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1.
Oncol Lett ; 28(2): 348, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38872856

RESUMO

Skin metastasis from ovarian cancer is rare, and its prognosis is poor. Effective therapeutic strategies are currently lacking, but the combination of various treatment methods shrink the tumor and relieve symptoms. The present study reports a rare case of advanced ovarian cancer with skin metastases and intestinal wall thickening, along with a BRCA1 DNA repair associated (BRCA1) mutation. After standard first-line treatment and non-standard second-line treatment, the patient developed skin metastases. The patient's skin itching, pain and lesions were completely relieved after administering bevacizumab in combination with paclitaxel and carboplatin. After 4 months, skin metastases recurred along with anal distension during maintenance treatment with oral poly(ADP ribose) polymerase (PARP) inhibitors. The patient was treated again with bevacizumab combined with docetaxel, and the anal distension was significantly relieved. Angiogenesis therapy combined with chemotherapy is effective, but that the disease-free survival time is short, and PARP inhibitor maintenance effect is limited even in cases with a BRCA1 gene mutation.

2.
Nat Food ; 5(5): 413-422, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38724686

RESUMO

Salmonella enterica causes severe food-borne infections through contamination of the food supply chain. Its evolution has been associated with human activities, especially animal husbandry. Advances in intensive farming and global transportation have substantially reshaped the pig industry, but their impact on the evolution of associated zoonotic pathogens such as S. enterica remains unresolved. Here we investigated the population fluctuation, accumulation of antimicrobial resistance genes and international serovar Choleraesuis transmission of nine pig-enriched S. enterica populations comprising more than 9,000 genomes. Most changes were found to be attributable to the developments of the modern pig industry. All pig-enriched salmonellae experienced host transfers in pigs and/or population expansions over the past century, with pigs and pork having become the main sources of S. enterica transmissions to other hosts. Overall, our analysis revealed strong associations between the transmission of pig-enriched salmonellae and the global pork trade.


Assuntos
Salmonella enterica , Animais , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Suínos , Europa (Continente)/epidemiologia , Humanos , Salmonelose Animal/epidemiologia , Salmonelose Animal/transmissão , Salmonelose Animal/microbiologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/epidemiologia , Criação de Animais Domésticos/métodos , Carne de Porco/microbiologia , América/epidemiologia , Microbiologia de Alimentos
3.
BMC Cancer ; 24(1): 478, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622651

RESUMO

BACKGROUND: Pancreatic cancer is the foremost contributor to cancer-related deaths globally, and its prevalence continues to rise annually. Nevertheless, the underlying mechanisms behind its development remain unclear and necessitate comprehensive investigation. METHODS: In this study, a total of 29 fresh stool samples were collected from patients diagnosed with pancreatic cancer. The gut microbial data of healthy controls were obtained from the SRA database (SRA data number: SRP150089). Additionally, 28 serum samples and diseased tissues were collected from 14 patients with confirmed pancreatic cancer and 14 patients with chronic pancreatitis. Informed consent was obtained from both groups of patients. Microbial sequencing was performed using 16s rRNA. RESULTS: The results showed that compared with healthy controls, the species abundance index of intestinal flora in patients with pancreatic cancer was increased (P < 0.05), and the number of beneficial bacteria at the genus level was reduced (P < 0.05). Compared with patients with chronic pancreatitis, the expression levels of CA242 and CA199 in the serum of patients with pancreatic cancer were increased (P < 0.05). The bacterial richness index of tumor microorganisms in patients with pancreatic cancer increased, while the diversity index decreased(P < 0.05). Furthermore, there was a change in the species composition at the genus level. Additionally, the expression level of CA242 was found to be significantly positively correlated with the relative abundance of Acinetobacter(P < 0.05). CONCLUSION: Over all, the expression levels of serum tumor markers CA242 and CA19-9 in patients with pancreatic cancer are increased, while the beneficial bacteria in the intestine and tumor microenvironment are reduced and pathogenic bacteria are increased. Acinetobacter is a specific bacterial genus highly expressed in pancreatic cancer tissue.


