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1.
J Hered ; 115(3): 292-301, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38364316

RESUMO

Biodiversity conservation is a top priority in the face of global environmental change, and the practical restoration of biodiversity has emerged as a key objective. Nevertheless, the question of how to effectively contribute to biodiversity restoration and identify suitable systems for such efforts continues to present major challenges. By using genome-wide SNP data, our study revealed that populations from different mountain ranges of the Formosan Long-Arm Scarab beetle, a flagship species that receives strict protection, exhibited a single genetic cluster with no subdivision. Additionally, our result implied an association between the demographic history and historical fluctuations in climate and environmental conditions. Furthermore, we showed that, despite a stable and moderately sized effective population over recent history, all the individuals we studied exhibited signs of genetic inbreeding. We argued that the current practice of protecting the species as one evolutionarily significant unit remains the best conservation plan and that recent habitat change may have led to the pattern of significant inbreeding. We closed by emphasizing the importance of conservation genetic studies in guiding policy decisions and highlighting the potential of genomic data for identifying ideal empirical systems for genetic rescue, or assisted gene flow studies.


Assuntos
Besouros , Conservação dos Recursos Naturais , Genética Populacional , Endogamia , Densidade Demográfica , Animais , Besouros/genética , Polimorfismo de Nucleotídeo Único , Ecossistema , Fluxo Gênico , Genômica/métodos , Variação Genética , Biodiversidade
2.
Syst Parasitol ; 101(2): 11, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193933

RESUMO

Trematodes of the genus Mesocoelium Odhner, 1910 (Digenea: Plagiorchioidea: Mesocoeliidae) are globally distributed and parasitize amphibians, reptiles, or occasionally fishes. This genus is one of the most confusing taxa in trematodes because of its poor morphological features. In this study, we examined species of Mesocoelium collected from Japanese amphibians and found that they can be morphologically assigned to two species of Mesocoelium. Mesocoelium brevicaecum Ochi in Goto and Ozaki, 1929 parasitizes various both urodelan and anuran amphibians and occurred widely in Japan, while M. japonicum Goto and Ozaki, 1930 parasitizes a few hynobiid species in a limited part of Japan. We proposed ceca length as a valid key characteristic for species identification in this genus. M. elongatum Goto and Ozaki, 1929, M. lanceatum Goto and Ozaki, 1929, M. minutum Park, 1939, M. ovatum Goto and Ozaki, 1930, and M. pearsei Goto and Ozaki, 1930 are junior synonyms of M. brevicaecum, while M. japonicum can be distinguishable from them by morphologically and molecularly. Our molecular study supported the validity of both species and showed intraspecific divergence associated with geographic distance. Molecular identification suggests that the land snail Euhadra quaesita can serve as the first intermediate host for M. japonicum in Japan. This study also indicates the extremely low specificity of this genus for vertebrate hosts. Finally, we conclude that at least three species of Mesocoelium (M. brevicaecum, M. japonicum, and Mesocoelium sp. 1) are distributed in Japan. Further studies in other regions are undoubtedly required for a better understanding of the taxonomy and ecology of the genus Mesocoelium.


Assuntos
Anuros , Trematódeos , Animais , Japão , Especificidade da Espécie , Trematódeos/genética , Ciclofosfamida
3.
Mol Phylogenet Evol ; 155: 106999, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33130300

