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1.
Immunity ; 54(8): 1772-1787.e9, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34289378

RESUMO

As substantial constituents of the multiple myeloma (MM) microenvironment, pro-inflammatory macrophages have emerged as key promoters of disease progression, bone destruction, and immune impairment. We identify beta-2-microglobulin (ß2m) as a driver in initiating inflammation in myeloma-associated macrophages (MAMs). Lysosomal accumulation of phagocytosed ß2m promotes ß2m amyloid aggregation in MAMs, resulting in lysosomal rupture and ultimately production of active interleukin-1ß (IL-1ß) and IL-18. This process depends on activation of the NLRP3 inflammasome after ß2m accumulation, as macrophages from NLRP3-deficient mice lack efficient ß2m-induced IL-1ß production. Moreover, depletion or silencing of ß2m in MM cells abrogates inflammasome activation in a murine MM model. Finally, we demonstrate that disruption of NLRP3 or IL-18 diminishes tumor growth and osteolytic bone destruction normally promoted by ß2m-induced inflammasome signaling. Our results provide mechanistic evidence for ß2m's role as an NLRP3 inflammasome activator during MM pathogenesis. Moreover, inhibition of NLRP3 represents a potential therapeutic approach in MM.


Assuntos
Amiloide/metabolismo , Mieloma Múltiplo/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Macrófagos Associados a Tumor/metabolismo , Microglobulina beta-2/metabolismo , Animais , Células Cultivadas , Humanos , Inflamação/imunologia , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Lisossomos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Fagocitose/imunologia , Transdução de Sinais/imunologia , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Microglobulina beta-2/genética
2.
PLoS Genet ; 19(6): e1010797, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37307272

RESUMO

Transposable elements (TE) are mobile DNA sequences whose excessive proliferation endangers the host. Although animals have evolved robust TE-targeting defenses, including Piwi-interacting (pi)RNAs, retrotransposon LINE-1 (L1) still thrives in humans and mice. To gain insights into L1 endurance, we characterized L1 Bodies (LBs) and ORF1p complexes in germ cells of piRNA-deficient Maelstrom null mice. We report that ORF1p interacts with TE RNAs, genic mRNAs, and stress granule proteins, consistent with earlier studies. We also show that ORF1p associates with the CCR4-NOT deadenylation complex and PRKRA, a Protein Kinase R factor. Despite ORF1p interactions with these negative regulators of RNA expression, the stability and translation of LB-localized mRNAs remain unchanged. To scrutinize these findings, we studied the effects of PRKRA on L1 in cultured cells and showed that it elevates ORF1p levels and L1 retrotransposition. These results suggest that ORF1p-driven condensates promote L1 propagation, without affecting the metabolism of endogenous RNAs.


Assuntos
Retroelementos , Ribonucleoproteínas , Humanos , Masculino , Camundongos , Animais , Retroelementos/genética , Ribonucleoproteínas/genética , RNA de Interação com Piwi , Espermatócitos/metabolismo , Elementos Nucleotídeos Longos e Dispersos/genética , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
3.
Hum Mol Genet ; 31(15): 2535-2547, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35220430

RESUMO

Epidermal development and maintenance are finely regulated events requiring a strict balance between proliferation and differentiation. Alterations in these processes give rise to human disorders such as cancer or syndromes with skin and annexes defects, known as ectodermal dysplasias (EDs). Here, we studied the functional effects of two novel receptor-interacting protein kinase 4 (RIPK4) missense mutations identified in siblings with an autosomal recessive ED with cutaneous syndactyly, palmoplantar hyperkeratosis and orofacial synechiae. Clinical overlap with distinct EDs caused by mutations in transcription factors (i.e. p63 and interferon regulatory factor 6, IRF6) or nectin adhesion molecules was noticed. Impaired activity of the RIPK4 kinase resulted both in altered epithelial differentiation and defective cell adhesion. We showed that mutant RIPK4 resulted in loss of PVRL4/nectin-4 expression in patient epidermis and primary keratinocytes, and demonstrated that PVRL4 is transcriptionally regulated by IRF6, a RIPK4 phosphorylation target. In addition, defective RIPK4 altered desmosome morphology through modulation of plakophilin-1 and desmoplakin. In conclusion, this work implicates RIPK4 kinase function in the p63-IRF6 regulatory loop that controls the proliferation/differentiation switch and cell adhesion, with implications in ectodermal development and cancer.


