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1.
Antimicrob Agents Chemother ; : e0079324, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39254294

RESUMEN

Plasmodium parasite resistance to antimalarial drugs is a serious threat to public health in malaria-endemic areas. Compounds that target core cellular processes like translation are highly desirable, as they should be capable of killing parasites in their liver and blood stage forms, regardless of molecular target or mechanism. Assays that can identify these compounds are thus needed. Recently, specific quantification of native Plasmodium berghei liver stage protein synthesis, as well as that of the hepatoma cells supporting parasite growth, was achieved via automated confocal feedback microscopy of the o-propargyl puromycin (OPP)-labeled nascent proteome, but this imaging modality is limited in throughput. Here, we developed and validated a miniaturized high content imaging (HCI) version of the OPP assay that increases throughput, before deploying this approach to screen the Pathogen Box. We identified only two hits; both of which are parasite-specific quinoline-4-carboxamides, and analogs of the clinical candidate and known inhibitor of blood and liver stage protein synthesis, DDD107498/cabamiquine. We further show that these compounds have strikingly distinct relationships between their antiplasmodial and translation inhibition efficacies. These results demonstrate the utility and reliability of the P. berghei liver stage OPP HCI assay for the specific, single-well quantification of Plasmodium and human protein synthesis in the native cellular context, allowing the identification of selective Plasmodium translation inhibitors with the highest potential for multistage activity.

2.
PLoS Pathog ; 18(7): e1010311, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35834586

RESUMEN

RNA splicing plays an essential role in the expression of eukaryotic genes. We previously showed that KSHV ORF57 is a viral splicing factor promoting viral lytic gene expression. In this report, we compared the splicing profile of viral RNAs in BCBL-1 cells carrying a wild-type (WT) versus the cells containing an ORF57 knock-out (57KO) KSHV genome during viral lytic infection. Our analyses of viral RNA splice junctions from RNA-seq identified 269 RNA splicing events in the WT and 255 in the 57KO genome, including the splicing events spanning large parts of the viral genome and the production of vIRF4 circRNAs. No circRNA was detectable from the PAN region. We found that the 57KO alters the RNA splicing efficiency of targeted viral RNAs. Two most susceptible RNAs to ORF57 splicing regulation are the K15 RNA with eight exons and seven introns and the bicistronic RNA encoding both viral thymidylate synthase (ORF70) and membrane-associated E3-ubiquitin ligase (K3). ORF57 inhibits splicing of both K15 introns 1 and 2. ORF70/K3 RNA bears two introns, of which the first intron is within the ORF70 coding region as an alternative intron and the second intron in the intergenic region between the ORF70 and K3 as a constitutive intron. In the WT cells expressing ORF57, most ORF70/K3 transcripts retain the first intron to maintain an intact ORF70 coding region. In contrast, in the 57KO cells, the first intron is substantially spliced out. Using a minigene comprising of ORF70/K3 locus, we further confirmed ORF57 regulation of ORF70/K3 RNA splicing, independently of other viral factors. By monitoring protein expression, we showed that ORF57-mediated retention of the first intron leads to the expression of full-length ORF70 protein. The absence of ORF57 promotes the first intron splicing and expression of K3 protein. Altogether, we conclude that ORF57 regulates alternative splicing of ORF70/K3 bicistronic RNA to control K3-mediated immune evasion and ORF70 participation of viral DNA replication in viral lytic infection.


Asunto(s)
Herpesvirus Humano 8 , Proteínas Represoras/genética , Transactivadores/genética , Replicación del ADN , ADN Viral/metabolismo , Regulación Viral de la Expresión Génica , Genoma Viral , Herpesvirus Humano 8/fisiología , Empalme del ARN/genética , ARN Viral/genética , ARN Viral/metabolismo , Proteínas de Unión al ARN/metabolismo , Replicación Viral/genética
3.
J Virol ; 96(3): e0178221, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-34787459

