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1.
Cell ; 177(4): 837-851.e28, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30955886

RESUMEN

L1 retrotransposon-derived sequences comprise approximately 17% of the human genome. Darwinian selective pressures alter L1 genomic distributions during evolution, confounding the ability to determine initial L1 integration preferences. Here, we generated high-confidence datasets of greater than 88,000 engineered L1 insertions in human cell lines that act as proxies for cells that accommodate retrotransposition in vivo. Comparing these insertions to a null model, in which L1 endonuclease activity is the sole determinant dictating L1 integration preferences, demonstrated that L1 insertions are not significantly enriched in genes, transcribed regions, or open chromatin. By comparison, we provide compelling evidence that the L1 endonuclease disproportionately cleaves predominant lagging strand DNA replication templates, while lagging strand 3'-hydroxyl groups may prime endonuclease-independent L1 retrotransposition in a Fanconi anemia cell line. Thus, acquisition of an endonuclease domain, in conjunction with the ability to integrate into replicating DNA, allowed L1 to become an autonomous, interspersed retrotransposon.


Asunto(s)
Elementos de Nucleótido Esparcido Largo/genética , Retroelementos/genética , Línea Celular , Endonucleasas/genética , Endonucleasas/metabolismo , Genoma Humano/genética , Estudio de Asociación del Genoma Completo/métodos , Genómica , Células HeLa , Humanos , Mutagénesis Insercional/genética
2.
Mol Cell ; 75(3): 590-604.e12, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31230816

RESUMEN

Epigenetic silencing defends against LINE-1 (L1) retrotransposition in mammalian cells. However, the mechanisms that repress young L1 families and how L1 escapes to cause somatic genome mosaicism in the brain remain unclear. Here we report that a conserved Yin Yang 1 (YY1) transcription factor binding site mediates L1 promoter DNA methylation in pluripotent and differentiated cells. By analyzing 24 hippocampal neurons with three distinct single-cell genomic approaches, we characterized and validated a somatic L1 insertion bearing a 3' transduction. The source (donor) L1 for this insertion was slightly 5' truncated, lacked the YY1 binding site, and was highly mobile when tested in vitro. Locus-specific bisulfite sequencing revealed that the donor L1 and other young L1s with mutated YY1 binding sites were hypomethylated in embryonic stem cells, during neurodifferentiation, and in liver and brain tissue. These results explain how L1 can evade repression and retrotranspose in the human body.


Asunto(s)
Represión Epigenética/genética , Elementos de Nucleótido Esparcido Largo/genética , Retroelementos/genética , Factor de Transcripción YY1/genética , Sitios de Unión/genética , Metilación de ADN/genética , Proteínas de Unión al ADN/genética , Genoma Humano/genética , Hipocampo/metabolismo , Humanos , Hígado/metabolismo , Neuronas/metabolismo , Análisis de la Célula Individual
3.
Nucleic Acids Res ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850156

RESUMEN

Alu elements are non-autonomous Short INterspersed Elements (SINEs) derived from the 7SL RNA gene that are present at over one million copies in human genomic DNA. Alu mobilizes by a mechanism known as retrotransposition, which requires the Long INterspersed Element-1 (LINE-1) ORF2-encoded protein (ORF2p). Here, we demonstrate that HeLa strains differ in their capacity to support Alu retrotransposition. Human Alu elements retrotranspose efficiently in HeLa-HA and HeLa-CCL2 (Alu-permissive) strains, but not in HeLa-JVM or HeLa-H1 (Alu-nonpermissive) strains. A similar pattern of retrotransposition was observed for other 7SL RNA-derived SINEs and tRNA-derived SINEs. In contrast, mammalian LINE-1s, a zebrafish LINE, a human SINE-VNTR-Alu (SVA) element, and an L1 ORF1-containing mRNA can retrotranspose in all four HeLa strains. Using an in vitro reverse transcriptase-based assay, we show that Alu RNAs associate with ORF2p and are converted into cDNAs in both Alu-permissive and Alu-nonpermissive HeLa strains, suggesting that 7SL- and tRNA-derived SINEs use strategies to 'hijack' L1 ORF2p that are distinct from those used by SVA elements and ORF1-containing mRNAs. These data further suggest ORF2p associates with the Alu RNA poly(A) tract in both Alu-permissive and Alu-nonpermissive HeLa strains, but that Alu retrotransposition is blocked after this critical step in Alu-nonpermissive HeLa strains.