Assuntos
Displasia Ectodérmica , Fatores Reguladores de Interferon , Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Displasia Ectodérmica/metabolismo , Homeostase , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Queratinócitos/metabolismo , Nectinas , Proteínas Serina-Treonina Quinases
4.
Anal Bioanal Chem ; 416(10): 2553-2564, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38459965

RESUMO

Crocin-I, a valuable natural compound found in saffron (Crocus sativus L.), is the most abundant among the various crocin structures. Developing a cost-effective and scalable purification process to produce high-purity crocin-I is of great interest for future investigations into its biological properties and its potential applications in the treatment of neurological disorders. However purifying crocin-I through single-column preparative chromatography (batch) poses a yield-purity trade-off due to structural similarities among crocins, meaning that the choice of the collection window sacrifices either yield in benefit of higher purity or vice versa. This study demonstrates how the continuous countercurrent operating mode resolves this dilemma. Herein, a twin-column MCSGP (multicolumn countercurrent solvent gradient purification) process was employed to purify crocin-I. This study involved an environmentally friendly ethanolic extraction of saffron stigma, followed by an investigation into the stability of the crocin-I within the feed under varying storage conditions to ensure a stable feed composition during the purification. Then, the batch purification process was initially designed, optimized, and subsequently followed by the scale-up to the MCSGP process. To ensure a fair comparison, both processes were evaluated under similar conditions (e.g., similar total column volume). The results showed that, at a purity grade of 99.7%, the MCSGP technique demonstrated significant results, namely + 334% increase in recovery + 307% increase in productivity, and - 92% reduction in solvent consumption. To make the purification process even greener, the only organic solvent employed was ethanol, without the addition of any additive. In conclusion, this study presents the MCSGP as a reliable, simple, and economical technique for purifying crocin-I from saffron extract, demonstrating for the first time that it can be effectively applied as a powerful approach for process intensification in the purification of natural products from complex matrices.


Assuntos
Distribuição Contracorrente , Crocus , Distribuição Contracorrente/métodos , Solventes/química , Carotenoides/química , Etanol/química
5.
Anal Bioanal Chem ; 416(8): 1809-1820, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38358532

RESUMO

The existence of slow adsorption-desorption kinetics in chiral liquid chromatography is common knowledge. This may significantly contribute to worsening the efficiency and kinetic performance of a chromatographic run, especially when high flow rates are employed. Many attempts and protocols have been proposed to access this term, the so-called c ads , but they are based on different (theoretical) assumptions. As a consequence, no official method is available for the estimation of the adsorption-desorption kinetics term. In this work, a novel approach to access c ads is presented. This procedure combines experimental results obtained with kinetic and thermodynamic measurements. The investigations have been performed on two zwitterionic teicoplanin chiral stationary phases (CSPs) based on 1.9 µ m fully porous and 2.0 µ m superficially porous particles (FPPs and SPPs), using Z-D,L-Methionine as probe molecule. Kinetic studies have been performed through the combination of both stop-flow and dynamic measurements, while adsorption isotherms have been calculated through Inverse Method. This study has confirmed that, on both particle formats, analyte diffusion on the surface of the particle is negligible, meaning that adsorption is localized, and it has been demonstrated that adsorption-desorption kinetics is strongly dependent on particle geometry and, in particular, on the loading of chiral selector. These findings are fundamental not only to unravel novel aspects of the complex enantiorecognition mechanism but also to optimize the employment of CSPs for ultra-fast and preparative applications.

