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1.
Eur Radiol ; 31(7): 4595-4605, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33443602

RESUMEN

OBJECTIVE: The aim of this study was (1) to investigate the application of texture analysis of choline PET/CT images in prostate cancer (PCa) patients and (2) to propose a machine-learning radiomics model able to select PET features predictive of disease progression in PCa patients with a same high-risk class at restaging. MATERIAL AND METHODS: Ninety-four high-risk PCa patients who underwent restaging Cho-PET/CT were analyzed. Follow-up data were recorded for a minimum of 13 months after the PET/CT scan. PET images were imported in LIFEx toolbox to extract 51 features from each lesion. A statistical system based on correlation matrix and point-biserial-correlation coefficient has been implemented for features reduction and selection, while Discriminant analysis (DA) was used as a method for features classification in a whole sample and sub-groups for primary tumor or local relapse (T), nodal disease (N), and metastatic disease (M). RESULTS: In the whole group, 2 feature (HISTO_Entropy_log10; HISTO_Energy_Uniformity) results were able to discriminate the occurrence of disease progression at follow-up, obtaining the best performance in DA classification (sensitivity 47.1%, specificity 76.5%, positive predictive value (PPV) 46.7%, and accuracy 67.6%). In the sub-group analysis, the best performance in DA classification for T was obtained by selecting 3 features (SUVmin; SHAPE_Sphericity; GLCM_Correlation) with a sensitivity of 91.6%, specificity 84.1%, PPV 79.1%, and accuracy 87%; for N by selecting 2 features (HISTO = _Energy Uniformity; GLZLM_SZLGE) with a sensitivity of 68.1%, specificity 91.4%, PPV 83%, and accuracy 82.6%; and for M by selecting 2 features (HISTO_Entropy_log10 - HISTO_Entropy_log2) with a sensitivity 64.4%, specificity 74.6%, PPV 40.6%, and accuracy 72.5%. CONCLUSION: This machine learning model demonstrated to be feasible and useful to select Cho-PET features for T, N, and M with valuable association with high-risk PCa patients' outcomes. KEY POINTS: • Artificial intelligence applications are feasible and useful to select Cho-PET features. • Our model demonstrated the presence of specific features for T, N, and M with valuable association with high-risk PCa patients' outcomes. • Further prospective studies are necessary to confirm our results and to develop the application of artificial intelligence in PET imaging of PCa.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Inteligencia Artificial , Colina/análogos & derivados , Humanos , Aprendizaje Automático , Masculino , Recurrencia Local de Neoplasia , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico por imagen
2.
BMC Bioinformatics ; 21(Suppl 8): 325, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-32938360

RESUMEN

BACKGROUND: Positron Emission Tomography (PET) is increasingly utilized in radiomics studies for treatment evaluation purposes. Nevertheless, lesion volume identification in PET images is a critical and still challenging step in the process of radiomics, due to the low spatial resolution and high noise level of PET images. Currently, the biological target volume (BTV) is manually contoured by nuclear physicians, with a time expensive and operator-dependent procedure. This study aims to obtain BTVs from cerebral metastases in patients who underwent L-[11C]methionine (11C-MET) PET, using a fully automatic procedure and to use these BTVs to extract radiomics features to stratify between patients who respond to treatment or not. For these purposes, 31 brain metastases, for predictive evaluation, and 25 ones, for follow-up evaluation after treatment, were delineated using the proposed method. Successively, 11C-MET PET studies and related volumetric segmentations were used to extract 108 features to investigate the potential application of radiomics analysis in patients with brain metastases. A novel statistical system has been implemented for feature reduction and selection, while discriminant analysis was used as a method for feature classification. RESULTS: For predictive evaluation, 3 features (asphericity, low-intensity run emphasis, and complexity) were able to discriminate between responder and non-responder patients, after feature reduction and selection. Best performance in patient discrimination was obtained using the combination of the three selected features (sensitivity 81.23%, specificity 73.97%, and accuracy 78.27%) compared to the use of all features. Secondly, for follow-up evaluation, 8 features (SUVmean, SULpeak, SUVmin, SULpeak prod-surface-area, SUVmean prod-sphericity, surface mean SUV 3, SULpeak prod-sphericity, and second angular moment) were selected with optimal performance in discriminant analysis classification (sensitivity 86.28%, specificity 87.75%, and accuracy 86.57%) outperforming the use of all features. CONCLUSIONS: The proposed system is able i) to extract 108 features for each automatically segmented lesion and ii) to select a sub-panel of 11C-MET PET features (3 and 8 in the case of predictive and follow-up evaluation), with valuable association with patient outcome. We believe that our model can be useful to improve treatment response and prognosis evaluation, potentially allowing the personalization of cancer treatment plans.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Neoplasias Encefálicas/secundario , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico
3.
Int J Mol Sci ; 21(6)2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32178390

