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1.
Cell Death Discov ; 10(1): 392, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39223142

RESUMO

Metabolic reprogramming sustains malignant head and neck squamous cell carcinoma (HNSCC) to overcome stressful microenvironments, and increased glutamine uptake is a common metabolic hallmark in cancers. Since metabolic reprogramming has been recognized as a new therapeutic target for tumor cells, understanding the regulatory axis of glutamine uptake in HNSCC and its potential downstream effects in its pathogenesis of HNSCC would be incredibly beneficial. Bioinformatic analysis of the Cancer Genome Atlas (TCGA)-HNSCC dataset and RNAseq analysis performed on HNSCC indicated that SLC1A5 was the most dysregulated transporter among the seven homologous glutamate or neutral amino acid transporters in the SLC1A family. To further clarify the role of SLC1A5 in HNSCC, we knocked down SLC1A5 expression. This knockdown decelerated cell growth, induced G0/G1 arrest, diminished tumorigenicity, and increased cleavage caspase3, LC3B, and intracellular Fe2+. Inhibitors against apoptosis, autophagy, or ferroptosis rescued the cell viability repressed by SLC1A5 knockdown. SLC1A5 knockdown also suppressed glutamine uptake, enhanced oxidative stress, and increased sensitivity to cisplatin. CRISPR/dCas9-mediated SLC1A5 induction conferred cisplatin resistance and reduced apoptosis, autophagy, and ferroptosis. Reporter assays and western blot data demonstrated that miR-125b-5p targets and attenuates SLC1A5, while the si-NEAT1 increases miR-125b-5p expression. Analysis of the TCGA-HNSCC databases showed concordant upregulation of NEAT1 and downregulation of miR-125b-5p, along with SLC1A5 upregulation in tumors. Analysis of transcriptomic data revealed that tumors harboring higher SLC1A5 expression had significantly lower immune scores in CD8+, monocytes, and dendritic cells, and higher scores in M0 and M1 macrophages. Disruptions in immune modulation, metabolism, and oxidative stress components were associated with SLC1A5 aberrations in HNSCC. This study concludes that the NEAT1/miR-125b-5p/SLC1A5 cascade modulates diverse activities in oncogenicity, treatment efficacy, and immune cell profiles in head and neck/oral carcinoma.

2.
Sensors (Basel) ; 24(17)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39275446

RESUMO

Particle plasmon resonance (PPR), or localized surface plasmon resonance (LSPR), utilizes intrinsic resonance in metal nanoparticles for sensor fabrication. While diffraction grating waveguides monitor bioaffinity adsorption with out-of-plane illumination, integrating them with PPR for biomolecular detection schemes remains underexplored. This study introduces a label-free biosensing platform integrating PPR with a diffraction grating waveguide. Gold nanoparticles are immobilized on a glass slide in contact with a sample, while a UV-assisted embossed diffraction grating is positioned opposite. The setup utilizes diffraction in reflection to detect changes in the environment's refractive index, indicating biomolecular binding at the gold nanoparticle surface. The positional shift of the diffracted beam, measured with varying refractive indices of sucrose solutions, shows a sensitivity of 0.97 mm/RIU at 8 cm from a position-sensitive detector, highlighting enhanced sensitivity due to PPR-diffraction coupling near the gold nanoparticle surface. Furthermore, the sensor achieved a resolution of 3.1 × 10-4 refractive index unit and a detection limit of 4.4 pM for detection of anti-DNP. The sensitivity of the diffracted spot was confirmed using finite element method (FEM) simulations in COMSOL Multiphysics. This study presents a significant advancement in biosensing technology, offering practical solutions for sensitive, rapid, and label-free biomolecule detection.


Assuntos
Técnicas Biossensoriais , Ouro , Nanopartículas Metálicas , Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Refratometria , Análise de Elementos Finitos , Limite de Detecção
3.
J Formos Med Assoc ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39261118

