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1.
Diagnostics (Basel) ; 14(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38337780

RESUMEN

High-resolution manometry (HRM) facilitates the detailed evaluation of esophageal motility. In December 2020, Chicago classification (CC) version 4.0 introduced modifications to improve consistency and accuracy. We conducted this study to compare the differences in the interpretations of HRM examinations between CC 3.0 and 4.0. Consecutive HRM records at a Taiwan tertiary medical center, including wet swallows and MRS performed in both supine and sitting positions from October 2019 to May 2021, were retrospectively reviewed and analyzed using both CC versions 3.0 and 4.0. A total of 105 patients were enrolled, and 102 patients completed the exam, while three could not tolerate HRM sitting up. Refractory gastroesophageal reflux disease (GERD) symptoms (n = 65, 63.7%) and dysphagia (n = 37, 36.3%) were the main indications. A total of 18 patients (17.6%) were reclassified to new diagnoses using CC 4.0. Of the 11 patients initially diagnosed with absent contractility, 3 (27.3%) were reclassified as having Type 1 achalasia. Of the 18 patients initially diagnosed with IEM, 6 (33.3%) were reclassified as normal. The incidence of diagnosis changes was similar in both the dysphagia and refractory GERD symptoms groups (21.6% versus 15.3%, p = 0.43). The use of CC 4.0 led to changes in the diagnoses of esophageal motility disease, irrespective of examination indications. Early adoption improves the accuracy of diagnoses and affects patient management.

2.
World J Clin Cases ; 11(25): 5863-5869, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37727488

RESUMEN

BACKGROUND: Closed reduction and internal fixation with intramedullary nails has been widely accepted for treating intertrochanteric fractures. AIM: To focus on how to avoid displacement of the lesser trochanter in unstable intertrochanteric fractures. METHODS: We developed a lesser trochanteric reduction fixator for treating intertrochanteric fractures through fixing the lesser trochanter by combining the loop plate through the fixator after reduction by the reducer. Five patients with intertrochanteric fractures treated with the newly developed lesser trochanteric reduction fixator and loop plate combined with intramedullary nails, and 20 patients with intertrochanteric fractures treated with simple intramedullary nails were selected from December 2020 to March 2021. RESULTS: The postoperative Harris hip score was significantly higher in patients treated with the lesser trochanteric reduction fixator than in patients treated without the lesser trochanteric reduction fixator, which indicated that this lesser trochanteric reduction fixator had a positive impact on rehabilitation of the hip joint after surgery and could significantly improve the quality of life of patients. CONCLUSION: We fully realize the significance of trochanteric reduction and fixation, namely, reconstruction of structures under pressure, in the treatment of intertrochanteric fractures. As long as the general condition of patients is favorable and they are willing to undergo surgery, fixation of the main fracture end should be performed and the lesser trochanter should be reduced and fixed at the same time.

3.
Eye Contact Lens ; 49(8): 348-356, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37378653

RESUMEN

OBJECTIVES: The long-term use of contact lenses may damage the structure of the ocular surface and cause metabolic disorders in corneal cells. Vitamins and amino acids help maintain the physiological function of the eye. In the present study, the effects of nutrient (vitamin and amino acid) supplementation on corneal cell repair after contact lens-induced damage was investigated. METHODS: High-performance liquid chromatography was used to quantify the nutrient contents of minimum essential medium, and the MTT assay was used to measure the viability of corneal cells. A Statens Seruminstitut rabbit cornea cellular model was established to simulate contact lens-induced keratopathy and investigate the effects of vitamin and amino acid supplementations on corneal cell repair. RESULTS: The high water content lens group (78%) has a cell viability as high as 83.3%, whereas the cell viability of the low water content lens group (38%) is only 51.6%. The 32.0% difference between the two groups confirms the correlation between water content of lens and corneal viability. CONCLUSIONS: Vitamin B2, vitamin B12, asparagine, and taurine supplementation may help improve contact lens-induced damage.


