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Context. During the commissioning of the James Webb Space Telescope (JWST), the mid-infrared instrument (MIRI) observed NGC 6552 with the MIRI Imager and the Medium-Resolution Spectrograph (MRS). NGC 6552 is an active galactic nucleus (AGN) at a redshift of 0.0266 (DL = 120 Mpc) classified as a Seyfert 2 nucleus in the optical and Compton-thick AGN in the X-ray. Aims. This work exemplifies and demonstrates the MRS capabilities to study the mid-infrared (mid-IR) spectra and characterise the physical conditions and kinematics of the ionised and molecular gas in the nuclear regions of nearby galaxies. Methods. MIRI Imager observations covers the full NGC 6552 galaxy at 5.6 µm. MRS observations covers its nuclear region (3.6×4.3 kpc at 17.7–27.9 µm) in a wavelength range between 4.9 and 27.9 µm. These observations were obtained with the aim to investigate the persistence of the MIRI detectors (residual signal left from previous bright source observations). However, NGC 6552 observations demonstrate the performance and power of the MIRI instrument even with a non-optimal observational strategy. Results. We obtained the nuclear, circumnuclear, and central mid-IR spectra of NGC 6552. They provide the first clear observational evidence for a nuclear outflow in NGC 6552. The outflow contributes to 67±7% of the total line flux independent of the ionisation potential (27–187 eV) and critical densities (104–4×106 cm−3 ), showing an average blue-shifted peak velocity of −127±45 km s−1 and an outflow maximal velocity of 698±80 km s−1 . Since the mid-IR photons penetrate dusty regions as efficiently as X-ray keV photons, we interpret these results as the evidence for a highly ionised, non-stratified, AGN-powered, and fast outflowing gas in a low density environment (few 103 cm−3 ) located very close (<0.2 kpc) to the Compton-thick AGN. Nine pure rotational molecular Hydrogen lines are detected and spectrally resolved, and exhibit symmetric Gaussian profiles, consistent with the ga

Context. During the commissioning of the James Webb Space Telescope (JWST), the mid-infrared instrument (MIRI) observed NGC 6552 with the MIRI Imager and the Medium-Resolution Spectrograph (MRS). NGC 6552 is an active galactic nucleus (AGN) at a redshift of 0.0266 (DL = 120 Mpc) classified as a Seyfert 2 nucleus in the optical and Compton-thick AGN in the X-ray. Aims. This work exemplifies and demonstrates the MRS capabilities to study the mid-infrared (mid-IR) spectra and characterise the physical conditions and kinematics of the ionised and molecular gas in the nuclear regions of nearby galaxies. Methods. MIRI Imager observations covers the full NGC 6552 galaxy at 5.6 µm. MRS observations covers its nuclear region (3.6×4.3 kpc at 17.7–27.9 µm) in a wavelength range between 4.9 and 27.9 µm. These observations were obtained with the aim to investigate the persistence of the MIRI detectors (residual signal left from previous bright source observations). However, NGC 6552 observations demonstrate the performance and power of the MIRI instrument even with a non-optimal observational strategy. Results. We obtained the nuclear, circumnuclear, and central mid-IR spectra of NGC 6552. They provide the first clear observational evidence for a nuclear outflow in NGC 6552. The outflow contributes to 67±7% of the total line flux independent of the ionisation potential (27–187 eV) and critical densities (104–4×106 cm−3 ), showing an average blue-shifted peak velocity of −127±45 km s−1 and an outflow maximal velocity of 698±80 km s−1 . Since the mid-IR photons penetrate dusty regions as efficiently as X-ray keV photons, we interpret these results as the evidence for a highly ionised, non-stratified, AGN-powered, and fast outflowing gas in a low density environment (few 103 cm−3 ) located very close (<0.2 kpc) to the Compton-thick AGN. Nine pure rotational molecular Hydrogen lines are detected and spectrally resolved, and exhibit symmetric Gaussian profiles, consistent with the ga

The Medium-Resolution integral field Spectrometer (MRS) of MIRI on board JWST performs spectroscopy between 5 and 28~$\mu$m. The optics of the MRS introduce substantial distortion, and this needs to be rectified in order to reconstruct the observed astrophysical scene. We use data from the JWST/MIRI commissioning and cycle 1 calibration phase, to derive the MRS geometric distortion and astrometric solution, a critical step in the calibration of MRS data. These solutions come in the form of transform matrices that map the detector pixels to spatial coordinates of a local MRS coordinate system called $\alpha$/$\beta$, to the global JWST observatory coordinates V2/V3. For every MRS spectral band and each slice dispersed on the detector, the transform of detector pixels to $\alpha$/$\beta$ is fit by a two-dimensional polynomial, using a raster of point source observations. A polynomial transform is used to map the coordinates from $\alpha$/$\beta$ to V2/V3. We calibrated the distortion of all 198 discrete slices of the MIRI/MRS IFUs, and derived an updated Field of View (FoV) for each MRS spectral band. The precision of the distortion solution is estimated to be better than one tenth of a spatial resolution element, with a root mean square (rms) of 10 milli-arcsecond (mas) at 5 $\mu$m, to 23 mas at 27 $\mu$m. Finally we find that the wheel positioning repeatability causes an additional astrometric error of rms 30 mas. We have demonstrated the MRS astrometric calibration strategy and analysis enabling the calibration of MRS spectra, a critical step in the data pipeline especially for science with spatially resolved objects. The distortion calibration was folded into the JWST pipeline in Calibration Reference Data System (CRDS) context jwst\_1094.pmap. The distortion calibration precision meets the pre-launch requirement, and the estimated total astrometric uncertainty is 50 mas., Comment: 15 pages, 14 figures. Submitted to Astronomy & Astrophysics

