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1.
Cell ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39094567

RESUMO

Our understanding of the normal variation in the upper respiratory tract (URT) microbiota across the human lifespan and how these relate to host, environment, and health is limited. We studied the microbiota of 3,104 saliva (<10 year-olds)/oropharynx (≥10 year-olds) and 2,485 nasopharynx samples of 3,160 Dutch individuals 0-87 years of age, participating in a cross-sectional population-wide study (PIENTER-3) using 16S-rRNA sequencing. The microbiota composition was strongly related to age, especially in the nasopharynx, with maturation occurring throughout childhood and adolescence. Clear niche- and age-specific associations were found between the microbiota composition and host/environmental factors and health outcomes. Among others, social interaction, sex, and season were associated with the nasopharyngeal microbial community. By contrast, the oral microbiota was more related to antibiotics, tobacco, and alcohol use. We present an atlas of the URT microbiota across the lifespan in association with environment and health, establishing a baseline for future research.

2.
Mol Cell ; 83(22): 4123-4140.e12, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37848033

RESUMO

Purinosomes serve as metabolons to enhance de novo purine synthesis (DNPS) efficiency through compartmentalizing DNPS enzymes during stressed conditions. However, the mechanism underpinning purinosome assembly and its pathophysiological functions remains elusive. Here, we show that K6-polyubiquitination of the DNPS enzyme phosphoribosylaminoimidazole carboxylase and phosphoribosylaminoimidazolesuccinocarboxamide synthetase (PAICS) by cullin-5/ankyrin repeat and SOCS box containing 11 (Cul5/ASB11)-based ubiquitin ligase plays a driving role in purinosome assembly. Upon several purinosome-inducing cues, ASB11 is upregulated by relieving the H3K9me3/HP1α-mediated transcriptional silencing, thus stimulating PAICS polyubiquitination. The polyubiquitinated PAICS recruits ubiquitin-associated protein 2 (UBAP2), a ubiquitin-binding protein with multiple stretches of intrinsically disordered regions, thereby inducing phase separation to trigger purinosome assembly for enhancing DNPS pathway flux. In human melanoma, ASB11 is highly expressed to facilitate a constitutive purinosome formation to which melanoma cells are addicted for supporting their proliferation, viability, and tumorigenesis in a xenograft model. Our study identifies a driving mechanism for purinosome assembly in response to cellular stresses and uncovers the impact of purinosome formation on human malignancies.


Assuntos
Ligases , Melanoma , Humanos , Células HeLa , Ubiquitinação , Ubiquitinas
3.
Nature ; 605(7911): 761-766, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35585240

RESUMO

Diabetes mellitus is prevalent among women of reproductive age, and many women are left undiagnosed or untreated1. Gestational diabetes has profound and enduring effects on the long-term health of the offspring2,3. However, the link between pregestational diabetes and disease risk into adulthood in the next generation has not been sufficiently investigated. Here we show that pregestational hyperglycaemia renders the offspring more vulnerable to glucose intolerance. The expression of TET3 dioxygenase, responsible for 5-methylcytosine oxidation and DNA demethylation in the zygote4, is reduced in oocytes from a mouse model of hyperglycaemia (HG mice) and humans with diabetes. Insufficient demethylation by oocyte TET3 contributes to hypermethylation at the paternal alleles of several insulin secretion genes, including the glucokinase gene (Gck), that persists from zygote to adult, promoting impaired glucose homeostasis largely owing to the defect in glucose-stimulated insulin secretion. Consistent with these findings, mouse progenies derived from the oocytes of maternal heterozygous and homozygous Tet3 deletion display glucose intolerance and epigenetic abnormalities similar to those from the oocytes of HG mice. Moreover, the expression of exogenous Tet3 mRNA in oocytes from HG mice ameliorates the maternal effect in offspring. Thus, our observations suggest an environment-sensitive window in oocyte development that confers predisposition to glucose intolerance in the next generation through TET3 insufficiency rather than through a direct perturbation of the oocyte epigenome. This finding suggests a potential benefit of pre-conception interventions in mothers to protect the health of offspring.


