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1.
Nat Immunol ; 25(10): 1959-1975, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39223350

RESUMO

Deciphering the composition of the tumor microenvironment (TME) is critical for understanding tumorigenesis and to design immunotherapies. In the present study, we mapped genetic effects on cell-type proportions using single-cell and bulk RNA sequencing data, identifying 3,494 immunity quantitative trait loci (immunQTLs) across 23 cancer types from The Cancer Genome Atlas. Functional annotation revealed regulatory potential and we further assigned 1,668 genes that regulate TME composition. We constructed a combined immunQTL map by integrating data from European and Chinese colorectal cancer (CRC) samples. A polygenic risk score that incorporates these immunQTLs and hits on a genome-wide association study outperformed in CRC risk stratification within 447,495 multiethnic individuals. Using large-scale population cohorts, we identified that the immunQTL rs1360948 is associated with CRC risk and prognosis. Mechanistically, the rs1360948-G-allele increases CCL2 expression, recruiting regulatory T cells that can exert immunosuppressive effects on CRC progression. Blocking the CCL2-CCR2 axis enhanced anti-programmed cell death protein 1 ligand therapy. Finally, we have established a database (CancerlmmunityQTL2) to serve the research community and advance our understanding of immunogenomic interactions in cancer pathogenesis.


Assuntos
Neoplasias Colorretais , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Receptores CCR2/genética , Receptores CCR2/metabolismo , Linfócitos T Reguladores/imunologia , Regulação Neoplásica da Expressão Gênica , Prognóstico , Animais , Camundongos , Predisposição Genética para Doença , Análise de Célula Única
2.
Exp Eye Res ; 244: 109931, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763353

RESUMO

Gene therapy is one of the strategies that may reduce or reverse progressive neurodegeneration in retinal neurodegenerative diseases. However, efficiently delivering transgenes to retinal ganglion cells (RGCs) remains hard to achieve. In this study, we innovatively investigated transduction efficiency of adeno-associated virus (AAV)-PHP.eB in murine RGCs by retro-orbital venous sinus injection. Five doses of AAV-PHP.eB-EGFP were retro-orbitally injected in venous sinus in adult C57/BL6J mice. Two weeks after administration, RGCs transduction efficiency was quantified by retinal flat-mounts and frozen section co-labeling with RGCs marker Rbpms. In addition, safety of this method was evaluated by RGCs survival rate and retinal morphology. To conform efficacy of this new method, AAV-PHP.eB-CNTF was administrated into mature mice through single retro-orbital venous injection after optic nerve crush injury to evaluate axonal elongation. Results indicated that AAV- PHP.eB readily crossed the blood-retina barrier and was able to transduce more than 90% of RGCs when total dose of virus reached 5 × 1010 vector genomes (vg). Moreover, this technique did not affect RGCs survival rate and retinal morphology. Furthermore, retro-orbital venous delivery of AAV-PHP.eB-CNTF effectively transduced RGCs, robustly promoted axonal regeneration after optic nerve crush injury. Thus, novel AAV-PHP.eB retro-orbital injection provides a minimally invasive and efficient route for transgene delivery in treatment of retinal neurodegenerative diseases.


Assuntos
Dependovirus , Terapia Genética , Vetores Genéticos , Camundongos Endogâmicos C57BL , Células Ganglionares da Retina , Transdução Genética , Animais , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/metabolismo , Camundongos , Dependovirus/genética , Terapia Genética/métodos , Traumatismos do Nervo Óptico/terapia , Traumatismos do Nervo Óptico/metabolismo , Modelos Animais de Doenças , Sobrevivência Celular , Órbita/irrigação sanguínea
3.
Sensors (Basel) ; 24(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38475167

RESUMO

The fast development of the sensors in the wireless sensor networks (WSN) brings a big challenge of low energy consumption requirements, and Peer-to-peer (P2P) communication becomes the important way to break this bottleneck. However, the interference caused by different sensors sharing the spectrum and the power limitations seriously constrains the improvement of WSN. Therefore, in this paper, we proposed a deep reinforcement learning-based energy consumption optimization for P2P communication in WSN. Specifically, P2P sensors (PUs) are considered agents to share the spectrum of authorized sensors (AUs). An authorized sensor has permission to access specific data or systems, while a P2P sensor directly communicates with other sensors without needing a central server. One involves permission, the other is direct communication between sensors. Each agent can control the power and select the resources to avoid interference. Moreover, we use a double deep Q network (DDQN) algorithm to help the agent learn more detailed features of the interference. Simulation results show that the proposed algorithm can obtain a higher performance than the deep Q network scheme and the traditional algorithm, which can effectively lower the energy consumption for P2P communication in WSN.