Asunto(s)
Lentes de Contacto , Lesiones de la Cornea , Animales , Conejos , Córnea/metabolismo , Lentes de Contacto/efectos adversos , Vitaminas/farmacología , Vitaminas/metabolismo , Suplementos Dietéticos , Nutrientes , Aminoácidos/metabolismo , Agua
4.
Microbiol Spectr ; 11(4): e0053023, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37358428

RESUMEN

With the increasing and inappropriate use of colistin, the emerging colistin-resistant isolates have been frequently reported during the last few decades. Therefore, new potential targets and adjuvants to reverse colistin resistance are urgently needed. Our previous study has confirmed a marked increase of colistin susceptibility (16-fold compared to the wild-type Salmonella strain) of cpxR overexpression strain JSΔacrBΔcpxR::kan/pcpxR (simplified as JSΔΔ/pR). To searching for potential new drug targets, the transcriptome and metabolome analysis were carried out in this study. We found that the more susceptible strain JSΔΔ/pR displayed striking perturbations at both the transcriptomics and metabolomics levels. The virulence-related genes and colistin resistance-related genes (CRRGs) were significantly downregulated in JSΔΔ/pR. There were significant accumulation of citrate, α-ketoglutaric acid, and agmatine sulfate in JSΔΔ/pR, and exogenous supplement of them could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. Additionally, we also demonstrated that AcrB and CpxR could target the ATP and reactive oxygen species (ROS) generation, but not proton motive force (PMF) production pathway to potentiate antibacterial activity of colistin. Collectively, these findings have revealed several previously unknown mechanisms contributing to increased colistin susceptibility and identified potential targets and adjuvants for potentiating colistin treatment of Salmonella infections. IMPORTANCE Emergence of multidrug-resistant (MDR) Gram-negative (G-) bacteria have led to the reconsideration of colistin as the last-resort therapeutic option for health care-associated infections. Finding new drug targets and strategies against the spread of MDR G- bacteria are global challenges for the life sciences community and public health. In this paper, we demonstrated the more susceptibility strain JSΔΔ/pR displayed striking perturbations at both the transcriptomics and metabolomics levels and revealed several previously unknown regulatory mechanisms of AcrB and CpxR on the colistin susceptibility. Importantly, we found that exogenous supplement of citrate, α-ketoglutaric acid, and agmatine sulfate could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. These results provide a theoretical basis for finding potential new drug targets and adjuvants.


Asunto(s)
Agmatina , Colistina , Colistina/farmacología , Salmonella typhimurium/genética , Transcriptoma , Agmatina/farmacología , Ácidos Cetoglutáricos/farmacología , Antibacterianos/farmacología , Metaboloma , Pruebas de Sensibilidad Microbiana
5.
World J Clin Cases ; 10(35): 12804-12811, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36569017

RESUMEN

Esophageal squamous cell carcinoma is one of the most common malignant tumors in the digestive system in China and the world. Most patients are diagnosed as locally advanced or advanced stage. Concurrent chemoradiotherapy is the standard treatment for locally advanced esophageal squamous cell carcinoma. This study intends to summarize the evidence-based medical evidence of the treatment principle of locally advanced esophageal squamous cell carcinoma, the selection of radiotherapy dose, the outline of radiotherapy target and the selection of chemotherapy scheme. As a result, the effect of radiotherapy and chemotherapy is equivalent to that of surgery for the radical treatment of esophageal squamous cell carcinoma. In the era of immunization, it is recommended to use involved field irradiation. Fluorouracil plus cisplatin regimen is the standard chemotherapy regimen. FOLFOX regimen and paclitaxel plus fluorouracil regimen are optional concurrent chemotherapy regimens. The toxic and side effects of different chemotherapy regimens are different, which can be selected according to the actual situation of patients.