RESUMEN

The growing trend for women to postpone childbearing has resulted in a dramatic increase in the incidence of aneuploid pregnancies. Despite the importance to human reproductive health, the events precipitating female age-related meiotic errors are poorly understood. To gain new insight into the molecular basis of age-related chromosome missegregation in human oocytes, we combined the transcriptome profiles of twenty single oocytes (derived from females divided into two groups according to age <35 and ≥35 years) with their chromosome status obtained by array comparative genomic hybridization (aCGH). Furthermore, we compared the transcription profile of the single oocyte with the surrounding cumulus cells (CCs). RNA-seq data showed differences in gene expression between young and old oocytes. Dysregulated genes play a role in important biological processes such as gene transcription regulation, cytoskeleton organization, pathways related to RNA maturation and translation. The comparison of the transcription profile of the oocyte and the corresponding CCs highlighted the differential expression of genes belonging to the G protein-coupled receptor superfamily. Finally, we detected the loss of a X chromosome in two oocytes derived from women belonging to the ≥35 years age group. These aneuploidies may be caused by the detriment of REEP4, an endoplasmic reticulum protein, in women aged ≥35 years. Here we gained new insight into the complex regulatory circuit between the oocyte and the surrounding CCs and uncovered a new putative molecular basis of age-related chromosome missegregation in human oocytes.


Asunto(s)
Cromosomas/genética , Oocitos/fisiología , Transcriptoma/genética , Adulto , Aneuploidia , Células Cultivadas , Hibridación Genómica Comparativa/métodos , Células del Cúmulo/fisiología , Femenino , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica/genética , Humanos , Masculino , Análisis por Micromatrices/métodos , Embarazo , Adulto Joven
4.
Anal Chem ; 90(12): 7450-7457, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29791795

RESUMEN

In the last few decades, new types of cell cultures have been introduced to provide better cell survival and development, with micro- and nanoenvironmental physicochemical conditions aimed at mimicking those present in vivo. However, despite the efforts made, the systems available to date are often difficult to replicate and use. Here, an easy-to-use surface-acoustic-wave (SAW)-based platform is presented for realizing dynamic cell cultures that is compatible with standard optical microscopes, incubators, and cell-culture dishes. The SAW chip is coupled to a standard Petri dish via a polydimethylsiloxane (PDMS) disc and consists of a lithium niobate (LN) substrate on which gold interdigital transducers (IDTs) are patterned to generate the SAWs and induce acoustic streaming in the dish. SAW excitation is verified and characterized by laser Doppler vibrometry, and the fluid dynamics is studied by microparticle image velocimetry (µPIV). Heating is measured by an infrared (IR) thermal camera. We finally tested this device with the U-937 monocyte cell line for viability and proliferation and cell-morphological analysis. The data demonstrate that it is possible to induce significant fluid recirculation within the Petri dish while maintaining negligible heating. Remarkably, cell proliferation in this condition was enhanced by 36 ± 12% with respect to those of standard static cultures. Finally, we show that cell death does not increase and that cell morphology is not altered in the presence of SAWs. This device is the first demonstration that SAW-induced streaming can mechanically improve cell proliferation and further supports the great versatility and biocompatibility of the SAW technology for cell manipulation.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Sonido , Biotecnología/métodos , Proliferación Celular , Calor , Humanos , Hidrodinámica , Células U937
5.
Reprod Biomed Online ; 29(2): 259-66, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24947067

RESUMEN

This study investigated the relationships between ovarian endometrioma size, ovarian responsiveness and the number of retrieved oocytes following ovarian stimulation. A prospective study was conducted in a public clinical assisted reproduction centre. A total of 64 infertile women with monolateral endometriomas undergoing IVF or intracytoplasmic sperm injection were included in the study. The total number of follicles, number of follicles ≥ 16 mm and number of oocytes retrieved of ovaries containing endometrioma and normal ovaries were compared. Multivariate linear regression was used to assess whether number of follicles and collected oocytes varied by endometrioma size, age, basal FSH concentration. Significantly lower numbers of follicles ≥ 16 mm (P = 0.024) and oocytes retrieved (P = 0.001) in the ovaries containing endometrioma were observed. In patients with endometriomas ≥ 30 mm, endometrioma size was the most influential contributor to the total number of follicles and oocytes retrieved. Ovarian endometriomas result in reduced response to ovarian stimulation, compared with the response of the contralateral normal ovary in the same individual. In case of endometriomas <30 mm, basal FSH concentration remains the most important prognostic factor for oocyte retrieval.


