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1.
Proc Natl Acad Sci U S A ; 119(30): e2205068119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35857876

RESUMO

Bifidobacterium is a commensal bacterial genus ubiquitous in the human gastrointestinal tract, which is associated with a range of health benefits. The advent of CRISPR-based genome editing technologies provides opportunities to investigate the genetics of important bacteria and transcend the lack of genetic tools in bifidobacteria to study the basis for their health-promoting attributes. Here, we repurpose the endogenous type I-G CRISPR-Cas system and adopt an exogenous CRISPR base editor for genome engineering in B. animalis subsp. lactis, demonstrating that both genomic and epigenetic contexts drive editing outcomes across strains. We reprogrammed the endogenous type I-G system to screen for naturally occurring large deletions up to 27 kb and to generate a 500-bp deletion in tetW to abolish tetracycline resistance. A CRISPR-cytosine base editor was optimized to install C•G-to-T•A amber mutations to resensitize multiple B. lactis strains to tetracycline. Remarkably, we uncovered epigenetic patterns that are distributed unevenly among B. lactis strains, despite their genomic homogeneity, that may contribute to editing efficiency variability. Insights were also expanded to Bifidobacterium longum subsp. infantis to emphasize the broad relevance of these findings. This study highlights the need to develop individualized CRISPR-based genome engineering approaches for distinct bacterial strains and opens avenues for engineering of next generation probiotics.


Assuntos
Bifidobacterium , Sistemas CRISPR-Cas , Edição de Genes , Probióticos , Bifidobacterium/genética , Edição de Genes/métodos , Genoma Bacteriano/genética , Genômica , Humanos
2.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338938

RESUMO

It is well known that proteins are important bio-macromolecules in human organisms, and numerous proteins are widely used in the clinical practice, whereas their application in forensic science is currently limited. This limitation is mainly attributed to the postmortem degradation of targeted proteins, which can significantly impact final conclusions. In the last decade, numerous methods have been established to detect the protein from a forensic perspective, and some of the postmortem proteins have been applied in forensic practice. To better understand the emerging issues and challenges in postmortem proteins, we have reviewed the current application of protein technologies at postmortem in forensic practice. Meanwhile, we discuss the application of proteins in identifying the cause of death, and postmortem interval (PMI). Finally, we highlight the interpretability and limitations of postmortem protein challenges. We believe that utilizing the multi-omics method can enhance the comprehensiveness of applying proteins in forensic practice.


Assuntos
Mudanças Depois da Morte , Humanos , Proteólise , Causas de Morte , Patologia Legal , Autopsia
3.
Forensic Sci Med Pathol ; 20(1): 212-218, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37306888

RESUMO

Thoracic aortic dissection (TAD) is an important cause of sudden cardiac death and is characterized by high morbidity, mortality, and a poor prognosis. Patent ductus arteriosus (PDA) is a common congenital heart disease. The pathogenesis of both TAD and PDA has been reported to be related to genetic factors. The MYH11 gene, which encodes myosin heavy chain 11, has been reported in individuals with both TAD and PDA. Herein, we first detected a harmful MYH11 missense variant (c. T3728C, p. L1243P) in a TAD and PDA family. This missense variant co-segregated with the TAD/PDA phenotype in this family of four individuals, providing evidence of its harmfulness. Histopathological examinations revealed the presence of fragmented, broken, and lessened elastic fibers and the deposition of proteoglycans in the median of aortic dissection. Moreover, the immunofluorescence results showed that the labeled MYH11 protein in the tissue of the aortic dissection was weaker than that in the normal aorta. We present this familial case to stress the necessity of postmortem genetic testing in such cases among forensic practices. Identifying those culprit gene variants can direct effective genetic counseling and personalized health management in family members (especially first-degree relatives) with high-risk genotypes.


