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1.
Anal Bioanal Chem ; 416(4): 993-1000, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38063906

RESUMEN

Precisely distinguishing between malignant and benign lung tumors is pivotal for suggesting therapeutic strategies and enhancing prognosis, yet this differentiation remains a daunting task. The growth rates, metastatic potentials, and prognoses of benign and malignant tumors differ significantly. Developing specialized treatment protocols tailored to various tumor types is essential for enhancing patient survival outcomes. Employing laser-induced breakdown spectroscopy (LIBS) in conjunction with a deep learning methodology, we attained a high-precision differential diagnosis of malignant and benign lung tumors. First, LIBS spectra of malignant tumors, benign tumors, and normal tissues were collected. The spectra were preprocessed and Z score normalized. Then, the intensities of the Mg II 279.6, Mg I 285.2, Ca II 393.4, Cu II 518.3, and Na I 589.6 nm lines were analyzed in the spectra of the three tissues. The analytical results show that the elemental lines have different contents in the three tissues and can be used as a basis for distinguishing between the three tissues. Finally, the RF-1D ResNet model was constructed by combining the feature importance assessment method of random forest (RF) and one-dimensional residual network (1D ResNet). The classification accuracy, precision, sensitivity, and specificity of the RF-1D ResNet model were 91.1%, 91.6%, 91.3%, and 91.3%, respectively. And the model demonstrates superior performance with an area under the curve (AUC) value of 0.99. The above results show that combining LIBS with deep learning is an effective way to diagnose malignant and benign tumors.


Asunto(s)
Aprendizaje Profundo , Neoplasias Pulmonares , Humanos , Análisis Espectral/métodos , Neoplasias Pulmonares/diagnóstico , Rayos Láser
2.
Prenat Diagn ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840299

RESUMEN

OBJECTIVE: To present the prenatal sonographic features and genomic spectrum of pregnancies with fetal Bardet-Biedl syndrome (BBS). METHODS: This was a retrospective study of 11 cases with BBS diagnosed by prenatal ultrasound and confirmed by genetic testing. Clinical and laboratory data were collected and reviewed for these cases, including maternal demographics, prenatal sonographic findings, molecular testing sequencing results, and pregnancy outcomes. RESULTS: All cases had unremarkable first-trimester ultrasound scans without reporting limb malformations. All had second-trimester abnormal ultrasounds: postaxial polydactyly in nine cases (9/11), renal abnormalities in seven (7/11), reduced amniotic fluid volume in two (2/11), central nervous system anomalies in two (2/11), and ascites in three (3/11). Ten fetuses presented with at least two-system anomalies, and one (Case 11) presented with only postaxial polydactyly. Variants were detected in five genes, including BBS2, ARL6/BBS3, BBS7, CEP290/BBS14 and IFT74/BBS22. Ten pregnancies were terminated in the second trimester, while one continued to term. CONCLUSION: Enlarged hyperechogenic kidneys and postaxial polydactyly are the two most common sonographic features of fetal BBS. Prenatal diagnosis of BBS can be done with ultrasound and genetic testing although the diagnosis may be made in the second trimester.

3.
Ann Hum Genet ; 87(6): 316-325, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37771257

RESUMEN

BACKGROUND: To evaluate the value of the real-time PCR-based multicolor melting curve analysis (MMCA) with an automatic analysis system used in a mass thalassemia screening and prenatal diagnosis program. METHODS: A total of 18,912 peripheral blood samples from 9456 couples and 1150 prenatal samples were detected by MMCA assay. All prenatal samples were also tested by a conventional method. Samples with unknown melting peaks, unusual peak height ratios between a wild allele and a mutant allele, or a discordant phenotype-genotype match were further studied by using multiplex ligation-dependent probe amplification (MLPA) or Sanger sequencing. All MMCA results were automatically analyzed and manually checked. The consistency between MMCA assay and conventional methods among prenatal samples was investigated. RESULTS: Except for initiation codon (T > G) (HBB:c.2T > G), all genotypes of thalassemia inside the scope of conventional methods were detected by MMCA assay. Additionally, 27 carriers with 10 rare HBB variants, 13 with α fusion gene, 1 with a rare deletion in α globin gene, and 1 with rare HBA variant were detected by using MMCA assay. CONCLUSION: MMCA can be an alternative approach used in routine thalassemia carrier screening and prenatal diagnosis for its high throughput, sufficient stability, low cost, and easy operation.


