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1.
Biophys J ; 123(2): 134-146, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38073154

RESUMEN

The aqueous environment inside cells is densely packed. A typical cell has a macromolecular concentration in the range 90-450 g/L, with 5%-40% of its volume being occupied by macromolecules, resulting in what is known as macromolecular crowding. The space available for the free diffusion of metabolites and other macromolecules is thus greatly reduced, leading to so-called excluded volume effects. The slow diffusion of macromolecules under crowded conditions has been explained using transient complex formation. However, sub-diffusion noted in earlier works is not well characterized, particularly the role played by transient complex formation and excluded volume effects. We have used Brownian dynamics simulations to characterize the diffusion of chymotrypsin inhibitor 2 in protein solutions of bovine serum albumin and lysozyme at concentrations ranging from 50 to 300 g/L. The predicted changes in diffusion coefficient as a function of crowder concentration are consistent with NMR experiments. The sub-diffusive behavior observed in the sub-microsecond timescale can be explained in terms of a so-called cage effect, arising from rattling motion in a local molecular cage as a consequence of excluded volume effects. By selectively manipulating the nature of interactions between protein molecules, we determined that excluded volume effects induce sub-diffusive dynamics at sub-microsecond timescales. These findings may help to explain the diffusion-mediated effects of protein crowding on cellular processes.


Asunto(s)
Simulación de Dinámica Molecular , Proteínas , Proteínas/química , Movimiento (Física) , Sustancias Macromoleculares/química , Agua/química , Difusión , Soluciones
2.
Chemistry ; : e202401695, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889267

RESUMEN

Glycoconjugate vaccines are based on chemical conjugation of pathogen-associated carbohydrates with immunogenic carrier proteins and are considered a very cost-effective way to prevent infections. Most of the licensed glycoconjugate vaccines are composed of saccharide antigens extracted from bacterial sources. However, synthetic oligosaccharide antigens have become a promising alternative to natural polysaccharides with the advantage of being well-defined structures providing homogeneous conjugates. Haemophilus influenzae (Hi) is responsible for a number of severe diseases. In recent years, an increasing rate of invasive infections caused by Hi serotype a (Hia) raised some concern, because no vaccine targeting Hia is currently available. The capsular polysaccharide (CPS) of Hia is constituted by phosphodiester-linked 4-ß-d-glucose-(1→4)-d-ribitol-5-(PO4→) repeating units and is the antigen for protein-conjugated polysaccharide vaccines. To investigate the antigenic potential of the CPS from Hia, we synthesized related saccharide fragments containing up to five repeating units. Following the synthetic optimization of the needed disaccharide building blocks, they were assembled using the phosphoramidite approach for the installation of the phosphodiester linkages. The resulting CPS-based Hia oligomers were conjugated to CRM197 carrier protein and evaluated in vivo for their immunogenic potential, showing that all glycoconjugates were capable of raising antibodies recognizing Hia synthetic fragments.

3.
Chem Rev ; 122(20): 15672-15716, 2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-35608633

RESUMEN

Antimicrobial resistance (AMR) is emerging as the next potential pandemic. Different microorganisms, including the bacteria Acinetobacter baumannii, Clostridioides difficile, Escherichia coli, Enterococcus faecium, Klebsiella pneumoniae, Neisseria gonorrhoeae, Pseudomonas aeruginosa, non-typhoidal Salmonella, and Staphylococcus aureus, and the fungus Candida auris, have been identified by the WHO and CDC as urgent or serious AMR threats. Others, such as group A and B Streptococci, are classified as concerning threats. Glycoconjugate vaccines have been demonstrated to be an efficacious and cost-effective measure to combat infections against Haemophilus influenzae, Neisseria meningitis, Streptococcus pneumoniae, and, more recently, Salmonella typhi. Recent times have seen enormous progress in methodologies for the assembly of complex glycans and glycoconjugates, with developments in synthetic, chemoenzymatic, and glycoengineering methodologies. This review analyzes the advancement of glycoconjugate vaccines based on synthetic carbohydrates to improve existing vaccines and identify novel candidates to combat AMR. Through this literature survey we built an overview of structure-immunogenicity relationships from available data and identify gaps and areas for further research to better exploit the peculiar role of carbohydrates as vaccine targets and create the next generation of synthetic carbohydrate-based vaccines.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Antibacterianos/farmacología , Glicoconjugados/farmacología , Polisacáridos , Carbohidratos , Vacunas Sintéticas
4.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38612547