RESUMEN

Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 is an RNA-binding posttranscriptional regulator. We recently applied an affinity-purified anti-ORF57 antibody to conduct ORF57 cross-linking immunoprecipitation (CLIP) in combination with RNA-sequencing (CLIP-seq) and analyzed the genome-wide host RNA transcripts in association with ORF57 in BCBL-1 cells with lytic KSHV infection. Mapping of the CLIP RNA reads to the human genome (GRCh37) revealed that most of the ORF57-associated RNA reads were from rRNAs. The remaining RNA reads mapped to several classes of host noncoding and protein-coding mRNAs. We found that ORF57 binds and regulates expression of a subset of host long noncoding RNAs (lncRNAs), including LINC00324, LINC00355, and LINC00839, which are involved in cell growth. ORF57 binds small nucleolar RNAs (snoRNAs) responsible for 18S and 28S rRNA modifications but does not interact with fibrillarin or NOP58. We validated ORF57 interactions with 67 snoRNAs by ORF57 RNA immunoprecipitation (RIP)-snoRNA array assays. Most of the identified ORF57 rRNA binding sites (BS) overlap the sites binding snoRNAs. We confirmed ORF57-snoRA71B RNA interaction in BCBL-1 cells by ORF57 RIP and Northern blot analyses using a 32P-labeled oligonucleotide probe from the 18S rRNA region complementary to snoRA71B. Using RNA oligonucleotides from the rRNA regions that ORF57 binds for oligonucleotide pulldown-Western blot assays, we selectively verified ORF57 interactions with 5.8S and 18S rRNAs. Polysome profiling revealed that ORF57 associates with both monosomes and polysomes and that its association with polysomes increases PABPC1 binding to polysomes but prevents Ago2 association with polysomes. Our data indicate a functional correlation with ORF57 binding and suppression of Ago2 activities for ORF57 promotion of gene expression. IMPORTANCE As an RNA-binding protein, KSHV ORF57 regulates RNA splicing, stability, and translation and inhibits host innate immunity by blocking the formation of RNA granules in virus-infected cells. In this study, ORF57 was found to interact with many host noncoding RNAs, including lncRNAs, snoRNAs, and rRNAs, to carry out additional unknown functions. ORF57 binds a group of lncRNAs via the RNA motifs identified by ORF57 CLIP-seq to regulate their expression. ORF57 associates with snoRNAs independently of fibrillarin and NOP58 proteins and with rRNA in the regions that commonly bind snoRNAs. Knockdown of fibrillarin expression decreases the expression of snoRNAs and CDK4 but does not affect viral gene expression. More importantly, we found that ORF57 binds translationally active polysomes and enhances PABPC1 but prevents Ago2 association with polysomes. Data provide compelling evidence on how ORF57 in KSHV-infected cells might regulate protein synthesis by blocking Ago2's hostile activities on translation.


Asunto(s)
Infecciones por Herpesviridae/genética , Infecciones por Herpesviridae/virología , Herpesvirus Humano 8/fisiología , Interacciones Huésped-Patógeno/genética , Polirribosomas/metabolismo , ARN no Traducido/genética , Proteínas Reguladoras y Accesorias Virales/metabolismo , Regulación de la Expresión Génica , Regulación Viral de la Expresión Génica , Estudio de Asociación del Genoma Completo , Infecciones por Herpesviridae/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Conformación de Ácido Nucleico , Unión Proteica , Proteínas de Unión al ARN/metabolismo , Replicación Viral
4.
J Natl Compr Canc Netw ; 22(1D): e237079, 2023 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-38150820

RESUMEN

This report presents the case of a 62-year-old woman who was diagnosed in 1999 with stage I cervical carcinoma treated by surgical resection. In 2021, she presented to the emergency department with a complaint of predominantly right-sided lower back pain. A CT scan of the lumbosacral region revealed a bone lesion in the L5 vertebra and retroperitoneal lymphadenopathies suggestive of malignancy. Histology of the L5 vertebra biopsy showed a poorly differentiated carcinoma with an inconclusive immunophenotypic profile. Treatment for carcinoma of unknown primary was started with a combination of carboplatin and paclitaxel every 21 days. A genomic study of the biopsy specimen performed on the FoundationOne CDx platform identified a nonhuman genetic signature compatible with HPV. The presence of HPV 18 DNA in the specimen was confirmed by PCR-reverse dot blot, and the immunophenotypic profile was expanded, revealing strong and diffuse p16 expression, thus corroborating the molecular findings. In view of these findings, the case was reclassified as a recurrence of the cervical adenocarcinoma that had been diagnosed and treated 23 years earlier. Based on the new results, and according to first-line cervical carcinoma protocols, bevacizumab at 15 mg/kg every 21 days was added to her chemotherapy regimen. The identification of HPV DNA sequences by next-generation sequencing facilitated the correct diagnosis and led to a modification of the first-line therapeutic approach.


