The intriguing observations of the Swift/Burst Alert Telescope (BAT) X-ray flash (XRF) 060218 and the BATSE-BeppoSAX gamma-ray burst GRB 980425, both with much lower luminosity and redshift compared ...to other observed bursts, naturally lead to the question of how these low-luminosity (LL) bursts are related to high-luminosity (HL) bursts. Incorporating the constraints from both the flux-limited samples observed with Compton Gamma-ray Observatory (CGRO)/BATSE and Swift/BAT and the redshift-known gamma-ray burst (GRB) sample, we investigate the luminosity function for both LL and HL GRBs through simulations. Our multiple criteria, including the log N− log P distributions from the flux-limited GRB sample, the redshift and luminosity distributions of the redshift-known sample and the detection ratio of HL and LL GRBs with Swift/BAT, provide a set of stringent constraints to the luminosity function. Assuming that the GRB rate follows the star formation rate (SFR), our simulations show that a simple power law (PL) or a broken power-law model of luminosity function fails to reproduce the observations and a new component is required. This component can be modelled with a broken power, which is characterized by a sharp increase in the burst number at around L < 1047 erg s−1. The lack of detection of moderate-luminosity GRBs at redshift ∼0.3 indicates that this feature is not due to the observational biases. The inferred local rate, ρ0, of LL GRBs from our model is ∼200 Gpc−3 yr−1 at ∼1047 erg s−1, much larger than that of HL GRBs. These results imply that LL GRBs could be a separate GRB population from HL GRBs. The recent discovery of a local X-ray transient 080109/SN 2008D would strengthen our conclusion if the observed non-thermal emission has a similar origin as the prompt emission of most GRBs and XRFs.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
To describe the functional and anatomical outcomes of pars plana vitrectomy with epiretinal membrane and internal limiting membrane peel in eyes with and without ectopic inner foveal layers (EIFLs).
...In this retrospective multicenter study, patients diagnosed with idiopathic epiretinal membranes who underwent pars plana vitrectomy with epiretinal membrane and internal limiting membrane peel were enrolled, with a minimum follow-up of 12 months. Preoperative and postoperative spectral domain optical coherence tomography scans were qualitatively and quantitatively evaluated. The association of the EIFL and other spectral domain optical coherence tomography parameters with preoperative and postoperative best-corrected visual acuity (BCVA) was analyzed.
One hundred eleven eyes of 107 patients were included. Preoperatively, the EIFLs were present in 56 of 111 eyes (50.4%). The presence of EIFL was significantly associated with lower preoperative and postoperative BCVA (P < 0.001). Ectopic inner foveal layer thickness was negatively correlated with preoperative BCVA (r = 0.58, P < 0.001). Postoperatively, the EIFL persisted in 51 of 56 eyes (91%) with Stage 3 and 4 epiretinal membranes. Ectopic inner foveal layer thickness decreased significantly after surgery (P < 0.001), but postoperative EIFL thinning had no direct effect on postoperative change in BCVA. At 12 months from surgery, EIFL thickness maintained a significant negative correlation with BCVA (r = 0.55, P < 0.001).
The presence of EIFL should be considered a negative prognostic factor for postoperative anatomical and functional recovery.
The origin and progenitors of short-hard gamma-ray bursts (GRBs) remain a puzzle and a highly debated topic. Recent Swift observations suggest that these GRBs may be related to catastrophic ...explosions in degenerate compact stars, denoted as 'Type I' GRBs. The most popular models include the merger of two compact stellar objects (NS-NS or NS-BH). We utilize a Monte Carlo approach to determine whether a merger progenitor model can self-consistently account for all the observations of short-hard GRBs, including a sample with redshift measurements in the Swift era (z-known sample) and the CGRO/BATSE sample. We apply various merger time delay distributions invoked in compact star merger models to derive the redshift distributions of these Type I GRBs, and then constrain the unknown luminosity function of Type I GRBs using the observed luminosity-redshift (L-z) distributions of the z-known sample. The best luminosity function model, together with the adopted merger delay model, is then applied to confront the peak flux distribution (log N-log P distribution) of the BATSE and Swift samples. We find that for all the merger models invoking a range of merger delay timescales (including those invoking a large fraction of 'prompt mergers'), it is difficult to reconcile the models with all the data. The data are instead statistically consistent with the following two possible scenarios. First, that short/hard GRBs are a superposition of compact-star-merger-origin (Type I) GRBs and a population of GRBs that track the star formation history, which are probably related to the deaths of massive stars (Type II GRBs). Second, the entire short/hard GRB population is consistent with a typical delay of 2 Gyr with respect to the star formation history with modest scatter. This may point toward a different Type I progenitor than the traditional compact star merger models.
Histopathological and molecular features have been proposed to hold prognostic information, but few have been validated. The aim of this retrospective study was to validate the Genetic And ...Morphological Evaluation ('GAME') score and assess the impact of histological characteristics on the prognosis in patients with colorectal liver metastases.
