600 research outputs found
Guided Descent to Mars. Vision-based Localization System for a Mars Probe
This paper aims to design a cheep vision-based system for automatic landing on Mar
Vision-based Localization System for a Mars Probe
This article deals with performances of a single camera vision-based system on a probe for automatique landing
A robust statistical estimation of the basic parameters of single stellar populations. I. Method
The colour-magnitude diagrams of resolved single stellar populations, such as
open and globular clusters, have provided the best natural laboratories to test
stellar evolution theory. Whilst a variety of techniques have been used to
infer the basic properties of these simple populations, systematic
uncertainties arise from the purely geometrical degeneracy produced by the
similar shape of isochrones of different ages and metallicities. Here we
present an objective and robust statistical technique which lifts this
degeneracy to a great extent through the use of a key observable: the number of
stars along the isochrone. Through extensive Monte Carlo simulations we show
that, for instance, we can infer the four main parameters (age, metallicity,
distance and reddening) in an objective way, along with robust confidence
intervals and their full covariance matrix. We show that systematic
uncertainties due to field contamination, unresolved binaries, initial or
present-day stellar mass function are either negligible or well under control.
This technique provides, for the first time, a proper way to infer with
unprecedented accuracy the fundamental properties of simple stellar
populations, in an easy-to-implement algorithm.Comment: 17 pages, 12 figures, MNRAS, in pres
Limitations of a commercial assay as diagnostic test of autoimmune encephalitis
Detection of neuronal surface antibodies (NSAb) is important for the diagnosis of autoimmune encephalitis (AE). Although most clinical laboratories use a commercial diagnostic kit (Euroimmun, Lübeck, Germany) based on indirect immunofluorescence on transfected cells (IIFA), clinical experience suggests diagnostic limitations. Here, we assessed the performance of the commercial IIFA in serum and CSF samples of patients with suspected AE previously examined by rat brain immunohistochemistry (Cohort A). Of 6213 samples, 404 (6.5%) showed brain immunostaining suggestive of NSAb: 163 (40%) were positive by commercial IIFA and 241 (60%) were negative. When these 241 samples were re-assessed with in-house IIFA, 42 (18%) were positive: 21 (9%) had NSAb against antigens not included in the commercial IIFA and the other 21 (9%) had NSAb against antigens included in the commercial kit (false negative results). False negative results occurred more frequently with CSF (29% vs 10% in serum) and predominantly affected GABABR (39%), LGI1 (17%) and AMPAR (11%) antibodies. Results were reproduced in a separate cohort (B) of 54 AE patients with LGI1, GABABR or AMPAR antibodies in CSF which were missed in 30% by commercial IIFA. Patients with discordant GABABR antibody results (positive in-house but negative commercial IIFA) were less likely to develop full-blown clinical syndrome; no significant clinical differences were noted for the other antibodies. Overall, NSAb testing by commercial IIFA led to false negative results in a substantial number of patients, mainly those affected by anti-LG1, GABABR or AMPAR encephalitis. If these disorders are suspected and commercial IIFA is negative, more comprehensive antibody studies are recommende
Pregnancy outcomes in anti-NMDA receptor encephalitis: Case series
To report the effects of anti-NMDA receptor (NMDAR) encephalitis in pregnant patients and their babies.We studied a retrospective cohort of patients who developed anti-NMDAR encephalitis during pregnancy or became pregnant while recovering from the encephalitis. In addition, we reviewed the English literature between 2010 and 2019 related to this topic.We studied 11 patients; 6 developed anti-NMDAR encephalitis during pregnancy, and 5 became pregnant while recovering. There were no obstetrical complications, but 6 (55%) babies were premature. Ten newborns were healthy, and 1 (9%) developed transient respiratory distress. Nine infants had assessable follow-up (median 18 months; range, 7-96 months), and all showed normal development. We identified 21 cases in the English literature. Obstetrical complications occurred in 7 (33%) pregnancies. Two patients died of septic shock (1 baby successfully delivered), another 2 had miscarriages, and in 2, the pregnancy was terminated. Sixteen babies (76%) were delivered, 9 (56%) premature. At birth, 13/16 (81%) newborns were healthy, 2/16 (13%) had transient neurologic or respiratory symptoms, and 1 (6%) died of brain edema. Follow-up (median 12 months; range, 6-36 months) was reported for 8 children: 7 (88%) showed normal development and behavior, and 1 (13%) cortical dysplasia. Immunotherapy was used during pregnancy in 7 (64%) of our patients and 18 (86%) of the reported cases, including rituximab in 4 cases, without adverse effects.Patients who develop anti-NMDAR encephalitis during pregnancy or become pregnant during recovery often have obstetrical complications, but most of the newborns are healthy and appear to have normal development.Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology
Exploratory study of an oral screening dysplasia program for HIV-infected men who have sex with men
Dysplasia; Screening; HIV-infectedDisplasia; Cribado; Infectado por el VIHDisplàsia; Cribratge; Infectat pel VIHBackground:
HIV-infected men who have sex with men (MSM) are at high risk to develop human papilloma virus (HPV)-related oropharyngeal cancer. The aim of our study was to assess the usefulness of a pilot oral dysplasia screening program and its correlation with an anal dysplasia screening program.
Methods:
This was a prospective study with HIV-infected MSM. Oral and anal screenings were performed based on HPV determination, liquid cytology, direct and microscopy oral examinations, high-resolution anoscopy and biopsies, if necessary.