RESUMEN

Protein self-assembling nanoparticles (NPs) can be used as carriers for antigen delivery to increase vaccine immunogenicity. NPs mimic the majority of invading pathogens, inducing a robust adaptive immune response and long-lasting protective immunity. In this context, we investigated the potential of NPs of different sizes and shapes-ring-, rod-like, and spherical particles-as carriers for bacterial oligosaccharides by evaluating in murine models the role of these parameters on the immune response. Oligosaccharides from Neisseria meningitidis type W capsular polysaccharide were conjugated to ring-shape or nanotubes of engineered Pseudomonas aeruginosa Hemolysin-corregulated protein 1 (Hcp1cc) and to spherical Helicobacter pylori ferritin. Glycoconjugated NPs were characterized using advanced technologies such as High-Performance Liquid Chromatography (HPLC), Asymmetric Flow-Field Flow fractionation (AF4), and Transmission electron microscopy (TEM) to verify their correct assembly, dimensions, and glycosylation degrees. Our results showed that spherical ferritin was able to induce the highest immune response in mice against the saccharide antigen compared to the other glycoconjugate NPs, with increased bactericidal activity compared to benchmark MenW-CRM197. We conclude that shape is a key attribute over size to be considered for glycoconjugate vaccine development.


Asunto(s)
Antiinfecciosos , Nanopartículas , Animales , Ratones , Glicoconjugados , Ferritinas , Oligosacáridos
5.
Int J Mol Sci ; 25(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38791457

RESUMEN

Insulin-like peptide 3 (INSL3) is a biomarker for Leydig cells in the testes of vertebrates, and it is principally involved in spermatogenesis through specific binding with the RXFP2 receptor. This study reports the insl3 gene transcript and the Insl3 prepropeptide expression in both non-reproductive and reproductive tissues of Danio rerio. An immunohistochemistry analysis shows that the hormone is present at a low level in the Leydig cells and germ cells at all stages of Danio rerio testis differentiation. Considering that the insl3 gene is transcribed in Leydig cells, our results highlight an autocrine and paracrine function of this hormone in the Danio rerio testis, adding new information on the Insl3 mode of action in reproduction. We also show that Insl3 and Rxfp2 belonging to Danio rerio and other vertebrate species share most of the amino acid residues involved in the ligand-receptor interaction and activation, suggesting a conserved mechanism of action during vertebrate evolution.


Asunto(s)
Insulina , Insulinas , Proteínas , Receptores Acoplados a Proteínas G , Testículo , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/metabolismo , Masculino , Proteínas/metabolismo , Proteínas/genética , Insulina/metabolismo , Testículo/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Insulinas/metabolismo , Insulinas/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Células Intersticiales del Testículo/metabolismo , Secuencia de Aminoácidos , Espermatogénesis/genética
6.
J Cell Biochem ; 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36645880

RESUMEN

FKBP51 is constitutively expressed by immune cells. As other FKBP family members, FKBP51 acts as a coreceptor for the natural products FK506 and rapamycin, which exhibit immunosuppressive effects. However, little is known about the intrinsic role of this large FKBP in the primary function of lymphocytes, that is, the adaptive immune response against foreign antigens, for example, pathogens. This paper aimed to investigate whether FKBP51 expression was modulated during lymphocyte activation. Moreover, as we recently identified a splicing isoform of FKBP51, namely FKBP51s, we also measured this splice protein, along with the canonical one, at different times of a peripheral blood mononuclear cell culture stimulated via T cell receptor. Our results show that the two FKBP51 isoforms were alternatively induced during the proliferative burst. Canonical FKBP51 increased in the time window between 48 and 96 h and its expression levels correlated with cyclin D levels. FKBP51s transiently increased earlier, at 24-36 h to reappearing later, at 120 h, when cyclin D expression returned at resting levels and proliferation ceased. Interestingly, within these two specific timeframes, FKBP51s accumulated in the nucleus. Here FKBP51s colocalized with the Foxp3 transcription factor at 36 h. Regulatory T cell (Treg) counts significantly decreased when FKBP51s was downmodulated. The coculture suppression assay suggested that FKBP51s supports the suppressive capability of Tregs. At 120 h, chromatin immunoprecipitation experiments found FKBP51s linked to CCND1 gene, suggesting a possible effect on gene transcription regulation, as previously demonstrated in melanoma. In conclusion, our study shows that FKBP5 isoforms are upregulated during lymphocyte activation, albeit on different timeframes. The activation of canonical FKBP51 coincides with proliferation hallmarks; FKBP5 splicing occurs early to sustain Treg development and late when proliferation ceases.