Asunto(s)
Carcinoma , Neoplasias Primarias Desconocidas , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Femenino , Persona de Mediana Edad , Neoplasias Primarias Desconocidas/diagnóstico , Neoplasias Primarias Desconocidas/tratamiento farmacológico , Neoplasias Primarias Desconocidas/genética , Carcinoma/tratamiento farmacológico , Bevacizumab , Paclitaxel/uso terapéutico , Neoplasias del Cuello Uterino/patología
5.
Phys Chem Chem Phys ; 25(3): 2486-2497, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36602075

RESUMEN

In this work, we present a Deuteron Nuclear Magnetic Resonance (DNMR) study of the non-symmetric odd liquid crystal dimer α-(4-cyanobiphenyl-4'-yloxy)-ω-(1-pyrenimine-benzylidene-4'-oxy) heptane (CBO7O.Py), formed by a pro-mesogenic cyanobiphenyl unit and a bulky pyrene-containing unit, linked via alkoxy flexible chain. We have synthesized two partially deuterated samples: one with the deuterium atoms in the cyanobiphenyl moiety (dCBO7O.Py) and the other one with the deuterium atoms in the pyrenimine-benzylidene unit (CBO7O.dPy). We have performed angular distribution analysis in the SmA glassy state, obtaining the degree of order of both rigid cores and an estimation of the internal molecular angle between both structures. With the results from the angular study, we have been able to determine the degree of order of both rigid units in either the N phase and the SmA phase, far enough from the glass transition. Both rigid cores have the same degree of order close to the nematic-isotropic phase transition, but as the compound is cooled down, the degree of order of the cyanobiphenyl moiety is clearly higher than that of the pyrene-containing unit. The critical behaviour of the order parameter of the pyrene-containing moiety is consistent with the fact that, for CBO7O.Py, the N-I phase transition is tricritical, which seems to indicate that the uniaxial order parameter of the dimer is dominated by the degree of order of the pyrene-containing core.

6.
Colorectal Dis ; 25(11): 2187-2197, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37743721

RESUMEN

AIM: To monitor prospectively the occurrence of colorectal anastomotic leakage (CAL) in patients with colon cancer undergoing resectional surgery, characterizing the microbiota in both faeces and mucosal biopsies of anastomosis. In a second stage, we investigated the ability to predict CAL using machine learning models based on clinical data and microbiota composition. METHOD: A total of 111 patients were included, from whom a faecal sample was obtained, as well as biopsy samples from proximal and distal sites in the healthy margins of the tumour piece. The microorganisms present in the samples were investigated using microbial culture and 16S rDNA massive sequencing. Collagenase and protease production was determined, as well as the presence of genes responsible for expressing enzymes with these activities. Machine learning analyses were developed using clinical and microbiological data. RESULTS: The incidence of CAL was 9.0%, and CAL was associated with collagenase/protease-producing Enterococcus. Significant differences were found in the microbiota composition of proximal and distal biopsy samples, but not in faecal samples, among patients who developed CAL. Clinical predictors of CAL were 5-day C-reactive protein and heart disease, whereas 3-day C-reactive protein and diabetes were negative predictors. CONCLUSION: Biopsy samples from surgical margins, rather than faecal samples, are the most appropriate samples for exploring the contribution of the intestinal microbiota to CAL. Enterococci are only enriched in the anastomosis after surgery, and their collagenases and proteases are involved in the degradation of the anastomotic scar.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Microbioma Gastrointestinal , Humanos , Fuga Anastomótica/etiología , Fuga Anastomótica/epidemiología , Proteína C-Reactiva , Anastomosis Quirúrgica/efectos adversos , Neoplasias del Colon/complicaciones , Colagenasas , Péptido Hidrolasas , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/complicaciones
7.
Inorg Chem ; 61(30): 11651-11666, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35838657

