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The human immune system plays a pivotal role in protecting the body against pathogens, maintaining homeostasis, and preventing disease. Immunomodulation, the process of regulating immune responses, is crucial for optimal health. In recent years, there has been growing interest in natural remedies for immune system modulation, driven by the recognition of their potential efficacy and safety profiles. This project aims to investigate the immunomodulatory effects of drumstick leaves tablets, derived from Moringa oleifera, a plant known for its rich nutritional and medicinal properties. The study will explore the potential of drumstick leaves tablets to modulate immune responses through in vitro and in vivo experiments. Through comprehensive analysis of the immunomodulatory properties of drumstick leaves tablets, this project aims to contribute to our understanding of natural remedies for immune system modulation. The findings could have significant implications for the development of novel therapeutic interventions aimed at enhancing immune function and improving human health.
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Agentes de Imunomodulação , Moringa oleifera , Folhas de Planta , Comprimidos , Moringa oleifera/química , Folhas de Planta/química , Agentes de Imunomodulação/farmacologia , Animais , Fatores Imunológicos/farmacologia , Camundongos , Humanos , Medicamentos de Ervas Chinesas/farmacologiaRESUMO
Parvoviruses are ubiquitous pathogens that cause fatal disease in cats. Feline panleukopenia virus (FPV) is a primitive virus reported first and canine parvovirus (CPV) evolved from FPV and was reported later. Both induce disease in cats and dogs with correlative signs. FPV in domestic cats is genetically diverse and some strains may differ from those used for vaccination. In this study, a virus of FPV strain, ABT/MVC/2022/FPV/001, was identified from a fecal sample of the suspected cat with severe haemorrhagic gastroenteritis. The phylogenetic analysis and complete genome sequence of the strain share 99.75% nucleotide identity with FPV variant MH559110 belonging to Tamil Nadu, India. The results also reveal similarities to strains isolated from Italy, Belgium, and China. The deduced amino acid sequence of isolated strain revealed specific amino acid substitution (Pro5Ala, Phe6Val, His7Gln, Asn9Asp, Lys16Arg, Lys19Arg, Asn52Lys, Gly58Trp, Thr66Ser, Lys67Arg, Leu70His, Asn373Asp and Ala390Thr) which differed from MH559110 and other strains. The complete genomic analysis revealed that the FPV strain circulating in India is evolving rapidly with unique antigenic variations between field FPV, CPV and vaccine strains which may be the major cause for vaccine failure in vaccinated cats. Supplementary Information: The online version contains supplementary material available at 10.1007/s13337-023-00854-7.
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Technological advances have accelerated the pursuit of transparent conducting thin films (TCFs) with superior mechanical properties, durability, efficient optoelectrical performance and substrate compatibility as a pivotal focus in the realm of flexible transparent electronics. Against this background, this work investigates the fabrication of multilayer silver nanowire (AgNW) thin films reinforced by zinc tin oxide (ZTO) thin film encapsulation on polycarbonate substrates by a combination of sputtering and spin-coating techniques. An investigation of the influence of AgNW percolation networks on the optoelectrical properties of ZTO/AgNW/ZTO hybrid thin films was carried out. The impact of ZTO protective layers on the enhancement of electrical properties, adhesivity, flexibility and environmental stability of the multilayer TCF was elucidated. Additionally, to explore the compatibility of the fabricated TCF in integrated device and stealth applications, its electromagnetic interference shielding properties were investigated. The hybrid TCF showed 99.47% EMI shielding efficiency with an absorption-dominant EMI shielding effectiveness of 22.7 dB in the x-band region.
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AIM: The monocyte-to-high-density lipoprotein cholesterol ratio (MHR) has currently been proposed as an indicator of inflammation. The aim of the present study was to assess the relationship between the monocyte-to-high-density lipoprotein cholesterol ratio and periodontal health and disease. MATERIALS AND METHODS: A total of 90 patients were selected for the study - 30 healthy patients (group I) and 60 periodontitis patients (groups II and III). All the patients were subjected to blood sampling and serum malondialdehyde (MDA), high-density lipoprotein cholesterol (HDL) levels and monocyte counts were estimated. RESULTS: Monocyte-to-high-density lipoprotein cholesterol ratio was 80.64 ± 28.71 for patients with moderate periodontitis (group II), 95.14 ± 53.21 in severe periodontitis (group III), and 14.28 ± 16.05 for the healthy patients. Monocyte-to-high-density lipoprotein cholesterol ratio values were found to be statistically significantly higher than the control group (p < 0.001). Monocyte-to-high-density lipoprotein cholesterol ratio also showed significantly positive correlation with the severity of periodontitis. CONCLUSION: Malondialdehyde and MHR are increased in periodontal disease and correlate with severity of the periodontal disease. CLINICAL SIGNIFICANCE: Monocyte-to-high-density lipoprotein cholesterol ratio is a novel, readily available inflammatory and oxidative stress marker in patients with periodontitis and can be useful to evaluate periodontitis and disease severity.
