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1.
Int J Legal Med ; 138(4): 1265-1272, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38433135

RESUMEN

Interest in recovering DNA from the surface of ammunition evidence for genotyping has increased over the past few years. Numerous studies have examined a variety of methods to maximize DNA recovery from these types of challenging samples, but successful DNA profiling has been inconsistent. Low amounts of DNA and PCR inhibition due to metal ions have been suggested as the leading causes of poor results; however, no study quantitatively examined the presence of metal ions at various stages of the DNA analysis workflow from DNA collection through to amplification. In this study, the effectiveness of six different DNA collection and purification methods commonly used by forensic laboratories to process brass ammunition for DNA evidence was investigated. The amount of copper, zinc, and other metals co-recovered from fired and unfired brass casings during DNA collection (using numerous soaking, swabbing, and direct PCR protocols) was quantified via Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES). This same panel of metals was subsequently quantified after DNA lysis and purification steps. Results demonstrated that low amounts of DNA, DNA damage, and degradation are more detrimental to STR typing results than PCR inhibition, as metal ions were successfully removed by all DNA purification methods tested. Furthermore, the use of metal ion chelators increased the amount of DNA recovered and number of reportable STR alleles. This research informs the forensic community on the most effective way to collect and process trace amounts of biological material from brass ammunition and similar evidence.


Asunto(s)
Dermatoglifia del ADN , ADN , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa , Manejo de Especímenes , Dermatoglifia del ADN/métodos , Humanos , ADN/aislamiento & purificación , Manejo de Especímenes/métodos , Zinc , Armas de Fuego , Metales , Cobre , Quelantes/química
2.
Pharmaceutics ; 16(2)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38399296

RESUMEN

The material library is an emerging, new data-driven approach for developing pharmaceutical process models. How many materials or samples should be involved in a particular application scenario is unclear, and the impact of sample size on process modeling is worth discussing. In this work, the direct compression process was taken as the research object, and the effects of different sample sizes of material libraries on partial least squares (PLS) modeling in the prediction of tablet tensile strength were investigated. A primary material library comprising 45 materials was built. Then, material subsets containing 5 × i (i = 1, 2, 3, …, 8) materials were sampled from the primary material library. Each subset underwent sampling 1000 times to analyze variations in model fitting performance. Both hierarchical sampling and random sampling were employed and compared, with hierarchical sampling implemented with the help of the tabletability classification index d. For each subset, modeling data were organized, incorporating 18 physical properties and tableting pressure as the independent variables and tablet tensile strength as the dependent variable. A series of chemometric indicators was used to assess model performance and find important materials for model training. It was found that the minimum R2 and RMSE values reached their maximum, and the corresponding values were kept almost unchanged when the sample sizes varied from 20 to 45. When the sample size was smaller than 15, the hierarchical sampling method was more reliable in avoiding low-quality few-shot PLS models than the random sampling method. Two important materials were identified as useful for building an initial material library. Overall, this work demonstrated that as the number of materials increased, the model's reliability improved. It also highlighted the potential for effective few-shot modeling on a small material library by controlling its information richness.

3.
Quant Imaging Med Surg ; 13(4): 2634-2646, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37064402

RESUMEN

Background: The American College of Radiology Breast Imaging Reporting and Data System (ACR BI-RADS) used with ultrasonography cannot guide the individual management of solid breast tumors, but preoperative core biopsy categories (CBCs) can. We aimed to use machine learning to analyze clinical and ultrasonic features for predicting CBCs and to aid in the development of a new ultrasound (US) imaging reporting system for solid tumors of the breast. Methods: This retrospective study included women with solid breast tumors who underwent US-guided core needle biopsy from March 1, 2019, to December 31, 2019. All patients were randomly assigned to a training or validation cohort (7:3 ratio). CBC was predicted using 5 machine learning models: random forest (RF), support vector machine (SVM), k-nearest-neighbor (KNN), multilayer perceptron (MLP), and ridge regression (RR). In the validation cohort, the area under the curve (AUC) and accuracy were ascertained for every algorithm. Based on AUC values, the optimal algorithm was determined, and the features' importance was depicted. Results: A total of 1,082 female patients were included (age range, 12-96 years; mean age ± standard deviation, 42.22±13.37 years). The proportion of the 4 CBCs was 4% (44/1,185) for the B1 group, 60% (714/1,185) for the B2 group, 5% (57/1,185) for the B3 group, and 31% (370/1,185) for the B5 group. In the validation cohort, AUCs of the optimal algorithm constructed RF were 0.78, 0.88, 0.64, and 0.92 for B1, B2, B3, and B5, respectively, with an accuracy of 0.82. Conclusions: Machine learning could strongly predict CBC, particularly in B2 and B5 categories of solid breast tumors, with RF being the optimal machine learning model.