4.
Molecules ; 29(19)2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39407555

RESUMO

Dissolved gas analysis (DGA) is considered to be the most convenient and effective approach for transformer fault diagnosis. Due to their excellent performance and development potential, chemiresistive gas sensors are anticipated to supersede the traditional gas chromatography analysis in the dissolved gas analysis of transformers. However, their high operating temperature and high power consumption restrict their deployment in battery-powered devices. This review examines the underlying principles of chemiresistive gas sensors. It comprehensively summarizes recent advances in low-power gas sensors for the detection of dissolved fault characteristic gases (H2, C2H2, CH4, C2H6, C2H4, CO, and CO2). Emphasis is placed on the synthesis methods of sensitive materials and their properties. The investigations have yielded substantial experimental data, indicating that adjusting the particle size and morphology structure of the sensitive materials and combining them with noble metal doping are the principal methods for enhancing the sensitivity performance and reducing the power consumption of chemiresistive gas sensors. Additionally, strategies to overcome the significant challenge of cross-sensitivity encountered in applications are provided. Finally, the future development direction of chemiresistive gas sensors for DGA is envisioned, offering guidance for developing and applying novel gas-sensitive sensors in transformer fault diagnosis.

5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(1): 47-53, 2024 Jan 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38615165

RESUMO

Trigeminal neuralgia is a manifestation of orofacial neuropathic pain disorder, always deemed to be an insurmountable peak in the field of pain research and treatment. The pain is recurrent, abrupt in onset and termination similar to an electric shock or described as shooting. A poor quality of life has been attributed to trigeminal neuralgia, as the paroxysms of pain may be triggered by innocuous stimuli on the face or inside the oral cavity, such as talking, washing face, chewing and brushing teeth in daily life. The pathogenesis of trigeminal neuralgia has not been fully elucidated, although the microvascular compression in the trigeminal root entry zone is generally considered to be involved in the emergence and progression of the pain disorder. In addition, orofacial neuropathic pain restricted to one or more divisions of the trigeminal nerve might be secondary to peripheral nerve injury. Based on current hypotheses regarding the potential causes, a variety of animal models have been designed to simulate the pathogenesis of trigeminal neuralgia, including models of compression applied to the trigeminal nerve root or trigeminal ganglion, chronic peripheral nerve injury, peripheral inflammatory pain and center-induced pain. However, it has not yet been possible to determine which model can be perfectly employed to explain the mechanisms. The selection of appropriate animal models is of great significance for the study of trigeminal neuralgia. Therefore, it is necessary to discuss the characteristics of the animal models in terms of animal strains, materials, operation methods and behavior observation, in order to gain insight into the research progress in animal models of trigeminal neuralgia. In the future, animal models that closely resemble the features of human trigeminal neuralgia pathogenesis need to be developed, with the aim of making valuable contributions to the relevant basic and translational medical research.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Neuralgia do Trigêmeo , Animais , Humanos , Qualidade de Vida , Mastigação , Modelos Animais
6.
Int J Cancer ; 153(3): 499-511, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37087737

RESUMO

Previous investigations mainly focused on the associations of dietary fatty acids with colorectal cancer (CRC) risk, which ignored gene-environment interaction and mechanisms interpretation. We conducted a case-control study (751 cases and 3058 controls) and a prospective cohort study (125 021 participants) to explore the associations between dietary fatty acids, genetic risks, and CRC. Results showed that high intake of saturated fatty acid (SFA) was associated with a higher risk of CRC than low SFA intake (HR =1.22, 95% CI:1.02-1.46). Participants at high genetic risk had a greater risk of CRC with the HR of 2.48 (2.11-2.91) than those at low genetic risk. A multiplicative interaction of genetic risk and SFA intake with incident CRC risk was found (PInteraction = 7.59 × 10-20 ), demonstrating that participants with high genetic risk and high SFA intake had a 3.75-fold greater risk of CRC than those with low genetic risk and low SFA intake. Furthermore, incorporating PRS and SFA into traditional clinical risk factors improved the discriminatory accuracy for CRC risk stratification (AUC from 0.706 to 0.731). Multi-omics data showed that exposure to SFA-rich high-fat dietary (HFD) can responsively induce epigenome reprogramming of some oncogenes and pathological activation of fatty acid metabolism pathway, which may contribute to CRC development through changes in gut microbiomes, metabolites, and tumor-infiltrating immune cells. These findings suggest that individuals with high genetic risk of CRC may benefit from reducing SFA intake. The incorporation of SFA intake and PRS into traditional clinical risk factors will help improve high-risk sub-populations in individualized CRC prevention.