Assuntos
Microbiota , Neoplasias Pancreáticas , Pancreatite Crônica , Humanos , Antígenos Glicosídicos Associados a Tumores , RNA Ribossômico 16S/genética , Neoplasias Pancreáticas/diagnóstico , Bactérias/genética , Pancreatite Crônica/genética , Microambiente Tumoral
4.
BMC Microbiol ; 24(1): 94, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519882

RESUMO

BACKGROUND: Cervicovaginal microbiome plays an important role in the persistence of HPV infection and subsequent disease development. However, cervicovaginal microbiota varied cross populations with different habits and regions. Identification of population-specific biomarkers from cervicovaginal microbiota and host metabolome axis may support early detection or surveillance of HPV-induced cervical disease at all sites. Therefore, in the present study, to identify HPV-specific biomarkers, cervicovaginal secretion and serum samples from HPV-infected patients (HPV group, n = 25) and normal controls (normal group, n = 17) in Xichang, China were collected for microbiome (16S rRNA gene sequencing) and metabolome (UHPLC-MS/MS) analysis, respectively. RESULTS: The results showed that key altered metabolites of 9,10-DiHOME, α-linolenic acid, ethylparaben, glycocholic acid, pipecolic acid, and 9,12,13-trihydroxy-10(E),15(Z)-octadecadienoic acid, correlating with Sneathia (Sneathia_amnii), Lactobacillus (Lactobacillus_iners), Atopobium, Mycoplasma, and Gardnerella, may be potential biomarkers of HPV infection. CONCLUSION: The results of current study would help to reveal the association of changes in cervicovaginal microbiota and serum metabolome with HPV infections.


Assuntos
Microbiota , Infecções por Papillomavirus , Feminino , Humanos , Vagina , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem , Metaboloma , Microbiota/genética , Biomarcadores/metabolismo
5.
Angew Chem Int Ed Engl ; 63(14): e202318897, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38326236

RESUMO

Mirror-image proteins (D-proteins) are useful in biomedical research for purposes such as mirror-image screening for D-peptide drug discovery, but the chemical synthesis of many D-proteins is often low yielding due to the poor solubility or aggregation of their constituent peptide segments. Here, we report a Lys-C protease-cleavable solubilizing tag and its use to synthesize difficult-to-obtain D-proteins. Our tag is easily installed onto multiple amino acids such as DLys, DSer, DThr, and/or the N-terminal amino acid of hydrophobic D-peptides, is impervious to various reaction conditions, such as peptide synthesis, ligation, desulfurization, and transition metal-mediated deprotection, and yet can be completely removed by Lys-C protease under denaturing conditions to give the desired D-protein. The efficacy and practicality of the new method were exemplified in the synthesis of two challenging D-proteins: D-enantiomers of programmed cell death protein 1 IgV domain and SARS-CoV-2 envelope protein, in high yield. This work demonstrates that the enzymatic cleavage of solubilizing tags under denaturing conditions is feasible, thus paving the way for the production of more D-proteins.


Assuntos
Peptídeos , Proteínas , Proteínas/química , Peptídeos/química , Aminoácidos/química , Técnicas de Química Sintética/métodos , Peptídeo Hidrolases , Endopeptidases
6.
Front Immunol ; 15: 1357601, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348039

RESUMO

Background: Despite the significant progress made in radiotherapy and chemotherapy for the treatment of cervical cancer, patients with lymph node metastasis still have a poor prognosis. It is widely accepted that lymph node metastasis plays a crucial role in the spread of cancer to other organs and is considered an independent factor in predicting a poor prognosis. However, recent research suggests that the importance of lymph nodes in tumor therapy needs to be reevaluated, as preserving the integrity of lymph nodes before immunotherapy can enhance treatment effectiveness. Case presentation: In this report, we present two cases of advanced cervical cancer patients with giant metastatic lymph node lesions in the neck. These patients were effectively treated with a combination of local radiotherapy and immunotherapy after conventional chemoradiotherapy had failed. The combination therapy resulted in significant clinical improvements, with patient 1 achieving over 12 months of progression-free survival (PFS) and patient 2 maintaining sustained remission for an impressive 24 months. Conclusions: The combination of local radiotherapy and immunotherapy shows promise as a viable treatment option for cervical cancer patients with distant lymph node metastasis, and the giant lymph node metastases may play an important role in this process, which might provide a new opportunity for cancer radioimmunotherapy.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Metástase Linfática/radioterapia , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/patologia , Radioimunoterapia , Quimiorradioterapia , Terapia Combinada
7.
Angew Chem Int Ed Engl ; 63(9): e202313640, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38193587