ERIS, the Enhanced Resolution Imager and Spectrograph, is an instrument that both extends and enhances the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It replaces two instruments that were being maintained beyond their operational lifetimes, combines their functionality on a single focus, provides a new wavefront sensing module for natural and laser guide stars that makes use of the Adaptive Optics Facility, and considerably improves on their performance. The observational modes ERIS provides are integral field spectroscopy at 1-2.5 {\mu}m, imaging at 1-5 {\mu}m with several options for high contrast imaging, and longslit spectroscopy at 3-4 {\mu}m, The instrument is installed at the Cassegrain focus of UT4 at the VLT and, following its commissioning during 2022, has been made available to the community., Comment: 20 pages with 29 figures; accepted for A&A (minor changes)

During the commissioning of {\em JWST}, the Medium-Resolution Spectrometer (MRS) on the Mid-Infrared Instrument (MIRI) observed the planetary nebula SMP LMC 058 in the Large Magellanic Cloud. The MRS was designed to provide medium resolution (R = $\lambda$/$\Delta\lambda$) 3D spectroscopy in the whole MIRI range. SMP LMC 058 is the only source observed in {\em JWST} commissioning that is both spatially and spectrally unresolved by the MRS and is a good test of {\em JWST's} capabilities. The new MRS spectra reveal a wealth of emission lines not previously detected in this planetary nebula. From these lines, the spectral resolving power ($\lambda$/$\Delta\lambda$) of the MRS is confirmed to be in the range R $=$ 4000 to 1500, depending on the MRS spectral sub-band. In addition, the spectra confirm that the carbon-rich dust emission is from SiC grains and that there is little to no time evolution of the SiC dust and emission line strengths over a 17-year epoch. These commissioning data reveal the great potential of the MIRI MRS for the study of circumstellar and interstellar material., Comment: 12 pages, 7 figures, 3 tables, accepted MNRAS

Primary melanoma of the duodenum is an extremely rare, aggressive and life-threatening malignant neoplasm. Published data regarding the effectiveness of current treatment strategies is limited, and our knowledge relies mostly on sporadic case reports. The diagnosis of primary duodenal melanoma is challenging and is based on the patient’s medical history and findings from physical examination and radiological and endoscopic imaging as well as proper and careful pathological examinations of the tumor. Despite the many advances in cancer treatment, the prognosis for patients with this type of melanoma remains extremely poor. Delayed diagnosis at advanced disease stage, the general aggressive behavior of this neoplasm, the technical difficulty in achieving complete surgical resection, along with the rich vascular and lymphatic drainage of the intestinal mucosa, all have a negative impact on patients’ outcome. In the present review, we aimed to collect and summarize the currently available data in the literature regarding the pathogenesis, clinical features, diagnosis, management and long-term outcomes of this rare, malignant tumor, in order to expand knowledge of its biological behavior and investigate optimal therapeutic options for these patients. Additionally, we present our experience of a case involving a 73-year-old female with primary duodenal melanoma, who was successfully treated with complete surgical resection. © 2022 The Authors.

The MRS is one of the four observing modes of JWST/MIRI. Using JWST in-flight data of unresolved (point) sources, we can derive the MRS absolute spectral response function (ASRF) starting from raw data. Spectral fringing plays a critical role in the derivation and interpretation of the MRS ASRF. In this paper, we present an alternative way to calibrate the data. Firstly, we aim to derive a fringe correction that accounts for the dependence of the fringe properties on the MIRI pupil illumination and detector pixel sampling of the point spread function. Secondly, we aim to derive the MRS ASRF using an absolute flux calibrator observed across the full 5 to 28 $\mu$m wavelength range of the MRS. Thirdly, we aim to apply the new ASRF to the spectrum of a G dwarf and compare with the output of the JWST/MIRI default data reduction pipeline. Finally, we examine the impact of the different fringe corrections on the detectability of molecular features in the G dwarf and K giant. The absolute flux calibrator HD 163466 (A-star) is used to derive tailored point source fringe flats at each of the default dither locations of the MRS. The fringe-corrected point source integrated spectrum of HD 163466 is used to derive the MRS ASRF using a theoretical model for the stellar continuum. A cross-correlation is run to quantify the uncertainty on the detection of CO, SiO, and OH in the K giant and CO in the G dwarf for different fringe corrections. The point-source-tailored fringe correction and ASRF are found to perform at the same level as the current corrections, beating down the fringe contrast to the sub-percent level, whilst mitigating the alteration of real molecular features. The same tailored solutions can be applied to other MRS unresolved targets. A pointing repeatability issue in the MRS limits the effectiveness of the tailored fringe flats is at short wavelengths., Comment: 17 pages, 15 figures, updated to accepted version (results did not change)

The technological progress in spatial-light modulators (SLM) technology has made it possible to use those devices as programmable active focal-plane phase coronagraphic masks, opening the door to novel versatile and adaptive high-contrast imaging observation strategies. However, the scalar nature of the SLM-induced phase response is a potential hurdle when applying the approach to wideband light, as is typical in astronomical imaging. For the first time, we present laboratory results with broadband light (up to ~12pc bandwidth) for two commercially-available SLM devices used as active focal-plane phase masks in the visible regime (640 nm). It is shown that under ideal or realistic telescope aperture conditions, the contrast performance is negligibly affected in this bandwidth regime, reaching sufficient level for ground-based high-contrast imaging, which is typically dominated by atmospheric residuals., Comment: 15 pages, 5 figures

