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1.
J Am Heart Assoc ; : e034203, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023067

RESUMO

BACKGROUND: Vascular smooth muscle cell (VSMC) proliferation is involved in many types of arterial diseases, including neointima hyperplasia, in which Ca2+ has been recognized as a key player. However, the physiological role of Ca2+ release via inositol 1,4,5-trisphosphate receptors (IP3Rs) from endoplasmic reticulum in regulating VSMC proliferation has not been well determined. METHODS AND RESULTS: Both in vitro cell culture models and in vivo mouse models were generated to investigate the role of IP3Rs in regulating VSMC proliferation. Expression of all 3 IP3R subtypes was increased in cultured VSMCs upon platelet-derived growth factor-BB and FBS stimulation as well as in the left carotid artery undergoing intimal thickening after vascular occlusion. Genetic ablation of all 3 IP3R subtypes abolished endoplasmic reticulum Ca2+ release in cultured VSMCs, significantly reduced cell proliferation induced by platelet-derived growth factor-BB and FBS stimulation, and also decreased cell migration of VSMCs. Furthermore, smooth muscle-specific deletion of all IP3R subtypes in adult mice dramatically attenuated neointima formation induced by left carotid artery ligation, accompanied by significant decreases in cell proliferation and matrix metalloproteinase-9 expression in injured vessels. Mechanistically, IP3R-mediated Ca2+ release may activate cAMP response element-binding protein, a key player in controlling VSMC proliferation, via Ca2+/calmodulin-dependent protein kinase II and Akt. Loss of IP3Rs suppressed cAMP response element-binding protein phosphorylation at Ser133 in both cultured VSMCs and injured vessels, whereas application of Ca2+ permeable ionophore, ionomycin, can reverse cAMP response element-binding protein phosphorylation in IP3R triple knockout VSMCs. CONCLUSIONS: Our results demonstrated an essential role of IP3R-mediated Ca2+ release from endoplasmic reticulum in regulating cAMP response element-binding protein activation, VSMC proliferation, and neointima formation in mouse arteries.

3.
Infect Drug Resist ; 17: 1827-1838, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741942

RESUMO

Objective: This study aimed to assess the impact of colonization status on the outcomes of Acinetobacter spp. bloodstream infection (BSI) and investigate the homology and within-host evolution between colonizing and bloodstream carbapenem-resistant Acinetobacter spp. (CRA) to inform antibiotic therapeutic decisions. Methods: We analyzed clinical outcomes of 46 hematological patients with Acinetobacter spp. BSI and performed whole-genome sequencing on the remaining CRA isolates. Results: Among the patients, 39.1% (n=18) had prior Acinetobacter spp. colonization. Colonized patients had higher rates of polymicrobial BSI (50.0% vs 21.4%, P=0.044) and CRA BSI (72.2% vs 17.9%, P<0.001), resulting in elevated inflammatory markers and increased 30-day mortality. Each of the eight pairs of the remaining respiratory colonizing and bloodstream CRA strains belonged to the same genomospecies. Each pair exhibited definitive agreement in at least 21 of the 22 most representative antibiotic susceptibility tests. The minimum spanning tree based on multilocus sequence typing (MLST) and phylogenetic trees based on MLST and single nucleotide polymorphism (SNP) all indicated that each pair shared the same minimum branch. Very few non-synonymous SNPs in genic regions were identified during the transition from respiratory colonization to bloodstream infection, with minimal changes in virulence genes. Homology analysis suggested that CRA BSI originated from colonizing isolates in the respiratory tract. Conclusion: Strict infection control measures are needed to manage Acinetobacter spp. colonisation in hematological patients. Appropriate empirical therapy can be administered for suspected CRA BSI based on the antimicrobial minimum inhibitory concentration of CRA colonising the respiratory tract.