RESUMO

D-peptide ligands can be screened for therapeutic potency and enzymatic stability using synthetic mirror-image proteins (D-proteins), but efficient acquisition of these D-proteins can be hampered by the need to accomplish their in vitro folding, which often requires the formation of correctly linked disulfide bonds. Here, we report the finding that temporary installation of natural O-linked-ß-N-acetyl-D-glucosamine (O-GlcNAc) groups onto selected D-serine or D-threonine residues of the synthetic disulfide-bonded D-proteins can facilitate their folding in vitro, and that the natural glycosyl groups can be completely removed from the folded D-proteins to afford the desired chirally inverted D-protein targets using naturally occurring O-GlcNAcase. This approach enabled the efficient chemical syntheses of several important but difficult-to-fold D-proteins incorporating disulfide bonds including the mirror-image tumor necrosis factor alpha (D-TNFα) homotrimer and the mirror-image receptor-binding domain of the Omicron spike protein (D-RBD). Our work establishes the use of O-GlcNAc to facilitate D-protein synthesis and folding and proves that D-proteins bearing O-GlcNAc can be good substrates for naturally occurring O-GlcNAcase.


Assuntos
Acetilglucosaminidase , Proteínas , Peptídeos , Polissacarídeos , Glucosamina
8.
Nat Commun ; 14(1): 7706, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001084

RESUMO

Core genome multilocus sequence typing (cgMLST) is commonly used to classify bacterial strains into different types, for taxonomical and epidemiological applications. However, cgMLST schemes require central databases for the nomenclature of new alleles and sequence types, which must be synchronized worldwide and involve increasingly intensive calculation and storage demands. Here, we describe a distributed cgMLST (dcgMLST) scheme that does not require a central database of allelic sequences and apply it to study evolutionary patterns of epidemic and endemic strains of the genus Neisseria. We classify 69,994 worldwide Neisseria strains into multi-level clusters that assign species, lineages, and local disease outbreaks. We divide Neisseria meningitidis into 168 endemic lineages and three epidemic lineages responsible for at least 9 epidemics in the past century. According to our analyses, the epidemic and endemic lineages experienced very different population dynamics in the past 100 years. Epidemic lineages repetitively emerged from endemic lineages, disseminated worldwide, and apparently disappeared rapidly afterward. We propose a stepwise model for the evolutionary trajectory of epidemic lineages in Neisseria, and expect that the development of similar dcgMLST schemes will facilitate epidemiological studies of other bacterial pathogens.


Assuntos
Neisseria meningitidis , Neisseria meningitidis/genética , Neisseria/genética , Genoma Bacteriano/genética , Genótipo , Tipagem de Sequências Multilocus , Análise por Conglomerados
9.
Nat Commun ; 14(1): 5845, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730702

RESUMO

The CRISPR-Cas13 ribonucleases have been widely applied for RNA knockdown and transcriptional modulation owing to their high programmability and specificity. However, the large size of Cas13 effectors and their non-specific RNA cleavage upon target activation limit the adeno-associated virus based delivery of Cas13 systems for therapeutic applications. Herein, we report detailed biochemical and structural characterizations of a compact Cas13 (Cas13bt3) suitable for adeno-associated virus delivery. Distinct from many other Cas13 systems, Cas13bt3 cleaves the target and other nonspecific RNA at internal "UC" sites and is activated in a target length-dependent manner. The cryo-electron microscope structure of Cas13bt3 in a fully active state illustrates the structural basis of Cas13bt3 activation. Guided by the structure, we obtain engineered Cas13bt3 variants with minimal off-target cleavage yet maintained target cleavage activities. In conclusion, our biochemical and structural data illustrate a distinct mechanism for Cas13bt3 activation and guide the engineering of Cas13bt3 applications.