6.
Anal Bioanal Chem ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748248

RESUMO

In the present study, twin-column recycling chromatography has been employed for the purification of a Cannabis extract by using a green solvent, ethanol, as the mobile phase. In particular, the complete removal of the psychoactive tetrahydrocannabinol (THC) from a Cannabis extract rich in cannabidiol (CBD) was achieved under continuous conditions. The performance of the method, in terms of compound purity, recovery, productivity and solvent consumption, was compared to that of traditional batch operations showing the potential of the twin-column recycling approach. The employment of a theoretical model to predict the band profiles of the two compounds during the recycling process has facilitated method development, thus further contributing to process sustainability by avoiding trial and error attempts or at least decreasing the number of steps significantly.

7.
Anal Bioanal Chem ; 416(16): 3797-3809, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38702447

RESUMO

The increasing interest in hemp and cannabis poses new questions about the influence of drying and storage conditions on the overall aroma and cannabinoids profile of these products. Cannabis inflorescences are subjected to drying shortly after harvest and then to storage in different containers. These steps may cause a process of rapid deterioration with consequent changes in precious secondary metabolite content, negatively impacting on the product quality and potency. In this context, in this work, the investigation of the effects of freeze vs tray drying and three storage conditions on the preservation of cannabis compounds has been performed. A multi-trait approach, combining both solid-phase microextraction (SPME) two-dimensional gas chromatography coupled to mass spectrometry (SPME-GC × GC-MS) and high-performance liquid chromatography (HPLC), is presented for the first time. This approach has permitted to obtain the detailed characterisation of the whole cannabis matrix in terms of volatile compounds and cannabinoids. Moreover, multivariate statistical analyses were performed on the obtained data, helping to show that freeze drying conditions is useful to preserve cannabinoid content, preventing decarboxylation of acid cannabinoids, but leads to a loss of volatile compounds which are responsible for the cannabis aroma. Furthermore, among storage conditions, storage in glass bottle seems more beneficial for the retention of the initial VOC profile compared to open to air dry tray and closed high-density polyethylene box. However, the glass bottle storage condition causes formation of neutral cannabinoids at the expenses of the highly priced acid forms. This work will contribute to help define optimal storage conditions useful to produce highly valuable and high-quality products.


Assuntos
Canabinoides , Cannabis , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Cannabis/química , Canabinoides/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Cromatografia Líquida de Alta Pressão/métodos , Inflorescência/química , Liofilização/métodos , Dessecação/métodos
8.
Anal Chem ; 95(25): 9630-9637, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37294639

RESUMO

The retention behavior of small molecules and N-protected amino acids on a zwitterionic teicoplanin chiral stationary phase (CSP), prepared on superficially porous particles (SPPs) of 2.0 µm particle diameter, has shown that efficiency and enantioselectivity, and so enantioresolution, dramatically change depending on the employed organic modifier. In particular, it was found that while methanol permits the boost of enantioselectivity and resolution of the amino acids, at the cost of efficiency, acetonitrile allows for the ability to reach extraordinary efficiency even at high flow rates (with reduced plate height <2 and up to 300,000 plates/m at the optimum flow rate). To understand these features, an approach based on the investigation of mass transfer through the CSP, the estimation of the binding constants of amino acids on the CSP, and the assessment of compositional properties of the interfacial region between bulk mobile phase and solid surface has been adopted.