5.
Microbiology (Reading) ; 170(3)2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38568202

RESUMO

Understanding the evolution of antibiotic resistance is important for combating drug-resistant bacteria. In this work, we investigated the adaptive response of Pseudomonas aeruginosa to ciprofloxacin. Ciprofloxacin-susceptible P. aeruginosa ATCC 9027, CIP-E1 (P. aeruginosa ATCC 9027 exposed to ciprofloxacin for 14 days) and CIP-E2 (CIP-E1 cultured in antibiotic-free broth for 10 days) were compared. Phenotypic responses including cell morphology, antibiotic susceptibility, and production of pyoverdine, pyocyanin and rhamnolipid were assessed. Proteomic responses were evaluated using comparative iTRAQ labelling LC-MS/MS to identify differentially expressed proteins (DEPs). Expression of associated genes coding for notable DEPs and their related regulatory genes were checked using quantitative reverse transcriptase PCR. CIP-E1 displayed a heterogeneous morphology, featuring both filamentous cells and cells with reduced length and width. By contrast, although filaments were not present, CIP-E2 still exhibited size reduction. Considering the MIC values, ciprofloxacin-exposed strains developed resistance to fluoroquinolone antibiotics but maintained susceptibility to other antibiotic classes, except for carbapenems. Pyoverdine and pyocyanin production showed insignificant decreases, whereas there was a significant decrease in rhamnolipid production. A total of 1039 proteins were identified, of which approximately 25 % were DEPs. In general, there were more downregulated proteins than upregulated proteins. Noted changes included decreased OprD and PilP, and increased MexEF-OprN, MvaT and Vfr, as well as proteins of ribosome machinery and metabolism clusters. Gene expression analysis confirmed the proteomic data and indicated the downregulation of rpoB and rpoS. In summary, the response to CIP involved approximately a quarter of the proteome, primarily associated with ribosome machinery and metabolic processes. Potential targets for bacterial interference encompassed outer membrane proteins and global regulators, such as MvaT.


Assuntos
Ciprofloxacina , Infecções por Pseudomonas , Humanos , Ciprofloxacina/farmacologia , Pseudomonas aeruginosa/genética , Cromatografia Líquida , Proteômica , Piocianina , Espectrometria de Massas em Tandem , Antibacterianos/farmacologia
6.
Cell Mol Life Sci ; 81(1): 42, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217709

RESUMO

Neprilysin (NEP) is an emerging biomarker for various diseases including heart failure (HF). However, major inter-assay inconsistency in the reported concentrations of circulating NEP and uncertainty with respect to its correlations with type and severity of disease are in part attributed to poorly characterized antibodies supplied in commercial ELISA kits. Validated antibodies with well-defined binding footprints are critical for understanding the biological and clinical context of NEP immunoassay data. To achieve this, we applied in silico epitope prediction and rational peptide selection to generate monoclonal antibodies (mAbs) against spatially distant sites on NEP. One of the selected epitopes contained published N-linked glycosylation sites at N285 and N294. The best antibody pair, mAb 17E11 and 31E1 (glycosylation-sensitive), were characterized by surface plasmon resonance, isotyping, epitope mapping, and western blotting. A validated two-site sandwich NEP ELISA with a limit of detection of 2.15 pg/ml and working range of 13.1-8000 pg/ml was developed with these mAbs. Western analysis using a validated commercial polyclonal antibody (PE pAb) and our mAbs revealed that non-HF and HF plasma NEP circulates as a heterogenous mix of moieties that possibly reflect proteolytic processing, post-translational modifications and homo-dimerization. Both our mAbs detected a ~ 33 kDa NEP fragment which was not apparent with PE pAb, as well as a common ~ 57-60 kDa moiety. These antibodies exhibit different affinities for the various NEP targets. Immunoassay results are dependent on NEP epitopes variably detected by the antibody pairs used, explaining the current discordant NEP measurements derived from different ELISA kits.