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Monócitos , Doenças Periodontais , Humanos , HDL-Colesterol , Projetos Piloto , Biomarcadores , MalondialdeídoRESUMO
The present study examined 434 field samples including serum (n = 273), swabs from natural orifices (n = 52) and postmortem tissue samples (n = 109) from both suspected and asymptomatic swine from Andhra Pradesh, Karnataka, Kerala, Pondicherry, Tamil Nadu, and Telangana states in southern India. All the samples were processed for molecular screening of PCV3 by specific PCR assay. Overall molecular positivity rate of PCV3 was found to be 0.7% in southern India with one sample positive from each state of Tamil Nadu, Kerala and Telangana. All the three PCR positive PCV3 samples are detected from reproductive failures and were processed and propagated in PK15 cell line for virus isolation. Out of 3 samples processed, one (INDKL9PK76) PCV3 isolate could be obtained in this study and it was confirmed by specific PCR at third and fifth passage levels. Sequencing of PCV3 positive PCR amplicon (INDKL9PK76) revealed 1004 nucleotides and BLAST analysis confirmed partial sequence of the PCV3 genome. The aligned contig sequence was submitted to GenBank under the accession number of MW627201. PCV3 sequence in this study revealed 99% homology with PCV3 isolates from Europe and China. Phylogentic analysis of the PCV3 isolate-INDKL9PK76 sequence along with established PCV3 genotypes revealed clustering within PCV3 genotypes. Characterization of PCV3 (INDKL9PK76) isolate based on deduced amino acid composition of PCV3-capsid protein revealed "A" (alanine) and "R" (arginine) at 24th and 27th residues respectively confirming the incidence of PCV3a genotype. This study evidences PCV3 associated reproductive failure in domestic pigs for the first time in southern India.
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BACKGROUND: Porcine circovirus 2 is globally noted swine pathogen with multiple genotypes associated with vast clinical and subclinical outcomes. This study aimed to isolate and characterize PCV2 genotypes circulating in southern states of India. METHODS AND RESULTS: A total of 434 field samples comprising of serum (n = 273), tissues (n = 109) and swabs (n = 52) collected from swine during 2019 to 2021 from southern states of India were screened for PCV2 by specific polymerase chain reaction (PCR) assay. Molecular prevalence of PCV2 in southern India was found to be 12.21% (n = 53). All the 53 PCV2 positive samples were further subjected to the PCR assay with designed primers targeting full length amplification of ORF2 gene of PCV2 for molecular characterization. Randomly 32 positive samples by full length PCV2-ORF2 gene PCR were sequenced for genotyping. Signature motif and phylogenetic analysis of 32 PCV2 sequences revealed 62.5% (n = 20) prevalence of PCV2d genotype followed by 21.8% (n = 7) of PCV2h or PCV2-IM1 and 15.6% (n = 5) of PCV2b genotypes. Twenty five PCR positive field samples were subjected for virus isolation in PK15 cells and characterized. Out of 25 samples processed 5 (20%) PCV2 isolates obtained in this study were confirmed by PCR and immune fluorescence assay. Molecular characterization of PK15 adapted five PCV2 isolates confirmed circulation of PCV2d, PCV2h and PCV2b genotypes in pigs under field conditions in southern India. CONCLUSIONS: Isolation and molecular epidemiological study of PCV2 in southern states of India evidences high circulation of PCV2d genotypes in field conditions in comparison to other genotypes.
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Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Suínos , Animais , Circovirus/genética , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Filogenia , Doenças dos Suínos/epidemiologia , GenótipoRESUMO
Angiomyofibroblastoma (AMF) is a rare benign soft-tissue tumor that most frequently affects the lower genital tract of young to middle-aged women. It mainly consists of two components: stromal cells and prominent vasculature. Clinically, it is usually asymptomatic and resembles Bartholin's cyst. Although it is a benign tumor, cases with recurrence and sarcomatous transformation have been reported. Due to the overlapping of histopathological picture, diagnostic perplexity often arises between AMF and aggressive angiomyxoma (AAM). AMF being benign in nature is treated by local excision, whereas AAM is a more infiltrative lesion that has a higher tendency for local recurrence.