RESUMEN

Three copper(II)/mesoxalate-based MOFs with formulas (H3O)[Cu9(Hmesox)6(H2O)6Cl]·8H2O (1), (NH2Me2)0.4(H3O)0.6[Cu9(Hmesox)6(H2O)6Cl]·8H2O (2), and (enH2)0.25(enH)1.5[Cu6(Hmesox)3(mesox)(H2O)6Cl0.5]Cl0.5·5.25H2O (3) were synthesized (H4mesox = mesoxalic acid = 2,2-dihydroxypropanedioic acid, en = ethylenediamine). Essentially, all of the compounds display the same anionic network with a different arrangement of the cations, which have a remarkable effect on the proton conduction of the materials, ranging from 1.16 × 10-4 S cm-1 for 1 to 1.87 × 10-3 S cm-1 for 3 (at 80 °C and 95% RH). These compounds also display antiferromagnetic coupling among the copper(II) ions through both the carboxylate and alkoxido bridges. The values of the principal magnetic coupling constants were calculated by density functional theory (DFT), leading to congruent values that confirm the predominant antiferromagnetic nature of the interactions.

8.
Phys Chem Chem Phys ; 24(39): 24095-24104, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36178044

RESUMEN

Cycloparaphenylenes, being the smallest segments of carbon nanotubes, have emerged as prototypes of the simplest carbon nanohoops. Their unique structure-dynamics-optical properties relationships have motivated a wide variety of synthesis of new related nanohoop species. Studies of how chemical changes, introduced in these new materials, lead to systems with new structural, dynamics and optical properties, expand their functionalities for optoelectronics applications. Herein, we study the effect that conjugation extension of a cycloparaphenylene through the introduction of a satellite tetraphenyl substitution has on its structural and dynamical properties. Our non-adiabatic excited state molecular dynamics simulations suggest that this substitution accelerates the electronic relaxation from the high-energy band to the lowest excited state. This is partially due to efficient conjugation achieved between specific phenyl units as introduced by the tetraphenyl substitution. We observe a particular exciton redistribution during relaxation, in which the tetraphenyl substitution plays a significant role. As a result, an efficient inter-band energy transfer takes place. Besides, the observed phonon-exciton interplay induces a significant exciton self-trapping. Our results encourage and guide the future studies of new phenyl substitutions in carbon nanorings with desired optoelectronic properties.

9.
Pediatr Int ; 64(1): e15183, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36348518

RESUMEN

BACKGROUND: Knowledge of chronic kidney disease (CKD) with pubertal disorders (PD) in adolescent boys is limited as few studies have explored this disorder. This study aimed to identify the usefulness of assessing hormonal parameters in male adolescents with CKD and their correlation with PD in a 12-month follow-up period. METHODS: A prospective cohort study was conducted among male adolescents with CKD (stages IV and V). Data regarding the age at puberty onset were collected from the patients' clinical records and through interview. The patients were followed up for 12 months during their pubertal development. At the beginning, routine hormonal profile tests were performed to examine the patients' thyroid profile, prolactin levels, luteinizing hormone, follicle-stimulating hormone, testosterone, leptin, and receptor leptin. The hormonal profiles of patients with and without PD were compared. Comparisons between the groups were performed using the Student t-test and Fisher's exact tests. Logistic regression analysis was also performed. RESULTS: Data of 64 patients (26/64 with PD) were analyzed. The median age was 15 years and the median time for CKD evolution was 11 months. No differences between groups were noted in the general or biochemical characteristics of the patients. The hormonal parameters, prolactin levels were higher and the free leptin and free thyroxine levels were lower in patients with PD. Leptin receptor levels of >0.90 ng/mL (risk ratio [RR], 8.6; P = 0.004) and hyperprolactinemia (RR, 21.3; P = 0.049) were the risk factors for PD. CONCLUSIONS: Leptin receptor levels of >0.90 ng/mL and hyperprolactinemia are associated with the development of PD in male adolescents with CKD.


