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PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.  相似文献   
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目的:探讨单孔胸腔镜下肺癌手术术后胸腔引流时间的影响因素。方法:本研究采用回顾性分析方法,回顾我院2018年01月至2019年12月原发性肺癌患者经单孔胸腔镜手术治疗的病例199例。按照术后胸腔引流时间分为两组,Ⅰ组(术后胸腔引流时间<5天)和Ⅱ组(术后胸腔引流时间≥5天)。对于影响术后胸腔引流时间的可能因素在两组间先采用单因素分析的方法筛选,再将筛选出来的对术后胸腔引流时间可能有意义的影响因素进行二项Logistic多因素回归分析。结果:经单因素分析及二项Logistic多因素回归分析结果显示:年龄≥60岁、手术部位、肺段切除术、胸膜粘连、手术时间≥180 min、术后早期下床活动是术后胸腔引流时间的独立影响因素(P<0.05)。结论:对于具有多个延长术后胸腔引流时间的独立影响因素的患者,应制定个体化管理方案,尽可能减少术后胸腔引流时间,减少住院天数,加快患者康复。  相似文献   
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《Revue neurologique》2022,178(8):812-816
IntroductionAs an immune-mediated disease of the central nervous system, multifaceted aspects of a humoral immune response are widely described during multiple sclerosis (MS). However, the prevalence of different auto-antibodies, such as antinuclear antibodies (ANA), during MS is very variable and their clinical relevance remains controversial. Our aim was to evaluate the prevalence and clinical correlations of ANA positivity in South Tunisian MS patients.Material and methodsWe performed ANA screening using indirect immunofluorescence (IIF) on HEp-2 cells (Biosystems®) in 82 MS patients. For ANA positive samples (titer ≥1/160), anti-ds-DNA detection (IIF on Crithidia luciliae (Biosystems®)) and extractable nuclear antigen typing (immunodot (Euroimmun®)) were performed.ResultsANA were positive in 35/82 MS patients (42.7%). The titer was ≥ 1/320 in 16/35 patients. The antigenic specificity of ANA was identified in 7/35 patients. None of the patients had extra-neurological manifestations. No correlation was found between ANA and age, gender, MS course, disease duration, disability, annual relapse rate nor IgG index. ANA positivity was more frequent in patients with IgG oligoclonal bands (OCB) (47.1%) than in patients without IgG OCB (16,6%) (p = 0.049). Regarding disease activity, ANA positivity was significantly more frequent in patients with relapse (52.6%) than in patients in remission (25.9%) (p = 0.031).ConclusionOur results showed that ANA positivity in MS disease is not rare. This positivity was not associated with clinical expression of any connective tissue disease. ANA occurrence in MS was associated with IgG OCB+ profile and relapsing status, probably reflecting an ongoing immune dysregulation.  相似文献   
6.
Purpose: Spray-freeze drying (SFD) is a recently applied method to develop pharmaceutical powders. This study aimed to analyze the competence of Trehalose, Mannitol, Lactose, and Sorbitol instability and aerosolization of Immunoglobulin G (IgG) via SFD.

Methods: Induced soluble aggregates were quantified at 0 and 3?months, and 45?°C using size-exclusion chromatography. Conformation and thermogravimetric assessments were done by Fourier transform infrared spectroscopy and differential scanning calorimetry. Laser light scattering was performed to determine the particle sizes. Aerodynamic features were characterized by twin stage impinger and scanning electron microscopy.

Results: Although sugars/polyols preferably stabilized IgG following the process, storage stabilization was achieved in Trehalose, Trehalose-Lactose, Lactose, and Trehalose-Mannitol-based powders with soluble aggregates <5%. The conformation of antibody was preserved with β sheet content from 66.28% to 76.37%. Particle sizes ranged from 5.23 to 8.12?µm. Mannitol exhibited the best aerodynamic behavior, fine particle fraction (FPF: 70%) but high degree of protein aggregation during storage.