Assuntos
Neoplasias Colorretais , Gorduras na Dieta , Humanos , Estudos Prospectivos , Estudos de Casos e Controles , Gorduras na Dieta/efeitos adversos , Fatores de Risco , Ácidos Graxos/efeitos adversos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/induzido quimicamente
7.
Anal Chem ; 95(40): 14934-14943, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37752733

RESUMO

Methods to manipulate magnetic beads are essential factors to determine the efficiency and dimension of an in vitro diagnostic system. Currently, using movable permanent magnets and planar electromagnets is still the major approach to achieve magnetic bead control, causing significant constraint in the miniaturization of in vitro diagnostic systems. Here, we propose techniques to construct a fully integrated microfluidic device that can conduct automatic magnetic bead manipulation as well as rapid chemical reaction and cleaning in a minimized dimension similar to a USB disk. The device combines the precision control of multiple electromagnetic coils with the compactness of microfluidic channels, leading to one of the smallest automatic magnetic bead manipulation systems that can complete several major magnetic bead-based operation steps such as sample injection, reaction, cleaning, and collection. The influencing factors such as coil driving parameters, surface treatment of the microchannels, and properties of magnetic particles have also been investigated to optimize the device performance. The device can drive mixtures of Fe3O4 microparticles and polymer magnetic beads (PMBs) with a weight ratio of 1:1 at a maximum speed of 0.5 cm·s-1 and reduce the time for DNA binding and dissociation reactions from 20 min to only 48 s. This device has significantly advanced the conventional manipulation methods of magnetic beads and has demonstrated the possibility to construct an automatic and ultraminiaturized in vitro diagnostic system that may facilitate portable or even wearable chemical analysis.

8.
Mol Pharmacol ; 102(3): 161-171, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35764384

RESUMO

Sialic acid-binding Ig-like lectin-15 is an important immunosuppressive molecule considered to be a key target in next-generation tumor immunotherapy. In this study, we screened 22 high-affinity antibodies that specifically recognize human Siglec-15 by using a large human phage antibody library, and five representative sequences were selected for further study. The results showed the binding activity of five antibodies to Siglec-15 (EC50 ranged from 0.02368 µg/mL to 0.07949 µg/mL), and in two Siglec-15-overexpressed cell lines, three antibodies had the strongest binding activity, so the two clones were discarded for further study. Subsequently, the affinity of three antibodies were measured by bio-layer interferometry technology (5-9 × 10E-09M). As the reported ligands of Siglec-15, the binding activity of Siglec-15 and sialyl-Tn, cluster of differentiation 44, myelin-associated glycoprotein, and leucine-rich repeat-containing protein 4C can be blocked by three of the antibodies. Among these, 3F1 had a competitive advantage. Then, the antibody 3F1 showed an obvious antibody-dependent cell-mediated cytotoxicity effect (EC50 was 0.85 µg/mL). Further, antibody 3F1 can reverse the inhibitory effect of Siglec-15 on lymphocyte proliferation (especially CD4+T and CD8+T) and cytokine release Interferon-γ. Given the above results, 3F1 was selected as a candidate for the in vivo pharmacodynamics study. In the tumor model of Balb/c Nude mice, 3F1 (10 mg/kg) showed certain antitumor effects [tumor growth inhibition (TGI) was 31.5%], while the combination of 3F1 (5 mg/kg) and Erbitux (5 mg/kg) showed significant antitumor effects (TGI was 48.7%) compared with the PBS group. In conclusion, novel human antibody 3F1 has antitumor activity and is expected to be an innovative candidate drug targeting Siglec-15 for tumor immunotherapy. SIGNIFICANCE STATEMENT: Siglec-15 is considered as an important target in the next generation of tumor immunotherapy. 3F1 is expected to be the most promising potential candidate for targeting Siglec-15 for cancer treatment and could provide a reference for the development of antitumor drugs.


