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ABSTRACT COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. This virus's spread is mainly through droplets released from the nose or mouth of an infected person. Although vaccines have been developed that effectively reduce the effects that this viral infection causes, the most effective method to contain the virus's spread is numerous tests to detect and isolate possible carriers. However, the response time, combined with the cost of actual tests, makes this option impractical. Herein, we compare some machine learning methodologies to propose a reliable strategy to detect people positive to COVID-19, analyzing saliva spectra obtained by Fourier transform infrared (FTIR) spectroscopy. After analyzing 1275 spectra, with 7 strategies commonly used in machine learning, we concluded that a multivariate linear regression model (MLMR) turns out to be the best option to identify possible infected persons. According to our results, the displacement observed in the region of the amide I of the spectrum, is fundamental and reliable to establish a border from the change in slope that causes this displacement that allows us to characterize the carriers of the virus. Being more agile and cheaper than reverse transcriptase polymerase chain reaction (RT-PCR), it could be reliably applied as a preliminary strategy to RT-PCR.
RESUMEN La COVID-19 es una enfermedad infecciosa ocasionada por el virus SARS-CoV-2. La propagación de este virus se produce principalmente a través de gotitas liberadas por la nariz o la boca de una persona infectada. Aunque se han desarrollado vacunas que permiten reducir efectivamente los efectos que esta infección viral provoca, el método más eficaz para contener la propagación del virus son las numerosas pruebas para detectar y aislar los posibles portadores. Sin embargo, el tiempo de respuesta, combinado con el costo de las pruebas reales, hace que esta opción sea poco práctica. Aquí, comparamos algunas metodologías de machine learning para proponer una estrategia confiable para detectar personas positivas a COVID-19 analizando espectros de saliva obtenidos por espectroscopia infrarroja transformada de Fourier (FTIR). Tras analizar 1275 espectros, con 7 estrategias comúnmente empleadas en el área de machine learning, concluimos que un modelo de regresión lineal multivariante (MLMR) resulta ser la mejor opción para identificar posibles infectados. De acuerdo con nuestros resultados, el desplazamiento observado en la región de la amida I del espectro, resulta fundamental y confiable para establecer una frontera a partir del cambio de pendiente que este provoca. Al ser más ágil y económica que la reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR), podría aplicarse confiablemente como estrategia preliminar a RT-PCR.
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This study aimed to investigate the enhancing effect of muscone on the transdermal penetration of traditional Chinese medicine ingredients and explore its possible mechanism of action. The Franz diffusion cells were employed to investigate the effect of muscone on the transdermal permeation of a series of model drugs with a wide range of log P values. The solubilities at saturation and the stratum corneum(SC)/vehicle partition coefficients of model drugs were measured to evaluate the effect of muscone on drug thermodynamic activities and partition of drugs into SC. Attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR) was employed to explore the effect of muscone on the molecular structure of SC. The results showed that muscone significantly promoted the transdermal penetration of hydrophilic and lipophilic drugs, and the enhancement ratio(ER) increased with the decrease in the log P. Muscone could interact with the SC lipids to increase the disorder and fluidity of lipid bilayer packing, which improved skin permeability and promoted transdermal absorption of drugs. This study provides a scientific basis for the application of muscone in traditional Chinese medicine topical preparations.
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Animals , Rats , Administration, Cutaneous , Cycloparaffins , Medicine, Chinese Traditional , Permeability , Rats, Sprague-Dawley , Skin/metabolism , Skin AbsorptionABSTRACT
@#Introduction: Accelerants and fabrics are commonly used to spread fire attributable to their highly flammable properties. Hence, having the ability to discriminate the different types of accelerants on various types of fabrics after fire and/or arson using the non-destructive Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy coupled with chemometric techniques appears forensically relevant. Methods: Six types of fabrics viz. cotton, wool, silk, rayon, satin, and polyester, were burnt completely with RON95 and RON97 gasoline as well as diesel. Subsequently, the samples were analyzed by ATR-FTIR spectroscopy followed by Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) for discriminating the different types of accelerants on such burned fabrics. Results: RON95 showed the fastest rate of burning on all fabric types. Results also revealed that while wool had the slowest burning rate for all the three different accelerants, polyester, cotton, and satin demonstrated the highest rate of burning in RON95, RON97, and diesel, respectively. FTIR spectra revealed the presence of alkane, alcohol, alkene, alkyne, aromatic, and amine compounds for all fabrics. The two dimensional PCA (PC1 versus PC2) demonstrated 71% of variance and it was improved by cross-validation through the three dimensional LDA technique with correct classification of 77.8%. Conclusion: ATR-FTIR spectroscopy coupled with chemometric techniques had enabled identification of the functional groups, as well as statistically supported discrimination of the different accelerants, a matter of relevance in forensic fire and arson investigations.