Assuntos
Dioxigenases , Intolerância à Glucose , Hiperglicemia , Oócitos , Adulto , Animais , Dioxigenases/metabolismo , Feminino , Glucose/metabolismo , Intolerância à Glucose/genética , Intolerância à Glucose/metabolismo , Humanos , Hiperglicemia/complicações , Hiperglicemia/genética , Hiperglicemia/metabolismo , Herança Materna , Camundongos , Oócitos/metabolismo
4.
Proc Natl Acad Sci U S A ; 121(25): e2316615121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38861602

RESUMO

Many cancer-driving protein targets remain undruggable due to a lack of binding molecular scaffolds. In this regard, octahedral metal complexes with unique and versatile three-dimensional structures have rarely been explored as inhibitors of undruggable protein targets. Here, we describe antitumor iridium(III) pyridinium-N-heterocyclic carbene complex 1a, which profoundly reduces the viability of lung and breast cancer cells as well as cancer patient-derived organoids at low micromolar concentrations. Compound 1a effectively inhibits the growth of non-small-cell lung cancer and triple-negative breast cancer xenograft tumors, impedes the metastatic spread of breast cancer cells, and can be modified into an antibody-drug conjugate payload to achieve precise tumor delivery in mice. Identified by thermal proteome profiling, an important molecular target of 1a in cellulo is Girdin, a multifunctional adaptor protein that is overexpressed in cancer cells and unequivocally serves as a signaling hub for multiple pivotal oncogenic pathways. However, specific small-molecule inhibitors of Girdin have not yet been developed. Notably, 1a exhibits high binding affinity to Girdin with a Kd of 1.3 µM and targets the Girdin-linked EGFR/AKT/mTOR/STAT3 cancer-driving pathway, inhibiting cancer cell proliferation and metastatic activity. Our study reveals a potent Girdin-targeting anticancer compound and demonstrates that octahedral metal complexes constitute an untapped library of small-molecule inhibitors that can fit into the ligand-binding pockets of key oncoproteins.


Assuntos
Antineoplásicos , Irídio , Metano , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Irídio/química , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metano/análogos & derivados , Metano/química , Metano/farmacologia , Proteínas dos Microfilamentos/metabolismo , Metástase Neoplásica , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino
5.
Development ; 149(10)2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35502748

RESUMO

Adventitious roots (ARs) are an important type of plant root and display high phenotypic plasticity in response to different environmental stimuli. It is known that photoreceptors inhibit darkness-induced hypocotyl adventitious root (HAR) formation by directly stabilizing Aux/IAA proteins. In this study, we further report that phytochrome-interacting factors (PIFs) plays a central role in HAR initiation by simultaneously inducing the expression of genes involved in auxin biosynthesis, auxin transport and the transcriptional control of root primordium initiation. We found that, on the basis of their activity downstream of phytochrome, PIFs are required for darkness-induced HAR formation. Specifically, PIFs directly bind to the promoters of some genes involved in root formation, including auxin biosynthesis genes YUCCA2 (YUC2) and YUC6, the auxin influx carrier genes AUX1 and LAX3, and the transcription factors WOX5/7 and LBD16/29, to activate their expression. These findings reveal a previously uncharacterized transcriptional regulatory network underlying HAR formation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Hipocótilo/genética , Hipocótilo/metabolismo , Ácidos Indolacéticos/metabolismo , Fitocromo/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
6.
Development ; 149(16)2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35899600

RESUMO

Phosphatidylinositol (PI) 4,5-bisphosphate (PIP2) is involved in many biological functions. However, the mechanisms of PIP2 in collective cell migration remain elusive. This study highlights the regulatory role of cytidine triphosphate synthase (CTPsyn) in collective border cell migration through regulating the asymmetrical distribution of PIP2. We demonstrated that border cell clusters containing mutant CTPsyn cells suppressed migration. CTPsyn was co-enriched with Actin at the leading edge of the Drosophila border cell cluster where PIP2 was enriched, and this enrichment depended on the CTPsyn activity. Genetic interactions of border cell migration were found between CTPsyn mutant and genes in PI biosynthesis. The CTPsyn reduction resulted in loss of the asymmetric activity of endocytosis recycling. Also, genetic interactions were revealed between components of the exocyst complex and CTPsyn mutant, indicating that CTPsyn activity regulates the PIP2-related asymmetrical exocytosis activity. Furthermore, CTPsyn activity is essential for RTK-polarized distribution in the border cell cluster. We propose a model in which CTPsyn activity is required for the asymmetrical generation of PIP2 to enrich RTK signaling through endocytic recycling in collective cell migration.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Carbono-Nitrogênio Ligases , Movimento Celular/genética , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo
7.
EMBO Rep ; 24(1): e55542, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36394374