RESUMO

East Asia has highly diverse and endemic biota due to its complex geological and climatic history and its diversified topography. The continental and insular distributions of land snail genus Acusta in East Asia provide a good opportunity to compare the evolutionary processes in this group under different biogeographical conditions. In this study, we inferred the evolutionary history of the land snail genus Acusta by a molecular phylogeny and investigated how the palaeogeographic events shaped species diversity and the distribution of the Acusta genus within the island arc. A concatenated dataset generated from sequences of one nuclear (ITS2) and two mitochondrial (16S, COI) gene fragments, include most of nominal taxa of the genus, four related species and one outgroup. We constructed the phylogeny and the evolutionary history of the genus through maximum-likelihood and Bayesian inference methods, using a Bayesian molecular clock and ancestral range estimation. Our results suggested that currently recognized species in Acusta are polyphyletic. The traditionally accepted concept of the affinity of Acusta and Bradybaena is not supported. The hypothesis of colonization via land bridges during the Pleistocene glaciations for the biota of East Asian islands is not supported. Instead, the origin and diversification of the genus Acusta was dated to the late Miocene-Pliocene from an area around North and Northeast China to South China and East Asian islands Three major evolutionary lineages were identified. Two of the major lineages demonstrate distinct evolutionary histories, as sympatric speciation is the major speciation process for the continental clade, while the insular clade originated from founder events. Taiwan functioned as an important source of diversification for species on the East Asian islands possibly through passive dispersal of different mechanisms. The sea level fluctuations caused by the Pleistocene glacial cycles play a role in the subsequent dispersion and diversification of species of the continental clade, such as the more recent range expansion of A. redfieldi from South China to Taiwan and Japan.


Assuntos
Biodiversidade , Filogeografia , Caramujos/classificação , Animais , Teorema de Bayes , Calibragem , Núcleo Celular/genética , Ásia Oriental , Genes Mitocondriais , Ilhas , Filogenia , Caramujos/genética , Fatores de Tempo
4.
J Anim Ecol ; 90(4): 967-977, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33481265

RESUMO

The level of dentition asymmetry in snail-eating snakes may reflect their prey choice and feeding efficiency on asymmetric land snails. The three species of Pareas snakes (Squamata: Pareidae) in Taiwan, which form partially sympatric distribution on the island, provide a potential case to test the hypothesis of niche partitioning and character displacement with regard to dentition asymmetry and specialisation in feeding behaviour. In this study, behavioural experiments confirmed that P. formosensis feeds exclusively on slugs, whereas P. atayal and P. komaii consumed both. However, P. atayal more efficiently preys on land snails than P. komaii, exhibiting a shorter handling time and fewer mandibular retractions. Micro-CT and ancestral character reconstruction demonstrated the lowest asymmetry in P. formosensis (the slug specialist), the highest dentition asymmetry in P. atayal (the land snail specialist) and flexibility in P. komaii (the niche switcher): increased dentition asymmetry when sympatrically distributed with the slug eater (character displacement), and decreased asymmetry when living alone (ecological niche release). Ecological niche modelling showed that the distribution of P. formosensis is associated with the presence of slugs, while that of P. atayal could be explained by the land snails. Combining the results from morphology, phylogeny, behavioural experiments and ecological niche modelling, we showed that competition in the sympatric region might have facilitated character displacement among congeners, while the absence of competition in allopatric region has led to ecological niche release.


Assuntos
Dentição , Serpentes , Animais , Ecossistema , Caramujos , Taiwan
5.
Neoplasma ; 68(5): 1113-1117, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34459209

RESUMO

The evaluation and management of papillary thyroid microcarcinoma (PTMC) have always been challenging and controversial. Our retrospective study aimed to investigate the metastatic trend and risk factors of cN0 papillary thyroid microcarcinoma patients and provide advice for surgical strategies. The clinicopathological features of 556 cN0 PTMC patients undergoing thyroidectomy combined with central compartment dissection (CCD) were compared by the χ2 test and risk factors were identified by binary logistic regression analysis. Numbers of dissected lymph nodes (DLN) and metastatic lymph nodes (MLN) were analyzed using the Mann-Whitney U test to compare metastatic trends between different lobes. Male gender, tumor maximum diameter (TMD) larger than 5 mm, multifocality, and capsular/extracapsular invasion were metastatic risk factors of central compartment metastasis (CCM) (p<0.05). The number of DLN in the right level VI was larger than in the left (p<0.05), while the number of MLN was similar (p>0.05). The chance of CCM was higher when the number of DLN was larger than 5 (p<0.05). After identified metastatic trends and risk factors, we recommend surgery for patients deciding on aggressive treatment, especially for cases where a combination of risk factors is present. And to ensure no residual metastatic lymph nodes and reduce secondary surgery rates, adequate lymphadenectomy on the diseased side would be a better choice considering the standard of care.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Carcinoma Papilar/cirurgia , Humanos , Linfonodos/cirurgia , Metástase Linfática , Masculino , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/cirurgia
6.
J Med Ultrasound ; 26(4): 200-204, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30662151

