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1.
Acad Radiol ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38494348

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is an inflammatory cancer. We aimed to explore whether preoperative inflammation biomarkers compared to the gadoxetic acid disodium (Gd-EOB-DTPA) enhanced MRI can add complementary value for predicting HCC pathological grade, and to develop a dynamic nomogram to predict solitary HCC pathological grade. METHODS: 331 patients from the Institution A were divided chronologically into the training cohort (n = 231) and internal validation cohort (n = 100), and recurrence-free survival (RFS) was determined to follow up after surgery. 79 patients from the Institution B served as the external validation cohort. Overall, 410 patients were analyzed as the complete dataset cohort. Least absolute shrinkage and selection operator (LASSO) and multivariate Logistic regression were used to gradually filter features for model construction. The area under the receiver operating characteristic curve (AUC) and decision curve analysis were used to evaluate model's performance. RESULTS: Five models of the inflammation, imaging, inflammation+AFP, inflammation+imaging and nomogram were developed. Adding inflammation to imaging model can improve the AUC in training cohort (from 0.802 to 0.869), internal validation cohort (0.827 to 0.870), external validation cohort (0.740 to 0.802) and complete dataset cohort (0.739 to 0.788), and obtain more net benefit. The nomogram had excellent performance for predicting high-grade HCC in four cohorts (AUCs: 0.882 vs. 0.869 vs. 0.829 vs. 0.806) with a good calibration, and accessed at https://predict-solitaryhccgrade.shinyapps.io/DynNomapp/. Additionally, the nomogram obtained an AUC of 0.863 (95% CI 0.797-0.913) for predicting high-grade HCC in the HCC≤ 3 cm. Kaplan-Meier survival curves demonstrated that the nomogram owned excellent stratification for HCC grade (P < 0.0001). CONCLUSION: This easy-to-use dynamic online nomogram hold promise for use as a noninvasive tool in prediction HCC grade with high accuracy and robustness.

2.
J Hepatocell Carcinoma ; 11: 427-442, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440051

RESUMO

Background: Currently, it is still confused whether preoperative aminotransferase-to-platelet ratio (APRI) and gamma-glutamyl transferase-to-platelet ratio (GPR) can predict microvascular invasion (MVI) in solitary hepatocellular carcinoma (HCC). We aimed to develop and validate a machine-learning integration model for predicting MVI using APRI, GPR and gadoxetic acid disodium (Gd-EOB-DTPA) enhanced MRI. Methods: A total of 314 patients from XinQiao Hospital of Army Medical University were divided chronologically into training set (n = 220) and internal validation set (n = 94), and recurrence-free survival was determined to follow up after surgery. Seventy-three patients from Chongqing University Three Gorges Hospital and Luzhou People's Hospital served as external validation set. Overall, 387 patients with solitary HCC were analyzed as whole dataset set. Least absolute shrinkage and selection operator, tenfold cross-validation and multivariate logistic regression were used to gradually filter features. Six machine-learning models and an ensemble of the all models (ENS) were built. The area under the receiver operating characteristic curve (AUC) and decision curve analysis were used to evaluate model's performance. Results: APRI, GPR, HBPratio3 ([liver SI‒tumor SI]/liver SI), PLT, peritumoral enhancement, non-smooth margin and peritumoral hypointensity were independent risk factors for MVI. Six machine-learning models showed good performance for predicting MVI in training set (AUCs range, 0.793-0.875), internal validation set (0.715-0.832), external validation set (0.636-0.746) and whole dataset set (0.756-0.850). The ENS achieved the highest AUCs (0.879 vs 0.858 vs 0.839 vs 0.851) in four cohorts with excellent calibration and more net benefit. Subgroup analysis indicated that ENS obtained excellent AUCs (0.900 vs 0.809 vs 0.865 vs 0.908) in HCC >5cm, ≤5cm, ≤3cm and ≤2cm cohorts. Kaplan‒Meier survival curves indicated that ENS achieved excellent stratification for MVI status. Conclusion: The APRI and GPR may be new potential biomarkers for predicting MVI of HCC. The ENS achieved optimal performance for predicting MVI in different sizes HCC and may aid in the individualized selection of surgical procedures.