RESUMO

The Zn content in cereal seeds is an important trait for crop production as well as for human health. However, little is known about how Zn is loaded to plant seeds. Here, through a genome-wide association study (GWAS), we identify the Zn-NA (nicotianamine) transporter gene ZmYSL2 that is responsible for loading Zn to maize kernels. High promoter sequence variation in ZmYSL2 most likely drives the natural variation in Zn concentrations in maize kernels. ZmYSL2 is specifically localized on the plasma membrane facing the maternal tissue of the basal endosperm transfer cell layer (BETL) and functions in loading Zn-NA into the BETL. Overexpression of ZmYSL2 increases the Zn concentration in the kernels by 31.6%, which achieves the goal of Zn biofortification of maize. These findings resolve the mystery underlying the loading of Zn into plant seeds, providing an efficient strategy for breeding or engineering maize varieties with enriched Zn nutrition.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Humanos , Zea mays/genética , Zea mays/metabolismo , Zinco/metabolismo , Melhoramento Vegetal , Sementes/genética , Proteínas de Membrana Transportadoras/genética
8.
Cell ; 141(2): 331-43, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20403327

RESUMO

A plethora of growth factors regulate keratinocyte proliferation and differentiation that control hair morphogenesis and skin barrier formation. Wavy hair phenotypes in mice result from naturally occurring loss-of-function mutations in the genes for TGF-alpha and EGFR. Conversely, excessive activities of TGF-alpha/EGFR result in hairless phenotypes and skin cancers. Unexpectedly, we found that mice lacking the Trpv3 gene also exhibit wavy hair coat and curly whiskers. Here we show that keratinocyte TRPV3, a member of the transient receptor potential (TRP) family of Ca(2+)-permeant channels, forms a signaling complex with TGF-alpha/EGFR. Activation of EGFR leads to increased TRPV3 channel activity, which in turn stimulates TGF-alpha release. TRPV3 is also required for the formation of the skin barrier by regulating the activities of transglutaminases, a family of Ca(2+)-dependent crosslinking enzymes essential for keratinocyte cornification. Our results show that a TRP channel plays a role in regulating growth factor signaling by direct complex formation.


Assuntos
Receptores ErbB/metabolismo , Cabelo/crescimento & desenvolvimento , Transdução de Sinais , Pele/crescimento & desenvolvimento , Canais de Cátion TRPV/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Cabelo/metabolismo , Humanos , Queratinócitos/metabolismo , Camundongos , Camundongos Knockout , Pele/metabolismo , Canais de Cátion TRPV/genética , Fator de Crescimento Transformador alfa/metabolismo
9.
J Allergy Clin Immunol ; 153(6): 1574-1585.e14, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38467291

RESUMO

BACKGROUND: The respiratory microbiome has been associated with the etiology and disease course of asthma. OBJECTIVE: We sought to assess the nasopharyngeal microbiota in children with a severe asthma exacerbation and their associations with medication, air quality, and viral infection. METHODS: A cross-sectional study was performed among children aged 2 to 18 years admitted to the medium care unit (MCU; n = 84) or intensive care unit (ICU; n = 78) with an asthma exacerbation. For case-control analyses, we matched all cases aged 2 to 6 years (n = 87) to controls in a 1:2 ratio. Controls were participants of either a prospective case-control study or a longitudinal birth cohort (n = 182). The nasopharyngeal microbiota was characterized by 16S-rRNA-gene sequencing. RESULTS: Cases showed higher Shannon diversity index (ICU and MCU combined; P = .002) and a distinct microbial community composition when compared with controls (permutational multivariate ANOVA R2 = 1.9%; P < .001). We observed significantly higher abundance of Staphylococcus and "oral" taxa, including Neisseria, Veillonella, and Streptococcus spp. and a lower abundance of Dolosigranulum pigrum, Corynebacterium, and Moraxella spp. (MaAsLin2; q < 0.25) in cases versus controls. Furthermore, Neisseria abundance was associated with more severe disease (ICU vs MCU MaAslin2, P = .03; q = 0.30). Neisseria spp. abundance was also related with fine particulate matter exposure, whereas Haemophilus and Streptococcus abundances were related with recent inhaled corticosteroid use. We observed no correlations with viral infection. CONCLUSIONS: Our results demonstrate that children admitted with asthma exacerbations harbor a microbiome characterized by overgrowth of Staphylococcus and "oral" microbes and an underrepresentation of beneficial niche-appropriate commensals. Several of these associations may be explained by (environmental or medical) exposures, although cause-consequence relationships remain unclear and require further investigations.