RESUMO

PURPOSE: This study sought to determine the association between twinkling artifacts on color Doppler ultrasound and different types of guidewires. MATERIALS AND METHODS: Twenty-two commonly used guidewires were classified into three groups according to decreasing diameter (Group 1, 0.035"; Group 2, 0.018"; and Group 3, 0.014") and tested in vitro. Severity of twinkling was visually graded into four categories (0-3, from weak to strong). RESULTS: The percentages (tips/shafts) of twinkling artifacts were 100%/100% for Group 1; 0%/33.3% for Group 2; and 18.8%/31% for Group 3. The mean scores (tips/shafts) were 2.3/2.7 for Group 1; 0/0.3 for Group 2; and 0.3/0.4 for Group 3. Among them, both two guidewires with strong twinkling artifacts (score = 3) exhibited extensive rough surfaces on microscopic pictures. CONCLUSION: The twinkling artifacts were more likely to present in guidewires with larger diameters (from 0.014" to 0.035") in our study settings. The surface roughness may be the contribution to the twinkling artifact. Internal heterogeneities, such as types of material, types of coating, tip loading, and spring coil length, do not show influence on the twinkling artifact.

7.
Am J Physiol Regul Integr Comp Physiol ; 313(4): R473-R486, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28724546

RESUMO

High-protein diet (HPD) curtails obesity and/or fat mass, but it is unknown whether it reverses neuroinflammation or alters glucose levels, CCK sensitivity, and gut microbiome in rats fed a Western diet (WD)-induced obesity (DIO). Male rats fed a WD (high fat and sugar) for 12 wk were switched to a HPD for 6 wk. Body composition, food intake, meal pattern, sensitivity to intraperitoneal CCK-8S, blood glucose, brain signaling, and cecal microbiota were assessed. When compared with a normal diet, WD increased body weight (9.3%) and fat mass (73.4%). CCK-8S (1.8 or 5.2 nmol/kg) did not alter food intake and meal pattern in DIO rats. Switching to a HPD for 6 wk reduced fat mass (15.7%) with a nonsignificantly reduced body weight gain, normalized blood glucose, and decreased feeding after CCK-8S. DIO rats on the WD or switched to a HPD showed comparable microbial diversity. However, in HPD versus WD rats, there was enrichment of 114 operational taxonomic units (OTUs) and depletion of 188 OTUs. Of those, Akkermansia muciniphila (enriched on a HPD), an unclassified Clostridiales, a member of the RF39 order, and a Phascolarctobacterium were significantly associated with fat mass. The WD increased cytokine expression in the hypothalamus and dorsal medulla that was unchanged by switching to HPD. These data indicate that HPD reduces body fat and restores glucose homeostasis and CCK sensitivity, while not modifying brain inflammation. In addition, expansion of cecal Akkermansia muciniphila correlated to fat mass loss may represent a potential peripheral mechanism of HPD beneficial effects.