3.
J Environ Manage ; 354: 120353, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377756

RESUMO

Waste beverages are utilized as resources in various valuable, albeit energy-consuming, waste-to-energy processes. There is a growing need for alternative cost-effective methods to harness their potential. This study explored the feasibility of employing waste beverages as feedstock for the counterpart component of a TiO2-based composite photocatalyst. Several commonly available carbonated soft drinks from the Japanese market have been investigated to achieve this goal. The investigation revealed that a mild hydrothermal treatment condition could transform all examined beverages into carbonaceous materials suitable for fabricating a core-shell structure with TiO2, resulting in a remarkably efficient visible light active photocatalyst. Notably, a pH-adjusted photocatalyst derived from Coca Cola® exhibited superior visible light photodegradability toward dye molecules and enhanced bactericidal efficacy compared to the counterpart derived from pure sucrose. The heightened visible light photocatalytic activity can be attributed to the distinctive carboxy-rich surface functional groups, based on the findings of experimental analyses and density functional theory calculations. The bidentate-type bonding of these groups with TiO2 induces a modified interfacial bond structure that facilitates the efficient transfer of photoexcited carriers. This study presents a novel avenue for the effective utilization and recycling of waste beverages, and adds value under environmentally benign conditions.


Assuntos
Carbono , Nanoestruturas , Luz , Nanoestruturas/química , Antibacterianos , Bebidas
4.
Int Orthop ; 48(3): 683-692, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37740768

RESUMO

PURPOSE: Total knee arthroplasty is the main method for the treatment of advanced haemophilic knee arthritis. Due to the particularity of hemophilia, the blood management plan is the focus of the perioperative period for haemophilia patients. This study aimed to investigate the clinical effect and safety of intra-articular injection of tranexamic acid in patients with haemophilia. METHODS: This is a retrospective study. According to whether tranexamic acid is used or not, patients are divided into tranexamic acid group (n=30) and non-tranexamic acid group (n=29). Total blood loss, intraoperative blood loss, complete blood count, total amount of coagulation factor VIII (FVIII) usage, coagulation biomarkers, inflammatory biomarkers, knee range of motion, knee joint function, pain status, complication rate, and patient satisfaction were assessed and compared at a mean follow-up of 16 months. RESULTS: Injecting tranexamic acid into the knee joint cavity can effectively reduce the hidden blood loss and total blood loss (P<0.001), and reduce the patient's early postoperative inflammation biomarkers, pain status, and limb swelling. Therefore, the patient can obtain a better range of motion following total knee arthroplasty. In the long run, in terms of joint function and surgical satisfaction, there are no statistically significant differences. In addition, there are no statistically significant differences between the two groups of patients in terms of the total amount of FVIII usage, length of stay, and hospitalization expenses. CONCLUSION: In patients with haemophilia, intra-articular injection of tranexamic acid during total knee arthroplasty can effectively reduce postoperative blood loss, early postoperative inflammation levels, pain and limb swelling, and enable patients to receive higher-quality rehabilitation exercises to get better joint function. Previous studies on TKA in haemophilic patients have already demonstrated the efficacy of intra-articular injections of TXA in reducing postoperative blood loss. Our study confirms this efficacy.


