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Tumor hypoxia is a negative prognostic factor in many tumors and is predictive of metastatic spread and poor responsiveness to both chemotherapy and radiotherapy. Purpose: To assess the feasibility of using 18F-Fluoroazomycin arabinoside (FAZA) PET/MR to image tumor hypoxia in patients with locally advanced rectal cancer (LARC) prior to and following neoadjuvant chemoradiotherapy (nCRT). The secondary objective was to compare different reference tissues and thresholds for tumor hypoxia quantification. Patients and Methods: Eight patients with histologically proven LARC were included. All patients underwent 18F-FAZA PET/MR prior to initiation of nCRT, four of whom also had a second scan following completion of nCRT and prior to surgery. Tumors were segmented using T2-weighted MR. Each voxel within the segmented tumor was defined as hypoxic or oxic using thresholds derived from various references: ×1.0 or ×1.2 SUVmean of blood pool [BP] or left ventricle [LV] and SUVmean +3SD for gluteus maximus. Correlation coefficient (CoC) between HF and tumor SUVmax/reference SUVmean TRR for the various thresholds was calculated. Hypoxic fraction (HF), defined as the % hypoxic voxels within the tumor volume was calculated for each reference/threshold. Results: For all cases, baseline and follow-up, the CoCs for gluteus maximus and for BP and LV (×1.0) were 0.241, 0.344, and 0.499, respectively, and HFs were (median; range) 16.6% (2.4–33.8), 36.8% (0.3–72.9), and 30.7% (0.8–55.5), respectively. For a threshold of ×1.2, the CoCs for BP and LV as references were 0.611 and 0.838, respectively, and HFs were (median; range) 10.4% (0–47.6), and 4.3% (0–20.1%), respectively. The change in HF following nCRT ranged from (−18.9%) to (+54%). Conclusions: Imaging of hypoxia in LARC with 18F-FAZA PET/MR is feasible. Blood pool as measured in the LV appears to be the most reliable reference for calculating the HF. There is a wide range of HF and variable change in HF before and after nCRT.

This study aimed to compare the detection of neuroendocrine tumor liver metastases (NLMs) in hepatobiliary-specific contrast-enhanced MRI (pMR) versus 68Ga-DOTATATE PET/CT (DT-PET). This retrospective study cohort included 30 patients with well-differentiated neuroendocrine tumors who underwent both DT-PET and pMR. Two readers independently assessed NLMs count, SUVmax on DT-PET, and signal characteristics on pMR. A consensus review by two additional readers resolved discrepancies between the modalities. Results showed concordance between DT-PET and pMR NLM count in 14/30 patients (47%). pMR identified more NLMs in 12/30 patients (40%), of which 4 patients showed multiple deposits on pMR but only 0–1 lesions on DT-PET. DT-PET detected more in 4/30 patients (13%). Overall, pMR detected more metastases than DT-PET (p = 0.01). Excluding the four outliers, there was excellent agreement between the two methods (ICC: 0.945, 95%CI: 0.930, 0.958). Notably, pMR had a higher NLM detection rate than DT-PET, with correlations found between lesion size on pMR and DT-PET detectability, as well as diffusion restriction on pMR and SUVmax on DT-PET. In conclusion, in consecutive patients with well-differentiated NETs, the detection rate of NLM is higher with pMR than with DT-PET. However, when excluding patients whose tumors do not overexpress somatostatin receptors (13% of the cohort), high concordance in the detection of NLM is observed between DT PET and pMR.

We aimed to determine if clinical parameters and radiomics combined with sarcopenia status derived from baseline 18F-FDG-PET/CT could predict developing metastatic disease and overall survival (OS) in gastroesophageal cancer (GEC). Patients referred for primary staging who underwent 18F-FDG-PET/CT from 2008 to 2019 were evaluated retrospectively. Overall, 243 GEC patients (mean age = 64) were enrolled. Clinical, histopathology, and sarcopenia data were obtained, and primary tumor radiomics features were extracted. For classification (early-stage vs. advanced disease), the association of the studied parameters was evaluated. Various clinical and radiomics models were developed and assessed. Accuracy and area under the curve (AUC) were calculated. For OS prediction, univariable and multivariable Cox analyses were performed. The best model included PET/CT radiomics features, clinical data, and sarcopenia score (accuracy = 80%; AUC = 88%). For OS prediction, various clinical, CT, and PET features entered the multivariable analysis. Three clinical factors (advanced disease, age ≥ 70 and ECOG ≥ 2), along with one CT-derived and one PET-derived radiomics feature, retained their significance. Overall, 18F-FDG PET/CT radiomics seems to have a potential added value in identifying GEC patients with advanced disease and may enhance the performance of baseline clinical parameters. These features may also have a prognostic value for OS, improving the decision-making for GEC patients.