Assuntos
Asma , Microbiota , Nasofaringe , Humanos , Asma/microbiologia , Criança , Pré-Escolar , Masculino , Nasofaringe/microbiologia , Feminino , Adolescente , Estudos Transversais , Estudos de Casos e Controles , RNA Ribossômico 16S/genética , Progressão da Doença , Estudos Prospectivos , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação
10.
Lancet Oncol ; 25(2): 225-234, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38301690

RESUMO

BACKGROUND: Cancer incidence and mortality is increasing rapidly worldwide, with a higher cancer burden observed in the Asia-Pacific region than in other regions. To date, evidence-based modelling of radiotherapy demand has been based on stage data from high-income countries (HIC) that do not account for the later stage at presentation seen in many low-income and middle-income countries (LMICs). We aimed to estimate the current and projected demand and supply in megavoltage radiotherapy machines in the Asia-Pacific region, using a national income-group adjusted model. METHODS: Novel LMIC radiotherapy demand and outcome models were created by adjusting previously developed models that used HIC cancer staging data. These models were applied to the cancer case mix (ie, the incidence of each different cancer) in each LMIC in the Asia-Pacific region to estimate the current and projected optimal radiotherapy utilisation rate (ie, the proportion of cancer cases that would require radiotherapy on the basis of guideline recommendations), and to estimate the number of megavoltage machines needed in each country to meet this demand. Information on the number of megavoltage machines available in each country was retrieved from the Directory of Radiotherapy Centres. Gaps were determined by comparing the projected number of megavoltage machines needed with the number of machines available in each region. Megavoltage machine numbers, local control, and overall survival benefits were compared with previous data from 2012 and projected data for 2040. FINDINGS: 57 countries within the Asia-Pacific region were included in the analysis with 9·48 million new cases of cancer in 2020, an increase of 2·66 million from 2012. Local control was 7·42% and overall survival was 3·05%. Across the Asia-Pacific overall, the current optimal radiotherapy utilisation rate is 49·10%, which means that 4·66 million people will need radiotherapy in 2020, an increase of 1·38 million (42%) from 2012. The number of megavoltage machines increased by 1261 (31%) between 2012 and 2020, but the demand for these machines increased by 3584 (42%). The Asia-Pacific region only has 43·9% of the megavoltage machines needed to meet demand, ranging from 9·9-40·5% in LMICs compared with 67·9% in HICs. 12 000 additional megavoltage machines will be needed to meet the projected demand for 2040. INTERPRETATION: The difference between supply and demand with regard to megavoltage machine availability has continued to widen in LMICs over the past decade and is projected to worsen by 2040. The data from this study can be used to provide evidence for the need to incorporate radiotherapy in national cancer control plans and to inform governments and policy makers within the Asia-Pacific region regarding the urgent need for investment in this sector. FUNDING: The Regional Cooperative Agreement for Research, Development and Training Related to Nuclear Science and Technology for Asia and the Pacific (RCA) Regional Office (RCARP03).


Assuntos
Atenção à Saúde , Neoplasias , Humanos , Ásia/epidemiologia , Países em Desenvolvimento , Neoplasias/epidemiologia , Neoplasias/radioterapia
11.
Artigo em Inglês | MEDLINE | ID: mdl-39069827