Asunto(s)
Hiperprolactinemia , Insuficiencia Renal Crónica , Adolescente , Humanos , Masculino , Receptores de Leptina , Prolactina , Leptina , Hiperprolactinemia/complicaciones , Estudios Prospectivos , Pubertad , Insuficiencia Renal Crónica/complicaciones
10.
J Neurochem ; 156(6): 897-916, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32750173

RESUMEN

Extrasynaptic α5 -subunit containing GABAA (α5 -GABAA ) receptors participate in chronic pain. Previously, we reported a sex difference in the action of α5 -GABAA receptors in dysfunctional pain. However, the underlying mechanisms remain unknown. The aim of this study was to examine this sexual dimorphism in neuropathic rodents and the mechanisms involved. Female and male Wistar rats or ICR mice were subjected to nerve injury followed by α5 -GABAA receptor inverse agonist intrathecal administration, L-655,708. The drug produced an antiallodynic effect in nerve-injured female rats and mice, and a lower effect in males. We hypothesized that changes in α5 -GABAA receptor, probably influenced by hormonal and epigenetic status, might underlie this sex difference. Thus, we performed qPCR and western blot. Nerve injury increased α5 -GABAA mRNA and protein in female dorsal root ganglia (DRG) and decreased them in DRG and spinal cord of males. To investigate the hormonal influence over α5 -GABAA receptor actions, we performed nerve injury to ovariectomized rats and reconstituted them with 17ß-estradiol (E2). Ovariectomy abrogated L-655,708 antiallodynic effect and E2 restored it. Ovariectomy decreased α5 -GABAA receptor and estrogen receptor α protein in DRG of neuropathic female rats, while E2 enhanced them. Since DNA methylation might contribute to α5 -GABAA receptor down-regulation in males, we examined CpG island DNA methylation of α5 -GABAA receptor coding gene through pyrosequencing. Nerve injury increased methylation in male, but not female rats. Pharmacological inhibition of DNA methyltransferases increased α5 -GABAA receptor and enabled L-655,708 antinociceptive effect in male rats. These results suggest that α5 -GABAA receptor is a suitable target to treat chronic pain in females.


Asunto(s)
Epigénesis Genética/genética , Nocicepción/fisiología , Enfermedades del Sistema Nervioso Periférico/genética , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Receptores de GABA-A/genética , Receptores de GABA-A/fisiología , Animales , Metilación de ADN/genética , Estradiol/farmacología , Femenino , Agonistas del GABA/administración & dosificación , Agonistas del GABA/farmacología , Ganglios Espinales/metabolismo , Imidazoles/farmacología , Inyecciones Espinales , Masculino , Ratones , Ratones Endogámicos ICR , Ovariectomía , Dimensión del Dolor , Ratas , Ratas Wistar , Caracteres Sexuales
11.
Am J Hum Genet ; 103(5): 786-793, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30343942

RESUMEN

PCGF2 encodes the polycomb group ring finger 2 protein, a transcriptional repressor involved in cell proliferation, differentiation, and embryogenesis. PCGF2 is a component of the polycomb repressive complex 1 (PRC1), a multiprotein complex which controls gene silencing through histone modification and chromatin remodelling. We report the phenotypic characterization of 13 patients (11 unrelated individuals and a pair of monozygotic twins) with missense mutations in PCGF2. All the mutations affected the same highly conserved proline in PCGF2 and were de novo, excepting maternal mosaicism in one. The patients demonstrated a recognizable facial gestalt, intellectual disability, feeding problems, impaired growth, and a range of brain, cardiovascular, and skeletal abnormalities. Computer structural modeling suggests the substitutions alter an N-terminal loop of PCGF2 critical for histone biding. Mutant PCGF2 may have dominant-negative effects, sequestering PRC1 components into complexes that lack the ability to interact efficiently with histones. These findings demonstrate the important role of PCGF2 in human development and confirm that heterozygous substitutions of the Pro65 residue of PCGF2 cause a recognizable syndrome characterized by distinctive craniofacial, neurological, cardiovascular, and skeletal features.

12.
Euro Surveill ; 26(18)2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33960288

RESUMEN

Despite social distancing measures implemented in Madrid to prevent the propagation of SARS-CoV-2, a significant increase (57.1%; 28.5 to 38.5 cases/month) in cases of lymphogranuloma venereum was detected during the COVID-19 pandemic. This unusual scenario might have accelerated a shift in Chlamydia trachomatis (CT) epidemiology towards a higher proportion of L genotypes compared with non-L genotypes in CT-positive samples. Our data underscore the importance of surveillance of sexually transmitted infections during the pandemic, in particular among vulnerable populations.