We aimed to investigate whether [18F]F-FDG-PET/CT-derived radiomics can classify histologic subtypes and determine the anatomical origin of various malignancies. In this IRB-approved retrospective study, 391 patients (age = 66.7 ± 11.2) with pulmonary (n = 142), gastroesophageal (n = 128) and head and neck (n = 121) malignancies were included. Image segmentation and feature extraction were performed semi-automatically. Two models (all possible subset regression [APS] and recursive partitioning) were employed to predict histology (squamous cell carcinoma [SCC; n = 219] vs. adenocarcinoma [AC; n = 172]), the anatomical origin, and histology plus anatomical origin. The recursive partitioning algorithm outperformed APS to determine histology (sensitivity 0.90 vs. 0.73; specificity 0.77 vs. 0.65). The recursive partitioning algorithm also revealed good predictive ability regarding anatomical origin. Particularly, pulmonary malignancies were identified with high accuracy (sensitivity 0.93; specificity 0.98). Finally, a model for the synchronous prediction of histology and anatomical disease origin resulted in high accuracy in determining gastroesophageal AC (sensitivity 0.88; specificity 0.92), pulmonary AC (sensitivity 0.89; specificity 0.88) and head and neck SCC (sensitivity 0.91; specificity 0.92). Adding PET-features was associated with marginal incremental value for both the prediction of histology and origin in the APS model. Overall, our study demonstrated a good predictive ability to determine patients’ histology and anatomical origin using [18F]F-FDG-PET/CT-derived radiomics features, mainly from CT.

The COVID-19 pandemic evolves constantly, requiring adaptable solutions to combat emerging SARS-CoV-2 variants. To address this, we created a pentameric scaffold based on a mammalian protein, which can be customized with up to 10 protein binding modules. This molecular scaffold spans roughly 20 nm and can simultaneously neutralize SARS-CoV-2 Spike proteins from one or multiple viral particles. Using only two different modules targeting the Spike’s RBD domain, this construct outcompetes human antibodies from vaccinated individuals’ serum and blocks in vitro cell attachment and pseudotyped virus entry. Additionally, the multibodies inhibit viral replication at low picomolar concentrations, regardless of the variant. This customizable multibody can be easily produced in procaryote systems, providing a new avenue for therapeutic development and detection devices, and contributing to preparedness against rapidly evolving pathogens.

To assess the impact of the COVID-19 pandemic on the diagnosis, staging and outcome of a selected population throughout the first two years of the pandemic, we evaluated oncology patients undergoing PET/CT at our institution. A retrospective population of lung cancer, melanoma, lymphoma and head and neck cancer patients staged using PET/CT during the first 6 months of the years 2019, 2020 and 2021 were included for analysis. The year in which the PET was performed was our exposure variable, and our two main outcomes were stage at the time of the PET/CT and overall survival (OS). A total of 1572 PET/CTs were performed for staging purposes during the first 6 months of 2019, 2020 and 2021. The median age was 66 (IQR 16), and 915 (58%) were males. The most prevalent staged cancer was lung cancer (643, 41%). The univariate analysis of staging at PET/CT and OS by year of PET/CT were not significantly different. The multivariate Cox regression of non-COVID-19 significantly different variables at univariate analysis and the year of PET/CT determined that lung cancer (HR 1.76 CI95 1.23–2.53, p < 0.05), stage III (HR 3.63 CI95 2.21–5.98, p < 0.05), stage IV (HR 11.06 CI95 7.04–17.36, p < 0.05) and age at diagnosis (HR 1.04 CI95 1.02–1.05, p < 0.05) had increased risks of death. We did not find significantly higher stages or reduced OS when assessing the year PET/CT was performed. Furthermore, OS was not significantly modified by the year patients were staged, even when controlled for non-COVID-19 significant variables (age, type of cancer, stage and gender).

The imaging report is essential for the communication between physicians in patient care. The information it contains must be clear, concise with evidence-based conclusions and sufficient to support clinical decision-making. In recent years, several classification schemes and/or reporting guidelines for PET have been introduced. In this manuscript, we will review the classifications most frequently used in oncology for interpreting and reporting 18F-FDG PET imaging in lymphoma, multiple myeloma, melanoma and head and neck cancers, PSMA-ligand PET imaging for prostate cancer, and 68Ga-DOTA-peptide PET in neuroendocrine tumors (NET).

