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1.
Int J Legal Med ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38561435

RESUMEN

Initial experiences with magnetic resonance imaging (MRI) of living strangulation victims demonstrated additional findings of internal injuries compared to the standard clinical forensic examination. However, existing studies on the use of MRI for this purpose mostly focused on the first 48 h after the incident. The aims of this study were (a) to evaluate the longitudinal visibility of MRI findings after violence against the neck by performing two MRI examinations within 12 days and a minimum of four days between both MRI scans and (b) to assess which MRI sequences were most helpful for the detection of injuries. Twenty strangulation victims participated in this study and underwent one (n = 8) or two (n = 12) MRI scans. The first MRI examination was conducted during the first five days, the second five to 12 days after the incident. Two blinded radiologists assessed the MRI data and looked for lesions in the structures of the neck. In total, 140 findings were reported in the 32 MRI examinations. Most of the findings were detected in the thyroid and the muscles of the neck. T2-weighted SPACE with fat suppression, T1-weighted TSE and T1-weighted MPRAGE were rated as the most helpful MRI sequences. Subjects who showed findings in the initial scan also demonstrated comparable results in the second scan, which was performed on average 8.4 days after the incident. Our results show that even up to 12 days after the incident, the criminal proceeding of strangulation cases may greatly profit from the information provided by an MRI examination of the neck in addition to the standard clinical forensic examination.

2.
J Microbiol Biol Educ ; 24(2)2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37614877

RESUMEN

Course-based undergraduate research experiences (CUREs) are tools used to introduce students to authentic participation in science. Several specific CUREs have been shown to benefit students' interest and retention in the biological sciences. Nevertheless, CUREs vary greatly in terms of their context, methodology, and degree of research authenticity, so different types of CUREs may differently influence student outcomes. This programmatic diversity poses a challenge to educators who want to better understand which course components and features are reliably present in a CURE curriculum. To address these issues, we identified, catalogued, and classified 112 potential features of CUREs across the biosciences. To develop the list, we interviewed instructors experienced with teaching individual and large networked CUREs across a diversity of the biological disciplines, including: Squirrel-Net (field-based animal behavior), SEA-PHAGES (wet lab microbiology and computational microbiology), Tiny Earth (environmental and wet lab microbiology), PARE (environmental microbiology), and the Genomics Education Partnership (eukaryotic computational biology). Twenty-five interviewees contributed expert content in terms of CURE features and classification of those items into an organized list. The resulting list's categories encompasses student experiences with the following: (i) the scientific process; (ii) technical aspects of science; (iii) the professional development associated with research; and (iv) building scientific identity. The most striking insight was that CUREs vary widely in terms of which features they contain, since different CUREs will by necessity have different approaches to science and student involvement. We also identified several features commonly thought to be crucial to CUREs yet have ambiguous definitions. This ambiguity can potentially confound efforts to make CUREs research-authentic and aligned with the central goals of science. We disambiguate these terms and represent their varied meanings throughout the classification. We also provide instructor-friendly supplementary worksheets along with considerations for instructors interested in expanding their CURE course design, instruction, and equity.

3.
Forensic Sci Int ; 348: 111738, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37263059

RESUMEN

Performing magnetic resonance imaging (MRI) of deceased is challenging due to altered body temperatures compared to in vivo temperatures and, hence, requires a temperature correction. This study investigates the possibility to correct brain MRI parameters real-time and non invasively based on the forehead temperature. 17 post mortem cases were included and their forehead temperatures were measured continuously during the in situ brain MRI protocol consisting of a diffusion tensor imaging, multi-contrast spin echo, multi-echo gradient echo and inversion recovery spin echo sequence. Linear models were fitted to the quantitative MRI parameters in a forensically interesting temperature range for white matter, cerebral cortex and deep gray matter, separately, and the influence of the forehead temperature on the MRI parameters was determined. A statistically significant temperature sensitivity was found for T2 and mean diffusivity in white matter, for T1 in cerebral cortex, as well as for T1 and mean diffusivity in deep gray matter. Linear models were computed to temperature correct these MRI parameters in in situ post mortem scans to allow their comparison regardless of temperature. The here presented real-time and non invasive temperature correction method for the brain presents a crucial precondition for quantitative in situ post mortem MRI.