7.
Am J Hum Genet ; 107(1): 34-45, 2020 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-32497488

RESUMEN

IFAP syndrome is a rare genetic disorder characterized by ichthyosis follicularis, atrichia, and photophobia. Previous research found that mutations in MBTPS2, encoding site-2-protease (S2P), underlie X-linked IFAP syndrome. The present report describes the identification via whole-exome sequencing of three heterozygous mutations in SREBF1 in 11 unrelated, ethnically diverse individuals with autosomal-dominant IFAP syndrome. SREBF1 encodes sterol regulatory element-binding protein 1 (SREBP1), which promotes the transcription of lipogenes involved in the biosynthesis of fatty acids and cholesterols. This process requires cleavage of SREBP1 by site-1-protease (S1P) and S2P and subsequent translocation into the nucleus where it binds to sterol regulatory elements (SRE). The three detected SREBF1 mutations caused substitution or deletion of residues 527, 528, and 530, which are crucial for S1P cleavage. In vitro investigation of SREBP1 variants demonstrated impaired S1P cleavage, which prohibited nuclear translocation of the transcriptionally active form of SREBP1. As a result, SREBP1 variants exhibited significantly lower transcriptional activity compared to the wild-type, as demonstrated via luciferase reporter assay. RNA sequencing of the scalp skin from IFAP-affected individuals revealed a dramatic reduction in transcript levels of low-density lipoprotein receptor (LDLR) and of keratin genes known to be expressed in the outer root sheath of hair follicles. An increased rate of in situ keratinocyte apoptosis, which might contribute to skin hyperkeratosis and hypotrichosis, was also detected in scalp samples from affected individuals. Together with previous research, the present findings suggest that SREBP signaling plays an essential role in epidermal differentiation, skin barrier formation, hair growth, and eye function.


Asunto(s)
Artrogriposis/genética , Mutación/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Regulación de la Expresión Génica/genética , Humanos , Queratosis/genética , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Adulto Joven
8.
Diabetes Metab Res Rev ; 39(7): e3690, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37422897

RESUMEN

AIMS: The current study aims to evaluate the effectiveness of a multidisciplinary diabetic foot team (MDFT) in the management of in-patients affected by diabetic foot problems. MATERIALS AND METHODS: The study was a retrospective observational study. Consecutive patients with a diabetic foot problem requiring hospitalisation were included. All patients were managed by a MDFT led by diabetologists according to the guidance. The rate of in-hospital complications (IHCs), major amputation, and survival were recorded at the end of patient's hospitalisation. IHC was defined as any new infection different from wound infection, cardiovascular events, acute renal injury, severe anaemia requiring blood transfusion, and any other clinical problem not present at the assessment. RESULTS: Overall, 350 patients were included. The mean age was 67.9 ± 12.6 years, 254 (72.6%) were males, 323 (92, 3%) showed Type 2 diabetes with a mean duration of 20.2 ± 9.6 years; 224 (64%) had ischaemic diabetic foot ulcers (DFUs) and 299 (85.4%) had infected DFUs. IHCs were recorded in 30/350 (8.6%) patients. The main reasons for IHCs were anaemia requiring blood transfusion (2.8%), pneumonia (1.7%), acute kidney failure (1.1%). Patients with IHCs showed a higher rate of major amputation (13.3 vs. 3.1%, p = 0.02) and mortality (16.7 vs. 0.6%, p < 0.0001) in comparison to those without. Ischaemic heart disease (IHD) and wound duration at the assessment (>1 month) were independent predictors of IHC, whereas IHCs, heart failure, and dialysis were independent predictors of in-hospital mortality. CONCLUSIONS: The multidisciplinary management of diabetic foot problems leads to an IHC rate of 8%. The risk of IHCs is higher in patients with IHD and long wound duration.