Assuntos
Anticorpos Monoclonais , Insuficiência Cardíaca , Humanos , Epitopos , Neprilisina/metabolismo , Ensaio de Imunoadsorção Enzimática , Imunoensaio/métodos
8.
J Infect Chemother ; 30(7): 608-615, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38215820

RESUMO

INTRODUCTION: Limited experience exists with ceftazidime-avibactam (CAZ-AVI) in treating bacteremia caused by carbapenem-resistant Enterobacterales (CRE) and Pseudomonas aeruginosa (CRPA) in hematological patients. METHODS: We performed a single-center, retrospective, observational study including patients who received CAZ-AVI for bacteremia due to CRE or CRPA between 2018 and 2022. The primary outcome was 30-day survival. We conducted a multivariable analysis to identify predictors of survival. RESULTS: 56 patients were included and 57 (41 CRE and 16 CRPA) strains were isolated. 35 strains produced carbapenemase, including 25 metallo-beta-lactamase (MBL) and 10 serine-beta-lactamase. 48 patients (85.7 %) received combination therapy. All patients with MBL-CRE bacteremia (n = 24) received combination therapy with aztreonam (AZT). The susceptibility rates to CAZ-AVI were only 26.8 % (11/41) in CRE and 80.0 % (8/10) in CRPA. The 30-day survival rates were 85.0 % (34/40) in the CRE group and 81.3 % (13/16) in the CRPA group. In patients with MBL-CRE bacteremia, the 30-day survival was as high as 91.7 % (22/24) due to combination with AZT. Ceftazidime did not influence the activity of aztreonam-avibactam against MBL-CRE in-vitro. Multivariable cox analysis revealed neutropenia >14 days (P = 0.002, HR: 34.483, 95%CI: 3.846-333.333) and a higher Pitt bacteremia score (P = 0.005, HR: 2.074, 95%CI: 1.253-3.436) were risk factors for 30-day survival. CONCLUSIONS: CAZ-AVI is highly effective in treating bacteremia due to CRPA and serine-beta-lactamase CRE. The combination of avibactam with AZT is highly effective in treating bacteremia due to AZT-resistant MBL producers.


Assuntos
Antibacterianos , Compostos Azabicíclicos , Bacteriemia , Ceftazidima , Combinação de Medicamentos , Pseudomonas aeruginosa , Humanos , Ceftazidima/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Estudos Retrospectivos , Feminino , Compostos Azabicíclicos/uso terapêutico , Pessoa de Meia-Idade , Masculino , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Idoso , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Adulto , Testes de Sensibilidade Microbiana , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , beta-Lactamases/metabolismo , Quimioterapia Combinada/métodos , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/mortalidade , Infecções por Pseudomonas/microbiologia
9.
Clin Infect Dis ; 78(3): 518-525, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-37795577

RESUMO

BACKGROUND: Several studies have suggested that short-course antibiotic therapy was effective in Pseudomonas aeruginosa (PA) bloodstream infections (BSI) in immunocompetent patients. But similar studies in patients with hematological malignancies were rare. METHODS: This cohort study included onco-hematology patients at 2 hematology centers in China. Inverse probability of treatment weighting was used to balance the confounding factors. Multivariate regression model was used to evaluate the effect of short-course antibiotic therapy on clinical outcomes. RESULTS: In total, 434 patients met eligibility criteria (short-course, 7-11 days, n = 229; prolonged, 12-21 days, n = 205). In the weighted cohort, the univariate and multivariate analysis indicated that short course antibiotic therapy had similar outcomes to the prolonged course. The recurrent PA infection at any site or mortality within 30 days of completing therapy occurred in 8 (3.9%) patients in the short-course group and in 10 (4.9%) in the prolonged-course group (P = .979). The recurrent infection within 90 days occurred in 20 (9.8%) patients in the short-course group and in 13 (6.3%) patients in the prolonged-course group (P = .139), and the recurrent fever within 7 days occurred in 17 (8.3%) patients in the short-course group and in 15 (7.4%) in the prolonged-course group (P = .957). On average, patients who received short-course antibiotic therapy spent 3.3 fewer days in the hospital (P < .001). CONCLUSIONS: In the study, short-course therapy was non-inferior to prolonged-course therapy in terms of clinical outcomes. However, due to its biases and limitations, further prospective randomized controlled trials are needed to generalize our findings.


