Background Widespread elimination of malaria requires an ultra-sensitive detection method that can detect low parasitaemia levels seen in asymptomatic carriers who act as reservoirs for further transmission of the disease, but is inexpensive and easy to deploy in the field in low income settings. It was hypothesized that a new method of malaria detection based on infrared spectroscopy, shown in the laboratory to have similar sensitivity to PCR based detection, could prove effective in detecting malaria in a field setting using cheap portable units with data management systems allowing them to be used by users inexpert in spectroscopy. This study was designed to determine whether the methodology developed in the laboratory could be translated to the field to diagnose the presence of Plasmodium in the blood of patients presenting at hospital with symptoms of malaria, as a precursor to trials testing the sensitivity of to detect asymptomatic carriers. Methods The field study tested 318 patients presenting with suspected malaria at four regional clinics in Thailand. Two portable infrared spectrometers were employed, operated from a laptop computer or a mobile telephone with in-built software that guided the user through the simple measurement steps. Diagnostic modelling and validation testing using linear and machine learning approaches was performed against the gold standard qPCR. Sample spectra from 318 patients were used for building calibration models (112 positive and 110 negative samples according to PCR testing) and independent validation testing (39 positive and 57 negatives samples by PCR). Results The machine learning classification (support vector machines; SVM) performed with 92% sensitivity (3 false negatives) and 97% specificity (2 false positives). The Area Under the Receiver Operation Curve (AUROC) for the SVM classification was 0.98. These results may be better than as stated as one of the spectroscopy false positives was infected by a Plasmodium species other than Plasmodium falciparum or Plasmodium vivax, not detected by the PCR primers employed. Conclusions In conclusion, it was demonstrated that ATR-FTIR spectroscopy could be used as an efficient and reliable malaria diagnostic tool and has the potential to be developed for use at point of care under tropical field conditions with spectra able to be analysed via a Cloud-based system, and the diagnostic results returned to the user’s mobile telephone or computer. The combination of accessibility to mass screening, high sensitivity and selectivity, low logistics requirements and portability, makes this new approach a potentially outstanding tool in the context of malaria elimination programmes. The next step in the experimental programme now underway is to reduce the sample requirements to fingerprick volumes.
Gold nanoparticles (GNPs) were conjugated with gallic acid (GA) at various concentrations between 30 and 150 µM and characterized using transmission electron microscopy (TEM) and UV-Vis spectroscopy (UV-VIS). The anticancer activities of the gallic acid-stabilized gold nanoparticles against well-differentiated (M213) and moderately differentiated (M214) adenocarcinomas were then determined using a neutral red assay. The GA mechanism of action was evaluated using Fourier transform infrared (FTIR) microspectroscopy. Distinctive features of the FTIR spectra between the control and GA-treated cells were confirmed by principal component analysis (PCA). The surface plasmon resonance spectra of the GNPs had a maximum absorption at 520 nm, whereas GNPs-GA shifted the maximum absorption values. In an in vitro study, the complexed GNPs-GA had an increased ability to inhibit the proliferation of cancer cells that was statistically significant (P<0.0001) in both M213 and M214 cells compared to GA alone, indicating that the anticancer activity of GA can be improved by conjugation with GNPs. Moreover, PCA revealed that exposure of the tested cells to GA resulted in significant changes in their cell membrane lipids and fatty acids, which may enhance the efficacy of this anticancer activity regarding apoptosis pathways.
Background/Aim: Cholangiocarcinoma (CCA) is a stem cell-based cancer. The in vivo tumor microenvironment is not present in two-dimensional (2D) cultures, which is one of the limitations in cancer stem cell (CSC) research. Thus, we aimed to establish three-dimensional (3D) culture mimicking extracellular matrix (ECM) that could serve as a niche for CSC enrichment in CCA. Materials and Methods: Silk fibroin-gelatin/hyaluronic acid/heparan sulfate (SF-GHHs) scaffolds were fabricated by lyophilization in various ratios and compared to silk fibroin (SF) scaffold. The physical and biological characteristics of the scaffolds were investigated. Results: The SF-GHHs 1:2 scaffold with pore size of 350±102 μm harbored optimal porosity, good water uptake, and stable beta-sheet that supported the increase in KKU-213A cell proliferation and aggregation. The CSC and the epithelial-mesenchymal transition (EMT) markers were significantly upregulated in this scaffold compared to 2D. Moreover, drug sensitivity against cisplatin and gemcitabine in 3D culture was significantly higher than that in 2D culture. Conclusion:The SF-GHHs 1:2 scaffold could simulate ECM that may serve as a CSC niche of CCA, and reinforce stemness and EMT properties, suggesting its suitability for 3D CCA model, which supports CSC and new targeting drug research in CCA.Cholangiocarcinoma (CCA) is an aggressive cancer that arises from the epithelium of bile ducts with the highest incidence in Northeastern Thailand where liver flukes are endemic (1). The only curative treatment is surgery but is not effective in patients with late-stage cancer (2). Many lines of evidence indicated the implication of cancer stem cells (CSCs) in CCA (3-9). CSCs are a tumor cell subpopulation that is capable of self-renewal and differentiation. CSCs are related to cancer initiation, progression, and resistance to chemo-and radio-therapies (9). Although the traditional twodimensional (2D) culture has long been used in cancer research, it cannot mimic tumor microenvironment, which plays crucial roles in cell-cell and cell-matrix interactions giving rise to the differences in cancer morphology, proliferation, invasion, metastasis, signaling pathways and other biological functions when compared to in vivo conditions (10,11). Three-dimensional (3D) cell culture was established to mimic tumor-like in vivo conditions providing more predictive data for in vivo tests of CSCs in cancer research (12). There are two main types of 3D cancer models for CSC enrichment including scaffold-free and scaffoldbased methods (12).Most 3D CCA models are scaffold-free methods and organoid models (13,14). However, the tumor microenvironment is not represented in scaffold-free applications, whereas organoid generation is difficult, expensive, and time-consuming ( 14). The 3D porous scaffold 1155
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