During the commissioning of the James Webb Space Telescope (JWST), the mid-infrared instrument (MIRI) observed NGC6552 with the MIRI Imager and the medium-resolution spectrograph (MRS). NGC6552 is an active galactic nucleus (AGN) at redshift 0.0266 classified as a Seyfert 2 nucleus in the optical, and Compton-thick AGN in X-rays. This work exemplifies and demonstrates the MRS capabilities to study the mid-infrared (mid-IR) spectra and characterize the physical conditions and kinematics of the ionized and molecular gas in the nuclear regions of nearby galaxies. We obtained the nuclear, circumnuclear, and central mid-IR spectra of NGC6552. They provide the first clear observational evidence for a nuclear outflow in NGC6552. The outflow contributes to 67$\pm$7% of the total line flux independent of the ionization potential (27 to 187 eV) and critical densities (10$^4$ to 4$\times$10$^{6}$ cm$^{-3}$), showing an average blue-shifted peak velocity of -127$\pm$45 kms$^{-1}$ and an outflow maximal velocity of 698$\pm$80 kms$^{-1}$. Since the mid-IR photons penetrate dusty regions as efficiently as X-ray keV photons, we interpret these results as the evidence for a highly ionized, non-stratified, AGN-powered, and fast outflowing gas in a low density environment (few 10$^{3}$ cm$^{-3}$) located very close (<0.2kpc) to the Compton-thick AGN. Nine pure rotational molecular Hydrogen lines are detected and spectrally resolved, and exhibit symmetric Gaussian profiles, consistent with the galactic rotation, and with no evidence of outflowing H$_{2}$ material. We detect a warm H$_{2}$ mass of $1.9\pm1.1\times10^7 M_{\odot}$ in the central region (1.8 kpc in diameter) of the galaxy, with almost 30% of that mass in the circum-nuclear region. Line ratios confirm that NGC6552 has a Seyfert nucleus with a black hole mass estimated in the range of 0.6 to 6 million solar masses., Comment: 13 pages, 5 figures, 5 tables, accepted in A&A

Background: Hyperparathyroidism is an almost universal feature of multiple endocrine neoplasia type 1 syndrome. We present a systematic review and meta-analysis of the postoperative outcomes of patients undergoing initial operative treatment of primary hyperparathyroidism complicating multiple endocrine neoplasia 1. Methods: A comprehensive literature search was performed with a priori defined exclusion criteria for studies comparing total parathyroidectomy, subtotal parathyroidectomy, and less than subtotal parathyroidectomy. Results: Twenty-one studies incorporating 1,131 patients (272 undergoing total parathyroidectomy, 510 subtotal parathyroidectomy, and 349 less than subtotal parathyroidectomy) were identified. Pooled results revealed increased risk for long-term hypoparathyroidism in total parathyroidectomy patients (relative risk 1.61; 95% confidence interval, 1.12−2.31; P =.009) versus those undergoing subtotal parathyroidectomy. In the less than subtotal parathyroidectomy or subtotal parathyroidectomy comparison group, a greater risk for recurrence of hyperparathyroidism (relative risk 1.37; 95% confidence interval, 1.05−1.79; P =.02), persistence of hyperparathyroidism (relative risk 2.26; 95% confidence interval, 1.49−3.41; P =.0001), and reoperation for hyperparathyroidism (relative risk 2.48; 95% confidence interval, 1.65−3.73; P <.0001) was noted for less than subtotal parathyroidectomy patients, albeit with lesser risk for long-term for hypoparathyroidism (relative risk 0.47; 95% confidence interval, 0.29−0.75; P =.002). Conclusion: Subtotal parathyroidectomy compares favorably to total parathyroidectomy, exhibiting similar recurrence and persistence rates with a decreased propensity for long-term postoperative hypoparathyroidism. The benefit of the decreased risk of hypoparathyroidism in less than subtotal parathyroidectomy is negated by the increase in the risk for recurrence, persistence, and reoperation. Future studies evaluating the performanc

The Medium Resolution Spectrometer on board JWST/MIRI will give access to mid-IR spectra while retaining spatial information. With the unparalleled sensitivity of JWST and the MIRI detectors, the MRS has the potential to revolutionise our understanding of giant exoplanet atmospheres. Molecular mapping is a promising detection and characterisation technique used to study the spectra of directly imaged exoplanets. We aim to examine the feasibility and application of this technique to MRS observations. We used the instrument simulator MIRISIM to create mock observations of resolved star and exoplanet systems. As an input for the simulator, we used stellar and planet parameters from literature, with the planet spectrum being modelled with the radiative transfer code petitRADTRANS. After processing the raw data with the JWST pipeline, we high pass filter the data to account for the stellar point spread function, and used a forward modelling approach to detect the companions and constrain the chemical composition of their atmospheres through their molecular signatures. We identified limiting factors in spectroscopic characterisation of directly imaged exoplanets with the MRS and simulated observations of two representative systems, HR8799 and GJ504. In both systems, we could detect the presence of multiple molecules that were present in the input model of their atmospheres. We used two different approaches with single molecule forward models, used in literature, that are sensitive to detecting mainly H$_2$O, CO, CH$_4$, and NH$_3$, and a log-likelihood ratio test that uses full atmosphere forward models and is sensitive to a larger number of less dominant molecular species. We show that the MIRI MRS can be used to characterise widely separated giant exoplanets in the mid-IR using molecular mapping., Comment: 18 pages, 10 figures. Accepted for publication in Astronomy & Astrophysics

