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1.
Front Artif Intell ; 7: 1377337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716361

RESUMO

This study aims at addressing the challenging incremental few-shot object detection (iFSOD) problem toward online adaptive detection. iFSOD targets to learn novel categories in a sequential manner, and eventually, the detection is performed on all learned categories. Moreover, only a few training samples are available for all sequential novel classes in these situations. In this study, we propose an efficient yet suitably simple framework, Expandable-RCNN, as a solution for the iFSOD problem, which allows online sequentially adding new classes with zero retraining of the base network. We achieve this by adapting the Faster R-CNN to the few-shot learning scenario with two elegant components to effectively address the overfitting and category bias. First, an IOU-aware weight imprinting strategy is proposed to directly determine the classifier weights for incremental novel classes and the background class, which is with zero training to avoid the notorious overfitting issue in few-shot learning. Second, since the above zero-retraining imprinting approach may lead to undesired category bias in the classifier, we develop a bias correction module for iFSOD, named the group soft-max layer (GSL), that efficiently calibrates the biased prediction of the imprinted classifier to organically improve classification performance for the few-shot classes, preventing catastrophic forgetting. Extensive experiments on MS-COCO show that our method can significantly outperform the state-of-the-art method ONCE by 5.9 points in commonly encountered few-shot classes.

2.
Hum Brain Mapp ; 45(6): e26651, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38646963

RESUMO

Humans regularly assess the quality of their judgements, which helps them adjust their behaviours. Metacognition is the ability to accurately evaluate one's own judgements, and it is assessed by comparing objective task performance with subjective confidence report in perceptual decisions. However, for preferential decisions, assessing metacognition in preference-based decisions is difficult because it depends on subjective goals rather than the objective criterion. Here, we develop a new index that integrates choice, reaction time, and confidence report to quantify trial-by-trial metacognitive sensitivity in preference judgements. We found that the dorsomedial prefrontal cortex (dmPFC) and the right anterior insular were more activated when participants made bad metacognitive evaluations. Our study suggests a crucial role of the dmPFC-insula network in representing online metacognitive sensitivity in preferential decisions.


Assuntos
Mapeamento Encefálico , Tomada de Decisões , Imageamento por Ressonância Magnética , Metacognição , Humanos , Metacognição/fisiologia , Masculino , Feminino , Adulto Jovem , Tomada de Decisões/fisiologia , Adulto , Tempo de Reação/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Julgamento/fisiologia , Córtex Cerebral/fisiologia , Córtex Cerebral/diagnóstico por imagem , Comportamento de Escolha/fisiologia
3.
Materials (Basel) ; 17(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38255491

RESUMO

In recent years, much work related to the performance of AlSi10Mg manufactured by selective laser melting (SLM) has been extensively researched. However, the study of tribological performance caused by different laser energy densities is still insufficient. This work concentrates on the relationship between the wear resistance and laser energy density of AlSi10Mg processed using SLM. Moreover, XRD characterization, density, surface roughness and microhardness were also examined since they are closely related to wear resistance. The results revealed that the XRD pattern of AlSi10Mg was mainly composed of the α-Al and Si phases under the conditions of different laser energy densities. In addition, the peak of Mg2Si was also detected. Also, the grain size increased with the increasing of laser energy density. The increase in laser energy density led to an increase in the convection and porous phenomenon in the molten pool. However, when the value was lower, the overlapping area reduced, and the strength between adjacent melting paths was insufficient, resulting in the declination of the sample property. According to the experimental results, a laser energy density of 63.33 J/mm3 was considered to be a relative optimal condition. The relative density, Ra, microhardness and wear volume were 99.2%, 8.86 µm, 128.3 HV0.2 and 2.96 × 10-2 mm3, respectively. The worn surface morphology also confirmed the influence of laser energy density on wear resistance. A regression model was established and analyzed, which showed the reliability of the results. Furthermore, the tribological mechanism was also revealed.