Asunto(s)
Neoplasias Endometriales/fisiopatología , Endometriosis/fisiopatología , Ovario/fisiopatología , Técnicas Reproductivas Asistidas , Adulto , Femenino , Hormona Folículo Estimulante/metabolismo , Humanos , Estudios Prospectivos
6.
Qual Quant ; 57(2): 1701-1723, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35694109

RESUMEN

The still ongoing pandemic of SARS-CoV-2 virus and COVID-19 disease, affecting the population worldwide, has demonstrated the need of more accurate methodologies for assessing, monitoring, and controlling an outbreak of such devastating proportions. Authoritative attempts have been made in traditional fields of medicine (epidemiology, virology, infectiology) to address these shortcomings, mainly by relying on mathematical and statistical modeling. However, here, we propose approaching the methodological work from a different, and to some extent alternative, standpoint. Applied systematically, the concepts and tools of statistical engineering and quality management, developed not only in healthcare settings, but also in other scientific contexts, can be very useful in assessing, monitoring, and controlling pandemic events. We propose a methodology based on a set of tools and techniques, formulas, graphs, and tables to support the decision-making concerning the management of a pandemic like COVID-19. This methodological body is hereby named Pandemetrics. This name intends to emphasize the peculiarity of our approach to measuring, and graphically presenting the unique context of the COVID-19 pandemic.

7.
J Clin Med ; 11(3)2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35160131

RESUMEN

BACKGROUND AND AIMS: Failure of the embryo to implant causes about three-fourths of lost pregnancies. Female genital tract microbiota has been associated to Assisted Reproductive Technologies (ART) outcomes. The objective of this study was to analyze the microbiota of human cervical swab and to correlate these findings with the ART outcomes. MATERIALS AND METHODS: In this study, 88 cervical swabs were collected from women undergoing ART cycles, with various causes of infertility, at the beginning of the ART protocols. After microbial DNA extraction, V3-V4 variable regions of the 16S rRNA gene were amplified and sequenced on the Illumina MiSeq platform. PEnalized LOgistic Regression Analysis (PELORA) was performed to identify clusters of bacterial populations with differential abundances between patients with unfavorable and favorable pregnancy outcome groups, respectively. RESULTS: We identified a core of microorganisms at lower taxonomic levels that were predictive of women's pregnancy outcomes. Statistically significant differences were identified at species levels with Lactobacillus salivarius, Lactobacillus rhamnosus among others. Moreover the abundance of Lactobacillus crispatus and iners, respectively increased and decreased in favorable group as compared to unfavorable group, resulted within the core of microorganisms associated to positive ART outcome. Although the predominance of lactobacilli is generally considered to be advantageous for ART outcome, we found that also the presence of Bifidobacterium (together with the other lactobacilli) was more abundant in the favorable group. DISCUSSION: Cervix is colonized by microorganisms which can play a role in ART outcomes as seen by an overall decrease in embryo attachment rates and pregnancy rates in both fertile and infertile women. If confirmed in a larger cohort, the abundance of these bacteria can be useful not only as a marker of unfavorable pregnancy outcome but also they may open the way to new interventional strategies based on genital tract microbiota manipulation in order to increase the pregnancy rates in woman undergoing assisted reproductive technologies.

8.
Insects ; 11(9)2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32882909

RESUMEN

Control of the plum fruit moth, Grapholita funebrana Treitschke (Lepidoptera: Tortricidae), has been mainly based on the use of chemical insecticides, which can cause undesirable side effects, leading to a growing interest towards alternative sustainable strategies. The aim of this study was to evaluate the effect of the mating disruption technique on G. funebrana infestation in plum orchards, by comparing the number of male captures in pheromone-baited traps, and evaluating the damage to fruits in plots treated with the pheromone dispersers and in control plots. The study was carried out in 2012 and 2014 in three organic plum orchards, on the cultivars Angeleno, Friar, President and Stanley. To evaluate the pheromone emission curve of the dispensers from the openings to the end of the trials, a chemical analysis was carried out by solid phase micro-extraction followed by gas chromatography, followed by mass spectrometry. In all years and orchards the mean number of males caught in traps placed in the treatment plots was always significantly lower than untreated plots. Pheromone emission from the dispensers was highest at the opening, and was still considerable at 54 days of field exposure, while it significantly decreased after 72 days of field exposure. Cultivar was confirmed to be an essential factor in determining the fruit infestation level. Pheromone treatment significantly reduced fruit infestation, but not economic damage.