Asunto(s)
COVID-19 , Linfogranuloma Venéreo , Chlamydia trachomatis/genética , Homosexualidad Masculina , Humanos , Linfogranuloma Venéreo/diagnóstico , Linfogranuloma Venéreo/epidemiología , Masculino , Pandemias , SARS-CoV-2 , España/epidemiología
13.
Sensors (Basel) ; 21(1)2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33401468

RESUMEN

This paper presents an efficient cyberphysical platform for the smart management of smart territories. It is efficient because it facilitates the implementation of data acquisition and data management methods, as well as data representation and dashboard configuration. The platform allows for the use of any type of data source, ranging from the measurements of a multi-functional IoT sensing devices to relational and non-relational databases. It is also smart because it incorporates a complete artificial intelligence suit for data analysis; it includes techniques for data classification, clustering, forecasting, optimization, visualization, etc. It is also compatible with the edge computing concept, allowing for the distribution of intelligence and the use of intelligent sensors. The concept of smart cities is evolving and adapting to new applications; the trend to create intelligent neighbourhoods, districts or territories is becoming increasingly popular, as opposed to the previous approach of managing an entire megacity. In this paper, the platform is presented, and its architecture and functionalities are described. Moreover, its operation has been validated in a case study where the bike renting service of Paris-Vélib' Métropole has been managed. This platform could enable smart territories to develop adapted knowledge management systems, adapt them to new requirements and to use multiple types of data, and execute efficient computational and artificial intelligence algorithms. The platform optimizes the decisions taken by human experts through explainable artificial intelligence models that obtain data from IoT sensors, databases, the Internet, etc. The global intelligence of the platform could potentially coordinate its decision-making processes with intelligent nodes installed in the edge, which would use the most advanced data processing techniques.

14.
Soft Matter ; 16(42): 9738-9745, 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-32996537

RESUMEN

Single-chain polymer nanoparticles (SCNPs) are soft nano-objects consisting of uni-macromolecular chains collapsed to a certain degree by intramolecular crosslinking. The similarities between the behaviour of SCNPs and that of intrinsically disordered proteins suggest that SCNPs in concentrated solutions can be used as models to design artificial micro-environments, which mimic many of the general aspects of cellular environments. In this work, the self-assembly into SCNPs of an amphiphilic random copolymer, composed by oligo(ethylene glycol)methyl ether methacrylate (OEGMA) and 2-acetoacetoxy ethyl methacrylate (AEMA), has been investigated by means of the dielectric relaxation of water. Direct evidence of segregation of the AEMA repeating units is provided by comparison with the dielectric relaxation of water in similar solutions of the linear hydrophilic polymer, P(OEGMA). Furthermore, the results of comparative studies with similar water solutions of an amphiphilic block copolymer forming multi-chain micelles support the single-chain character of the self-assembly of the random copolymer. The overall obtained results highlight the suitability of the dielectric spectroscopy to confirm the self-assembly of the amphiphilic random copolymers into globular like core-shell single-chain nanoparticles at a concentration well above the overlap concentration.


Asunto(s)
Nanopartículas , Agua , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Polímeros
15.
Pediatr Nephrol ; 35(6): 1041-1049, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32040631

RESUMEN

BACKGROUND: In adolescents with chronic kidney disease (CKD), menstrual disorders (MD) are common, which can make the management of CKD difficult and can sometimes delay renal transplantation. This study aimed to identify the usefulness of hormonal measurements in adolescents with CKD and their relationships with MD during a 1-year follow-up. METHODS: A prospective cohort study was designed. Adolescents with CKD stages IV and V were included. Through clinical files and via interview, the ages at puberty onset, menarche and the date of last menstruation were identified. A 1-year follow-up was conducted over a menstrual cycle calendar. At the beginning of follow-up, routine hormonal profiles (thyroid profiles, prolactin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol) were assessed. We compared the hormonal profiles of the patients with and without MD (wMD vs. woMD). Comparisons between groups were made by Wilcoxon and Fisher's tests. Logistic regression analysis was used. RESULTS: Fifty-seven patients, including 30 patients classified as wMD, were analyzed. The median age was 15 years, and the median time of CKD evolution was 18 months. There were no differences in general and biochemical characteristics between patients wMD and woMD. In terms of hormonal measurements, the levels of thyroid-stimulating hormone (TSH) and prolactin were higher in the wMD patients. A prolactin level ≥ 36.8 ng/ml was a risk factor for presenting with MD (RR 34.4, p = 0.002). CONCLUSIONS: Hyperprolactinemia is correlated with MD in adolescents with CKD.