RESUMO

The mitochondrial citrate shuttle, which relies on the solute carrier family 25 member 1 (SLC25A1), plays a pivotal role in transporting citrate from the mitochondria to the cytoplasm. This shuttle supports glycolysis, lipid biosynthesis, and protein acetylation. Previous research has primarily focused on Slc25a1 in pathological models, particularly high-fat diet (HFD)-induced obesity. However, the impact of Slc25a1 inhibition on nutrient metabolism under HFD remains unclear. To address this gap, we used zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus) to evaluate the effects of inhibiting Slc25a1. In zebrafish, we administered Slc25a1-specific inhibitors (CTPI-2) for four weeks, while Nile tilapia received intraperitoneal injections of dsRNA to knockdown slc25a1b for seven days. Inhibition of the mitochondrial citrate shuttle effectively protected zebrafish from HFD-induced obesity, hepatic steatosis, and insulin resistance. Notably, glucose tolerance was unaffected. Inhibition of Slc25a1 altered hepatic protein acetylation patterns, with decreased cytoplasmic acetylation and increased mitochondrial acetylation. Under HFD conditions, Slc25a1 inhibition promoted fatty acid oxidation and reduced hepatic triglyceride accumulation by deacetylating Cpt1a. Additionally, Slc25a1 inhibition triggered acetylation-induced inactivation of Pdhe1α, leading to a reduction in glucose oxidative catabolism. This was accompanied by enhanced glucose uptake and storage in zebrafish livers. Furthermore, Slc25a1 inhibition under HFD conditions activated the SIRT1/PGC1α pathway, promoting mitochondrial proliferation and enhancing oxidative phosphorylation for energy production. Our findings provide new insights into the role of non-histone protein acetylation via the mitochondrial citrate shuttle in the development of hepatic lipid deposition and hyperglycemia caused by HFD.

12.
J Biol Chem ; 299(10): 105220, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37660921

RESUMO

Pharmacological inhibition of mitochondrial fatty acid oxidation (FAO) has been clinically used to alleviate certain metabolic diseases by remodeling cellular metabolism. However, mitochondrial FAO inhibition also leads to mechanistic target of rapamycin complex 1 (mTORC1) activation-related protein synthesis and tissue hypertrophy, but the mechanism remains unclear. Here, by using a mitochondrial FAO inhibitor (mildronate or etomoxir) or knocking out carnitine palmitoyltransferase-1, we revealed that mitochondrial FAO inhibition activated the mTORC1 pathway through general control nondepressible 5-dependent Raptor acetylation. Mitochondrial FAO inhibition significantly promoted glucose catabolism and increased intracellular acetyl-CoA levels. In response to the increased intracellular acetyl-CoA, acetyltransferase general control nondepressible 5 activated mTORC1 by catalyzing Raptor acetylation through direct interaction. Further investigation also screened Raptor deacetylase histone deacetylase class II and identified histone deacetylase 7 as a potential regulator of Raptor. These results provide a possible mechanistic explanation for the mTORC1 activation after mitochondrial FAO inhibition and also bring light to reveal the roles of nutrient metabolic remodeling in regulating protein acetylation by affecting acetyl-CoA production.

13.
J Biol Chem ; 299(4): 103028, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36805339

RESUMO

The emergence of SARS-CoV-2, which is responsible for the COVID-19 pandemic, has highlighted the need for rapid characterization of viral mechanisms associated with cellular pathogenesis. Viral UTRs represent conserved genomic elements that contribute to such mechanisms. Structural details of most CoV UTRs are not available, however. Experimental approaches are needed to allow for the facile generation of high-quality viral RNA tertiary structural models, which can facilitate comparative mechanistic efforts. By integrating experimental and computational techniques, we herein report the efficient characterization of conserved RNA structures within the 5'UTR of the HCoV-OC43 genome, a lab-tractable model coronavirus. We provide evidence that the 5'UTR folds into a structure with well-defined stem-loops (SLs) as determined by chemical probing and direct detection of hydrogen bonds by NMR. We combine experimental base-pair restraints with global structural information from SAXS to generate a 3D model that reveals that SL1-4 adopts a topologically constrained structure wherein SLs 3 and 4 coaxially stack. Coaxial stacking is mediated by short linker nucleotides and allows SLs 1 to 2 to sample different cojoint orientations by pivoting about the SL3,4 helical axis. To evaluate the functional relevance of the SL3,4 coaxial helix, we engineered luciferase reporter constructs harboring the HCoV-OC43 5'UTR with mutations designed to abrogate coaxial stacking. Our results reveal that the SL3,4 helix intrinsically represses translation efficiency since the destabilizing mutations correlate with increased luciferase expression relative to wildtype without affecting reporter mRNA levels, thus highlighting how the 5'UTR structure contributes to the viral mechanism.