4.
Zootaxa ; 5399(4): 327-346, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38221151

RESUMO

The Cosmococcus species (Hemiptera: Coccomorpha: Lecanodiaspididae) found in China are reviewed. Based on morphological and molecular data, C. albizziae Borchsenius, 1960 syn. nov. and C. euphorbiae Borchsenius, 1959 syn. nov. are placed as junior synonyms of C. erythrinae Borchsenius, 1959. The wax tests of both sexes and the slide-mounted adult female of C. erythrinae Borchsenius are redescribed.


Assuntos
Hemípteros , Masculino , Feminino , Animais , China
5.
Eur J Pharm Biopharm ; 191: 166-174, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37673316

RESUMO

Hydrogen sulphide (H2S) is an important gaseous signalling molecule with emerging roles as a neuroprotectant. The objective of this study was to investigate the feasibility of transdermal delivery of mitochondrial-targeted H2S donor, AP39 whilst investigating the ability of permeated AP39 on abrogating 6-hydroxydopamine (6-OH-dop)-induced mitochondrial dysfunction, as a model of Parkinson's disease, established in human neuroblastoma cells, SHSY-5Y. Aqueous hypromellose gels (5% w/v) were prepared with up to 10% v/v propylene glycol (PG) with 0.002% w/w AP39. AP39 permeation from formulations across excised murine skin into PBS was quantified over 24 h using HPLC-UV detection. Media was collected and applied to a microvasculature blood-brain-barrier (BBB) model to evidence AP39 permeability. Following, the permeate was applied to neuroblastoma cells SHSY-5Y to evidence its therapeutic potential in modulating the mitochondrial bioenergetics and antioxidant in response to 6-OH-dop-induced mitochondrial dysfunction. The presence of PG in gel formulations significantly increased the cumulative amount of AP39 permeated across murine skin over 24 h from 24.40 ± 2.39 % to 48.59 ± 2.93 %. Conditioned media applied to a microvasculature BBB model observed AP39 permeation across the barrier and H2S release. Finally, permeated AP39 enhanced parameters of mitochondrial bioenergetics in SHSY-5Y exposed to 6-OH-dop. Moreover, permeated AP39 abrogated mitochondrial-specific reactive oxygen species generation induced by 6-OH-dop. These findings demonstrate transdermal delivery of AP39 may provide a promising alternative to deliver this mitochondrial-targeted H2S donor and this approach allows the potential to cross the BBB reaching CNS organs in the treatment of neurodegenerative conditions such as Parkinson's disease. Moreover, our observations show that gels prepared with 10% v/v PG have the potential for use in conditions requiring rapid H2S delivery whereas gels without PG have potential for therapy requiring sustained H2S delivery.

6.
Exp Eye Res ; 234: 109596, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37479075

RESUMO

Previous reports have demonstrated that defects in the spliceosome-associated protein CWC27 can lead to the degeneration of retinal cells in Cwc27 mutant mouse models. However, it is unknown whether gene replacement therapy can rescue this phenotype. The purpose of this study was to evaluate whether AAV based gene therapy could rescue the retinal degeneration observed in Cwc27 mutant mice. By 6 months of age, Cwc27 mutant mice show a retinal degenerative phenotype, including morphological and functional abnormalities, primarily driven by the death of photoreceptors. We hypothesize that subretinal injection of AAV8 to drive exogenous CWC27 protein expression will improve the retinal phenotype. We evaluated these improvements after gene therapy with electroretinography (ERG) and histology, either hematoxylin and eosin (H&E) or immunostaining. In this study, we demonstrated that subretinal injection of AAV8-GRK-Cwc27-FLAG in mutant mice can improve the functionality and morphology of the retina. Immunostaining analyses revealed a notable decrease in photoreceptor degeneration, including cone cell degeneration, in the AAV-injected eyes compared to the PBS-injected eyes. Based on these results, gene replacement therapy could be a promising method for treating retinal degeneration caused by mutations in Cwc27.


