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31.
Priyanka Jha Liina Pder Charis Bourgioti Nishat Bharwani Sara Lewis Amita Kamath Stephanie Nougaret Philippe Soyer Michael Weston Rosa P. Castillo Aki Kido Rosemarie Forstner Gabriele Masselli 《European radiology》2020,30(5):2604-2615
This study was conducted in order to establish the joint Society of Abdominal Radiology (SAR) and European Society of Urogenital Radiology (ESUR) guidelines on placenta accreta spectrum (PAS) disorders and propose strategies to standardize image acquisition, interpretation, and reporting for this condition with MRI. The published evidence-based data and the opinion of experts were combined using the RAND–UCLA Appropriateness Method and formed the basis for these consensus guidelines. The responses of the experts to questions regarding the details of patient preparation, MRI protocol, image interpretation, and reporting were collected, analyzed, and classified as “recommended” versus “not recommended” (if at least 80% consensus among experts) or uncertain (if less than 80% consensus among experts). Consensus regarding image acquisition, interpretation, and reporting was determined using the RAND–UCLA Appropriateness Method. The use of a tailored MRI protocol and standardized report was recommended. A standardized imaging protocol and reporting system ensures recognition of the salient features of PAS disorders. These consensus recommendations should be used as a guide for the evaluation of PAS disorders with MRI.
• MRI is a powerful adjunct to ultrasound and provides valuable information on the topography and depth of placental invasion.
• Consensus statement proposed a common lexicon to allow for uniformity in MRI acquisition, interpretation, and reporting of PAS disorders.
• Seven MRI features, namely intraplacental dark T2 bands, uterine/placental bulge, loss of low T2 retroplacental line, myometrial thinning/disruption, bladder wall interruption, focal exophytic placental mass, and abnormal vasculature of the placental bed, reached consensus and are categorized as “recommended” for diagnosing PAS disorders. 相似文献
32.
Zuberbier T Bindslev-Jensen C Canonica W Grattan CE Greaves MW Henz BM Kapp A Kozel MM Maurer M Merk HF Schäfer T Simon D Vena GA Wedi B;EAACI/GALEN/EDF 《Allergy》2006,61(3):316-320
This guideline is the result of a consensus reached during a panel discussion at the 2nd International Consensus Meeting on Urticaria, Urticaria 2004, a joint initiative of the European Academy of Allergology and Clinical Immunology Dermatology Section and the European Union (EU)-funded network of excellence, GA2LEN. It covers the definition and classification of urticaria, taking into account the recent progress in identifying causes, eliciting factors and pathomechanisms of this disease. We have outlined useful diagnostic approaches for different subtypes of urticaria. This guideline was, in addition, accepted by the European Dermatology Forum (EDF) and was formally approved by the European Union of Medical Specialists (UEMS). 相似文献
33.
34.
Background
Pancreatic neuroendocrine tumors (PNETs) are a characteristic feature of the tumor syndromes multiple endocrine neoplasia type 1 (MEN-1) and von Hippel-Lindau disease (VHL). With VHL, about 10% of the patients exhibit PNETs by age 40 years. Metastatic potential is high if the tumors have grown to >3 cm in diameter. Optimal surgical treatment is still a challenge. 相似文献35.
Dominik Schori Matthias Jaeger Timon Elmer Susanne Jaeger Candelaria Mahlke Kolja Heumann Anastasia Theodoridou Gianfranco Zuaboni Bernd Kozel Franziska Rabenschlag 《Archives of Psychiatric Nursing》2018,32(5):662-669
Treatment pressure restricts patients' voluntary and autonomous decisions. Yet interventions involving treatment pressure are widely used in mental health and psychosocial services. This cross-sectional study explored whether mental health professionals' knowledge on five types of treatment pressure (no coercion, persuasion or conviction, leverage, threat, and formal coercion) was associated with sociodemographic, professional and contextual factors. A more positive attitude towards interventions involving treatment pressure was associated with underrating the level of those interventions compared with a predefined default value. The treatment setting and professional group played a minor role in ‘leverage’ and ‘formal coercion’ types of treatment pressure, respectively. 相似文献
36.