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Background: The energy-constrained heterogeneous nodes are the most challenging wireless sensor networks (WSNs) for developing energy-aware clustering schemes. Although various clustering approaches are proven to minimise energy consumption and delay and extend the network lifetime by selecting optimum cluster heads (CHs), it is still a crucial challenge. Methods: This article proposes a genetic algorithm-based energy-aware multi-hop clustering (GA-EMC) scheme for heterogeneous WSNs (HWSNs). In HWSNs, all the nodes have varying initial energy and typically have an energy consumption restriction. A genetic algorithm determines the optimal CHs and their positions in the network. The fitness of chromosomes is calculated in terms of distance, optimal CHs, and the node's residual energy. Multi-hop communication improves energy efficiency in HWSNs. The areas near the sink are deployed with more supernodes far away from the sink to solve the hot spot problem in WSNs near the sink node. Results: Simulation results proclaim that the GA-EMC scheme achieves a more extended network lifetime network stability and minimises delay than existing approaches in heterogeneous nature.
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This study used 56 aborted and stillborn fetuses from organized swine farms in Tamil Nadu and Kerala, southern states of India. All samples were screened by using a PCR assay that targets the NS1 gene for PPV. Furthermore, the PCR positive samples were subjected to amplification of the VP2 gene of PPV1 with designed primers and sequenced for further study. The PCR screening of 56 samples found that 14.3% (n = 8) were positive for PPV genome. According to VP2 gene-based PCR for PPV1, 897 bp specific amplicons were detected in all eight of the samples. Two of the eight positive samples (L17 and T5) were sequenced and annotated randomly. The BLAST analysis of contig sequence INDTNCHN-T5 revealed 100% sequence homology with Chinese PPV1genome, whereas sequence from INDTNCHN-L17 revealed 99.43% sequence homology with Spain, Chinese, and German. PPV1 sequences and both the sequences INDTNCHN-T5 and INDTNCHN-L17 were submitted to the GenBank under the accession numbers MW822566 and MW822567 respectively. A phylogenetic analysis of the sequences in this study revealed specific grouping along with PPV1 strains in cluster E. Amino acid analysis of both isolated sequences in addition to the reference sequence from PPV1 showed variations in position 215 (I to T) in both the isolates, variation at position 228 (Q to E) in T5 isolate and variations at position 59 (L to M) and 314 (K to E) in L17 isolate. This study represents the first report of PPV1 cluster E in Tamil Nadu, southern India.
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Parvovirus Suíno , Animais , DNA Viral/genética , Índia , Parvovirus Suíno/genética , Filogenia , Reação em Cadeia da Polimerase/veterinária , SuínosRESUMO
The amount of energy required by Cloud Data Centers (CDCs) has increased significantly in this digital age, and as a result, there is a pressing need to reduce CDC energy ingesting. Consolidation of virtual machines (VMs) and effective virtual machine placement (VMP) techniques are commonly employed in large data middles to reduce energy consumption. The VMP is an NP-hard subject with infeasible optimum explanations even for tiny data middles, and it is dealt with using the Metaheuristic Optimization Algorithm, which is an experiential approach to optimization. With this in mind, this study introduces a novel energy-aware VMP technique for CDCs that is founded on the Disordered Salp Swarm Optimization Algorithm (EAVMP-CSSA) and is enhanced for energy efficiency (EAVMP-CSSA). The EAVMP-CSSA technique attempts to reduce CDC energy ingesting by dropping the quantity of active servers supporting virtual machines. The recommended EAVMP-CSSA strategy also aims to balance the resource operation of active servers (i.e., CPU, RAM, and Bandwidth), hence reducing waste and increasing efficiency. Furthermore, by combining the ideas of chaotic maps with the standard Salp Swarm Optimization Algorithm (SSA), the CSSA is intended to improve overall performance and reduce computational costs (SSA). A comprehensive range of experimental analyses are performed to ensure that the EAVMP-CSSA technique performs better, and the findings are compared to current VMP techniques. The EAVMP-CSSA approach achieves an effective outcome with a maximum service rate of 98.12%, whereas the Random, FFD, ACO, and AP-ACO procedures achieve a minimum service rate of 74.40%, 78.80%, 90.70%, and 96.31%, respectively. The experimental results demonstrate that the EAVMP-CSSA approach outperforms other assessment metrics.