Assuntos
Degeneração Retiniana , Camundongos , Animais , Degeneração Retiniana/genética , Degeneração Retiniana/terapia , Degeneração Retiniana/metabolismo , Vetores Genéticos , Retina/metabolismo , Terapia Genética/métodos , Células Fotorreceptoras Retinianas Cones/metabolismo , Eletrorretinografia , Modelos Animais de Doenças
7.
Antioxidants (Basel) ; 12(3)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36978982

RESUMO

Endothelial dysfunction is implicated in the development and aggravation of cardiovascular complications. Among the endothelium-released vasoactive factors, hydrogen sulfide (H2S) has been investigated for its beneficial effects on the vasculature through anti-inflammatory and redox-modulating regulatory mechanisms. Reduced H2S bioavailability is reported in chronic diseases such as cardiovascular disease, diabetes, atherosclerosis and preeclampsia, suggesting the value of investigating mechanisms, by which H2S acts as a vasoprotective gasotransmitter. We explored whether the protective effects of H2S were linked to the mitochondrial health of endothelial cells and the mechanisms by which H2S rescues apoptosis. Here, we demonstrate that endothelial dysfunction induced by TNF-α increased endothelial oxidative stress and induced apoptosis via mitochondrial cytochrome c release and caspase activation over 24 h. TNF-α also affected mitochondrial morphology and altered the mitochondrial network. Post-treatment with the slow-releasing H2S donor, GYY4137, alleviated oxidising redox state, decreased pro-caspase 3 activity, and prevented endothelial apoptosis caused by TNF-α alone. In addition, exogenous GYY4137 enhanced S-sulfhydration of pro-caspase 3 and improved mitochondrial health in TNF-α exposed cells. These data provide new insights into molecular mechanisms for cytoprotective effects of H2S via the mitochondrial-driven pathway.

8.
bioRxiv ; 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36789417

RESUMO

Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined was subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY, and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads, and discordant read pairs. PCR followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. In total, sixteen candidate pathogenic SVs were identified in sixteen families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive, and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS, PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.

9.
Hum Mol Genet ; 32(12): 2005-2015, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-36811936

RESUMO

Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined were subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads and discordant read pairs. Polymerase Chain Reaction (PCR) followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. A total of 16 candidate pathogenic SVs were identified in 16 families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS and PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.


Assuntos
Doenças Retinianas , Humanos , Doenças Retinianas/genética , Mutação , Sequenciamento Completo do Genoma , Sequenciamento do Exoma , Alelos , Glicoproteínas de Membrana/genética , Chaperonas Moleculares/genética , Proteínas do Olho/genética
10.
Antioxidants (Basel) ; 11(11)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36358464

RESUMO

Hypoxia, or insufficient oxygen availability is a common feature in the development of a myriad of cardiovascular-related conditions including ischemic disease. Hydrogen sulphide (H2S) donors, such as sodium thiosulphate (STS), are known for their cardioprotective properties. However, H2S due to its gaseous nature, is released and cleared rapidly, limiting its potential translation to clinical settings. For the first time, we developed and characterised liposome formulations encapsulating STS and explored their potential for modulating STS uptake, H2S release and the ability to retain pro-angiogenic and biological signals in a hypoxia-like environment mirroring oxygen insufficiency in vitro. Liposomes were prepared by varying lipid ratios and characterised for size, polydispersity and charge. STS liposomal encapsulation was confirmed by HPLC-UV detection and STS uptake and H2S release was assessed in vitro. To mimic hypoxia, cobalt chloride (CoCl2) was administered in conjunction with formulated and non-formulated STS, to explore pro-angiogenic and metabolic signals. Optimised liposomal formulation observed a liposome diameter of 146.42 ± 7.34 nm, a polydispersity of 0.22 ± 0.19, and charge of 3.02 ± 1.44 mV, resulting in 25% STS encapsulation. Maximum STS uptake (76.96 ± 3.08%) from liposome encapsulated STS was determined at 24 h. Co-exposure with CoCl2 and liposome encapsulated STS resulted in increased vascular endothelial growth factor mRNA as well as protein expression, enhanced wound closure and increased capillary-like formation. Finally, liposomal STS reversed metabolic switch induced by hypoxia by enhancing mitochondrial bioenergetics. These novel findings provide evidence of a feasible controlled-delivery system for STS, thus H2S, using liposome-based nanoparticles. Likewise, data suggests that in scenarios of hypoxia, liposomal STS is a good therapeutic candidate to sustain pro-angiogenic signals and retain metabolic functions that might be impaired by limited oxygen and nutrient availability.