6.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36232387

RESUMEN

Onion (Allium cepa L.), rich in flavonoids (particularly quercetin), reportedly has anti-obesity properties, but the underlying mechanisms and associated health issues remain unclear. In this study, we compared the effects of dried onion powder (DO) with that of quercetin on high-fat diet (HFD)-induced obesity, nonalcoholic fatty liver disease, and retinal neovascularization. Briefly, rats (n = 9-10 per group) were divided into control, HFD alone (43% fat), HFD + DO (1% DO), HFD + 5DO (5% DO, w/w), and HFD + quercetin (180 mg/kg). After 12 weeks, body fat, markers of metabolism, fatty liver, steatohepatitis, and retinopathy were analyzed. The results revealed that DO and 5DO dose-dependently suppressed body weight, visceral and subcutaneous fat accumulation, and epididymal adipocyte in HFD-fed rats. DO also decreased HFD-induced ALT, AST, free fatty acid, glucose, proinflammatory cytokines, and oxidative stress. DO and 5DO groups had lower triglycerides, total cholesterol, proinflammatory cytokine levels, and ACC-α (a fatty acid synthesis-associated enzyme) expression but higher hepatic antioxidant enzyme activities and fecal lipids. 5DO exhibited better or similar efficacy to quercetin. Both 5DO and quercetin increased fecal levels of acetic acid and butyric acid similarly. They also reduced lipid peroxidation of the eye, retinal adiposity, and neovascularization. However, quercetin resulted in a more apparent decrease in regulation of the Raf/MAPK pathway than DO in eye specimens. Conclusively, DO suppresses visceral, subcutaneous, and liver fat accumulation better than quercetin likely due to higher fecal fat excretion and lower oxidative stress, proinflammatory cytokine levels, and ACC-α expression. Quercetin regulating signal pathways is better than DO at reducing retinal adiposity and neovascularization.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Enfermedades de la Retina , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Ácido Butírico/farmacología , Colesterol/metabolismo , Citocinas/metabolismo , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos no Esterificados/metabolismo , Glucosa/metabolismo , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/etiología , Obesidad/metabolismo , Cebollas , Polvos/farmacología , Quercetina/metabolismo , Quercetina/farmacología , Quercetina/uso terapéutico , Ratas , Enfermedades de la Retina/metabolismo , Triglicéridos/metabolismo
7.
Front Aging Neurosci ; 14: 885393, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966787

RESUMEN

Depression is associated with gut dysbiosis that disrupts a gut-brain bidirectional axis. Gray matter volume changes in cortical and subcortical structures, including prefrontal regions and the hippocampus, have also been noted in depressive disorders. However, the link between gut microbiota and brain structures in depressed patients remains elusive. Neuropsychiatric measures, stool samples, and structural brain images were collected from 36 patients with late-life depression (LLD) and 17 healthy controls. 16S ribosomal RNA (rRNA) gene sequencing was used to profile stool microbial communities for quantitation of microbial composition, abundance, and diversity. T1-weighted brain images were assessed with voxel-based morphometry to detect alterations in gray matter volume between groups. Correlation analysis was performed to identify the possible association between depressive symptoms, brain structures and gut microbiota. We found a significant difference in the gut microbial composition between patients with late-life depression (LLD) and healthy controls. The genera Enterobacter and Burkholderia were positively correlated with depressive symptoms and negatively correlated with brain structural signatures in regions associated with memory, somatosensory integration, and emotional processing/cognition/regulation. Our study purports the microbiota-gut-brain axis as a potential mechanism mediating the symptomatology of LLD patients, which may facilitate the development of therapeutic strategies targeting gut microbes in the treatment of elderly depressed patients.