The Mid-Infrared Instrument (MIRI) on-board JWST will provide imaging, coronagraphy, low-resolution spectroscopy and medium-resolution spectroscopy at unprecedented sensitivity levels in the mid-infrared wavelength range. The Medium-Resolution Spectrometer (MRS) of MIRI is an integral field spectrograph that provides diffraction-limited spectroscopy between 4.9 and 28.3 um, within a FOV varying from 13 to 56" square. From ground testing, we calculate the physical parameters essential to general observers and calibrating the wavelength solution and resolving power of the MRS is critical for maximising the scientific performance of the instrument. We have used ground-based observations of discrete spectral features in combination with Fabry-Perot etalon spectra to characterize the wavelength solution and spectral resolving power of the MRS. We present the methodology used to derive the MRS spectral characterisation, which includes the precise wavelength coverage of each MRS sub-band, computation of the resolving power as a function of wavelength, and measuring slice-dependent spectral distortions. The resolving power varies from R3500 in channel 1 to R1500 in channel 4. Based on the ground test data, the wavelength calibration accuracy is estimated to be below one tenth of a pixel, with small systematic shifts due to the target position within a slice for unresolved sources, that have a maximum amplitude of about 0.25 spectral resolution elements. Based on ground test data, the MRS complies with the spectral requirements for both the R and wavelength accuracy for which it was designed. We also present the commissioning strategies and targets that will be followed to update the spectral characterisation of the MRS., Comment: 13 pages. Accepted for publication in A&A

Aims. We aim to detect molecules in the atmosphere of the young forming companion PDS70 b by searching for atmospheric absorption features typical of substellar objects. Methods. We obtained medium-resolution (R$\approx$5075) spectra of the PDS70 planetary system with the SINFONI integral field spectrograph at the Very Large Telescope. We applied molecular mapping, based on cross-correlation with synthetic spectra, to identify signatures of molecular species in the atmosphere of the planet. Results. Although the planet emission is clearly detected when resampling the data to lower resolution, no molecular species could be identified with the cross-correlation technique. We estimated upper limits on the abundances of H$_2$O, CO and CH$_4$ ($\log(X_\mathrm{mol}) < -4.0$, $-4.1$ and $-4.9$, respectively) assuming a clear atmosphere, and we explored the impact of clouds, which increase the upper limits by a factor up to 0.7 dex. Assuming that the observations directly probe the planet's atmosphere, we found a lack of molecular species compared to other directly imaged companions or field objects. Under the assumption that the planet atmosphere presents similar characteristics to other directly imaged planets, we conclude that a dusty environment surrounds the planet, effectively obscuring any feature generated in its atmosphere. We quantify the extinction necessary to impede the detection ($A_V\approx16-17$ mag), pointing to the possibility of higher optical thickness than previously estimated from other studies. Finally, the non-detection of molecular species conflicts with atmospheric models previously proposed to describe the forming planet. Conclusions. To unveil how giant planets form, a comprehensive approach that includes constraints from multiple techniques needs to be undertaken. Molecular mapping emerges as an alternative to more classical techniques like SED fitting., Comment: Accepted for publication in A&A (16 pages, 10 figures)

The Medium Resolution Spectrometer on board JWST/MIRI will give access to mid-IR spectra while retaining spatial information. With the unparalleled sensitivity of JWST and the MIRI detectors, the MRS has the potential to revolutionise our understanding of giant exoplanet atmospheres. Molecular mapping is a promising detection and characterisation technique used to study the spectra of directly imaged exoplanets. We aim to examine the feasibility and application of this technique to MRS observations. We used the instrument simulator MIRISIM to create mock observations of resolved star and exoplanet systems. As an input for the simulator, we used stellar and planet parameters from literature, with the planet spectrum being modelled with the radiative transfer code petitRADTRANS. After processing the raw data with the JWST pipeline, we high pass filter the data to account for the stellar point spread function, and used a forward modelling approach to detect the companions and constrain the chemical composition of their atmospheres through their molecular signatures. We identified limiting factors in spectroscopic characterisation of directly imaged exoplanets with the MRS and simulated observations of two representative systems, HR8799 and GJ504. In both systems, we could detect the presence of multiple molecules that were present in the input model of their atmospheres. We used two different approaches with single molecule forward models, used in literature, that are sensitive to detecting mainly H$_2$O, CO, CH$_4$, and NH$_3$, and a log-likelihood ratio test that uses full atmosphere forward models and is sensitive to a larger number of less dominant molecular species. We show that the MIRI MRS can be used to characterise widely separated giant exoplanets in the mid-IR using molecular mapping., Comment: 18 pages, 10 figures. Accepted for publication in Astronomy & Astrophysics