Assuntos
Bacteriemia , Neutropenia Febril , Hematologia , Infecções por Pseudomonas , Sepse , Humanos , Pseudomonas aeruginosa , Estudos de Coortes , Antibacterianos/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Neutropenia Febril/complicações , Neutropenia Febril/tratamento farmacológico , Sepse/tratamento farmacológico , Bacteriemia/tratamento farmacológico
10.
Mol Cancer ; 22(1): 206, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38093346

RESUMO

BACKGROUND: Social behaviors such as altruism, where one self-sacrifices for collective benefits, critically influence an organism's survival and responses to the environment. Such behaviors are widely exemplified in nature but have been underexplored in cancer cells which are conventionally seen as selfish competitive players. This multidisciplinary study explores altruism and its mechanism in breast cancer cells and its contribution to chemoresistance. METHODS: MicroRNA profiling was performed on circulating tumor cells collected from the blood of treated breast cancer patients. Cancer cell lines ectopically expressing candidate miRNA were used in co-culture experiments and treated with docetaxel. Ecological parameters like relative survival and relative fitness were assessed using flow cytometry. Functional studies and characterization performed in vitro and in vivo include proliferation, iTRAQ-mass spectrometry, RNA sequencing, inhibition by small molecules and antibodies, siRNA knockdown, CRISPR/dCas9 inhibition and fluorescence imaging of promoter reporter-expressing cells. Mathematical modeling based on evolutionary game theory was performed to simulate spatial organization of cancer cells. RESULTS: Opposing cancer processes underlie altruism: an oncogenic process involving secretion of IGFBP2 and CCL28 by the altruists to induce survival benefits in neighboring cells under taxane exposure, and a self-sacrificial tumor suppressive process impeding proliferation of altruists via cell cycle arrest. Both processes are regulated concurrently in the altruists by miR-125b, via differential NF-κB signaling specifically through IKKß. Altruistic cells persist in the tumor despite their self-sacrifice, as they can regenerate epigenetically from non-altruists via a KLF2/PCAF-mediated mechanism. The altruists maintain a sparse spatial organization by inhibiting surrounding cells from adopting the altruistic fate via a lateral inhibition mechanism involving a GAB1-PI3K-AKT-miR-125b signaling circuit. CONCLUSIONS: Our data reveal molecular mechanisms underlying manifestation, persistence and spatial spread of cancer cell altruism. A minor population behave altruistically at a cost to itself producing a collective benefit for the tumor, suggesting tumors to be dynamic social systems governed by the same rules of cooperation in social organisms. Understanding cancer cell altruism may lead to more holistic models of tumor evolution and drug response, as well as therapeutic paradigms that account for social interactions. Cancer cells constitute tractable experimental models for fields beyond oncology, like evolutionary ecology and game theory.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Altruísmo , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , Neoplasias da Mama/genética
11.
Chin Neurosurg J ; 9(1): 31, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957765

RESUMO

BACKGROUND: Acute normovolemic hemodilution (ANH) was first introduced in glioblastoma surgery, and its role in reducing allogeneic blood transfusion was investigated in this study. METHODS: This study enrolled supratentorial glioblastoma patients who received total resection. In the ANH group, the patients were required to draw blood before the operation, and the blood will be transfused back to the patient during the operation. The association between ANH and clinical features was investigated. RESULTS: Sixty supratentorial glioblastoma patients were enrolled in this study, 25 patients were allocated in the ANH group, and another 35 patients were included in the control group. ANH dramatically reduced the need for allogeneic blood transfusion (3 [12%] vs 12 [34.3%], P = 0.049), and the blood transfusion per total of patients was dramatically decreased by the application of ANH (0.40 ± 1.15 units vs 1.06 ± 1.59 units, P = 0.069). Furthermore, ANH also markedly reduced the requirement of fresh frozen plasma (FFP) transfusion (2 [8%] vs 11 [31.4%], P = 0.030) and the volume of FFP transfusion per total of patients (32.00 ± 114.46 mL vs 115.71 ± 181.00 mL, P = 0.033). The complication rate was similar between the two groups. CONCLUSIONS: ANH was a safe and effective blood conservation technique in glioblastoma surgery.