Assuntos
Encéfalo/efeitos dos fármacos , Ceco/efeitos dos fármacos , Colecistocinina/farmacologia , Proteínas Alimentares/farmacologia , Encefalite/metabolismo , Microbiota/efeitos dos fármacos , Obesidade/microbiologia , Animais , Glicemia/metabolismo , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Ceco/metabolismo , Ceco/microbiologia , Citocinas/metabolismo , Dieta Ocidental , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Obesidade/metabolismo , Ratos , Ratos Sprague-Dawley
8.
Soft Matter ; 11(20): 3971-6, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25833300

RESUMO

Natural polymeric hydrogels with self-healing capability that can recover the functionalities and structures of gels after damage are extremely attractive due to their emerging applications in the biomedical field. Here we report a self-healable polymeric hydrogel by self-crosslinking two natural polymers acrylamide-modified chitin (AMC) containing amino groups and oxidized alginate containing dialdehyde groups. The generation of the self-crosslinked hydrogel relies on the dynamic covalent linkage through Schiff base between the polysaccharide chains. The self-healing capability of the crosslinked hydrogel depends on the molar ratio of AMC and oxidized alginate and the surrounding pH. Under certain circumstances, the damaged hydrogel shows a complete recovery and can be stretched to a favorable extent, which is seldom observed for polysaccharide self-healing hydrogel. Notably, we find that the self-healing ability can be "stored" by freeze-drying and "activated" by rehydration. In addition, we demonstrate that the hydrogel can be used as a soft template to guide the repair of inorganic materials like hydroxyapatite. We anticipate that this self-healable hydrogel consisting of biocompatible and biodegradable polysaccharides can be applied to various biomedical fields.

9.
Aging (Albany NY) ; 16(7): 6488-6509, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579171

RESUMO

BACKGROUND: Thyroid cancer represents the most prevalent malignant endocrine tumour, with rising incidence worldwide and high mortality rates among patients exhibiting dedifferentiation and metastasis. Effective biomarkers and therapeutic interventions are warranted in aggressive thyroid malignancies. The transcription factor 19 (TCF19) gene has been implicated in conferring a malignant phenotype in cancers. However, its contribution to thyroid neoplasms remains unclear. RESULTS: In this study, we performed genome-wide and phenome-wide association studies to identify a potential causal relationship between TCF19 and thyroid cancer. Our analyses revealed significant associations between TCF19 and various autoimmune diseases and human cancers, including cervical cancer and autoimmune thyroiditis, with a particularly robust signal for the deleterious missense variation rs2073724 that is associated with thyroid function, hypothyroidism, and autoimmunity. Furthermore, functional assays and transcriptional profiling in thyroid cancer cells demonstrated that TCF19 regulates important biological processes, especially inflammatory and immune responses. We demonstrated that TCF19 could promote the progression of thyroid cancer in vitro and in vivo and the C>T variant of rs2073724 disrupted TCF19 protein binding to target gene promoters and their expression, thus reversing the effect of TCF19 protein. CONCLUSIONS: Taken together, these findings implicate TCF19 as a promising therapeutic target in aggressive thyroid malignancies and designate rs2073724 as a causal biomarker warranting further investigation in thyroid cancer.


Assuntos
Polimorfismo de Nucleotídeo Único , Neoplasias da Glândula Tireoide , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Tireoidite/genética
10.
Int J Artif Organs ; 47(2): 96-106, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38186004

RESUMO

OBJECTIVE: To systematically evaluate the clinical efficacy of pulmonary rehabilitation in patients with mechanical ventilation in an intensive care unit (ICU). METHODS: Relevant studies were identified in the PubMed, Web of Science, National Library of Medicine, China National Knowledge Infrastructure and Wanfang databases. A meta-analysis was performed after screening based on the inclusion and exclusion criteria, data extraction and literature quality evaluation. RESULTS: In total, 19 studies involving 2181 participants were included. The results of the meta-analysis revealed that compared with patients with conventional rehabilitation measures, patients with pulmonary rehabilitation measures had a higher offline success rate (relative risk (RR) = 1.16; 95% confidence interval (CI): 1.09, 1.24; p < 0.00001) and higher arterial oxygen partial pressure levels (mean difference (MD) = 8.96; 95%CI: 5.98, 11.94; p < 0.0001) and these measures significantly shortened the duration of mechanical ventilation (standardised MD (SMD) = -1.08; 95%CI: -1.58, -0.59; p < 0.0001) and ICU stay (SMD = -1.41; 95%CI: -1.94, -0.88; p < 0.0001). Aspiration significantly reduced the incidence of ventilator-associated pneumonia (RR = 0.35; 95%CI: 0.24, 0.51; p < 0.00001) and deep vein thrombosis (RR = 0.32; 95%CI: 0.13, 0.76; p = 0.01) in ICU patients with mechanical ventilation. CONCLUSION: Pulmonary rehabilitation measures can improve the success rate of weaning from mechanical ventilation in ICU patients, shorten the time of mechanical ventilation and ICU hospitalisation and reduce the incidence of related adverse reactions, but the impact on mortality requires further study.