Assuntos
Antígenos CD , Neoplasias , Animais , Antígenos CD/metabolismo , Humanos , Imunoglobulinas , Lectinas/química , Lectinas/metabolismo , Ligantes , Proteínas de Membrana , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico
9.
BMC Genomics ; 23(1): 639, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076168

RESUMO

BACKGROUND: Sinosenecio B. Nordenstam (Asteraceae) currently comprises 44 species. To investigate the interspecific relationship, several chloroplast markers, including ndhC-trnV, rpl32-trnL, matK, and rbcL, are used to analyze the phylogeny of Sinosenecio. However, the chloroplast genomes of this genus have not been thoroughly investigated. We sequenced and assembled the Sinosenecio albonervius chloroplast genome for the first time. A detailed comparative analysis was performed in this study using the previously reported chloroplast genomes of three Sinosenecio species. RESULTS: The results showed that the chloroplast genomes of four Sinosenecio species exhibit a typical quadripartite structure. There are equal numbers of total genes, protein-coding genes and RNA genes among the annotated genomes. Per genome, 49-56 simple sequence repeats and 99 repeat sequences were identified. Thirty codons were identified as RSCU values greater than 1 in the chloroplast genome of S. albonervius based on 54 protein-coding genes, indicating that they showed biased usage. Among 18 protein-coding genes, 46 potential RNA editing sites were discovered. By comparing these chloroplast genomes' structures, inverted repeat regions and coding regions were more conserved than single-copy and non-coding regions. The junctions among inverted repeat and single-copy regions showed slight difference. Several hot spots of genomic divergence were detected, which can be used as new DNA barcodes for species identification. Phylogenetic analysis of the whole chloroplast genome showed that the four Sinosenecio species have close interspecific relationships. CONCLUSIONS: The complete chloroplast genome of Sinosenecio albonervius was revealed in this study, which included a comparison of Sinosenecio chloroplast genome structure, variation, and phylogenetic analysis for related species. These will help future research on Sinosenecio taxonomy, identification, origin, and evolution to some extent.


Assuntos
Asteraceae , Genoma de Cloroplastos , Asteraceae/genética , Cloroplastos/genética , Repetições de Microssatélites/genética , Filogenia
10.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743157

RESUMO

Traumatic optic neuropathy (TON) is a significant cause of vision loss and irreversible blindness worldwide. It is defined as retinal ganglion cell death and axon degeneration caused by injury. Optic nerve crush (ONC), a well-validated model of TON, activates retinal microglia and initiates neuroinflammation. High-mobility group box 1 (HMGB1), a non-histone chromosomal binding protein in the nucleus of eukaryotic cells, is an important inducer of microglial activation and pro-inflammatory cytokine release. The purpose of this study was to examine the protective effects and mechanism of the HMGB1 inhibitor BoxA to neuroinflammation-induced retinal ganglion cells (RGCs) damage in traumatic optic neuropathy. For that purpose, an optic nerve crush model was established in C57BL/6J mice at 10-12 weeks. Model mice received an intravitreal injection of PBS and the HMGB1 inhibitor BoxA. Our data demonstrated that HMGB1 expression increased after optic nerve crush. Retinal ganglion cell function and morphology were damaged, and retinal ganglion cell numbers were reduced after optic nerve crush. Intravitreal injection of BoxA after ONC can alleviate damage. Furthermore, BoxA reduced microglial activation and expression levels of nuclear factor κB (NF-kB), nucleotide-binding domain, leucine-rich repeat containing protein 3 (NLRP3), and apoptosis-associated speck-like protein containing a CARD (ASC) in experimental ONC mice. In summary, HMGB1 mediates NLRP3 inflammasome via NF-kB to participate in retinal inflammatory injury after ONC. Thus, intravitreal injection of BoxA has potential therapeutic benefits for the effective treatment of RGC death to prevent TON.


