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21.
We tested the use of nasal swabs spotted onto filter paper (Whatman 3M) for the molecular diagnosis of SARS-CoV-2 infection. Spots of a positive nasal swab in conservation medium (B.1.177 strain, 21Ct) were still positive (duo E-gene/IP4) after 10, 20, and 30 days of conservation at room temperature, with Ct values of 28, 27, and 26, respectively. Direct spotting of the swab at bedside (omicron strain) still gave a positive result after 10 days in two RT-qPCR systems: 33.7 Ct using duo E-gene/IP4, and 34.8 using a specific Omicron system. Spotting of a dilution range of media spiked with the Delta (strain 2021/FR/0610, lineage B 1.617.2) and Omicron strains (strain UVE/SARS-CoV-2/2021/FR/1514) showed a threshold of 0.04 TCID50 after 10 days of conservation. We show, for the first time, that this simple and low-cost conservation method can be used to store samples for RT-qPCR against SARS-CoV-2 for up to at least 1 month.  相似文献   
22.
Clémence Jacquin  Emilie Landais  Céline Poirsier  Alexandra Afenjar  Ahmad Akhavi  Nathalie Bednarek  Caroline Bénech  Adeline Bonnard  Damien Bosquet  Lydie Burglen  Patrick Callier  Sandra Chantot-Bastaraud  Christine Coubes  Charles Coutton  Bruno Delobel  Margaux Descharmes  Jean-Michel Dupont  Vincent Gatinois  Nicolas Gruchy  Sarah Guterman  Abdelkader Heddar  Lucas Herissant  Delphine Heron  Bertrand Isidor  Pauline Jaeger  Guillaume Jouret  Boris Keren  Paul Kuentz  Cedric Le Caignec  Jonathan Levy  Nathalie Lopez  Zoe Manssens  Dominique Martin-Coignard  Isabelle Marey  Cyril Mignot  Chantal Missirian  Céline Pebrel-Richard  Lucile Pinson  Jacques Puechberty  Sylvia Redon  Damien Sanlaville  Marta Spodenkiewicz  Anne-Claude Tabet  Alain Verloes  Gaelle Vieville  Catherine Yardin  François Vialard  Martine Doco-Fenzy 《American journal of medical genetics. Part A》2023,191(2):445-458
Chromosome 1p36 deletion syndrome (1p36DS) is one of the most common terminal deletion syndromes (incidence between 1/5000 and 1/10,000 live births in the American population), due to a heterozygous deletion of part of the short arm of chromosome 1. The 1p36DS is characterized by typical craniofacial features, developmental delay/intellectual disability, hypotonia, epilepsy, cardiomyopathy/congenital heart defect, brain abnormalities, hearing loss, eyes/vision problem, and short stature. The aim of our study was to (1) evaluate the incidence of the 1p36DS in the French population compared to 22q11.2 deletion syndrome and trisomy 21; (2) review the postnatal phenotype related to microarray data, compared to previously publish prenatal data. Thanks to a collaboration with the ACLF (Association des Cytogénéticiens de Langue Française), we have collected data of 86 patients constituting, to the best of our knowledge, the second-largest cohort of 1p36DS patients in the literature. We estimated an average of at least 10 cases per year in France. 1p36DS seems to be much less frequent than 22q11.2 deletion syndrome and trisomy 21. Patients presented mainly dysmorphism, microcephaly, developmental delay/intellectual disability, hypotonia, epilepsy, brain malformations, behavioral disorders, cardiomyopathy, or cardiovascular malformations and, pre and/or postnatal growth retardation. Cardiac abnormalities, brain malformations, and epilepsy were more frequent in distal deletions, whereas microcephaly was more common in proximal deletions. Mapping and genotype–phenotype correlation allowed us to identify four critical regions responsible for intellectual disability. This study highlights some phenotypic variability, according to the deletion position, and helps to refine the phenotype of 1p36DS, allowing improved management and follow-up of patients.  相似文献   
23.
Ethanol is an antagonist of the N-methyl-D-aspartate (NMDA) glutamate receptor. Ethanol dependence upregulates NMDA receptors and contributes to crosstolerance with selective NMDA receptor antagonists in animals. This study evaluated whether recovering ethanol-dependent patients show evidence of a reduced level of response to the effects of the NMDA receptor antagonist, ketamine. In this double-blind study, 34 recently detoxified alcohol-dependent patients and 26 healthy comparison subjects completed 3 test days involving a 40-min infusion of saline, ketamine 0.1 mg/kg, or ketamine 0.5 mg/kg in a randomized order. Recovering ethanol-dependent patients showed reduced perceptual alterations, dysphoric mood, and impairments in executive cognitive functions during ketamine infusion relative to the healthy comparison group. No attenuation of ketamine-induced amnestic effects, euphoria, or activation was observed. The alterations in NMDA receptor function observed in recovering ethanol-dependent patients may have important implications for ethanol tolerance, ethanol dependence, and the treatment of alcoholism.  相似文献   
24.
Twenty-five patients with osteolytic metastases had computed tomography (CT) scans before and 3 months after palliative radiotherapy. The median % density change following single 8 Gy, 20 Gy/5#, 30 Gy/10# were: 128 (range 98–255), 141 (79–342), and 145 (65–235), respectively. It is feasible to evaluate remineralization of osteolytic lesions with palliative radiotherapy.  相似文献   
25.