4.
PLoS Genet ; 19(7): e1010795, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37405998

RESUMEN

Retrotransposons have generated about half of the human genome and LINE-1s (L1s) are the only autonomously active retrotransposons. The cell has evolved an arsenal of defense mechanisms to protect against retrotransposition with factors we are only beginning to understand. In this study, we investigate Zinc Finger CCHC-Type Containing 3 (ZCCHC3), a gag-like zinc knuckle protein recently reported to function in the innate immune response to infecting viruses. We show that ZCCHC3 also severely restricts human retrotransposons and associates with the L1 ORF1p ribonucleoprotein particle. We identify ZCCHC3 as a bona fide stress granule protein, and its association with LINE-1 is further supported by colocalization with L1 ORF1 protein in stress granules, dense cytoplasmic aggregations of proteins and RNAs that contain stalled translation pre-initiation complexes and form when the cell is under stress. Our work also draws links between ZCCHC3 and the anti-viral and retrotransposon restriction factors Mov10 RISC Complex RNA Helicase (MOV10) and Zinc Finger CCCH-Type, Antiviral 1 (ZC3HAV1, also called ZAP). Furthermore, collective evidence from subcellular localization, co-immunoprecipitation, and velocity gradient centrifugation connects ZCCHC3 with the RNA exosome, a multi-subunit ribonuclease complex capable of degrading various species of RNA molecules and that has previously been linked with retrotransposon control.


Asunto(s)
Retroelementos , Gránulos de Estrés , Humanos , Retroelementos/genética , Proteínas de Choque Térmico/genética , Zinc , Elementos de Nucleótido Esparcido Largo/genética , ARN Helicasas/genética , ARN Helicasas/metabolismo
5.
Hum Mol Genet ; 32(16): 2646-2655, 2023 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-37369012

RESUMEN

Animal studies implicate one-carbon metabolism and DNA methylation genes in hepatocellular carcinoma (HCC) development in the setting of metabolic perturbations. Using human samples, we investigated the associations between common and rare variants in these closely related biochemical pathways and risk for metabolic HCC development in a multicenter international study. We performed targeted exome sequencing of 64 genes among 556 metabolic HCC cases and 643 cancer-free controls with metabolic conditions. Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for multiple comparisons. Gene-burden tests were used for rare variant associations. Analyses were performed in the overall sample and among non-Hispanic whites. The results show that among non-Hispanic whites, presence of rare functional variants in ABCC2 was associated with 7-fold higher risk of metabolic HCC (OR = 6.92, 95% CI: 2.38-20.15, P = 0.0004), and this association remained significant when analyses were restricted to functional rare variants observed in ≥2 participants (cases 3.2% versus controls 0.0%, P = 1.02 × 10-5). In the overall multiethnic sample, presence of rare functional variants in ABCC2 was nominally associated with metabolic HCC (OR = 3.60, 95% CI: 1.52-8.58, P = 0.004), with similar nominal association when analyses were restricted to functional rare variants observed in ≥2 participants (cases 2.9% versus controls 0.2%, P = 0.006). A common variant in PNPLA3 (rs738409[G]) was associated with higher HCC risk in the overall sample (P = 6.36 × 10-6) and in non-Hispanic whites (P = 0.0002). Our findings indicate that rare functional variants in ABCC2 are associated with susceptibility to metabolic HCC in non-Hispanic whites. PNPLA3-rs738409 is also associated with metabolic HCC risk.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Metilación de ADN/genética , Predisposición Genética a la Enfermedad , Estudios de Casos y Controles , Células Germinativas/patología , Carbono , Polimorfismo de Nucleótido Simple/genética
6.
Plant Physiol ; 195(1): 343-355, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38270530

RESUMEN

Flowering plants contain tightly controlled pollen-pistil interactions required for promoting intraspecific fertilization and preventing interspecific hybridizations. In Arabidopsis (Arabidopsis thaliana), several receptor kinases (RKs) are known to regulate the later stages of intraspecific pollen tube growth and ovular reception in the pistil, but less is known about RK regulation of the earlier stages. The Arabidopsis RECEPTOR-LIKE KINASE IN FLOWERS1 (RKF1)/RKF1-LIKE (RKFL) 1-3 cluster of 4 leucine-rich repeat malectin (LRR-MAL) RKs was previously found to function in the stigma to promote intraspecific pollen hydration. In this study, we tested additional combinations of up to 7 Arabidopsis LRR-MAL RK knockout mutants, including RKF1, RKFL1-3, LysM RLK1-INTERACTING KINASE1, REMORIN-INTERACTING RECEPTOR1, and NEMATODE-INDUCED LRR-RLK2. These LRR-MAL RKs were discovered to function in the female stigma to support intraspecific Arabidopsis pollen tube growth and to establish a prezygotic interspecific barrier against Capsella rubella pollen. Thus, this study uncovered additional biological functions for this poorly understood group of RKs in regulating the early stages of Arabidopsis sexual reproduction.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Flores , Tubo Polínico , Polen , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Flores/genética , Flores/fisiología , Polen/genética , Polen/fisiología , Polen/crecimiento & desarrollo , Tubo Polínico/genética , Tubo Polínico/crecimiento & desarrollo , Polinización/fisiología , Capsella/genética , Capsella/fisiología , Capsella/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas Quinasas/metabolismo , Proteínas Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Repetidas Ricas en Leucina
7.
Mol Cell Proteomics ; 22(7): 100590, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37301378