Assuntos
Dissecção Aórtica , Dissecção da Aorta Torácica , Permeabilidade do Canal Arterial , Humanos , Permeabilidade do Canal Arterial/genética , Permeabilidade do Canal Arterial/patologia , Testes Genéticos , Dissecção Aórtica/genética , Aorta/patologia , Cadeias Pesadas de Miosina/genética
4.
Anal Chem ; 95(25): 9598-9604, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37311025

RESUMO

5-Methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are two of the most abundant epigenetic marks in mammalian genomes, and it has been proven that these dual epigenetic marks give a more accurate prediction of recurrence and survival in cancer than the individual mark. However, due to the similar structure and low expression of 5mC and 5hmC, it is challenging to distinguish and quantify the two methylation modifications. Herein, we employed the ten-eleven translocation family dioxygenases (TET) to convert 5mC to 5hmC via a specific labeling process, which realized the identification of the two marks based on a nanoconfined electrochemiluminescence (ECL) platform combined with the amplification strategy of a recombinase polymerase amplification (RPA)-assisted CRISPR/Cas13a system. Benefiting from the TET-mediated conversion strategy, a highly consistent labeling pathway was developed for identifying dual epigenetic marks on random sequence, which reduced the system error effectively. The ECL platform was established via preparing a carbonized polymer dot embedded SiO2 nanonetwork (CPDs@SiO2), which exhibited higher ECL efficiencies and more stable ECL performance compared to those of the scattered emitters due to the nanoconfinement-enhanced ECL effect. The proposed bioanalysis strategy could be employed for the identification and quantification of 5mC and 5hmC in the range from 100 aM to 100 pM, respectively, which provides a promising tool for early diagnosis of diseases associated with abnormal methylation.


Assuntos
5-Metilcitosina , Citosina , Animais , 5-Metilcitosina/metabolismo , Citosina/metabolismo , Sequência de Bases , Dióxido de Silício , Metilação de DNA , Mamíferos/metabolismo
5.
Forensic Sci Med Pathol ; 19(3): 464-467, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36169878

RESUMO

It is challenging in forensic pathology to determine whether an injury is formed antemortem or postmortem in putrefied tissues. Hematoxylin-eosin (HE) staining fails to work in highly decomposed corpses. Ponceau/Victoria blue B (P/VB) staining is usually used to show collagen fibers and muscles. Here, we used P/VB to show antemortem laceration injury on the scalp in a severely decomposed cadaver 1.5 years after death. This method is a simple and alternative method for the diagnosis of antemortem injury.


Assuntos
Lacerações , Mudanças Depois da Morte , Humanos , Cadáver , Patologia Legal , Coloração e Rotulagem
6.
Int J Legal Med ; 136(1): 85-91, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34125279

RESUMO

Aortic dissection (AD) usually remains undiagnosed, but its manifestation is abrupt and is associated with high morbidity and poor prognosis, leading to sudden cardiac death. Variants in COL family genes are associated with AD. In case 1, a 32-year-old Chinese man was admitted to the hospital with complaints of abdominal pain and died on the next day. In case 2, a 36-year-old Chinese woman was admitted to the hospital because of waist pain and died the next afternoon. According to autopsy findings, the cause of death in both cases was an acute cardiac tamponade, which was attributed to AD rupture. Whole-exome sequencing was performed on the blood collected from the hearts of the two deceased patients. Positive variants in COL family genes were found in both cases, without positive variants in other AD-associated genes. In case 1, a novel, likely pathogenic, missense variant was identified in COL6A1. In case 2, we identified one novel, likely pathogenic, frameshift deletion in COL23A1 and one novel, likely pathogenic, missense mutation in COL1A2. Based on these two cases, physicians should consider the role and significance of COL family gene mutations in AD in young patients. Furthermore, molecular anatomy is clearly necessary and significant in cases of sudden cardiac death attributed to AD, particularly in younger individuals.


Assuntos
Dissecção Aórtica , Adulto , Dissecção Aórtica/genética , Povo Asiático , Autopsia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/patologia , Feminino , Humanos , Masculino , Sequenciamento do Exoma
7.
Proc Natl Acad Sci U S A ; 116(32): 15774-15783, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31341082