The Mid-Infrared Instrument (MIRI) on-board JWST will provide imaging, coronagraphy, low-resolution spectroscopy and medium-resolution spectroscopy at unprecedented sensitivity levels in the mid-infrared wavelength range. The Medium-Resolution Spectrometer (MRS) of MIRI is an integral field spectrograph that provides diffraction-limited spectroscopy between 4.9 and 28.3 um, within a FOV varying from 13 to 56" square. From ground testing, we calculate the physical parameters essential to general observers and calibrating the wavelength solution and resolving power of the MRS is critical for maximising the scientific performance of the instrument. We have used ground-based observations of discrete spectral features in combination with Fabry-Perot etalon spectra to characterize the wavelength solution and spectral resolving power of the MRS. We present the methodology used to derive the MRS spectral characterisation, which includes the precise wavelength coverage of each MRS sub-band, computation of the resolving power as a function of wavelength, and measuring slice-dependent spectral distortions. The resolving power varies from R3500 in channel 1 to R1500 in channel 4. Based on the ground test data, the wavelength calibration accuracy is estimated to be below one tenth of a pixel, with small systematic shifts due to the target position within a slice for unresolved sources, that have a maximum amplitude of about 0.25 spectral resolution elements. Based on ground test data, the MRS complies with the spectral requirements for both the R and wavelength accuracy for which it was designed. We also present the commissioning strategies and targets that will be followed to update the spectral characterisation of the MRS., Comment: 13 pages. Accepted for publication in A&A

Aims. We aim to detect molecules in the atmosphere of the young forming companion PDS70 b by searching for atmospheric absorption features typical of substellar objects. Methods. We obtained medium-resolution (R$\approx$5075) spectra of the PDS70 planetary system with the SINFONI integral field spectrograph at the Very Large Telescope. We applied molecular mapping, based on cross-correlation with synthetic spectra, to identify signatures of molecular species in the atmosphere of the planet. Results. Although the planet emission is clearly detected when resampling the data to lower resolution, no molecular species could be identified with the cross-correlation technique. We estimated upper limits on the abundances of H$_2$O, CO and CH$_4$ ($\log(X_\mathrm{mol}) < -4.0$, $-4.1$ and $-4.9$, respectively) assuming a clear atmosphere, and we explored the impact of clouds, which increase the upper limits by a factor up to 0.7 dex. Assuming that the observations directly probe the planet's atmosphere, we found a lack of molecular species compared to other directly imaged companions or field objects. Under the assumption that the planet atmosphere presents similar characteristics to other directly imaged planets, we conclude that a dusty environment surrounds the planet, effectively obscuring any feature generated in its atmosphere. We quantify the extinction necessary to impede the detection ($A_V\approx16-17$ mag), pointing to the possibility of higher optical thickness than previously estimated from other studies. Finally, the non-detection of molecular species conflicts with atmospheric models previously proposed to describe the forming planet. Conclusions. To unveil how giant planets form, a comprehensive approach that includes constraints from multiple techniques needs to be undertaken. Molecular mapping emerges as an alternative to more classical techniques like SED fitting., Comment: Accepted for publication in A&A (16 pages, 10 figures)

The aim of the study was to evaluate the outcomes of pedestal cup and METS coned hemipelvis implants for periacetabular reconstruction after type II pelvic resections, including complications, failure rates, and functional outcomes. We retrospectively reviewed 25 patients, divided in two groups, who underwent internal hemipelvectomy and periacetabular reconstruction using either a pedestal cup (Group A = 13) or a METS coned hemipelvis (Group B = 12). The clinical, radiological, and oncological outcomes, as well as the complications, were assessed. There were no differences between the two groups regarding capacity for independent walking at 12 months and functional results. Mechanical and nonmechanical complication rates were also similar for the two groups. The two-year cumulative incidence of failure was 7.6% (95% CI 0.3–18.3) for group A and 8.8 % (95% CI 1.7–20.1) for group B, while the four-year cumulative incidence of failure was 11% (95% CI 0.2–28.9) and 14.1% (95% CI 2.2–33.1), respectively. This study showed that both types of pelvic implants are reliable options for periacetabular reconstruction of bone defects after type II oncologic pelvic resections, having similar complication rates and functional results. © 2020 by Begell House, Inc.

BACKGROUND Patients with stage II-III colorectal cancer (CRC) treated with adjuvant chemotherapy, gain a 25% survival benefit. In the context of personalized medicine, there is a need to identify patients with CRC who may benefit from adjuvant chemotherapy. Molecular profiling could guide treatment decisions in these patients. Thymidylate synthase (TYMS) gene polymorphisms, KRAS and BRAF could be included in the molecular profile under consideration. AIM To investigate the association of TYMS gene polymorphisms, KRAS and BRAF mutations with survival of CRC patients treated with chemotherapy. METHODS A retrospective study studied formalin-fixed paraffin-embedded tissues (FFPEs) of consecutive patients treated with adjuvant chemotherapy during January/2005-January/2007. FFPEs were analysed with PCR for the detection of TYMS polymorphisms, mutated KRAS (mKRAS) and BRAF (mBRAF). Patients were classified into three groups (high, medium and low risk) according to 5'UTR TYMS polymorphisms Similarly, based on 3'UTR polymorphism ins/loss of heterozygosity (LOH) patients were allocated into two groups (high and low risk of relapse, respectively). Cox regression models examined the associated 5- year survival outcomes. RESULTS One hundred and thirty patients with early stage CRC (stage I-II: 55 patients; stage III 75 patients; colon: 70 patients; rectal: 60 patients) were treated with surgery and chemotherapy. The 5-year disease free survival and overall survival rate was 61.6% and 73.9% respectively. 5'UTR polymorphisms of intermediate TYMS polymorphisms (2RG/3RG, 2RG/LOH, 3RC/LOH) were associated with lower risk for relapse [hazard ratio (HR) 0.320, P = 0.02 and HR 0.343, P = 0.013 respectively] and death (HR 0.368, P = 0.031 and HR 0.394, P = 0.029 respectively). The 3'UTR polymorphism ins/LOH was independently associated with increased risk for disease recurrence (P = 0.001) and death (P = 0.005). mBRAF (3.8% of patients) was associated with increased r