Astuti D Hart-Holden N Latif F Lalloo F Black GC Lim C Moran A Grossman AB Hodgson SV Freemont A Ramsden R Eng C Evans DG Maher ER 《Clinical endocrinology》2003,59(6):728-733
BACKGROUND: Germline mutations in three subunits of mitochondrial complex II (SDHB, SDHC and SDHD) may be associated with susceptibility to phaeochromocytoma (PC) and/or head and neck paraganglioma (HNPGL). METHODS: To further define the role of SDH subunit mutations in these disorders, we analysed a series of 22 probands with PC and evidence of genetic susceptibility (seven with familial PC only, one with familial PC and HNPGL, 10 sporadic cases with multiple PC and four cases of isolated paediatric onset PC) for germline SDHB, SDHC and SDHD mutations. In addition, we analysed 34 cases of HNPGL (30 isolated cases with single tumours, three isolated cases with multiple tumours and one familial case with multiple tumours) for somatic and germline mutations in SDHB, SDHC and SDHD. RESULTS: We identified four germline mutations (three SDHB and one SDHD, three novel) in the 22 PC probands. Combining these results with our previous series, we have detected germline SDHB or SDHD mutations in 2/12 (17%) of familial PC only kindreds, 4/5 (80%) of familial PC and HNPGL cases, 1/10 of sporadic multiple PC cases and 2/4 (50%) of paediatric PCs. No somatic mutations were detected in the HNPGL tumours, but four cases with multiple HNPGL had the common P81L germline SDHD mutation. Intriguingly a silent SNP (c.204C > T) in SDHD was significantly more common in HNPGL cases (6/34) than in controls (1/100, P = 0.0011). Combining our results with those from two other large studies in which both SDHB and SDHD have been analysed, SDHB mutations were most commonly associated with phaeochromocytoma susceptibility and SDHD with the development of HNPGL (P = 0.025). However, germline SDHB and SDHD mutations demonstrate considerable phenotypic variability and genotype-phenotype correlations are complex. CONCLUSION: The significantly lower frequency (P = 0.028) of germline SDH subunit mutations in familial PC only cases compared to those with familial PC and HNPGL suggests that further PC susceptibility gene(s) remain to be identified. 相似文献
37.
Thomas R. Kozel Bouke C. H. deJong Matthew M. Grinsell Randall S. MacGill Kevin K. Wall 《Infection and immunity》1998,66(4):1538-1546
Incubation of the encapsulated yeast Cryptococcus neoformans in human serum leads to alternative pathway-mediated deposition of C3 fragments in the capsule. We examined the ability of monoclonal antibodies (MAbs) specific for different epitopes of the major capsular polysaccharide to alter the kinetics for classical and alternative pathway-mediated deposition of C3 onto a serotype A strain. We studied MAbs reactive with capsular serotypes A, B, C, and D (MAb group II); serotypes A, B, and D (MAb group III); and serotypes A and D (MAb group IV). The MAb groupings are based on antibody variable region usage which determines the antibody molecular structure. When both the classical and alternative pathways were operative, group II MAbs induced early classical pathway-mediated binding of C3 but reduced the overall rate of C3 accumulation and the amount of bound C3. Group III MAbs closely mimicked the effects of group II MAbs but exhibited reduced support of early classical pathway-facilitated accumulation of C3. Depending on the antibody isotype, group IV MAbs slightly or markedly enhanced early binding of C3 but had no effect on either the rate of C3 accumulation or the amount of bound C3. When the classical pathway was blocked, group II and III MAbs markedly suppressed C3 binding that normally would have occurred via the alternative pathway. In contrast, MAbs of group IV had no effect on alternative pathway-mediated C3 binding. These results indicate that anticapsular antibodies with different epitope specificities may have distinct regulatory effects on activation and binding of C3.Cryptococcus neoformans is the etiological agent of cryptococcal meningitis, a life-threatening infection of particular importance in patients with deficiencies in cellular immunity, most notably patients with the AIDS. The yeast is surrounded by a polysaccharide capsule that is composed primarily of glucuronoxylomannan (GXM), which has a linear (1→3)-α-d-mannopyranan backbone