8.
Microbiol Spectr ; 10(3): e0026522, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35510850

RESUMEN

Antimicrobial resistance in Morganella morganii is increasing in recent years, which is mainly introduced via extra genetic and mobile elements. The aim of our study is to analyze the multidrug resistance (MDR) and characterize the mobile genetic elements (MGEs) in M. morganii isolates. Here, we report the characteristic of a pathogenic M. morganii isolate containing multidrug resistance genes that are mainly carried by a novel transposon Tn7376 and a genomic island. Sequence analysis suggested that the Tn7376 could be generated through homologous recombination between two different IS26-bounded translocatable units (TUs), namely, module A (IS26-Hp-IS26-mph(A)-mrx(A)-mphR-IS6100-chrA-sul1-qacEΔ1) and module B (ISCR1-sul1-qacEΔ1-cmlA1-aadA1-aadB-intI1-IS26), and the genomic island named MMGI-4 might derive from a partial structure of different original genomic islands that also carried IS26-mediated TUs. Notably, a 2,518-bp sequence linked to the module A and B contains a 570-bp dfrA24 gene. To the best of our knowledge, this is the first report of the novel Tn7376 possessing a complex class 1 integron that carried an infrequent gene dfrA24 in M. morganii. IMPORTANCE Mobile genetic elements (MGEs), especially for IS26-bounded translocatable units, may act as a reservoir for a variety of antimicrobial resistance genes in clinically important pathogenic bacteria. We expounded this significant genetic characteristic by investigating a representative M. morganii isolate containing multidrug resistance genes, including the infrequent dfrA24. Our study suggested that these acquired resistance genes were mainly driven by IS26-flanked important MGEs, such as the novel Tn7376 and the MMGI-4. We demonstrated that IS26-related MGEs contributed to the emergence of the extra gene dfrA24 in M. morganii through some potential genetic events like recombination, transposition, and integration. Therefore, it is of importance to investigate persistently the prevalence these MEGs in the clinical pathogens to provide risk assessment of emergence and development of novel resistance genes.


Asunto(s)
Elementos Transponibles de ADN , Farmacorresistencia Bacteriana Múltiple , Islas Genómicas , Morganella morganii , Antibacterianos , Farmacorresistencia Bacteriana Múltiple/genética , Genes MDR , Integrones/genética , Morganella morganii/genética
9.
Chem Sci ; 12(8): 2925-2930, 2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34164059

RESUMEN

Nonribosomal peptide synthetases (NRPSs) are modular enzymes that use a thiotemplate mechanism to assemble the peptide backbones of structurally diverse and biologically active natural products in bacteria and fungi. Unlike these canonical multi-modular NRPSs, single-module NRPS-like enzymes, which lack the key condensation (C) domain, are rare in bacteria, and have been largely unexplored to date. Here, we report the discovery of a gene cluster (gup) encoding a NRPS-like megasynthetase through genome mining. Heterologous expression of the gup cluster led to the production of two unprecedented alkaloids, guanipiperazines A and B. The NRPS-like enzyme activates two l-tyrosine molecules, reduces them to the corresponding amino aldehydes, and forms an unstable imine product. The subsequent enzymatic reduction affords piperazine, which can be morphed by a P450 monooxygenase into a highly strained compound through C-O bond formation. Further intermolecular oxidative coupling forming the C-C or C-O bond is catalyzed by another P450 enzyme. This work reveals the huge potential of NRPS-like biosynthetic gene clusters in the discovery of novel natural products.

