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941.
ObjectiveHigh-value care guidelines from multiple medical societies recommend against imaging for the initial evaluation of low back pain in the absence of red flag symptoms. We aimed to determine the current temporal and geographic landscape of imaging ordering patterns for this indication among US primary care providers.MethodsUsing a national commercial insurance claims database, we identified patients between 18 and 64 years old who presented to a primary care provider for an initial evaluation of low back pain between 2011 and 2016. Patients were identified via International Classification of Diseases codes, and the use of diagnostic imaging was identified by Current Procedural Terminology codes. Geographic regions were based on the location of patient residence.ResultsOverall, 627,118 encounters met inclusion criteria. Imaging acquisitions increased over time, from 14% of encounters in 2011 to 16% in 2016 (P < .01). Radiographs represented 96% of ordered imaging, CT 2%, and MRI 3%. The likelihood of having any imaging for low back pain varied significantly by US census region and by US state (P < .01). The greatest use of imaging was in the Midwest (13.9%) and the South (18.5%), and lowest in the Northeast and West (6.2% and 13.6%).DiscussionImaging utilization for the initial evaluation of low back pain by primary care providers has increased on a national level from 2011 to 2016, largely represented by radiographs. Significant regional variation also exists. Encouragingly, the use of advanced imaging has remained at a low level in the primary care setting (<1.0%).  相似文献   
942.
943.
PurposeTo evaluate the safety and efficacy of oxygen-ozone treatment delivered via a novel, handheld ozone-generating device for improving pain and function in herniated disc patients.Materials and MethodsA total of 39 patients with contained herniated lumbar discs received oxygen-ozone treatment at 1 of 3 centers. Treatment consisted of injection of 2% ozone (10 mL): 3 mL delivered into the nucleus pulposus and 7 mL delivered into the adjacent paravertebral tissues. The first 8 patients received only ozone injections, whereas subsequent patients also received periganglionic methylprednisolone (40 mg) and 0.5% bupivacaine (1 mL) injections. Patients were evaluated at baseline and at 1 month, 6 months, and 12 months after treatment using the Oswestry Disability Index (ODI) and the Visual Analogue Scale (VAS) for leg pain and for back pain. Analgesic medication use was also assessed at each timepoint.ResultsOverall, 91% (32/35) of the per-protocol patients (those who completed follow-up and did not have significant protocol deviations) showed detectable improvement in ODI at 1-month follow-up; this increased to 93% (26/28) of patients at 12-months follow-up. At 1 month after treatment, 60% (21/35) of patients showed significant improvement in ODI scores (P = .01); 54% (19/35) showed significant improvement in VAS scores for leg pain (P = .05); and 49% (17/35) showed significant improvement in VAS scores for back pain (P = .12). At 6 months after treatment, 67% (22/33) of patients showed significant improvement in ODI scores (P = .02); 64% (21/33) showed significant improvement in VAS scores for leg pain (P = .01); and 52% (17/33) showed significant improvement in VAS scores for back pain (P = .12). At 12 months after treatment, 68% (19/28) of patients showed significant improvement in ODI scores (P < .01); 64% (18/28) showed significant improvement in VAS scores for leg pain (P < .01); and 61% (17/28) showed significant improvement in VAS scores for back pain (P = .09). Leg pain typically subsided more quickly than back pain. Use of analgesic medications also significantly decreased at all follow-up timepoints compared to baseline (P < .01). There were no adverse events or device-related issues.ConclusionsAt 1, 6, and 12 months after treatment, patients experienced significant improvements in pain and function as well as significantly decreased use of analgesic medication. Taken together with the absence of adverse events at 1-year follow-up, these data suggest that oxygen-ozone treatment is a safe and effective therapy for contained herniated discs.  相似文献   
944.