RESUMEN

Ovarian cancer, a leading cause of cancer-related deaths among women, has been notoriously difficult to screen for and diagnose early, as early detection significantly improves survival. Researchers and clinicians seek routinely usable and noninvasive screening methods; however, available methods (i.e., biomarker screening) lack desirable sensitivity/specificity. The most fatal form, high-grade serous ovarian cancer, often originate in the fallopian tube; therefore, sampling from the vaginal environment provides more proximal sources for tumor detection. To address these shortcomings and leverage proximal sampling, we developed an untargeted mass spectrometry microprotein profiling method and identified cystatin A, which was validated in an animal model. To overcome the limits of detection inherent to mass spectrometry, we demonstrated that cystatin A is present at 100 pM concentrations using a label-free microtoroid resonator and translated our workflow to patient-derived clinical samples, highlighting the potential utility of early stage detection where biomarker levels would be low.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Ováricas , Humanos , Animales , Femenino , Cistatina A , Neoplasias Ováricas/metabolismo , Micropéptidos
8.
Gut ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38754953

RESUMEN

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) has limited therapeutic options, particularly with immune checkpoint inhibitors. Highly chemoresistant 'stem-like' cells, known as cancer stem cells (CSCs), are implicated in PDAC aggressiveness. Thus, comprehending how this subset of cells evades the immune system is crucial for advancing novel therapies. DESIGN: We used the KPC mouse model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre) and primary tumour cell lines to investigate putative CSC populations. Transcriptomic analyses were conducted to pinpoint new genes involved in immune evasion. Overexpressing and knockout cell lines were established with lentiviral vectors. Subsequent in vitro coculture assays, in vivo mouse and zebrafish tumorigenesis studies, and in silico database approaches were performed. RESULTS: Using the KPC mouse model, we functionally confirmed a population of cells marked by EpCAM, Sca-1 and CD133 as authentic CSCs and investigated their transcriptional profile. Immune evasion signatures/genes, notably the gene peptidoglycan recognition protein 1 (PGLYRP1), were significantly overexpressed in these CSCs. Modulating PGLYRP1 impacted CSC immune evasion, affecting their resistance to macrophage-mediated and T-cell-mediated killing and their tumourigenesis in immunocompetent mice. Mechanistically, tumour necrosis factor alpha (TNFα)-regulated PGLYRP1 expression interferes with the immune tumour microenvironment (TME) landscape, promoting myeloid cell-derived immunosuppression and activated T-cell death. Importantly, these findings were not only replicated in human models, but clinically, secreted PGLYRP1 levels were significantly elevated in patients with PDAC. CONCLUSIONS: This study establishes PGLYRP1 as a novel CSC-associated marker crucial for immune evasion, particularly against macrophage phagocytosis and T-cell killing, presenting it as a promising target for PDAC immunotherapy.

9.
Anal Chem ; 96(21): 8308-8316, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38752543

RESUMEN

Microbial biofilms represent an important lifestyle for bacteria and are dynamic three-dimensional structures. Cyclic dimeric guanosine monophosphate (c-di-GMP) is a ubiquitous signaling molecule that is known to be tightly regulated with biofilm processes. While measurements of global levels of c-di-GMP have proven valuable toward understanding the genetic control of c-di-GMP production, there is a need for tools to observe the local changes of c-di-GMP production in biofilm processes. We have developed a label-free method for the direct detection of c-di-GMP in microbial colony biofilms using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). We applied this method to the enteric pathogen Vibrio cholerae, the marine symbiont V. fischeri, and the opportunistic pathogen Pseudomonas aeruginosa PA14 and detected spatial and temporal changes in c-di-GMP signal that accompanied genetic alterations in factors that synthesize and degrade the compound. We further demonstrated how this method can be simultaneously applied to detect additional metabolites of interest from a single sample.