Assuntos
Antifibrinolíticos , Artrite , Artroplastia do Joelho , Hemofilia A , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Estudos Retrospectivos , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Hemorragia Pós-Operatória/etiologia , Injeções Intra-Articulares , Inflamação/complicações , Biomarcadores , Dor
5.
Front Med (Lausanne) ; 10: 1200592, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601800

RESUMO

Objective: In order to examine the relationship between 25-hydroxyl vitamin D and knee osteoarthritis (KOA), a meta-analysis of 8 randomized controlled trials (RCTs) publications was hereby performed. Methods: For the purpose of finding pertinent research, the databases of PubMed, Embase and the Cochrane Library were searched. Factors including tibial cartilage volume, joint space width (JSW), synovial fluid volume, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were correspondingly evaluated, and the results were expressed using SMD and 95% confidence intervals (CI). Results: The present meta-analysis evaluated the effects of vitamin D supplementation in patients with knee osteoarthritis, with 3,077 patients included. The results showed that vitamin D administration had a statistically significant impact on the amount of synovial fluid, Visual Analog Scale (VAS) and tibial cartilage. The pain and function scales of the WOMAC scale presented a statistically significant difference, and there was no discernible difference between the vitamin D and placebo groups in the stiffness scale. Additionally, bone marrow lesions and alterations in the diameter of the joint space were not influenced by the administration of vitamin D, and according to a subgroup study, a daily vitamin D supplement containing more than 2,000 IU significantly slowed the development of synovial tissue. Conclusion: Vitamin D supplementation did benefit those suffering from knee discomfort and knee dysfunction. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022332033, identifier: CRD42022332033.

6.
J Colloid Interface Sci ; 608(Pt 2): 1638-1651, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34749138

RESUMO

Sacrifiers-promoted photocatalysis is a useful way to achieve high efficiency photoreduction and photocatalytic hydrogen production for photocatalysts of weak reductive power such as TiO2. Herein we report a new method to fabricate a unique dyadic hybrid consisting of closely compacted crystalline (anatase) and titanium glycerolate (TiG)-derived organic group-retained amorphous nanoparticles to validate adsorption-stored sacrifiers-promoted photocatalysis instead of using sacrifiers in bulk solution. It was found that ascorbic acid (AA)-modified TiG prepared at a small fraction of glycerol, characterized by peculiar cocoon/open nanocontainer-type morphologies, varieties of oxygen containing groups, and remarkably high specific surface area, is suitable for precursing such hybrids. AA can change crystallization processes and particle morphologies by terminating chain linkages in TiG structure, which increases porosity and brings about visible light responsive photocatalysis for the dyadic hybrid. Benefiting from good adsorption affinity to organic sacrifiers, the sacrifier-prestored hybrid can catalyze significantly enhanced photoreduction with good reproducibility toward dye molecules via the synergy of sacrifier enrichment and photocatalysis. AA modified TiG also exhibits good self-reducibility enabling pre-loading of highly dispersed and localized platinum nanoparticles, and the resulted dyadic hybrid facilitates photocatalytic hydrogen production of extremely higher turn-off frequency and better impurities interference-resistivity compared to the P25-based commercial catalyst.


Assuntos
Nanopartículas Metálicas , Titânio , Catálise , Fotólise , Platina , Reprodutibilidade dos Testes
7.
Front Surg ; 9: 1067306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684182

RESUMO

Background: Total knee arthroplasty (TKA) is recommended for haemophilic patients with end-stage arthritis. TKA combined with a one-stage extraarticular osteotomy is uncommon in the treatment of haemophilic arthritis (HA) with severe extra-articular deformities (EADs) and a history of inhibitors under the guidance of a patient-specific cutting guide (PSI). Case presentation: We reported a 20-year-old male patient with severe haemophilia, limited knee functionality, a 30° sagittal deformity on the femoral side and a history of inhibitors. We adopted the Van Creveld protocol to decrease the inhibitors. TKA and extra-articular osteotomy (EAO) were performed simultaneously and sequentially under the guidance of PSI. An appropriate central alignment of the lower limb was restored by using cement prostheses with antibiotics and femur shaft locking compression plates. The last follow-up showed that the knee function was good, the VAS score was 0, the WOMAC score was 18 and the ROM was 0°-95°. Conclision: Regular haematology management can reduce the perioperative bleeding risk in haemophilic patients treated with inhibitors. PSI plays an important role in guiding the TKA and EAO of end-stage HA patients with severe EAD.