Asunto(s)
Imagen de Difusión Tensora , Frente , Temperatura , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología
4.
J Therm Biol ; 115: 103615, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37390676

RESUMEN

It is well known that magnetic resonance (MR) imaging is temperature sensitive, which is highly relevant for post mortem examinations. Therefore, the determination of the exact temperature of the investigated body site, e.g. the brain, is crucial. However, direct temperature measurements are invasive and inconvenient. Thus, in view of post mortem MR imaging of the brain, this study aims at investigating the relation between the brain and the forehead temperature for modelling the brain temperature based on the non-invasive forehead temperature. In addition, the brain temperature will be compared to the rectal temperature. Brain temperature profiles measured in the longitudinal fissure between the brain hemispheres, as well as rectal and forehead temperature profiles of 16 deceased were acquired continuously. Linear mixed, linear, quadratic and cubic models were fitted to the relation between the longitudinal fissure and the forehead and between the longitudinal fissure and the rectal temperature, respectively. Highest adjusted R2 values were found between the longitudinal fissure and the forehead temperature, as well as between the longitudinal fissure and the rectal temperature using a linear mixed model including the sex, environmental temperature and humidity as fixed effects. The results indicate that the forehead, as well as the rectal temperature, can be used to model the brain temperature measured in the longitudinal fissure. Comparable fit results were observed for the longitudinal fissure-forehead temperature relation and for the longitudinal fissure-rectal temperature relation. Combined with the fact that the forehead temperature overcomes the problem of measurement invasiveness, the results suggest using the forehead temperature for modelling the brain temperature in the longitudinal fissure.


Asunto(s)
Temperatura Corporal , Termómetros , Temperatura , Frente , Autopsia , Encéfalo
6.
Forensic Sci Int ; 341: 111494, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36242925

RESUMEN

The fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) sequence aims at suppressing the signal of the cerebrospinal fluid (CSF) by acquiring images at the time point at which the longitudinal magnetization and therefore the signal of CSF is zero. This time point is also called the null point inversion time (TInull). However, the FLAIR sequence is impaired by the temperature dependency of TInull in post mortem MRI due to the lower body temperature of the deceased subject. Therefore, the temperature correction of TInull is crucial for correctly suppressing the CSF signal in post mortem FLAIR imaging. Thus, the goal of this study was to determine the temperature effect on post mortem TInull for achieving a robust suppression of the CSF signal in in situ post mortem MRI using the FLAIR sequence. For this purpose, nine deceased subjects underwent an in situ MRI brain examination on a 3 T MRI scanner. TInull of CSF was determined quantitatively based on different FLAIR acquisitions using varying inversion times. The brain and rectal temperatures were determined prior to the MRI scan. A significant positive linear relation was found between TInull of CSF and the brain temperature, as well as between TInull of CSF and the rectal temperature. The found linear relations between TInull and both brain and rectal temperatures allow correcting TInull for varying temperatures of the deceased. This in turn enables an optimal suppression of the CSF signal in future post mortem FLAIR MRI acquisitions.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Cabeza , Autopsia
7.
Forensic Sci Int ; 337: 111376, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35792395

RESUMEN

The post mortem assessment of brain edema is routinely performed during autopsy by forensic pathologists who evaluate the macroscopically visible signs. In this study, the suitability of magnetic resonance imaging (MRI) for a differentiation between edematous and nonedematous brains was examined as an objective, noninvasive and quantitative rating method. In this study, 22 deceased underwent post mortem in situ MRI prior to regular autopsy. Acquired MRI sequences allowed the computation of the quantitative MRI parameters T1, T2, T2*, fractional anisotropy (FA) and mean diffusivity for the cortex, white matter and deep gray matter separately. Beside the autopsy results, which represent the gold standard for rating brain edema, also the normalized cerebral weight (NCW) was determined by dividing the brain weight by the intracranial volume as developed by Bauer et al. [10]. For further examination of the relation of MRI parameters with the NCW, linear regression models were calculated. The results revealed highly significant correlations of the MRI parameters T2 and FA with the NCW in the cortex. These combinations additionally showed the best fitting results of the linear regression models. In conclusion, quantitative MRI is suitable for differentiating edematous from nonedematous brains by calculating T2 and FA in the cortex. A post mortem in situ MRI scan of the brain can, besides delivering morphological information, add relevant and objective information on the edema status of the brain prior to autopsy or when no autopsy is ordered.