Asunto(s)
Anemia , Enfermedad de la Arteria Coronaria , Diabetes Mellitus Tipo 2 , Pie Diabético , Masculino , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Femenino , Pie Diabético/terapia , Estudios Retrospectivos , Hospitales , Grupo de Atención al Paciente
9.
Glycoconj J ; 40(2): 135-148, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36652051

RESUMEN

Multivalent vaccines addressing an increasing number of Streptococcus pneumoniae types (7-, 10-, 13-, 15-, 20-valent) have been licensed over the last 22 years. The use of polysaccharide-protein conjugate vaccines has been pivotal in reducing the incidence of invasive pneumococcal disease despite the emergence of non-vaccine serotypes. Notwithstanding its undoubtable success, some weaknesses have called for continuous improvement of pneumococcal vaccination. For instance, despite their inclusion in pneumococcal conjugate vaccines, there are challenges associated with some serotypes. In particular, Streptococcus pneumoniae type 3 remains a major cause of invasive pneumococcal disease in several countries.Here a deep revision of the strengths and weaknesses of the licensed pneumococcal conjugate vaccines and other vaccine candidates currently in clinical development is reported.


Asunto(s)
Infecciones Neumocócicas , Vacunas Neumococicas , Humanos , Vacunas Neumococicas/uso terapéutico , Streptococcus pneumoniae , Infecciones Neumocócicas/prevención & control , Infecciones Neumocócicas/epidemiología , Vacunación , Vacunas Conjugadas/uso terapéutico , Anticuerpos Antibacterianos
10.
Proc Natl Acad Sci U S A ; 117(47): 29795-29802, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33158970

RESUMEN

Meningococcal meningitis remains a substantial cause of mortality and morbidity worldwide. Until recently, countries in the African meningitis belt were susceptible to devastating outbreaks, largely attributed to serogroup A Neisseria meningitidis (MenA). Vaccination with glycoconjugates of MenA capsular polysaccharide led to an almost complete elimination of MenA clinical cases. To understand the molecular basis of vaccine-induced protection, we generated a panel of oligosaccharide fragments of different lengths and tested them with polyclonal and monoclonal antibodies by inhibition enzyme-linked immunosorbent assay, surface plasmon resonance, and competitive human serum bactericidal assay, which is a surrogate for protection. The epitope was shown to optimize between three and six repeating units and to be O-acetylated. The molecular interactions between a protective monoclonal antibody and a MenA capsular polysaccharide fragment were further elucidated at the atomic level by saturation transfer difference NMR spectroscopy and X-ray crystallography. The epitope consists of a trisaccharide anchored to the antibody via the O- and N-acetyl moieties through either H-bonding or CH-π interactions. In silico docking showed that 3-O-acetylation of the upstream residue is essential for antibody binding, while O-acetate could be equally accommodated at three and four positions of the other two residues. These results shed light on the mechanism of action of current MenA vaccines and provide a foundation for the rational design of improved therapies.


Asunto(s)
Epítopos/inmunología , Meningitis Meningocócica/prevención & control , Vacunas Meningococicas/inmunología , Neisseria meningitidis/inmunología , Polisacáridos Bacterianos/inmunología , Acetilación , Adolescente , Anticuerpos Antibacterianos/química , Anticuerpos Antibacterianos/inmunología , Niño , Ensayos Clínicos Fase II como Asunto , Cristalografía por Rayos X , Femenino , Humanos , Inmunogenicidad Vacunal , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/inmunología , Masculino , Meningitis Meningocócica/inmunología , Meningitis Meningocócica/microbiología , Vacunas Meningococicas/uso terapéutico , Simulación del Acoplamiento Molecular , Estudios Multicéntricos como Asunto , Polisacáridos Bacterianos/química , Ensayos Clínicos Controlados Aleatorios como Asunto , Serogrupo , Determinación de Anticuerpos Séricos Bactericidas , Vacunas Conjugadas/inmunología , Vacunas Conjugadas/uso terapéutico
11.
Ecotoxicol Environ Saf ; 259: 115067, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37244200

