAi. CONCLUSION: The CYP302A1 gene played an important role in the ecdysone synthesis pathway of D. sinensis, and the knock-down of the gene affected the molting and reproduction of D. sinensis.

19.
Appl Nurs Res ; 69: 151658, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36635013

RESUMEN

AIM: To measure the knowledge level of research misconduct and explore its associated factors among nurses. BACKGROUND: Engagement in research misconduct by nurses may transfer to professional misconduct in the clinical setting, thereby jeopardizing the quality of patient care. We still know little about the research misconduct situation among nurses. Previous attempts also hardly reflected participants' real knowledge level of research misconduct. METHODS: We applied multistage sampling (province, hospital, and participants) in this cross-sectional survey, and recruited 4112 nurses from 200 tertiary hospitals in 25 provinces. RESULTS: The average knowledge score of the participants was 15.99 ± 5.79. Associated factors of scientific misconduct knowledge score included career situation, educational level, fertility status, research activities index, and perceived consequences for research misconduct. CONCLUSION: It is urgent and necessary to design continuing research integrity training for nurses. Hospital managers and policy-makers should pay more attention to key trainees, including newcomers, nurses from less developed groups and institutions, and those from clinical departments. Training designers should also consider how to help nurses with offspring balance their family and work, and should not neglect the training for nurses with extensive research experience. In addition to conveying knowledge and information, the training can integrate cognitive education of research misconduct to improve the effect.


Asunto(s)
Enfermeras y Enfermeros , Mala Conducta Científica , Humanos , Estudios Transversales , Personal de Salud , China , Centros de Atención Terciaria , Encuestas y Cuestionarios
20.
Small ; 18(38): e2204047, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35997705

RESUMEN

The efficiency of reactive oxygen species (ROS)-mediated cancer therapy is restrained by intrinsic characteristics in the tumor microenvironment (TME), such as overexpressed glutathione (GSH), hypoxia and limited efficiency of H2 O2 . In this work, intelligent copper-dropped calcium carbonate loading sonosensitizer Ce6 nanoparticles (Cu/CaCO3 @Ce6, CCC NPs) are established to realize TME-responsive self-supply of oxygen and successively Ca2+ -overloading-strengthened chemodynamic therapy/sonodynamic therapy (CDT/SDT). CCC NPs release Ca2+ , Cu2+ , and Ce6 in weakly acid and GSH-excessive TME. Released Cu2+ can not only consume GSH and turn into Cu+ via a redox reaction, but also provide CDT-creating hydroxyl radicals through the Fenton-like reaction. Under ultrasound irradiation, the intracellular oxidative stress is amplified profoundly relying on singlet oxygen outburst from SDT. Moreover, Ca2+ influx aggravates the mitochondrial disruption, which further accelerates the oxidation level. The facile and feasible design of the Cu-dropped CaCO3 -based nanoregulators will be further developed as a paradigm in ROS-contributed cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Carbonato de Calcio , Carbonatos , Línea Celular Tumoral , Cobre , Glutatión , Homeostasis , Humanos , Neoplasias/tratamiento farmacológico , Oxígeno , Especies Reactivas de Oxígeno , Oxígeno Singlete , Microambiente Tumoral
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