Assuntos
Pneumonia Associada à Ventilação Mecânica , Respiração Artificial , Humanos , Respiração Artificial/efeitos adversos , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Unidades de Terapia Intensiva , Cuidados Críticos , Resultado do Tratamento
11.
Int J Biol Macromol ; 239: 124264, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37003384

RESUMO

Due to their large specific surface area and numerous diffusion channels, hollow fibers are widely used in wastewater treatment. In this study, we successfully synthesized a chitosan (CS)/polyvinylpyrrolidone (PVP)/polyvinyl alcohol (PVA) hollow nanofiber membrane (CS/PVP/PVA-HNM) via coaxial electrospinning. This membrane demonstrated remarkable permeability and adsorption separation. Specifically, the CS/PVP/PVA-HNM had a pure water permeability of 4367.02 L·m-2·h-1·bar-1. The hollow electrospun nanofibrous membrane exhibited a continuous interlaced nanofibrous framework structure with the extraordinary advantages of high porosity and high permeability. The rejection ratios of CS/PVP/PVA-HNM for Cu2+, Ni2+, Cd2+, Pb2+, malachite green (MG), methylene blue (MB) and crystal violet (CV) were 96.91 %, 95.29 %, 87.50 %, 85.13 %, 88.21 %, 83.91 % and 71.99 %, and the maximum adsorption capacities were 106.72, 97.46, 88.10, 87.81, 53.45, 41.43, and 30.97 mg·g-1, respectively. This work demonstrates a strategy for the synthesis of hollow nanofibers, which provides a novel concept for the design and fabrication of highly efficient adsorption and separation membranes.


Assuntos
Quitosana , Metais Pesados , Nanofibras , Quitosana/química , Nanofibras/química , Álcool de Polivinil/química , Povidona , Corantes
12.
RSC Adv ; 13(16): 10592-10599, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37025671

RESUMO

In this study, the interaction mechanism of bovine serum albumin (BSA) with tannic acid (TA) was investigated by spectroscopic and computational approaches and further validated using circular dichroism (CD), differential scanning calorimetry (DSC) and molecular docking techniques. The fluorescence spectra showed that TA bound to BSA and underwent static quenching at a single binding site, which was consistent with the molecular docking results. And the fluorescence quenching of BSA by TA was dose-dependent. Thermodynamic analysis indicated that hydrophobic forces dominated the interaction of BSA with TA. The results of circular dichroism showed that the secondary structure of BSA was slightly changed after coupling with TA. Differential scanning calorimetry showed that the interaction between BSA and TA improved the stability of the BSA-TA complex, and the melting temperature increased to 86.67 °C and the enthalpy increased to 264.1 J g-1 when the ratio of TA to BSA was 1.2 : 1. Molecular docking techniques revealed specific amino acid binding sites for the BSA-TA complex with a docking energy of -12.9 kcal mol-1, which means the TA is non-covalently bound to the BSA active site.