RESUMEN

Cadmium (Cd), by producing oxidative stress and acting as an endocrine disruptor, is known to cause severe testicular injury, documented by histological and biomolecular alterations, such as decreased serum testosterone (T) level and impairment of spermatogenesis. This is the first report on the potential counteractive/preventive action of D-Aspartate (D-Asp), a well-known stimulator of T biosynthesis and spermatogenesis progression by affecting hypothalamic-pituitary-gonadal axis, in alleviating Cd effects in the rat testis. Our results confirmed that Cd affects testicular activity, as documented by the reduction of serum T concentration and of the protein levels of steroidogenesis (StAR, 3ß-HSD, and 17ß-HSD) and spermatogenesis (PCNA, p-H3, and SYCP3) markers. Moreover, higher protein levels of cytochrome C and caspase 3, together with the number of cells positive to TUNEL assay, indicated the intensification of the apoptotic process. D-Asp administered either simultaneously to Cd, or for 15 days before the Cd-treatment, reduced the oxidative stress induced by the metal, alleviating the consequent harmful effects. Interestingly, the preventive action of D-Asp was more effective than its counteractive effect. A possible explanation is that giving D-Asp for 15 days induces its significant uptake in the testes, reaching the concentrations necessary for optimum function. In summary, this report highlights, for the first time, the beneficial role played by D-Asp in both counteracting/preventing the adverse Cd effects in the rat testis, strongly encouraging further investigations to consider the potential value of D-Asp also in improving human testicular health and male fertility.


Asunto(s)
Cadmio , Testículo , Ratas , Humanos , Animales , Masculino , Cadmio/metabolismo , Ácido D-Aspártico/farmacología , Ácido D-Aspártico/metabolismo , Espermatogénesis , Estrés Oxidativo , Testosterona
12.
Sensors (Basel) ; 23(19)2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37836872

RESUMEN

Patients affected with type 1 diabetes and a non-negligible number of patients with type 2 diabetes are insulin dependent. Both the injection technique and the choice of the most suitable needle are fundamental for allowing them to have a good injection experience. The needles may differ in several parameters, from the length and diameter, up to the forces required to perform the injection and to some geometrical parameters of the needle tip (e.g., number of facets or bevels). The aim of the research is to investigate whether an increased number of bevels could decrease forces and energy involved in the insertion-extraction cycle, thus potentially allowing patients to experience lower pain. Two needle variants, namely, 31 G × 5 mm and 32 G × 4 mm, are considered, and experimental tests are carried out to compare 3-bevels with 5-bevels needles for both the variants. The analysis of the forces and energy for both variants show that the needles with 5 bevels require a statistically significant lower drag or sliding force (p-value = 0.040 for the 31 G × 5 mm needle and p-value < 0.001 for 32 G × 4 mm), extraction force (p-value < 0.001 for both variants), and energy (p-value < 0.001 for both variants) during the insertion-extraction cycle. As a result, 3-bevels needles do not have the same functionality of 5-bevels needles, show lower capacity of drag and extraction, and can potentially be related to more painful injection experience for patients.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inyecciones Subcutáneas , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Insulina , Dolor , Agujas
13.
Sensors (Basel) ; 23(4)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36850582

RESUMEN

The aim of this study was to determine a gait pattern, i.e., a subset of spatial and temporal parameters, through a supervised machine learning (ML) approach, which could be used to reliably distinguish Parkinson's Disease (PD) patients with and without mild cognitive impairment (MCI). Thus, 80 PD patients underwent gait analysis and spatial-temporal parameters were acquired in three different conditions (normal gait, motor dual task and cognitive dual task). Statistical analysis was performed to investigate the data and, then, five ML algorithms and the wrapper method were implemented: Decision Tree (DT), Random Forest (RF), Naïve Bayes (NB), Support Vector Machine (SVM) and K-Nearest Neighbour (KNN). First, the algorithms for classifying PD patients with MCI were trained and validated on an internal dataset (sixty patients) and, then, the performance was tested by using an external dataset (twenty patients). Specificity, sensitivity, precision, accuracy and area under the receiver operating characteristic curve were calculated. SVM and RF showed the best performance and detected MCI with an accuracy of over 80.0%. The key features emerging from this study are stance phase, mean velocity, step length and cycle length; moreover, the major number of features selected by the wrapper belonged to the cognitive dual task, thus, supporting the close relationship between gait dysfunction and MCI in PD.