9.
Plants (Basel) ; 9(11)2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-33233807

RESUMEN

Tomato brown rugose fruit virus (ToBRFV) is a highly infectious virus, that is becoming a threat to tomato production worldwide. In this work we evaluated the localization of ToBRFV particles in tomato seeds, its seed transmission rate and efficacy of disinfection, and the effects of different thermal- and chemical-based treatments on ToBRFV-infected seeds' germination. Analyses demonstrated that ToBRFV was located in the seed coat, sometime in the endosperm, but never in the embryo; its transmission from infected seeds to plantlets occurs by micro-lesions during the germination. The ToBRFV seed transmission rate was 2.8% in cotyledons and 1.8% in the third true leaf. Regarding the different disinfection treatments, they returned 100% of germination at 14 days post-treatment (dpt), except for the treatment with 2% hydrochloric acid +1.5% sodium hypochlorite for 24 h, for which no seed germinated after 14 dpt. All treatments have the ability to inactivate ToBRFV, but in six out of seven treatments ToBRFV was still detectable by RT-qPCR. These results raise many questions about the correct way to carry out diagnosis at customs. To our knowledge, this is the first study on the effective localization of ToBRFV particles in seeds.

10.
Artif Intell Med ; 94: 67-78, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30871684

RESUMEN

In the context of cancer delineation using positron emission tomography datasets, we present an innovative approach which purpose is to tackle the real-time, three-dimensional segmentation task in a full, or at least nearly full automatized way. The approach comprises a preliminary initialization phase where the user highlights a region of interest around the cancer on just one slice of the tomographic dataset. The algorithm takes care of identifying an optimal and user-independent region of interest around the anomalous tissue and located on the slice containing the highest standardized uptake value so to start the successive segmentation task. The three-dimensional volume is then reconstructed using a slice-by-slice marching approach until a suitable automatic stop condition is met. On each slice, the segmentation is performed using an enhanced local active contour based on the minimization of a novel energy functional which combines the information provided by a machine learning component, the discriminant analysis in the present study. As a result, the whole algorithm is almost completely automatic and the output segmentation is independent from the input provided by the user. Phantom experiments comprising spheres and zeolites, and clinical cases comprising various body districts (lung, brain, and head and neck), and two different radio-tracers (18 F-fluoro-2-deoxy-d-glucose, and 11C-labeled Methionine) were used to assess the algorithm performances. Phantom experiments with spheres and with zeolites showed a dice similarity coefficient above 90% and 80%, respectively. Clinical cases showed high agreement with the gold standard (R2 = 0.98). These results indicate that the proposed method can be efficiently applied in the clinical routine with potential benefit for the treatment response assessment, and targeting in radiotherapy.


Asunto(s)
Algoritmos , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Análisis Discriminante , Humanos , Estudios Retrospectivos
11.
JBRA Assist Reprod ; 21(2): 89-93, 2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28609274

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the efficacy of a non-expensive, easy and fast technique (direct micro swim-up) for sperm preparation in intracytoplasmic sperm injection (ICSI) treatments without the use of centrifuge. METHODS: We carried out a multicentric study in which a total of 140 ICSI-cycles were included. Sibling oocytes were divided into two groups according to semen preparation procedures: group A, discontinuous gradients (DG) (oocytes n=668), and group B, direct micro swim-up (MSU) (oocytes n=660). We analyzed differences in some key performance indicators. RESULTS: Fertilization rates were not statistically different between the DG and MSU groups (76.0% vs. 81.8%, respectively, p=0.248); while significant differences were found in blastulation rates per fertilized oocytes (41.7% vs. 58.5%, p=0.009), blastulation rates per D3 embryos (46.1% vs. 63.7%, p=0.045), and pregnancy rates (25.8% vs. 41.9%, p=0.045). The abortion rate was reduced in the MSU group as compared to DG, but not in a significant manner (12.9% vs. 29.4%, p=0.161). CONCLUSION: The MSU procedure has the advantage of reducing costs, time and mismatches, while ensuring comparable, and in some cases, better results than DG treatments. This technique can therefore be used as an alternative method to other conventional semen treatments.


Asunto(s)
Centrifugación por Gradiente de Densidad/métodos , Fertilización In Vitro/estadística & datos numéricos , Inyecciones de Esperma Intracitoplasmáticas/estadística & datos numéricos , Espermatozoides/citología , Blástula , Daño del ADN , Femenino , Humanos , Masculino , Embarazo , Resultado del Embarazo/epidemiología , Estudios Retrospectivos
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