Assuntos
Regiões 5' não Traduzidas , Coronavirus Humano OC43 , RNA Viral , Coronavirus Humano OC43/genética , Luciferases/genética , Espalhamento a Baixo Ângulo , Difração de Raios X , RNA Viral/genética
14.
J Biol Chem ; 299(8): 104958, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37380083

RESUMO

Nitrogen (N) is an essential element for microbial growth and metabolism. The growth and reproduction of microorganisms in more than 75% of areas of the ocean are limited by N. Prochlorococcus is numerically the most abundant photosynthetic organism on the planet. Urea is an important and efficient N source for Prochlorococcus. However, how Prochlorococcus recognizes and absorbs urea still remains unclear. Prochlorococcus marinus MIT 9313, a typical Cyanobacteria, contains an ABC-type transporter, UrtABCDE, which may account for the transport of urea. Here, we heterologously expressed and purified UrtA, the substrate-binding protein of UrtABCDE, detected its binding affinity toward urea, and further determined the crystal structure of the UrtA/urea complex. Molecular dynamics simulations indicated that UrtA can alternate between "open" and "closed" states for urea binding. Based on structural and biochemical analyses, the molecular mechanism for urea recognition and binding was proposed. When a urea molecule is bound, UrtA undergoes a state change from open to closed surrounding the urea molecule, and the urea molecule is further stabilized by the hydrogen bonds supported by the conserved residues around it. Moreover, bioinformatics analysis showed that ABC-type urea transporters are widespread in bacteria and probably share similar urea recognition and binding mechanisms as UrtA from P. marinus MIT 9313. Our study provides a better understanding of urea absorption and utilization in marine bacteria.


Assuntos
Prochlorococcus , Água do Mar , Transportadores de Cassetes de Ligação de ATP/metabolismo , Prochlorococcus/metabolismo , Ureia/metabolismo , Água do Mar/microbiologia
15.
Oncologist ; 29(1): e15-e24, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37279780

RESUMO

BACKGROUND: Neoadjuvant trastuzumab/pertuzumab (HP) plus chemotherapy for HER2-positive breast cancer (BC) achieved promising efficacy. The additional cardiotoxicity still existed. Brecan study evaluated the efficacy and safety of neoadjuvant pegylated liposomal doxorubicin (PLD)/cyclophosphamide and sequential nab-paclitaxel based on HP (PLD/C/HP-nabP/HP). PATIENTS AND METHODS: Brecan was a single-arm phase II study. Eligible patients with stages IIA-IIIC HER2-positive BC received 4 cycles of PLD, cyclophosphamide, and HP, followed by 4 cycles of nab-paclitaxel and HP. Definitive surgery was scheduled after 21 days for patients completing treatment or experiencing intolerable toxicity. The primary endpoint was the pathological complete response (pCR). RESULTS: Between January 2020 and December 2021, 96 patients were enrolled. Ninety-five (99.0%) patients received 8 cycles of neoadjuvant therapy and all underwent surgery with 45 (46.9%) breast-conserving surgery and 51 (53.1%) mastectomy. The pCR was 80.2% (95%CI, 71.2%-87.0%). Four (4.2%) experienced left ventricular insufficiency with an absolute decline in LVEF (43%-49%). No congestive heart failure and ≥grade 3 cardiac toxicity occurred. The objective response rate was 85.4% (95%CI, 77.0%-91.1%), including 57 (59.4%) complete responses and 25 (26.0%) partial responses. The disease control rate was 99.0% (95%CI, 94.3%-99.8%). For overall safety, ≥grade 3 AEs occurred in 30 (31.3%) and mainly included neutropenia (30.2%) and asthenia (8.3%). No treatment-related deaths occurred. Notably, age of >30 (P = .01; OR = 5.086; 95%CI, 1.44-17.965) and HER2 IHC 3+ (P = .02; OR = 4.398; 95%CI, 1.286-15.002) were independent predictors for superior pCR (ClinicalTrials.gov Identifier NCT05346107). CONCLUSION: Brecan study demonstrated the encouraging safety and efficacy of neoadjuvant PLD/C/HP-nabP/HP, suggesting a potential therapeutic option in HER2-positive BC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Terapia Neoadjuvante/efeitos adversos , Receptor ErbB-2/uso terapêutico , Mastectomia , Resultado do Tratamento , Paclitaxel , Ciclofosfamida/uso terapêutico , Trastuzumab/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
16.
Anal Chem ; 96(28): 11383-11389, 2024 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-38946419

