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11.
Amitai  Marianne M.  Klang  Eyal  Levartovsky  Asaf  Rozendorn  Noa  Soffer  Shelly  Taha  Gadeer Ali  Ungar  Bella  Greener  Tomer  Ben-Horin  Shomron  Eliakim  Rami  Kopylov  Uri 《Abdominal imaging》2018,43(12):3207-3212
Background and aims

Distinguishing between fibrotic and inflammatory strictures in Crohn’s disease (CD) is still challenging. The capacity of diffusion-weighted (DWI) magnetic resonance (MRE) to identify intestinal fibrosis was recently demonstrated; however, the therapeutic implications of this association have never been evaluated. The aim of the current study was to identify imaging features, including DWI, which can predict response to anti-inflammatory treatment in patients with stricturing CD.

Methods

Consecutive CD patients with intestinal strictures that initiated treatment with anti-tumor necrosis alpha (anti-TNF) between June 2012 and April 2017 with MRE adjacent to treatment onset were retrospectively collected. The primary outcome was treatment failure, defined as drug discontinuation, CD-related surgery, or endoscopic dilatation of the stricture. Clinical, demographic, and imaging data were compared between patients who did and did not develop treatment failure within 12 months of anti-TNF treatment initiation.

Results

A total of 21 patients were included in the study; 9/21 (42.8%) developed treatment failure. None of the clinical/demographic parameters were associated with the risk of treatment failure. Among imaging parameters, only ADC value (< 1 × 10−3 mm2/s) was significantly associated with the risk of treatment failure (AUC = 0.81, 66% vs. 0%, p = 0.015).

Conclusions

Our results suggest that ADC value on DWI MRE may predict the risk of treatment failure in stricturing CD. If replicated in larger studies, these results may guide therapeutic decisions and suggest avoiding anti-TNF treatment.

