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81.
Cell-free DNA (Cf-DNA) fragments may constitute an easy-to-measure molecular tool for guiding the choice of care provided to infertile couples who benefit assisted reproductive technology (ART) programmes. Data on Cf-DNA levels in the seminal plasma of men with sperm alterations are scarce. The objective of the present study was to quantify the presence of Cf-DNA in semen by using a quantitative real-time PCR. We compared men with abnormal sperm characteristics (n = 21) with normospermic controls (n = 21). The PCR assay evidenced significantly higher mean Cf-DNA levels in patients with sperm abnormalities than in controls (2.09 versus 1.18 µg/ml, respectively; p = .0003). The Cf-DNA levels were notably higher in men with azoospermia (3.65 µg/ml, versus 1.34 µg/ml in matched controls; p = .03) and men with teratozoospermia (1.80 µg/ml, versus 1.29 µg/ml in matched controls; p = .008). Our data report a significant association between elevated Cf-DNA levels and sperm abnormalities. These results may open up new diagnostic and prognostic perspectives in male infertility.  相似文献   
82.
BackgroundOwing to improved quality of computed tomography, a new category of complicated acute diverticulitis, including patients with pericolic air but without abscess formation, can be defined (Hinchey 1a). Recent studies question whether this new category of acute diverticulitis could be treated as uncomplicated cases. The aim of our study is to report on the clinical course of acute diverticulitis Hinchey 1a in current clinical practice.MethodsFor this multicenter retrospective cohort study, patients presenting at the emergency department with Hinchey 1a acute diverticulitis as demonstrated by computed tomography scan, were identified. The primary outcome measure was successful conservative treatment with observation alone, antibiotics, and/or hospital admission. Readmissions, percutaneous drainage of abscesses, and emergency operations were considered as failure.ResultsBetween October 2016 and October 2018, 1,199 patients were clinically suspected for acute diverticulitis, of whom 101 (8.4%) were radiologically diagnosed to have type 1a acute diverticulitis (average age 57 (±13) years, 45% female) and started with conservative treatment. This was successful in 86 (85%) patients. One of the 15 unsuccessfully treated patients (1%) received percutaneous drainage of an abdominal abscess. Surgery was required in 9 cases (9%) after a median time of 6 days (range, 3 to 69 days). Although a difference in the volume of extraluminal air on computed tomography scan was found, this was not shown to be a risk factor for the clinical course.ConclusionPatients with type 1a acute diverticulitis can be treated successfully by conservative therapy in the majority of cases (85%). More research is required to define predictive factors for successful conservative management.  相似文献   
83.
It is unknown if solid organ transplant recipients are at higher risk for severe COVID-19. The management of a lung transplantation (LTx) program and the therapeutic strategies to adapt the immunosuppressive regimen and antiviral measures is a major issue in the COVID-19 era, but little is known about worldwide practice. We sent out to 180 LTx centers worldwide in June 2020 a survey with 63 questions, both regarding the management of a LTx program in the COVID-19 era and the therapeutic strategies to treat COVID-19 LTx recipients. We received a total of 78 responses from 15 countries. Among participants, 81% declared a reduction of the activity and 47% restricted LTx for urgent cases only. Sixteen centers observed deaths on waiting listed patients and eight centers performed LTx for COVID-19 disease. In 62% of the centers, COVID-19 was diagnosed in LTx recipients, most of them not severe cases. The most common immunosuppressive management included a decreased dose or pausing of the cell cycle inhibitors. Remdesivir, hydroxychloroquine, and azithromycin were the most proposed antiviral strategies. Most of the centers have been affected by the COVID-19 pandemic and proposed an active therapeutic strategy to treat LTx recipients with COVID-19.  相似文献   
84.