Asunto(s)
Edema Encefálico , Sustancia Blanca , Autopsia/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/patología , Edema/diagnóstico por imagen , Edema/patología , Humanos , Imagen por Resonancia Magnética/métodos
8.
MAGMA ; 35(3): 375-387, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34714448

RESUMEN

OBJECTIVE: MRI temperature sensitivity presents a major issue in in situ post mortem MRI (PMMRI), as the tissue temperatures differ from living persons due to passive cooling of the deceased. This study aims at computing brain temperature effects on the MRI parameters to correct for temperature in PMMRI, laying the foundation for future projects on post mortem validation of in vivo MRI techniques. MATERIALS AND METHODS: Brain MRI parameters were assessed in vivo and in situ post mortem using a 3 T MRI scanner. Post mortem brain temperature was measured in situ transethmoidally. The temperature effect was computed by fitting a linear model to the MRI parameters and the corresponding brain temperature. RESULTS: Linear positive temperature correlations were observed for T1, T2* and mean diffusivity in all tissue types. A significant negative correlation was observed for T2 in white matter. Fractional anisotropy revealed significant correlations in all gray matter regions except for the thalamus. DISCUSSION: The linear models will allow to correct for temperature in post mortem MRI. Comparing in vivo to post mortem conditions, the mean diffusivity, in contrast to T1 and T2, revealed additional effects besides temperature, such as cessation of perfusion and active diffusion.


Asunto(s)
Imagen por Resonancia Magnética , Sustancia Blanca , Autopsia , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Temperatura , Sustancia Blanca/diagnóstico por imagen
9.
CBE Life Sci Educ ; 20(4): ar54, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34546099

RESUMEN

Evidence-based teaching practices (EBPs) foster college science, technology, engineering, and mathematics (STEM) students' engagement and performance, yet our knowledge of what contributes to the effectiveness of these practices is less established. We propose a framework that links four social-cognitive variables-students' trust in their instructors, growth mindset, buy-in to instructional practices, and course engagement-to long-standing desired student outcomes of academic performance and intent to persist in science. This framework was tested in classrooms identified as having a high level of EBP implementation with a multi-institutional sample of 2102 undergraduates taught by 14 faculty members. Results indicate that the buy-in framework is a valid representation of college students' learning experiences within EBP contexts overall as well as across underrepresented student groups. In comparison to students' level of growth mindset, students' trust in their instructors was more than twice as predictive of buy-in to how the course was being taught, suggesting that students' views of their instructors are more associated with thriving in a high-EBP course environment than their views of intelligence. This study contributes to the dialogue on transforming undergraduate STEM education by providing a validated student buy-in framework as a lens to understand how EBPs enhance student outcomes.


Asunto(s)
Estudiantes , Confianza , Ingeniería , Humanos , Matemática , Enseñanza , Tecnología
10.
Magn Reson Med ; 86(5): 2703-2715, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34086354

RESUMEN

PURPOSE: R2∗ imaging of brain white matter is well known for being sensitive to the orientation of nerve fibers with respect to the B0 field of the MRI scanner. The goal of this study was to evaluate whether and to which extent fiber orientation dependent R2∗ differs between in vivo and post mortem in situ examinations, and to investigate the influence of varying temperatures and post mortem intervals (PMI). METHODS: Post mortem in situ and in vivo MRI scans were conducted at 3T. R2∗ was acquired with a multi-echo gradient-echo sequence, and the orientation of white matter fibers was computed using diffusion tensor imaging (DTI). Fitting of the measured fiber orientation dependent R2∗ was performed using three different formulations of a previously proposed model. RESULTS: R2∗ increased with increasing fiber angle for in vivo and post mortem in situ examinations, whereby the orientation dependency was lower post mortem. The different formulations of the fiber orientation model resulted in an identical fit, but showed large variations of the estimated parameters. The higher order orientation dependent R2∗ components significantly decreased with decreasing temperature, while the orientation independent R2∗ components showed no significant correlation with either temperature or PMI. CONCLUSION: Although the mean diffusivity is strongly reduced post mortem, we could successfully estimate the fiber angle using DTI. Due to the strong correlation of the higher order orientation dependent R2∗ components with temperature, the decreased R2∗ fiber orientation dependency post mortem in situ might primarily be attributed to the lower brain temperature.