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@#Introduction: Non-destructive analysis of biological evidence has been paramount importance in the forensic investigation since it is an effective tool in establishing a standard that could be employed to differentiate ensuing destructive tests of bio-fluids upon sample division between the plaintiff and defendant. Species identification of bloodstain found at the crime scene is very crucial in routine forensic work as this can assist the initial investigation by incorporating or excluding stain that is not human and to identify its origin if animal blood is involved. Methods: In this research, identification and discrimination of various blood species collected from seven domestic animals namely chicken, cow, deer, duck, fish, goat, and pig were investigated using non-destructive analytical techniques; ATRFTIR and visible spectroscopy coupled with principal component analysis and linear discriminant analysis (PCALDA) for classification purposes. Results: ATR-FTIR FTIR spectroscopic study demonstrated a higher rate of successful classification (≥ 90%) as compared to visible spectroscopic technique. Conclusion: ATR-FTIR spectroscopy has been an ideal, robust, and suitable tool for determining the blood species of domestic animals. The predictive model from PCA-LDA analysis can be utilised to produce higher classification rate for species determination from blood traces.
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Animals , Dogs , Cause of Death , Diagnosis , Erythrocyte Count , Fourier Analysis , Incidence , Least-Squares Analysis , Leukocyte Count , Mass Screening , Methods , Principal Component AnalysisABSTRACT
This study aimed to investigate the transdermal enhancing effect of essential oil from Zanthoxylum bungeanum(Z. bungeanum oil) in microemulsion gel(ZO-ME-gel) on permeation of different components,and reveal the transdermal enhancing mechanism of ZO-ME-gel. A series of components with different log P values were selected as model drugs and encapsulated in ZO-ME-gel to simplify and characterize the complex components of traditional Chinese medicine. The transdermal behavior of the model drugs was further examined using the improved Franz diffusion cell method. Then attenuated total reflection Fourier transform infrared spectroscopy(ATR-FTIR),differential scanning calorimetry(DSC) studies and hematoxylin-eosin(HE) staining were used to investigate the effects of Z. bungeanum oil and ZO-ME-gel on keratin,intercellular lipids and microstructure of the stratum corneum(SC). The results showed that Z. bungeanum oil and ZO-ME-gel had a good transdermal enhancing effect on both hydrophilic and lipophilic drugs,and the best effect was achieved when log P value was-0. 5. The transdermal enhancing mechanism of Z. bungeanum oil and ZO-ME-gel was related to affecting the order of the SC lipids,changing lipid fluidity and protein conformation,and disrupting the integrity of the SC structure. 5% Z. bungeanum oil had greater transdermal enhancing effect and destruction of SC structure than ZO-ME-gel. These results suggested that Z. bungeanum oil loaded in microemulsion gel still had a good transdermal enhancing effect although the effect was not as great as Z. bungeanum oil itself,in addition,ZO-ME-gel was less irritating to the skin and safer to use,which had a guiding role in the development and clinical application of Z. bungeanum oil-containing traditional Chinese medicine topical preparations.
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Administration, Cutaneous , Oils, Volatile , Skin , Skin Absorption , ZanthoxylumABSTRACT
Abstract Lonicera japonica Thunb., Caprifoliaceae, has been employed in traditional Chinese medicine for thousands of years. However, it is frequently confused with closely related species, and thus, a mixture of these species is commonly used. The sources of Lonicera species must be accurately and rapidly determined to ensure the clinical efficacy of herbal medicines. Attenuated total reflectance Fourier transform infrared spectroscopy and high-performance liquid chromatography with a diode array detector, combined with chemometrics methods, were used to comprehensively evaluate the Lonicera quality. The infrared fingerprint results indicated that the spectra of L. japonica and its related species were very similar in the range 4000-1800 cm-1, however a large number of chemical absorption peaks were observed in the region 1800-600 cm-1 with certain differences. The five Lonicera species had high chlorogenic acid (25.85-67.75 µg/mg), 3,5-di-O-caffeoylquinic acid (11.63-62.58 µg/mg), and 4,5-di-O-caffeoylquinic acid (2.64-30.91 µg/mg) contents. The chemical fingerprints of L. hypoglauca Miq. and L. confusa DC were the most similar to that of L. japonica Thunb. The chemical fingerprints of L. fulvotomentosa P.S. Hsu & S.C. Cheng and L. macranthoides Hands.-Mazz. were very different from that of L. japonica. A loading analysis indicated that the differences in the chemical fingerprints of the Lonicera species were mainly due to variations in the contents of the organic acids and flavonoids. Soft independent modeling of class analogy model was successfully developed to classify unknown samples of the five Lonicera species. This comprehensive, unbiased strategy provides adequate, reliable scientific evidence for authenticating herbal sources, therefore offering a powerful, new route for herbal analysis.