10.
Helicobacter ; 26(4): e12824, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34117671

RESUMEN

BACKGROUND: Depressive disorder is a major psychiatric illness, and a disturbed brain-gut-microbiome axis may contribute to its pathophysiology. Chronic Helicobacter pylori (H. pylori) infections are common in the general population and using multiple antibiotics is required for its eradication, which is associated with gut dysbiosis and may lead to depression. We aimed to evaluate the risk of psychiatrist-diagnosed depression in patients with peptic ulcer diseases (PUD) receiving anti-H. pylori therapy. MATERIALS AND METHODS: We collected data from the National Health Insurance Research Database (NHIRD) in Taiwan on PUD patients undergoing antibiotic treatment for H. pylori infection; patients and controls were matched for age, sex, income, level of urbanization, and comorbidities. RESULTS: Of the 1 million beneficiaries in the NHIRD, we identified 7087 patients for inclusion in the eradication cohort and 7087 matched non-eradication controls with PUD. Antibiotic therapy is associated with a short-term (<30 days) increase in the incidence of psychiatrist-diagnosed depressive disorder (p = 0.009, after multiple comparisons with Bonferroni correction) in the eradication cohort compared with the controls. Female (OR: 4.55, 95% CI: 1.53-13.48) PUD patients were more likely to display an increased risk of depression within 30 days after eradication therapy. Clarithromycin use was related to an elevated likelihood (OR: 3.14, 95% CI: 1.45-6.80) of subsequent depressive disorder within 30 days after eradication therapy. CONCLUSIONS: Antibiotic eradication treatment for H. pylori infection is associated with a significant short-term (less than 30 days) increase in the incidence of psychiatrist-diagnosed depressive disorder, which can be overlooked by gastroenterologists and general practitioners.


Asunto(s)
Trastorno Depresivo , Infecciones por Helicobacter , Helicobacter pylori , Antibacterianos/uso terapéutico , Antiulcerosos/uso terapéutico , Estudios de Cohortes , Trastorno Depresivo/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/epidemiología , Humanos , Masculino , Taiwán/epidemiología
11.
Molecules ; 26(9)2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33923222

RESUMEN

Hyaluronic acid (HA) is a glycosaminoglycan that was first isolated and identified from the vitreous body of a bull's eye. HA is ubiquitous in the soft connective tissues of animals and therefore has high tissue compatibility for use in medication. Because of HA's biological safety and water retention properties, it has many ophthalmology-related applications, such as in intravitreal injection, dry eye treatment, and contact lenses. Due to its broad range of applications, the identification and quantification of HA is a critical topic. This review article discusses current methods for analyzing HA. Contact lenses have become a widely used medical device, with HA commonly used as an additive to their production material, surface coating, and multipurpose solution. HA molecules on contact lenses retain moisture and increase the wearer's comfort. HA absorbed by contact lenses can also gradually release to the anterior segment of the eyes to treat dry eye. This review discusses applications of HA in ophthalmology.


Asunto(s)
Sistemas de Liberación de Medicamentos , Síndromes de Ojo Seco/tratamiento farmacológico , Ácido Hialurónico/uso terapéutico , Oftalmología , Lentes de Contacto/efectos adversos , Síndromes de Ojo Seco/patología , Humanos
12.
J BUON ; 25(2): 1028-1034, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32521902

RESUMEN

PURPOSE: Osteosarcoma causes extensive human mortality and there is urgent need to develop novel therapies or to identify efficient therapeutic targets for its management. Herein the role and therapeutic potential of miR-17 was explored in osteosarcoma. METHODS: The normal hFOB.19 cell line and the osteosarcoma cell lines SAOS-2, HOS, 143B, T1-73 and mG63 were used in the present study. The expression analysis of miR-17 was carried out by quantitative Real-Time polymerase chain reaction (qRT-PCR). Lipofectamine 2000 reagent (Invitrogen, Carlsbad, CA, USA) was used for transfection. WST-1 assay was used for determination of cell proliferation and autophagy was detected by transmission electron microscopy (TEM). Wound healing and transwell assays were used for the determination of cell migration and invasion. Protein expression was determined by western blot analysis. RESULTS: The expression of miR-17 was significantly elevated in all the osteosarcoma cells. Suppression of miR-17 resulted in decrease of the viability and colony formation of the SAOS-2 osteosarcoma cells. The inhibition of SAOS-2 cell proliferation upon miR-17 suppression was found to be due to induction of autophagy which was accompanied with enhancement in the expression of LC3B II and Beclin-1. Suppression of miR-17 was also accompanied by inhibition of the SAOS-2 cell migration and invasion. The in silico analysis showed that miR-187 targets PTEN in the SAOS-2 cells. The expression of PTEN was found to be downregulated in all the osteosarcoma cells and suppression of miR-17 expression caused enhancement in the expression of PTEN. Overexpression of miR-17 caused inhibition of the proliferation and colony formation of the SAOS-2 cells. Additionally, silencing of miR-17 could abolish the effects of miR-17 inhibition in the SAOS-2 cells. CONCLUSION: MiR-17 may be proven a therapeutic target in the management of osteosarcoma.