12.
BMC Infect Dis ; 23(1): 796, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964192

RESUMO

PURPOSE: This study investigated the clinical and antimicrobial characteristics of Acinetobacter spp. bloodstream infection (BSI) in hematological patients. Risk factors for 30-day mortality and carbapenem-resistant Acinetobacter spp. (CRA) BSI acquisition were also identified. METHODS: We reviewed forty hematological patients with Acinetobacter spp. BSI in a large Chinese blood disease hospital between 2013 and 2022. The remaining CRA isolates were subjected to whole-genome sequencing. RESULTS: The 30-day mortality rate was high at 35%. Hematological patients with Acinetobacter spp. BSI often presented with severe conditions and co-infections at multiple sites. All strains were colistin-susceptible and 40.0% were CR. Multivariate analysis identified several risk factors associated with CRA BSI acquisition, including previous exposure to carbapenems within 30 days and CRA colonization. Very severe aplastic anaemia, tetracycline-resistant Acinetobacter spp. BSI, and unresolved neutropenia after infection were closely associated with 30-day mortality. Non-survivors often presented with higher median PCT and CRP levels and severe complications, such as intracranial infection, cardiac dysfunction, respiratory failure, and severe sepsis or septic shock. Our study also identified inappropriate empirical antibiotic therapy as an independent predictor of 30-day mortality (OR: 11.234, 95% CI: 1.261-20.086, P = 0.030). This study was the first to report A. oleivorans as a human pathogen, and to identify its unique oxacillinase, OXA-325. CONCLUSION: An environment-originated non-pathogenic species can become pathogenic when the body's immunity is compromised. Our results also highlighted the importance of improving neutropenia after infection, treating severe organ dysfunction, and administering appropriate empirical antibiotic therapy to reduce mortality in this patient population.


Assuntos
Infecções por Acinetobacter , Acinetobacter , Bacteriemia , Infecção Hospitalar , Neutropenia , Sepse , Humanos , Infecções por Acinetobacter/epidemiologia , Bacteriemia/epidemiologia , Infecção Hospitalar/epidemiologia , Sepse/tratamento farmacológico , Antibacterianos/uso terapêutico , Estudos Retrospectivos
13.
J Neuroinflammation ; 20(1): 261, 2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-37953259

RESUMO

BACKGROUND: Subarachnoid hemorrhage (SAH) causes significant long-term neurocognitive dysfunction, which is associated with hippocampal neuroinflammation. Growing evidences have shown that astrocytes played a significant role in mediating neuroinflammation. Recently, in vivo reprogramming of astrocytes to neurons by NeuroD1 or PTBP1 administration has generated a lot of interests and controversies. While the debates centered on the source of neurogenesis, no attention has been paid to the changes of the astrocytes-mediated neuroinflammation and its impact on endogenous neurogenesis after NeuroD1 administration. METHODS: 80 adult male C57BL/6 mice were used in this study. SAH was established by pre-chiasmatic injection of 100 µl blood. AAV-NeuroD1-GFP virus was injected to the hippocampus 3 day post-SAH. Neurocognitive function, brain water content, in vivo electrophysiology, Golgi staining, western blot and immunofluorescent staining were assessed at day 14 post-virus injection. RESULTS: NeuroD1 administration markedly attenuated reactive astrocytes-mediated neuroinflammation by reversing neurotoxic A1 astrocytes transformation, decreasing the secretion of neuroinflammatory cytokines, and reducing the activation of harmful microglia. NeuroD1 treatment significantly reversed the brain-blood barrier impairment and promoted the release of neurotrophic factors pleiotrophin (PTN), all of which contributed to the improvement of cellular microenvironment and made it more suitable for neurogenesis. Interestingly, besides neurogenesis in the hippocampus from cells transfected with NeuroD1 at the early phase of SAH, NeuroD1 administration significantly boosted the endogenous neurogenesis at the late phase of SAH, which likely benefited from the improvement of the neuroinflammatory microenvironment. Functionally, NeuroD1 treatment significantly alleviated neurocognitive dysfunction impaired by SAH. CONCLUSIONS: NeuroD1 significantly promoted neurofunctional recovery by attenuating reactive astrocytes-mediated neuroinflammation and boosting neurogenesis decimated by SAH. Specifically, NeuroD1 efficiently converted transfected cells, most likely astrocytes, to neurons at the early phase of SAH, suppressed astrocytes-mediated neuroinflammation and boosted endogenous neurogenesis at the late phase of SAH.