RESUMO

CRISPR-Cas systems are now widely used for genome editing and transcriptional regulation in diverse organisms. The compact and portable nature of class 2 single effector nucleases, such as Cas9 or Cas12, has facilitated directed genome modifications in plants, animals, and microbes. However, most CRISPR-Cas systems belong to the more prevalent class 1 category, which hinges on multiprotein effector complexes. In the present study, we detail how the native type I-E CRISPR-Cas system, with a 5'-AAA-3' protospacer adjacent motif (PAM) and a 61-nucleotide guide CRISPR RNA (crRNA) can be repurposed for efficient chromosomal targeting and genome editing in Lactobacillus crispatus, an important commensal and beneficial microbe in the vaginal and intestinal tracts. Specifically, we generated diverse mutations encompassing a 643-base pair (bp) deletion (100% efficiency), a stop codon insertion (36%), and a single nucleotide substitution (19%) in the exopolysaccharide priming-glycosyl transferase (p-gtf). Additional genetic targets included a 308-bp deletion (20%) in the prophage DNA packaging Nu1 and a 730-bp insertion of the green fluorescent protein gene downstream of enolase (23%). This approach enables flexible alteration of the formerly genetically recalcitrant species L. crispatus, with potential for probiotic enhancement, biotherapeutic engineering, and mucosal vaccine delivery. These results also provide a framework for repurposing endogenous CRISPR-Cas systems for flexible genome targeting and editing, while expanding the toolbox to include one of the most abundant and diverse systems found in nature.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes , Lactobacillus crispatus/genética , Sequência de Bases , Loci Gênicos , Variação Genética , Lactobacillus crispatus/ultraestrutura , Motivos de Nucleotídeos/genética , RNA Guia de Cinetoplastídeos/genética
8.
Anal Chem ; 93(8): 4051-4058, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33587601

RESUMO

Here, we described a novel swing arm location-controllable DNA walker based on the DNA tetrahedral nanostructures (DTNs) for nucleic acid detection using the polycyclic aromatic hydrocarbon (PAH) microcrystals (TAPE-Pe MCs) consisting of the nonplanar molecular tetrakis(4-aminophenyl)ethene (TAPE) and planar molecular perylene (Pe) as electrochemiluminescence (ECL) luminophores. Specifically, the swing arm strands and track strands were fixed simultaneously on the DTNs to obtain the location-controllable DNA walker, which possessed an improved reaction efficiency compared to that of a fixed swing arm-based DNA walker due to the quantitative and orderly swing arm on the DTNs. On the other hand, the Pe microcrystals doped by TAPE molecules could decrease the π-π stacking of Pe molecules for the ECL efficiency enhancement, achieving a blue-shifted and intense ECL emission. Therefore, we defined this enhanced and blue-shifted ECL phenomenon as "inhibition of conjugation-driven ECL (IC-ECL)". To prove these principles, a location-controllable DNA walker-based ECL biosensor was developed with microRNA let-7a as target molecules. The ECL biosensor achieved a low detection limit of 4.92 fM within a wide linear range from 10 fM to 100 nM. This approach offers a new insight for ECL efficiency increase and location-controllable strategies with improved reaction efficiency, demonstrating potential in diagnostic analysis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Braço , DNA , Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes
9.
Biochem Biophys Res Commun ; 585: 177-184, 2021 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34808501

RESUMO

PURPOSE: Cervical squamous cell carcinoma (CESC) is the most common cancer type of cervical cancer, which threatens women's life seriously. LncRNA DGUOK-AS1has been reported to promote the biologic processes of CESC. We aim to figure out the role of DGUOK-AS1-miR-499a-5p-SPRR1B axis in modulating the CESC progression in vitro. METHODS: The levels of DGUOK-AS1, miR-499a-5p, and SPRR1B in CESC tissues and cells were examined by RT-qPCR. The interaction of DGUOK-AS1-miR-499a-5p-SPRR1B was verified by luciferase assay. Inhibition of DGUOK-AS1, miR-499a-5p, and SPRR1B was applied for exploring the biological function based on detection of cell viability, proliferation, migration, and apoptosis in CESC SiHa and HeLa cells. RESULTS: DGUOK-AS1 and SPRR1B expressions were obviously elevated, whereas the expression of miR-499a-5p was reduced in both CESC tissues and cells. Silencing of DGUOK-AS1 attenuated cell growth and boosted apoptosis of CESC cells. Notably, DGUOK-AS1 inhibited miR-499a-5p to release SPRR1B, which significantly accelerated the development of CESC. CONCLUSION: DGUOK-AS1sponging miR-499a-5p facilitated CESC cells progression by releasing SPRR1B in vitro. It provides a new sight for the treatment of CESC patients involving DGUOK-AS1-miR-499a-5p-SPRR1B.