Purpose: To describe the initial experience of an academic center using 18F-DCFPyL PET in managing men with recurrent prostate cancer. Materials & Methods: This prospective, single-arm IRB-approved study included men with biochemical failure after primary therapy for prostate cancer and negative/equivocal CT and bone scintigraphy who were candidates for salvage therapy, as determined by a multidisciplinary panel of experts. 18F-DCFPyL PET was assessed for the presence and extent of recurrence: local, oligometastatic (≤4), or extensive. Post-PET management and clinical outcome, including PSA response, was documented. For patients who received PET-directed ablative therapies, response was categorized as “complete” if PSA became undetectable or “favorable” if PSA decreased ≥50%. Results: Forty-seven men with biochemical failure after radical prostatectomy (n = 29), primary radiotherapy (n = 15) or focal tumor ablation (n = 3) were included. PET was positive in (43/47) 91.5%, including local recurrence in (9/47) 19.2%; oligometastatic disease in (16/47) 34%; and extensive metastatic disease in (18/47) 38.3%. PET-directed focal ablative therapies without systemic therapy were given to (13/29) 44.8% of patients without extensive metastases on PET with a mean PSA response of 69% (median, 74.5%; range: 35–100). Favorable biochemical response was observed in (10/13) 76.9% of patients with limited recurrence on PET, and in 23.1% (3/13), there was complete response. Conclusion: 18F-DCFPyL PET was positive in >90% of patients with biochemical failure. For those with limited recurrence, PSMA PET-directed local ablative therapies resulted in favorable outcome in more than 3 in 4 patients, and in nearly a quarter of them, there was complete biochemical response.

PurposeRadiomics is an emerging imaging assessment technique that has shown promise in predicting survival among nasopharyngeal carcinoma (NPC) patients. Studies so far have focused on PET or MR-based radiomics independently. The aim of our study was to evaluate the prognostic value of clinical and radiomic parameters derived from both PET/CT and MR.MethodsRetrospective evaluation of 124 NPC patients with PET/CT and radiotherapy planning MR (RP-MR). Primary tumors were segmented using dedicated software (LIFEx version 6.1) from PET, CT, contrast-enhanced T1-weighted (T1-w), and T2-weighted (T2-w) MR sequences with 376 radiomic features extracted. Summary statistics describe patient, disease, and treatment characteristics. The Kaplan–Meier (KM) method estimates overall survival (OS) and progression-free survival (PFS). Clinical factors selected based on univariable analysis and the multivariable Cox model were subsequently constructed with radiomic features added.ResultsThe final models comparing clinical, clinical + RP-MR, clinical + PET/CT and clinical + RP-MR + PET/CT for OS and PFS demonstrated that combined radiomic signatures were significantly associated with improved survival prognostication (AUC 0.62 vs 0.81 vs 0.75 vs 0.86 at 21 months for PFS and 0.56 vs 0.85 vs 0.79 vs 0.96 at 24 months for OS). Clinical + RP-MR features initially outperform clinical + PET/CT for both OS and PFS (42 months).ConclusionOur study demonstrated that PET/CT-based radiomic features may improve survival prognostication among NPC patients when combined with baseline clinical and MR-based radiomic features.

Objetivo: el objetivo principal de este trabajo es analizar el contenido que las marcas más vendidas del sector automovilístico en España en el año 2019 están difundiendo en sus canales propios en YouTube. Diseño/metodología/enfoque: se sigue la metodología de análisis de contenido para analizar los vídeos más populares de las diez marcas de coches utilitarias más vendidas en el año 2019 en España. Para ello se identifica, en primer lugar, el canal, suscriptores y los vídeos más visualizados desde finales de 2018 y a lo largo de 2019. En segundo lugar, se analiza el contenido de los mensajes y, por último, la interacción de los públicos a través del número de «me gusta» que ha recibido cada uno de los videos analizados. Resultados: los resultados han permitido entender qué contenido están difundiendo las marcas de automóviles a través de sus canales propios de YouTube en un periodo concreto. Además, de poner de manifiesto que, aunque el contenido más habitual sea el clásico spot publicitario que las marcas utilizan para televisión y otros medios convencionales, también se ha desvelado la utilización de YouTube para apoyar la estrategia de Inbound marketing. Limitaciones/implicaciones: se trata de una investigación descriptiva, cuyo alcance es exploratorio, por lo que su principal aportación es una revisión novedosa sobre el objeto de estudio que supone un punto de partida para investigaciones posteriores. Asimismo, dada la limitada muestra, 50 videos, y que los datos obtenidos a través del análisis se han acotado a un periodo de tiempo concreto, los resultados no se pueden generalizar, pero sí permiten abrir una reflexión acerca del uso de los canales propios de YouTube por parte de las marcas del sector del automóvil. Originalidad/contribución: la originalidad de este estudio radica en el estudio de un sector en concreto, el automovilístico, y por su relevancia como anunciante y como sector empresarial.