  相似文献   
12.
The present study is the first to assess whether the neural correlates of cognitive control processes differ in adults with and without a behaviorally inhibited temperament during early childhood. Adults with and without childhood behavioral inhibition completed an emotional conflict task while undergoing functional magnetic resonance imaging scanning. While no group differences in behavior were observed, adults with childhood behavioral inhibition, relative to adults without childhood behavioral inhibition, exhibited greater dorsomedial prefrontal cortex activity during conflict detection and greater putamen activity during conflict adaptation. Lifetime psychopathology predicted behavioral, but not brain-related, differences in conflict adaptation. These data suggest that the brain regions underlying cognitive control processes are differentially influenced by childhood behavioral inhibition, and may be differently related to psychopathology.  相似文献   
13.
The International Journal of Cardiovascular Imaging - Pulmonary hypertension (PH) is often diagnosed late in the disease course. As many patients may undergo computed tomography pulmonary...  相似文献   
14.
15.
Surfactant protein-D (SP-D), a member of the "collectin" family, has been shown to play a role in innate immunity through modulation of inflammation and clearance of organisms. The role of SP-D in host defense against Pneumocystis carinii pneumonia was assessed using SP-D knockout (KO) mice. When inoculated with P. carinii, both wild-type (wt) and SP-D KO mice required CD4 cell depletion to develop infection. In CD4 cell-depleted models, 2 weeks after infection with P. carinii, SP-D KO mice developed increased intensity of infection, compared with wt mice, despite higher lung-inflammation scores and increased amounts of alveolar inflammatory cells. The increased inflammation seen in SP-D KO mice was accompanied by increases in lung weight, expression of inducible nitric oxide (NO) synthase, total NO levels, and 3-nitrotyrosine levels in lung tissue. These results indicate that SP-D plays a role in host defense against P. carinii in vivo by modulating clearance of organisms, lung inflammation, and metabolism of NO.  相似文献   
16.
We compared EUCAST and CLSI antifungal susceptibility testing (AFST) methods for triazoles and amphotericin B against 124 clinical Mucorales isolates. The EUCAST method yielded MIC values 1- to 3-fold dilutions higher than those of the CLSI method for amphotericin B. The essential agreements between the two methods for triazoles were high, i.e., 99.1% (voriconazole), 98.3% (isavuconazole), and 87% (posaconazole), whereas it was significantly lower for amphotericin B (66.1%). Strategies for harmonization of the two methods for Mucorales AFST are warranted.  相似文献   
17.
Perioperative infection is the most common and dreaded complication associated with tissue expander (TE) breast reconstruction. Historically, the expansion period was thought to be the time of greatest hazard to the implant. However, recent institutional observations suggest infectious complications occur prior to expansion. This investigation, therefore, was conducted to determine the timing of infectious complications associated with two‐stage TE breast reconstructions. Following IRB approval, a retrospective review of all consecutive two‐stage immediate TE breast reconstructions at a single institution from November 2007 to November 2011 was conducted. Reconstructions were then divided into two cohorts: those suffering infectious complications and those that did not. Infectious complications including minor cellulitis, major cellulitis, abscess drainage, and explantation were identified. Various operative and patient variables were evaluated in comparison. Eight hundred ninety immediate two‐stage TE breast reconstructions met inclusion criteria. Patients suffering infection were older (55.4 years versus 49.3 years; p < 0.001), and more likely to have therapeutic mastectomy (94% versus 61%; p < 0.0001), the use of acellular dermal matrix (ADM; 72.5% versus 54.9%; p = 0.001), and greater initial TE fill (448.6 mL versus 404.7 mL; p = 0.0078). The average time to developing of infectious symptoms was 29.6 days (range 9–142 days), with 94.6% (n = 87) of infections prior to the start of expansion. Perioperative infections in immediate two‐stage TE to implant breast reconstructions are significant and occur mostly prior to the start of expansion. Thus, challenging the conventional wisdom that instrumentation during expander filling as the primary cause of implant infections. Possible etiologic factors include greater age, therapeutic mastectomy versus prophylactic mastectomy, larger initial TE fill, and the use of ADM.  相似文献   
18.
Neuronal calcium (Ca2+)-binding proteins 1 and 2 (NECAB1/2) are members of the phylogenetically conserved EF-hand Ca2+-binding protein superfamily. To date, NECABs have been explored only to a limited extent and, so far, not at all at the spinal level. Here, we describe the distribution, phenotype, and nerve injury-induced regulation of NECAB1/NECAB2 in mouse dorsal root ganglia (DRGs) and spinal cord. In DRGs, NECAB1/2 are expressed in around 70% of mainly small- and medium-sized neurons. Many colocalize with calcitonin gene-related peptide and isolectin B4, and thus represent nociceptors. NECAB1/2 neurons are much more abundant in DRGs than the Ca2+-binding proteins (parvalbumin, calbindin, calretinin, and secretagogin) studied to date. In the spinal cord, the NECAB1/2 distribution is mainly complementary. NECAB1 labels interneurons and a plexus of processes in superficial layers of the dorsal horn, commissural neurons in the intermediate area, and motor neurons in the ventral horn. Using CLARITY, a novel, bilaterally connected neuronal system with dendrites that embrace the dorsal columns like palisades is observed. NECAB2 is present in cell bodies and presynaptic boutons across the spinal cord. In the dorsal horn, most NECAB1/2 neurons are glutamatergic. Both NECAB1/2 are transported into dorsal roots and peripheral nerves. Peripheral nerve injury reduces NECAB2, but not NECAB1, expression in DRG neurons. Our study identifies NECAB1/2 as abundant Ca2+-binding proteins in pain-related DRG neurons and a variety of spinal systems, providing molecular markers for known and unknown neuron populations of mechanosensory and pain circuits in the spinal cord.Calcium (Ca2+) plays a crucial role in many and diverse cellular processes, including neurotransmission (1). Glutamate and neuropeptides are neurotransmitters released from the central terminals of dorsal root ganglion (DRG) neurons in the spinal dorsal horn, where signals for different sensory modalities, including pain, are conveyed to higher centers (212). Neurotransmitter release is tightly regulated by Ca2+-dependent SNARE proteins whose activity is regulated by Ca2+-binding proteins (CaBPs) (1, 7, 13).Parvalbumin (PV), calbindin D-28K (CB), calretinin (CR), and secretagogin (Scgn) are extensively studied EF-hand CaBPs, and they have also emerged as valuable anatomical markers for morphologically and functionally distinct neuronal subpopulations (1417). The expression of CaBPs in DRG neurons has been thoroughly studied (18). Moreover, neuronal Ca2+ sensor 1 and downstream regulatory element-antagonist modulator (DREAM) are also EF-hand Ca2+-binding proteins in DRGs and the spinal cord (19, 20). Despite these advances, a CaBP has so far not been characterized in the majority of small- and medium-sized DRG neurons, many of which represent nociceptors.The subfamily of neuronal Ca2+-binding proteins (NECABs) consists of three members (NECAB1–NECAB3), probably as a result of gene duplication (21). NECABs are also EF-hand proteins, with one pair of EF-hand motifs in the N terminus and a putative antibiotic biosynthesis monooxygenase domain in the C terminus, which are linked by a NECAB homogeneous region (22). NECAB1/2 are restricted to the nervous system, whereas NECAB3 is also expressed in the heart and skeletal muscle (21).NECAB1 was first identified as the target protein of synaptotagmin I C2A-domain by affinity chromatography, with its expression restricted to layer 4 cortical pyramidal neurons, inhibitory interneurons, and hippocampal CA2 pyramidal cells in mouse brain (21, 23). The gene of the second member was cloned from mouse and initially named Necab. It encodes a 389-aa (NECAB2) (24). NECAB2 was identified as a downstream target of Pax6 in mouse retina, which is involved in retinal development (24, 25), as well as being a binding partner for the adenosine A2A receptor (22). Furthermore, an interaction between NECAB2 and metabotropic glutamate receptor 5 (mGluR5) was demonstrated in rat hippocampal pyramidal cells, possibly regulating mGluR5’s coupling to its signaling machinery (26). Finally, NECAB3, also known as XB51, was isolated as an interacting target for the neuron-specific X11-like protein and is possibly involved in the pathogenesis of Alzheimer’s disease (27, 28).Very recently, NECAB1/2 were shown to have complementary expression patterns in mouse hippocampus at the mRNA and protein levels, whereas NECAB3 is broadly distributed in the hippocampus (29). NECAB1-expressing cells were seen throughout the cell-sparse layers of Ammon’s horn and the hilus of the dentate gyrus. In contrast, NECAB2 is enriched in pyramidal cells of the CA2 region. A minority of NECAB1+ neurons were GABAergic yet did not coexpress PV, CB, or CR (29).Here, we investigated the expression of NECAB1/2 in mouse DRGs and spinal cord using quantitative PCR (qPCR), immunohistochemistry (also combined with CLARITY) (30), and Western blotting. We compared the distribution of NECABs with that of the four CaBPs restricted to neurons, PV, CB, CR, or Scgn. NECAB+ neurons in the spinal dorsal horn were phenotyped using transgenic mice harboring genetic markers for excitatory [vesicular glutamate transporter 2 (VGLUT2)] (31) or inhibitory [glutamate decarboxylase 67 (GAD67)] (32) cell identities. Finally, the effect of peripheral nerve injury was analyzed.  相似文献   
19.
ObjectivePreclinical and genetic epidemiologic studies suggest that modulating cytochrome P450 (CYP)-mediated arachidonic acid metabolism may have therapeutic utility in the management of coronary artery disease (CAD). However, predictors of inter-individual variation in CYP-derived eicosanoid metabolites in CAD patients have not been evaluated to date. Therefore, the primary objective was to identify clinical factors that influence CYP epoxygenase, soluble epoxide hydrolase (sEH), and CYP ω-hydroxylase metabolism in patients with established CAD.MethodsPlasma levels of epoxyeicosatrienoic acids (EETs), dihydroxyeicosatrienoic acids (DHETs), and 20-hydroxyeicosatetraenoic acid (20-HETE) were quantified by HPLC–MS/MS in a population of patients with stable, angiographically confirmed CAD (N = 82) and healthy volunteers from the local community (N = 36). Predictors of CYP epoxygenase, sEH, and CYP ω-hydroxylase metabolic function were evaluated by regression.ResultsObesity was significantly associated with low plasma EET levels and 14,15-EET:14,15-DHET ratios. Age, diabetes, and cigarette smoking also were significantly associated with CYP epoxygenase and sEH metabolic activity, while only renin-angiotensin system inhibitor use was associated with CYP ω-hydroxylase metabolic activity. Compared to healthy volunteers, both obese and non-obese CAD patients had significantly higher plasma EETs (P < 0.01) and epoxide:diol ratios (P < 0.01), whereas no difference in 20-HETE levels was observed (P = NS).ConclusionsCollectively, these findings suggest that CYP-mediated eicosanoid metabolism is dysregulated in certain subsets of CAD patients, and demonstrate that biomarkers of CYP epoxygenase and sEH, but not CYP ω-hydroxylase, metabolism are altered in stable CAD patients relative to healthy individuals. Future studies are necessary to determine the therapeutic utility of modulating these pathways in patients with CAD.  相似文献   
20.