13.
Nanomaterials (Basel) ; 14(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38202477

RESUMO

Zn-BTC (H3BTC refers to 1, 3, 5-benzoic acid) MOF was used as a self-template and a zinc source to prepare ZnS/NiS2 with a layered heterogeneous structure as a promising electrode material using cation exchange and solid-phase vulcanization processes. The synergistic effect of the two metal sulfides enhances the application of ZnS/NiS2. And the high specific surface area and abundant active sites further promote the mass/charge transfer and redox reaction kinetics. In the three-electrode system, the specific capacitance was as high as 1547 F/g at a current density of 1 A/g, along with satisfactory rate capability (1214 F/g at 6 A/g) and cycling performance. Coupled with activated carbon (AC), the prepared hybrid device (ZnS/NiS2 as the positive electrode and AC as the negative electrode) (ZnS/NiS2/AC) can be operated under a potential window of 1.6 V and provides a high energy density of 26.3 Wh/kg at a power density of 794 W/kg. Notably, the assembled ZnS/NiS2//AC showed little capacity degradation after 5000 charge/discharge cycles.

14.
Mar Drugs ; 10(8): 1852-1872, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23015777

RESUMO

The antitumor activity of pardaxin, a fish antimicrobial peptide, has not been previously examined in in vitro and in vivo systems for treating murine fibrosarcoma. In this study, the antitumor activity of synthetic pardaxin was tested using murine MN-11 tumor cells as the study model. We show that pardaxin inhibits the proliferation of MN-11 cells and reduces colony formation in a soft agar assay. Transmission electron microscopy (TEM) showed that pardaxin altered the membrane structure similar to what a lytic peptide does, and also produced apoptotic features, such as hollow mitochondria, nuclear condensation, and disrupted cell membranes. A qRT-PCR and ELISA showed that pardaxin induced apoptosis, activated caspase-7 and interleukin (IL)-7r, and downregulated caspase-9, ATF 3, SOCS3, STAT3, cathelicidin, p65, and interferon (IFN)-γ suggesting that pardaxin induces apoptosis through the death receptor/nuclear factor (NF)-κB signaling pathway after 14 days of treatment in tumor-bearing mice. An antitumor effect was observed when pardaxin (25 mg/kg; 0.5 mg/day) was used to treat mice for 14 days, which caused significant inhibition of MN-11 cell growth in mice. Overall, these results indicate that pardaxin has the potential to be a novel therapeutic agent to treat fibrosarcomas.


Assuntos
Antineoplásicos/farmacologia , Fibrossarcoma/tratamento farmacológico , Venenos de Peixe/farmacologia , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Fibrossarcoma/patologia , Venenos de Peixe/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Int J Biol Macromol ; 210: 76-84, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35533844

RESUMO

In this work, a novel electrospun chitosan (CS)/polyvinylpyrrolidone (PVP)/polyvinyl alcohol (PVA) nanofibrous membrane was prepared to remove heavy metal ions and organic pollutants from water. The nanofiber morphologies were adjusted through the optimal electrospinning process parameters. Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) characterizations indicated that a well-crosslinked CS/PVP/PVA nanofiber film was formed. Under the optimize conditions, the obtained CS/PVP/PVA nanofiber membranes exhibited porous and uniform nanofibrous structures with an average diameter of 160 nm and a pure water permeability of 4518.91 L·m-2·h-1·bar-1. In addition, the adsorption and separation performance of CS/PVP/PVA nanofiber membranes were evaluated with Cu(II), Ni(II), Cd(II), Pb(II) and Methylene Blue (MB), Malachite Green (MG) as target ions and dyes. The results showed that the retention rate of CS/PVP/PVA nanofiber membranes for Cu(II), Ni(II), Cd(II), Pb(II), MG and MB can reach 94.20%, 90.35%, 83.33%, 80.12%, 84.01% and 69.91%, respectively. The adsorption capacities of Cu(II), Ni(II), Cd(II), Pb(II), MG and MB were 34.79, 25.24, 18.07, 16.05, 17.86 and 13.27 mg g-1. The adsorption kinetics of heavy metal ions and dyes by the nanofiber membranes can be explained by the Langmuir isotherm model and represented by the pseudo-second-order kinetic mechanism that determined the spontaneous chemisorption process. This study provides a synthetic approach to membranes for the removal of organic and heavy metal micropollutants from water.