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Algoritmos , BenchmarkingRESUMO
Hamartoma presenting in the larynx is a rare entity. The common presentation of such a lesion may include stridor, hoarseness of voice, choking sensation, dyspnea and in children, failure to thrive. It is a benign lesion and can be confused with other benign lesions like lipoma, fibroma, chondromas etc. Pathologically it consists of a mesodermal compartment and a granular compartment. Hamartomas mainly occur in pediatric age group. When it occurs in adults, males are more commonly affected than females. With very few cases reported so far, we present a case of laryngeal hamartoma presenting in a lady with progressive hoarseness of voice as a presenting feature.
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This work aimed to identify the lead causes of upper limb injury presenting to a busy hand and major trauma unit during the UK COVID-19 domestic lockdown period, in comparison to a cohort from the same period one year previously. Hand and upper limb injuries presenting to the host organization during a pre-lockdown period (23rd March 2019-11th May 2019) and the formal UK lockdown period (23rd March 2020-11th May 2020) were compared, using data collated from the host institution's hand surgery database. The UK lockdown period was associated with a 52% fall in the number of patients presenting to the service with hand and upper limb injuries (589 pre-lockdown vs. 284 during lockdown). There was a significant increase in the proportion of injuries due to machinery use during lockdown (38, 6.5% pre-lockdown vs. 33, 11.6% during lockdown, P = 0.009), other etiologies were consistent. The proportion requiring surgical management were similar (n = 272, 46.2% pre-lockdown vs. n = 138, 48.6% during lockdown, P = 0.50). The proportion requiring overnight admission fell (n = 94, 16.0% pre-lockdown vs. 29, 10.2% during lockdown, P = 0.022). COVID-19 related lockdown in the UK resulted in a reduction in the presenting numbers of hand related injuries; however almost half of these patients still required surgery. These data may be of use to other hand surgery centers for resource planning during future lockdown periods, and for injury prevention strategies in the post-COVID-19 world.
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COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Traumatismos da Mão/epidemiologia , Traumatismos da Mão/etiologia , Extremidade Superior/lesões , Estudos de Coortes , Traumatismos da Mão/cirurgia , Humanos , Procedimentos Ortopédicos/estatística & dados numéricos , Pandemias , Admissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Reino Unido/epidemiologia , Extremidade Superior/cirurgiaRESUMO
In India, an estimated 50% of tuberculosis (TB) patients are diagnosed and managed by private providers (PPs). However, there is limited information on treatment outcomes among those treated by PPs largely because of a lack of systems for patient follow-up and documentation of the outcomes. Tuberculosis Health Action Learning Initiative (THALI) project implemented in six districts of West Bengal, supported PPs in managing TB patients and systematically documented the TB treatment outcomes of such patients. This provided us an opportunity to describe the treatment outcomes and assess factors associated with 'unsuccessful outcomes' among TB patients notified by PPs from January to April 2018. This was a retrospective cohort study using routinely collected data. During the study reference period, 2347 patients were notified from 389 PPs. The patient's mean (SD) age was 39.9 (17.2) years and 61% were males. Of the total, about 86% had pulmonary TB, 95% were new cases, and 23% were microbiologically confirmed (either on sputum smear microscopy or Xpert assay). Among 2347 patients, 19% received free drugs from the National Tuberculosis Program (NTP) under the supervision of PPs while the rest purchased anti-TB drugs from the private pharmacies. The 'successful outcomes' (cured and treatment completed) were seen in 86.1% (95% confidence interval (CI), 84.6%-87.4%) patients and 8.6% were 'not evaluated'. The patients who received free NTP drugs (adjusted relative risk-4.0 (95% CI: 3.1-5.0)) had a higher risk of 'unsuccessful outcomes' than those who availed of drugs from private pharmacies. The high 'successful outcomes' among TB patients treated by PPs are promising. However, higher 'unsuccessful outcomes' among patients on free NTP drugs need to be explored, and suitable corrective actions have to be taken.