Assuntos
Doenças Neuroinflamatórias , Hemorragia Subaracnóidea , Camundongos , Animais , Masculino , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Camundongos Endogâmicos C57BL , Encéfalo , Neurogênese/fisiologia
14.
Adv Biol (Weinh) ; : e2300452, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794608

RESUMO

Triptolide (TPL), a natural product extracted from Tripterygium wilfordii Hook F, exerts potential anti-cancer activity. Studies have shown that TPL is involved in multiple cellular processes and signal pathways; however, its pharmaceutical activity in human colorectal cancer (CRC) as well as the underlying molecular mechanism remain elusive. In this study, the effects of TPL on HCT116 human colon cancer cells and CCD841 human colon epithelial cells are first evaluated. Next, the protein targets of TPL in HCT116 cells are identified through an activity-based protein profiling approach. With subsequent in vitro experiments, the mode of action of TPL in HCT116 cells is elucidated. As a result, TPL is found to selectively inhibit HCT116 cell viability and migration. A total of 54 proteins are identified as the targets of TPL in HCT116 cells, among which, Annexin A1 (ANXA1) and Peroxiredoxin I/II (Prdx I/II) are picked out for further investigation due to their important role in CRC. The interaction between TPL and ANXA1 or Prdx I is confirmed, and it is discovered that TPL exerts inhibitory effect against HCT116 cells through binding to ANXA1 and Prdx I. The study reinforces the potential of TPL in the CRC therapy, and provides novel therapeutic targets for the treatment of CRC.

15.
Biotechnol Biofuels Bioprod ; 16(1): 147, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789404

RESUMO

BACKGROUND: Alcohol is a good and environment-friendly fuel that can be microbially produced, capable of eliminating many of the limitations of the present-day fossil fuels. However, the inherent toxic nature of alcohols to the microbial cells leads to end-product inhibition that limits large-scale alcohol production by fermentation. Fundamental knowledge about the stress responses of microorganisms to alcohols would greatly facilitate to improve the microbial alcohol tolerance. The current study elucidates and compares the changes in the membrane proteome of Escherichia coli in response to a range of alcohols. RESULTS: Although alcohol toxicity increased exponentially with alcohol chain length (2-6 carbon), similar stress responses were observed in the inner and outer membrane proteome of E. coli in the presence of 2-, 4- and 6-carbon alcohols at the MIC50. This pertains to: (1) increased levels of inner membrane transporters for uptake of energy-producing metabolites, (2) reduced levels of non-essential proteins, associated with anaerobic, carbon starvation and osmotic stress, for energy conservation, (3) increased levels of murein degrading enzymes (MltA, EmtA, MliC and DigH) promoting cell elongation and 4) reduced levels of most outer membrane ß-barrel proteins (LptD, FadL, LamB, TolC and BamA). Major outer membrane ß-barrel protein OmpC, which is known to contribute to ethanol tolerance and membrane integrity, was notably reduced by alcohol stress. While LPS is important for OmpC trimerisation, LPS release by EDTA did not lower OmpC levels. This suggests that LPS release, which is reported under alcohol stress, does not contribute to the reduced levels of OmpC in the presence of alcohol. CONCLUSIONS: Since alcohol primarily targets the integrity of the membrane, maintenance of outer membrane OmpC levels in the presence of alcohol might help in the survival of E. coli to higher alcohol concentrations. The study provides important information about the membrane protein responses of E. coli to a range of alcohols, which can be used to develop targeted strategies for increased microbial alcohol tolerance and hence bioalcohol production.