Background Despite therapeutic advancements, gastric cancer (GC) remains a leading cause of death worldwide. Methods This retrospective cohort study statistically analyzed the clinicopathologic characteristics, treatments and outcomes of patients with potentially resectable GC managed at our institution between 2006 and 2010. The STROBE checklist was applied. Results Preoperative assessment of 164 GC patients (male: female ratio 1.87, median age 65 years) assigned 132 (80.5%) to total (56; 42.4%) or subtotal (76; 57.6%) gastrectomy. Resection margins were microscopically tumor-free (R0) in 100 (75.8%), microscopically infiltrated (R1) in 25 (18.9%) and macroscopically infiltrated (R2) in 7 (5.3%) patients. Nodal plane dissection was D0 in 34 (25.8%), D1 in 62 (47.0%) and D2 in 36 (27.3%) patients. Early GC was diagnosed in 19 patients (14.4%). Fluorouracil-based chemotherapy was administered in 69.7% and chemoradiation in 18.2% of patients. The 5-and 10-year survival rates of patients with R0 resection were 74% and 65.4%, respectively. The 2-year survival rates for R1 and R2 resection were 28.9% and 0% respectively. The 5-and 10-year survival rates according to nodal plane dissection were 55.6% and 41.4% for D2, and 53.2% and 49.7% for D1, respectively. On multivariate analysis, T4, N3 and R1/R2 remained independent negative prognostic factors for overall survival. Microscopic or macroscopic infiltration of surgical margins was the worst adverse prognostic factor for survival. Conclusion These results are equivalent to those from centers of excellence and indicate the urgent need for improvements in the field, particularly in the development of predictive models to guide personalized therapy. © 2019 Hellenic Society of Gastroenterology.

Histone H2AX undergoes phosphorylation as an answer to DNA double-strand breaks, which in turn are part of the oncogenic procedure. The detection of gamma-H2AX can potentially serve as a biomarker for transformation of normal tissue to premalignant and consequently to malignant tissues. The aim of this study was to evaluate the clinical significance of gamma-H2AX expression in breast cancer. Gamma-H2AX expression in tissues from 110 breast cancer patients was analyzed by immunohistochemistry and correlated with clinicopathological variables. Greater tumor size, higher grade, and the number of affected lymph nodes are significantly associated with greater values of gamma-H2AX. In addition, gamma-H2AX differs significantly among patients’ International Federation of Gynecology and Obstetrics stage. Higher values of estrogen receptor and progesterone receptor are significantly associated with lower gamma-H2AX values. In conclusion, a positive association between gamma-H2AX expression and infaust histopathological parameters was observed. © The Author(s) 2019.

Due to their evolution in the retroperitoneal space, pheochromocytomas may grow significantly in size and remain asymptomatic for a long period of time. Normal values of urine catecholamine levels must not preclude the diagnosis of these endocrine lesions. © 2018 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.

Background: Necrotizing fasciitis (NF) is a group of relatively rare infections, usually caused by two or more pathogens. It affects the skin and subcutaneous tissues of lower and upper limbs, perineal area (Fournier’s gangrene), and the abdominal wall. Early diagnosis and aggressive surgical management are of high significance for the management of this potentially lethal disease. Methods: We conducted a retrospective study in patients who presented, during the last decade, at four University Surgical Departments in the area of Athens, Greece, with an admission diagnosis of NF. Demographic, clinical, and laboratory data were gathered, and the preoperative and surgical treatment, as well as the postoperative treatment was analyzed for these patients. Results: A total of 62 patients were included in the study. The mean age of patients was 63.7 (47 male patients). Advanced age (over 65 years) (P < 0.01) and female sex (P = 0.04) correlated significantly with mortality. Perineum was the mostly infected site (46.8%), followed by the lower limbs (35.5%), the upper limbs, and the axillary region (8.1%). Diabetes mellitus was the most common coexisting disease (40.3%), followed by hypertension (25.8%) and obesity (17.7%). The most common symptom was local pain and tenderness (90.3%). Septic shock occurred in eight patients (12.9%) and strongly correlated with mortality (P < 0.01). Laboratory data were used to calculate the LRINEC score of every patient retrospectively; 26 patients (41.9%) had LRINEC score under 6, 20 patients (32.3%) had LRINEC score 6–8, and 16 patients (25.8%) had LRINEC score >9. Surgical debridement was performed in all patients (mean number of repeated debridement 4.8), and in 16 cases (25.8%) the infected limb was amputated. The mean length of hospital stay was 19.7 days, and the overall mortality rate of our series was 17.7%. Conclusion: Diagnosis of NF requires high suspect among clinicians, as its clinical image is non-specific. Laborator