Results:
A total of 103 patients were included. The mean age of the patients was 44.6 years, 55.3% were smokers, and 57.3% had a history of previous anal high-grade squamous intraepithelial lesions (HSILs). The prevalence of oral HPV infections was 14% (9% HPV-high risk), the prevalence of abnormal cytology was 25.2%, and in 4.8% of the patients, oral examinations showed suspicious HSILs. Oral microscopy did not detect additional lesions that visual inspection. Five oral biopsies were performed and the results were normal. No risk factors for oral HPV infections were identified. The prevalence of anal HPV infections was 88.3% (76.7% HPV-high risk), 52.9% of the patients had altered cytology, and in 45.6% anoscopy showed changes suggestive of HSILs. Seventy-two anal biopsies were performed, detecting 25 cases of HSILs (24.3%).
A poor correlation was observed between oral and anal HPV infections (κ = 0.037).
Conclusions:
The prevalence of oral HPV infections, abnormal cytology and lesions in HIV-infected MSM was low, and their correlation with anal HPV-related lesions was slight. These results confirm the current barriers to oral dysplasia screening techniques.Study funded by program MISP of MSD (Merck HPV Investigator Study Program). MISP project code 58237
Multicenter phase II study of matured dendritic cells pulsed with melanoma cell line lysates in patients with advanced melanoma
<p>Abstract</p> <p>Background</p> <p>Several single center studies have provided evidence of immune activation and antitumor activity of therapeutic vaccination with dendritic cells (DC) in patients with metastatic melanoma. The efficacy of this approach in patients with favorable prognosis metastatic melanoma limited to the skin, subcutaneous tissues and lung (stages IIIc, M1a, M1b) was tested in a multicenter two stage phase 2 study with centralized DC manufacturing.</p> <p>Methods</p> <p>The vaccine (IDD-3) consisted 8 doses of autologous monocyte-derived matured DC generated in serum-free medium with granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin-13 (IL-13), pulsed with lysates of three allogeneic melanoma cell lines, and matured with interferon gamma. The primary endpoint was antitumor activity.</p> <p>Results</p> <p>Among 33 patients who received IDD-3 there was one complete response (CR), two partial responses (PR), and six patients had stable disease (SD) lasting more than eight weeks. The overall prospectively defined tumor growth control rate was 27% (90% confidence interval of 13-46%). IDD-3 administration had minimal toxicity and it resulted in a high frequency of immune activation to immunizing melanoma antigens as assessed by <it>in vitro </it>immune monitoring assays.</p> <p>Conclusions</p> <p>The administration of matured DC loaded with tumor lysates has significant immunogenicity and antitumor activity in patients with limited metastatic melanoma.</p> <p>Clinical trial registration</p> <p>NCT00107159.</p
A Pilot Study for Metabolic Profiling of Obesity-Associated Microbial Gut Dysbiosis in Male Wistar Rats
Obesity is one of the most incident and concerning disease worldwide. Definite strategies to prevent obesity and related complications remain elusive. Among the risk factors of the onset of obesity, gut microbiota might play an important role in the pathogenesis of the disease, and it has received extensive attention because it affects the host metabolism. In this study, we aimed to define a metabolic profile of the segregated obesity-associated gut dysbiosis risk factor. The study of the metabolome, in an obesity-associated gut dysbiosis model, provides a relevant way for the discrimination on the different biomarkers in the obesity onset. Thus, we developed a model of this obesity risk factors through the transference of gut microbiota from obese to non-obese male Wistar rats and performed a subsequent metabolic analysis in the receptor rats. Our results showed alterations in the lipid metabolism in plasma and in the phenylalanine metabolism in urine. In consequence, we have identified metabolic changes characterized by: (1) an increase in DG:34:2 in plasma, a decrease in hippurate, (2) an increase in 3-HPPA, and (3) an increase in o-coumaric acid. Hereby, we propose these metabolites as a metabolic profile associated to a segregated dysbiosis state related to obesity disease
Post-mortem neuropathologic examination of a 5-case series of CAR T-cell treated patients
Introduction: Chimeric antigen receptor (CAR) T-cell therapy is a promising immunotherapy for the treatment of refractory hematopoietic malignancies. Adverse events are common, and neurotoxicity is one of the most important. However, the physiopathology is unknown and neuropathologic information is scarce.Materials and methods: Post-mortem examination of 6 brains from patients that underwent CAR T-cell therapy from 2017 to 2022. In all cases, polymerase chain reaction (PCR) in paraffin blocks for the detection of CAR T cells was performed.Results: Two patients died of hematologic progression, while the others died of cytokine release syndrome, lung infection, encephalomyelitis, and acute liver failure. Two out of 6 presented neurological symptoms, one with extracranial malignancy progression and the other with encephalomyelitis. The neuropathology of the latter showed severe perivascular and interstitial lymphocytic infiltration, predominantly CD8+, together with a diffuse interstitial histiocytic infiltration, affecting mainly the spinal cord, midbrain, and hippocampus, and a diffuse gliosis of basal ganglia, hippocampus, and brainstem. Microbiological studies were negative for neurotropic viruses, and PCR failed to detect CAR T -cells. Another case without detectable neurological signs showed cortical and subcortical gliosis due to acute hypoxic-ischemic damage. The remaining 4 cases only showed a mild patchy gliosis and microglial activation, and CAR T cells were detected by PCR only in one of them.Conclusions: In this series of patients that died after CAR T-cell therapy, we predominantly found non-specific or minimal neuropathological changes. CAR T-cell related toxicity may not be the only cause of neurological symptoms, and the autopsy could detect additional pathological findings
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