Purpose: The aim of the study is to evaluate the prognostic value of a joint evaluation of PET and CT radiomics combined with standard clinical parameters in patients with HL. Methods: Overall, 88 patients (42 female and 46 male) with a median age of 43.3 (range 21–85 years) were included. Textural analysis of the PET/CT images was performed using freely available software (LIFE X). 65 radiomic features (RF) were evaluated. Univariate and multivariate models were used to determine the value of clinical characteristics and FDG PET/CT radiomics in outcome prediction. In addition, a binary logistic regression model was used to determine potential predictors for radiotherapy treatment and odds ratios (OR), with 95% confidence intervals (CI) reported. Features relevant to survival outcomes were assessed using Cox proportional hazards to calculate hazard ratios with 95% CI. Results: albumin (p = 0.034) + ALP (p = 0.028) + CT radiomic feature GLRLM GLNU mean (p = 0.012) (Area under the curve (AUC): 95% CI (86.9; 100.0)—Brier score: 3.9, 95% CI (0.1; 7.8) remained significant independent predictors for PFS outcome. PET-SHAPE Sphericity (p = 0.033); CT grey-level zone length matrix with high gray-level zone emphasis (GLZLM SZHGE mean (p = 0.028)); PARAMS XSpatial Resampling (p = 0.0091) as well as hemoglobin results (p = 0.016) remained as independent factors in the final model for a binary outcome as predictors of the need for radiotherapy (AUC = 0.79). Conclusion: We evaluated the value of baseline clinical parameters as well as combined PET and CT radiomics in HL patients for survival and the prediction of the need for radiotherapy treatment. We found that different combinations of all three factors/features were independently predictive of the here evaluated endpoints.

Lung cancer remains the leading cancer-related death across North America. Imaging is fundamental. Recently, healthcare disparities came into research focus. Our aim was to explore disparity from an imaging, genetic, and outcome perspective. We utilized the AACR Project GENIE Biopharma Consortium (BPC) dataset v 1.1 to build a collated NSCLC dataset. Descriptive and analytical statistics were applied according to data characteristics. From 1849 patients, mean age was 64.4 y (±10.5), 58% (n = 1065) were female, 23% (n = 419) never smoked, 84% (n = 1545) were of white race, and 57% (n = 1052) were < stage III. No difference (p > 0.05) was found for baseline imaging by race. White race showed higher 3-month surveillance imaging (p = 0.048) and a baseline stage < IV (OR 0.61). KRAS (33.3 vs. 17.9%), STK11 (14.8 vs. 7.3%), and KEAP1 (13.3 vs. 5.3%) mutations were predominant among white patients while EGFR mutation (19.2 vs. 44.1%) was less predominant. Mutations in TP53 or KEAP1 had worse PFS and OS. The latter was also reduced in STK11, KRAS + STK11, and KRAS + KEAP1 mutations. Meanwhile, EGFR mutation had increased OS. Multivariate analysis showed that progression on imaging at 3 or 6 months (HR 1.69 and 1.43, respectively), TP53 (HR 1.37) and KRAS (HR 1.26) had lower OS while EGFR and LRP1B (HR 0.69 and 0.39, respectively) had higher OS. No racial disparity at baseline imaging was observed. Higher initial stages among non-white patients might reflect inequalities in accessing healthcare. However, race wasn’t associated to OS. Finally, progression in imaging at 3 or 6 months showed the higher hazard ratios for death.