11.
Foods ; 11(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36140932

RESUMO

Grape volatile compounds directly determine the aroma quality of wines. Although the aroma profile of grapes evolved greatly at different maturity stages, there were less considerations for aroma status when determining grape harvest time. In the present study, several maturation indicators, namely, sugars/acids ratio, free volatile compounds, bound volatile compounds and IBMP (3-isobutyl-2-methoxypyrazine) content were monitored in four red wine grape varieties (Vitis vinifera L. cv Cabernet Sauvignon, Cabernet Gernischet, Cabernet Franc and Merlot) near harvest time (42 days) in Ningxia, China. The results showed that the highest sugars/acids ratio was reached on day 21 and day 28 for Merlot and the other three varieties, respectively. For both free and bound volatile compounds, the content of carbonyl compounds decreased continuously in the process of ripening. The contents of free alcohols, esters and terpenes increased in the ripening stage and decreased in the stage of over-ripening. The accumulation of favorable bound aroma compounds peaked at day 35. The content of IBMP presenting a green smell in all four varieties descended continuously and kept steady from day 28. Therefore, the present findings revealed that the best aroma maturity time of four studied grape varieties was later than the sugars/acids ratio in Ningxia region. Aroma maturity should be taken into account during harvest time determination.

12.
Pharm Res ; 39(2): 341-352, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35088236

RESUMO

PURPOSE: Hydrogen sulphide (H2S) is an important signalling molecule involved in the regulation of several physiological and pathophysiological processes. The objective of this study was to investigate the feasibility of transdermal delivery of ADT-OH, a H2S donor, by investigating the transdermal flux of aqueous gels loaded with penetration enhancers or liposomes. Furthermore, we explored the ability of permeated ADT-OH to promote angiogenesis and mitochondrial bioenergetics in HUVEC cells. METHODS: Aqueous hypromellose gels (5% w/v) were prepared with up to 10% v/v propylene glycol (PG) or deformable liposomes with 0.025% w/w ADT-OH. ADT-OH permeation from formulations across excised murine skin into PBS was quantified over 24 h using HPLC-UV detection. Media was collected and applied to HUVEC cells to evidence ADT-OH functionality following permeation. Tube formation assays were performed as indicative of angiogenesis and mitochondrial oxygen consumption was evaluated using a Seahorse XF24. RESULTS: Increasing the loading of PG caused an increase in ADT-OH permeation rate across skin and a decrease in dermal drug retention whereas liposomal gels produced a slow-release profile. Treatment of HUVEC's using conditioned media collected from the ADT-OH loaded permeation studies enhanced tube formation and the basal oxygen consumption rates after 30 min of treatment. CONCLUSIONS: These findings demonstrate that transdermal delivery of ADT-OH may provide a promising approach in the treatment of impaired vascular function. Gels prepared with 10% v/v PG have the potential for use in conditions requiring rapid H2S release whereas liposomal loaded gels for treatment requiring sustained H2S release.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Sulfeto de Hidrogênio/administração & dosagem , Absorção Cutânea , Tionas/administração & dosagem , Administração Cutânea , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Composição de Medicamentos , Metabolismo Energético/efeitos dos fármacos , Feminino , Géis , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Tionas/química , Tionas/metabolismo
13.
Hum Mol Genet ; 31(8): 1278-1292, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-34726245