RESUMO

Apurinic/apyrimidinic endonuclease 1 (APE1), as a vital base excision repair enzyme, is essential for maintaining genomic integrity and stability, and its abnormal expression is closely associated with malignant tumors. Herein, we constructed an electrochemiluminescence (ECL) biosensor for detecting APE1 activity by combining nanoconfined ECL silver nanoclusters (Ag NCs) with X-shaped DNA recognizer-triggered cascade amplification. Specifically, the Ag NCs were prepared and confined in the glutaraldehyde-cross-linked chitosan hydrogel network using the one-pot method, resulting in a strong ECL response and exceptional stability in comparison with discrete Ag NCs. Furthermore, the self-assembled X-shaped DNA recognizers were designed for APE1 detection, which not only improved reaction kinetics due to the ordered arrangement of recognition sites but also achieved high sensitivity by utilizing the recognizer-triggered cascade amplification of strand displacement amplification (SDA) and DNAzyme catalysis. As expected, this biosensor achieved sensitive ECL detection of APE1 in the range of 1.0 × 10-3 U·µL-1 to 1.0 × 10-10 U·µL-1 with the detection limit of 2.21 × 10-11 U·µL-1, rendering it a desirable approach for biomarker detection.


Assuntos
Técnicas Biossensoriais , DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Técnicas Eletroquímicas , Medições Luminescentes , Nanopartículas Metálicas , Prata , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/análise , Prata/química , Humanos , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA/química , Limite de Detecção , DNA Catalítico/química , DNA Catalítico/metabolismo
17.
Anal Chem ; 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39127919

RESUMO

Multiple reaction monitoring (MRM) is a powerful and popular technique used for metabolite quantification in targeted metabolomics. Accurate and consistent quantitation of metabolites from the MRM data is essential for subsequent analyses. Here, we developed an automated tool, MRMQuant, for targeted metabolomic quantitation using high-throughput liquid chromatography-tandem mass spectrometry MRM data to provide users with an easy-to-use tool for accurate MRM data quantitation with minimal human intervention. This tool has many user-friendly functions and features to inspect and correct the quantitation results as required. MRMQuant possesses the following features to ensure accurate quantitation: (1) dynamic signal smoothing, (2) automatic deconvolution of coeluted peaks, (3) absolute quantitation via standard curves and/or internal standards, (4) visualized inspection and correction, (5) corrections applicable to multiple samples, and (6) batch-effect correction.

18.
BMC Med ; 22(1): 28, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38263021

RESUMO

BACKGROUND: Current hypertension guidelines recommend combination of an angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker with a calcium-channel blocker or thiazide diuretic as initial antihypertensive therapy in patients with monotherapy uncontrolled hypertension. However, to what extent these two different combinations are comparable in blood pressure (BP)-lowering efficacy and safety remains under investigation, especially in the Chinese population. We investigated the BP-lowering efficacy and safety of the amlodipine/benazepril and benazepril/hydrochlorothiazide dual therapies in Chinese patients. METHODS: In a multi-center, randomized, actively controlled, parallel-group trial, we enrolled patients with stage 1 or 2 hypertension from July 2018 to June 2021 in 20 hospitals and community health centers across China. Of the 894 screened patients, 560 eligible patients were randomly assigned to amlodipine/benazepril 5/10 mg (n = 282) or benazepril/hydrochlorothiazide 10/12.5 mg (n = 278), with 213 and 212 patients, respectively, who completed the study and had a valid repeat ambulatory BP recording during follow-up and were included in the efficacy analysis. The primary outcome was the change from baseline to 24 weeks of treatment in 24-h ambulatory systolic BP. Adverse events including symptoms and clinically significant changes in physical examinations and laboratory findings were recorded for safety analysis. RESULTS: In the efficacy analysis (n = 425), the primary outcome, 24-h ambulatory systolic BP reduction, was - 13.8 ± 1.2 mmHg in the amlodipine/benazepril group and - 12.3 ± 1.2 mmHg in the benazepril/hydrochlorothiazide group, with a between-group difference of - 1.51 (p = 0.36) mmHg. The between-group differences for major secondary outcomes were - 1.47 (p = 0.18) in 24-h diastolic BP, - 2.86 (p = 0.13) and - 2.74 (p = 0.03) in daytime systolic and diastolic BP, and - 0.45 (p = 0.82) and - 0.93 (p = 0.44) in nighttime systolic and diastolic BP. In the safety analysis (n = 560), the incidence rate of dry cough was significantly lower in the amlodipine/benazepril group than in the benazepril/hydrochlorothiazide group (5.3% vs 10.1%, p = 0.04). CONCLUSIONS: The amlodipine/benazepril and benazepril/hydrochlorothiazide dual therapies were comparable in ambulatory systolic BP lowering. The former combination, compared with the latter, had a greater BP-lowering effect in the daytime and a lower incidence rate of dry cough. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03682692. Registered on 18 September 2018.