9.
Pediatr Res ; 94(5): 1789-1796, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37344544

RESUMO

BACKGROUND: Despite multifactorial pathogenesis, dysregulation of inflammatory immune response may play a crucial role in necrotizing enterocolitis (NEC). Regulatory T cells (Tregs) are involved in immune tolerance early in life. We aimed to investigate the predicting role of Tregs in developing NEC in neonates at high risk. METHODS: We studied six newborns with a diagnosis of NEC (cases) in comparison with 52 controls (without NEC). We further classified controls as neonates with feeding intolerance (FI) and neonates without it (FeedTol). The rate of female and male neonates (sex defined as a biological attribute) was similar. We analyzed the blood frequency of Tregs (not overall numbers) at three time points: 0-3 (T0), 7-10 (T1), and 27-30 (T2) days after birth by flow cytometry. Neonates' sex was defined based on the inspection of external genitalia at birth. RESULTS: We observed, at T0, a significantly lower frequency of Tregs in NEC cases (p < 0.001) compared with both FI (p < 0.01) and FeedTol controls (p < 0.01). Multivariate analysis reported that the occurrence of NEC was independently influenced by Treg frequency at birth (ß 2.98; p = 0.039). CONCLUSION: Tregs frequency and features in the peripheral blood of preterm neonates, early in life, may contribute to identifying neonates at high risk of developing NEC. IMPACT: Regulatory T cells may play a pivotal role in regulating the immune response in early life. Reduction of Tregs in early life could predispose preterm newborns to necrotizing enterocolitis. Early markers of necrotizing enterocolitis are still lacking. We demonstrated a predicting role of assessment of regulatory T cells in the diagnosis of this gastrointestinal emergency. Early identification of newborns at high risk of necrotizing enterocolitis through measurement of regulatory T cells may guide clinicians in the management of preterm newborns in order to reduce the development of this severe condition.


Assuntos
Enterocolite Necrosante , Doenças Fetais , Doenças do Recém-Nascido , Recém-Nascido , Masculino , Humanos , Feminino , Enterocolite Necrosante/diagnóstico , Enterocolite Necrosante/epidemiologia , Recém-Nascido Prematuro , Linfócitos T Reguladores
10.
Anal Bioanal Chem ; 415(13): 2343-2355, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36650250

RESUMO

One convenient strategy to reduce environmental impact and pollution involves the reuse and revalorization of waste produced by modern society. Nowadays, global plastic production has reached 367 million tons per year and because of their durable nature, their recycling is fundamental for the achievement of the circular economy objective. In closing the loop of plastics, advanced recycling, i.e., the breakdown of plastics into their building blocks and their transformation into valuable secondary raw materials, is a promising management option for post-consumer plastic waste. The most valuable product from advanced recycling is a fluid hydrocarbon stream (or pyrolysis oil) which represents the feedstock for further refinement and processing into new plastics. In this context, gas chromatography is currently playing an important role since it is being used to study the pyrolysis oils, as well as any organic contaminants, and it can be considered a high-resolution separation technique, able to provide the molecular composition of such complex samples. This information significantly helps to tailor the pyrolysis process to produce high-quality feedstocks. In addition, the detection of contaminants (i.e., heteroatom-containing compounds) is crucial to avoid catalytic deterioration and to implement and design further purification processes. The current review highlights the importance of molecular characterization of waste stream products, and particularly the pyrolysis oils obtained from waste plastics. An overview of relevant applications published recently will be provided, and the potential of comprehensive two-dimensional gas chromatography, which represents the natural evolution of gas chromatography into a higher-resolution technique, will be underlined.