Asunto(s)
Hiperprolactinemia/complicaciones , Trastornos de la Menstruación/etiología , Insuficiencia Renal Crónica/complicaciones , Adolescente , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hiperprolactinemia/sangre , Hiperprolactinemia/diagnóstico , Trastornos de la Menstruación/sangre , Estudios Prospectivos , Factores de Riesgo , Tirotropina/sangre
16.
Rev Invest Clin ; 72(5)2020 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33053575

RESUMEN

BACKGROUND: Hepatocarcinogenesis has a variety of risk factors. In Mexico City, autopsies found 14% of hepatocellular carcinomas (HCCs) without cirrhosis. OBJECTIVE: The objective of the study was to explore if HCCs carry the TP53 R249S mutation that has linked them to aflatoxin exposure and describe the associated risk factors. METHODS: A retrospective review of consecutive cases of HCC was performed. Exposure to hepatotropic viruses, alcoholism, metabolic diseases, diabetes mellitus, and hypertension, as well as episodes of ascites, portal hypertension, and body mass index were retrieved. Slides were re-reviewed, macrodissected and DNA was extracted. TP53 exon 7 was amplified, purified, and used as a template for sequencing. RESULTS: In 14 years, 74 HCCs were identified in 1863 (4%) consecutive liver biopsies. No data were available in five excluded patients; the rest was submitted to exon 7 screening. Patients had a median age of 62 years, and 46 (67%) were male. Stage 4 fibrosis was observed in 46 patients (67%) and their associated risk factors were hepatitis C virus (39%, 18/46), alcoholism (20%, 9/46), hepatitis B virus (2%, 1/46), and 18 were cryptogenic. Fibrosis stage 3 or lower was observed in 23 (33%) patients without demonstrated liver disease; 8/23 had diabetes and 6/23, systemic hypertension. Steatohepatitic variants of HCC were observed in 4 and in 5, the remnant liver had steatohepatitis. A 238-bp fragment was obtained in each tumor without the expected TP53 R249S mutation. CONCLUSIONS: There was no evidence of aflatoxin exposure in HCCs, with and without the known "classical" risk factors. One-third of non-cirrhotic HCCs had steatohepatitis or conditions associated to metabolic syndrome.

18.
BMC Neurol ; 19(1): 326, 2019 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-31842821

RESUMEN

BACKGROUND: Mild Cognitive Impairment (MCI) carries a high risk of progression to Alzheimer's disease (AD) dementia. Previous clinical trials testing whether cholinesterase inhibitors can slow the rate of progression from MCI to AD dementia have yielded disappointing results. However, recent studies of the effects of repetitive transcranial magnetic stimulation (rTMS) in AD have demonstrated improvements in cognitive function. Because few rTMS trials have been conducted in MCI, we designed a trial to test the short-term efficacy of rTMS in MCI. Yet, in both MCI and AD, we know little about what site of stimulation would be ideal for improving cognitive function. Therefore, two cortical sites will be investigated in this trial: (1) the dorsolateral prefrontal cortex (DLPFC), which has been well studied for treatment of major depressive disorder; and (2) the lateral parietal cortex (LPC), a novel site with connectivity to AD-relevant limbic regions. METHODS/DESIGN: In this single-site trial, we plan to enroll 99 participants with single or multi-domain amnestic MCI. We will randomize participants to one of three groups: (1) Active DLPFC rTMS; (2) Active LPC rTMS; and (3) Sham rTMS (evenly split between DLPFC and LPC locations). After completing 20 bilateral rTMS treatment sessions, participants will be followed for 6 months to test short-term efficacy and track durability of effects. The primary efficacy measure is the California Verbal Learning Test-II (CVLT-II), assessed 1 week after intervention. Secondary analyses will examine effects of rTMS on other cognitive measures, symptoms of depression, and brain function with respect to the site of stimulation. Finally, selected biomarkers will be analyzed to explore predictors of response and mechanisms of action. DISCUSSION: The primary aim of this trial is to test the short-term efficacy of rTMS in MCI. Additionally, the project will provide information on the durability of cognitive effects and potentially distinct effects of stimulating DLPFC versus LPC regions. Future efforts would be directed toward better understanding therapeutic mechanisms and optimizing rTMS for treatment of MCI. Ultimately, if rTMS can be utilized to slow the rate of progression to AD dementia, this will be a significant advancement in the field. TRIAL REGISTRATION: Clinical Trials NCT03331796. Registered 6 November 2017, https://clinicaltrials.gov/ct2/show/NCT03331796. All items from the World Health Organization Trial Registration Data Set are listed in Appendix A. PROTOCOL VERSION: This report is based on version 1, approved by the DSMB on 30 November, 2017 and amended on 14 August, 2018 and 19 September, 2019.