Asunto(s)
Imagen de Difusión Tensora , Sustancia Blanca , Anisotropía , Encéfalo/diagnóstico por imagen , Temperatura , Sustancia Blanca/diagnóstico por imagen
11.
Forensic Sci Int ; 323: 110808, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33971505

RESUMEN

The post mortem evaluation of a brain edema is routinely performed by pathologists based on the macroscopic signs during autopsy. This method represents the current gold standard, but is subjective and observer dependent. Therefore, three post mortem evaluation methods of brain samples were analyzed in this work: histology, wet-dry weight and normalized cerebral weight, which was described in 2020 by Bauer et al. Tissue samples from six different regions of 34 brains were collected and examined both by rating of histological slides and by measuring the water content by using a drying oven. The rating of the histological slides, stained with hematoxylin and eosin, was performed by two pathologists independently. For the water content, the wet weight and the dry weight of each sample were set in relation. The normalized cerebral weight was calculated by dividing the brain weight by the brain volume, which were both determined during autopsy and in computed tomography images, respectively. A fair to moderate interrater agreement was obtained for the histologic evaluation and a significant correlation was present between one rater and the wet-dry weight and the normalized cerebral weight method. When classifying according to the gold standard, a significant difference was detected between the edematous and nonedematous cases by using the wet-dry weight method in the cerebral cortex and by using the normalized cerebral weight method. However, the significant correlations and group differences were limited to the aforementioned results. In conclusion, both the histological and the wet-dry weight method show limited benefits for the classification of brain edema and the histology analysis is highly observer dependent. The normalized cerebral weight method, however, reveals a significant effect between the edematous and nonedematous cases when classifying according to the gold standard. Therefore, we suggest to apply this method for the assessment of brain edema since it is objective and rater independent. Nevertheless, the exact evaluation of brain edema remains a challenging task, especially due to the continuous transition between no edema and edema.

12.
Internet Interv ; 24: 100376, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33718002

RESUMEN

BACKGROUND AND OBJECTIVE: Pain spans a broad spectrum of diseases and types that are highly prevalent and cause substantial disease burden for individuals and society. Up to 40% of people affected by pain receive no or inadequate treatment. Providing a scalable, time-, and location-independent way for pain diagnostic, management, prevention and treatment mobile health applications (MHA) might be a promising approach to improve health care for pain. However, the commercial app market is rapidly growing and unregulated, resulting in an opaque market. Studies investigating the content, privacy and security features, quality and scientific evidence of the available apps are highly needed, to guide patients and clinicians to high quality MHA.Contributing to this challenge, the present study investigates the content, quality, and privacy features of pain apps available in the European app stores. METHODS: An automated search engine was used to identify pain apps in the European Google Play and Apple App store. Pain apps were screened and checked for systematic criteria (pain-relatedness, functionality, availability, independent usability, English or German). Content, quality and privacy features were assessed by two independent reviewers using the German Mobile Application Rating Scale (MARS-G). The MARS-G assesses quality on four objectives (engagement, functionality, aesthetics, information quality) and two subjective scales (perceived impact, subjective quality). RESULTS: Out of 1034 identified pain apps 218 were included. Pain apps covered eight different pain types. Content included basic information, advice, assessment and tracking, and stand-alone interventions. The overall quality of the pain apps was average M = 3.13 (SD = 0.56, min = 1, max = 4.69). The effectiveness of less than 1% of the included pain apps was evaluated in a randomized controlled trial. Major problems with data privacy were present: 59% provided no imprint, 70% had no visible privacy policy. CONCLUSION: A multitude of pain apps is available. Most MHA lack scientific evaluation and have serious privacy issues, posing a potential threat to users. Further research on evidence and improvements privacy and security are needed. Overall, the potential of pain apps is not exploited.