AIM To investigate the impact of thymidylate synthase (TYMS ), KRAS and BRAF in the survival of metastatic colorectal cancer (mCRC) patients treated with chemotherapy. METHODS Clinical data were collected retrospectively from records of consecutive patients with mCRC treated with fluoropyrimidine-based chemotherapy from 1/2005 to 1/2007. Formalin-fixed paraffin-embedded tissues were retrieved for analysis. TYMS genotypes were identified with restriction fragment analysis PCR, while KRAS and BRAF mutation status was evaluated using real-Time PCR assays. TYMS gene polymorphisms of each of the 3' untranslated region (UTR) and 5'UTR were classified into three groups according to the probability they have for high, medium and low TYMS expression (and similar levels of risk) based on evidence from previous studies. Univariate and multivariate survival analyses were performed. RESULTS The analysis recovered 89 patients with mCRC (46.1% de novo metastatic disease and 53.9% relapsed). Of these, 46 patients (51.7%) had colon cancer and 43 (48.3%) rectal cancer as primary. All patients were treated with fluoropyrimidine-based chemotherapy (5FU or capecitabine) as single-Agent or in combination with irinotecan or/and oxaliplatin or/and bevacizumab. With a median follow-up time of 14.8 mo (range 0-119.8), 85 patients (95.5%) experienced disease progression, and 63 deaths (70.8%) were recorded. The 3-year and 5-year OS rate was 25.4% and 7.7% while the 3-year progression-free survival rate was 7.1%. Multivariate analysis of TYMS polymorphisms, KRAS and BRAF with clinicopathological parameters indicated that TYMS 3'UTR polymorphisms are associated with risk for disease progression and death (P < 0.05 and P < 0.03 respectively). When compared to tumors without any del allele (genotypes ins/ins and ins/loss of heterozygosity (LOH) linked with high TYMS expression) tumors with del/del genotype (low expression group) and tumors with ins/del or del/LOH (intermediat

Double-strand breaks are among the first procedures taking place in cancer formation and progression as a result of endogenic and exogenic factors. The histone variant H2AX undergoes phosphorylation at serine 139 due to double-strand breaks, and the gamma-H2AX is formatted as a result of genomic instability. The detection of gamma-H2AX can potentially serve as a biomarker for transformation of normal tissue to premalignant and consequently to malignant tissues. gamma-H2AX has already been investigated in a variety of cancer types, including breast, lung, colon, cervix, and ovary cancers. The prognostic value of gamma-H2AX is indicated in certain cancer types, such as breast or endometrial cancer, but further investigation is needed to establish gamma-H2AX as a prognostic marker. This review outlines the role of gamma-H2AX in cell cycle, and its formation as a result of DNA damage. We investigate the role of gamma-H2AX formation in several cancer types and its correlation with other prognostic factors, and we try to find out whether it fulfills the requirements for its establishment as a classical cancer prognostic factor. © 2017, © The Author(s) 2017.

73-year old woman was operated on with diffuse peritonitis and multiple abscesses throughout the mesentery which were drained. After the operation the patient could not recover. After an indicative computerized tomography the patient was re-explored. Perforation of the ileum and gastric perforation at the pylorus were found. There was no history of underline disease. The double perforation of the GI tract was surgically managed but the patient's course was fatal. © Copyright Celsius.

Background: The host's immune system is crucially involved in cancer development and progression. The ratio of regulatory to effector T-cells, as well as the interplay of T-cells with therapeutic agents, impact on cancer prognosis. The current study aimed to comparatively investigate the effect of metronomic and standard chemotherapy on the number and functionality of peripheral regulatory and effector T-cells in cancer patients. Methods: CD4+CD25+ regulatory and CD4+CD25- effector T-cells were purified from the peripheral blood of 36 cancer patients and co-cultured in the presence of a polyclonal stimulus. The proliferative capacity and frequency of CD4+CD25+/CD4+CD25- T-cells were analysed before and during various chemotherapeutic regimes, by ELISA and flow cytometry, respectively. Results: Chemotherapy shifted immune responses in favour of regulatory T-cells. The relative ratio of regulatory to effector T-cells increased, and the T-cell-mediated suppressive activity of regulatory on effector T-cells was augmented. This effect was more profound in metronomic than in standard chemotherapeutic approaches. Moreover, an association between the chemotherapy strategy followed and the mode of action of specific drugs (anti-mitotic, anti-DNA) was revealed. Conclusions: In comparison to standard chemotherapeutic strategies, metronomic approaches, though more patient-friendly, result in a significantly more prominent expansion of regulatory T-cells that aggravate the regulatory to effector T-cell imbalance. Our findings impact on the modulation of chemotherapy-treated patients' anti-tumor immunity and, thus, may be proven useful for selecting the most advantageous drug-delivery strategy, particularly when immunotherapeutics are eventually to be applied. © 2014 Koumarianou et al.; licensee BioMed Central Ltd.

Pancreatic neuroendocrine tumors (PNETs) share a unique genetic identity, functional behavior, and clinical course. Compared with tumors of the exocrine pancreas, they are rare and show a different biologic behavior and prognosis. On the basis of data from recent studies, all PNETs, outside of small insulinomas, should be considered potentially malignant and treated accordingly. Untreated tumors have a high possibility to grow locally into adjacent structures or spread to distant organs. Although surgical excision irrespective of tumor functioning or nonfunctioning state remains the cornerstone of therapy, providing the best disease-free and survival rates to date, the understanding of the genetic nature of the disease yields new 'targets' to consider in drug development. The aim of this review is to summarize all recent advances of genetic research and new drug development in terms of PNETs, especially their genetic identity and subsequent alterations leading to the development of near or total malignant activity, and the new medical treatment strategies of this potentially curable disease on the basis of therapeutical agents acting, where possible, at the genetic level. © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Background: Thoracoabdominal aortic aneurysm open surgery is accompanied by a significant incidence of renal failure due to renal ischemia. The effect of remote ischemic preconditioning (RIPC) in renal ischemia/reperfusion (IR) injury during a thoracoabdominal aortic aneurysm open repair approach was examined on an animal model. Materials and methods: Three groups of rats underwent the following operations respectively: (a) Sham operation in control group; (b) Renal IR injury produced by subphrenic aortic cross-clamping (45/45 min IR), in IR group; (c) The same renal IR injury following RIPC produced by a brief occlusion of the infrarenal aorta (15/15 min IR) in RIPC group. Levels of lactate, base excess, and malondialdehyde (MDA) were measured in selective blood samples from the left renal vein, while levels of MDA were measured in samples of kidney tissues. Results: Renal blood base excess was significantly reduced in IR and RIPC groups as compared to sham group, but it was significantly higher in RIPC compared to the IR group (-7.69 ± 0.62 versus -15.15 ± 0.86, P < 0.001). Renal blood lactate was significantly increased in both IR and RIPC groups as compared to the sham group, but it was significantly lower in RIPC group compared to IR group (6.76 ± 0.19 versus 11.99 ± 0.33, P < 0.001). Renal blood MDA was increased in both IR and RIPC groups compared to the sham group, but it was significantly less compared in the RIPC group compared to IR group (1.55 ± 0.38 versus 2.94 ± 0.16, P = 0.002). Finally, kidney tissue MDA was increased in both IR and RIPC groups versus sham group, but it was significantly lower in RIPC group compared to the IR group (5.92 ± 0.82 versus 13.98 ± 2.41, P = 0.005). Conclusions: RIPC induced by a temporary infrarenal aortic occlusion decreased the IR renal injury caused by subphrenic aortic cross-clamping. © 2009 Elsevier Inc. All rights reserved.