Purpose

Our objectives were primarily to review the published literature on complications in neuromuscular scoliosis (NMS) surgery and secondarily, by means of a meta-analysis, to determine the overall pooled rates (PR) of various complications associated with NMS surgery.

Methods

PubMed and Embase databases were searched for studies reporting the outcomes and complications of NMS surgery, published from 1997 to May 2011. We focused on NMS as defined by the Scoliosis Research Society’s classification. We measured the pooled estimate of the overall complication rates (PR) using a random effects meta-analytic model. This model considers both intra- and inter-study variation in calculating PR.

Results

Systematic review and meta-analysis were performed for 68 cohort and case–control studies with a total of 15,218 NMS patients. Pulmonary complications were the most reported (PR = 22.71 %) followed by implant complications (PR = 12.51 %), infections (PR = 10.91 %), neurological complications (PR = 3.01 %) and pseudoarthrosis (PR = 1.88 %). Revision, removal and extension of implant had highest PR (7.87 %) followed by malplacement of the pedicle screws (4.81 %). Rates of individual studies have moderate to high variability. The studies were heterogeneous in methodology and outcome types, which are plausible explanations for the variability; sensitivity analysis with respect to age at surgery, sample size, publication year and diagnosis could also partly explain this variability. In regard to surgical complications affiliated with various surgical techniques in NMS, the level of evidence of published literature ranges between 2+ to 2−; the subsequent recommendations are level C.

Conclusion

NMS patients have diverse and high complication rates after scoliosis surgery. High PRs of complications warrant more attention from the surgical community. Although the PR of all complications are affected by heterogeneity, they nevertheless provide valuable insights into the impact of methodological settings (sample size), patient characteristics (age at surgery), and continual advances in patient care on complication rates.

Electronic supplementary material

The online version of this article (doi:10.1007/s00586-012-2542-2) contains supplementary material, which is available to authorized users.  相似文献   
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