Asunto(s)
Talasemia alfa , Talasemia beta , Embarazo , Femenino , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Talasemia alfa/diagnóstico , Talasemia alfa/genética , Diagnóstico Prenatal/métodos , Genotipo , Talasemia beta/diagnóstico , Talasemia beta/genética , Mutación
4.
Prenat Diagn ; 43(13): 1662-1665, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37936555

RESUMEN

Noonan syndrome (NS) is a common clinical variable disease characterized by a number of features, mainly including congenital heart defects, short stature, and a variable degree of developmental delay. This disorder is transmitted mostly in an autosomal dominant manner and is genetically heterogeneous. We report three prenatal cases of LZTR1-related recessive NS. One case had a recurrent cystic hygroma at 13 weeks gestation and the pregnancy was terminated. Two cases had an increased nuchal translucency at 12 weeks' gestation, but a normal second trimester ultrasound; both presented with hypertrophic cardiomyopathy in the third trimester. The two infants were diagnosed with NS after birth. All of the three cases had invasive genetic investigations during pregnancy, and trio exome sequencing revealed biallelic likely pathogenic or pathogenic LZTR1 variants in the fetuses. All parents were LZTR1 variant carriers. Our report further strengthens the association of LZTR1 with an autosomal recessive form of NS. The affected fetuses are more likely to have cardiac anomalies. Clarification of molecular diagnosis has important implications in these families because they carry a 25% recurrence risk.


Asunto(s)
Cardiopatías Congénitas , Síndrome de Noonan , Lactante , Embarazo , Femenino , Humanos , Síndrome de Noonan/diagnóstico por imagen , Síndrome de Noonan/genética , Medida de Translucencia Nucal , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/genética , Diagnóstico Prenatal , Ultrasonografía Prenatal , Factores de Transcripción/genética
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(8): 1021-1027, 2023 Aug 10.
Artículo en Zh | MEDLINE | ID: mdl-37532505

RESUMEN

OBJECTIVE: To investigate the clinical features and genetic etiology of a case of Turner syndrome (TS) with rapidly progressive puberty. METHODS: A child who had presented at the Pediatric Endocrinology Clinic of the Shenzhen People's Hospital on January 19, 2022 was selected as the study subject. Clinical data of the child were collected. Peripheral blood sample of the child was subjected to chromosomal microarray analysis (CMA) and multiple ligation-dependent probe amplification (MLPA). Previous studies related to TS with rapidly progressive puberty were retrieved from the CNKI, Wanfang Data Knowledge Service Platform, Boku, CBMdisc and PubMed databases with Turner syndrome and rapidly progressive puberty as the keywords. The duration for literature retrieval was set from November 9, 2021 to May 31, 2022. The clinical characteristics and karyotypes of the children were summarized. RESULTS: The child was a 13-year-and-2-month-old female. She was found to have breast development at 9, short stature at 10, and menarche at 11. At 13, she was found to have a 46,X,i(X)(q10) karyotype. At the time of admission, she had a height of 143.5 cm (< P3), with 6 ~ 8 nevi over her face and right clavicle. She also had bilateral simian creases but no saddle nasal bridge, neck webbing, cubitus valgus, shield chest or widened breast distance. She had menstruated for over 2 years, and her bone age has reached 15.6 years. CMA revealed that she had a 58.06 Mb deletion in the Xp22.33p11.1 region and a 94.49 Mb duplication in the Xp11.1q28 region. MLPA has confirmed monosomy Xp and trisomy Xq. A total of 13 reports were retrieved from the CNKI, Wanfang Data Knowledge Service Platform, Boku, CBMdisc and PubMed databases, which had included 14 similar cases. Analysis of the 15 children suggested that their main clinical manifestations have included short stature and growth retardation, and their chromosomal karyotypes were mainly mosaicisms. CONCLUSION: The main clinical manifestations of TS with rapidly progressive puberty are short stature and growth retardation. Deletion in the Xp22.33p11.1 and duplication in the Xp11.1q28 probably underlay the TS with rapid progression in this child, which has provided a reference for clinical diagnosis and genetic counselling for her.