8.
ACS Omega ; 4(8): 12995-13004, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31460426

RESUMO

Silicalite-1-type zeolites with unique intracrystal holes or cracks were successfully prepared using a cellulose nanofiber (CNF) as an additional mediating material, and their vapor phase adsorption properties toward methyl tert-butyl ether (MTBE) and n-nitrosodimethylamine (NDMA) were examined. It was found that the mixing protocol of CNF and structure-directing agents (SDAs), the addition amount of CNF, and the CNF/SDAs amount ratio play important roles in forming the holed silicalite-1. The synthesis route that preliminarily mixes CNF with SDAs in a series of controlled conditions is particularly beneficial for the formation of the holed silicalite-1 with mesoporosity and larger pores because the CNF-SDAs composite structure benefits the zeolite growth closely encompassing CNF inside the crystal structure. It also promotes the preferential formation of the orthorhombic phase vicinal to the CNF surface, namely, the surface of the formed internal holes or cracks, with the twin-type crystal size reduced as compared to the non-CNF-templated sample. On the contrary, the synthesis route that mixes CNF with SDAs-silicate composite ions tends to modify the twin-type crystal shape at the same time to form small but uniform well-crystallized particles with less holes or cracks and a dominative monoclinic phase. It was considered that both the inter-subunit structural defect and silanol defect whose content is increased with CNF addition influence the adsorptivity of MTBE and NDMA. Owing to the small twin-type crystal size, the smaller crystal subunits, and the favored short path from the surface of internal holes or cracks, the holed silicalite-1 derived from the CNF and SDA premixture assures the easiest access of adsorbate molecules to the most energetically favored sites and is most appropriate for the adsorption of both MTBE and NDMA among the examined zeolites.

9.
Sci Rep ; 9(1): 1387, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718694

RESUMO

Multiple sclerosis (MS) is an autoimmune disease characterized by multiple lesions in the brain and spinal cord. We used RNA sequencing to identify microbial sequences and characterize human gene expression patterns in 30 human brain biopsy specimens. RNAs which aligned to known microbial taxa, were significantly enriched in 10 of 12 primary demyelination (MS) brain specimens compared to a group of 15 epilepsy controls, leading to a list of 29 MS microbial candidate genera from 11 different phyla. Most of the candidate MS microbes are anaerobic bacteria. While there were some shared candidates, each of the 10 MS samples with significant microbial RNA enrichment had a distinct set microbial candidates. The fraction of microbial sequencing reads was greater for the MS group (128.8 PPM) compared to the controls (77.4 PPM, p = 0.016). Bacterial peptidoglycan was demonstrated in brain tissue sections from several MS subjects. Human gene expression analysis showed increased expression of inflammation-related pathways in the MS group. This data shows that demyelinating brain lesions are associated with the presence of microbial RNA sequences and bacterial antigen. This suggests that MS is triggered by the presence of a diverse set of microbes within a lesion.


Assuntos
Antígenos de Bactérias/metabolismo , Encéfalo/microbiologia , Encéfalo/patologia , Parede Celular/metabolismo , Doenças Desmielinizantes/microbiologia , Adolescente , Adulto , Idoso , Feminino , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Esclerose Múltipla/microbiologia , Esclerose Múltipla/patologia , Filogenia , Adulto Jovem
10.
Chem Rec ; 19(7): 1393-1406, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30548140

RESUMO

The enhancement of photocatalytic activity of TiO2 can be made either by promoting absorption efficiency of photon energy or by reducing recombination losses of photogenerated charge carriers, for which fabrication of nanocomposite structure with carbon materials is an optional selection. Among various nanocarbons, graphene (G), graphene oxide (GO), and reduced graphene oxide (rGO) are more favorable as the counterpart materials because they can provide availability of both obverse and reverse surface, thus doubling effective sites for adsorption, loading of nanoparticles, and interfacial interaction with the loaded nanoparticles. Composition of G/GO with titania, therefore, is a hopeful strategy for achieving synergy or cooperative effect in photocatalysis. In this personal account, we focus on the background and methodology of several soft chemical approaches that we have utilized up to date to fabricate nanocomposites of G/GO and titania, aiming to shed light on the importance of designing of nanocomposite structure for enhancing photocatalysis. In addition, we emphasize the role of interfacial interaction between carbon and titania by exemplifying a hybridized photocatalyst based on inexpensive biomass-derived carbon sphere (CS), and demonstrate that it is a crucial influential factor underlying an enhanced visible light photocatalysis. CS can be a better selection as a counterpart component than G/GO, whose core-shell composing structure with titania (TiO2 @CS) can efficiently induce charge transfer so as to achieve a much higher photocatalytic performance under visible light illumination as compared to the composite of rGO and titania.