Assuntos
Carcinoma de Células Escamosas/genética , Proteínas Ricas em Prolina do Estrato Córneo/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Apoptose/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Proteínas Ricas em Prolina do Estrato Córneo/metabolismo , Progressão da Doença , Feminino , Células HeLa , Humanos , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
10.
Neurochem Res ; 46(7): 1737-1746, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33830405

RESUMO

Glioma is the most frequent primary malignant brain tumor, which is characterized by high incidence and mortality, with a poor prognosis. Numerous studies have revealed the abnormal expression of long non-coding RNAs in gliomas. This study explored the effects and potential mechanism of LINC00663 in glioma. The LINC00663 levels and their prognostic values were analyzed from the GEO databases using bioinformatics. Also, LINC00663 expression in tissue samples and cell lines was measured using qRT-PCR. The roles of LINC00663 in glioma were confirmed using CCK8, EdU assay as well as Transwell tests. Moreover, the influences of LINC00663 on the AKT/mTOR signal cascades were detected using western blotting assay. LINC00663 expression was higher in both glioma tissues and cell lines than that in the normal brain tissues and human astrocytes. High expression of LINC00663 led to the low overall survival rate of patients with glioma. LINC00663 knockdown notably restrained cell proliferation, migration, and invasion abilities by decreasing the activation of AKT and mTOR. This study indicated that LINC00663 might have a cancer-promoting role in accelerating glioma development and progression through regulating AKT/mTOR pathway.


Assuntos
Glioma/metabolismo , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Glioma/diagnóstico , Humanos , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima/fisiologia
11.
Anal Chem ; 92(19): 13581-13587, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32893627

RESUMO

Copper nanoclusters (Cu NCs) as emerging luminescent metal NCs are gaining increasing attention owing to the comparatively low cost and high abundance of the Cu element in nature. However, it remains challenging to manipulate the optical properties of Cu NCs. Unlike most dispersed Cu NCs, whose luminescence efficiency was restricted by nonexcited relaxation, the Cu NCs confined in a porous poly-l-cysteine (poly-l-Cys) film were generated controllably with enhanced electrochemiluminescence (ECL) by in situ electrochemical reduction. Specifically, poly-l-Cys provided a porous structure to regulate the generation of Cu NCs within its holes, which not only increased the restriction on the intramolecular vibration and rotation of the ligands but also expedited the electron transfer near the electrode surface, reflecting in an enhancement of the ECL signal and efficiency. As an application of the confined Cu NCs, an ECL biosensor with high performance was constructed skillfully for highly sensitive detection of alkaline phosphatase (ALP), which adopted Cu NCs as the ECL luminophore and poly-l-Cys as a coreaction accelerator in a novel ECL ternary system (Cu NCs/S2O82-/poly-l-Cys). Furthermore, an ingenious target amplification based on the combination of a DNA walker and click chemistry was developed to convert ALP to DNA strands efficiently, achieving great improvement in the recognition efficiency. As a result, the biosensor had a low detection limit (9.5 × 10-7 U·L-1) and a wide linear range (10-8-10-2 U·L-1) for ALP detection, which showed great promise for the detection of non-nucleic acid targets and the diagnosis of diseases.


Assuntos
Fosfatase Alcalina/sangue , Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Nanopartículas Metálicas/química , Peptídeos/química , Fosfatase Alcalina/metabolismo , Cobre/química , Humanos , Tamanho da Partícula , Porosidade , Propriedades de Superfície
12.
Clin Genet ; 97(5): 704-711, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32154576

RESUMO

Aortic dissection (AD) is a heterogeneous genetic disease with high morbidity and mortality. Although many genes predispose patients to AD, the pathogenic spectrum remains incomplete. This study aims to (a) investigate whether genotype differences exist between Stanford A and B AD individuals, and (b) broaden the pathogenic genetic spectrum of AD and reported novel variants of AD-associated genes. The DNA of 72 unrelated Han Chinese individuals with AD was tested by whole-exome sequencing. Of 142 AD-associated genes, 10 pathogenic variants, and 48 likely pathogenic variants in 36 genes were identified among 39 cases. The diagnostic yield was 54.2%. Of the 58 positive variants, 27 were novel. FBN1 was the most frequently positive gene in both Stanford A and Stanford B. Twenty-seven positive variants from 18 COL family genes were distributed in 36.8% of Stanford A and 6.7% of Stanford B cases. We emphasize that positive variants of COL family genes show distribution predominance and strong pathogenicity in Stanford A, while positive variants of smooth muscle cell pathway genes present distribution advantages mainly in Stanford B cases. Our findings provide a new perspective for both the pathogenic mechanism and the treatment of AD.