Asunto(s)
Pubertad , Síndrome de Turner , Humanos , Femenino , Adolescente , Síndrome de Turner/genética , Cromosomas Humanos X , Cariotipificación
6.
Hum Brain Mapp ; 43(11): 3498-3507, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426973

RESUMEN

Hierarchy is a fundamental organizational principle of the human brain network. Whether and how the network hierarchy changes in Alzheimer's disease (AD) remains unclear. To explore brain network hierarchy alterations in AD and their clinical relevance. Forty-nine healthy controls (HCs), 49 patients with mild cognitive impairment (MCI), and 49 patients with AD were included. The brain network hierarchy of each group was depicted by connectome gradient analyses. We assessed the network hierarchy changes by comparing the gradient values in each network across the AD, MCI, and HC groups. Whole-brain voxel-level gradient values were compared across the AD, MCI, and HC groups to identify abnormal brain regions. Finally, we examined the relationships between altered gradient values and clinical features. In the secondary gradient, the posterior default mode network (DMN) gradient values decreased significantly in patients with AD compared with HCs. Regionally, compared with HCs, both MCI and AD groups showed that most of the brain regions with increased gradient values were located in anterior DMN, while most of the brain regions with decreased gradient values were located in posterior DMN. The decrease of gradients in the left middle occipital gyrus was associated with better logical memory performance. The increase of gradients in the right middle frontal gyrus was associated with lower rates of dementia. The network hierarchy changed characteristically in patients with AD and was closely related to memory function and disease severity. These results provide a novel view for further understanding the underlying neuro-mechanisms of AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Conectoma , Encéfalo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Disfunción Cognitiva/patología , Humanos , Imagen por Resonancia Magnética/métodos , Red Nerviosa
7.
Prenat Diagn ; 42(12): 1488-1492, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35801292

RESUMEN

OBJECTIVE: To present both our center's and previously reported experience of prenatal diagnosis of Coffin-Siris syndrome (CSS) with regard to the laboratory testing and fetal features of this syndrome. METHODS: This was a retrospective study of eight pregnancies with fetal CSS identified by prenatal or postnatal genetic testing. Clinical and laboratory data were collected and reviewed for these cases, including maternal demographics, prenatal sonographic findings, chromosomal microarray and exome sequencing (ES) results, and pregnancy outcomes. RESULTS: A total of eight cases of fetal CSS based on molecular testing were detected. Two cases presented with an increased nuchal translucency (NT) in the first trimester. The remaining six were identified at the second trimester scan. Agenesis of the corpus callosum (ACC) was the most common sonographic finding, accounting for 5/7 (71.4%) cases in which a second trimester sonogram was performed: four had ACC as an isolated finding, and one had additional features of cerebellar hypoplasia and left congenital diaphragmatic hernia. CONCLUSION: CSS should be included in the differential diagnosis when ACC is found by prenatal ultrasound. Both chromosomal microarray and ES should be options when counseling patients with a structurally anomalous fetus.


Asunto(s)
Anomalías Múltiples , Hernias Diafragmáticas Congénitas , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Diagnóstico Prenatal/métodos , Anomalías Múltiples/diagnóstico por imagen , Anomalías Múltiples/genética , Ultrasonografía Prenatal/métodos , Primer Trimestre del Embarazo , Feto/diagnóstico por imagen , Agenesia del Cuerpo Calloso/diagnóstico por imagen , Agenesia del Cuerpo Calloso/genética , Medida de Translucencia Nucal/métodos
8.
Prenat Diagn ; 42(13): 1622-1626, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36326072

RESUMEN

OBJECTIVE: To examine the diagnostic yield of exome sequencing (ES) in singleton pregnancies with isolated fetal clubfoot. METHODS: Clinical data from singleton pregnancies with a sonographic diagnosis of isolated clubfoot and ES results between 2018 and 2021 were retrospectively obtained from a single referral medical center. The recorded data include maternal age, gestational age at sonographic diagnosis, the indication for genetic testing, ES results, and pregnancy outcomes. RESULTS: During the study period, 38 fetuses were prenatally diagnosed with isolated clubfoot by ultrasound and underwent ES after the copy number variant analysis was non-diagnostic. Through the trio-ES analysis, pathogenic or likely pathogenic variants were detected in 4 of 38 (10.5%) with the following genes: BRPF1, ANKRD17, FLNA, and KIF1A. All are de novo with three of autosomal dominant inheritance and one of X-linked recessive inheritance. CONCLUSION: Sonographic diagnosis of clubfoot, even isolated, increases the risk for monogenic syndromes. Exome sequencing should be an option for genetic investigation for such pregnancies.