Assuntos
Hipertensão , Hipotensão , Humanos , Anti-Hipertensivos , Anlodipino , Hidroclorotiazida , China , Tosse
19.
Eur Respir J ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117429

RESUMO

BACKGROUND: Recurrent respiratory tract infections (rRTIs) are a common reason for immunodiagnostic testing in children, which relies on serum antibody level measurements. However, because RTIs predominantly affect the respiratory mucosa, serum antibodies may inaccurately reflect local immune defences. We investigated antibody responses in saliva and their interplay with the respiratory microbiota in relation to RTI severity and burden in young children with rRTIs. METHODS: We conducted a prospective cohort study including 100 children aged <10 years with rRTIs, their family members, and healthy healthcare professionals. Total and polyreactive antibody concentrations were determined in serum and saliva (ELISA); respiratory microbiota composition (16S-rRNA-sequencing) and respiratory viruses (qPCR) were characterised in nasopharyngeal swabs. Proteomic analysis (Olink®) was performed on saliva and serum samples. RTI symptoms were monitored with a daily cell phone application and assessed using latent class analysis and negative binomial mixed models. RESULTS: Serum antibody levels were not associated with RTI severity. Strikingly, 28% of salivary antibodies and only 2% of serum antibodies displayed polyreactivity (p<0.001). Salivary polyreactive immunoglobulin A (IgA) was negatively associated with recurrent lower RTIs (aOR 0.80 [95% CI 0.67-0.94]) and detection of multiple respiratory viruses (aOR 0.76 [95% CI 0.61-0.96]). Haemophilus influenzae abundance was positively associated with RTI symptom burden (regression coefficient 0.07 [95% CI 0.02-0.12]). CONCLUSION: These results highlight the importance of mucosal immunity in RTI severity and burden and suggest that the level of salivary polyreactive IgA and H. influenzae abundance may serve as indicators of infection risk and severity in young children with rRTIs.

20.
Small ; 20(6): e2305052, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37798622

RESUMO

The rapid increase and spread of Gram-negative bacteria resistant to many or all existing treatments threaten a return to the preantibiotic era. The presence of bacterial polysaccharides that impede the penetration of many antimicrobials and protect them from the innate immune system contributes to resistance and pathogenicity. No currently approved antibiotics target the polysaccharide regions of microbes. Here, describe monolaurin-based niosomes, the first lipid nanoparticles that can eliminate bacterial polysaccharides from hypervirulent Klebsiella pneumoniae, are described. Their combination with polymyxin B shows no cytotoxicity in vitro and is highly effective in combating K. pneumoniae infection in vivo. Comprehensive mechanistic studies have revealed that antimicrobial activity proceeds via a multimodal mechanism. Initially, lipid nanoparticles disrupt polysaccharides, then outer and inner membranes are destabilized and destroyed by polymyxin B, resulting in synergistic cell lysis. This novel lipidic nanoparticle system shows tremendous promise as a highly effective antimicrobial treatment targeting multidrug-resistant Gram-negative pathogens.


Assuntos
Nanopartículas , Polimixina B , Polimixina B/farmacologia , Lipossomos/farmacologia , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Klebsiella pneumoniae , Polissacarídeos Bacterianos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla
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