11.
J Environ Manage ; 162: 326-33, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26265601

RESUMO

This investigation evaluated the adsorption behavior of the antiviral drugs of oseltamivir (OE) and its metabolites (i.e., oseltamivir carboxylate (OC)) on three types of carbon nanotubes (CNTs) including single-walled CNT (SWCNT), multi-walled CNT (MWCNT), and carboxylated SWCNT (SWCNT-COOH). CNTs can efficiently remove more than 90% of the OE and OC from aqueous solution when the initial concentration was lower than 10(-4) mmol/L. The Polanyi-Manes model depicted the adsorption isotherms of OE and OC on CNTs better than the Langmuir and Freundlich models. The properties of OE/OC and the characteristics of CNTs, particularly the oxygen functional groups (e.g., SWCNT-COOH) played important roles during the adsorption processes. OE showed a higher adsorption affinity than OC. By comparing the different adsorbates adsorption on each CNT and each adsorbate adsorption on different CNTs, the adsorption mechanisms of hydrophobic interaction, electrostatic interaction, van der Waals force, and H-bonding were proposed as the contributing factors for OE and OC adsorption on CNTs. Particularly, for verifying the contribution of electrostatic interaction, the changes of adsorption partition efficiency (Kd) of OE and OC on CNTs were evaluated by varying pH from 2 to 11 and the importance of isoelectric point (pHIEP) of CNTs on OE and OC adsorption was addressed.


Assuntos
Antivirais/química , Poluentes Ambientais/química , Nanotubos de Carbono/química , Oseltamivir/análogos & derivados , Adsorção , Ácidos Carboxílicos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Oseltamivir/química
12.
Nanotoxicology ; 9(3): 404-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25976321

RESUMO

An international symposium for nanosafety was held recently at the Nanyang Technological University in Singapore. Topics relating to understanding nanomaterial properties, tools, and infrastructure required for predicting hazardous outcomes, measuring nanomaterial exposure levels, systems approach for risk assessment and public's perception of nanotechnology were covered. The need for a multidisciplinary approach, across both natural and social sciences, for developing sustainable nanotechnology solutions was heavily emphasized. This commentary highlights the major issues discussed and the commitment of the nanosafety research community in Singapore to contribute collectively to realise the vision of sustainable nanotechnology.


Assuntos
Nanoestruturas/toxicidade , Nanotecnologia , Segurança
13.
Cardiovasc Ther ; 33(3): 118-26, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25825053