Asunto(s)
Pie Equinovaro , Embarazo , Femenino , Humanos , Secuenciación del Exoma , Pie Equinovaro/diagnóstico por imagen , Pie Equinovaro/genética , Ultrasonografía Prenatal , Estudios Retrospectivos , Feto/diagnóstico por imagen , Diagnóstico Prenatal/métodos , Proteínas de Unión al ADN , Proteínas Adaptadoras Transductoras de Señales , Proteínas de Unión al ARN , Cinesinas
9.
Hemoglobin ; 46(4): 253-255, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35686459

RESUMEN

We report a de novo frameshift mutation in exon 3 of the ß-globin gene that leads to a ß-thalassemia (ß-thal) intermedia (ß-TI) phenotype in a 6-year-old Chinese boy. This novel mutation with deletion of the last nucleotide (-T) at codon 130 results in a ß-globin chain that is extended to 156 amino acid residues. This study highlights the importance of considering dominantly inherited ß-thal in the investigation of anemia, even in patients with ethnic backgrounds not usually associated with ß-thal and hematologically normal parents.


Asunto(s)
Globinas beta , Talasemia beta , Humanos , Globinas beta/genética , Globinas beta/química , Talasemia beta/diagnóstico , Talasemia beta/genética , Nucleótidos , Exones , Codón , Mutación
10.
Molecules ; 27(15)2022 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35897888

RESUMEN

The metabolomics approach has proved to be promising in achieving non-targeted screening for those unknown and unexpected (U&U) contaminants in foods, but data analysis is often the bottleneck of the approach. In this study, a novel metabolomics analytical method via seeking marker compounds in 50 pharmaceutical and personal care products (PPCPs) as U&U contaminants spiked into lettuce and maize matrices was developed, based on ultrahigh-performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS) output results. Three concentration groups (20, 50 and 100 ng mL-1) to simulate the control and experimental groups applied in the traditional metabolomics analysis were designed to discover marker compounds, for which multivariate and univariate analysis were adopted. In multivariate analysis, each concentration group showed obvious separation from other two groups in principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) plots, providing the possibility to discern marker compounds among groups. Parameters including S-plot, permutation test and variable importance in projection (VIP) in OPLS-DA were used for screening and identification of marker compounds, which further underwent pairwise t-test and fold change judgement for univariate analysis. The results indicate that marker compounds on behalf of 50 PPCPs were all discovered in two plant matrices, proving the excellent practicability of the metabolomics approach on non-targeted screening of various U&U PPCPs in plant-derived foods. The limits of detection (LODs) for 50 PPCPs were calculated to be 0.4~2.0 µg kg-1 and 0.3~2.1 µg kg-1 in lettuce and maize matrices, respectively.


Asunto(s)
Lactuca , Espectrometría de Masas en Tándem , Biomarcadores , Cromatografía Líquida de Alta Presión/métodos , Metabolómica/métodos , Análisis de Componente Principal , Zea mays
15.
Anal Chem ; 87(9): 4864-70, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25909601

RESUMEN

Metal-organic frameworks (MOFs) are microporous materials assembled from metal ions and organic linkers. Recently, many studies have been focused on the syntheses of MOFs with permanent porosity for various applications. However, no attention has been paid to controllable disassembly of MOFs and related applications. In this work, for the first time we synthesized novel tris(bipyridine)ruthenium(II)-functionalized MOFs (i.e., RuMOFs) that could be ion-responsively disassembled and release massive guest materials loaded in the frameworks. The synthesized RuMOFs exhibited much stability in aqueous solutions containing H(+), and many metal ions, but could be selectively and sensitively disassembled by Hg(2+) ions, resulting in the release of large quantities of Ru(bpy)3(2+). The target-responsive release mechanism was investigated and discussed in detail. On the basis of the ion-responsive disassembly and release, an ultrasensitive electrochemiluminescence sensing method for Hg(2+) has been developed with a very low limit of detection (5.3 × 10(-13) M). It was envisioned that the RuMOFs and similar target-responsive functional MOF materials would have promising applications in ultrasensitive and highly selective chemical sensing and even in accurately controllable drug delivering and releasing.


