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991.
Sweet's syndrome, or febrile neutrophilic dermatosis, is a process characterized by fever, red tender plaques, neutrophilia and neutrophilic dermal infiltrate with papilar edema in the absence of vasculitis. The association with intestinal inflammatory disease is inusual, a new case associated with ulcerative colitis is reported, and we perform a literature review of Sweet's associated intestinal inflammatory disease.  相似文献   
992.
993.
Introduction and objectivesWe assessed the long-term hemodynamic performance of transcatheter heart valve (THV) by paired transthoracic echocardiography (TTE), and the incidence, characteristics and factors associated with THV structural valve degeneration (SVD).MethodsA total of 212 patients who underwent transcatheter aortic valve replacement and had a potential follow-up > 5 years with at least 1 TTE ≥ 1-year postprocedure were included. All patients had a TTE at 1 to 5 years and 36 had another one at 6 to 10 years. SVD was defined as subclinical (increase > 10 mmHg in mean transvalvular gradient +  decrease > 0.3 cm2 in valve area and/or new-onset mild or moderate aortic regurgitation) and clinically relevant (increase > 20 mmHg in mean transvalvular gradient + decrease > 0.6 cm2 in valve area and/or new-onset moderate-to-severe aortic regurgitation). Fifteen patients had a transesophageal echocardiography at the time of SVD diagnosis, and 85 an opportunistic computed tomography examination at 1 (0.5-2) years.ResultsTransvalvular mean gradient increased and valve area decreased over time (P < .01). At 8 years of follow-up, SVD occurred in 30.2% of patients (clinically relevant: 9.3%). Transesophageal echocardiography revealed thickened and reduced-mobility leaflets in 80% and 73% of SVD cases, respectively. No baseline or procedural factors were associated with SVD. THV underexpansion (3.5%) or eccentricity (8.2%) had no impact on valve hemodynamics/SVD at follow-up.ConclusionsA gradual THV hemodynamic deterioration occurred throughout a 10-year period, leading to SVD in ~30% of patients (clinically relevant in < 10%). Leaflet morphology/mobility were frequently impaired in SVD cases, but THV geometry did not influence valve hemodynamics or SVD.  相似文献   
994.
Venous thromboembolism (VTE) is a common and serious complication in patients with cancer; treatment guidelines recommend extended therapy of ≥6 months with low-molecular-weight heparin (LMWH) for treatment and prevention of recurrent VTE (rVTE) in this population. This post hoc analysis used data from the CLOT study—a phase III, randomized, open-label, controlled study (N = 676)—to compare the efficacy and safety of dalteparin, a LMWH, versus vitamin K antagonist (VKA) for prevention of rVTE in patients with cancer and renal impairment (creatinine clearance <60 ml/min). Overall, 162/676 (24 %) patients had renal impairment at baseline. Patients received subcutaneous dalteparin 200 IU/kg once daily during month 1, followed by 150 IU/kg once daily for months 2–6; or VKA once daily for 6 months, with initial overlapping subcutaneous dalteparin 200 IU/kg once daily for ≥5 days until international normalized ratio was 2.0–3.0 for 2 consecutive days. Endpoints included the rates of rVTE (primary) and bleeding events. Overall, fewer dalteparin-treated patients (2/74 [2.7 %]) experienced ≥1 adjudicated symptomatic rVTE compared with VKA-treated patients (15/88 [17.0 %]; hazard ratio = 0.15 [95 % confidence interval 0.03–0.65]; p = 0.01). Bleeding event rates for both treatments were similar (p = 0.47). In summary, compared with VKA, dalteparin significantly reduced risk of rVTE in patients with cancer and renal impairment (p = 0.01) while exhibiting a comparable safety profile. This analysis supports dosing patients with renal impairment in accordance with patients with normal renal function; however, anti-Xa monitoring could be considered to further support safety in selected patients, particularly those with very severe renal impairment.  相似文献   
995.
996.
Under conditions of sustained hyperglycemia, glycogen accumulates in pancreatic islets, but not so in acinar pancreatic cells. We investigated whether advantage could be taken of such a situation in the perspective of the noninvasive imaging of the endocrine pancreas. Control rats or animals injected with streptozotocin (STZ) were infused with solutions of d-glucose mixed with a tracer amount of d-[U-14C]glucose, and the radio-active glycogen content of both liver and pancreas was then measured. After 48 h of infusion, the radio-active glycogen content of the pancreas was 30 times lower in STZ rats than in control animals, coinciding with a 50 times lower insulin content. In the control rats, a sizable labeling of pancreatic glycogen was also recorded when d-[U-14C]glucose was infused for only the last 4 h of unlabeled d-glucose infusion; such a labeling was not decreased when the animals were further infused for 1 h with only the unlabeled hexose. Moreover, a pronounced difference in the pancreatic gland and blood radioactive content of control rats was still observed when the hyperglycemic animals were killed only 40 min after the iv injection of d-[U-14C]glucose. In STZ rats transplanted with islets and later infused with d-[U-14C]glucose, the total radioactive content and radioactive glycogen content were both much higher in the transplanted islets than in the pancreatic gland. These results allow one to define the conditions under which the administration of either 2-deoxy-2-[18F]fluoro-d-glucose or 11C-labeled d-glucose could conceivably be used to favor the selective labeling of the endocrine, as distinct from exocrine, pancreas.  相似文献   
997.