RESUMO

INTRODUCTION: The relationship between the beneficial effects of pioglitazone in reducing clinical events and plaque inflammatory burden remains unknown. This study aimed to determine whether pioglitazone can reduce the number of plaque thrombosis incidences and whether decreasing plaque inflammation is the mechanism by which pioglitazone reduces plaque thromboses. METHODS AND RESULTS: therosclerotic rabbits were divided into two groups: the atherosclerosis group (n = 13) and pioglitazone group (n = 10). The rabbits underwent pharmacological triggering to induce thrombosis. Serum inflammatory markers, FDG uptake, macrophage, and neovessel staining detected arterial inflammation. PET/CT scans were performed twice (baseline and posttreatment scans). Plaque area, macrophages, and neovessels were measured and the histologic sections were matched with the PET/CT scans. Serum MMP-9 and hsCRP were lower in the pioglitazone group compared to the atherosclerosis group. The SUVmean significantly decreased in the pioglitazone group (0.62 ± 0.21 vs. 0.55 ± 0.19, P = 0.008), but increased in the atherosclerosis group (0.61 ± 0.15 vs. 0.91 ± 0.20, P < 0.000). The incidence rate of plaque rupture, plaque area, macrophage density, and neovessel density was significantly lower in rabbits with pioglitazone than without (15% vs. 38%, P < 0.001; 18.00 ± 2.30 vs. 27.00 ± 1.60; P < 0.001; 8.80 ± 3.94 vs. 28.26 ± 2.49; P < 0.001; 16.50 ± 3.09 vs. 29.00 ± 2.11; P < 0.001, respectively). Moreover, plaque area and macrophage density were positively correlated with SUV values. CONCLUSIONS: Our study suggests that pioglitazone can reduce the number of plaque thrombosis incidences by decreasing plaque inflammation. (18)F-FDG-PET/CT can detect plaque inflammation and assess the effects of antiatherosclerotic drugs.


Assuntos
Hipoglicemiantes/farmacologia , Inflamação/tratamento farmacológico , Placa Aterosclerótica/tratamento farmacológico , Tiazolidinedionas/farmacologia , Trombose/prevenção & controle , Animais , Biomarcadores , Glicemia , Proteína C-Reativa/metabolismo , Fluordesoxiglucose F18 , Lipídeos/sangue , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pioglitazona , Tomografia por Emissão de Pósitrons , Coelhos , Tomografia Computadorizada por Raios X
14.
Chemosphere ; 131: 41-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25765262

RESUMO

The photocatalytic degradation of the antiviral drug Tamiflu (oseltamivir phosphate, OP) by TiO2 - P25, ST-01 and ATO was investigated in aqueous solution under ultraviolet (UV-A) irradiation. The photocatalysis of OP is well described by pseudo-first-order kinetics with r2>98.0% for all cases. The kinetic constant of P25 with 80% anatase and 20% rutile (0.040 min(-1)) is 4 and 10 times higher than that of ATO and ST-01 with 100% purity of anatase, respectively. We examined the effects of the catalyst loading and initial OP concentration on the photodegradation of OP, and used potassium iodine, isopropanol, and calcium fluorine as radical quenchers to evaluate the contributions of the hydroxyl radical (OH) and photo hole (h+) in the photodegradation. Results confirmed that 80% of the contribution came from the OH species. Although more than 95% of the OP (21 µM) was removed after 80 min of UV-A irradiation with 20 and 100 mg L(-1) P25, the removal efficiencies of total organic carbon (TOC) were only 45.6% and 67.0%, respectively, after 360 min UV-A irradiation. Based on an intermediate analysis by HPLC coupled with a triple quadrupole spectrometer and an ion trap mass spectrometer, typical intermediate species such as hydration derivatives, hydroxyl substitutes and keto-derivatives were identified and possible degradation pathways of OP by P25 were proposed.


Assuntos
Antivirais/análise , Oseltamivir/análise , Fotólise , Titânio/química , Poluentes Químicos da Água/análise , Antivirais/química , Antivirais/efeitos da radiação , Catálise , Cinética , Modelos Teóricos , Estrutura Molecular , Oseltamivir/química , Oseltamivir/efeitos da radiação , Raios Ultravioleta , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação
15.
Int J Biol Macromol ; 64: 377-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24370476

RESUMO

To evaluate the immunomodulating responses in intestine, spleen and liver, 50-200mg/kg of DHP was orally administrated to mice without or with methotrexate. The proliferation of marrow cells, which was performed with the addition of the supernatant of small intestinal lymphocytes isolated from the mice administrated orally with DHP, showed that the intestinal immune response was significantly enhanced in all DHP-treated groups. For the immune response in spleen, all tested doses of DHP remarkably promoted the proliferation of splenic cells and increased the secretion of interferon-γ (IFN-γ). For the immune responses in liver, DHP not only significantly stimulated the proliferation of hepatic cells and the secretion of IFN-γ at all tested doses of DHP, but also significantly elevated the secretion interleukin-4 (IL-4) at the doses of 100 and 200mg/kg. Moreover, DHP could recover methotrexate-injured small intestinal immune function (100 and 200mg/kg) and promoted cell proliferation and IFN-γ production (200mg/kg) in spleen and liver of methotrexate-treated mice. These results suggested that DHP after oral administration possessed immunomodulating effects both in small intestine immune system and in systemic immune system, which were further proved by the mRNA expression of IFN-γ and IL-4.