Assuntos
Aneurisma da Aorta Torácica/genética , Sequenciamento do Exoma , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Adulto , Aneurisma da Aorta Torácica/patologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Mutação/genética
13.
Int J Legal Med ; 134(4): 1487-1493, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31802193

RESUMO

Custodial deaths refer to the death of an individual who is in prison, a detention center, or a police station. The present study aims to retrospectively analyze cases of custodial deaths examined at Tongji Medico Legal Expertise Center in Hubei (TMECH). A total of 172 out of 5853 cases were screened at TMECH from January 1999 to December 2016. Male preponderance was observed in 172 cases (male-female ratio: 5:1). Natural deaths accounted for the majority (70.93%), followed by suicide (16.28%), accidents (3.49%), homicides (4.65%), and undetermined causes (4.65%). The most common natural cause was cardiovascular disease. Custodial deaths occurred more frequently in prisons and detention houses than in police cells (63%, 63%, and 46%, respectively). Among the 172 cases, 105 deaths occurred after resuscitation failure despite the individual being sent to the hospital. The average age across cases was 36.3 years, and 90% of the deceased were aged under 50 years. Since there is no officially reported data regarding the prevalence of causes and manners of custodial deaths in China, our analysis contributes to enhancing the understanding of such deaths in central China and serves as a reference for law enforcement to develop a prevention program to reduce incidents of mortality in custody.


Assuntos
Causas de Morte/tendências , Estabelecimentos Correcionais , Mortalidade/tendências , Prisioneiros/estatística & dados numéricos , Adulto , China , Feminino , Humanos , Masculino , Estudos Retrospectivos
14.
Hemoglobin ; 40(2): 138-42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26865073

RESUMO

Thalassemia is one of the most prevalent inherited disease in southern China. However, there have been only a few epidemiological studies of thalassemia in the Chaoshan region of Guangdong Province, People's Republic of China (PRC). A total of 6231 unrelated subjects in two main geographical cities of the Chaoshan region was analyzed for thalassemia. Seven hundred and thirty-six cases of suspected thalassemia carriers with microcytosis [mean corpuscular volume (MCV) <82.0 fL] were found by complete blood cell (CBC) count, and were tested by reverse dot-blot gene chip to reveal a total of 331 mutant chromosomes, including 278 α-thalassemia (α-thal) alleles and 53 ß-thalassemia (ß-thal) alleles. The most common α-thal mutations were the Southeast Asian (- -(SEA)), followed by the -α(3.7) (rightward) and -α(4.2) (leftward) deletions. The two most common ß-thal mutations were HBB: c.316-197C>T and HBB: c.126_129delCTTT, accounting for 69.81% of the ß-thal defects in the studied individuals. In addition, a rare mutation, Cap +1 (A>C) (HBB: c.-50A>C) was described for the first time in the Chaoshan region. Our results gave a heterozygote frequency of 5.31% for common α- and ß-thal in the Chaoshan region, and also indicated a higher prevalence of thalassemia with a heterozygote frequency of 6.29% in Chaozhou, followed by Shantou (3.37%). This study provided a detailed prevalence and molecular characterization of thalassemia in the Chaoshan region, and will be valuable for developing a strategy for prevention of thalassemia and reducing excessive health care costs in this area.