Asunto(s)
Neoplasias Óseas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Osteosarcoma/metabolismo , Fosfohidrolasa PTEN/biosíntesis , Autofagia/fisiología , Neoplasias Óseas/enzimología , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Humanos , Invasividad Neoplásica , Osteosarcoma/enzimología , Osteosarcoma/genética , Osteosarcoma/patología , Fosfohidrolasa PTEN/genética , Transfección , Regulación hacia Arriba
13.
Probiotics Antimicrob Proteins ; 12(3): 980-993, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31691208

RESUMEN

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by abdominal pain and alterations in bowel habits. Current treatments for IBS are unsatisfactory due to its multifactorial pathogenesis involving the microbiota-gut-brain axis. Lactobacillus plantarum PS128 (PS128) was reported to exhibit neuromodulatory activity which may be beneficial for improving IBS. This study aimed to investigate the effect of PS128 on visceral hypersensitivity (VH) and the gut-brain axis using a 5-hydroxytryptophan (5-HTP)-induced VH rat model without colonic inflammation induction, mimicking the characteristics of IBS. Male Sprague-Dawley rats were administered with PS128 (109 CFU in 0.2 mL saline/rat/day) or saline (0.2 mL saline/rat/day) for 14 days. Colorectal distension (CRD) with simultaneous electromyography recording was performed 30 min before and 30 min after the 5-HTP injection. Levels of neuropeptides and neurotrophins were analyzed. PS128 significantly reduced VH induced by the 5-HTP injection and CRD. Neurotransmitter protein levels, substance P, CGRP, BDNF, and NGF, were decreased in the dorsal root ganglion but increased in the spinal cord in response to the 5-HTP injection; PS128 reversed these changes. The hypothalamic-pituitary-adrenal axis was modulated by PS128 with decreased corticosterone concentration in serum and the expression of mineralocorticoid receptors in the amygdala. Oral administration of PS128 inhibited 5-HTP-induced VH during CRD. The ameliorative effect on VH suggests the potential application of PS128 for IBS.


Asunto(s)
Sistema Hipotálamo-Hipofisario , Síndrome del Colon Irritable/terapia , Lactobacillus plantarum , Sistema Hipófiso-Suprarrenal , Probióticos/administración & dosificación , Animales , Sistema Nervioso Central/metabolismo , Masculino , Neuropéptidos/metabolismo , Ratas , Ratas Sprague-Dawley
14.
Inorg Chem ; 58(21): 14617-14625, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31626549

RESUMEN

Titanium-oxo clusters (TOCs) are attractive as a rapidly growing class of molecular materials due to their use as molecular models and precursors of nano-titanium-oxide. However, most TOCs can only be dissolved in nonaqueous solvents, which largely limits their potential applications in biological or environmental situations. Very few water-soluble TOCs were reported, which can be used directly in aqueous biomedical systems. However, until now, no research studies of such TOCs involved in biomedical fields have been documented. We report here a series of lanthanide-titanium-oxo clusters (LnTOCs) formulated as {H2@[Ln2Ti8(µ3-O)8(µ2-O)4(Ac)16]}3·24CH3CN·23H2O (Ln = Eu(III) 1, Tb(III) 2, and Yb(III) 3). The compounds are easily soluble in water and form a stable solution of the cluster aggregates (LnTOC-a). Therefore, nano-biocompatible TiO materals can be prepared from these LnTOCs just by dissolving them in water. The nanoscale aggregates in water solutions were characterized by SEI-MS, 1H NMR, XPS, IR, and EDS mapping. Using the EuTOC-a solution, excellent fluorescence sensor properties for biomolecule ascorbic acid were found. Furthermore, biocompatibility and fluorescent labeling properties of the EuTOC-a for HeLa cells were evaluated. The results indicated that water-soluble LnTOCs can be used to prepare biocompatible fluorescent Ln-Ti-O nanomaterials.