Asunto(s)
Mercurio/análisis , Mercurio/química , Compuestos Organometálicos/química , Iones/análisis , Factores de Tiempo
16.
Anal Chem ; 86(2): 1223-8, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24328057

RESUMEN

Novel highly fluorescent (FL) metal-organic frameworks (MOFs) have been synthesized by encapsulating branched poly-(ethylenimine)-capped carbon quantum dots (BPEI-CQDs) with a high FL quantum yield into the zeolitic imidazolate framework materials (ZIF-8). The as-synthesized FL-functionalized MOFs not only maintain an excellent FL activity and sensing selectivity derived from BPEI-CQDs but also can strongly and selectively accumulate target analytes due to the adsorption property of MOFs. The selective accumulation effect of MOFs can greatly amplify the sensing signal and specificity of the nanosized FL probe. The obtained BPEI-CQDs/ZIF-8 composites have been used to develop an ultrasensitive and highly selective sensor for Cu(2+) ion, with a wide response range (2-1000 nM) and a very low detection limit (80 pM), and have been successfully applied in the detection of Cu(2+) ions in environmental water samples. It is envisioned that various MOFs incorporated with FL nanostructures with high FL quantum yields and excellent selectivity would be designed and synthesized in similar ways and could be applied in sensing target analytes.


Asunto(s)
Carbono/química , Cobre/análisis , Colorantes Fluorescentes/química , Agua Dulce/química , Puntos Cuánticos/química , Contaminantes Químicos del Agua/análisis , Adsorción , Cationes Bivalentes , Límite de Detección , Microscopía Electrónica de Transmisión , Nanocompuestos/química , Nanocompuestos/ultraestructura , Polietileneimina/química , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Zeolitas/química
17.
Talanta ; 275: 126194, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38703481

RESUMEN

Lung cancer staging is crucial for personalized treatment and improved prognosis. We propose a novel bimodal diagnostic approach that integrates LIBS and Raman technologies into a single platform, enabling comprehensive tissue elemental and molecular analysis. This strategy identifies critical staging elements and molecular marker signatures of lung tumors. LIBS detects concentration patterns of elemental lines including Mg (I), Mg (II), Ca (I), Ca (II), Fe (I), and Cu (II). Concurrently, Raman spectroscopy identifies changes in molecular content, such as phenylalanine (1033 cm-1), tyrosine (1174 cm-1), tryptophan (1207 cm-1), amide III (1267 cm-1), and proteins (1126 cm-1 and 1447 cm-1), among others. The bimodal information is fused using a decision-level Bayesian fusion model, significantly enhancing the performance of the convolutional neural network architecture in classification algorithms, with an accuracy of 99.17 %, sensitivity of 99.17 %, and specificity of 99.88 %. This study provides a powerful new tool for the accurate staging and diagnosis of lung tumors.


Asunto(s)
Neoplasias Pulmonares , Espectrometría Raman , Espectrometría Raman/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Humanos , Rayos Láser , Teorema de Bayes , Estadificación de Neoplasias , Redes Neurales de la Computación
18.
Talanta ; 275: 126087, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38631267

RESUMEN

In the field of Laser Induced Breakdown Spectroscopy (LIBS) research, the screening and extraction of complex spectra play a crucial role in enhancing the accuracy of quantitative analysis. This paper introduces a novel approach for multiple screenings of LIBS spectra using Lorentz Screening and Sensitivity and Volatility Analysis. Initially, Create symmetrical sampling standards for Lorentz fitting. Then the Lorentz fitting is used to uniformly screen the collected spectral information on both sides in order to eliminate adjacent interference peaks. Subsequently, Sensitivity and Volatility Analysis is employed to further remove overlapping peaks and select spectra with low volatility and high sensitivity. Sensitivity and Volatility Analysis is a spectral discrimination method proposed on the premise of intensity's correlation with concentration. It utilizes a Z-score method that incorporates both deviation and standard deviation for effective analysis. Furthermore, it meticulously selects spectral lines with minimal interference and volatility, thereby augmenting the precision of quantitative analysis. The quantitative accuracy (R2) for Chromium (Cr) and Nickel (Ni) elements can reach 0.9919 and 0.9768, respectively. Their average errors can be reduced to 0.0566 % and 0.1024 %. The study demonstrates that Lorentz Screening and Sensitivity and Volatility Analysis can select high-quality characteristic spectral lines to improve the performance of the model.