Assuntos
Proteína HMGB1 , Traumatismos do Nervo Óptico , Animais , Modelos Animais de Doenças , Proteína HMGB1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Compressão Nervosa , Doenças Neuroinflamatórias , Traumatismos do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/metabolismo , Células Ganglionares da Retina/metabolismo
11.
Nanotechnology ; 33(2)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34544066

RESUMO

Glucose oxidase-mediated starvation therapy that effectively cuts off energy supply holds great promise in cancer treatment. However, high glutathione (GSH) contents and anoxic conditions severely reduce therapy efficiency and cannot fully kill cancer cells. Herein, to resolve the above problem, this study constructed a biomimetic nanosystem based on nanreproo-MnO2with porous craspedia globose-like structure and high specific surface area, and it was further modified with dopamine and folic acid to guarantee good biocompatibility and selectivity toward cancer cells. This nanosystem responsively degraded and reacted with GSH and acid to regenerate O2, which significantly increased intracellular O2levels, accelerated glucose consumption, and improved starvation therapy efficiency. Moreover, anticancer drug of camptothecin was further loaded, and notably enhanced cancer growth inhibition was obtained at very low drug concentrations. Most importantly, this novel therapy could unprecedentedly inhibit cancer cell migration to a very low ratio of 19%, and detailed cell apoptosis analyses revealed late stage apoptosis contributed most to the good therapeutic effect. This work reported a new train of thought to improve starvation therapy in biomedicine, and provided a new strategy to design targeted nanocarrier to delivery mixed drugs to overcome the restriction of starvation therapy and develop new therapy patterns.


Assuntos
Antineoplásicos , Glucose Oxidase , Neoplasias/terapia , Oxigênio/metabolismo , Hipóxia Tumoral/efeitos dos fármacos , Células A549 , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomimética , Camptotecina/farmacocinética , Camptotecina/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Glucose Oxidase/farmacologia , Células HeLa , Humanos , Indóis/química , Compostos de Manganês/química , Nanopartículas Metálicas/química , Nanomedicina , Óxidos/química , Polímeros/química , Propriedades de Superfície
12.
BMC Microbiol ; 20(1): 281, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32928115

RESUMO

BACKGROUND: Acinetobacter baumannii has traditionally been considered an opportunistic pathogen with low virulence. In this study, we characterized the carbapenem-resistant hypervirulent A. baumannii (CR-hvAB) stains isolated from our hospital in mid-south region of China. RESULTS: Blood samples collected between January 2017 and May 2019 were used for virulence experiments and biofilm assays of individual carbapenem-resistant A. baumannii (CR-AB) strains, performed using a Galleria mellonella infection model and crystal violet staining method, respectively. CR-AB isolates that induced high mortality in the G. mellonella infection model were subjected to genotyping, susceptibility testing, and clinical data analysis, and the genetic characterization of these isolates was performed by whole-genome sequencing (WGS). Among the 109 CR-AB clinical strains, the survival rate of G. mellonella larvae infected with 7 (6.4%) CR-AB isolates (number of strains with mortality of 0, 10 and 20% was 4, 1, and 2, respectively), was significantly lower than that of A. baumannii ATCC 19606 (100.0%) and the remaining CR-AB isolates (> 80.0%). Consistent with these results, patients infected with these seven isolates had an average 7-day mortality rate of 42.9%, suggesting that the isolates were CR-hvAB. These seven isolates belonged to four sequence types (STs): ST457, ST195, ST369, and ST2088 (a new ST), and mainly ST457 (n = 4). The results of the biofilm study showed that eight strains had powerful biofilm ability (strong [n = 1] and moderate [n = 7] biofilm producers) including these seven CR-hvAB isolates. CONCLUSIONS: CR-hvAB isolates that induced a high mortality rate were cloned in our hospital, most of which belonged to ST457; thus, monitoring of these strains, particularly ST457, should be strengthened in the future. Meanwhile, A. baumannii, which was isolated from blood specimens and found to powerful biofilm-forming ability, is a probable hvAB isolate.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/patogenicidade , Carbapenêmicos/farmacologia , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/etiologia , Acinetobacter baumannii/isolamento & purificação , Adolescente , Adulto , Idoso , Animais , Antibacterianos/farmacologia , Biofilmes , Criança , China , Modelos Animais de Doenças , Farmacorresistência Bacteriana/genética , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mariposas/microbiologia , Filogenia , Virulência/genética , Adulto Jovem
13.
J Org Chem ; 85(5): 3894-3901, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32049530

RESUMO

A highly stereoselective Mannich reaction of α-amino acid derived azlactones with isatin-derived ketimines enabled by a chiral bifunctional squaramide organocatalyst is reported, affording α,ß-diamino acid derivatives bearing vicinal quaternary stereocenters in moderate to good yields (40-95%), moderate to excellent diastereoselectivities (3:1 → 20:1), and good to excellent enantioselectivities (66-97%). This reaction can be readily performed on gram scale, and the Mannich adduct could be easily converted to the corresponding α,ß-diamino ester via simple operations.