RESUMO

BACKGROUND/AIMS: The study is to analyze the clinical characteristics and identify prognostic factors as well as evaluate predictive models in patients with acute-on-chronic liver failure (ACLF) from Southern Taiwan. METHODS: The cohort study was conducted using the Chang Gung Research Database. We included patients with ACLF based on the definition provided by the Asian-Pacific Association for the Study of the Liver ACLF Research Consortium (AARC). RESULTS: A total of 231 patients diagnosed with ACLF were included in this study, out of which 26 patients underwent liver transplantation (LT). The primary cause of ACLF was acute exacerbation of hepatitis B virus (HBV) in 68.4% of cases and followed by severe alcoholic hepatitis (20.8%). Among LT-free patients, the 28-day mortality rate was observed to be 31%. Older age, higher INR and ammonia levels, and the presence of severe hepatic encephalopathy on 3-6 days of treatment were independent predictors of 28-day mortality. The CLIF-C ACLF and COSSH-ACLF scores, evaluated on 3-6 days, demonstrated the highest predictive performance for 28-day mortality. The optimal cut-off values for the CLIF-C ACLF and COSSH-ACLF scores were determined to be 47 and 6.3, respectively. Patients with CLIF-C ACLF score >63 or COSSH-ACLF score >8.1 experienced 100% mortality by day 28. CONCLUSIONS: The CLIF-C ACLF and COSSH-ACLF scores, evaluated within one week after treatment, exhibit strong predictive capabilities for short-term mortality in ACLF patients. These models are valuable tools for guiding timely decision-making, including the consideration of liver transplantation or withdrawal from treatment.

4.
Entropy (Basel) ; 26(8)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39202179

RESUMO

We apply a real-space block renormalization group approach to study the critical properties of the random transverse-field Ising spin chain with multispin interactions. First, we recover the known properties of the traditional model with two-spin interactions by applying the renormalization approach for the arbitrary size of the block. For the model with three-spin couplings, we calculate the critical point and demonstrate that the phase transition is controlled by an infinite disorder fixed point. We have determined the typical correlation-length critical exponent, which seems to be different from that of the random transverse Ising chain with nearest-neighbor couplings. Thus, this model represents a new infinite disorder universality class.

5.
mBio ; 15(9): e0085224, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39162563

RESUMO

Pseudomonas aeruginosa is an opportunistic pathogen that thrives in environments associated with human activity, including soil and water altered by agriculture or pollution. Because L-lactate is a significant product of plant and animal metabolism, it can serve as a carbon source for P. aeruginosa in the diverse settings that it inhabits. In this study, we evaluate the production and use of two redundant P. aeruginosa L-lactate dehydrogenases, termed LldD and LldA. We confirm that the protein LldR represses lldD and identify a new transcription factor, called LldS, that activates lldA; these distinct regulators and the genomic contexts of lldD and lldA contribute to their differential expression. We demonstrate that the lldD and lldA genes are conditionally controlled in response to lactate isomers as well as to glycolate and ɑ-hydroxybutyrate, which, like lactate, are ɑ-hydroxycarboxylates. We also show that lldA is induced when iron availability is low. Our examination of lldD and lldA expression across depth in biofilms indicates a complex pattern that is consistent with the effects of glycolate production, iron availability, and cross-regulation on enzyme preference. Finally, macrophage infection assays reveal that both lldD and lldA contribute to persistence within host cells, underscoring the potential role of L-lactate as a carbon source during P. aeruginosa-eukaryote interactions. Together, these findings help us understand the metabolism of a key resource that may promote P. aeruginosa's success as a resident of contaminated environments and animal hosts.IMPORTANCEPseudomonas aeruginosa is a major cause of lung infections in people with cystic fibrosis, of hospital-acquired infections, and of wound infections. It consumes L-lactate, which is found at substantial levels in human blood and tissues. In this study, we investigated the spatial regulation of two redundant enzymes, called LldD and LldA, which enable L-lactate metabolism in P. aeruginosa biofilms. We uncovered mechanisms and identified compounds that control the preference of P. aeruginosa for LldD versus LldA. We also showed that both enzymes contribute to its ability to survive within macrophages, a behavior that is thought to augment the chronicity and recalcitrance of infections. Our findings shed light on a key metabolic strategy used by P. aeruginosa and have the potential to inform the development of therapies targeting bacterial metabolism during infection.