Assuntos
Dendrobium/química , Fatores Imunológicos/farmacologia , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Polissacarídeos/farmacologia , Baço/efeitos dos fármacos , Animais , Citocinas/biossíntese , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Intestinos/imunologia , Fígado/imunologia , Masculino , Metotrexato/farmacologia , Camundongos , Polissacarídeos/administração & dosagem , Polissacarídeos/química , Baço/imunologia
16.
Acta Pharmacol Sin ; 34(11): 1374-80, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24122008

RESUMO

MicroRNAs (miRNAs) are small non-coding RNA molecules, whose primary function is to regulate gene expression at the post-transcriptional/translational levels. MiRNAs play crucial roles in normal biological processes and are commonly dys-regulated in human diseases. Stem cells are regarded as the "mother" cells of all types of differentiated cells that comprise tissues and organs of the body. A novel hypothesis proposes that tumors are composed of heterogeneous cells derived from cancer stem cells, which have self-renewal and differentiation capabilities similar to those of normal stem cells. Cancer stem cells have been isolated and characterized from various tumors. Given recent studies supporting the critical regulatory roles of miRNAs in the self-renewal and differentiation of cancer stem cells, better understanding the functions of miRNAs will provide invaluable insights into the prevention of tumorigenesis and tumor progression. In this review, we will summarize the research progress in the study of miRNAs involved in the self-renewal and differentiation of cancer stem cells.


Assuntos
MicroRNAs/genética , Neoplasias/patologia , Células-Tronco Neoplásicas/metabolismo , Animais , Diferenciação Celular , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/genética , Processamento Pós-Transcricional do RNA
17.
Pediatr Res ; 73(5): 612-620, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23419538

RESUMO

BACKGROUND: We showed that intrauterine growth restriction (IUGR) increases distal airspace wall thickness at birth (postnatal age 0; P0) in rat pups (saccular stage of lung development). However, that report did not assess whether the saccular phenotype persisted postnatally or occurred in males or females, nor did the report identify a potential molecular pathway for the saccular phenotype at P0. We hypothesized that IUGR persistently delays alveolar formation and disrupts retinoic acid receptor (RAR) mRNA and protein levels in the lung of rat pups in a postnatal age- and sex-specific manner. METHODS: IUGR was induced in pregnant rats by bilateral uterine artery ligation. Alveolar formation and expression of RARα, -ß, and -γ were quantified at P0, P6 (alveolar stage), and P21 (postalveolarization). RESULTS: IUGR increased distal airspace wall thickness in female pups at P0 only. IUGR did not affect male pups at any age. IUGR transiently increased lung RAR-ß protein abundance, which inhibits alveolar formation, at P0 in female pups. Serum retinol concentration was normal at all ages. CONCLUSION: IUGR alone is not sufficient to persistently delay postnatal alveolar formation or disrupt expression of RARs. We speculate that for IUGR to delay alveolar formation postnatally, a second insult is necessary.


