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1.
Perceptions of family cohesion and hierarchy structures were assessed by theFamily System Test (FAST), a clinically-derived figure placement technique. Parents (N=140) and their preadolescent offspring (N=70) completed typical and conflict representations in individual as well as group settings. Typical representations were characterized by balanced family structures (i.e. cohesive and moderately hierarchical) and those displaying conflict situations showed predominantly unbalanced patterns. FAST portrayals were related to respondent (mother vs. father vs. child). Fathers represented typical family relations as balanced more often than mothers. Regarding conflict representations, children were more likely than fathers to portray the family as unbalanced. However, analyses of representations of the same family (i.e. intra-family comparisons) indicated that all respondents differed in their perceptions and, that fathers' typical portrayals showed most often the same structure as those done by the family members as a group.  相似文献   
2.
Although a large part of the population suffers from allergies, a cure is not yet available. Allergen-specific immunotherapy (AIT) offers promise for these patients. AIT has proven successful in insect and venom allergies; however, for food allergy this is still unclear. In this editorial we focus on the recent advances in a proof of concept study in food allergy, FAST (Food allergy specific immunotherapy), which may increase interest within the biomolecular and pharmaceutical industry to embark on similar projects of immunology driven precision medicine within the allergy field.  相似文献   
3.
A replicated bidirectional selective breeding program has produced lines of mice that differ in locomotor response to ethanol (EtOH). FAST mice were bred for high locomotor activation, whereas SLOW mice were bred for low or depressed locomotor activity in response to 2.0 g/kg of EtOH. We tested FAST and SLOW mice for differences in sensitivity to the incoordinating (1.5 to 2.5 g/kg), hypothermic (3.0 g/kg), and sedative (4.0 g/kg) effects of EtOH, and for differences in sensitivity to withdrawal after acute and chronic EtOH exposure. SLOW mice were more ataxic in a grid test and developed greater tolerance than FAST mice at 2.0 g/kg of EtOH, were more hypothermic than FAST mice, and were more sensitive to the sedative effects of EtOH than FAST mice, as measured by latency to and duration of loss of righting reflex, and by blood ethanol concentrations at regain of the righting reflex. FAST mice had more severe withdrawal seizures after chronic exposure, but did not differ from SLOW mice in withdrawal severity after an acute injection of EtOH. These data suggest that FAST mice are generally more sensitive to central nervous system excitation, and SLOW mice are generally more sensitive to central nervous system sedation by EtOH, and further suggest genetic overlap with respect to genes that mediate locomotor responses to EtOH and genes determining sensitivity to EtOH-induced ataxia, hypothermia, sedation, and withdrawal severity after chronic exposure. Our current observations are in contrast to observations made earlier in selection, in which few line differences in sensitivity to EtOH effects other than locomotor activity were found. Thus, it seems that continued selection for differences in locomotor response to EtOH has produced genetically correlated differences in other EtOH responses.  相似文献   
4.
Fusion-associated small transmembrane (FAST) proteins are a diverse family of nonstructural viral proteins. Once expressed on the plasma membrane of infected cells, they drive fusion with neighboring cells, increasing viral spread and pathogenicity. Unlike viral fusogens with tall ectodomains that pull two membranes together through conformational changes, FAST proteins have short fusogenic ectodomains that cannot bridge the intermembrane gap between neighboring cells. One orthoreovirus FAST protein, p14, has been shown to hijack the actin cytoskeleton to drive cell-cell fusion, but the actin adaptor-binding motif identified in p14 is not found in any other FAST protein. Here, we report that an evolutionarily divergent FAST protein, p22 from aquareovirus, also hijacks the actin cytoskeleton but does so through different adaptor proteins, Intersectin-1 and Cdc42, that trigger N-WASP–mediated branched actin assembly. We show that despite using different pathways, the cytoplasmic tail of p22 can replace that of p14 to create a potent chimeric fusogen, suggesting they are modular and play similar functional roles. When we directly couple p22 with the parallel filament nucleator formin instead of the branched actin nucleation promoting factor N-WASP, its ability to drive fusion is maintained, suggesting that localized mechanical pressure on the plasma membrane coupled to a membrane-disruptive ectodomain is sufficient to drive cell-cell fusion. This work points to a common biophysical strategy used by FAST proteins to push rather than pull membranes together to drive fusion, one that may be harnessed by other short fusogens responsible for physiological cell-cell fusion.