bearing β-d-xylopyranosyl, β-d-glucopyranosyluronic acid, and O-acetyl substituents (3, 9, 54). The cryptococcal capsule occurs as four major serotypes (A, B, C, and D) and is an essential virulence factor for the yeast.One of the most striking features of the cryptococcal capsule is its ability to activate the alternative complement pathway. Incubation of encapsulated cryptococci in normal human serum (NHS) leads to the deposition of 107 to 108 C3 fragments on the yeast (28, 56). The C3 is deposited at the surface and throughout the capsule (30). Available evidence indicates that the amount of anti-GXM antibodies found in NHS is not sufficient to initiate the classical pathway (24); consequently, activation and binding of C3 to the cryptococcal capsule are mediated entirely by the alternative complement pathway (29, 30, 55). One of the hallmark features of alternative pathway deposition of C3 onto encapsulated cryptococci is a delay of 5 to 8 min before readily detectable amounts of C3 are found on yeast cells incubated in NHS (29, 55). Once past the initial lag, C3 fragments rapidly accumulate on the yeast cells as incubation proceeds for an additional 10 min.Recently, there has been interest in antibody-mediated resistance to cryptococcosis. Monoclonal antibodies (MAbs) have been proposed for treatment of cryptococcosis (7), and immunization with GXM-protein conjugates has been suggested for prevention of cryptococcosis (6, 12, 13). However, it is becoming increasingly clear that anti-GXM MAbs may have distinct specificities and biological activities. Anti-GXM MAbs which differ in (i) reactivities with GXM of the four major serotypes (2), (ii) apparent binding sites in the cryptococcal capsule (32, 37), and (iii) abilities to provide protection in a murine model of cryptococcosis (32, 37) have been described. Some differences in biological activity are related to differences in the epitope specificities of the various MAbs (32, 37).One means by which antibodies could enhance resistance to cryptococcosis is through accelerated deposition of opsonic C3 fragments via the action of the classical pathway. Such an acceleration would reduce or eliminate the 5- to 8-min lag that occurs during alternative pathway-mediated deposition of C3 fragments. The objectives of our study were to evaluate the effects of anti-GXM MAbs on the kinetics and sites for deposition of C3 fragments into the cryptococcal capsule. We examined several well-characterized antibodies that differed in the epitope specificity of the MAbs. The results showed that MAbs with different isotypes and epitope specificities had distinctly different effects on activation and binding of C3 via the classical and alternative pathways; many antibodies markedly suppressed C3 binding, some antibodies accelerated C3 binding, and other antibodies had little or no effect. 相似文献
38.
Candida albicans activates the classical and alternative complement pathways, leading to deposition of opsonic complement fragments on the cell surface. Our previous studies found that antimannan immunoglobulin G (IgG) in normal human serum (NHS) allows C. albicans to initiate the classical pathway. The purpose of this study was to determine whether antimannan IgG also plays a role in initiation of the alternative pathway. Pooled NHS was rendered free of classical pathway activity by chelation of serum Ca2+ with EGTA alone or in combination with immunoaffinity removal of antimannan antibodies. Kinetic analysis revealed a 6-min lag in detection of C3 binding to C. albicans incubated in EGTA-chelated NHS, compared to a 12-min lag in NHS that was both EGTA chelated and mannan absorbed. The 12-min lag was shortened to 6 min by addition of affinity-purified antimannan IgG. The accelerating effect of antimannan IgG on alternative pathway initiation was dose dependent and was reproduced in a complement binding reaction consisting of six purified proteins of the alternative pathway. Both Fab and F(ab′)2 fragments of antimannan IgG facilitated alternative pathway initiation in a manner similar to that observed with intact antibody. Immunofluorescence analysis showed that addition of antimannan IgG to EGTA-chelated and mannan-absorbed serum promoted an early deposition of C3 molecules on the yeast cells but had little or no effect on distribution of