4.
Biotechnol Rep (Amst) ; 30: e00621, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34026574

RESUMEN

An autoflocculating microalgal strain was isolated from coal mine effluent wastewater which was named as Scenedesmus sp. NC1 after morphological and molecularly characterization. Further analysis of internal transcribed spacer 2 (ITS2) and compensatory base changes (CBCs) showed it does not belong to the clade comprising Scenedesmus sensu stricto. In stationary phase of growth, Scenedesmus sp. NC1 exhibited excellent autoflocculation efficiency (> 88 %) within 150 min of setting. Temperature, pH, and inorganic metals exhibited minor influence on the autoflocculation activity of Scenedesmus sp. NC1. The fatty acid profiling of Scenedesmus sp.NC1 showed that palmitic acid (C16:0), oleic acid (C18:1), and stearic acid (18:0) accounted for more than 68 % of total fatty acids. Moreover, Scenedesmus sp. NC1 demonstrated significant bioflocculation potential over non-flocculating freshwater microalgae, Chlorella sp. NCQ and Micractinium sp. NCS2. Hence, Scenedesmus sp. NC1 could be effective for economical harvesting of other non-flocculating microalgae for productions of biodiesel and other metabolites.

5.
Life (Basel) ; 11(3)2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33800295

RESUMEN

The mosquito Anopheles (Cellia) subpictus sensu lato (s.l.) is a major secondary vector of malaria in Sri Lanka. The sibling species composition in this species complex in Sri Lanka remains debatable. Compensatory base changes (CBCs) in the secondary structures of internal transcribed spacer 2 (ITS2) are reliable sources to predict sexual incompatibility among closely related species. The objective of the present study was to investigate the An. subpictus s.l. populations in Sri Lanka using the CBC analysis. Mosquito DNA was amplified and sequenced for the ITS2 region. The sequences were annotated using ITS2 Database. ITS2 secondary structures were constructed and analyzed for CBCs using various bioinformatics tools. The ITS2 regions consisted of two different lengths, 575 bp and 480 bp. The two CBCs and three hemi CBCs identified in the present study suggest that there may be at least two sexually incompatible sibling species. In conclusion, it is likely that there may be only two reproductively isolated sibling species in the An. subpictus species complex in Sri Lanka. However, due to high divergence of ITS2 in these species, it is reasonable to assume that they may be undergoing a speciation event to separate as a distinct species.

6.
Cell Rep ; 32(11): 108144, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32937137

RESUMEN

Retinal bipolar cells (BCs) connect with photoreceptors and relay visual information to retinal ganglion cells (RGCs). Retina-specific deletion of Lhx4 in mice results in a visual defect resembling human congenital stationary night blindness. This visual dysfunction results from the absence of rod bipolar cells (RBCs) and the loss of selective rod-connecting cone bipolar cell (CBC) subtypes and AII amacrine cells (ACs). Inactivation of Lhx4 causes the apoptosis of BCs and cell fate switch from some BCs to ACs, whereas Lhx4 overexpression promotes BC genesis. Moreover, Lhx4 positively regulates Lhx3 expression to drive the fate choice of type 2 BCs over the GABAergic ACs. Lhx4 inactivation ablates Bhlhe23 expression, whereas overexpression of Bhlhe23 partially rescues RBC development in the absence of Lhx4. Thus, by acting upstream of Bhlhe23, Prdm8, Fezf2, Lhx3, and other BC genes, Lhx4, together with Isl1, could play essential roles in regulating the subtype-specific development of RBCs and CBCs.


Asunto(s)
Diferenciación Celular , Proteínas con Homeodominio LIM/metabolismo , Células Bipolares de la Retina/metabolismo , Células Fotorreceptoras Retinianas Conos/metabolismo , Factores de Transcripción/metabolismo , Envejecimiento/patología , Células Amacrinas/metabolismo , Células Amacrinas/patología , Animales , Apoptosis , Electrorretinografía , Proteínas con Homeodominio LIM/deficiencia , Ratones , Visión Nocturna , Células Bipolares de la Retina/patología , Células Fotorreceptoras Retinianas Conos/patología , Factores de Transcripción/deficiencia , Transcriptoma/genética
7.
Stem Cell Res Ther ; 11(1): 349, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32787930

RESUMEN

Paneth cells (PCs) are located at the bottom of small intestinal crypts and play an important role in maintaining the stability of the intestinal tract. Previous studies reported on how PCs shape the intestinal microbiota or the response to the immune system. Recent studies have determined that PCs play an important role in the regulation of the homeostasis of intestinal epithelial cells. PCs can regulate the function and homeostasis of intestinal stem cells through several mechanisms. On the one hand, under pathological conditions, PCs can be dedifferentiated into stem cells to promote the repair of intestinal tissues. On the other hand, PCs can regulate stem cell proliferation by secreting a variety of hormones (such as wnt3a) or metabolic intermediates. In addition, we summarise key signalling pathways that affect PC differentiation and mutual effect with intestinal stem cells. In this review, we introduce the diverse functions of PCs in the intestine.