Conclusions: SFD could favorably stabilize antibody using Trehalose and its combination with Lactose and Mannitol, and also, Lactose alone. Sorbitol disturbed IgG powder recovery. Incorporation of other types of excipient is required for efficient respiratory delivery of IgG molecules.  相似文献   

7.
Chronic spontaneous urticaria (CSU) pathogenesis shows a complex and still unclear interplay between immunoglobulin (Ig)G- and IgE-mediated autoimmunity, leading to mast cell and basophil degranulation and wheal formation. The objective of this study was to evaluate at the same time IgE- and IgG-reactivity to well recognized and recently reported autoantigens in CSU patients, and to assess the effects of such reactivity on response to the anti-IgE monoclonal antibody omalizumab. Twenty CSU patients underwent omalizumab treatment. Urticaria activity score 7 (UAS7) was recorded at baseline and at different drug administration time-points for categorizing early-, late- or non-responders. At baseline, sera from the 20 patients and from 20 controls were tested for IgE and IgG autoantibodies to high- and low-affinity IgE receptors (FcεRI and FcεRII), tissue factor (TF) and thyroglobulin (TG) by immunoenzymatic methods. Antibody levels were compared with those of controls and analysed according to response. Eighteen patients were omalizumab responders (11 early and seven late), while two were non-responders. More than 50% of patients had contemporary IgE and IgG to at least to one of the four different autoantigens. Late responders showed higher levels of both anti-TF IgE and IgG than early responders (P = 0·011 and P = 0·035, respectively). Twenty-five per cent of patients had levels of anti-FcεRI IgE, exceeding the upper normal limit, suggesting that it could be a novel auto-allergen in CSU. In CSU, there is an autoimmune milieu characterized by the co-existence of IgE and IgG autoantibodies to the same antigen/allergen, particularly in late responders to omalizumab, possibly explaining the slower response.  相似文献   
8.
Staphylococcus aureus sepsis developed in a 14 year old girl. Immunological evaluation revealed low level of IgG3, although total IgG level was normal. The level of IgG3 increased gradually along with the recovery from sepsis. Immunoglobulin replacement therapy might have been useful in this patient, even though the total immunoglobulin level was within normal limits.  相似文献   
9.
2000年广西麻疹疑似病例血清学监测分析   总被引:3,自引:1,他引:2  
目的了解麻疹的血清流行病学特征 ,探讨麻疹与风疹之间的血清学鉴别诊断。方法采用酶联免疫吸附法对714例RFIs的血清标本进行麻疹IgM和风疹IgM抗体检测 ,对204例麻疹IgM抗体阳性的血清标本进行麻疹IgG抗体检测。结果麻疹IgM阳性率为45.7 % ,风疹IgM抗体阳性率为27.5%。在出疹后4~14天采集的血清标本其麻疹IgM和风疹IgM抗体阳性检出率最高。麻疹IgM阳性数以1~14岁为主 ,1~6岁最高 (44.5% ) ,风疹IgM阳性数是7~14岁为最高 (73.5% ) ;麻疹IgG检出<1:200为76例 (27.7 % ) ,1:200为59例 (21.5% ) ,1:800为17例(6.2 %) ,1:3200为25例(9.1 %) ,≥1:12800为27例(9.8 %)。结论采血时间与检出率密切相关 ;采集血清标本要注意质量和采集时间 ;麻疹患者与风疹患者有一定的年龄差距 ,风疹是最主要的需要与麻疹相鉴别的RFIs,未经实验室诊断极易发生误诊 ;应提高麻疹实验室诊断的及时性、准确性和敏感性 ,建议有条件的地区开展麻疹抗体血清学检测  相似文献   
10.
We have devised assays to detect both circulating alloantibodies to platelets (indirect assay) and platelet-association IgG and IgM (direct assay) using a flow cytometric technique. A variety of patients with immune thrombocytopenia were studied. Employment of a confocal lens in the flow cytometer increased the discrimination power of the instrument. Patients with autoimmune thrombocytopenia (idiopathic thrombocytic purpura [ITP], systemic lupus erythematosus (SLE), lymphoma, leukemia, and drug-induced thrombocytopenia showed a significant increase in platelet-associated antibody. Circulating antibodies to platelets (alloantibodies) were demonstrated in cases of platelet refractoriness and neonatal isoimmune purpura. Day-today precision of the assays ranged from 3% to 6% (coefficient of variation). No interference was shown in the presence of hemoglobin (5 g/L), triglycerides (10 g/L), or polyclonal and monoclonal immunoglobulinemia (50 g/L: IgG, IgA, IgM). The sensitivity of the direct assay was 500 attograms of IgG or IgM platelet.  相似文献   
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