Rising incidence and mortality of cancer have led to an incremental amount of research in the field. To learn from preexisting data, it has become important to capture maximum information related to disease type, stage, treatment, and outcomes. Medical imaging reports are rich in this kind of information but are only present as free text. The extraction of information from such unstructured text reports is labor-intensive. The use of Natural Language Processing (NLP) tools to extract information from radiology reports can make it less time-consuming as well as more effective. In this study, we have developed and compared different models for the classification of lung carcinoma reports using clinical concepts. This study was approved by the institutional ethics committee as a retrospective study with a waiver of informed consent. A clinical concept-based classification pipeline for lung carcinoma radiology reports was developed using rule-based as well as machine learning models and compared. The machine learning models used were XGBoost and two more deep learning model architectures with bidirectional long short-term neural networks. A corpus consisting of 1700 radiology reports including computed tomography (CT) and positron emission tomography/computed tomography (PET/CT) reports were used for development and testing. Five hundred one radiology reports from MIMIC-III Clinical Database version 1.4 was used for external validation. The pipeline achieved an overall F1 score of 0.94 on the internal set and 0.74 on external validation with the rule-based algorithm using expert input giving the best performance. Among the machine learning models, the Bi-LSTM_dropout model performed better than the ML model using XGBoost and the Bi-LSTM_simple model on internal set, whereas on external validation, the Bi-LSTM_simple model performed relatively better than other 2. This pipeline can be used for clinical concept-based classification of radiology reports related to lung carcinoma from a huge corpus and also for automated annotation of these reports.

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85.
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   
86.
The objectives of this study were: i) to analyse the effects of morphine and naloxone on the rat's behaviour in the hot plate test using an ethological approach, and ii) to compare the effectiveness of repeated versus single test paradigms. Animals received either morphine (0, 3, 6 or 9 mg/kg SC) or naloxone (0, 0.01, 0.1 or 1 mg/kg SC). For repeated hot plate measures, rats were tested before and 60, 120, 180 and 240 min following morphine treatment, as well as 30, 60, 90 and 120 min after naloxone injection. For the single test schedule, rats were tested only once 60 min after morphine or 30 min after naloxone administration, or at 60, 120, 180, 240 and 300 min after 9 mg/kg morphine treatment. Behaviour was videotaped and analysed by an ethogram and ethological techniques. A cluster analysis revealed that the most frequently displayed patterns could be categorised into exploratory sniffing reactions (walk-sniff, immobile-sniff) and noxious-evoked elements, including primary (paw-licking, stamping), escape (jumping, leaning posture) and independent (hindleg-withdrawal) patterns. During repeated tests, morphine treatment induced: i) a maximum hypoalgesic effect 60 min post-injection (noxious-evoked patterns were significantly reduced), and ii) an unexpected thermal hyperreactivity rebound effect after 120 min (paw-licking and hindleg-withdrawal were enhanced), although changes in hindpaw-licking are more indicative of a hyperalgesic rebound effect. Most changes were quite similar during the single test schedule at 60 and 120 min after morphine injection. With regard to naloxone treatment, jumping latency was significantly decreased during the repeated test schedule, but not on single exposure to the plate. Other elements were facilitated, however, in the single test (stamping, leaning posture, hindleg-withdrawal). The results indicated that both repeated and single tests paradigms are of value for testing the effects of morphine and naloxone on rats. However, under our conditions the single test paradigm gave a better picture of the overall effects of the drug. Learning as well as habituation and sensitization may mask certain effects during repeated tests. In conclusion, an ethological analysis of the rat's behaviour in the hot plate test following administration of morphine and naloxone has been validated in this study.  相似文献   
87.
目的观察去甲硫氨酸全肠外营养对大鼠血清氨基酸谱等的影响.方法 Wistar大鼠24只,随机分为含甲硫氨酸(+MetTPN,n=12)和去甲硫氨酸全肠外营养2组(-MetTPN,n=12),分别给予相应的TPN支持.治疗7d后,每组随机抽取6只大鼠处死,检测血清FAA(HPLC法)、肝肾功能和全血常规,同时作心、肺、肝、肾组织病理学检查.两组其余大鼠继续原TPN治疗,观察生存期.结果 -MetTPN组大鼠血清游离Met、Cys明显降低,Asp、Glu、Ser等显著增高;大鼠体重下降;血清总蛋白和白蛋白水平下降;血常规和肾功能未见明显异常;组织学检查见肝细胞轻度肿胀,细胞核仁增粗,心肺肾未见明显异常;平均生存18d.对照组上述检查未见异常,除一只大鼠因导管并发症于TPN第16d死亡,其余大鼠全部存活.结论 -MetTPN一周可致大鼠血清游离Met、Cys明显降低和Asp、Glu、Ser等显著增高,及轻度肝功能改变;随着-MetTPN时间延长,出现严重的代谢紊乱和器官功能障碍导致死亡.  相似文献   
88.