Assuntos
Talassemia/epidemiologia , Talassemia/genética , Alelos , China/epidemiologia , Frequência do Gene , Genótipo , Geografia , Hemoglobinas Anormais/genética , Humanos , Mutação , Vigilância da População , Prevalência
15.
Med Sci Law ; 64(2): 121-125, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37337721

RESUMO

The school bus is an important mode of transportation for school-age children, and safety-related issues are always the focus of public concern. Fatal hyperthermia occurring in school buses is an uncommon type of school bus-related injury. An internet search using Chinese internet search engines based on various combinations of keywords including 'vehicles', 'school bus', 'children or babies', 'hyperthermia or heat stroke' and 'death' was performed. Forty-seven cases of fatal hyperthermia in children which occurred in school buses were retrieved in the study. High ambient temperature, younger age and poor management were identified as risk factors. There is a lack of consensus regarding the legal nature and liability for fatal hyperthermia occurring in school buses. Pre-employment education should be focused on awareness of the dangers of leaving children alone in a school bus. Most importantly, the relevant legislation and regulations on school buses should be implemented. An internal alarm-raising system is recommended to avoid this kind of tragedy.


Assuntos
Hipertermia Induzida , Veículos Automotores , Criança , Humanos , Meios de Transporte , China , Hipertermia
16.
Chem Sci ; 15(9): 3255-3261, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38425534

RESUMO

Here we report for the first time the phenomenon of continuously color-tunable electrochemiluminescence (ECL) from individual gold nanoclusters (Au NCs) confined in a porous hydrogel matrix by adjusting the concentration of the co-reactant. Specifically, the hydrogel-confined Au NCs exhibit strong dual-color ECL in an aqueous solution with triethylamine (TEA) as a co-reactant, with a record-breaking quantum yield of 95%. Unlike previously reported Au NCs, the ECL origin of the hydrogel-confined Au NCs is related to both the Au(0) kernel and the Au(i)-S surface. Surprisingly, the surface-related ECL of Au NCs exhibits a wide color-tunable range of 625-829 nm, but the core-related ECL remains constant at 489 nm. Theoretical and experimental studies demonstrate that the color-tunable ECL is caused by the dynamic surface reconstruction of Au NCs and TEA radicals. This work opens up new avenues for dynamically manipulating the ECL spectra of core-shell emitters in biosensing and imaging research.

17.
Mol Biol Rep ; 40(4): 3073-82, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23275194

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common inherited disorder worldwide including southern China. G6PD gene mutations cause deficiency of the enzyme and a large spectrum of diseases. High-resolution DNA melting (HRM) assay was recently introduced as a rapid, inexpensive and effective method for genotyping. But there was a shortcoming of this method that hemizygous and homozygous genotypes were not easily distinguished from wild-types. Here we used improved HRM method for a small-scale screening of G6PD-deficient variants among people of Meizhou region. Then all amplicons were ascertained by direct DNA sequencing. These results indicated that HRM method was a major technical advance for G6PD mutations screening.


Assuntos
Técnicas de Genotipagem/métodos , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , Desnaturação de Ácido Nucleico , Povo Asiático , China , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Humanos , Mutação , Análise de Sequência de DNA
18.
Foods ; 12(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37444193

RESUMO

Lactiplantibacillus pentosus, commonly isolated from commercial cucumber fermentation, is a promising candidate for starter culture formulation due to its ability to achieve complete sugar utilization to an end pH of 3.3. In this study, we conducted a comparative genomic analysis encompassing 24 L. pentosus and 3 Lactiplantibacillus plantarum isolates autochthonous to commercial cucumber fermentation and 47 lactobacillales reference genomes to determine species specificity and provide insights into niche adaptation. Results showed that metrics such as average nucleotide identity score, emulated Rep-PCR-(GTG)5, computed multi-locus sequence typing (MLST), and multiple open reading frame (ORF)-based phylogenetic trees can robustly and consistently distinguish the two closely related species. Phylogenetic trees based on the alignment of 587 common ORFs separated the L. pentosus autochthonous cucumber isolates from olive fermentation isolates into clade A and B, respectively. The L. pentosus autochthonous clade partitions into subclades A.I, A.II, and A.III, suggesting substantial intraspecies diversity in the cucumber fermentation habitat. The hypervariable sequences within CRISPR arrays revealed recent evolutionary history, which aligns with the L. pentosus subclades identified in the phylogenetic trees constructed. While L. plantarum autochthonous to cucumber fermentation only encode for Type II-A CRISPR arrays, autochthonous L. pentosus clade B codes for Type I-E and L. pentosus clade A hosts both types of arrays. L. pentosus 7.8.2, for which phylogeny could not be defined using the varied methods employed, was found to uniquely encode for four distinct Type I-E CRISPR arrays and a Type II-A array. Prophage sequences in varied isolates evidence the presence of adaptive immunity in the candidate starter cultures isolated from vegetable fermentation as observed in dairy counterparts. This study provides insight into the genomic features of industrial Lactiplantibacillus species, the level of species differentiation in a vegetable fermentation habitat, and diversity profile of relevance in the selection of functional starter cultures.