11.
Genet Med ; 24(2): 439-453, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34906501

RESUMO

PURPOSE: This study aimed to describe a multisystemic disorder featuring cardiovascular, facial, musculoskeletal, and cutaneous anomalies caused by heterozygous loss-of-function variants in TAB2. METHODS: Affected individuals were analyzed by next-generation technologies and genomic array. The presumed loss-of-function effect of identified variants was assessed by luciferase assay in cells transiently expressing TAB2 deleterious alleles. In available patients' fibroblasts, variant pathogenicity was further explored by immunoblot and osteoblast differentiation assays. The transcriptomic profile of fibroblasts was investigated by RNA sequencing. RESULTS: A total of 11 individuals from 8 families were heterozygotes for a novel TAB2 variant. In total, 7 variants were predicted to be null alleles and 1 was a missense change. An additional subject was heterozygous for a 52 kb microdeletion involving TAB2 exons 1 to 3. Luciferase assay indicated a decreased transcriptional activation mediated by NF-κB signaling for all point variants. Immunoblot analysis showed a reduction of TAK1 phosphorylation while osteoblast differentiation was impaired. Transcriptomic analysis identified deregulation of multiple pleiotropic pathways, such as TGFß-, Ras-MAPK-, and Wnt-signaling networks. CONCLUSION: Our data defined a novel disorder associated with loss-of-function or, more rarely, hypomorphic alleles in a restricted linker region of TAB2. The pleiotropic manifestations in this disorder partly recapitulate the 6q25.1 (TAB2) microdeletion syndrome and deserve the definition of cardio-facial-cutaneous-articular syndrome.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , NF-kappa B , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Éxons/genética , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Fosforilação , Transdução de Sinais
12.
Ann Neurol ; 89(4): 828-833, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33443317

RESUMO

The Mediator multiprotein complex functions as a regulator of RNA polymerase II-catalyzed gene transcription. In this study, exome sequencing detected biallelic putative disease-causing variants in MED27, encoding Mediator complex subunit 27, in 16 patients from 11 families with a novel neurodevelopmental syndrome. Patient phenotypes are highly homogeneous, including global developmental delay, intellectual disability, axial hypotonia with distal spasticity, dystonic movements, and cerebellar hypoplasia. Seizures and cataracts were noted in severely affected individuals. Identification of multiple patients with biallelic MED27 variants supports the critical role of MED27 in normal human neural development, particularly for the cerebellum. ANN NEUROL 2021;89:828-833.


Assuntos
Cerebelo/anormalidades , Deficiências do Desenvolvimento/genética , Distonia/genética , Complexo Mediador/genética , Malformações do Sistema Nervoso/genética , Adolescente , Adulto , Sequência de Aminoácidos , Catarata/genética , Criança , Pré-Escolar , Epilepsia/genética , Variação Genética , Humanos , Lactente , Fenótipo , Sequenciamento do Exoma
13.
PLoS Comput Biol ; 17(6): e1009045, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34181642

RESUMO

The brain exhibits capabilities of fast incremental learning from few noisy examples, as well as the ability to associate similar memories in autonomously-created categories and to combine contextual hints with sensory perceptions. Together with sleep, these mechanisms are thought to be key components of many high-level cognitive functions. Yet, little is known about the underlying processes and the specific roles of different brain states. In this work, we exploited the combination of context and perception in a thalamo-cortical model based on a soft winner-take-all circuit of excitatory and inhibitory spiking neurons. After calibrating this model to express awake and deep-sleep states with features comparable with biological measures, we demonstrate the model capability of fast incremental learning from few examples, its resilience when proposed with noisy perceptions and contextual signals, and an improvement in visual classification after sleep due to induced synaptic homeostasis and association of similar memories.


Assuntos
Potenciais de Ação , Córtex Cerebral/fisiologia , Modelos Neurológicos , Sono REM/fisiologia , Tálamo/fisiologia , Algoritmos , Córtex Cerebral/citologia , Homeostase , Humanos , Aprendizagem , Neurônios/fisiologia , Sinapses/fisiologia , Tálamo/citologia
14.
Anal Bioanal Chem ; 414(18): 5385-5395, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35146546

RESUMO

This work reports about a screening of four adsorbents with different polarity employed for the separation of the main phytocannabinoids contained in Cannabis sativa L., under normal phase liquid chromatography (NPLC). The effect of polarity and type of interaction mechanisms of the adsorbents (namely Si-, CN-, Diol-, and NH2-based SPs) on retention has been investigated under a variety of conditions either by using different combinations of apolar solvents (heptane or hexane) and alcohols (ethanol or isopropanol). The columns have also been employed for the separation of a real cannabis sample. Graphical Abstract Investigating the effect of polarity of stationary and mobile phases on retention of cannabinoids in normal phase liquid chromatography.