RESUMO

Previous in vitro studies indicate that CWC27 functions as a splicing factor in the Bact spliceosome complex, interacting with CWC22 to form a landing platform for eIF4A3, a core component of the exon junction complex. However, the function of CWC27 as a splicing factor has not been validated in any in vivo systems. CWC27 variants have been shown to cause autosomal recessive retinal degeneration, in both syndromic and non-syndromic forms. The Cwc27K338fs/K338fs mouse model was shown to have significant retinal dysfunction and degeneration by 6 months of age. In this report, we have taken advantage of the Cwc27K338fs/K338fs mouse model to show that Cwc27 is involved in splicing in vivo in the context of the retina. Bulk RNA and single cell RNA-sequencing of the mouse retina showed that there were gene expression and splicing pattern changes, including alternative splice site usage and intron retention. Positive staining for CHOP suggests that ER stress may be activated in response to the splicing pattern changes and is a likely contributor to the disease mechanism. Our results provide the first evidence that CWC27 functions as a splicing factor in an in vivo context. The splicing defects and gene expression changes observed in the Cwc27K338fs/K338fs mouse retina provide insight to the potential disease mechanisms, paving the way for targeted therapeutic development.


Assuntos
Peptidilprolil Isomerase/metabolismo , Degeneração Retiniana , Processamento Alternativo/genética , Animais , Íntrons/genética , Camundongos , Sítios de Splice de RNA , Splicing de RNA/genética , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Spliceossomos/genética
14.
J Clin Med ; 12(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36614820

RESUMO

Objective: To investigate lactate dehydrogenase/Albumin to-urea (LAU) ratio as a potential predictor for COVID-19-induced fatal clinical complications in hospitalized patients. Methods: This is a retrospective study involving blood analyses from 1139 hospitalised COVID-19 infection survivors and 349 deceased cases post-COVID-19 infection. Laboratory tests included complete blood picture, inflammatory markers, and routine organ function tests. Results: The non-survivor group showed lower haemoglobin (p < 0.001), platelet (p < 0.0001) and higher mean corpuscular volume, neutrophil count, neutrophil/lymphocytes ratio (NLR), and LAU (p < 0.001, p < 0.0013, p < 0.001, p < 0.0126) than the patients who survived the infection. The non-survivors also exhibited higher markers for infection-related clinical complications, such as international normalized ratio (INR), D-dimer, urea, total bilirubin, alkaline phosphatase (ALK), creatinine, c-reactive protein (CRP), and serum ferritin levels (all p < 0.05). In addition, LAU ratio was positively correlated with infection prognostic parameters including INR (r = 0.171), D-dimer (r = 0.176), serum urea (r = 0.424), total bilirubin (r = 0.107), ALK (r = 0.115), creatinine (r = 0.365), CRP (r = 0.268), ferritin (r = 0.385) and negatively correlated with serum albumin (r = −0.114) (p ≤ 0.05). LAU ratio had an area under receiver operating characteristic of 0.67 compared to 0.60 with NLR. Conclusion: Patients with a high LAU ratio are at increased risk of mortality due to COVID-19 infection. Therefore, early assessment of this parameter, intensive intervention and close monitoring could improve their prognosis.

15.
Biol Chem ; 402(8): 887-909, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34218539

RESUMO

The placenta is a highly vascularized and complex foetal organ that performs various tasks, crucial to a healthy pregnancy. Its dysfunction leads to complications such as stillbirth, preeclampsia, and intrauterine growth restriction. The specific cause of placental dysfunction remains unknown. Recently, the role of mitochondrial function and mitochondrial adaptations in the context of angiogenesis and placental dysfunction is getting more attention. The required energy for placental remodelling, nutrient transport, hormone synthesis, and the reactive oxygen species leads to oxidative stress, stemming from mitochondria. Mitochondria adapt to environmental changes and have been shown to adjust their oxygen and nutrient use to best support placental angiogenesis and foetal development. Angiogenesis is the process by which blood vessels form and is essential for the delivery of nutrients to the body. This process is regulated by different factors, pro-angiogenic factors and anti-angiogenic factors, such as sFlt-1. Increased circulating sFlt-1 levels have been linked to different preeclamptic phenotypes. One of many effects of increased sFlt-1 levels, is the dysregulation of mitochondrial function. This review covers mitochondrial adaptations during placentation, the importance of the anti-angiogenic factor sFlt-1in placental dysfunction and its role in the dysregulation of mitochondrial function.