Asunto(s)
Disfunción Cognitiva , Enfermedad de Parkinson , Humanos , Teorema de Bayes , Enfermedad de Parkinson/diagnóstico , Marcha , Análisis de la Marcha , Disfunción Cognitiva/diagnóstico
14.
Reprod Med Biol ; 22(1): e12542, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37795044

RESUMEN

Purpose: Here, we report, for the first time, the temporal expression and localization of axonemal radial spoke head homolog A (RSPH6A) protein during the first wave of rat spermatogenesis and in oxidative stress conditions. Methods: For the developmental study, testes were collected from rats at different developmental stages (7, 14, 21, 28, 35, 42, and 60 postnatal days); for in vivo treatment, 24 rats were treated with cadmium and/or melatonin. From each sample, western blot (WB) and immunofluorescence (IF) analyses for RSPH6A were performed. Results: RSPH6A expression starts at 21 PND alongside the appearance of I spermatocytes (SPC) with a significant increase up to 60 PND. Data were confirmed by IF analysis, showing that RPSH6A expression is restricted to I and II SPC, spermatids, and mature sperm. In vivo experiments showed that the expression and localization of RSPH6A in the testis and epididymal spermatozoa of adult rats treated with cadmium were impaired. Interestingly, melatonin (an antioxidant), given together with Cd, can counteract its damaging effects. Conclusions: All combined data confirm that RSPH6A contributes to the onset of fertility by acting on sperm motility, raising the possibility of using RSPH6A as a marker for normal fertility in the general population.

15.
EMBO J ; 37(21)2018 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-30237313

RESUMEN

ABC transporters utilize ATP for export processes to provide cellular resistance against toxins, antibiotics, and harmful metabolites in eukaryotes and prokaryotes. Based on static structure snapshots, it is believed that they use an alternating access mechanism, which couples conformational changes to ATP binding (outward-open conformation) and hydrolysis (inward-open) for unidirectional transport driven by ATP Here, we analyzed the conformational states and dynamics of the antibacterial peptide exporter McjD from Escherichia coli using single-molecule Förster resonance energy transfer (smFRET). For the first time, we established smFRET for an ABC exporter in a native-like lipid environment and directly monitor conformational dynamics in both the transmembrane- (TMD) and nucleotide-binding domains (NBD). With this, we unravel the ligand dependences that drive conformational changes in both domains. Furthermore, we observe intrinsic conformational dynamics in the absence of ATP and ligand in the NBDs. ATP binding and hydrolysis on the other hand can be observed via NBD conformational dynamics. We believe that the progress made here in combination with future studies will facilitate full understanding of ABC transport cycles.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/química , Adenosina Trifosfato/química , Proteínas de Escherichia coli/química , Escherichia coli/química , Transferencia Resonante de Energía de Fluorescencia , Simulación de Dinámica Molecular , Dominios Proteicos
16.
N Engl J Med ; 380(9): 833-841, 2019 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-30763140

RESUMEN

BACKGROUND: Central centrifugal cicatricial alopecia (CCCA) is the most common form of scarring alopecia among women of African ancestry. The disease is occasionally observed to affect women in families in a manner that suggests an autosomal dominant trait and usually manifests clinically after intense hair grooming. We sought to determine whether there exists a genetic basis of CCCA and, if so, what it is. METHODS: We used exome sequencing in a group of women with alopecia (discovery set), compared the results with those in a public repository, and applied other filtering criteria to identify candidate genes. We then performed direct sequencing to identify disease-associated DNA variations and RNA sequencing, protein modeling, immunofluorescence staining, immunoblotting, and an enzymatic assay to evaluate the consequences of potential etiologic mutations. We used a replication set that consisted of women with CCCA to confirm the data obtained with the discovery set. RESULTS: In the discovery set, which included 16 patients, we identified one splice site and three heterozygous missense mutations in PADI3 in 5 patients (31%). (The approximate prevalence of the disease is up to 5.6%.) PADI3 encodes peptidyl arginine deiminase, type III (PADI3), an enzyme that post-translationally modifies other proteins that are essential to hair-shaft formation. All three CCCA-associated missense mutations in PADI3 affect highly conserved residues and are predicted to be pathogenic; protein modeling suggests that they result in protein misfolding. These mutations were found to result in reduced PADI3 expression, abnormal intracellular localization of the protein, and decreased enzymatic activity - findings that support their pathogenicity. Immunofluorescence staining showed decreased expression of PADI3 in biopsy samples of scalp skin obtained from patients with CCCA. We then directly sequenced PADI3 in an additional 42 patients (replication set) and observed genetic variants in 9 of them. A post hoc analysis of the combined data sets showed that the prevalence of PADI3 mutation was higher among patients with CCCA than in a control cohort of women of African ancestry (P = 0.002 by the chi-square test; P = 0.006 by Fisher's exact test; and after adjustment for relatedness of persons, P = 0.03 and P = 0.04, respectively). CONCLUSIONS: Mutations in PADI3, which encodes a protein that is essential to proper hair-shaft formation, were associated with CCCA. (Funded by the Ram Family Foundation and others.).