14.
Int J Mol Sci ; 21(5)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121304

RESUMO

Alzheimer's disease (AD) is the most common type of neurodegenerative disease. Its typical pathology consists of extracellular amyloid-ß (Aß) plaques and intracellular tau neurofibrillary tangles. Mutations in the APP, PSEN1, and PSEN2 genes increase Aß production and aggregation, and thus cause early onset or familial AD. Even with this strong genetic evidence, recent studies support AD to result from complex etiological alterations. Among them, aging is the strongest risk factor for the vast majority of AD cases: Sporadic late onset AD (LOAD). Accumulation of DNA damage is a well-established aging factor. In this regard, a large amount of evidence reveals DNA damage as a critical pathological cause of AD. Clinically, DNA damage is accumulated in brains of AD patients. Genetically, defects in DNA damage repair resulted from mutations in the BRAC1 and other DNA damage repair genes occur in AD brain and facilitate the pathogenesis. Abnormalities in DNA damage repair can be used as diagnostic biomarkers for AD. In this review, we discuss the association, the causative potential, and the biomarker values of DNA damage in AD pathogenesis.


Assuntos
Doença de Alzheimer/patologia , Dano ao DNA , Doença de Alzheimer/genética , Reparo do DNA/genética , Humanos , Modelos Biológicos , Neurogênese , Fatores de Risco
15.
BMC Ophthalmol ; 19(1): 204, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601186

RESUMO

BACKGROUND: The metabolic activity of retina is higher than other human tissues and is crucial to the vision. Cynomolgus macaques is widely used in ophthalmic disease research. The evaluation and comparison of macular and optic disc vascular circulation parameters between normal adult cynomolgus macaques and healthy adult humans using OCT-A can promote better use of nonhuman primate models in studies of ophthalmic vascular disease. METHODS: Twelve normal adult cynomolgus macaques with a mean age of 4.91 ± 0.43 years were studied for data collection. The macula of 28 adult healthy humans (14 males and 14 females), with a mean age of 25.11 ± 6.21 years and the optic discs of 9 adult healthy humans (4 males and 5 females) with a mean age of 28.56 ± 6.78 years were measured. The vessel density (VD) was measured using an RTVue XR with AngioVue. The scan sizes of the macular and optic discs were 3 × 3 mm and 4.5 × 4.5 mm, respectively. RESULTS: OCT-A can image the superficial and deep capillary plexuses and radial peripapillary capillary network. In RPC layer of the optic disc, the VD in the nasal quadrant was lower than the VD in the inferior temporal quadrant. Similarities and significant differences in VD between healthy humans and cynomolgus macaques were obtained using OCT-A. CONCLUSIONS: This study provides normal vascular parameters for adult cynomolgus macaques using OCT-A to help establish an optical parameter database for cynomolgus macaques and compare VD between healthy humans and cynomolgus macaques to promote choroid-retinopathy research. TRIAL REGISTRATION: Current Controlled Trials NCT03692169 , retrospectively registered on 26 sept 2018.


Assuntos
Angiofluoresceinografia/métodos , Disco Óptico/irrigação sanguínea , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Adulto , Animais , Feminino , Fundo de Olho , Humanos , Macaca fascicularis , Masculino , Modelos Animais , Valores de Referência
16.
Cell Physiol Biochem ; 47(5): 1898-1908, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29961067