Assuntos
Sistemas CRISPR-Cas , Dependovirus , Microscopia Crioeletrônica , Dependovirus/genética , Endonucleases/genética , RNA
10.
ISME Commun ; 3(1): 85, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598265

RESUMO

Comprehending bacterial genomic variation linked to distinct environments can yield novel insights into mechanisms underlying differential adaptation and transmission of microbes across environments. Gaining such insights is particularly crucial for pathogens as it benefits public health surveillance. However, the understanding of bacterial genomic variation is limited by a scarcity of investigations in genomic variation coupled with different ecological contexts. To address this limitation, we focused on Listeria, an important bacterial genus for food safety that includes the human pathogen L. monocytogenes, and analyzed a large-scale genomic dataset collected by us from natural and food-associated environments across the United States. Through comparative genomics analyses on 449 isolates from the soil and 390 isolates from agricultural water and produce processing facilities representing L. monocytogenes, L. seeligeri, L. innocua, and L. welshimeri, we find that the genomic profiles strongly differ by environments within each species. This is supported by the environment-associated subclades and differential presence of plasmids, stress islands, and accessory genes involved in cell envelope biogenesis and carbohydrate transport and metabolism. Core genomes of Listeria species are also strongly associated with environments and can accurately predict isolation sources at the lineage level in L. monocytogenes using machine learning. We find that the large environment-associated genomic variation in Listeria appears to be jointly driven by soil property, climate, land use, and accompanying bacterial species, chiefly representing Actinobacteria and Proteobacteria. Collectively, our data suggest that populations of Listeria species have genetically adapted to different environments, which may limit their transmission from natural to food-associated environments.

11.
J Glob Antimicrob Resist ; 34: 176-178, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37429544

RESUMO

OBJECTIVES: We isolated a highly colistin-resistant Escherichia coli, strain 58, from fresh chicken wings in Lebanon. Here, we performed in-depth phenotypic and genomic analyses to identify the resistome of the isolate, focusing on the determinants that encoded colistin resistance. METHODS: The minimum inhibitory concentration (MIC) of colistin and resistance to other antibiotics were determined using the broth microdilution method and the Kirby-Bauer disk diffusion assay, respectively. Whole-genome sequencing (WGS) and different software available at the Center of Genomic Epidemiology were used to predict the resistome, the sequence type (ST), and the presence of virulence genes and plasmid replicon types. RESULTS: Susceptibility testing revealed that E. coli 58 exhibited multidrug resistance, including against colistin (MIC = 32 µg/mL). Whole-genome sequencing analyses showed that E. coli 58 carried 26 antimicrobial resistance genes associated with resistance to polymyxins (mcr-1.26), ß-lactams (blaTEM-1b and blaCMY-2), fosfomycin (fosA4), aminoglycosides (aac(3)-IId, aadA2b, aadA5, partial aadA1, aph(3'')-Ia, aph(3')-Ia, and aph(6)-Id), tetracyclines (tetA and tetM), quinolones (qnrS1), sulphonamides (sul2 and sul3), trimethoprim (dfrA14, dfrA17, and dfrA5), phenicols (floR and cmlA1), macrolides (mphA), lincosamides (lnu(F)), quaternary ammonium compounds (partial qacL and qacE), and peroxides (sitABCD). mcr-1.26 was located on an IncX4 plasmid and induced colistin resistance in otherwise naïve E. coli and Salmonella Enteritidis. Escherichia coli 58 was predicted to be a human pathogen and belonged to ST3107. CONCLUSION: To our knowledge, this is the first report of mcr-1.26 in poultry meat worldwide. We previously reported mcr-1.26 in an MDR E. coli (ST2207) isolated from a pigeon in Lebanon, which suggests that it might be spreading in different animal hosts and genetic backgrounds.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Animais , Humanos , Colistina/farmacologia , Galinhas , Proteínas de Escherichia coli/genética , Antibacterianos/farmacologia , Carne
12.
Angew Chem Int Ed Engl ; 62(33): e202306270, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37357888