Assuntos
Regulação Bacteriana da Expressão Gênica , Macrófagos , Infecções por Pseudomonas , Pseudomonas aeruginosa , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/enzimologia , Macrófagos/microbiologia , Infecções por Pseudomonas/microbiologia , Animais , Humanos , Camundongos , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Ácido Láctico/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Viabilidade Microbiana
6.
Microorganisms ; 12(7)2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39065190

RESUMO

Ventilator-associated pneumonia (VAP) is a critical hospital-acquired infection following non-cardiac surgeries, leading to poor outcomes. This study identifies VAP risk factors in non-cardiac surgical patients and determines the causative pathogens. A retrospective analysis with 1:4 propensity-score matching was conducted on patients in a surgical intensive care unit (ICU) from 2010 to 2020 at a private tertiary medical center. Among 99 VAP patients, the mortality rate was 64.7%. VAP risk factors included prolonged mechanical ventilation (odds ratio [OR] 6.435; p < 0.001), repeat intubation (OR 6.438; p < 0.001), lower oxygenation levels upon ICU admission (OR 0.950; p < 0.001), and undergoing gastrointestinal surgery (OR 2.257; p = 0.021). The 30-day mortality risk factors in the VAP group were late-onset VAP (OR 3.450; p = 0.022), inappropriate antibiotic treatment (OR 4.083; p = 0.041), and undergoing gastrointestinal surgeries (OR 4.776; p = 0.019). Nearly half of the Gram-negative infections were resistant strains, and a third were polymicrobial infections. Non-cardiac surgical patients with VAP face adverse hospital outcomes. Identifying high-risk patients and understanding VAP's resistant and microbial nature are crucial for appropriate treatment and improved health outcomes.

7.
J Microbiol Immunol Infect ; 57(5): 771-781, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38944568

RESUMO

BACKGROUND: Liver transplantation (LT) is a pivotal treatment for end-stage liver disease. However, bloodstream infections (BSI) in the post-operative period present a significant threat to patient survival. This study aims to identify risk factors for post-LT BSI and crucial prognostic indicators for mortality among affected patients. METHODS: We conducted a retrospective study of adults diagnosed with end-stage liver disease who underwent their initial LT between 2010 and 2021. Those who developed BSI post-LT during the same hospital admission were classified into the BSI group. RESULTS: In this cohort of 1049 patients, 89 (8.4%) developed BSI post-LT, while 960 (91.5%) did not contract any infection. Among the BSI cases, 17 (19.1%) patients died. The average time to BSI onset was 48 days, with 46% occurring within the first month post-LT. Of the 123 isolated microorganisms, 97 (78.8%) were gram-negative bacteria. BSI patients had significantly longer stays in the intensive care unit and hospital compared to non-infected patients. The 90-day and in-hospital mortality rates for recipients with BSI were significantly higher than those without infections. Multivariate analysis indicated heightened BSI risk in patients with blood loss >3000 mL during LT (odds ratio [OR] 2.128), re-operation within 30 days (OR 2.341), post-LT bile leakage (OR 3.536), and graft rejection (OR 2.194). Additionally, chronic kidney disease (OR 6.288), each 1000 mL increase in intraoperative blood loss (OR 1.147) significantly raised mortality risk in BSI patients, whereas each 0.1 mg/dL increase in albumin levels correlated with a lower risk of death from BSI (OR 0.810). CONCLUSIONS: This study underscores the need for careful monitoring and management in the post-LT period, especially for patients at higher risk of BSI. It also suggests that serum albumin levels could serve as a valuable prognostic indicator for outcomes in LT recipients experiencing BSI.


Assuntos
Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Fatores de Risco , Prognóstico , Adulto , Bacteriemia/mortalidade , Bacteriemia/microbiologia , Mortalidade Hospitalar , Transplantados/estatística & dados numéricos , Idoso , Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/cirurgia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/epidemiologia
8.
Front Med (Lausanne) ; 11: 1378207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707192

RESUMO

Objective: To outline the epidemiology of puerperal mastitis caused by methicillin-resistant Staphylococcus aureus (MRSA) and evaluate the effect of an infection control bundle on its incidence. Methods: A surge in MRSA puerperal mastitis was noted in a community hospital in September 2009. MRSA samples from mastitis cases and the environment underwent typing using multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec), gene encoding surface protein A (spa), accessory gene regulator (agr), and pulsed-field gel electrophoresis (PFGE). The phenotypic characteristics, including superantigen toxin profiles, gene encoding Panton-Valentine leucocidin (pvl), and minimal inhibitory concentration (MIC) against vancomycin, were ascertained. Subsequently, an infection control bundle emphasizing contact precautions was introduced, and mastitis incidence rates pre- and post-intervention were compared. Results: The majority of cases occurred within 6 weeks post-delivery in first-time mothers. Of the 42 S. aureus isolates (27 from mastitis and 15 from colonized staff and environmental sources), 25 (92.6%) clinical and 3 (20%) colonized MRSA were identified as ST59-SCCmecVT-spa t437-agr group I with a vancomycin MIC of 1 mg/L, pvl-positive, and predominantly with a consistent toxin profile (seb-selk-selr). PFGE revealed 13 patterns; pulsotype B exhibited clonal relatedness between two clinical and three colonized MRSA samples. Post-intervention, the incidence of both mastitis and MRSA mastitis notably decreased from 13.01 to 1.78 and from 3.70 to 0.99 episodes per 100 deliveries, respectively. Conclusion: Distinct community-associated MRSA (CA-MRSA) clones were detected among puerperal mastitis patients and colonized staff. The outbreak was effectively controlled following the implementation of a targeted infection control bundle.