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Abstract Introduction Tendinopathy, a disease involving tendon inflammation and damage, results in considerable productivity and economic losses for the patient and the society. Currently available diagnosis/ treatment monitoring modalities are less efficacious and highly subjective, underlying the need for better tools. Previously, we have shown that Fourier Transform Infrared (FTIR) spectroscopy has potential in tendinopathy diagnosis/ monitoring, when combined with multivariate statistical analysis. The current study explores the spectral range that gave the best results in statistical analysis, to discover protein secondary structures associated with tendon injury and recovery that can act as markers of disease. Methods Animals (n=60) underwent a surgery in which Achilles tendon were injured by dropping a 20g weight. Rats were divided into three groups (n=20) - control (C), Achilles tendon injury (I) and Achilles tendon injury treated with amniotic membrane fragment treated (T). FTIR spectra were obtained from each group 3, 7, 14, and 28 days post injury/ treatment. Results Triple helix, β-turn, and disordered structure levels differ between control, injured and treated tendons over the time period studied. Parallel β-sheets increase steadily over time in treated tendons compared to control and injured. Conclusion Combined analysis of Triple helix, β- sheets, β-turn, and disordered structure levels may be useful for tendinopathy diagnosis and treatment monitoring. However, further studies in this area are required to confirm the findings.
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Abstract Marantodes pumilum (Blume) Kuntze (synonym: Labisia pumila (Blume) Fern.-Vill), Primulaceae, is well known for its traditional use as a post-partum medication among women in Malaysia. Three varieties of M. pumilum, var. alata Scheff., var. pumila and var. lanceolata (Scheff.) Mez. are commonly used. Nowadays, M. pumilum powder or extracts are commercially available as herbal supplements and beverages. Authentication of the variety is an important component of product quality control. Thus, the present work was aimed to compare the three varieties using microscopic, spectroscopic and chromatographic techniques. Microscopic anatomical examination and powder microscopy were performed on fresh and dried plant materials, respectively. Fingerprint profiles of the varieties were obtained using attenuated total reflectance-Fourier transform infrared spectrophotometer, high performance thin layer chromatography and high performance liquid chromatography. The microscopic examination showed presence of anisocytic stomata, scale and capitate glandular trichome in all varieties. The type of stomata and trichomes, outline structure of stem and leaf margin, petiole and midrib, organization of vascular system, areolar venation, pattern of anticlinal walls, the distribution of secretory canals and cell inclusion as well as the measurement of selected structures could be used to distinguish and identify each variety of M. pumilum. In addition, spectroscopic and chromatographic fingerprint analyses of the three varieties exhibited distinguishable profiles based on the intensity of certain peaks or bands. The findings from this study will provide systematic identification for these varieties.
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Objective To detect the molecular characteristics of the serum samples of rats suffered from sudden unexpected death of acute myocardial ischemia (experimental group) and death caused by air embolism (control group) applied by ATR-FTIR, and to discuss the forensic signiifcance of identiifcation of causes of death by sudden unexpected death of acute myocardial ischemia by two-dimension infrared spectroscopy. Methods Adult male SD rats were randomly divided into SCD group and DCAE group. The serum samples were analyzed by ATR-FTIR. The similarity coefifcient of spectra between two groups was analyzed by OMNIC software. The spectra with higher signal-noise ratio were obtained and used to build two-dimension spectra model by Matlab 2010a software. Results The peak shapes, positions and intensities of the spectra were extremely similar between two groups, and the similarity coefifcient reached 99.78%. Meanwhile, the similarity coefifcient of second derivative spectra decreased to 98.62% between two groups. Moreover, on the two-dimension spectra model, the component differences were present at about 1 625cm-1, 1 550cm-1, 1 080cm-1 and 860cm-1, and the number of auto-peaks was different, which suggested that the evident differences were related to the molecular contents of protein, glycogen, nuclear acid, and so on. Conclusion It is hard to differentiate the molecular differences of serum samples of rats between SCD and DACE based on one-dimension spectra. However, two-dimension infrared spectra could intuitively and effectively relfect the molecular differences, and it would apply to determining the cause of death in forensic science.