Dysfunctions of the serotonergic system are implicated in psychiatric disorders, and there is evidence that a familial element may be significant in childhood autism. The concentrations of platelet 5-HT and free and total plasma tryptophan were determined in healthy pregnant women at each month of pregnancy and, at delivery, in both maternal and umbilical cord blood. A significant rise in the level of platelet 5-HT occured during month 3 and 4 followed by a retum to normal from month 5 until the delivery. The level of total plasma tryptophan remained equal to that in normal healthy non pregnant women until the 6th month. By month 7, it had decreased significantly and remained low until the month 9. At delivery the level fell significantly by –41%. The concentration of free tryptophan varied widely from one month to another but there was a trend towards a progressive increase from month 1 to 9, and at delivery the level returned to basal values. The concentration of 5-HT in the umbilical cord blood was about half that of the maternal blood. Inversely the concentrations of both free and total plasma tryptophan in the umbilical cord blood were nearly twice that of the maternal blood.
Zusammenfassung Dysfunktionen des serotoninergen Systems werden bei verschiedenen psychiatrischen Störungen angenommen, wobei es Hinweise für eine familiäre Komponente im Rahmen des kindlichen Autismus gibt. Die Konzentrationen der 5-Hydroxyindolessigsäure in Blutplättchen und des Tryptophans (freie und Gesamtplasmakonzentrationen) wurden in gesunden schwangeren Frauen sowohl im mütterlichen Blut als auch im Nabelschnurblut in jedem Schwangerschaftsmonat und bei der Geburt bestimmt. Ein signifikanter Anstieg der Konzentration der 5-Hydroxyindolessigsäure in Blutplättchen ereignete sich zwischen Mens III und IV, und von Mens V ab an bis zur Geburt normalisierte sich die Konzentration. Der Gesamtplasmaspiegel von Tryptophan glich dem in gesunden nicht-schwangeren Frauen bis zu Mens VI, in Mens VII war er signifikant abgefallen und blieb bis zur Mens IX niedrig. Zum Geburtstermin fiel der Spiegel signifikant um 41%. Die Konzentration des freien Tryptophans zeigte von Monat zu Monat deutliche Schwankungen, wobei es einen Trend in Richtung eines kontinuierlichen Anstiegs von Mens I–IX gab. Zum Termin fiel der Spiegel auf die basalen Werte ab. Die Konzentration der 5-Hydroxyindolessigsäure im Nabelschnurblut betrug ca. die Hälfte derer im maternalen Blut. Umgekehrt waren die Konzentrationen sowohl des freien als auch Gesamtplasmatryptophans im Nabelschnurblut ca. doppelt so hoch wie im maternalen Blut.

Résumé Le système sérotonergique semble impliqué dans les psychoses infantiles précoces, et, dans la mesure où une prévalence familiale existe pour ces affections, il nous a paru intéressant de déterminer un profil normal de la sérotonine (5-HT) plaquettaire et du tryptophane au cours de la gestation. Ceci dans le but de puvoir interpréter des résultats trouvés pendant la grossesse de femmes déjà mères d'un enfant psychotique. Nous avons déterminé les concentrations en 5-HT plaquettaire et en tryptophane plasmatique total et libre chez des femmes enceintes témoins à chaque mois de grossesse et, à l'accouchement, dans le sang maternel et dans le sang du cordon. La concentration en 5-HT plaquettaire augmente significativement aux 3ème et 4ème mois puis revient à la normale à partir du 5ème mois jusqu'à l'accouchement. Le tryptophane total est normal jusqu'au 6ème mois, il diminue significativement au 7ème mois et reste bas jusqu'au 9ème mois. A l'accouchement, il s'effondre (–41%). Le tryptophane libre varie beaucoup d'un mois à l'autre, il augmente progressivement du début à la fin de la grossesse, à l'accouchement par contre, il est normal. Dans le sang du cordon, la concentration en 5-HT est environ la moitié de celle du sang maternel, le tryptophane total et le tryptophane libre environ deux fois plus élevés.
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89.