RESUMO

BACKGROUND/AIMS: Mitochondria (MT) and mitochondrial DNA (mtDNA) show maternal inheritance in most eukaryotic organisms; the sperm mtDNA is usually delivered to the egg during fertilization and then rapidly eliminated to avoid heteroplasmy, which can affect embryogenesis. In our previous study, fertilization-delivered sperm mtDNA exhibited late elimination and transcriptional quiescence in cyprinid fish embryos. However, the mechanisms underlying elimination and transcriptional quiescence of paternal mtDNA are unclear. METHODS: Goldfish and zebrafish were used to investigate the fate of mtDNAs with different parental origins delivered by fertilization or microinjection in embryos. Goldfish MT from heart, liver and spermatozoa were microinjected into zebrafish zygotes, respectively. Specific PCR primers were designed so that the amplicons have different sizes to characterize goldfish and zebrafish cytb genes or their cDNAs. RESULTS: The MT injection-delivered paternal mtDNA from sperm, as well as those from the heart and liver, was capable of persistence and transcription until birth, in contrast to the disappearance and transcriptional quiescence at the heartbeat stage of fertilization-delivered sperm mtDNA. In addition, the exogenous MT-injected zebrafish embryos have normal morphology during embryonic development. CONCLUSIONS: The fate of paternal mtDNA in fishes is dependent on the delivery strategy rather than the MT source, suggesting that the presence of sperm factor(s) is responsible for elimination and transcriptional quiescence of fertilization-delivered sperm mtDNA. These findings provide insights into the mechanisms underlying paternal mtDNA fate and heteroplasmy in cyprinid fishes.


Assuntos
DNA Mitocondrial/metabolismo , Embrião não Mamífero/embriologia , Carpa Dourada/embriologia , Mitocôndrias/metabolismo , Peixe-Zebra/embriologia , Animais , DNA Mitocondrial/genética , Carpa Dourada/genética , Mitocôndrias/genética , Peixe-Zebra/genética
17.
Org Biomol Chem ; 15(36): 7513-7517, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28869260

RESUMO

An efficient [4 + 3] annulation of 2-(1-tosylalkyl)phenols with C,N-cyclic azomethine imines via in situ generation of ortho-quinone methides (o-QMs) under mild basic reaction conditions is disclosed, furnishing biologically interesting seven-membered heterocyclic compounds with moderate to good yields and excellent diastereoselectivities. A gram-scale reaction is performed to demonstrate the potential in industrial application and two transition states are proposed to rationalize the outstanding diastereoselectivity.

18.
Mitochondrial DNA B Resour ; 9(1): 204-208, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38288251

RESUMO

The genus Sinosenecio B. Nordenstam is a group of perennial or sometimes annual or biennial herbs in the family Asteraceae. Here, we have successfully assembled and characterized the complete chloroplast (cp) genome of S. globigerus, which shows a typical quadratic structure with an overall GC content of 37.4%, comprising a pair of inverted repeat regions (IRs) of 24,848 bp, a large single-copy region (LSC) of 83,379 bp and a small single-copy region (SSC) of 18,180 bp. 133 genes were annotated, including 88 protein-coding genes, 37 tRNA genes and eight rRNA genes. Further nucleotide diversity analysis indicated that three genomic regions (accD-psaI, trnK-rps16, and ycf1) exhibited sufficient variability and thus could be recommended as valuable barcodes for the delimitation and identification of Sinosenecio species. Phylogenetic reconstruction presented clear interspecific relationships within Sinosenecio, which were supported to some extent by cytology, morphology and geographic distributions. Our study will provide valuable and high-quality genetic information to further elucidate the diversified mechanisms in Sinosenecio.

19.
Exp Anim ; 73(1): 20-28, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37460311

RESUMO

Nonhuman primates are important research models for basic vision research, preclinical pathogenesis, and treatment studies due to strong similarities in retinal structure and function with humans. We compared retinal parameters between 10 healthy normal rhesus macaques (Macaca mulatta) and 10 cynomolgus macaques (Macaca fascicularis) by optical coherence tomography and electroretinography. The Heidelberg Spectralis® HRA+OCT and Roland multifocal electrophysiometer were used to analyze retinal morphology, multifocal electroretinograms (mfERGs), and full-field electroretinograms (ff-ERGs). Mean retinal thickness was lowest in the central fovea of macaques and did not differ significantly between species, but the retinal thicknesses of the nerve fiber ganglion cell layer and the inner plexiform layer were significantly different. The amplitude density of the N1 wave was lower in rhesus macaques than in cynomolgus macaques in ring and quadrant areas. Dark-adapted 3.0 oscillatory potentials (reflection of amacrine cell activity) and light-adapted 30-hz flicker ERG (a sensitive cone-pathway-driven response) waveforms of the ff-ERG were similar in both species, while the times to peaks in dark-adapted 0.01 ERG (the rod-driven response of bipolar cells) and dark-adapted 3.0 ERG (combined rod and cone system responses) as well as the implicit times of the a- and b-waves in light-adapted 3.0 ERG (the single-flash cone response) were substantially different. This study provides normative retinal parameters for nonhuman primate research on basic and clinical ophthalmology, as well as a reference for researchers in the appropriate selection of rhesus or cynomolgus macaques as models for ophthalmology studies.