PURPOSE: Arsenic trioxide (ATO) is capable of inducing a high hematologic response rate in patients with relapsed acute promyelocytic leukemia (APL). Preclinical observations have indicated that all-trans-retinoic acid (ATRA) may strongly enhance the response to ATO. PATIENTS AND METHODS: Between 1998 and 2001, we conducted a randomized study of ATO alone versus ATO plus ATRA in 20 patients with relapsed APL, all previously treated with ATRA-containing chemotherapy. The primary objective was to demonstrate a significant reduction in the time necessary to obtain a complete remission (CR) in the ATO/ATRA group compared with the ATO group. Secondary objectives were safety and molecular response. RESULTS: The CR rate after one ATO with or without ATRA induction cycle was 80%. Clinical and pharmacokinetic observations indicated that the main mechanism of action of ATO in vivo was the induction of APL cell differentiation. Hematologic and molecular response, time necessary to reach CR, and outcome were comparable in both treatment groups. Of 16 CR patients, three patients who reached a molecular remission after one induction cycle had all received chemotherapy for a treatment-induced hyperleukocytosis. Three additional patients who received further additional ATO with or without ATRA cycles converted later to molecular negativity. CONCLUSION: ATRA did not seem to significantly improve the response to ATO in patients relapsing from APL. Other potential combinations, including ATO plus chemotherapy, have to be tested.  相似文献   
26.
27.
BACKGROUND AND PURPOSE: To examine the incidence of pain flare following external beam radiotherapy and to determine what constitutes a meaningful change in pain scores in the treatment of bone metastases. PATIENTS AND METHODS: Patients with bone metastases treated with external beam radiotherapy were asked to score their pain on a scale of 0-10 before the treatment (baseline), daily during the treatment and for 10 days after completion of external beam radiation. Pain flare was defined as a two-point increase from baseline pain in the pain scale of 0-10 with no decrease in analgesic intake or a 25% increase in analgesic intake employing daily oral morphine equivalent with no decrease in pain score. To distinguish pain flare from progression of pain, we required the pain score and analgesic intake to return back to baseline levels after the increase/flare. They were also asked to indicate if their pain changed during that time compared to pre-treatment level. The change in pain score was compared with patient perception. RESULTS: Eighty-eight patients were evaluated in this study. There were 49 male and 39 female patients with the median age of 70 years. Twelve of 88 patients (14%) had pain flare on day 1. The overall incidence of pain flare during the study period ranged from 2 to 16%. A total of 797 pain scorings were obtained. Patients perceived an improvement in pain when their self-reported pain score decreased by at least two points. CONCLUSIONS: Our study confirms the occurrence of pain flare following the external beam radiotherapy in the treatment of bone metastases. Further studies are required to predict who are at risk for flare. Appropriate measures can be taken to alleviate the pain flare. The finding in the meaningful change in pain scores supports the investigator-defined partial response used in some clinical trials.  相似文献   
28.
Lassa fever is a viral hemorrhagic fever treated with supportive care and the broad-spectrum antiviral drug ribavirin. The pathophysiology, especially the role of hyperinflammation, of this disease is unknown. We report successful remission of complicated Lassa fever in 2 patients in Nigeria who received the antiinflammatory agent dexamethasone and standard ribavirin.  相似文献   
29.
The porosity of differently wetted carbonaceous material with disordered mesoporosity was investigated using low-field 1H NMR relaxometry. Spin–spin relaxation (relaxation time T2) was measured using the CPMG pulse sequence. We present a non-linear optimization method for the conversion of relaxation curves to the distribution of relaxation times by using non-specialized software. Our procedure consists of searching for the number of components, relaxation times, and their amplitudes, related to different types of hydrogen nuclei in the sample wetted with different amounts of water (different water-to-carbon ratio). We found that a maximum of five components with different relaxation times was sufficient to describe the observed relaxation. The individual components were attributed to a tightly bounded surface water layer (T2 up to 2 ms), water in small pores especially supermicropores (2 < T2 < 7 ms), mesopores (7 < T2 < 20 ms), water in large cavities between particles (20–1500 ms), and bulk water surrounding the materials (T2 > 1500 ms). To recalculate the distribution of relaxation times to the pore size distribution, we calculated the surface relaxivity based on the results provided by additional characterization techniques, such as thermoporometry (TPM) and N2/−196 °C physisorption.  相似文献   
30.
This research paper is concerned with the experimental study of high-feed end milling of 1.4541 (X6CrNiTi18-10) stainless steel with replaceable cermet plates. Several machining operations were performed under different cutting conditions. The variable values were depth of cut, feed per tooth and cutting speed. The results were analyzed, and cutting forces were evaluated for dependence on cutting conditions (cutting speed, depth of cut, feed per tooth). The obtained data were statistically processed and plotted in graphs. It was found that the percentage distribution of cutting forces changed as the tool load increased. The ratio of forces acting in individual axes also changed with varying trends. An increasing trend was recorded in the x and y axes, while a decreasing trend was recorded in the z axis. Measured change, approximately 10%, can no longer be neglected as it can significantly influence the clamping stability of a part.  相似文献   
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