The authors report 2 cases of thrombolytic therapy by Urokinase at the dose of 4 500 U/kg/hour, for 24 hours, in patients with thrombosis of a Bjork aortic and Lillehei mitral valve prostheses, and assess the efficacy with a review of the world literature. The first case was a 65 year old woman who received a Bjork No 25 aortic valve prosthesis for aortic regurgitation. Two years later oral anti-vitamin K anticoagulants were replaced by an association of Aspirin-Persantine. She developed acute pulmonary oedema secondary to thrombosis of her valve during the fifth postoperative year. Treatment with Urokinase was successful (4 500 U/kg/hour for 24 hours). The second cases was a 33 year old woman who received a Lillehei No 27 mitral valve prosthesis for mitral regurgitation due to infective endocarditis. Six years later, during a period of apparently ineffective oral anticoagulation, she developed subacute pulmonary oedema due to thrombosis of her prosthesis. Urokinase therapy was successful after 4 hours, but the valve surface area on cardiac catheterisation was decreased and elective reoperation to change the prosthesis was decided upon. Prosthetic valve thrombosis is a serious complication with an operative mortality of 68.6% (35 deaths out of 51 reoperations in the worl literature) whilst the efficacy of thrombolytic therapy would appear to be about 80%. When thrombosis is progressive, the valve has to be changed surgically, but when it is secondary, thrombolytic therapy at least helps the patient survive the acute phase.  相似文献   
998.
European Archives of Oto-Rhino-Laryngology - In the field of radiotherapy, there is very little scientific data on the management of nonagenarians, especially in patients aged 90&nbsp;years or...  相似文献   
999.
Myeloproliferative neoplasms (MPNs) are characterized by the clonal expansion of one or more myeloid cell lineage. In most cases, proliferation of the malignant clone is ascribed to defined genetic alterations. MPNs are also associated with aberrant expression and activity of multiple cytokines; however, the mechanisms by which these cytokines contribute to disease pathogenesis are poorly understood. Here, we reveal a non-redundant role for steady-state IL-33 in supporting dysregulated myelopoiesis in a murine model of MPN. Genetic ablation of the IL-33 signaling pathway was sufficient and necessary to restore normal hematopoiesis and abrogate MPN-like disease in animals lacking the inositol phosphatase SHIP. Stromal cell–derived IL-33 stimulated the secretion of cytokines and growth factors by myeloid and non-hematopoietic cells of the BM, resulting in myeloproliferation in SHIP-deficient animals. Additionally, in the transgenic JAK2V617F model, the onset of MPN was delayed in animals lacking IL-33 in radio-resistant cells. In human BM, we detected increased numbers of IL-33–expressing cells, specifically in biopsies from MPN patients. Exogenous IL-33 promoted cytokine production and colony formation by primary CD34+ MPN stem/progenitor cells from patients. Moreover, IL-33 improved the survival of JAK2V617F-positive cell lines. Together, these data indicate a central role for IL-33 signaling in the pathogenesis of MPNs.  相似文献   
1000.
Combinations of β-lactams with clavulanate are currently being investigated for tuberculosis treatment. Since Mycobacterium tuberculosis produces a broad spectrum β-lactamase, BlaC, the success of this approach could be compromised by the emergence of clavulanate-resistant variants, as observed for inhibitor-resistant TEM variants in enterobacteria. Previous analyses based on site-directed mutagenesis of BlaC have led to the conclusion that this risk was limited. Here, we used a different approach based on determination of the crystal structure of β-lactamase BlaMAb of Mycobacterium abscessus, which efficiently hydrolyzes clavulanate. Comparison of BlaMAb and BlaC allowed for structure-assisted site-directed mutagenesis of BlaC and identification of the G132N substitution that was sufficient to switch the interaction of BlaC with clavulanate from irreversible inactivation to efficient hydrolysis. The substitution, which restored the canonical SDN motif (SDG→SDN), allowed for efficient hydrolysis of clavulanate, with a more than 104-fold increase in kcat (0.41 s−1), without affecting the hydrolysis of other β-lactams. Mass spectrometry revealed that acylation of BlaC and of its G132N variant by clavulanate follows similar paths, involving sequential formation of two acylenzymes. Decarboxylation of the first acylenzyme results in a stable secondary acylenzyme in BlaC, whereas hydrolysis occurs in the G132N variant. The SDN/SDG polymorphism defines two mycobacterial lineages comprising rapidly and slowly growing species, respectively. Together, these results suggest that the efficacy of β-lactam–clavulanate combinations may be limited by the emergence of resistance. β-Lactams active without clavulanate, such as faropenem, should be prioritized for the development of new therapies.  相似文献   
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