RESUMO

Membrane-associated D-proteins are an important class of synthetic molecules needed for D-peptide drug discovery, but their chemical synthesis using canonical ligation methods such as native chemical ligation is often hampered by the poor solubility of their constituent peptide segments. Here, we describe a Backbone-Installed Split Intein-Assisted Ligation (BISIAL) method for the synthesis of these proteins, wherein the native L-forms of the N- and C-intein fragments of the unique consensus-fast (Cfa) (i.e. L-CfaN and L-CfaC ) are separately installed onto the two D-peptide segments to be ligated via a removable backbone modification. The ligation proceeds smoothly at micromolar (µM) concentrations under strongly chaotropic conditions (8.0 M urea), and the subsequent removal of the backbone modification groups affords the desired D-proteins without leaving any "ligation scar" on the products. The effectiveness and practicality of the BISIAL method are exemplified by the synthesis of the D-enantiomers of the extracellular domains of T cell immunoglobulin and ITIM domain (TIGIT) and tropomyosin receptor kinase C (TrkC). The BISIAL method further expands the chemical protein synthesis ligation toolkit and provides practical access to challenging D-protein targets.


Assuntos
Inteínas , Proteínas , Peptídeos/química , Processamento de Proteína
13.
Talanta ; 260: 124604, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141825

RESUMO

Herein, a ternary PdPtRu nanodendrite as novel trimetallic nanozyme was reported, which possessed excellent peroxidase-like activity as well as electro-catalytic activity on account of the synergistic effect between the three metals. Based on the excellent electro-catalytic activity of trimetallic PdPtRu nanozyme toward the reduction of H2O2, the trimetallic nanozyme was applied to construct a brief electrochemical immunosensor for SARS-COV-2 antigen detection. Concretely, trimetallic PdPtRu nanodendrite was used to modify electrode surface, which not only generated high reduction current of H2O2 for signal amplification, but also provided massive active sites for capture antibody (Ab1) immobilization to construct immunosensor. In the presence of target SARS-COV-2 antigen, SiO2 nanosphere labeled detection antibody (Ab2) composites were introduced on the electrode surface according sandwich immuno-reaction. Due to the inhibitory effect of SiO2 nanosphere on the current signal, the current signal was decreased with the increasing target SARS-COV-2 antigen concentration. As a result, the proposed electrochemical immunosensor presented sensitive detection of SARS-COV-2 antigen with linear range from 1.0 pg/mL to 1.0 µg/mL and limit of detection down to 51.74 fg/mL. The proposed immunosensor provide a brief but sensitive antigen detection tool for rapid diagnosis of COVID-19.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/química , SARS-CoV-2 , Imunoensaio , Peróxido de Hidrogênio/química , Dióxido de Silício , COVID-19/diagnóstico , Anticorpos , Anticorpos Imobilizados/química , Ouro/química , Técnicas Eletroquímicas , Limite de Detecção
14.
J Food Prot ; 86(5): 100013, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018852

RESUMO

Comparisons among a qPCR assay, VIDAS® assays and a conventional agar streaking method following the same enrichment for the detection of Listeria monocytogenes were performed under two challenging conditions. In the first comparison, L. innocua and L. monocytogenes were coinoculated into sausages at ratios (L. innocua-to-L. monocytogenes) of 10, 100, 1000, and 10 000. qPCR provided the most sensitive detection at all ratios after both 24-h and 48-h enrichments. A modified VIDAS® LMO2 assay (i.e., replacement of the kit-specified enrichment scheme with the enrichment scheme used in this study) and agar streaking yielded equivalent results when the ratio was 10 and 100; agar streaking was more sensitive when the ratio was 1000; neither method could detect L. monocytogenes at the ratio of 10 000. Enrichment duration of 48 h was needed for modified VIDAS® to detect L. monocytogenes when the ratio was 1000. Agar streaking after 24-h enrichment isolated L. monocytogenes better than after 48-h enrichment when the ratio was 100 and 1000. In the second comparison, we followed the validation guidelines of AOAC International and inoculated L. monocytogenes, without any L. innocua, onto lettuce and stainless-steel surfaces at low levels. The numbers of positive samples detected by qPCR, VIDAS® LIS assay, modified VIDAS® LMO2 assay, and agar streaking after 48-h enrichment were not statistically different. Our data showed that qPCR was the most sensitive method, while agar streaking and VIDAS® performed reasonably well. Streaking after 24-h enrichment was needed when background flora could overgrow L. monocytogenes during prolonged enrichment, and this is critical for confirming rapid screening assays. Appropriate selection of enrichment duration and rapid assays will enhance the testing of L. monocytogenes in food and environmental samples.