Asunto(s)
Alopecia/genética , Negro o Afroamericano/genética , Predisposición Genética a la Enfermedad , Cabello/crecimiento & desarrollo , Mutación , Desiminasas de la Arginina Proteica/genética , Adolescente , Adulto , Edad de Inicio , Alopecia/etnología , Distribución de Chi-Cuadrado , Cicatriz/genética , Exoma , Femenino , Heterocigoto , Humanos , Persona de Mediana Edad , Mutagénesis , Linaje , Arginina Deiminasa Proteína-Tipo 3 , Desiminasas de la Arginina Proteica/metabolismo , Cuero Cabelludo/patología , Análisis de Secuencia de ADN
17.
Br J Dermatol ; 187(6): 962-969, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35861701

RESUMEN

BACKGROUND: Cutaneous immune-related adverse events (irAEs) represent the most frequent toxicities induced by immune checkpoint inhibitors (ICIs). OBJECTIVES: To investigate clinical associations of cutaneous toxicities induced by different ICI therapies. METHODS: This was a multicentre retrospective international cohort study of patients with cancer who developed cutaneous irAEs under ICI therapy. Analysis was performed of the rates and basic characteristics of all cutaneous toxicities, and identification of any associations was performed using univariate and multivariate models. RESULTS: In total, 762 patients were included, who developed 993 cutaneous toxicities. Forty different types of skin toxicities were identified. Psoriasis (175 patients, 23·0%) and pruritus (171 patients, 22·4%) were the most common toxicities, followed by macular rash (161 patients, 21·1%) and eczematous-type reactions (150 patients, 19·7%). Multivariate analysis showed that among patients with macular rash, vitiligo or multiple toxicities, patients received ICIs more frequently for melanoma than for NSCLC. Moreover, anti-CTLA4 was less frequent than anti-programmed death 1 treatment in patients with macular rash [odds ratio (OR) 0·11, 95% confidence interval (CI) 0·01-0·76] and vitiligo (OR 0·07, 95% CI 0·006-0·78). A significant association was also seen in patients treated with a combination of ICI and chemotherapy vs. ICI monotherapy. They less frequently developed psoriasis (OR 0·08, 95% CI 0·02-0·31), lichenoid reactions (OR 0·15, 95% CI 0·03-0·77) and eczematous reactions (OR 0·24, 95% CI 0·07-0·78), all compared with pruritic rash. CONCLUSIONS: Our study showed that skin-oriented toxicities do not share a single pattern and are related to several factors, including the specific agent administered and the underlying malignancy treated. Follow-up plans should be individualized in order to minimize the risk for severe reactions that could compromise optimum therapeutic outcome. What is already known about this topic? Patients with cancer treated with different immune checkpoint inhibitors (ICIs) carry an increased risk of developing various types of skin toxicities. What are the clinical implications of this work? In this multicentre cohort study we showed that ICI-related skin toxicities do not share a single pattern and may depend on several factors, including the specific agent administered and the underlying malignancy. Among patients with macular rash, vitiligo or multiple skin toxicities, patients received ICIs more frequently for melanoma than for non-small cell lung cancer. The combination of ICI and chemotherapy compared with ICI monotherapy occurred to a lesser extent in patients with psoriatic rash lichenoid and eczematous reactions, compared with patients with pruritus. Clinical awareness and specialized dermatological consultation should be advocated.