Assuntos
Placenta , Pré-Eclâmpsia , Feminino , Retardo do Crescimento Fetal , Humanos , Estresse Oxidativo , Gravidez , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
16.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065595

RESUMO

Angiogenesis is one of the main processes that coordinate the biological events leading to a successful pregnancy, and its imbalance characterizes several pregnancy-related diseases, including preeclampsia. Intracellular interactions via extracellular vesicles (EVs) contribute to pregnancy's physiology and pathophysiology, and to the fetal-maternal interaction. The present review outlines the implications of EV-mediated crosstalk in the angiogenic process in healthy pregnancy and its dysregulation in preeclampsia. In particular, the effect of EVs derived from gestational tissues in pro and anti-angiogenic processes in the physiological and pathological setting is described. Moreover, the application of EVs from placental stem cells in the clinical setting is reported.


Assuntos
Vesículas Extracelulares/patologia , Neovascularização Patológica/patologia , Placenta/patologia , Pré-Eclâmpsia/patologia , Animais , Feminino , Humanos , Gravidez
17.
Hum Mol Genet ; 30(21): 1907-1918, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34104971

RESUMO

Much of the complexity of the eukaryotic cell transcriptome is due to the alternative splicing of mRNA. However, knowledge on how transcriptome complexity is translated into functional complexity remains limited. For example, although different isoforms of a gene may show distinct temporal and spatial expression patterns, it is largely unknown whether these isoforms encode proteins with distinct functions matching their expression pattern. In this report, we investigated the function and relationship of the two isoforms of Reep6, namely Reep6.1 and Reep6.2, in rod photoreceptor cells. These two isoforms result from the alternative splicing of exon 5 and show mutually exclusive expression patterns. Reep6.2 is the canonical isoform that is expressed in non-retinal tissues, whereas Reep6.1 is the only expressed isoform in the adult retina. The Reep6.1 isoform-specific knockout mouse, Reep6E5/E5, is generated by deleting exon 5 and a homozygous deletion phenotypically displayed a rod degeneration phenotype comparable to a Reep6 full knockout mouse, indicating that the Reep6.1 isoform is essential for the rod photoreceptor cell survival. Consistent with the results obtained from a loss-of-function experiment, overexpression of Reep6.2 failed to rescue the rod degeneration phenotype of Reep6 knockout mice whereas overexpression of Reep6.1 does lead to rescue. These results demonstrate that, consistent with the expression pattern of the isoform, Reep6.1 has rod-specific functions that cannot be substituted by its canonical isoform. Our findings suggested that a strict regulation of splicing is required for the maintenance of photoreceptor cells.


Assuntos
Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Regulação da Expressão Gênica , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Retina/metabolismo , Processamento Alternativo , Animais , Córtex Cerebral/metabolismo , Eletrorretinografia , Imunofluorescência , Genótipo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Fenótipo , Células Fotorreceptoras de Vertebrados/metabolismo , Isoformas de Proteínas , RNA Mensageiro
18.
Mol Vis ; 27: 95-106, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907365