Assuntos
Canabinoides , Cannabis , Álcoois , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Solventes/química
16.
Am J Med Genet A ; 185(7): 2160-2163, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33844462

RESUMO

CHARGE syndrome is a rare genetic multiple-malformation disorder characterized by wide phenotypic variability. It is often caused by heterozygous variants in CHD7 and, more rarely, SEMA3E. Although craniofacial alterations are frequent in this condition, to date craniosynostosis is not considered part of the clinical spectrum. Here, we report bi-coronal craniosynostosis in a newborn affected by CHARGE syndrome caused by the de novo heterozygous c.6157C>T, p.(Arg2053*) CHD7 variant. We found two additional subjects in the literature with different craniosynostoses and distinct CHD7 alterations. The inclusion of CHD7-related CHARGE syndrome in the group of rare causes of syndromic craniosynostoses is proposed.


Assuntos
Síndrome CHARGE/genética , Craniossinostoses/genética , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Síndrome CHARGE/patologia , Craniossinostoses/patologia , Feminino , Heterozigoto , Humanos , Recém-Nascido , Mutação , Fenótipo , Semaforinas/genética
17.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298941

RESUMO

Clinical research aiming at objectively identifying and characterizing diseases via clinical observations and biological and radiological findings is a critical initial research step when establishing objective diagnostic criteria and treatments. Failure to first define such diagnostic criteria may lead research on pathogenesis and etiology to serious confounding biases and erroneous medical interpretations. This is particularly the case for electrohypersensitivity (EHS) and more particularly for the so-called "provocation tests", which do not investigate the causal origin of EHS but rather the EHS-associated particular environmental intolerance state with hypersensitivity to man-made electromagnetic fields (EMF). However, because those tests depend on multiple EMF-associated physical and biological parameters and have been conducted in patients without having first defined EHS objectively and/or endpoints adequately, they cannot presently be considered to be valid pathogenesis research methodologies. Consequently, the negative results obtained by these tests do not preclude a role of EMF exposure as a symptomatic trigger in EHS patients. Moreover, there is no proof that EHS symptoms or EHS itself are caused by psychosomatic or nocebo effects. This international consensus report pleads for the acknowledgement of EHS as a distinct neuropathological disorder and for its inclusion in the WHO International Classification of Diseases.


Assuntos
Biomarcadores/metabolismo , Hipersensibilidade/metabolismo , Sensibilidade Química Múltipla/metabolismo , Animais , Consenso , Diagnóstico por Imagem/métodos , Testes Diagnósticos de Rotina/métodos , Campos Eletromagnéticos , Humanos , Doenças do Sistema Nervoso/metabolismo
18.
Molecules ; 26(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361839

RESUMO

The market of biomolecules with therapeutic scopes, including peptides, is continuously expanding. The interest towards this class of pharmaceuticals is stimulated by the broad range of bioactivities that peptides can trigger in the human body. The main production methods to obtain peptides are enzymatic hydrolysis, microbial fermentation, recombinant approach and, especially, chemical synthesis. None of these methods, however, produce exclusively the target product. Other species represent impurities that, for safety and pharmaceutical quality reasons, must be removed. The remarkable production volumes of peptide mixtures have generated a strong interest towards the purification procedures, particularly due to their relevant impact on the manufacturing costs. The purification method of choice is mainly preparative liquid chromatography, because of its flexibility, which allows one to choose case-by-case the experimental conditions that most suitably fit that particular purification problem. Different modes of chromatography that can cover almost every separation case are reviewed in this article. Additionally, an outlook to a very recent continuous chromatographic process (namely Multicolumn Countercurrent Solvent Gradient Purification, MCSGP) and future perspectives regarding purification strategies will be considered at the end of this review.