16.
Proteome Sci ; 21(1): 15, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770917

RESUMO

BACKGROUND: Pseudomonas aeruginosa is well known for its intrinsic ability to resist a wide range of antibiotics, thus complicates treatment. Thus, understanding the response of the pathogen to antibiotics is important for developing new therapies. In this study, proteomic response of P. aeruginosa to the commonly used anti-pseudomonas antibiotics, ceftazidime (Caz) and meropenem (Mem) was investigated. METHODS: P. aeruginosa ATCC 9027, an antibiotic-susceptible strain, was exposed to sub-MIC values of antibiotics either Caz or Mem for 14 days to obtain E1 strains and then cultured in antibiotic-free environments for 10 days to obtain E2 strains. Proteomes of the initial and E1, E2 strains were identified and comparatively analyzed using isobaric tags for relative and absolute quantitation (iTRAQ) in cooperation with nano LC-MS/MS. Noted up and down-regulated proteins were confirmed with quantitative reverse transcriptase PCR (qRT-PCR). RESULTS: Overall, 1039 and 1041 proteins were identified in Caz and Mem-exposed strains, respectively. Upon antibiotic exposure, there were 7-10% up-regulated (Caz: 71, Mem: 85) and down-regulated (Caz: 106, Mem: 69) proteins (1.5-fold change cut-off). For both Caz and Mem, the DEPs were primarily the ones involved in metabolic process, membrane, virulence, protein synthesis, and antibiotic resistance in which proteins involved in antibiotics resistance tended to be up-regulated while proteins involved in protein synthesis and metabolic process were down-regulated. Noted proteins included beta-lactamase AmpC which was up-regulated and OprD which was down-regulated in both the antibiotic-exposed strains. Besides, biofilm formation related proteins TssC1 and Hcp1 in Caz- exposed strains and the membrane/ periplasmic proteins Azu and PagL in Mem-exposed strains were found significantly down-regulated. qRT-PCR results confirmed the expression change of AmpC, Hcp1 and OprD proteins. CONCLUSION: Exposure of Pseudomonas aeruginosa to sub-MIC values of Caz and Mem resulted in around 10% change in its proteome. Not only proteins with confirmed roles in antibiotic resistance mechanisms changed their expression but also virulence- associated proteins. Both Caz and Mem response involved up-regulation of AmpC and down-regulation of OprD. While TssC1 and Hcp1 were responsible for Caz response, Azu and PagL were more likely involved in Mem response.

17.
Mol Cell Proteomics ; 22(9): 100627, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37532177

RESUMO

As the first in-person Asia Oceania Human Proteomics Organization (AOHUPO) congress since 2018, the 11th AOHUPO congress was an opportune time for the research community to reconnect and to renew friendships after the long period of restricted travel due to the global pandemic. Moreover, this congress was a great opportunity for the many AO regional proteomics and mass spectrometry scientists to meet in Singapore to exchange ideas and to present their latest findings. Cohosted by the Singapore Society for Mass Spectrometry and the Malaysian Proteomics Society and held in conjunction with the seventh Asia Oceania Agricultural Proteomics Organization Congress and Singapore Society for Mass Spectrometry 2023, the meeting featured both human and agricultural proteomics. Over five hundred scientists from the AO region converged on the MAX Atria @ Singapore EXPO, Changi, Singapore from May 8 to 10 for the main congress. The diverse program was made up of 64 invited speakers and panellists for seven plenary lectures, 27 concurrent symposia, precongress and postcongress workshops, and 174 poster presentations. The AOHUPO society were able to celebrate not only their 20th anniversary but also the outstanding academic research from biological and agricultural proteomics and related 'omics fields being conducted across the Asia-Oceania region.