the cellular sites for C3 activation. Thus, antimannan IgG antibodies play an important regulatory role in interactions between the host complement system and C. albicans.Candida albicans activates the human complement system via both the classical and alternative pathways, leading to deposition of opsonic complement fragments on the yeast cell surface (19, 21, 40). A naturally occurring antimannan immunoglobulin G (IgG) is required for activation of the classical pathway by C. albicans yeast cells incubated in normal human serum (NHS) (21, 40). C3 deposition via the antimannan IgG-dependent classical pathway occurs rapidly and can be detected within 1 min following incubation of the yeast cells with NHS (40). Moreover, initial C3 molecules bound through the classical pathway are uniformly distributed over the entire yeast cell surface (21, 40). C3 deposition through the alternative pathway exhibits distinctly different characteristics. If the classical pathway of NHS is blocked by either treatment with the Ca2+ chelator EGTA (21, 40) or mannan absorption to remove antimannan IgG (40), deposition of initial C3 molecules occurs at a few discrete sites on the yeast cell surface. Furthermore, deposition of initial C3 molecules via the alternative pathway requires a much longer incubation time than C3 binding through the antimannan IgG-dependent classical pathway. For example, if the classical pathway is blocked by treatment of serum with EGTA, there is a 6-min delay before readily detectable amounts of C3 accumulate on the yeast cells; if the classical pathway is blocked by absorption of NHS with mannan to remove initiating antibody, the delay is extended to 12 min (40).Our interest has focused on the observed difference in the time required for C3 accumulation via the alternative pathway on C. albicans yeast cells incubated in EGTA-chelated serum versus mannan-absorbed serum. One explanation is that mannan absorption of serum reduced the activity of one or more of proteins that are involved in the alternative pathway. This possibility appears unlikely because addition of affinity-purified antimannan IgG to mannan-absorbed serum restores characteristic C3 binding kinetics to levels observed in intact serum (40). Alternatively, the naturally occurring antimannan IgG that is present in EGTA-chelated NHS may facilitate C3 deposition via the alternative pathway.Antibody-dependent activation of the alternative pathway has been described for several particulate activators. Ratnoff et al. (31) identified three models that have been used to demonstrate antibody-dependent activation of the alternative pathway: (i) experiments done in the presence of EGTA which chelates Ca2+ and thereby prevents activation of C1, (ii) experiments done with purified proteins of the alternative pathway, and (iii) experiments done with sera that are genetically deficient in C4 or C2. Using one or more of these experimental approaches, studies with bacteria, protozoa, virus-infected cells, erythrocytes, cross-linked dextran, and zymosan have shown that antibodies can facilitate activation of the alternative pathway by some particles. The role of antibodies in alternative pathway initiation has not been studied with C. albicans or other pathogenic fungi.The objectives of this report were to determine whether antimannan IgG in NHS influences alternative pathway-mediated deposition of C3 onto C. albicans yeast cells and to determine the molecular components of IgG molecules that are involved in this process. Our results show that (i) very little deposition of C3 occurs in the absence of antimannan IgG, (ii) antimannan IgG accelerates alternative pathway initiation in a dose-dependent manner, and (iii) alternative pathway initiation is facilitated by both Fab and F(ab′)2 fragments of antimannan IgG. 相似文献
39.
Debbie J. Marsh Patricia L. M. Dahia Valrie Coulon Zimu Zheng Franoise Dorion-Bonnet Katherine M. Call Randall Little Albert Y. Lin Rosalind A. Eeles Alisa M. Goldstein Shirley V. Hodgson Anne-Louise Richardson Bruce G. Robinson H. Christian Weber Michel Longy Charis Eng 《Genes, chromosomes & cancer》1998,21(1):61-69
40.
Markoulaki D Kostikas K Papatheodorou G Koutsokera A Alchanatis M Bakakos P Gourgoulianis KI Roussos C Koulouris NG Loukides S 《European Journal of Internal Medicine》2011,22(1):103-107