Assuntos
Eletrorretinografia , Retina , Humanos , Animais , Macaca mulatta , Macaca fascicularis , Retina/fisiologia , Eletrorretinografia/métodos , Neurônios
20.
Front Microbiol ; 15: 1361927, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495509

RESUMO

Background: In recent investigations, substantial strides have been made in the precise modulation of the gut microbiota to prevent and treat a myriad of diseases. Simultaneously, the pressing issue of widespread antibiotic resistance and multidrug resistance resulting from Shigella infections demands urgent attention. Several studies suggest that the antagonistic influence of the gut microbiota could serve as a novel avenue for impeding the colonization of pathogenic microorganisms or treating Shigella infections. However, conventional research methodologies encounter inherent challenges in identifying antagonistic microbial agents against Shigella, necessitating a comprehensive and in-depth analysis of the causal relationship between Shigella infections and the gut microbiota. Materials and methods: Utilizing the aggregated summary statistics from Genome-Wide Association Studies (GWAS), we conducted Mendelian Randomization (MR) analyses encompassing 18,340 participants to explore the interplay between the gut microbiota and Shigella infections. This investigation also involved 83 cases of Shigella infection patients and 336,396 control subjects. In the positive strand of our findings, we initially performed a preliminary analysis using the Inverse Variance Weighting (IVW) method. Subsequently, we undertook sensitivity analyses to assess the robustness of the results, addressing confounding factors' influence. This involved employing the Leave-One-Out method and scrutinizing funnel plots to ensure the reliability of the MR analysis outcomes. Conclusively, a reverse MR analysis was carried out, employing the Wald ratio method due to the exposure of individual Single Nucleotide Polymorphisms (SNPs). This was undertaken to explore the plausible associations between Shigella infections and genetically predicted compositions of the gut microbiota. Results: In this study, we employed 2,818 SNPs associated with 211 species of gut microbiota as instrumental variables (IVs). Through IVW analysis, our positive MR findings revealed a significant negative correlation between the occurrence of Shigella infections and the phylum Tenericutes (OR: 0.18, 95% CI: 0.04-0.74, p = 0.02), class Mollicutes (OR: 0.18, 95% CI: 0.04-0.74, p = 0.02), genus Intestinimonas (OR: 0.16, 95% CI: 0.04-0.63, p = 0.01), genus Gordonibacter (OR: 0.39, 95% CI: 0.16-0.93, p = 0.03), and genus Butyrivibrio (OR: 0.44, 95% CI: 0.23-0.87, p = 0.02). Conversely, a positive correlation was observed between the occurrence of Shigella infections and genus Sutterella (OR: 10.16, 95% CI: 1.87-55.13, p = 0.01) and genus Alistipes (OR: 12.24, 95% CI: 1.71-87.34, p = 0.01). In sensitivity analyses, utilizing MR-Egger regression analysis and MR Pleiotropy Residual Sum and Outlier (MR-PRESSO) detection, all outcomes demonstrated robust stability. Simultaneously, in the reverse MR analysis, Shigella infections resulted in an upregulation of four bacterial genera and a downregulation of three bacterial genera. Conclusion: In summation, the MR analysis outcomes corroborate the presence of bidirectional causal relationships between the gut microbiota and Shigella infections. This study not only unveils novel perspectives for the prevention and treatment of Shigella infections but also furnishes fresh insights into the mechanistic underpinnings of how the gut microbiota contributes to the pathogenesis of Shigella infections. Consequently, the established dual causal association holds promise for advancing our understanding and addressing the complexities inherent in the interplay between the gut microbiota and Shigella infections, thereby paving the way for innovative therapeutic interventions and preventive strategies in the realm of Shigella-related diseases.

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