Asunto(s)
Biopelículas , GMP Cíclico , Pseudomonas aeruginosa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Vibrio cholerae , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , GMP Cíclico/análisis , Pseudomonas aeruginosa/metabolismo , Vibrio cholerae/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Aliivibrio fischeri/metabolismo
10.
Mass Spectrom Rev ; 2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37597182

RESUMEN

Epigenetic modifications are closely related to certain disorders of the organism, including the development of tumors. One of the main epigenetic modifications is the methylation of DNA cytosines, 5-methyl-2'-deoxycycytidine. Furthermore, 5-mdC can be oxidized to form three new modifications, 5-(hydroxymethyl)-2'-deoxycytidine, 5-formyl-2'-deoxycytidine, and 5-carboxy-2'-deoxycytidine. The coupling of liquid chromatography with tandem mass spectrometry has been widely used for the total determination of methylated DNA cytosines in samples of biological and clinical interest. These methods are based on the measurement of the free compounds (e.g., urine) or after complete hydrolysis of the DNA (e.g., tissues) followed by a preconcentration, derivatization, and/or clean-up step. This review highlights the main advances in the quantification of modified nucleotides and nucleosides by isotope dilution using isotopically labeled analogs combined with liquid or gas chromatography coupled to mass spectrometry reported in the last 20 years. The different possible sources of labeled compounds are indicated. Special emphasis has been placed on the different types of chromatography commonly used (reverse phase and hydrophilic interaction liquid chromatography) and the derivatization methods developed to enhance chromatographic resolution and ionization efficiency. We have also revised the application of bidimensional chromatography and indicated significant biological and clinical applications of these determinations.

11.
Hepatology ; 78(3): 709-726, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36999529

RESUMEN

BACKGROUND AND AIMS: Cholestasis is characterized by intrahepatic accumulation of bile constituents, including bile acids (BAs), which promote liver damage. The apical sodium-dependent BA transporter (ASBT) plays an important role in BA reabsorption and signaling in ileum, bile ducts, and kidneys. Our aim was to investigate the pharmacokinetics and pharmacological activity of A3907, an oral and systemically available ASBT inhibitor in experimental mouse models of cholestasis. In addition, the tolerability, pharmacokinetics, and pharmacodynamics of A3907 were examined in healthy humans. APPROACH AND RESULTS: A3907 was a potent and selective ASBT inhibitor in vitro. In rodents, orally administered A3907 distributed to the ASBT-expressing organs, that is, ileum, liver, and kidneys, and dose dependently increased fecal BA excretion. A3907 improved biochemical, histological, and molecular markers of liver and bile duct injury in Mdr2-/- mice and also had direct protective effects on rat cholangiocytes exposed to cytotoxic BA concentrations in vitro . In bile duct ligated mice, A3907 increased urinary BA elimination, reduced serum BA levels, and prevented body weight loss, while improving markers of liver injury. A3907 was well tolerated and demonstrated target engagement in healthy volunteers. Plasma exposure of A3907 in humans was within the range of systemic concentrations that achieved therapeutic efficacy in mouse. CONCLUSIONS: The systemic ASBT inhibitor A3907 improved experimental cholestatic disease by targeting ASBT function at the intestinal, liver, and kidney levels, resulting in marked clearance of circulating BAs and liver protection. A3907 is well tolerated in humans, supporting further clinical development for the treatment of cholestatic liver diseases.


Asunto(s)
Colestasis , Simportadores , Humanos , Ratones , Animales , Ratas , Colestasis/tratamiento farmacológico , Hígado , Conductos Biliares , Bilis , Ácidos y Sales Biliares/uso terapéutico , Proteínas de Transporte de Membrana , Transportadores de Anión Orgánico Sodio-Dependiente
12.
Ann Surg Oncol ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896226

RESUMEN

BACKGROUND: Resection of perihilar cholangiocarcinoma (pCCA) is a complex procedure with a high risk of postoperative mortality and early disease recurrence. The objective of this study was to compare patient characteristics and overall survival (OS) between pCCA patients who underwent an R1 resection and patients with localized pCCA who received palliative systemic chemotherapy. METHODS: Patients with a diagnosis of pCCA between 1997-2021 were identified from the European Network for the Study of Cholangiocarcinoma (ENS-CCA) registry. pCCA patients who underwent an R1 resection were compared with patients with localized pCCA (i.e., nonmetastatic) who were ineligible for surgical resection and received palliative systemic chemotherapy. The primary outcome was OS. RESULTS: Overall, 146 patients in the R1 resection group and 92 patients in the palliative chemotherapy group were included. The palliative chemotherapy group more often underwent biliary drainage (95% vs. 66%, p < 0.001) and had more vascular encasement on imaging (70% vs. 49%, p = 0.012) and CA 19.9 was more frequently >200 IU/L (64 vs. 45%, p = 0.046). Median OS was comparable between both groups (17.1 vs. 16 months, p = 0.06). Overall survival at 5 years after diagnosis was 20.0% with R1 resection and 2.2% with chemotherapy. Type of treatment (i.e., R1 resection or palliative chemotherapy) was not an independent predictor of OS (hazard ratio 0.76, 95% confidence interval 0.55-1.07). CONCLUSIONS: Palliative systemic chemotherapy should be considered instead of resection in patients with a high risk of both R1 resection and postoperative mortality.