Asunto(s)
Antineoplásicos Inmunológicos , Carcinoma de Pulmón de Células no Pequeñas , Dermatología , Exantema , Neoplasias Pulmonares , Melanoma , Neoplasias , Psoriasis , Venereología , Vitíligo , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Estudios Retrospectivos , Vitíligo/inducido químicamente , Estudios de Cohortes , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neoplasias/inducido químicamente , Melanoma/tratamiento farmacológico , Melanoma/inducido químicamente , Exantema/inducido químicamente , Psoriasis/tratamiento farmacológico , Psoriasis/inducido químicamente , Prurito/tratamiento farmacológico
18.
Acta Psychiatr Scand ; 145(1): 42-55, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34510423

RESUMEN

OBJECTIVE: To evaluate whether accelerated brain aging occurs in individuals with mood or psychotic disorders. METHODS: A systematic review following PRISMA guidelines was conducted. A meta-analysis was then performed to assess neuroimaging-derived brain age gap in three independent groups: (1) schizophrenia and first-episode psychosis, (2) major depressive disorder, and (3) bipolar disorder. RESULTS: A total of 18 papers were included. The random-effects model meta-analysis showed a significantly increased neuroimaging-derived brain age gap relative to age-matched controls for the three major psychiatric disorders, with schizophrenia (3.08; 95%CI [2.32; 3.85]; p < 0.01) presenting the largest effect, followed by bipolar disorder (1.93; [0.53; 3.34]; p < 0.01) and major depressive disorder (1.12; [0.41; 1.83]; p < 0.01). The brain age gap was larger in older compared to younger individuals. CONCLUSION: Individuals with mood and psychotic disorders may undergo a process of accelerated brain aging reflected in patterns captured by neuroimaging data. The brain age gap tends to be more pronounced in older individuals, indicating a possible cumulative biological effect of illness burden.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo Mayor , Trastornos Psicóticos , Esquizofrenia , Anciano , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/epidemiología , Encéfalo/diagnóstico por imagen , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/epidemiología , Humanos , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/epidemiología , Esquizofrenia/diagnóstico por imagen
19.
Clin Exp Rheumatol ; 40(6): 1065-1072, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35748720

RESUMEN

Fibromyalgia syndrome (FM) is a chronic widespread pain syndrome characterised by fatigue, sleep disturbances and many idiopathic pain symptoms. The aim of this review is to describe and summarise the most recent findings concerning the diagnosis, aetiopathogenesis and treatment of fibromyalgia syndrome published between January 2021 and January 2022 and appearing on PubMed database. In particular, last year's literature focused on the impact of COVID-19 pandemic on FM patients, on new aetiopathogenetic horizons and the last conclusions about pharmacological and non-pharmacological interventions.


Asunto(s)
COVID-19 , Dolor Crónico , Fibromialgia , Fatiga/complicaciones , Fibromialgia/diagnóstico , Fibromialgia/epidemiología , Fibromialgia/etiología , Humanos , Pandemias
20.
BMC Med Inform Decis Mak ; 22(1): 141, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35610697

RESUMEN

BACKGROUND: The rapid growth in the complexity of services and stringent quality requirements present a challenge to all healthcare facilities, especially from an economic perspective. The goal is to implement different strategies that allows to enhance and obtain health processes closer to standards. The Length Of Stay (LOS) is a very useful parameter for the management of services within the hospital and is an index evaluated for the management of costs. In fact, a patient's LOS can be affected by a number of factors, including their particular condition, medical history, or medical needs. To reduce and better manage the LOS it is necessary to be able to predict this value. METHODS: In this study, a predictive model was built for the total LOS of patients undergoing laparoscopic appendectomy, one of the most common emergency procedures. Demographic and clinical data of the 357 patients admitted at "San Giovanni di Dio e Ruggi d'Aragona" University Hospital of Salerno (Italy) had used as independent variable of the multiple linear regression model. RESULTS: The obtained model had an R2 value of 0.570 and, among the independent variables, the significant variables that most influence the total LOS were Age, Pre-operative LOS, Presence of Complication and Complicated diagnosis. CONCLUSION: This work designed an effective and automated strategy for improving the prediction of LOS, that can be useful for enhancing the preoperative pathways. In this way it is possible to characterize the demand and to be able to estimate a priori the occupation of the beds and other related hospital resources.


Asunto(s)
Apendicectomía , Laparoscopía , Apendicectomía/métodos , Hospitalización , Hospitales , Humanos , Tiempo de Internación , Estudios Retrospectivos
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