Asunto(s)
Intestinos , Células de Paneth , Células Madre , Diferenciación Celular , Intestinos/citología , Transducción de Señal
8.
Int J Pharm ; 572: 118742, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31648016

RESUMEN

In this paper, a compression behavior classification system (CBCS) for direct compression (DC) pharmaceutical powders is presented. Seven descriptors from a series of compression models for powder compressibility, compactibility and tabletability analysis were included in the CBCS. A new tabletability index d was proposed to differentiate three categories of tensile strength (TS) vs. pressure relationships, and its physical meaning was explained thoroughly. 130 materials containing diverse pharmaceutical excipients and natural product powders (NPPs) were fully characterized and were compiled into an in-house developed material library, in which 70 materials with potential DC applications were used to justify the effectiveness of the CBCS. Principle component analysis (PCA) was used to uncover the latent structure of compression variables. Moreover, partial least squares (PLS) regression models are established in prediction of both tablet TS and solid fraction (SF) based on the raw materials' physical characteristics, the compression behavior indices and the compression force. The obtained scores and loadings are used to group the materials and the compression variables, respectively. Different categories of tabletability for DC powders were clearly clustered along two orthogonal directions pointing to the index d and the compression force. Finally, a multi-objective design space was identified under the latent variable space, summarizing the operationally possible region for both material properties and compression pressure required in DC tablet formulation design.


Asunto(s)
Composición de Medicamentos/métodos , Polvos/química , Comprimidos/química , Química Farmacéutica/métodos , Fuerza Compresiva , Excipientes/química , Análisis de los Mínimos Cuadrados , Fenómenos Mecánicos , Tamaño de la Partícula , Porosidad , Presión , Resistencia a la Tracción
9.
Breast ; 45: 36-42, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30826525

RESUMEN

The primary aim of the international advance breast cancer (ABC) guidelines are to guide treatment decisions in many different healthcare settings, but need adaptations due to different access to care. These guidelines are based on the most up-to-date evidence. However, Chinese experts have a different national condition and policies to face. The Chinese Anti-Cancer Association Committee of Breast Cancer Society guideline (CBCS guideline) is to guide treatments and to reflect unmet needs of Chinese breast cancer patients. Although, most of the recommendations in the two guidelines are the same, some of them are different. In this article, with regard to country-specific peculiarities, a working group of Chinese breast cancer experts compare the similarities and differences between the ABC guideline and CBCS guideline and commented on the voting results of the ABC panelists. We also discuss why these differences exist, such as lack of access, different tumor biology and epidemiology, and even different culture. The money which patients have to pay out of pocket for their medical cost and the availability of drugs lie at the heart of the issues of guideline differences.


Asunto(s)
Protocolos Antineoplásicos/normas , Neoplasias de la Mama , Guías de Práctica Clínica como Asunto/normas , Sociedades Médicas/normas , China , Consenso , Femenino , Humanos
10.
Mol Phylogenet Evol ; 102: 128-44, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27261253

RESUMEN

Morphological and molecular delimitation of Spirostomum species is currently under debate. We addressed species boundaries within the genus Spirostomum, using the ITS1-5.8S-ITS2 region and the secondary structure of the ITS2 molecule, and 18S and 28S (D1D2) sequences additionally. The Spirostomum ITS region is among the shortest within the ciliates hitherto studied. The Spirostomum ITS2 molecule matches the "ring model", but exhibits only two helices radiating from a common loop. According to comparative analyses, they very likely correspond to helices II and III of other eukaryotes. Our phylogenetic analyses of the ITS region revealed a complex genealogical structure within the genus Spirostomum. However, boundaries among Spirostomum species could not be unambiguously determined either by phylogenetic trees, networks or sequence divergence cutoffs, because ITS2 sequences transcended species boundaries of the following morphospecies: S. ambiguum, S. minus, S. subtilis and S. teres. According to molecular diversity analysis, this is very likely caused by polymorphism in S. minus and S. teres, and by the lack of variability in S. ambiguum and S. subtilis. No compensatory base changes (CBCs) were detected in helices of the ITS2 molecule between different Spirostomum species, documenting that CBC analysis per se is not able to effectively discriminate Spirostomum species.


Asunto(s)
Cilióforos/clasificación , ADN Espaciador Ribosómico/genética , Animales , Secuencia de Bases , Cilióforos/genética , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/metabolismo , Variación Genética , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN
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