19.
Front Aging Neurosci ; 16: 1330063, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650868

RESUMEN

Introduction: Tai Chi has proved to be an effective therapy for balance performance and cognition. However, non-consistency exists in the results of the effect of Tai Chi training on standing balance control in older adults. This study aimed to use traditional and non-traditional methods to investigate the effect of Tai Chi on standing balance in older adults. Methods: Thirty-six Tai Chi practitioners (TC group) and thirty-six older adults with no Tai Chi practice (control group) were recruited in this study. A Nintendo Wii Balance Board was used to record the center of pressure (COP) during standing balance over 20 s in the condition of eyes closed with three repetitions. The wavelet analysis, multiscale entropy, recurrence quantification analysis, and traditional methods were used to evaluate the standing balance control in the anterior-posterior (AP) and mediolateral (ML) directions. Results: (1) Greater sway mean velocity in the AP direction and sway Path length were found in the TC group compared with the control group; (2) lower Very-low frequency band (0.10-0.39 Hz) and higher Moderate frequency band (1.56-6.25 Hz) in the AP and ML directions were found in the TC group compared with the control group; (3) greater complexity index (CI) and lower determinism (DET) in the AP and ML directions were observed in the TC group compared with control group; (4) greater path length linked with smaller Very-low frequency band in the AP and ML directions and higher Moderate frequency band in the AP direction in both groups; (5) greater path length linked with lower DET and higher CI in the AP direction only in the TC group. Conclusion: Long-term Tai Chi practice improved sensory reweighting (more reliance on the proprioception system and less reliance on the vestibular system) and complexity of standing balance control in older adults. In addition, greater sway velocity may be as an exploratory role in standing balance control of TC older adults, which correlated with greater complexity, but no such significant relationship in the control group. Therefore, the effects of Tai Chi practice on standing balance control in older adults may be attributed to the improvement of sensory reweighting and complexity rather than reduced sway velocity or amplitude.

20.
Anal Methods ; 16(23): 3654-3662, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38757530

RESUMEN

The investigation of the mechanism underlying the impact of biological soft tissue sample preparation methods on laser-induced breakdown spectroscopy (LIBS) signals can enhance the stability of LIBS signals. Our study focused on four specific preparation methods applied to pork samples: rapid freezing, fresh slicing, drying, and pressing. The influence of various preparation techniques on the signal-to-noise ratio and fluctuation of Ca, Na, Mg, and CN bands within the sample spectra was assessed. The signal-to-noise ratios for samples that were dried and pressed notably improved. And the pressing method effectively mitigated the uneven distribution of pork tissue components, displaying superior spectral line stability. To explain this phenomenon, we used the Saha-Boltzmann diagram to estimate the plasma temperature. Remarkably, there was a significant reduction in plasma temperature fluctuations across four pressed samples, with a standard deviation of 108.53. Furthermore, we undertook a classification analysis employing support vector machine models to corroborate the generalization efficacy of the sample preparation technique. Dried and pressed samples demonstrated notably higher classification accuracy, precision, and recall (all >93%) compared to frozen and fresh samples, where these metrics remained below 86%. The performance of the SVM model was ultimately evaluated using Receiver Operating Characteristic (ROC) curves and the Area Under the Curve (AUC). The AUC for the frozen, fresh, dried, and pressed samples was 0.854, 0.907, 0.989, and 0.996, respectively. The findings revealed that the pressing method exhibited superior performance, followed by drying, fresh slicing, and freezing, in descending order of effectiveness.


Asunto(s)
Rayos Láser , Análisis Espectral , Animales , Porcinos , Análisis Espectral/métodos , Máquina de Vectores de Soporte , Relación Señal-Ruido , Carne de Cerdo/análisis , Congelación
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