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Tuberculose Pulmonar , Tuberculose , Adulto , Humanos , Índia/epidemiologia , Masculino , Setor Privado , Estudos Retrospectivos , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologiaRESUMO
Adequate vascularization of scaffolds is a prerequisite for successful repair and regeneration of lost and damaged tissues. It has been suggested that the maturity of engineered vascular capillaries, which is largely determined by the presence of functional perivascular mural cells (or pericytes), plays a vital role in maintaining vessel integrity during tissue repair and regeneration. Here, we investigated the role of pericyte-supported-engineered capillaries in regenerating bone in a critical-size rat calvarial defect model. Prior to implantation, human umbilical vein endothelial cells and human bone marrow stromal cells (hBMSCs) were cocultured in a collagen hydrogel to induce endothelial cell morphogenesis into microcapillaries and hBMSC differentiation into pericytes. Upon implantation into the calvarial bone defects (8 mm), the prevascularized hydrogels showed better bone formation than either untreated controls or defects treated with autologous bone grafts (positive control). Bone formation parameters such as bone volume, coverage area, and vascularity were significantly better in the prevascularized hydrogel group than in the autologous bone group. Our results demonstrate that tissue constructs engineered with pericyte-supported vascular capillaries may approximate the regenerative capacity of autologous bone, despite the absence of osteoinductive or vasculogenic growth factors.
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Células Imobilizadas , Hidrogéis , Células-Tronco Mesenquimais , Crânio , Animais , Células Imobilizadas/metabolismo , Células Imobilizadas/patologia , Células Imobilizadas/transplante , Xenoenxertos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Ratos , Ratos Nus , Crânio/irrigação sanguínea , Crânio/lesões , Crânio/metabolismo , Crânio/patologiaRESUMO
It has long been proposed that recapitulating the extracellular matrix (ECM) of native human tissues in the laboratory may enhance the regenerative capacity of engineered scaffoldsin-vivo. Organ- and tissue-derived decellularized ECM biomaterials have been widely used for tissue repair, especially due to their intrinsic biochemical cues that can facilitate repair and regeneration. The main purpose of this study was to synthesize a new photocrosslinkable human bone-derived ECM hydrogel for bioprinting of vascularized scaffolds. To that end, we demineralized and decellularized human bone fragments to obtain a bone matrix, which was further processed and functionalized with methacrylate groups to form a photocrosslinkable methacrylate bone ECM hydrogel- bone-derived biomaterial (BoneMA). The mechanical properties of BoneMA were tunable, with the elastic modulus increasing as a function of photocrosslinking time, while still retaining the nanoscale features of the polymer networks. The intrinsic cell-compatibility of the bone matrix ensured the synthesis of a highly cytocompatible hydrogel. The bioprinted BoneMA scaffolds supported vascularization of endothelial cells and within a day led to the formation of interconnected vascular networks. We propose that such a quick vascular network formation was due to the host of pro-angiogenic biomolecules present in the bone ECM matrix. Further, we also demonstrate the bioprintability of BoneMA in microdimensions as injectable ECM-based building blocks for microscale tissue engineering in a minimally invasive manner. We conclude that BoneMA may be a useful hydrogel system for tissue engineering and regenerative medicine.
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Bioimpressão , Bioimpressão/métodos , Células Endoteliais , Matriz Extracelular/química , Humanos , Hidrogéis/química , Engenharia Tecidual/métodos , Alicerces Teciduais/químicaRESUMO
Engineered tissue constructs require the fabrication of highly perfusable and mature vascular networks for effective repair and regeneration. In tissue engineering, stem cells are widely employed to create mature vascularized tissues in vitro. Pericytes are key to the maturity of these vascular networks, and therefore the ability of stem cells to differentiate into pericyte-like lineages should be understood. To date, there is limited information regarding the ability of stem cells from the different tissue sources to differentiate into pericytes and form microvascular capillaries in vitro. Therefore, here we tested the ability of the stem cells derived from bone marrow (BMSC), dental pulp (DPSC) and dental apical papilla (SCAP) to engineer pericyte-supported vascular capillaries when encapsulated along with human umbilical vein endothelial cells (HUVECs) in gelatin methacrylate (GelMA) hydrogel. Our results show that the pericyte differentiation capacity of BMSC was greater with high expression of α-SMA and NG2 positive cells. DPSC had α-SMA positive cells but showed very few NG2 positive cells. Further, SCAP cells were positive for α-SMA while they completely lacked NG2 positive cells. We found the pericyte differentiation ability of these stem cells to be different, and this significantly affected the vasculogenic ability and quality of the vessel networks. In summary, we conclude that, among stem cells from different craniofacial regions, BMSCs appear more suitable for engineering of mature vascularized networks than DPSCs or SCAPs.