Assuntos
Listeria monocytogenes , Listeria , Produtos da Carne , Ágar , Microbiologia de Alimentos , Imunoensaio
15.
J Orthop Surg Res ; 18(1): 40, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36642708

RESUMO

BACKGROUND: Accumulated evidence indicates that cholesterol is offensive to bone metabolism. Therefore, we examined the real-world study among total cholesterol and total bone mineral density (BMD). We investigated the relationship between total cholesterol and total BMD among 10,039 US participants aged 20-59 years old over the period 2011-2018 from the NHANES. METHODS: To analyze the relationship among total cholesterol and total BMD, multivariate linear regression models were used. Fitted smoothing curves, generalized additive models, and threshold effect analysis were also conducted. RESULTS: After adjusting for additional covariates, weighted multivariable linear regression models indicated total cholesterol concentration levels exhibited a negative relationship with total BMD, particularly among participants aged 20-29 years. Concerning subgroup analysis, stratified by gender, race/ethnicity and age group, the negative correlation of total cholesterol with total BMD dwelled in both female and male as well as in whites and other races (including Hispanic and Multi-Racial), but not in non-Hispanic blacks and Mexican American. In other races, this relationship presented a nonlinear association (inflection point: 6.7 mmol/L) with a U-shaped curve. Among participants aged 40 to 49 years, this relationship also followed a nonlinear association (inflection point: 5.84 mmol/L), indicating a saturation effect. Moreover, the three types of diabetes status were found to have negative, U-shaped, and positive relationships. In participants with borderline diabetes status, the relationship of total cholesterol with total BMD was a U-shaped curve (inflection point: 4.65 mmol/L). CONCLUSIONS: For US young adults (20-29 years old), our study revealed a negative relationship between total cholesterol and total BMD. This association followed a U-shaped curve (inflection point: 4.65 mmol/L) in borderline diabetes status participants, a saturation curve (inflection point: 5.84 mmol/L) in participants aged 40-49 years and a nonlinear curve (inflection point: 6.7 mmol/L) in other races (including Hispanic and Multi-Racial). Therefore, keeping total cholesterol concentration at a reasonable level for young adults and diabetic population might be an approach to prevent osteoporosis or osteopenia.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Absorciometria de Fóton , Densidade Óssea , Inquéritos Nutricionais , Grupos Populacionais , Estados Unidos
16.
Nat Chem Biol ; 19(1): 45-54, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36138140

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 13 (Cas13) has been rapidly developed for nucleic-acid-based diagnostics by using its characteristic collateral activity. Despite the recent progress in optimizing the Cas13 system for the detection of nucleic acids, engineering Cas13 protein with enhanced collateral activity has been challenging, mostly because of its complex structural dynamics. Here we successfully employed a novel strategy to engineer the Leptotrichia wadei (Lwa)Cas13a by inserting different RNA-binding domains into a unique active-site-proximal loop within its higher eukaryotes and prokaryotes nucleotide-binding domain. Two LwaCas13a variants showed enhanced collateral activity and improved sensitivity over the wild type in various buffer conditions. By combining with an electrochemical method, our variants detected the SARS-CoV-2 genome at attomolar concentrations from both inactive viral and unextracted clinical samples, without target preamplification. Our engineered LwaCas13a enzymes with enhanced collateral activity are ready to be integrated into other Cas13a-based platforms for ultrasensitive detection of nucleic acids.


Assuntos
COVID-19 , Ácidos Nucleicos , Humanos , SARS-CoV-2/genética , Ácidos Nucleicos/genética , Genoma , Sistemas CRISPR-Cas/genética
17.
Front Oncol ; 13: 1330681, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288097