Assuntos
Peptídeos/química , Peptídeos/síntese química , Peptídeos/isolamento & purificação , Cromatografia Líquida , Humanos , Peptídeos/uso terapêutico
19.
Br Med Bull ; 133(1): 36-48, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32043524

RESUMO

BACKGROUND: Intellectual disability (ID) affects 1-3% of the Western population and is heterogeneous in origin. Mutations in X-linked genes represent 5-10% of ID in males. Fragile X syndrome, due to the silencing of the FMR1 gene, is the most common form of ID, with a prevalence of around 1:5000 males. Females are usually non- or mildly affected carriers, and in a few rare cases, the only gender affected. Array comparative genome hybridization (aCGH) and next-generation sequencing (NGS) have dramatically changed the nature of human genome analysis leading to the identification of new X-linked intellectual disability syndromes and disease-causing genes. SOURCES OF DATA: Original papers, reviews, guidelines and experiences of the diagnostic laboratories. AREAS OF AGREEMENT: Family history and clinical examination still are essential to choose the appropriate diagnostic tests, including, a disease-specific genetic test, aCGH or FMR1 molecular analysis. If negative, NGS approaches like well-defined gene panels, whole exome, or even whole genome sequencing, are increasingly being used, improving diagnostics and leading to the identification of novel disease mechanisms. AREAS OF CONTROVERSY: The main challenge in the era of NGS is filtering and interpretation of the data generated by the analysis of a single individual. In X-linked cases, assessing pathogenicity is particularly challenging, even more when the variant is found to be inherited from a healthy carrier mother or when a heterozygous X-linked mutation is found in an impaired female. GROWING POINTS: At present, variant interpretation remains a challenging task, especially in X-linked disorders. We review the main difficulties and propose a comprehensive overview that might aid in variant interpretation. Establishing a genetic diagnosis facilitates counseling and allows better delineation of clinical phenotypes. AREAS TIMELY FOR DEVELOPING RESEARCH: To improve variant interpretation, there is need to refine in silico predictions with specific criteria for each gene, and to develop cost-effective functional tools, which can be easily transferred to diagnostics.


Assuntos
Deficiência Intelectual , Transtornos dos Cromossomos Sexuais , Hibridização Genômica Comparativa/métodos , Aconselhamento Genético/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Deficiência Intelectual/classificação , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Seleção de Pacientes , Transtornos dos Cromossomos Sexuais/classificação , Transtornos dos Cromossomos Sexuais/diagnóstico , Transtornos dos Cromossomos Sexuais/genética
20.
Clin Genet ; 98(5): 423-432, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32333401

RESUMO

Proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome (PVHH, OMIM 225790), also known as Fowler syndrome, is a rare autosomal recessive disorder of brain angiogenesis. PVHH has long been considered to be prenatally lethal. We evaluated the phenotypes of the first three siblings with survival into adulthood, performed a systematic review of the Fowler syndrome literature and delineated genotype-phenotype correlations using a scoring system to rate the severity of the disease. Thirty articles were included, describing 69 individual patients. To date, including our clinical reports, 72 patients have been described with Fowler syndrome. Only 6/72 (8%) survived beyond birth. Although our three patients carry the same mutations (c.327T>A-p.Asn109Lys and c.887C>T-p.Ser296Leu) in FLVCR2, only two of them presented with the same cerebral features, ventriculomegaly and cerebral calcifications, as affected fetuses. The third sibling has a surprisingly milder clinical and radiological phenotype, suggesting intrafamilial variability. Although no clear phenotype-genotype correlation exists, some variants appear to be associated with a less severe phenotype compatible with life. As such, it is important to consider Fowler syndrome in patients with gross ventriculomegaly, cortical malformations and/or cerebral calcifications on brain imaging.


Assuntos
Hidranencefalia/genética , Proteínas de Membrana Transportadoras/genética , Neovascularização Patológica/genética , Receptores Virais/genética , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Associação Genética , Humanos , Hidranencefalia/patologia , Mutação/genética , Neovascularização Patológica/patologia , Fenótipo
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