9.
Front Oncol ; 14: 1297153, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720805

RESUMO

Purpose: This study aims to evaluate the efficacy and safety of ultrasound-guided percutaneous biopsy of the first hepatic hilum lesion, and examine its clinical value of diagnosis and treatment. Methods: We conducted a retrospective study on patients diagnosed with the first hepatic hilum lesions at Fujian Provincial Hospital between February 2015 and October 2022. We selected patients who had lesions in the first hepatic hilum(including a 2cm surrounding area of the left/right hepatic ducts and upper-middle segment of the common bile duct) and the liver periphery(in the peripheral area of the liver, outside of the above-mentioned first hepatic porta region). These patients underwent percutaneous ultrasound-guided core needle biopsy (PUS-CNB) with cognitive fusion guidance using CT, MRI, or PET-CT. We compared the safety and efficacy of PUS-CNB in the first hepatic hilum and the liver periphery to explore the value of PUS-CNB in optimizing the clinical treatment of the first hepatic hilum lesions. Results: The studied includes 38 cases of the first hepatic hilum cases (18 females; 20 males), 23 presented with mass-forming tumors while the remaining 15 exhibited diffuse infiltrative tumors, with an average diameter of 4.65± 2.51 cm. The percutaneous biopsy procedure, conducted under ultrasound guidance, had an average operation time of 14.55 ± 2.73 minutes, and resulted in a postoperative bleeding volume of approximately 10.79 ± 2.79 ml. The diagnostic success rate was noted to be as high as 92.11% among the participants who underwent percutaneous biopsy of the first hepatic hilum. Procedural complications, such as bleeding, bile leakage, intestinal perforation, infection or needle tract seeding, did not occur during or after the biopsy procedure. Affected by biopsy results, 5 altered their clinical treatment plans accordingly, 24patients received non-surgical treatment, 9 underwent surgical treatment, 5 underwent radiofrequency ablation for the lesions. The study comprised a total of 112 cases for percutaneous biopsy of the liver periphery. The safety and effectiveness of the two biopsy techniques were comparable, with diagnostic success rates of 92.11% VS. 94.34%, respectively (p = 0.61). Conclusion: Cognitive fusion of ultrasound and multi-modal imaging for the first hepatic hilum lesion puncture biopsy is a safe and effective diagnostic procedure, with better diagnostic rate, may improve clinical value of diagnosis and treatment of various diseases.

10.
bioRxiv ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38562866

RESUMO

Pseudomonas aeruginosa is an opportunistic pathogen that thrives in environments associated with human activity, including soil and water altered by agriculture or pollution. Because L-lactate is a significant product of plant and animal metabolism, it is available to serve as a carbon source for P. aeruginosa in the diverse settings it inhabits. Here, we evaluate P. aeruginosa's production and use of its redundant L-lactate dehydrogenases, termed LldD and LldA. We confirm that the protein LldR represses lldD and identify a new transcription factor, called LldS, that activates lldA; these distinct regulators and the genomic contexts of lldD and lldA contribute to their differential expression. We demonstrate that the lldD and lldA genes are conditionally controlled in response to lactate isomers as well as to glycolate and - hydroxybutyrate, which, like lactate, are -hydroxycarboxylates. We also show that lldA is induced when iron availability is low. Our examination of lldD and lldA expression across depth in biofilms indicates a complex pattern that is consistent with the effects of glycolate production, iron availability, and cross-regulation on enzyme preference. Finally, macrophage infection assays revealed that both lldD and lldA contribute to persistence within host cells, underscoring the potential role of L-lactate as a carbon source during P. aeruginosa-eukaryote interactions. Together, these findings help us understand the metabolism of a key resource that may promote P. aeruginosa's success as a resident of contaminated environments and animal hosts.

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