We investigated the prognostic value of sarcopenia measurements and metabolic parameters of primary tumors derived from 18F-FDG-PET/CT among patients with primary, metastatic esophageal and gastroesophageal cancer. A total of 128 patients (26 females; 102 males; mean age 63.5 ± 11.7 years; age range: 29–91 years) with advanced metastatic gastroesophageal cancer who underwent 18F-FDG-PET/CT as part of their initial staging between November 2008 and December 2019 were included. Mean and maximum standardized uptake value (SUV) and SUV normalized by lean body mass (SUL) were measured. Skeletal muscle index (SMI) was measured at the level of L3 on the CT component of the 18F-FDG-PET/CT. Sarcopenia was defined as SMI < 34.4 cm2/m2 in women and 2/m2 in men. A total of 60/128 patients (47%) had sarcopenia on baseline 18F-FDG-PET/CT. Mean SMI in patients with sarcopenia was 29.7 cm2/m2 in females and 37.5 cm2/m2 in males. In a univariable analysis, ECOG (p = 0.028), SMI (p = 0.0075) and dichotomized sarcopenia score (p = 0.033) were significant prognostic factors for overall survival (OS) and progression-free survival (PFS). Age was a poor prognostic factor for OS (p = 0.017). Standard metabolic parameters were not statistically significant in the univariable analysis and thus were not evaluated further. In a multivariable analysis, ECOG (p < 0.001) and bone metastases (p = 0.019) remained significant poor prognostic factors for OS and PFS. The final model demonstrated improved OS and PFS prognostication when combining clinical parameters with imaging-derived sarcopenia measurements but not metabolic tumor parameters. In summary, the combination of clinical parameters and sarcopenia status, but not standard metabolic values from 18F-FDG-PET/CT, may improve survival prognostication in patients with advanced, metastatic gastroesophageal cancer.

Abstract Goal PET is a relatively noisy process compared to other imaging modalities, and sparsity of acquisition data leads to noise in the images. Recent work has focused on machine learning techniques to improve PET images, and this study investigates a deep learning approach to improve the quality of reconstructed image volumes through denoising by a 3D convolution neural network. Potential improvements were evaluated within a clinical context by physician performance in a reading task. Methods A wide range of controlled noise levels was emulated from a set of chest PET data in patients with lung cancer, and a convolutional neural network was trained to denoise the reconstructed images using the full-count reconstructions as the ground truth. The benefits, over conventional Gaussian smoothing, were quantified across all noise levels by observer performance in an image ranking and lesion detection task. Results The CNN-denoised images were generally ranked by the physicians equal to or better than the Gaussian-smoothed images for all count levels, with the largest effects observed in the lowest-count image sets. For the CNN-denoised images, overall lesion contrast recovery was 60% and 90% at the 1 and 20 million count levels, respectively. Notwithstanding the reduced lesion contrast recovery in noisy data, the CNN-denoised images also yielded better lesion detectability in low count levels. For example, at 1 million true counts, the average true positive detection rate was around 40% for the CNN-denoised images and 30% for the smoothed images. Conclusion Significant improvements were found for CNN-denoising for very noisy images, and to some degree for all noise levels. The technique presented here offered however limited benefit for detection performance for images at the count levels routinely encountered in the clinic.

We investigate whether computed tomography (CT) derived radiomics may correlate with driver gene mutations in patients with pancreatic ductal adenocarcinoma (PDAC). In this retrospective study, 47 patients (mean age 64 ± 11 years; range: 42–86 years) with PDAC, who were treated surgically and who underwent preoperative CT imaging at our institution were included in the study. Image segmentation and feature extraction was performed semi-automatically with a commonly used open-source software platform. Genomic data from whole genome sequencing (WGS) were collected from our institution’s web-based resource. Two statistical models were then built, in order to evaluate the predictive ability of CT-derived radiomics feature for driver gene mutations in PDAC. 30/47 of all tumor samples harbored 2 or more gene mutations. Overall, 81% of tumor samples demonstrated mutations in KRAS, 68% of samples had alterations in TP53, 26% in SMAD4 and 19% in CDKN2A. Extended statistical analysis revealed acceptable predictive ability for KRAS and TP53 (Youden Index 0.56 and 0.67, respectively) and mild to acceptable predictive signal for SMAD4 and CDKN2A (Youden Index 0.5, respectively). Our study establishes acceptable correlation of radiomics features and driver gene mutations in PDAC, indicating an acceptable prognostication of genomic profiles using CT-derived radiomics. A larger and more homogenous cohort may further enhance the predictive ability.