13.
Med Vet Entomol ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39011849

RESUMEN

Several species of ectoparasites, including chewing lice and mites are closely associated with their hosts. The Andean condor (Vultur gryphus) is globally listed as vulnerable by the IUCN and its population has been steadily declining in recent decades suggesting a potential extinction of associated entomofauna. The purpose of this study was to record the species of ectoparasites infesting three individuals of Andean condor found dead in the 'Páramo del Almorzadero' Santander Department, Northeastern Colombia. One juvenile (male) and two adults (male and female) Andean condors received for necropsy were carefully examined for ectoparasite infestation. Specimens were collected and preserved in ethanol (70%) for taxonomic studies. Morphologic identification and morphometric records were made under light microscopy. Some specimens were also prepared for scanning electron microscopy and others were subjected to DNA extraction to amplify and obtain sequences of the cytochrome-C oxidase subunit I (COI) gene for phylogenetic analyses. Lice were collected from the juvenile condor and the adult female and identified as Falcolipeurus assesor (Phthiraptera: Ischnocera) in the juvenile condor (8 females, 19 males and 8 nymphs) and the adult (1 female); Colpocephalum trichosum (Phthiraptera: Amblycera) in the juvenile (19 females, 24 males and 1 nymph) and the adult (2 females, 2 males and 3 nymphs); and Cuculiphilus zonatus (Phthiraptera: Amblycera) in the juvenile (40 females, 43 males and 15 nymphs) and the adult (1 male and 2 nymphs). Moreover, one mite collected from the juvenile condor was identified as Ancyralges cathartinus (Acari: Astigmata) (1 female). Morphometric data was obtained for the adult stages of F. assesor (6 females and 13 males), C. trichosum (9 females and 9 males) and C. zonatus (10 females and 10 males). We obtained the first DNA sequences of COI for F. assessor, and C. trichosum, where phylogenetic tree analysis showed that F. assessor is more closely related to Falcolipeurus marginalis, and C. trichosum to Colpocephalum kelloggi. This represents the first record of parasites in Andean condor from Colombia and contributes to the knowledge of chewing lice and mites associated with an endemic and endangered bird species. Further studies on Andean condor ectoparasites should be focused on documenting host-parasite interactions and potential health impacts in these wild birds.


Varias especies de ectoparásitos, incluidos piojos masticadores y ácaros están estrechamente asociados a sus hospedadores. El cóndor andino (Vultur gryphus) está catalogado por la UICN como una especie vulnerable y su población ha ido disminuyendo constantemente en las últimas décadas, lo que sugiere una posible extinción de la entomofauna asociada. El propósito de este estudio fue registrar las especies de ectoparásitos infestando a tres individuos de cóndor andino encontrados muertos en el Páramo del Almorzadero, Departamento de Santander, Noreste de Colombia. Un cóndor andino juvenil (macho) y dos adultos (macho y hembra) recibidos para necropsia fueron examinados cuidadosamente para detectar infestación por ectoparásitos. Los especímenes fueron recolectados y preservados en etanol (70%) para estudios taxonómicos. La identificación morfológica y los registros morfométricos se ejecutaron bajo microscopía óptica. Algunas muestras también se prepararon para microscopía electrónica de barrido y otras se sometieron a extracción de ADN para amplificar y obtener secuencias del gen de la subunidad I (COI) del citocromo­C oxidasa para análisis filogenéticos. Los piojos recolectados del cóndor juvenil y de la hembra adulta se identificaron como Falcolipeurus assesor (Phthiraptera: Ischnocera) en el cóndor juvenil (8 hembras, 19 machos y 8 ninfas) y en el adulto (1 hembra); Colpocephalum trichosum (Phthiraptera: Amblycera) en el juvenil (19 hembras, 24 machos y 1 ninfa) y en el adulto (2 hembras, 2 machos y 3 ninfas); y Cuculiphilus zonatus (Phthiraptera: Amblycera) en el juvenil (40 hembras, 43 machos y 15 ninfas) y en el adulto (1 macho y 2 ninfas). Además, un ácaro recolectado del cóndor juvenil fue identificado como Ancyralges cathartinus (Acari: Astigmata) (1 hembra). Se obtuvieron datos morfométricos para los estadios adultos de F. assesor (6 hembras y 13 machos), C. trichosum (9 hembras y 9 machos) y C. zonatus (10 hembras y 10 machos). Secuencias de ADN basadas en COI para las especies F. assesor y C. trichosum son reportadas por la primera vez, donde el análisis filogenetico mostró que F. assesor está más estrechamente relacionado con Falcolipeurus marginalis y C. trichosum con Colpocephalum kelloggi. Este representa el primer registro de parásitos en cóndor andino de Colombia y contribuye al conocimiento de los piojos masticadores y ácaros asociados a una especie de ave endémica de los Andes y en peligro de extinción. Otros estudios sobre los ectoparásitos del cóndor andino deberían centrarse en documentar las interacciones hospedador­parásito y los posibles impactos en la salud de estas aves silvestres.