Data were collected from 176 patients with metastatic colorectal cancer undergoing liver resection at Hospital de la Santa Creu i Sant Pau. Patients were classified into Genetic And Morphological Evaluation score groups and relapse-free survival and overall survival were calculated. Histopathological changes in colorectal liver metastases were documented and prognostic variables were selected to create a post-surgery score, called the Histopathological, Clinical, And Molecular ('HICAM') score.
Regarding the Genetic And Morphological Evaluation score, the high-risk group had a median relapse-free survival of 8.8 months, compared with 20.5 months for the low-risk group (P = 0.005), and the high-risk group had a median overall survival of 37.8 months, compared with 67.0 months for the low-risk group (P = 0.005). Histological examination of 144 liver samples showed that the desertic immune phenotype was associated with worse overall survival in the multivariable analysis (P = 0.020). The Histopathological, Clinical, And Molecular score variables were age at diagnosis, tumour burden score, carcinoembryonic antigen levels greater than or equal to 20 ng/ml, primary tumour resection, TNM stage at diagnosis, molecular status, histopathological growth patterns, and immune phenotypes of the liver. The high-risk group had a median relapse-free survival of 8.4 months, compared with 20.4 months for the low-risk group (P < 0.001), and a median overall survival of 30.4 months, compared with 105.0 months for the low-risk group (P < 0.001).
The Genetic And Morphological Evaluation score was validated as a preoperative prognostic tool to predict candidacy for liver resection. The Histopathological, Clinical, And Molecular score could be useful to assess adjuvant treatment after hepatic resection.
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BFBNIB, FZAB, GIS, IJS, KILJ, NUK, OILJ, SBCE, SBMB, UL, UPUK
Prompted by various analyses of long (type II) gamma-ray burst (GRB) rates and their relationship to the cosmic star formation history, metallicity and luminosity function evolution, we ...systematically analyse these effects with a Monte Carlo code. We test various cosmic star formation history models including analytical and empirical models as well as those derived from cosmological simulations. We also explore expressions for metallicity enhancement of the GRB rate with redshift, as presented in the literature, and discuss improvements to these analytic expressions from the point of view of galactic evolution. These are also compared to cosmological simulations on metal enrichment. Additionally, we explore possible evolutionary effects of the GRB rate and luminosity function with redshift. The simulated results are tested with the observed Swift sample including the L, z and peak flux (log N-log P) distributions. The observational data imply that an increase in the GRB rate is necessary to account for the observations at high redshift, although the form of this enhancement is unclear. A rate increase due to lower metallicity at higher redshift may not be the singular cause and is subject to a variety of uncertainties. Alternatively, evolution of the GRB luminosity function break with redshift shows promise as a possible alternative.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
ABSTRACT
Using the gamma-ray bursts (GRBs) simultaneously detected by Swift/Burst Alert Telescope (BAT) and Fermi/Gamma-ray Burst Monitor (GBM), we performed a joint spectral and temporal analysis of ...the prompt emission data and confirmed the rough correlation between the BAT-band photon index Γ;BAT and the peak spectral energy E
peak. With the redshift-known subsample, we derived the isotropic gamma-ray energy E
γ, iso and also confirmed the E
γ,iso − E
peak,rest relation, with a larger scatter than the Amati sample but consistent with GBM team analyses. We also compare the T
90 values derived in the GBM band with those derived in the BAT band and find that for long GRBs the BAT T
90 is usually longer than the GBM T
90, while for short GRBs the trend reverses. This is consistent with the soft/hard nature of long/short GRBs and suggests the importance of an energy-dependent temporal analysis of GRBs.
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The two high-redshift gamma-ray bursts, GRB 080913 at z = 6.7 and GRB 090423 at z = 8.2, recently detected by Swift appear as intrinsically short, hard GRBs. They could have been recognized by BATSE ...as short/hard GRBs should they have occurred at z <= 1. In order to address their physical origin, we perform a more thorough investigation on two physically distinct types (Type I/II) of cosmological GRBs and their observational characteristics. We reiterate the definitions of Type I/II GRBs and then review the following observational criteria and their physical motivations: supernova (SN) association, specific star-forming rate (SFR) of the host galaxy, location offset, duration, hardness, spectral lag, statistical correlations, energetics and collimation, afterglow properties, redshift distribution, luminosity function, and gravitational wave signature. Contrary to the traditional approach of assigning the physical category based on the gamma-ray properties (duration, hardness, and spectral lag), we take an alternative approach to define the Type I and Type II Gold Samples using several criteria that are more directly related to the GRB progenitors (SN association, host galaxy type, and specific SFR). We then study the properties of the two Gold Samples and compare them with the traditional long/soft and short/hard samples. We find that the Type II Gold Sample reasonably tracks the long/soft population, although it includes several intrinsically short (shorter than 1 s in the rest frame) GRBs. The Type I Gold Sample only has five GRBs, four of which are not strictly short but have extended emission. Other short/hard GRBs detected in the Swift era represent the BATSE short/hard sample well, but it is unclear whether all of them belong to Type I. We suggest that some (probably even most) high-luminosity short/hard GRBs instead belong to Type II. Based on multiple observational criteria, we suggest that GRB 080913 and GRB 090423 are more likely Type II events. In general, we acknowledge that it is not always straightforward to discern the physical categories of GRBs, and re-emphasize the importance of invoking multiple observational criteria. We cautiously propose an operational procedure to infer the physical origin of a given GRB with available multiple observational criteria, with various caveats laid out.
Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) play a pivotal role in stimulating motivational behavior toward food and energy metabolism. Aberrant functioning of the endocannabinoid system has ...been observed in extreme weight conditions (EWCs), suggesting it may influence pathophysiology. Then, we aimed to analyze fasting AEA and 2-AG plasma concentrations among individuals with EWC (i.e., anorexia nervosa AN and obesity with and without eating disorders EDs) compared with healthy controls (HCs), and its association with clinical variables and body mass index (BMI).
The sample included 113 adult women. Fifty-seven belonged to the obesity group, 37 without EDs (OB-ED) and 20 with ED (OB+ED classified within the binge spectrum disorders), 27 individuals from the AN group, and 29 from the HC group. Peripheral blood samples, several clinical variables, and BMI were evaluated.
Unlike 2-AG, AEA concentrations showed significant differences between groups (
< 0.001). Increased AEA was observed in the OB-ED and OB+ED compared with both HC and AN group, respectively. Likewise, AEA was differentially associated with emotional dysregulation, general psychopathology, food addiction, and BMI in all clinical groups.
These results support the interaction between biological and clinical factors contributing to delineating vulnerability pathways in EWC that could help fit personalized therapeutic approaches.
Capecitabine-Related Thrombotic Microangiopathy Mateo, Francisco J. Pelegrín; Guasch, Anna Dominguez; Pineda, Jose Andrés Guerrero ...
Journal of gastrointestinal cancer,
06/2024, Volume:
55, Issue:
2
Journal Article
Peer reviewed
Purpose
Renal injury is common in cancer patients and its etiology is multifactorial. Different patterns of renal histological lesions have been described in relation to oncologic treatments, notably ...acute tubular necrosis and tubulointerstitial nephritis, but also thrombotic microangiopathy (TMA).
Methods
We report a case of TMA secondary to capecitabine in an 82-year-old woman diagnosed with localized colon adenocarcinoma.
Results
The patient, with previous normal kidney function, presented with renal impairment during the fourth cycle of chemotherapy. After potential nephrotoxic factors were ruled out, capecitabine was discontinued and a kidney biopsy was performed, which displayed TMA lesions. An improvement in renal function was observed after definitive cessation of cytotoxic chemotherapy. Although rare, renal toxicity in the form of TMA may be associated with the use of cytotoxic agents such as gemcitabine, but there is no reported evidence of its association to capecitabine. Early withdrawal of the drug and nephrology consultation is necessary to prevent irreversible damage.
Conclusion
We describe, to our knowledge, the first case reported in the literature regarding the possible association of TMA and capecitabine.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose
This study reviews evidence and provides recommendations for the ideal setting of intravitreal injection (IVI) administration of vascular endothelial growth factor (VEGF) inhibitors.
Methods
...A multi-step approach was employed, including content analysis of regulations and guidelines, a systematic literature review, and an international survey assessing perioperative complications and endophthalmitis incidence in relation to injection settings. The literature review searched PubMed and Cochrane databases from 2006 to 2022, focusing on studies reporting correlations between complications and treatment settings. The survey utilized a web-based questionnaire distributed to clinical sites and the international ophthalmic community, with data managed using electronic capture tools.
Results
We reviewed regulations and guidelines from 23 countries across five continents, finding significant variation in IVI administration settings. In most countries, IVI is primarily administered in outpatient clean rooms (96%) or offices (39%), while in others, it is restricted to ambulatory surgery rooms or hospital-based operating theatres (4%). The literature review found that endophthalmitis risk after IVI is generally low (0.01% to 0.26% per procedure), with no significant difference between office-based and operating room settings. The international survey (20 centers, 96,624 anti-VEGF injections) found low overall incidences of severe perioperative systemic adverse events and endophthalmitis, independent of injection settings.
Conclusion
No significant differences in perioperative complications were observed among various settings, including operating theatres, ambulatory surgery rooms, offices, hospitals, or extra-hospital environments. Choosing the appropriate clinical setting can optimize patient management, potentially increasing effectiveness, quality, productivity, and capacity.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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