We investigated, whether 18[18F]-FDG PET/CT-derived radiomics combined with sarcopenia measurements improves survival prognostication among patients with advanced, metastatic gastroesophageal cancer. In our study, 128 consecutive patients with advanced, metastatic esophageal and gastroesophageal cancer (n = 128; 26 females; 102 males; mean age 63.5 ± 11.7 years; age range: 29–91 years) undergoing 18[18F]-FDG PET/CT for staging between November 2008 and December 2019 were included. Segmentation of the primary tumor and radiomics analysis derived from PET and CT images was performed semi-automatically with a commonly used open-source software platform (LIFEX, Version 6.30, lifexsoft.org). Patients’ nutritional status was determined by measuring the skeletal muscle index (SMI) at the level of L3 on the CT component. Univariable and multivariable analyses were performed to establish a survival prediction model including radiomics, clinical data, and SMI score. Univariable Cox proportional hazards model revealed ECOG (p = 0.028) to be significant clinical parameters for overall survival (OS) and progression free survival (PFS). Age (p = 0.017) was an additional prognostic factor for OS. Multivariable analysis showed improved prognostication for overall and progression free survival when adding sarcopenic status, PET and CT radiomics to the model with clinical parameters only. PET and CT radiomics derived from hybrid 18[18F]-FDG PET/CT combined with sarcopenia measurements and clinical parameters may improve survival prediction among patients with advanced, metastatic gastroesophageal cancer.

Purpose: We aim determine the value of PET and CT radiomic parameters on survival with serial follow-up PET/CT in patients with nasopharyngeal carcinoma (NPC) for which curative intent therapy is undertaken. Methods: Patients with NPC and available pre-treatment as well as follow up PET/CT were included from 2005 to 2006 and were followed to 2021. Baseline demographic, radiological and outcome data were collected. Univariable Cox proportional hazard models were used to evaluate features from baseline and follow-up time points, and landmark analyses were performed for each time point. Results: Sixty patients were enrolled, and two-hundred and seventy-eight (278) PET/CT were at baseline and during follow-up. Thirty-eight percent (38%) were female, and sixty-two patients were male. All patients underwent curative radiation or chemoradiation therapy. The median follow-up was 11.72 years (1.26–14.86). Five-year and ten-year overall survivals (OSs) were 80.0% and 66.2%, and progression-free survival (PFS) was 90.0% and 74.4%. Time-dependent modelling suggested that, among others, PET gray-level zone length matrix (GLZLM) gray-level non-uniformity (GLNU) (HR 2.74 95% CI 1.06, 7.05) was significantly associated with OS. Landmark analyses suggested that CT parameters were most predictive at 15 month, whereas PET parameters were most predictive at time points 3, 6, 9 and 15 month. Conclusions: This study with long-term follow up data on NPC suggests that mainly PET-derived radiomic features are predictive for OS but not PFS in a time-dependent evaluation. Furthermore, CT radiomic measures may predict OS and PFS best at initial and long-term follow-up time points and PET measures may be more predictive in the interval. These modalities are commonly used in NPC surveillance, and prospective validation should be considered.

The detection of small molecules in living cells using genetically encoded FRET sensors has revolutionized our understanding of signaling pathways at the sub-cellular level. However, engineering fluorescent proteins and specific binding domains to create new sensors remains challenging because of the difficulties associated with the large size of the polypeptides involved, and their intrinsically huge conformational variability. Indeed, FRET sensors’ design still relies on vague structural notions, and trial and error combinations of linkers and protein modules. We recently designed a FRET sensor for the second messenger cAMP named CUTie (Cyclic nucleotide Universal Tag for imaging experiments), which granted sub-micrometer resolution in living cells. Here we apply a combination of sequence/structure analysis to produce a new-generation FRET sensor for the second messenger cGMP based on Protein kinase G I (PKGI), which we named CUTie2. Coarse-grained molecular dynamics simulations achieved an exhaustive sampling of the relevant spatio-temporal coordinates providing a quasi-quantitative prediction of the FRET efficiency, as confirmed by in vitro experiments. Moreover, biochemical characterization showed that the cGMP binding module maintains virtually the same affinity and selectivity for its ligand thant the full-length protein. The computational approach proposed here is easily generalizable to other allosteric protein modules, providing a cost effective-strategy for the custom design of FRET sensors.

Dynamic infrared thermography (DIRT) has been used for the preoperative mapping of cutaneous perforators. This technique has shown a positive correlation with intraoperative findings. Our aim was to evaluate the accuracy of perforator mapping with DIRT and augmented reality using a portable projector. For this purpose, three volunteers had both of their anterolateral thighs assessed for the presence and location of cutaneous perforators using DIRT. The obtained image of these “hotspots” was projected back onto the thigh and the presence of Doppler signals within a 10-cm diameter from the midpoint between the lateral patella and the anterior superior iliac spine was assessed using a handheld Doppler device. Hotspots were identified in all six anterolateral thighs and were successfully projected onto the skin. The median number of perforators identified within the area of interest was 5 (range, 3–8) and the median time needed to identify them was 3.5 minutes (range, 3.3–4.0 minutes). Every hotspot was correlated to a Doppler sound signal. In conclusion, augmented reality can be a reliable method for transferring the location of perforators identified by DIRT onto the thigh, facilitating its assessment and yielding a reliable map of potential perforators for flap raising.