RESUMO

Purpose: Despite the extensive use of next-generation sequencing (NGS) technology to identify disease-causing genomic variations, a major gap in our understanding of Mendelian diseases is the unidentified molecular lesion in a significant portion of patients. For inherited retinal degenerations (IRDs), although currently close to 300 disease-associated genes have been identified, the mutations in approximately one-third of patients remain unknown. With mounting evidence that noncoding mutations might contribute significantly to disease burden, we aimed to systematically investigate the contributions of noncoding regions in the genome to IRDs. Methods: In this study, we focused on RPGRIP1, which has been linked to various IRD phenotypes, including Leber congenital amaurosis (LCA), retinitis pigmentosa (RP), and macular dystrophy (MD). As several noncoding mutant alleles have been reported in RPGRIP1, and we observed that the mutation carrier frequency of RPGRIP1 is higher in patient cohorts with unsolved IRDs, we hypothesized that mutations in the noncoding regions of RPGRIP1 might be a significant contributor to pathogenicity. To test this hypothesis, we performed whole-genome sequencing (WGS) for 25 patients with unassigned IRD who carry a single mutation in RPGRIP1. Results: Three noncoding variants in RPGRIP1, including a 2,890 bp deletion and two deep-intronic variants (c.2710+233G>A and c.1468-263G>C), were identified as putative second hits of RPGRIP1 in three patients with LCA. The mutant alleles were validated with direct sequencing or in vitro assays. Conclusions: The results highlight the significance of the contribution of noncoding pathogenic variants to unsolved IRD cases.


Assuntos
Proteínas do Citoesqueleto/genética , Mutação/genética , RNA não Traduzido/genética , Degeneração Retiniana/genética , Adulto , Alelos , Pré-Escolar , Clonagem Molecular , Eletrorretinografia , Feminino , Humanos , Masculino , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Retina/fisiopatologia , Degeneração Retiniana/diagnóstico , Degeneração Retiniana/fisiopatologia , Tomografia de Coerência Óptica , Transfecção , Acuidade Visual/fisiologia , Sequenciamento Completo do Genoma
19.
Front Genet ; 12: 647400, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33737949

RESUMO

High throughput sequencing technologies have revolutionized the identification of mutations responsible for a diverse set of Mendelian disorders, including inherited retinal disorders (IRDs). However, the causal mutations remain elusive for a significant proportion of patients. This may be partially due to pathogenic mutations located in non-coding regions, which are largely missed by capture sequencing targeting the coding regions. The advent of whole-genome sequencing (WGS) allows us to systematically detect non-coding variations. However, the interpretation of these variations remains a significant bottleneck. In this study, we investigated the contribution of deep-intronic splice variants to IRDs. WGS was performed for a cohort of 571 IRD patients who lack a confident molecular diagnosis, and potential deep intronic variants that affect proper splicing were identified using SpliceAI. A total of six deleterious deep intronic variants were identified in eight patients. An in vitro minigene system was applied to further validate the effect of these variants on the splicing pattern of the associated genes. The prediction scores assigned to splice-site disruption positively correlated with the impact of mutations on splicing, as those with lower prediction scores demonstrated partial splicing. Through this study, we estimated the contribution of deep-intronic splice mutations to unassigned IRD patients and leveraged in silico and in vitro methods to establish a framework for prioritizing deep intronic variant candidates for mechanistic and functional analyses.

20.
Foods ; 11(1)2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-35010148

RESUMO

The eastern foothills of the Helan Mountains in the Ningxia region (Ningxia), is a Chinese wine-producing region, where Cabernet Sauvignon is the main grape cultivar; however, little compositional or flavor information has been reported on Ningxia wines. Oenological parameters, volatile profiles, and phenolic profiles were determined for 98 Ningxia Cabernet Sauvignon wines from the 2013-2018 vintages, as well as 16 from Bordeaux and California, for comparison. Ningxia wines were characterized by high ethanol, low acidity, and high anthocyanin contents. Multivariate analysis revealed that citronellol and 12 characteristic phenolic compounds distinguish Ningxia wines from Bordeaux and California wines. The concentrations of most phenolic compounds were highest in the 2018 Ningxia vintage and decreased with the age of the vintage. To our knowledge, this is the first extensive regionality study on red wines from the Ningxia region.

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