Aquareovirus and orthoreovirus are two genera of the Reoviridae family of segmented double-stranded RNA viruses that form multinucleated syncytia after infection, which can increase viral spread and pathogenicity (14). To drive cell-cell fusion, both aquareovirus and orthoreovirus express a nonstructural, fusion-associated small transmembrane (FAST) protein on the plasma membrane of infected cells. The FAST protein is not required for viral entry, and expression of FAST protein alone is sufficient to cause cells to fuse with naïve neighboring cells, forming large multinucleated syncytium (1, 2, 512), confirming they are bona fide cell-cell fusogens. Although they have similar function and topology in the membrane, FAST proteins from aquareovirus and orthoreovirus share minimal sequence identity (13). Based on phylogenetic analysis, they are hypothesized to have evolved from a common, likely nonfusogenic, ancestor 510 million years ago (4, 13, 14). Separate gain-of-function events are believed to have produced fusogenic proteins in both aquareovirus and orthoreovirus, with further divergence or acquisition events resulting in the diversity of FAST proteins found in reoviruses today (13).Aquareovirus and orthoreovirus FAST proteins are single-pass membrane proteins of fewer than 200 residues comprised of a mostly disordered cytoplasmic tail, a transmembrane domain, and a small ectodomain of fewer than 40 residues (1, 2). The membrane-disruptive ectodomains of FAST proteins typically have solvent-exposed hydrophobic residues and/or myristoylation motifs that are necessary for cell-cell fusion (5, 1517). In contrast to other cell-cell fusogens that fuse membranes by pulling them together using conformational changes in their ∼10 nm-tall ectodomains, the ectodomains of FAST proteins have minimal predicted secondary structure, are unlikely to undergo conformational changes to drive membrane fusion (1, 2), and extend only ∼1 nm above the bilayer (5, 18). How such short fusogens can overcome the ∼2 nm repulsive hydration barrier and larger barrier presented by cell surface proteins to reach and fuse with an opposing membrane (5, 18) has been a long-standing question for FAST proteins and other short cell-cell fusogens, such as myomixer and myomaker that are involved in myoblast fusion (1922).Recently, we found that the FAST protein from reptilian orthoreovirus, p14, hijacks the host cell actin cytoskeleton to drive cell-cell fusion by forming localized branched actin networks (23). This is accomplished through a c-src phosphorylated tyrosine motif, YVNI, in p14’s disordered cytoplasmic tail that binds to a host adaptor protein, Grb2, which then binds to N-WASP and nucleates branched actin assembly. We hypothesize that this directly couples local actin-generated forces to push p14’s short, fusogenic ectodomain into the opposing cell’s plasma membrane (23). While all FAST family proteins have similarly short ectodomains, it is unclear if this is a general strategy used by other FAST proteins to drive cell-cell fusion.Here, we report that a FAST protein from the divergent aquareovirus, p22, also hijacks the host actin cytoskeleton but does so using a molecular strategy distinct from that of the orthoreovirus FAST protein p14. Instead of binding to Grb2, we find that p22 binds to Intersectin-1 through an SH3 binding motif in its cytoplasmic tail, which binds Cdc42 to activate N-WASP–mediated branched actin assembly. We show that despite minimal sequence identity, the p22 cytoplasmic tail can be functionally swapped with that of p14, suggesting that while the cytoplasmic tails of the two FAST proteins evolved independently, they serve a similar function. By directly coupling the ectodomain to a different actin nucleator, we suggest that actin’s functional role is applying mechanical pressure to a fusogenic ectodomain at the plasma membrane. This biophysical role may be shared across other members of the FAST protein family and could be more generally employed by other cell-cell fusogens.  相似文献   
5.

Objectives

This study is to present the diagnostic values of the novel sonographic visualization of the inferoposterior thoracic wall (VIP) and boomerang signs in detecting right pleural effusion by sonologists with little to no experience in ultrasound.