13.
CBE Life Sci Educ ; 19(2): es4, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32453678

RESUMEN

Visual representations, such as pathway models, are increasingly being used to both communicate higher education science, technology, engineering, and mathematics (STEM) education program evaluation plans as well as accurately represent complex programs and the systems within which the educational programs reside. However, these representations can be overwhelming to audiences that are not familiar with the program's structure or engaged in the evaluation process. The goal of this methods essay is to help both evaluators and discipline-based education researchers improve communication about program evaluation with a variety of stakeholders. We propose a three-stage method for developing progressively less complex visualizations to build affordances that help make the program evaluation process and statements of program impact more meaningful to a wider range of audiences. The creation of less complex visualizations can facilitate understanding by allowing a stakeholder to more easily "see" the structure of the program and thereby may evoke a greater willingness to take action and make meaningful programmatic changes based on strategic evaluation planning. To aid readers, we describe how we modified the Systems Evaluation Protocol (SEP) to develop simplified visualizations when evaluating a long-standing college science faculty development program, the Summer Institutes on Scientific Teaching.


Asunto(s)
Ingeniería , Evaluación de Programas y Proyectos de Salud , Tecnología , Docentes , Humanos , Matemática , Desarrollo de Programa
14.
Forensic Sci Int ; 308: 110164, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32014814

RESUMEN

While cerebral edema is a live-threatening condition in living persons, also an edema-like fluid redistribution can occur post mortem. In deceased, usually macroscopic signs are evaluated during autopsy in order to determine the presence or absence of cerebral edema. As a quantitative and objective classification is beneficial, an already existing method (Radojevic et al., 2017), which is based on a mathematical formula using the intracranial dimensions and the cerebral weight, was compared to the evaluation of macroscopic signs in 31 cases. The results showed an excellent agreement for the comparison between the raters as well as the measurement methods (at opened skull or in CT images). However, both measurement methods only poorly agree with the macroscopic edema evaluation. In order to find a more concordant method, the normalized cerebral weight, which puts the cerebral weight in relation to the intracranial volume, was calculated for 115 cases. This method resulted in an excellent agreement with the macroscopic rating and showed a clear numerical difference between the edematous and nonedematous group. While the influence of the post mortem time and the cooling time was found to be negligible, the age at death might confound the edema classification due to pre-existing cerebral atrophy leading to lower cerebral weights. In summary, the present study compared different assessment methods to classify cerebral edema and developed a rater independent, objective and quantitative classification method, which was as reliable as the rating of the forensic pathologists.


Asunto(s)
Autopsia/métodos , Edema Encefálico/patología , Patologia Forense , Cambios Post Mortem , Adulto , Anciano , Anciano de 80 o más Años , Pesos y Medidas Corporales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Teóricos , Reproducibilidad de los Resultados , Adulto Joven
15.
Acta Biomater ; 102: 83-99, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31760221

RESUMEN

The mechanical properties of the stomach wall help to explain its function of storing, mixing, and emptying in health and disease. However, much remains unknown about its mechanical properties, especially regarding regional heterogeneities and wall microstructure. Consequently, the present study aimed to assess regional differences in the mechanical properties and microstructure of the stomach wall. In general, the stomach wall and the different tissue layers exhibited a nonlinear stress-stretch relationship. Regional differences were found in the mechanical response and the microstructure. The highest stresses of the entire stomach wall in longitudinal direction were found in the corpus (201.5 kPa), where food is ground followed by the antrum (73.1 kPa) and the fundus (26.6 kPa). In contrast, the maximum stresses in circumferential direction were 39.7 kPa, 26.2 kPa, and 15.7 kPa for the antrum, fundus, and corpus, respectively. Independent of the fibre orientation and with respect to the biaxial loading direction, partially clear anisotropic responses were detected in the intact wall and the muscular layer. In contrast, the innermost mucosal layer featured isotropic mechanical characteristics. Pronounced layers of circumferential and longitudinal muscle fibres were found in the fundus only, whereas corpus and antrum contained almost exclusively circumferential orientated muscle fibres. This specific stomach structure mirrors functional differences in the fundus as well as corpus and antrum. Within this study, the load transfer mechanisms, connected with these wavy layers but also in total with the stomach wall's microstructure, are discussed. STATEMENT OF SIGNIFICANCE: This article examines for the first time the layer-specific mechanical and histological properties of the stomach wall attending to the location of the sample. Moreover, both mechanical behaviour and microstructure were explicitly match identifying the heterogeneous characteristics of the stomach. On the one hand, the results of this study contribute to the understanding of stomach mechanics and thus to their functional understanding of stomach motility. On the other hand, they are relevant to the fields of constitutive formulation of stomach tissue, whole stomach mechanics, and stomach-derived scaffolds i.e., tissue-engineering grafts.