14.
Graefes Arch Clin Exp Ophthalmol ; 262(5): 1443-1453, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38197992

RESUMEN

PURPOSE: The main purpose of this study was to perform an immunohistochemical, functional, and anatomical evaluation of patients with idiopathic epiretinal membrane (ERM). METHODS: Twenty-four specimens of idiopathic ERM from 24 consecutive patients who underwent 23 G pars plana vitrectomy for ERM and internal limiting membrane (ILM) peeling at the San Juan University Hospital in Alicante (Spain) in 2019 were analyzed. All patients underwent a complete ophthalmological examination including measurement of best corrected visual acuity (BCVA) and macular analysis by spectral-domain optical coherence tomography (SD-OCT) at the time of diagnosis and 3 months after surgery. Specific glial fibrillar acid protein antibodies (GFAP) and S100 calcium-binding protein ß (S100ß) immunostaining markers were used to identify the macroglial component of the ERM, Müller cells, and astrocytes. Ionized calcium-binding adapter molecule 1 protein (Iba1) antibodies were used as specific markers for inflammatory cells, such as microglia and macrophages. RESULTS: Mean preoperative BCVA measured with Snellen chart was 0.3 and 0.6 preoperatively and at 3 months after surgery, respectively. SD-OCT identified 15 patients (62.5%) with a disruption of the outer retinal hyperreflective bands. The immunohistochemical study showed the presence of Müller cells in almost all cases (91.6%), as well of abundant microglia and macrophages. Microglia and macrophages were more frequently present in earlier stages of ERM. Microglia were present in ERM independently of the outer retinal hyperreflective bands integrity as measured by SD-OCT. A greater presence of macrophages was found in those ERMs with no outer retinal hyperreflective band disruption. CONCLUSIONS: Müller cells seem to be the most frequent cell group in ERMs, with also presence of microglia cells and macrophages. Astrocytes were more frequently found in early stages of ERMs. Microglia and macrophages were most frequent in ERMs with early stage (1, 2, or 3) than in advanced stages (4).


Asunto(s)
Membrana Epirretinal , Humanos , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/cirugía , Retina , Vitrectomía/métodos , Membrana Basal/cirugía , Tomografía de Coherencia Óptica/métodos , Estudios Retrospectivos
15.
BMC Public Health ; 24(1): 404, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326802

RESUMEN

BACKGROUND: To inform the development of an online tool to be potentially used in shared decision-making about breast cancer screening, French women were questioned about participation in breast cancer screening, the health professional's role, and their perceptions of the proposed tool. METHODS: We organised focus group discussions with 55 French women. Two different strategies were used to recruit women from high and low socioeconomic backgrounds. We applied both inductive and deductive approaches to conduct a thematic analysis of the discussions. We analysed the responses by using the main determinants from different health behaviour models and compared the two groups. RESULTS: Independently of socioeconomic status, the most important determinant for a woman's participation in breast cancer screening was the perceived severity of breast cancer and the perceived benefits of its early detection by screening. Cues to action reported by both groups were invitation letters; recommendations by health professionals, or group/community activities and public events were reported by women from high and low socioeconomic backgrounds, respectively. Among other positive determinants, women from high socioeconomic backgrounds reported making informed decisions and receiving peer support whereas women from low socioeconomic backgrounds reported community empowerment through group/community events. Fear of cancer was reported as a barrier in both groups. Among other barriers, language issues were reported only by women from low socioeconomic backgrounds; women from high socioeconomic backgrounds reported breast cancer screening-related risks other than overdiagnosis and/or overtreatment. Barriers to accessing the online tool to be developed were mainly reported by women from high socioeconomic backgrounds. CONCLUSION: Limitations in implementing shared decision-making for women from low socioeconomic backgrounds were highlighted. An online tool that is suitable for all women, regardless of socioeconomic status, would provide "on-demand" reliable and tailored information about breast cancer screening and improve access to health professionals and social exchanges.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/prevención & control , Grupos Focales , Detección Precoz del Cáncer , Investigación Cualitativa , Clase Social , Toma de Decisiones , Tamizaje Masivo
16.
Parasitol Res ; 123(6): 255, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38922514