Assuntos
Quitosana , Poluentes Ambientais , Metais Pesados , Nanofibras , Poluentes Químicos da Água , Adsorção , Cádmio/análise , Quitosana/química , Corantes , Íons , Cinética , Chumbo , Nanofibras/química , Álcool de Polivinil/química , Povidona , Água , Poluentes Químicos da Água/análise
16.
Carbohydr Polym ; 294: 119756, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868783

RESUMO

Nanofibrous membrane have great potential in the field of water purification due to the high porosity and large specific surface area. Herein, a dual layers nanofibrous membrane was prepared by combining an active layer containing carbon nanotubes (CNTs) with a porous chitosan (CS)/polyvinylpyrrolidone (PVP)/polyvinyl alcohol (PVA) nanofibrous support layer via electrospinning-electrospray technique for highly efficient heavy metal and organic pollutants removal. Incorporating CNTs into the active layer offered additional nanochannels which significantly enhanced pure water permeate flux (1533.26 L·m-2·h-1) and heavy metal ions/dyes rejection (Cu2+ 95.68 %, Ni2+ 93.86 %, Cd2+ 88.52 %, Pb2+ 80.41 %, malachite green 87.20 %, methylene blue 76.33 %, and crystal violet 63.39 %). The optimal membranes were formed with a thickness of 20 µm and a roughness of 142 nm while still showing good perm-selectivity compared with commercial PVDF membrane. Moreover, the constructed membrane exhibited good antifouling property and long-term stability during filtration process. This work provides a new strategy to fabricate advanced separation membranes for water treatment.


Assuntos
Quitosana , Metais Pesados , Nanofibras , Nanotubos de Carbono , Purificação da Água , Quitosana/química , Membranas Artificiais , Nanofibras/química , Álcool de Polivinil/química , Povidona , Purificação da Água/métodos
17.
J Interferon Cytokine Res ; 42(5): 195-202, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35377243

RESUMO

Colorectal cancer (CRC) is one of the most common cancers in the world. Due to its preferential metastasis to the liver, CRC has become one of the leading causes of cancer-related deaths worldwide. There has evidence showing that a variety of subpopulations exist among cancer cells, which play an important role in liver metastasis. Growing evidence suggests that CD133 and C-X-C chemokine receptor type 4 (CXCR-4) are thought to contribute to cancer progression and metastasis. However, it has not been fully characterized in CRC. Here, we found that the expression of CD133 and CXCR4 in metastatic liver cancer tissues was higher than that of the primary tumor tissue and paratumor tissue. Furthermore, CD133+CXCR4+ cells were found to contribute to colorectal carcinogenesis and liver metastasis in vitro and in vivo. Moreover, CXCR4 blocked significantly inhibited the CD133+CXCR4+ cells metastatic to the liver in a mouse model. We also showed that CD133+CXCR4+ induced significant phosphorylation of PI3K/AKT. In conclusion, our data demonstrate that CD133+CXCR4+ cell subsets play an important role in the development and progression of colon cancer.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Antígeno AC133/imunologia , Animais , Neoplasias Hepáticas/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores CXCR4/metabolismo , Transdução de Sinais
18.
Int J Biol Macromol ; 182: 750-759, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33836190

RESUMO

Polysaccharide based beads with unique porous structure have gained considerable interests due to their specific adsorption behaviors and biodegradability. The purpose of this paper was to develop hollow cellulose/carbon nanotubes composite beads with aligned porous structure which have potential applications in fast adsorption field. The composite beads were fabricated by ice template and freeze-drying technology. Different characterizations have proved that the carbon nanotubes and magnetic nanoparticles have been incorporated into the cellulose beads. Higher concentration of carbon nanotubes and cellulose would result in a larger diameter of the composite beads. The composite beads can effectively adsorb the methylene blue (MB). The pseudo-second-order model and Langmuir isotherm were best fitted to the adsorption. The composite beads showed a fast adsorption behavior towards MB with a t1/2 of 1.07 min obtained from pseudo-second-order model. The maximum adsorption capacity was 285.71 mg g-1 at pH 7.0. The composite beads also showed good reusability and biodegradability. We anticipate that different polysaccharides based composite beads with aligned porous structure can be obtained through the similar methods and applied in adsorption fields.