Asunto(s)
Estómago/fisiología , Animales , Fenómenos Biomecánicos , Pruebas Mecánicas , Modelos Biológicos , Músculo Liso/anatomía & histología , Estómago/ultraestructura , Estrés Mecánico , Porcinos
16.
Oncotarget ; 7(4): 3897-904, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26684029

RESUMEN

Prostate cancer is notorious for its heterogeneity, which poses a problem for the applicability of diagnostic molecular markers. However, heterogeneity analysis can provide valuable information on the chronology in which molecular alterations arise. Here, we constructed a heterogeneity tissue microarray (TMA) comprising samples from 10 different tumor areas of 189 prostate cancers each in order to study the sequence of two frequent molecular alterations, i.e. 6q15 deletion and TMPRSS2:ERG fusion. Previous work shows a marked inverse relationship between these alterations, suggesting that presence of one of these alterations might impact development of the other. 6q15 deletion was analyzed by fluorescence in situ hybridization and ERG-expression by immunohistochemistry. Only 6.6% of 334 ERG-positive but 28.4% of 440 ERG-negative TMA spots showed 6q15 deletions (p < 0.0001). A breakdown of these data to the level of tumor foci revealed 6q deletions in 138 tumor foci that were large enough to have at least 3 analyzable TMA spots. These included 42 tumor foci with homogeneous ERG positivity and 16 with homogeneous 6q15 deletions. Remarkably, six of the 42 homogeneously ERG-positive tumor foci (14.3%) harbored small 6q15-deleted areas, but none of the 34 6q15-deleted foci showed areas of ERG positivity (p = 0.022). In conclusion, our data suggest that ERG-fusion can precede 6q15 deletion, but not vice versa. The complete absence of ERG-positive tumor areas in 6q15-deleted tumor foci further suggest that the functional consequences of 6q15 deletions may prevent the development of TMPRSS2:ERG fusions.


Asunto(s)
Adenocarcinoma/genética , Cromosomas Humanos Par 6/genética , Eliminación de Gen , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Próstata/genética , Transactivadores/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundario , Anciano , Anciano de 80 o más Años , Humanos , Técnicas para Inmunoenzimas , Hibridación Fluorescente in Situ , Metástasis Linfática , Quinasas Quinasa Quinasa PAM/metabolismo , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Análisis de Matrices Tisulares , Regulador Transcripcional ERG
17.
Mod Pathol ; 27(12): 1612-20, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24762546

RESUMEN

TMPRSS2:ERG fusions, in combination with deletion of the phosphatase and tensin homolog (PTEN) tumor suppressor, have been suggested to cooperatively drive tumor progression in prostate cancer. We utilized a novel heterogeneity tissue microarray containing samples from 10 different tumor blocks of 189 prostatectomy specimens to study heterogeneity of genomic PTEN alterations in individual foci. PTEN alterations were found in 48/123 (39%) analyzable individual tumor foci, including 40 foci with deletions, 7 with deletion and rearrangement, and 1 focus with rearrangement only. PTEN was homogeneously aberrant in only 4 (8%) and heterogeneously in 44 (92%) of the foci. We found a specific sequence of molecular events from PTEN breakage followed by deletion of DNA sequences flanking the breakpoint, resulting in homozygous deletion. The observation that 16 of 19 foci with homogeneous ERG positivity had focal PTEN alterations but none of 10 foci with PTEN alterations had focal ERG positivity (P<0.0001) suggests that PTEN alterations typically develop subsequent to ERG fusions. We demonstrate a high level of intratumoral heterogeneity of PTEN alterations with deletions and rearrangements that challenges potential PTEN routine diagnosis testing in biopsies. The observation that PTEN alterations develop subsequent to ERG fusion strongly suggests that ERG expression may directly drive development of PTEN aberrations.