Asunto(s)
Materiales Biocompatibles/química , Elementos de la Serie de los Lantanoides/química , Nanoestructuras/química , Oxígeno/química , Titanio/química , Agua/química , Células HeLa , Humanos , Tamaño de la Partícula , Solubilidad
15.
Chem Commun (Camb) ; 55(82): 12360-12363, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31559989

RESUMEN

Photoactive nano TiO2 particles with fluorescent properties have attracted great attention because of their potential applications in photodynamic therapy. Herein we report first a simple method to prepare water soluble fluorescent nano titanium oxide particles from titanium-oxo-clusters (TOCs). The nano material was characterized as an aggregate of titanium-oxo-clusters, which can be used directly in aqueous systems for investigations in biomedical fields.


Asunto(s)
Materiales Biocompatibles/síntesis química , Colorantes Fluorescentes/síntesis química , Nanoestructuras/química , Titanio/química , Materiales Biocompatibles/química , Investigación Biomédica , Colorantes Fluorescentes/química , Tamaño de la Partícula , Fotoquimioterapia , Solubilidad , Propiedades de Superficie
16.
Chem Asian J ; 14(18): 3198-3204, 2019 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-31397073

RESUMEN

Dye molecules pre-anchored on titanium oxo clusters (dye-TOCs) are attractive as model compounds of dye-sensitized titanium oxide. To investigate the effects of the dye ligand structures of the dye-TOCs on photocurrent conversion, a series of dye-TOCs with the same Ti6 core structure and different antenna ligands (L) was synthesized and characterized crystallographically. The TOCs have the same structural formula of [Ti6 O4 L2 (O3 PPh)2 (OiPr)10 ]. Two types of dyes with para- or meta-substituted structures were designed and used as the ligands. The results show that charge transfer from the donor group to the TiO core of the TOCs with the para-substituted ligands is stronger than those with the meta-substituted ligands. The steric effect of the ligands also greatly influences the photocurrent density. Larger branched structures of the dye ligands reduce the coverage density of the dye-TOCs on TiO2 electrodes and also weaken the effective covalent bonding of the dye-TOCs on the electrode, and consequently, the photocurrent is decreased.

17.
Inorg Chem ; 58(14): 9246-9252, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31268320

RESUMEN

Model studies on dye sensitized titanium oxides have attracted wide interest with respect to their importance in understanding photoelectric and photophysical processes. Ligand modified titanium oxo clusters (TOCs) have been considered as the most appropriate models for dye sensitized solar cells (DSSCs) on the basis of their atomically precise structures. However, the ligands used previously in TOC models were seldom the dyes that really applied in DSSCs due to the difficulty with which the crystals of the dye anchored TOCs are obtained. We report herein a series of TOCs with the popularly used arylamine-cyanoacrylate dyes. As the closest model of DSSCs, the TOCs were studied by DFT calculations based on their accurate structural information. They have also been applied to photoelectric conversion evaluation by a solar cell device. Both the theoretical and application results showed that the synergistic effect of intradye molecular charge transfer (ICT) and dye to TiO cluster charge transfer (LMCT) is important in increasing the power conversion efficiency.