Recombinant protein expression has become an invaluable tool in basic and applied research. The accumulated knowledge in this field allowed the expression of thousands of protein targets in a soluble, pure, and homogeneous state, essential for biochemical and structural analyses. A lot of progress has been achieved in the last decades, where challenging proteins were expressed in a soluble manner after evaluating different parameters such as host, strain, and fusion partner or promoter strength, among others. In this regard, we have previously developed a vector suite that allows the evaluation of different promoters and solubility enhancer-proteins, through an easy and efficient cloning strategy. Nonetheless, the proper expression of many targets remains elusive, requiring, for example, the addition of complex post-translation modifications and/or passage through specialized compartments. In order to overcome the limitations found when working with a single subcellular localization and a single host type, we herein expanded our previously developed vector suite to include the evaluation of recombinant protein expression in different cell compartments and cell hosts. In addition, these vectors also allow the assessment of alternative purification strategies for the improvement of target protein yields.

Se presenta un caso clínico de paciente con linfoma no Hodgkin tratado; en control tomográfico habitual se le solicitó PET-CT para complementar su estudio, que demuestra un foco metabólicamente activo en el espesor de músculo aductor izquierdo sin traducción tomográfica evidente. La lesión fue estudiada con ultrasonografia de partes blandas y biopsia dirigida, que resultó positiva para infiltración secundaria por linfoma. Este caso demuestra la utilidad de las técnicas complementarias en el manejo de estos pacientes, en especial la utilidad del PET-CT en el estudio de sitios inhabituales de diseminación. En este examen existe la posibilidad de identificar con precisión la localización de las lesiones mediante la TC complementaria, lo que permite efectuar posteriormente el estudio dirigido.A case report of a patient with treated Non-Hodgkin Lymphoma is presented. In his usual tomographic control patient was requested a PET-CT scan to supplement prior study that showed a metabo-lically active focus on the left adductor muscle without evident tomographic correlation. Lesion underwent both a soft tissue ultrasound study and a directed biopsy, the latter being positive for secondary infiltration by lymphoma. This case has demonstrated the usefulness of applying complementary techniques in the management of these lesions, mainly of PET-CT scans in the study of unusual sites of spread. This combined medical imaging technique allows accurate lesion localization, which in turn permits performance of a subsequent directed study.

La enfermedad de injerto contra huésped es un síndrome que ocurre en pacientes inmuno-deprimidos generalmente post-trasplante de médula ósea, caracterizado en su etapa aguda por manifestaciones dermatológicas, hepáticas y gastrointestinales. El diagnóstico oportuno es fundamental, ya que puede disminuir signi-ficativamente la morbimortalidad. Dentro del diagnóstico diferencial de las manifestaciones gastrointestinales se incluye enterocolitis neutropénica y colitis pseudomembranosa. Mediante tomografía computada, hay signos que apuntan a su diagnóstico, como dilatación focal de asas, y refuerzo significativo de la mucosa enterocólicaGraft versus Host Disease is an entity that occurs after bone marrow transplant, in immunocompromised patients, characterized by dermatologic, hepatic and gastrointestinal manifestations. Morbimortality can be reduced significatively by an accurate and prompt diagnosis. The differential diagnosis includes neutropenic enterocolitis and C. difficile Colitis. Computed tomography can help in the diagnosis, with a constellation of findings as focal dilatation of bowel loops, and significant mucosal enhancement