19.
Front Pharmacol ; 14: 1249041, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719847

RESUMO

Background: Dihydropteridone derivatives represent a novel class of PLK1 inhibitors, exhibiting promising anticancer activity and potential as chemotherapeutic drugs for glioblastoma. Objective: The aim of this study is to develop 2D and 3D-QSAR models to validate the anticancer activity of dihydropteridone derivatives and identify optimal structural characteristics for the design of new therapeutic agents. Methods: The Heuristic method (HM) was employed to construct a 2D-linear QSAR model, while the gene expression programming (GEP) algorithm was utilized to develop a 2D-nonlinear QSAR model. Additionally, the CoMSIA approach was introduced to investigate the impact of drug structure on activity. A total of 200 novel anti-glioma dihydropteridone compounds were designed, and their activity levels were predicted using chemical descriptors and molecular field maps. The compounds with the highest activity were subjected to molecular docking to confirm their binding affinity. Results: Within the analytical purview, the coefficient of determination (R2) for the HM linear model is elucidated at 0.6682, accompanied by an R2 cv of 0.5669 and a residual sum of squares (S2) of 0.0199. The GEP nonlinear model delineates coefficients of determination for the training and validation sets at 0.79 and 0.76, respectively. Empirical modeling outcomes underscore the preeminence of the 3D-QSAR model, succeeded by the GEP nonlinear model, whilst the HM linear model manifested suboptimal efficacy. The 3D paradigm evinced an exemplary fit, characterized by formidable Q2 (0.628) and R2 (0.928) values, complemented by an impressive F-value (12.194) and a minimized standard error of estimate (SEE) at 0.160. The most significant molecular descriptor in the 2D model, which included six descriptors, was identified as "Min exchange energy for a C-N bond" (MECN). By combining the MECN descriptor with the hydrophobic field, suggestions for the creation of novel medications were generated. This led to the identification of compound 21E.153, a novel dihydropteridone derivative, which exhibited outstanding antitumor properties and docking capabilities. Conclusion: The development of 2D and 3D-QSAR models, along with the innovative integration of contour maps and molecular descriptors, offer novel concepts and techniques for the design of glioblastoma chemotherapeutic agents.

20.
Hum Vaccin Immunother ; 19(2): 2261199, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37753771

RESUMO

A 20-month-old girl was diagnosed with Guillain - Barré syndrome (GBS) based on progressive muscle weakness, areflexia, and albuminocytologic dissociation of the cerebrospinal fluid. Despite timely and systematic treatment, she eventually became paralyzed. There is a temporal correlation between the girl's GBS and the DTaP vaccination, but the exact causal relationship between the two is still debatable. Furthermore, we summarized clinical features of other 45 published GBS cases after DTP vaccines (or vaccine substances containing tetanus) through a systematic review. The mean onset age, sex distribution, onset time after vaccination, detection of antiganglioside antibodies, and other basic clinical features of GBS after DTP vaccination (or vaccine substances containing tetanus) were analyzed. The temporal pattern of GBS after vaccination was similar to that of GBS after infection. Herein, we report this rare case of presumptive pediatric GBS after DTaP vaccination and review similar cases to draw the attention of medical personnel to similar events after vaccination. An association between DTP vaccines and GBS has been proposed, and the causal relationship between these two incidents are worthy further exploration. Moreover, surveillance and vigilance for GBS after vaccination are highly recommended.


Assuntos
Vacina contra Difteria, Tétano e Coqueluche , Síndrome de Guillain-Barré , Feminino , Humanos , Lactente , Vacina contra Difteria, Tétano e Coqueluche/efeitos adversos , Síndrome de Guillain-Barré/induzido quimicamente
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