Asunto(s)
Adenocarcinoma/genética , Proteínas de Fusión Oncogénica/genética , Fosfohidrolasa PTEN/genética , Neoplasias de la Próstata/genética , Transactivadores/genética , Eliminación de Gen , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Masculino , Análisis de Matrices Tisulares , Regulador Transcripcional ERG
18.
Mod Pathol ; 26(1): 106-16, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22899295

RESUMEN

Approximately 50% of prostate cancers are characterized by TMPRSS2 (transmembrane protease serine 2)-ERG (avian v-ets erythroblastosis virus E26 oncogene homolog) gene fusions resulting in an androgen-regulated overexpression of the transcription factor ERG. Some studies have suggested prognostic or predictive relevance of ERG status in prostate cancer. Such concepts could be impaired by extensive ERG heterogeneity in analyzed tumors. The aim of this study was to analyze the extent of heterogeneity for TMPRSS2-ERG fusion in prostate cancer. To enable large-scale studies on the extent of heterogeneity of biomarkers in prostate cancer, a heterogeneity tissue microarray containing samples from 10 different tumor blocks of 190 large prostate cancers selected from a consecutive series of 480 radical prostatectomies was developed. ERG expression was analyzed by immunohistochemistry. Positive ERG immunostaining was found in arrayed cancer-containing samples from 103 of the 178 analyzable patients (58%). ERG immunostaining was homogeneously positive in 29 prostate cancers (16%), whereas heterogeneous ERG positivity was seen in 74 cancers (42%). ERG heterogeneity was within one tumor focus (intrafocal heterogeneity) in 69 cases (93% of heterogeneous cases) and between different tumor foci (interfocal heterogeneity) in 5 cases (7%). Marked intrafocal heterogeneity challenges the concept of TMPRSS2-ERG fusion always representing an early step in prostate cancer development. Marked heterogeneity also compromises the concept of analyzing ERG status for treatment decisions in diagnostic needle core biopsies.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Próstata/metabolismo , Transactivadores/biosíntesis , Adulto , Anciano , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Proteínas de Fusión Oncogénica/análisis , Proteínas de Fusión Oncogénica/biosíntesis , Neoplasias de la Próstata/patología , Análisis de Matrices Tisulares , Transactivadores/análisis , Regulador Transcripcional ERG
19.
Environ Sci Pollut Res Int ; 14(6): 435-42, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17993228

RESUMEN

BACKGROUND: In the Aral Sea basin, safe water resources are scarce and steadily becoming scarcer. Particularly high quality water is going to become a rare good. The object of the study was the Tuyamuyun Hydroengineering Complex (THC), a complex of artificial water reservoirs located in the lower Amu Darya River, which provides water for irrigation, industry, and drinking for the lower Amu Darya region. The focus was on operation of one of its four reservoirs, the Kaparas, which is mainly used for drinking water supply. The objective includes the investigation of impacts of conventional operation schemes on the reservoir water quality for improving drinking water quality (salinity). Basic operation rules for Kaparas, which can be considered as representative for conventional dam operation under dry year conditions, had to be identified and improved operation schemes derived. METHODS: Existing data archives were analysed, and further data were acquired from field surveys, data processing and modelling studies. Historical data were identified, which are appropriate to determine representative schemes for the conventional operation. For the simulation of time-dependent and depth-dependent changes of reservoir salinisation, the reservoir water quality model Lac was used and linked with the THC model. RESULTS AND DISCUSSION: Modelling results for the simulation of temperature dynamics and density stratification showed a sufficient congruence with the measured temperature profiles. The conformity of measured and calculated salt concentration is basically ensured. The reservoir, which fill with higher saline water at the end of the summer, aggravates the entrainment of high saline water in the entire water column. CONCLUSIONS: The current conventional operation regime mainly leads to filling the Kaparas reservoir with high saline water during the winter months. Even in the event of starting with comparable low salinity levels, the simulation demonstrates the rapid deterioration of the reservoir water quality. Under dry year conditions, the WHO standards for drinking water will be exceeded by 30% after two years, so that the impact of dry years in the context of water stress becomes visible. RECOMMENDATIONS AND OUTLOOK: Processed data and results are now available to identify enhanced reservoir operation strategies for salinity reduction by changing the period of reservoir filling and release, as well as to initiate a detailed analysis of how water deficits in dry years may be reduced by improved operation regimes. Using adapted and enhanced operation rules for THC reservoirs, the local population within the lower Aral Sea basin might be supplied with more potable water of higher quality in future.


Asunto(s)
Abastecimiento de Agua/normas , Agua/química , Monitoreo del Ambiente , Ríos , Cloruro de Sodio/análisis , Factores de Tiempo , Uzbekistán , Contaminantes Químicos del Agua/análisis
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