Assuntos
Proteoma , Proteômica , Humanos , Ásia , Proteômica/métodos , Espectrometria de Massas , Oceania
18.
Protein Sci ; 32(10): e4761, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37593853

RESUMO

The pupal cuticle protein from Aedes aegypti (AaPC) inhibits dengue virus (DENV) infection; however, the underlying mechanism of this inhibition remains unknown. Here, we report that AaPC is an intrinsically disordered protein and interacts with domain I/II of the DENV envelope protein via residues Asp59, Asp61, Glu71, Asp73, Ser75, and Asp80. AaPC can directly bind to and cause the aggregation of DENV, which in turn blocks virus infection during the virus-cell fusion stage. AaPC may also influence viral recognition and attachment by interacting with human immune receptors DC-SIGN and CD4. These findings enhance our understanding of the role of AaPC in mitigating viral infection and suggest that AaPC is a potential target for developing inhibitors or antibodies to control dengue virus infection.


Assuntos
Aedes , Vírus da Dengue , Dengue , Animais , Humanos , Vírus da Dengue/fisiologia , Pupa , Mosquitos Vetores
19.
Antimicrob Resist Infect Control ; 12(1): 66, 2023 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-37422680

RESUMO

BACKGROUND: Neutropenic children with hematological diseases were associated with higher morbidity of carbapenem-resistant enterobacteriaceae (CRE) blood-stream infection (BSI) or colonization. But it was still murky regarding clinical characteristics, antimicrobial susceptibility, and outcomes of CRE-BSI in these patients. We aimed to identify the potential risk factors for subsequent bacteremia and clinical outcome caused by CRE-BSI. METHODS: Between 2008 and 2020, 2,465 consecutive neutropenic children were enrolled. The incidence and characteristics of CRE-BSI were explored in CRE-colonizers versus non-colonizers. Survival analysis was performed and risk factors for CRE-BSI and 30-day mortality were evaluated. RESULTS: CRE-carriers were identified in 59/2465 (2.39%) neutropenic children and19/59 (32.2%) developed CRE-BSI, while 12/2406 (0.5%) of non-carriers developed CRE-BSI (P < 0.001). The 30-day survival probability was significantly lower in patients with CRE-BSI than in non-BSI (73.9% vs. 94.9%, P = 0.050). Moreover, the 30-day survival probability of patients with CRE-BSI was also poorer in CRE-carriers versus non-carriers (49.7% vs. 91.7%, P = 0.048). Tigecycline and amikacin exhibited satisfactory antimicrobial activity against all isolated strains. Fluoroquinolone sensitivity was lower in E. coli (26.3%) strains versus satisfactory susceptibility of E. cloacae and other CRE-strains (91.2%). CRE-BSI accompanying intestinal mucosal damage were independent risk factors for 30-day survival probability (both P < 0.05), while combined antibiotic therapy and longer duration of neutropenia were more prone to developed CRE-BSI (P < 0.05). CONCLUSION: CRE-colonizers were prone to subsequent BSI and CRE-BSI was regarded as an independent predictor predisposing to high mortality in neutropenic children. Moreover, individualized antimicrobial therapy should be adopted due to different features of patients with separate CRE strains.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Doenças Hematológicas , Sepse , Humanos , Criança , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/epidemiologia , Escherichia coli , Sepse/epidemiologia , Doenças Hematológicas/complicações
20.
Zookeys ; 1152: 1-8, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37235069

RESUMO

A new whitefly species, Aleurolobusrutaesp. nov., collected on Murrayaexotica (Sapindales, Rutaceae) leaves in the Maolan National Nature Reserve, Guizhou, China, is described and illustrated. Some of the individuals were infected with Aschersoniaplacenta, an entomopathogenic fungus. The insect is circular in shape and characterized by a very wide submarginal region, and the submarginal furrow is almost continuous, with only a small break at the caudal furrow. Anterior and posterior marginal setae are absent, but setae are present on the 8th abdominal segment. Thoracic and caudal tracheal folds are discernible.

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