PurposeTo label Clostridium novyi-NT spores (C. novyi-NT) with iron oxide nanoclusters and track distribution of bacteria during magnetic resonance (MR) imaging-monitored locoregional delivery to liver tumors using intratumoral injection or intra-arterial transcatheter infusion.Materials and MethodsVegetative state C. novyi-NT were labeled with iron oxide particles followed by induction of sporulation. Labeling was confirmed with fluorescence microscopy and transmission electron microscopy (TEM). T2 and T2* relaxation times for magnetic clusters and magnetic microspheres were determined using 7T and 1.5T MR imaging scanners. In vitro assays compared labeled bacteria viability and oncolytic potential to unlabeled controls. Labeled spores were either directly injected into N1-S1 rodent liver tumors (n = 24) or selectively infused via the hepatic artery in rabbits with VX2 liver tumors (n = 3). Hematoxylin-eosin, Prussian blue, and gram staining were performed. Statistical comparison methods included paired t-test and ANOVA.ResultsBoth fluorescence microscopy and TEM studies confirmed presence of iron oxide labels within the bacterial spores. Phantom studies demonstrated that the synthesized nanoclusters produce R2 relaxivities comparable to clinical agents. Labeling had no significant impact on overall growth or oncolytic properties (P >.05). Tumor signal-to-noise ratio (SNR) decreased significantly following intratumoral injection and intra-arterial infusion of labeled spores (P <.05). Prussian blue and gram staining confirmed spore delivery.ConclusionsC. novyi-NT spores can be internally labeled with iron oxide nanoparticles to visualize distribution with MR imaging during locoregional bacteriolytic therapy involving direct injection or intra-arterial transcatheter infusion.  相似文献   
945.
946.
Introduction: PPIs are involved in every disease and specific modulation of these PPIs with small molecules would significantly improve our prospects of developing therapeutic agents. Both industry and academia have engaged in the identification and use of PPI inhibitors. However in comparison, the opposite strategy of employing small-molecule stabilizers of PPIs is underrepresented in drug discovery.

Areas covered: PPI stabilization has not been exploited in a systematic manner. Rather, this concept validated by a number of therapeutically used natural products like rapamycin and paclitaxel has been shown retrospectively to be the basis of the activity of synthetic molecules originating from drug discovery projects among them lenalidomide and tafamidis. Here, the authors cover the growing number of synthetic small-molecule PPI stabilizers to advocate for a stronger consideration of this as a drug discovery approach.

Expert opinion: Both the natural products and the growing number of synthetic molecules show that PPI stabilization is a viable strategy for drug discovery. There is certainly a significant challenge to adapt compound libraries, screening techniques and downstream methodologies to identify, characterize and optimize PPI stabilizers, but the examples of molecules reviewed here in our opinion justify these efforts.  相似文献   
947.
Lethal licorice     
The human body's response to extreme stress is complex and this patient's experience illustrates just how traumatic it can be both physiologically and psychologically. While Alan's experience was extreme and unusual, it serves to emphasise the importance of diet and health maintenance particularly for the cardiac patient.  相似文献   
948.
Child Psychiatry & Human Development - Little is known about the long-term prognosis of children with pediatric acute-onset neuropsychiatric syndrome (PANS). Out of the 46 eligible patients...  相似文献   
949.
950.
Galactosyl transferase knock-out pig lungs fail rapidly in baboons. Based on previously identified lung xenograft injury mechanisms, additional expression of human complement and coagulation pathway regulatory proteins, anti-inflammatory enzymes and self-recognition receptors, and knock-down of the β4Gal xenoantigen were tested in various combinations. Transient life-supporting GalTKO.hCD46 lung function was consistently observed in association with either hEPCR (n = 15), hTBM (n = 4), or hEPCR.hTFPI (n = 11), but the loss of vascular barrier function in the xenograft and systemic inflammation in the recipient typically occurred within 24 h. Co-expression of hEPCR and hTBM (n = 11) and additionally blocking multiple pro-inflammatory innate and adaptive immune mechanisms was more consistently associated with survival >1 day, with one recipient surviving for 31 days. Combining targeted genetic modifications to the lung xenograft with selective innate and adaptive immune suppression enables prolonged initial life-supporting lung function and extends lung xenograft recipient survival, and illustrates residual barriers and candidate treatment strategies that may enable the clinical application of other organ xenografts.  相似文献   
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