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Capilares , Diferenciação Celular/fisiologia , Polpa Dentária/citologia , Hidrogéis , Pericitos/citologia , Células-Tronco/citologia , Engenharia Tecidual/métodos , Proliferação de Células/fisiologia , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/fisiologiaRESUMO
Titanium dioxide (TiO2) thin films were rapidly coated on Corning glass substrates from the precursor solution using the wire-bar technique at the room temperature and then post-annealed at 400, 500 and 600 °C for 1 h under atmospheric conditions. The structural, morphological, optical, wettability and photocatalytic properties of the films were studied. X-ray diffraction analysis confirmed the formation of an anatase TiO2 structure irrespective of the post-annealing temperatures. The optical transparency of the films in the visible range was measured to be > 70%. A water contact angle (WCA) of ~0° was observed for TiO2 thin-film, post-annealed at 400 °C and 500 °C. However, WCA of 40.3° was observed for post-annealed at 600 °C. The photocatalytic dye-degradation using post-annealed thin-film was investigated indicating a steady improvement in the dye-degradation percentage (from 24.3 to 29.4%) with the increase of post-annealing temperature. The demonstrated TiO2 thin-films deposited by wire-bar coating technique showed promises for the manufacturing of large-area cost-effective self-cleaning window glass.
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Corantes/química , Titânio/química , Catálise , Vidro/química , Fotoquímica/métodos , Soluções/química , Temperatura , Molhabilidade , Difração de Raios X/métodosRESUMO
We report the preparation and characterization of a new heterostructured Ag-TiO2/ZnFe2O4 (ATZ) nanocomposite. X-ray diffraction (XRD) reveals the presence of spinel type ZnFe2O4 and anatase TiO2. Scanning electron microscope (SEM) images of ATZ nanocomposites show that Ag nanoparticles are successfully loaded on the composite Ag-TiO2 and is uniformly distributed on surface of ZnFe2O4 forming a nanocomposite with an approximate particle size of 44.8 nm. High-resolution transmission electron microscope (HR-TEM) analysis clearly indicates the particles with spherical and hexagonal structure and sizes of most of the particles are below 50 nm. Ultra violet-visible diffuse reflectance spectra (UV-vis-DRS) show that Ag-TiO2/ZnFe2O4 has increased visible absorption than TiO2. Photoluminescence (PL) spectra shows that the intensity of ATZ is low relative to prepared TiO2. The photocatalytic degradation of Reactive Yellow 86 (RY 86) dye was studied. Based on the band gap energies of TiO2 and ZnFe2O4, a mechanism of degradation is given. Photocatalytic activity results suggest that as-prepared ATZ shows higher photodegradation efficiency than pure TiO2. The main reactive oxidative species involved in the degradation and stability of photocatalyst were also investigated. ATZ shows higher electrocatalytic activity than TiO2 for methanol electrooxidation. The cytotoxicity of ATZ was analysed. Multifunctionality of ATZ makes it useful for environmental and biomedical applications.
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Nanopartículas Metálicas , Nanocompostos , Catálise , Nanopartículas Metálicas/toxicidade , Prata , TitânioRESUMO
In the field of nanomedicine, drug-loaded nanocarriers that integrate nanotechnology and chemotherapeutics are widely used to achieve synergistic therapeutic effects. Here, we prepared mesoporous silica nanoparticles capped with cerium oxide nanoparticles (COP@MSN) wherein a pH trigger-responsive mechanism was used to control drug release and intracellular drug delivery. We blocked the mesopores of the carboxyl-functionalized MSN with aminated COP. These pores could be opened in acidic conditions to release the loaded drug, thus establishing a pH-responsive drug release system. We loaded doxorubicin (DOX) as anticancer biomolecule into the pores of MSN and capped with COP. The COP@DOX-MSN system showed a typical drug release profile in an acidic medium, which, however, was not observed in a neutral medium. In vitro studies using cancer cell line (HeLa) proved that the COP@DOX-MSN entered efficiently into HeLa cells and released DOX to the level sufficient for cytotoxicity. The cytotoxic effect of COP in cancer cells was facilitated by the pro-oxidant property of COPs, which considerably raised the reactive oxygen species (ROS) level, thereby leading to cellular apoptosis. The combination of DOX with COP (COP@DOX-MSN) showed even higher ROS level, demonstrating a cytotoxic synergism of drug and nanoparticle in terms of ROS generation. Collectively, the COP@DOX-MSN is considered useful for cancer treatment with the combined capacity of pH-controlled drug delivery, chemotherapeutics, and redox activity.