18.
Sci Rep ; 9(1): 6580, 2019 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-31036843

RESUMEN

The cognitive control network (CCN) is a network responsible for multiple executive functions, which are impaired in covert hepatic encephalopathy (CHE). We aimed to use functional connectivity (FC) magnetic resonance imaging to test the hypothesis that CHE manifested with disconnection within the CCN, which is associated with impaired neuropsychiatric and biochemical profiles. CHE was detected with abnormally low psychometric hepatic encephalopathy scores (PHES) (total cut-off score <-4). Two seeds in the dorsal anterior cingulate cortex (dACC) and the dorsolateral prefrontal cortex (DLPFC) were used to calculate the FC map within the CCN. Pearson correlation analysis was performed between the CCN and psychometric, biochemical profiles including ammonia, Interleukin (IL)-6, and tumor necrosis factor (TNF)-α. Eighteen CHE, 36 non-HE (NHE) cirrhotic patients and 36 controls were studied. Significant differences in FC were noted among groups, which revealed CHE patients had a lower FC in the bilateral lateral occipital cortex (seed in the bilateral dACC) and in the right lateral occipital and precuneus cortices (seed in the left DLPFC) (P < 0.05, corrected) compared with NHE. Progressively decreased FC in the left precentral gyrus within the CCN was noted from control, NHE to CHE. PHES positively and biochemistry negatively correlated with FC in the CCN. In conclusion, CHE patients showed aberrant FC within the CCN which is correlated with both cognitive dysfunction and biochemical profiles. Ammonia and pro-inflammatory cytokines may contribute to the occurrence of aberrant connectivity. Impaired FC within the CCN may serve as a complementary biomarker for CHE.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encefalopatía Hepática/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Psicometría , Anciano , Amoníaco/sangre , Encéfalo/fisiopatología , Mapeo Encefálico , Cognición/fisiología , Función Ejecutiva/fisiología , Femenino , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/fisiopatología , Encefalopatía Hepática/sangre , Encefalopatía Hepática/fisiopatología , Humanos , Interleucina-6/sangre , Cirrosis Hepática/sangre , Cirrosis Hepática/fisiopatología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiopatología , Factor de Necrosis Tumoral alfa/sangre
19.
Inorg Chem ; 58(4): 2736-2743, 2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30729787

RESUMEN

Titanium oxo clusters (TOCs) have become one of the worldwide hot research topics because they are excellent molecular TiO materials having unique photoactive properties and can been used as models of dye-sensitized solar cells (DSSCs). S-Heterocyclic ligands such as thiophene (Th) and tetrathiafulvalene (TTF) derivatives have been widely used in electronic or photoelectronic devices and solar cells. However, a study of the synthesis and properties of TOCs anchored with Th and TTF derivatives is missing. Herein four such TOCs as single crystals were synthesized and structurally characterized: [Ti3O(OiPr)8(LTh)2] (1), [Ti4O2(OiPr)10(LTTF)2] (2), [Ti6O4(OiPr)10(LTh)2(O3PPh)2] (3), and [Ti6O4(OiPr)10(LTTF)2(O3PPh)2] (4). Charge transfer from the Th or TTF electron donor to the TOC core was evaluated by electronic spectra and theoretical calculations. This work first systematically investigated the photoelectrochemistry of TOCs with different conjugated S-heterocyclic ligands in molecular levels. The photocurrent densities of these cluster-modified TiO2 electrodes were examined using DSSCs, which were well responsive to irradiation. The photocurrents of TTF cluster-modified electrodes are higher than those of the Th cluster-modified electrodes because of the sulfur-rich conjugated system.

20.
Chem Commun (Camb) ; 54(71): 9933-9936, 2018 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-30116810

RESUMEN

Titanium oxo clusters (TOCs) anchored with photoactive triphenylamine (TPA) dyes are reported for the first time. The TiO2 electrodes modified with the TPA dye pre-anchored TOCs showed excellent photocurrent response properties.

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