Assuntos
Retardo do Crescimento Fetal , Pulmão/metabolismo , Alvéolos Pulmonares/embriologia , Receptores do Ácido Retinoico/metabolismo , Animais , Feminino , Pulmão/embriologia , Gravidez , Ratos
18.
IEEE Trans Image Process ; 21(10): 4322-33, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22829405

RESUMO

In image processing, nonconvex regularization has the ability to smooth homogeneous regions and sharpen edges but leads to challenging computation. We propose some iterative schemes to minimize the energy function with nonconvex edge-preserving potential. The schemes are derived from the duality-based algorithm proposed by Bermúdez and Moreno and the fixed point iteration. The convergence is proved for the convex energy function with nonconvex potential and the linear convergence rate is given. Applying the proposed schemes to Perona and Malik's nonconvex regularization, we present some efficient algorithms based on our schemes, and show the approximate convergence behavior for nonconvex energy function. Experimental results are presented, which show the efficiency of our algorithms, including better denoised performance of nonconvex regularization, faster convergence speed, higher calculation precision, lower calculation cost under the same number of iterations, and less implementation time under the same peak signal noise ratio level.

19.
Aging Cell ; 11(3): 456-66, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22296597

RESUMO

RECQL4 is associated with Rothmund-Thomson Syndrome (RTS), a rare autosomal recessive disorder characterized by premature aging, genomic instability, and cancer predisposition. RECQL4 is a member of the RecQ helicase family, and has many similarities to WRN protein, which is also implicated in premature aging. There is no information about whether any of the RecQ helicases play roles in mitochondrial biogenesis, which is strongly implicated in the aging process. Here, we used microscopy to visualize RECQL4 in mitochondria. Fractionation of human and mouse cells also showed that RECQL4 was present in mitochondria. Q-PCR amplification of mitochondrial DNA demonstrated that mtDNA damage accumulated in RECQL4-deficient cells. Microarray analysis suggested that mitochondrial bioenergetic pathways might be affected in RTS. Measurements of mitochondrial bioenergetics showed a reduction in the mitochondrial reserve capacity after lentiviral knockdown of RECQL4 in two different primary cell lines. Additionally, biochemical assays with RECQL4, mitochondrial transcription factor A, and mitochondrial DNA polymerase γ showed that the polymerase inhibited RECQL4's helicase activity. RECQL4 is the first 3'-5' RecQ helicase to be found in both human and mouse mitochondria, and the loss of RECQL4 alters mitochondrial integrity.


Assuntos
DNA Mitocondrial/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , RecQ Helicases/genética , RecQ Helicases/metabolismo , Fatores Etários , Idoso de 80 Anos ou mais , Animais , Fracionamento Celular/métodos , Linhagem Celular Tumoral , Dano ao DNA , Instabilidade Genômica , Células HeLa , Humanos , Camundongos
20.
Mol Plant ; 5(4): 889-900, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22138860

RESUMO

An increasing number of microRNAs (miRNAs) have been shown to play crucial regulatory roles in the process of plant development. Here, we used high-throughput sequencing combined with computational analysis to characterize miRNAomes from the ovules of wild-type upland cotton and a fiberless mutant during fiber initiation. Comparative miRNAome analysis combined with northern blotting and RACE-PCR revealed seven fiber initiation-related miRNAs expressed in cotton ovules and experimentally validated targets of these miRNAs are involved in different cellular responses and metabolic processes, including transcriptional regulation, auxin and gibberellin signal transduction, actin bundles, and lignin biosynthesis. This paper describes a complex regulatory network consisting of these miRNAs expressed in cotton ovules to coordinate fiber initiation responses. In addition, 36 novel miRNAs and two conserved miRNAs were newly identified, nearly doubling the number of known cotton miRNA families to a total of 78. Furthermore, a chromatin remodeling complex subunit and a pre-mRNA splicing factor are shown for the first time to be miRNA targets. To our knowledge, this study is the first systematic investigation of fiber initiation-related miRNAs and their targets in the developing cotton ovule, deepening our understanding of the important regulatory functions of miRNAs in cotton fiber initiation.


Assuntos
Fibra de Algodão , Perfilação da Expressão Gênica , Gossypium/crescimento & desenvolvimento , Gossypium/genética , MicroRNAs/genética , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/genética , Sequência de Bases , Gossypium/metabolismo , Mutação , Óvulo Vegetal/metabolismo , Análise de Sequência de RNA
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