RESUMEN

Hyperparasitism is defined as the interaction where one parasite is infected by another parasite. In bat flies (Streblidae and Nycteribiidae), both hyperparasites and microparasites (bacteria, viruses, fungi, and arthropods such as mites) have been documented. Fungi belonging to the order Laboulbeniales are microscopic parasites of a wide diversity of arthropod hosts. Three genera exclusively target bat flies: Arthrorhynchus, which parasitizes species within Nycteribiidae in the Eastern Hemisphere, while genus Gloeandromyces and Nycteromyces parasitize Streblidae in the Western Hemisphere. Among the hyperparasitic arthropods, mites of family Neothrombidiidae, particularly the monospecific genus Monunguis, are known to parasitize bat flies. Here we present the first records of the hyperparasites Monunguis streblida and Gloeandromyces pageanus f. polymorphus parasitizing Streblidae bat flies in Colombia and a summary of these hyperparasitic interactions in the Neotropics. We detected fungi and mites parasitizing bat flies that were collected in the Magdalena River Basin, Colombia, in field expeditions in 2018, 2022, and 2023. We identified 17 bat flies and two species of hyperparasites, specifically M. streblida and the fungi Gloeandromyces. Our search for reports of these interactions in the Neotropics revealed that seven species of Trichobius (Streblidae) are parasitized by M. streblida, whereas Paratrichobius longicrus (Streblidae) is parasitized by Gloeandromyces pageanus f. polymorphus. These interactions have been reported in 11 countries, but our records are the first of M. streblida and Laboulbeniales fungi parasitizing bat flies in Colombia. So far, a total of 14 species of fungi and one species of mite have been associated with 19 species of bat flies, which in turn, are linked to 15 species of Neotropical bats.


Asunto(s)
Quirópteros , Dípteros , Animales , Dípteros/microbiología , Dípteros/parasitología , Quirópteros/parasitología , Colombia , Ácaros/microbiología , Ácaros/fisiología , Interacciones Huésped-Parásitos
17.
J Hepatol ; 79(1): 93-108, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36868481

RESUMEN

BACKGROUND & AIMS: Cholangiocarcinoma (CCA), heterogeneous biliary tumours with dismal prognosis, lacks accurate early diagnostic methods especially important for individuals at high-risk (i.e. those with primary sclerosing cholangitis [PSC]). Here, we searched for protein biomarkers in serum extracellular vesicles (EVs). METHODS: EVs from patients with isolated PSC (n = 45), concomitant PSC-CCA (n = 44), PSC who developed CCA during follow-up (PSC to CCA; n = 25), CCAs from non-PSC aetiology (n = 56), and hepatocellular carcinoma (n = 34) and healthy individuals (n = 56) were characterised by mass spectrometry. Diagnostic biomarkers for PSC-CCA, non-PSC CCA, or CCAs regardless of aetiology (Pan-CCAs) were defined and validated by ELISA. Their expression was evaluated in CCA tumours at a single-cell level. Prognostic EV biomarkers for CCA were investigated. RESULTS: High-throughput proteomics of EVs identified diagnostic biomarkers for PSC-CCA, non-PSC CCA, or Pan-CCA, and for the differential diagnosis of intrahepatic CCA and hepatocellular carcinoma, which were cross-validated by ELISA using total serum. Machine learning-based algorithms disclosed CRP/FIBRINOGEN/FRIL for the diagnosis of PSC-CCA (local disease [LD]) vs. isolated PSC (AUC = 0.947; odds ratio [OR] =36.9) and, combined with carbohydrate antigen 19-9, overpowers carbohydrate antigen 19-9 alone. CRP/PIGR/VWF allowed the diagnosis of LD non-PSC CCAs vs. healthy individuals (AUC = 0.992; OR = 387.5). It is noteworthy that CRP/FRIL accurately diagnosed LD Pan-CCA (AUC = 0.941; OR = 89.4). Levels of CRP/FIBRINOGEN/FRIL/PIGR showed predictive capacity for CCA development in PSC before clinical evidence of malignancy. Multi-organ transcriptomic analysis revealed that serum EV biomarkers were mostly expressed in hepatobiliary tissues, and single-cell RNA sequencing and immunofluorescence analysis of CCA tumours showed their presence mainly in malignant cholangiocytes. Multivariable analysis unveiled EV prognostic biomarkers, with COMP/GNAI2/CFAI and ACTN1/MYCT1/PF4V associated negatively and positively with patients' survival, respectively. CONCLUSIONS: Serum EVs contain protein biomarkers for the prediction, early diagnosis, and prognostication of CCA that are detectable using total serum, representing a tumour cell-derived liquid biopsy tool for personalised medicine. IMPACT AND IMPLICATIONS: The accuracy of current imaging tests and circulating tumour biomarkers for cholangiocarcinoma (CCA) diagnosis is far from satisfactory. Most CCAs are considered sporadic, although up to 20% of patients with primary sclerosing cholangitis (PSC) develop CCA during their lifetime, constituting a major cause of PSC-related death. This international study has proposed protein-based and aetiology-related logistic models with predictive, diagnostic, or prognostic capacities by combining two to four circulating protein biomarkers, moving a step forward into personalised medicine. These novel liquid biopsy tools may allow the (i) easy and non-invasive diagnosis of sporadic CCAs, (ii) identification of patients with PSC with higher risk for CCA development, (iii) establishment of cost-effective surveillance programmes for the early detection of CCA in high-risk populations (e.g. PSC), and (iv) prognostic stratification of patients with CCA, which, altogether, may increase the number of cases eligible for potentially curative options or to receive more successful treatments, decreasing CCA-related mortality.