Asunto(s)
Disfunción Cognitiva/terapia , Lóbulo Parietal , Corteza Prefrontal , Proyectos de Investigación , Estimulación Magnética Transcraneal/métodos , Anciano , Femenino , Humanos , Masculino
19.
Macromol Rapid Commun ; 40(9): e1900046, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30801882

RESUMEN

Access to completely deuterated single-chain nanoparticles (dSCNPs) has remained an unresolved issue. Herein, the first facile and efficient procedure to produce dSCNPs is reported, which comprises: i) the use of commercially available perdeuterated cyclic ether monomers as starting reagents, ii) a ring-opening copolymerization process performed in bulk to produce a neat dSCNP precursor, iii) a standard azidation reaction to decorate this precursor with azide moieties, and iv) a facile intramolecular azide photodecomposition step carried out under UV irradiation at high dilution providing with highly valuable, completely deuterated soft nano-objects from the precursor. dSCNPs are used to investigate by means of neutron-scattering measurements the form factor (radius of gyration, scaling exponent) of polyethylene oxide (PEO) chains in nanocomposites with different amounts of dSCNPs. Moreover, to illustrate the possibilities offered by the synthetic route disclosed in this communication for potential applications, the significant reduction in viscosity observed in a pure melt of polyether-based single-chain nanoparticles when compared to a melt of the corresponding linear polymer chains is shown.


Asunto(s)
Azidas/química , Deuterio/química , Nanopartículas/química , Neutrones
20.
Acta Vet Hung ; 67(3): 317-326, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31549546

RESUMEN

The aim of this study was to determine the prevalence of methicillin-resistant Staphylococcus (MRS) in healthy goats on the Island of Tenerife, Spain, as well as to identify the phenotypic and genotypic characteristics of the strains found. A cross-sectional prevalence study was conducted. A total of 158 goats from 15 different farms were sampled between September 2017 and January 2018. The percentage of positive samples of methicillin-resistant Staphylococcus aureus (MRSA) was 15.8% (25/158) and that of methicillin-resistant coagulase-negative staphylococci (MRCoNS) was 6.9% (11/158). All MRSA isolates from goats belonged to one clonal group showing Multi-Locus Sequence type 398. All strains studied (n = 36) were resistant to non-carbapenem beta-lactam antibiotics and susceptible to teicoplanin, linezolid, vancomycin, rifampicin, quinupristin-dalfospristin and mupirocine. In MRSA isolates, the highest percentage of resistance obtained, besides beta-lactam non-carbapenem antibiotics, was to trimethoprim-sulphamethoxazole and, in the case of MRCoNS isolates, to phosphomycin and erythromycin. A total of 12 resistance patterns were obtained, presenting differences between patterns obtained for MRSA and MRCoNS, with 7 different patterns for MRSA and 5 for MRCoNS. We therefore consider it essential to expand the epidemiological study of these strains of animal origin, as well as to increase surveillance and control measures at all stages of the food chain.


Asunto(s)
Enfermedades de las Cabras/epidemiología , Staphylococcus aureus Resistente a Meticilina/fisiología , Infecciones Estafilocócicas/veterinaria , Animales , Estudios Transversales , Cabras , Prevalencia , España/epidemiología , Infecciones Estafilocócicas/epidemiología
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