Assuntos
Celulose/análogos & derivados , Azul de Metileno/química , Nanotubos de Carbono/química , Adsorção , Nanocompostos/química , Porosidade
19.
Dev Comp Immunol ; 114: 103810, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750398

RESUMO

White spot syndrome virus (WSSV) is highly virulent toward shrimp, and F1 ATP synthase ß subunit (ATPsyn-ß) has been suggested to be involved in WSSV infection. Therefore, in this study, interactions between Penaeus monodon ATPsyn-ß (PmATPsyn-ß) and WSSV structural proteins were characterized. Based on the results of yeast two-hybrid, co-immunoprecipitation, and protein pull-down assays, WSSV VP51B and VP150 were identified as being able to interact with PmATPsyn-ß. Membrane topology assay results indicated that VP51B and VP150 are envelope proteins with large portions exposed outside the WSSV virion. Cellular localization assay results demonstrated that VP51B and VP150 co-localize with PmATPsyn-ß on the membranes of transfected cells. Enzyme-linked immunosorbent assay (ELISA) and competitive ELISA results demonstrated that VP51B and VP150 bound to PmATPsyn-ß in a dose-dependent manner, which could be competitively inhibited by the addition of WSSV virions. In vivo neutralization assay results further showed that both recombinant VP51B and VP150 could delay mortality in shrimp challenged with WSSV.


Assuntos
Proteínas de Artrópodes/genética , Membrana Celular/metabolismo , Infecções por Vírus de DNA/imunologia , Penaeidae/imunologia , ATPases Translocadoras de Prótons/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/metabolismo , Testes de Neutralização , Subunidades Proteicas/genética , Transporte Proteico , ATPases Translocadoras de Prótons/metabolismo , Proteínas do Envelope Viral/metabolismo , Proteínas Estruturais Virais/metabolismo
20.
Ann Transl Med ; 8(9): 606, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32566632

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection remains a threat to global public health. As a hallmark of HBV infection, hepatitis B surface antigen (HBsAg) has been used to screen for HBV infection for decades, and quantitative assays are also being clinically rejuvenated to predict the disease outcome and monitor the antiviral response. Herein, we developed and evaluated a hook-effect-free homogeneous quantitative HBsAg assay based on the light-initiated chemiluminescence immunoassay (LICA). METHODS: A hook-effect-free LICA algorithm was established by measuring the relative light units (RLUs) of two time points during the immunoreaction. The precision was assessed using low- and high-level controls. Consecutive clinical serum samples were tested using the LICA and Abbott Architect assay; samples producing inconsistent results were retested using supplementary assays including the HBsAg neutralization, HBV DNA, and Roche Elecsys HBsAg assays for further confirmation. The consistency, sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated. For the quantitative results, the correlation was analyzed. The coverage of different genotypes and mutations by the LICA was evaluated. Moreover, serial on-treatment and follow-up samples from chronic hepatitis B patients were also measured using the two assays. RESULTS: The LICA had better within-run and within-laboratory precisions than the Architect assay. In total, 5,176 clinical samples were tested. The two assays showed a consistency of 99.63%. The LICA showed greater specificity (99.95% vs. 99.77%) and PPV (99.75% vs. 98.77%) than the Architect assay, whereas the Architect assay showed greater sensitivity (100.00% vs. 99.01%) and NPV (100.00% vs. 99.82%). The two assays displayed an excellent correlation independent of genotypes and mutations. The LICA hook-free algorithm recognized 100% of the underestimated results. Furthermore, similar HBsAg dynamics were demonstrated using the LICA and Architect HBsAg assay. CONCLUSIONS: The hook-free LICA provides a reliable tool for screening for HBV infection and quantifying HBsAg.

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