Foreign body ingestion is not uncommon, but in most patients the object passes without sequelae. In very few patients, the ingested foreign objects may perforate the gastrointestinal tract, causing potentially life-threatening complications. Pointed ingested objects such as toothpicks are the most common. Vascular perforation due to toothpick ingestion has rarely been reported. We present a patient with lower gastrointestinal bleeding secondary to simultaneous perforation of the sigmoid colon and the right iliac limb of an aortobiiliac endograft by an ingested toothpick. This arterioenteric fistula was treated in two stages. First as a bridging operation, a stent graft was inserted into the ipsilateral limb of the previous aortoiliac endograft to control the bleeding. Second, the aortoiliac endograft was removed, the aorta was oversewn, and an extra-anatomic axillobifemoral bypass restored the flow to the lower limbs. The colon perforation was treated with a proximal temporary loop colostomy. To our knowledge, this the first case of aortoiliac endograft-enteric fistula after endovascular abdominal aortic aneurysm repair caused by this extraordinary mechanism. © 2009 Society for Vascular Surgery.

We describe the imaging findings in a rare case of multifocal nodular form of hepatic epithelioid hemangioendothelioma on ultrasound (US) and dynamic contrast-enhanced spiral computed tomography (CT) and MRI. The nodules showed multilayered target appearance on MR images with prominent peripheral rim with high signal intensity (SI) on T1-weighted and very low SI on T2-weighted images, corresponding to thrombosed vascular channels. The above combination of imaging findings is to our knowledge distinct and should suggest the diagnosis of hepatic epithelioid hemangioendothelioma. © 2008 Wiley-Liss, Inc.

Background and aims: Incisional hernia repair with mesh is considered a clean operation and it is not recommended to be perfomed at the same time with a potentially contaminated operation. The aim of this study is to assess the short-term results of a group of patients who underwent a colon operation and simultaneous incisional hernia repair with an onlay polypropylene mesh technique. Patients and Methods: From November to June 2006, 19 patients underwent incisional hernia repair with polypropylene mesh, with simultaneous colonic operation. In 13 patients reestablishment of bowel continuity after a Hartmann procedure was done, whereas in four patients a loop colostomy was closed. Two patients underwent colectomy for cancer. Results: Post-operatively one patient had a seroma and two others had wound infections which required mesh removal. The mean follow-up was 70.15 +/- 48.40 months (range 3 to 142 months). During this period five patients died, four from progression of malignancy and one from myocardial infarction. Three patients (15.78 %) developed recurrence, two patients with previous Hartmann’s operation for complicated diverticulitis and wound infection and the third patient due to inappropriate mesh fixation with buttonhole hernia development. Conclusion: Prosthetic repair of incisional hernias can be safely performed simultaneously with a colonic operation, with art acceptable rate of infectious complications and recurrence. It is unjustifiable to avoid the use of mesh in a potentially contaminated field when an appropriate technique is used.

We report a very rare case of a 36-year-old woman with von Recklinghausen’s disease, synchronous carcinoid of the ampulla of Vater and stromal tumour of the jejunum, who presented with gastrointestinal bleeding and jaundice. (C) 2000 Harcourt Publishers Ltd.

This retrospective study was performed in order to correlate the season with the risk of rupture of an abdominal aortic aneurysm (AAA). From December 1968 to December 1990, 224 patients, 203 males (90.63%) and 21 females (9.37%), mean age 71 years, underwent surgery either urgently because of rupture or expansion (group A, 66 patients, 22.46%) or electively (group B, 158 patients, 70.53%) for AAA. Of the 66 patients in group A, 61 were male (92.4%) and five female (7.55%) with a mean age of 73 years. Of the 158 patients in group B, 142 were male (89.8%) and 16 female (10.1%). The frequency distribution of electively admitted and operated cases of AAA was shown to be similar during all seasons but the admissions of ruptured AAA were shown by non-parametric statistical analysis to increase during the autumn (p < 0.05) with 43.9% of the cases being admitted during September, October and November. The male to female ratio and the ratio of the number of aneurysms ruptured to the total number of aneurysms did not change significantly. The explanation of this phenomenon is obscure and needs further epidemiological investigation to assess the seasonal variability or various parameters such as hypertension.