RESUMO

Background: Treatment of metastatic cervical cancer is a tricky issue. Currently, the National Comprehensive Cancer Network (NCCN) guideline recommends chemotherapy combined with bevacizumab for recurrent or metastatic cervical cancer. Still, the recurrence rate is high and the survival rate is low after standard treatment. We urgently need to achieve a multimodal therapy approach for recurrent or metastatic cervical cancer. Case description: We report the case of a patient with stage IB2 cervical squamous carcinoma who developed multiple metastases within a short term after receiving first-line standard treatment, and she underwent interstitial brachytherapy after systemic therapy with an encouraging outcome. The patient developed suspected inguinal lymph node metastases after 9 months at the end of first-line therapy and multiple metastases in the inguinal lymph nodes, anterior abdominal wall, and right lung after 17 months. As the patient had residual inguinal lymph nodes after systemic therapy, she received 3D-printed template-guided interstitial brachytherapy to the inguinal lymph nodes and maintenance therapy. By Sep 2023, she had achieved a good treatment outcome with a progression-free survival (PFS) of 36 months. Conclusion: Based on our patient response, when multiple metastases develop in the short term in early-stage cervical squamous carcinoma after first-line therapy, we may consider implementing local therapy combined with systemic therapy.

18.
Front Microbiol ; 14: 1295769, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38164401

RESUMO

Salmonella, especially antimicrobial resistant strains, remains one of the leading causes of foodborne bacterial disease. Retail chicken is a major source of human salmonellosis. Here, we investigated the prevalence, antimicrobial resistance (AMR), and genomic characteristics of Salmonella in 88 out of 360 (24.4%) chilled chicken carcasses, together with 86 Salmonella from humans with diarrhea in Qingdao, China in 2020. The most common serotypes were Enteritidis and Typhimurium (including the serotype I 4,[5],12:i:-) among Salmonella from both chicken and humans. The sequence types were consistent with serotypes, with ST11, ST34 and ST19 the most dominantly identified. Resistance to nalidixic acid, ampicillin, tetracycline and chloramphenicol were the top four detected in Salmonella from both chicken and human sources. High multi-drug resistance (MDR) and resistance to third-generation cephalosporins resistance were found in Salmonella from chicken (53.4%) and humans (75.6%). In total, 149 of 174 (85.6%) Salmonella isolates could be categorized into 60 known SNP clusters, with 8 SNP clusters detected in both sources. Furthermore, high prevalence of plasmid replicons and prophages were observed among the studied isolates. A total of 79 antimicrobial resistant genes (ARGs) were found, with aac(6')-Iaa, blaTEM-1B, tet(A), aph(6)-Id, aph(3″)-Ib, sul2, floR and qnrS1 being the dominant ARGs. Moreover, nine CTX-M-type ESBL genes and the genes blaNMD-1, mcr-1.1, and mcr-9.1 were detected. The high incidence of MDR Salmonella, especially possessing lots of mobile genetic elements (MGEs) in this study posed a severe risk to food safety and public health, highlighting the importance of improving food hygiene measures to reduce the contamination and transmission of this bacterium. Overall, it is essential to continue monitoring the Salmonella serotypes, implement the necessary prevention and strategic control plans, and conduct an epidemiological surveillance system based on whole-genome sequencing.

19.
Front Immunol ; 14: 1329951, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38235148

RESUMO

Background: Treatment for platinum-resistant ovarian cancer is challenging. Currently, platinum-resistant ovarian cancer is typically treated with non-platinum single-agent chemotherapy ± bevacizumab, but the prognosis is often extremely poor. In the treatment of platinum-resistant ovarian cancer patients, reports of triple therapy with interstitial implantation radiotherapy combined with immunotherapy and granulocyte-macrophage colony-stimulating factor (GM-CSF) (PRaG for short) are relatively rare. Case description: Here, we report a patient with oligometastatic platinum-resistant ovarian cancer. The patient achieved partial response (PR) of the lesion and sustained benefit for more than six months after receiving interstitial implantation radiotherapy combined with immunotherapy along with GM-CSF. Conclusion: This triple therapy may provide additional options for these patients.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos , Neoplasias Ovarianas , Humanos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Bevacizumab/uso terapêutico , Prognóstico , Imunoterapia , Neoplasias Ovarianas/terapia , Neoplasias Ovarianas/patologia
20.
Microbiol Resour Announc ; 11(12): e0096522, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36383023

RESUMO

Sewage has been established as a prime matrix for monitoring the emergence and dissemination of etiologic agents and antibiotic resistance determinants in a population. Here, we report the draft genomes and the acquired resistance genes of 11 antibiotic-resistant Serratia sp. isolates that were detected in samples from wastewater treatment plants.

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