Methods

A prospective analysis of a convenience sample of patients who were assessed by junior intensive care physicians was performed. The patients all underwent computed tomography (CT) of the chest or abdomen with lung bases as part of their care regardless of indication; the results were interpreted by radiologists and were considered the gold standard. Sonography was performed to assess for the presence of the VIP and boomerang signs. Sonographic and chest radiographic findings were compared against CT results.

Results

73 patients were enrolled. The sensitivity and specificity for the VIP sign were 0.85 (95% confidence interval [CI], 0.67–0.94) and 0.86 (95% CI, 0.70–0.95). The sensitivity and specificity for the boomerang sign were 0.78 (95% CI, 0.60–0.90) and 0.87 (95% CI, 0.71–0.95). However, the sensitivity and specificity for the traditional approach of detecting an anechoic collection above the diaphragm to indicate pleural effusion were only 0.54 (95% CI, 0.37–0.71) and 0.86 (95% CI, 0.80–0.99).

Conclusions

Despite inexperience in sonography, the novel VIP and boomerang signs show high diagnostic values in detecting right pleural effusion compared to the traditional methods.  相似文献   
6.
7.

Background

Heart-type fatty acid-binding protein (H-FABP) is a useful biomarker for risk stratification of patients with pulmonary embolism (PE). In patients with acute myocardial infarction, H-FABP plasma concentrations rise after 30 minutes and return to normal within 20-24 hours. We tested whether the predictive value of H-FABP is affected by the duration of symptoms prior to diagnosis in patients with PE.

Material and Methods

We prospectively studied 257 consecutive normotensive patients with confirmed symptomatic PE.

Results

Patients with acute (< 24 hours; n = 150) symptom onset presented more often with syncope (28.7% vs. 6.5%; p < 0.001) compared to patients with symptoms ≥ 24 hours (n = 107); other baseline characteristics, comorbidities, and risk factors were distributed equally. Patients with an adverse 30-day outcome (6.6%) had higher H-FABP levels (11.84 [3.57-19.62] ng/ml) compared to patients with a favorable course (3.42 [1.92-5.42] ng/ml; p < 0.001). However, the proportion of patients with H-FABP levels ≥ 6 ng/ml did not differ among patients with acute symptom onset and late presentation (p = 0.104). Only tachycardia and elevation of H-FABP were associated with an increased risk of an adverse 30-day outcome both in patients with acute symptom onset (H-FABP: OR, 5.8; 95% CI, 1.4-24.5; p = 0.016; tachycardia: 7.0 [1.4-36.0]; p = 0.018) and late presentation (H-FABP: 9.3 [2.0-43.2]; p = 0.004 and tachycardia: 12.3 [1.5-103.6]; p = 0.021). The prognostic value could further be improved by the use of a simple H-FABP-based clinical prediction score.

Conclusions

Our findings indicate that H-FABP is a useful biomarker for risk stratification of normotensive patients with PE regardless of symptom duration prior to diagnosis.  相似文献   
8.
9.
This report describes the discovery and characterization of a new fusogenic orthoreovirus, Broome virus (BroV), isolated from a little red flying-fox (Pteropus scapulatus). The BroV genome consists of 10 dsRNA segments, each having a 3′ terminal pentanucleotide sequence conserved amongst all members of the genus Orthoreovirus, and a unique 5′ terminal pentanucleotide sequence. The smallest genome segment is bicistronic and encodes two small nonstructural proteins, one of which is a novel fusion associated small transmembrane (FAST) protein responsible for syncytium formation, but no cell attachment protein. The low amino acid sequence identity between BroV proteins and those of other orthoreoviruses (13-50%), combined with phylogenetic analyses of structural and nonstructural proteins provide evidence to support the classification of BroV in a new sixth species group within the genus Orthoreovirus.  相似文献   
10.
目的研究FAST(FocussedAssessmentSonographTrauma)超声检查法对腹部创伤的初步诊断价值。方法对46例伴有腹部创伤的多发伤病人进行FAST超声检查,以探及腹腔游离液体为阳性发现,并以随后进行的腹部CT检查或手术探查结果作为标准进行敏感性和特异性分析。结果46例病人经CT检查或手术证实肝脾肾损伤共13例,FAST超声检查结果阳性发现共15例,敏感性为76.9%、特异性为84.8%。结论FAST超声检查法可以作为判断腹部创伤病人是否存在腹腔出血的初步检查方法。  相似文献   
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