Adenosine has a broad array of actions on neurons but astrocytes also possess adenosine receptors. We have previously shown that adenosine, by acting on astrocytes in the striatum, can modulate neuronal responses mediated by receptors coupled to phospholipase C through an astrocyto - neuronal interaction. In addition, adenosine was found to potentiate the alpha1-adrenergic production of inositol phosphates in astrocytes. The mechanism involved in this potentiation was further investigated by examining the effects of adenosine and alpha1-adrenergic receptor agonists on cytosolic Ca2+ in cultured striatal astrocytes from the embryonic mouse in primary culture. When used alone, methoxamine, a selective agonist of alpha-adrenergic receptors or 2-chloroadenosine, a stable analogue of adenosine, induced a transitory increase in cytosolic Ca2+, but their combined addition led to a sustained increase in cytosolic Ca2+, which seems to be due to a Ca2+ influx, because it was not observed in the absence of external Ca2+. Voltage independent Ca2+ channels contribute to this process and different blockers of voltage-operated calcium channels, such as dihydropyridines, phenylalkylamines, La3+ or Co2+ were ineffective in suppressing the sustained cytosolic Ca2+ elevation. Three observations suggest the implication of arachidonic acid in the observed potentiation: (i) arachidonic acid induced a sustained elevation of cytosolic Ca2+ similar to that evoked by the coapplication of methoxamine and 2-chloroadenosine; (ii) the addition of arachidonic acid during the calcic plateau produced by the combined application of the agonists did not increase further cytosolic Ca2+ levels; (iii) in the presence of methoxamine, 2-chloroadenosine induced a release of arachidonic acid. The stimulation of phospholipase C and the resulting activation of protein kinase C induced by methoxamine seem to be required for the potentiating effect of 2-chloroadenosine on cytosolic Ca2+. In fact, the direct activation of protein kinase C by an exogenous diacylglycerol analogue mimicked the effect of methoxamine because, in this condition, 2-chloroadenosine alone evoked a sustained elevation of cytosolic Ca2+. Therefore, methoxamine, through the successive activation of phospholipase C and protein kinase C, could allow a lipase, probably phospholipase A2, to be stimulated by 2-chloroadenosine. Arachidonic acid has already been shown to trigger the opening of K+ channels and the formation of inositol phosphates in other cell types. Therefore, in striatal astrocytes, 2-chloroadenosine, through an arachidonic acid-mediated hyperpolarization, could increase the Ca2+ driving force and thus improve Ca2+ influx through inositol phosphate-gated channels. This hypothesis is further supported by the suppressing effect of a 50 mM KCI-induced depolarization on the long lasting elevation of cytosolic Ca2+ seen in the combined presence of 2-chloroadenosine and methoxamine.  相似文献   
90.
PURPOSE: To analyze the management and clinical outcome of patients treated for a first isolated local recurrence of soft tissue sarcomas (trunk or extremities) and to identify prognosis factors. METHODS AND MATERIAL: Between 1980 and 1999, 83 adult patients were included in the study. Mean age was 61 years. Mean tumor size was 6 cm. Most sarcomas were located in extremities (n=74), were deep (n=60), and proximal (n=53); 30 involved nerves or vessels. Histologic subtypes were mainly grade 2 (42%) or 3 (36%) histiocytofibrosarcomas (49%) and liposarcomas (20%). Surgical treatment of recurrences consisted in wide excision (29 cases), marginal resection (43 cases), 5 patients requiring amputation. Final results were R0 (n=33), R1 (n=47) or R2 (n=3) resection. Besides surgery, 6 patients received neo-adjuvant and 7 others adjuvant chemotherapy. Twenty three patients received post-operative external beam radiotherapy (EBRT) (mean dose 55 Gy) and 26 interstitial 192Ir low dose rate brachytherapy (BCT) (mean dose 45 Gy for BCT alone, 22 Gy when associated with EBRT), 19 patients being re-irradiated. RESULTS: Mean follow up was 13 years. Thirty-seven (45%) patients relapsed, 62% of whom presenting an isolated local recurrence. Nineteen patients developed distant metastases. Multivariate analysis showed only tumor depth (P=0.05) and re-resection for primary R1 resection (P=0.018) being independent prognosis factors for tumor control, radiotherapy (EBRT and/or BCT) being significant in univariate analysis (P=0.05). Overall survival rate was 73%, 54%, and 47% at, respectively, 3.5 and 10 years, and was 65%, 35% and 32% after a further local recurrence. Multivariate analysis showed trunk (P=0.0001) or inferior extremity locations (P=0.023), symptomatic (P=0.001), high grade (P=0.01), deep (P=0.01) tumors, and the occurrence of a further local failure (P=0.004) as unfavorable characteristics for overall survival. CONCLUSIONS: A first isolated local recurrence of STS increases mainly the risk of a subsequent local relapse. Quality of local treatment is decisive. When a conservative treatment is feasible, it should combine surgical resection and radiotherapy, BCT being the best suited in previously irradiated patients. Efforts have to be pursued to increase quality of the treatment of primary tumors, at best performed in centers that have expertise in this field.  相似文献   
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