Asunto(s)
Neoplasias de los Conductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Colangitis Esclerosante , Neoplasias Hepáticas , Humanos , Colangitis Esclerosante/complicaciones , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/complicaciones , Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/etiología , Colangiocarcinoma/metabolismo , Biomarcadores de Tumor , Diagnóstico Precoz , Biopsia Líquida , Conductos Biliares Intrahepáticos/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/complicaciones , Carbohidratos , Proteínas Nucleares
18.
Anal Chem ; 95(46): 16775-16785, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37934885

RESUMEN

As genetic tools continue to emerge and mature, more information is revealed about the identity and diversity of microbial community members. Genetic tools can also be used to make predictions about the chemistry that bacteria and fungi produce to function and communicate with one another and the host. Ongoing efforts to identify these products and link genetic information to microbiome chemistry rely on analytical tools. This tutorial highlights recent advancements in microbiome studies driven by techniques in mass spectrometry.


Asunto(s)
Microbiota , Microbiota/genética , Hongos , Bacterias/genética , Espectrometría de Masas
19.
Bioinformatics ; 38(16): 4046-4047, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35758608

RESUMEN

MOTIVATION: Advances in mass spectrometry have led to the development of mass spectrometers with ion mobility spectrometry capabilities and dual-source instrumentation; however, the current software ecosystem lacks interoperability with downstream data analysis using open-source software and pipelines. RESULTS: Here, we present TIMSCONVERT, a data conversion high-throughput workflow from timsTOF Pro/fleX mass spectrometer raw data files to mzML and imzML formats that incorporates ion mobility data while maintaining compatibility with data analysis tools. We showcase several examples using data acquired across different experiments and acquisition modalities on the timsTOF fleX MS. AVAILABILITY AND IMPLEMENTATION: TIMSCONVERT and its documentation can be found at https://github.com/gtluu/timsconvert and is available as a standalone command-line interface tool for Windows and Linux, NextFlow workflow and online in the Global Natural Products Social (GNPS) platform. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Ecosistema , Programas Informáticos , Flujo de Trabajo , Espectrometría de Masas/métodos , Análisis de Datos
20.
Hepatology ; 76(4): 1121-1134, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35220605

RESUMEN

BACKGROUND AND AIMS: We previously identified subsets of patients with NAFLD with different metabolic phenotypes. Here we align metabolomic signatures with cardiovascular disease (CVD) and genetic risk factors. APPROACH AND RESULTS: We analyzed serum metabolome from 1154 individuals with biopsy-proven NAFLD, and from four mouse models of NAFLD with impaired VLDL-triglyceride (TG) secretion, and one with normal VLDL-TG secretion. We identified three metabolic subtypes: A (47%), B (27%), and C (26%). Subtype A phenocopied the metabolome of mice with impaired VLDL-TG secretion; subtype C phenocopied the metabolome of mice with normal VLDL-TG; and subtype B showed an intermediate signature. The percent of patients with NASH and fibrosis was comparable among subtypes, although subtypes B and C exhibited higher liver enzymes. Serum VLDL-TG levels and secretion rate were lower among subtype A compared with subtypes B and C. Subtype A VLDL-TG and VLDL-apolipoprotein B concentrations were independent of steatosis, whereas subtypes B and C showed an association with these parameters. Serum TG, cholesterol, VLDL, small dense LDL5,6 , and remnant lipoprotein cholesterol were lower among subtype A compared with subtypes B and C. The 10-year high risk of CVD, measured with the Framingham risk score, and the frequency of patatin-like phospholipase domain-containing protein 3 NAFLD risk allele were lower in subtype A. CONCLUSIONS: Metabolomic signatures identify three NAFLD subgroups, independent of histological disease severity. These signatures align with known CVD and genetic risk factors, with subtype A exhibiting a lower CVD risk profile. This may account for the variation in hepatic versus cardiovascular outcomes, offering clinically relevant risk stratification.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad del Hígado Graso no Alcohólico , Animales , Apolipoproteínas B , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , VLDL-Colesterol/metabolismo , Factores de Riesgo de Enfermedad Cardiaca , Lipoproteínas VLDL , Hígado/patología , Ratones , Enfermedad del Hígado Graso no Alcohólico/patología , Fosfolipasas/metabolismo , Factores de Riesgo , Triglicéridos/metabolismo
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