El fenómeno de invaginación en el adulto es un evento poco frecuente, con una amplia variedad de presentación, que va desde síntomas agudos de obstrucción intestinal, hasta síntomas abdominales crónicos inespecíficos. Puede ocurrir tanto en intestino delgado como colon, siendo frecuente encontrar lesiones orgánicas subyacentes, en su mayoría procesos neoplásicos, tanto benignos como malignos Estos últimos son la etiología principal de invaginaciones en intestino grueso. El diagnóstico se puede realizar de forma confiable con el uso de tomografía computada al identificarse características imagenológicas particulares a esta patología. Reportamos dos casos en pacientes que se presentan con síntomas de obstrucción intestinal, con lesiones subyacentes en ambos casos, un lipoma y una neoplasia malignaIntussusception is an uncommon event in adults, with different clinical presentations, which range from bowel obstruction symptoms to nonspecific abdominal pain. Can occur in the small or large bowel. In adults there is usually an underlying cause, usually benign or malignant neoplasms, being the latter the main cause of this disease in the colon. The diagnosis with CT is usually straightforward, with a very typical appearance. We report two cases of patients with bowel obstruction and diagnosis of intussusception caused by a lipoma and colon cancer respectively

This paper r views the sociotechnical organization of biotechnological research of maize in Mexico. Breaking with three misunderstandings imposed since a long time to the net notion, having to do with actor´s distance, size and number and net´s space, in the text we analyze the sociotechnical organization of maizes biotechnology using a methodological net notion that allows us to explain the type of connection that establishes between the participant actors of technical phenomena, al well as their grade of connection (intensity) and their time-relation (stability). The results of the methodological net notion applied in 6 laboratories where biotechnology applied to maize in the country; show that the biotechnology research of Mexican´s maize is not affiliated to maize´s object. None the less, there are different models of research organization of maize´s biotechnology that correspond to particular situations defined by the disposition of social, material and symbolic aspects of research´s groups.

El presente artículo presenta la construcción sociotécnica de dos experiencias de investigación: polímeros cerámicas y papas transgénicas. Ambas tienen por objeto constituirse en una alternativa de análisis a los estudios que resaltan el papel fundamental de la tecnología en la explicación de la globalización. El trabajo muestra dos etnografías de laboratorio. En el caso de los polímeros se muestra cómo la construcción de un saber lo cal se expande internacionalmente; en el segundo, las papas transgénicas, siendo un saber que ha comenzado a ser conocido mundialmente, es necesario situarlo localmente en su proceso de investigación.

La listeriosis es un enfermedad bacteriana poco frecuente con una susceptibilidad mayor por mujeres embarazadas y especialmente por la unidad feto-placentaria. A continuación presentamos un caso ocurrido en el Hospital Central de la Policía, en que se logró confirmar el diagnóstico. Se reviso el tema y se estableció la diferencia en lo que respecta al manejo de este y otro tipo de corioamnionitis.

La enfermedad de injerto contra huésped es un síndrome que ocurre en pacientes inmuno-deprimidos generalmente post-trasplante de médula ósea, caracterizado en su etapa aguda por manifestaciones dermatológicas, hepáticas y gastrointestinales. El diagnóstico oportuno es fundamental, ya que puede disminuir signi-ficativamente la morbimortalidad. Dentro del diagnóstico diferencial de las manifestaciones gastrointestinales se incluye enterocolitis neutropénica y colitis pseudomembranosa. Mediante tomografía computada, hay signos que apuntan a su diagnóstico, como dilatación focal de asas, y refuerzo significativo de la mucosa enterocólica

El fenómeno de invaginación en el adulto es un evento poco frecuente, con una amplia variedad de presentación, que va desde síntomas agudos de obstrucción intestinal, hasta síntomas abdominales crónicos inespecíficos. Puede ocurrir tanto en intestino delgado como colon, siendo frecuente encontrar lesiones orgánicas subyacentes, en su mayoría procesos neoplásicos, tanto benignos como malignos Estos últimos son la etiología principal de invaginaciones en intestino grueso. El diagnóstico se puede realizar de forma confiable con el uso de tomografía computada al identificarse características imagenológicas particulares a esta patología. Reportamos dos casos en pacientes que se presentan con síntomas de obstrucción intestinal, con lesiones subyacentes en ambos casos, un lipoma y una neoplasia maligna

Se presenta un caso clínico de paciente con linfoma no Hodgkin tratado; en control tomográfico habitual se le solicitó PET-CT para complementar su estudio, que demuestra un foco metabólicamente activo en el espesor de músculo aductor izquierdo sin traducción tomográfica evidente. La lesión fue estudiada con ultrasonografia de partes blandas y biopsia dirigida, que resultó positiva para infiltración secundaria por linfoma. Este caso demuestra la utilidad de las técnicas complementarias en el manejo de estos pacientes, en especial la utilidad del PET-CT en el estudio de sitios inhabituales de diseminación. En este examen existe la posibilidad de identificar con precisión la localización de las lesiones mediante la TC complementaria, lo que permite efectuar posteriormente el estudio dirigido.