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81.
Background/PurposeCervicofacial lymphatic malformations (CFLM) are rare, potentially life-threatening vascular anomalies, yet reports on multidisciplinary treatment strategies are lacking. We evaluated outcomes for CFLMs following sclerotherapy, surgical resection, and/or medical management.MethodsWe identified children with a CFLM at a vascular anomalies center from 2004 to 2019. Exclusion criteria: retro-orbital malformations, untreated malformations, patients without follow-up. Primary clinical outcome was contour improvement, with significance defined as LM volume reduction of > 50% by cross-sectional imaging.ResultsSixty-three children met inclusion criteria: 35 with macrocystic CFLMs, six with microcystic CFLMs, and 22 with mixed-type malformations. Mean post-intervention follow-up was 27.5 months. Fifty-eight patients underwent sclerotherapy (median: two treatments). Doxycycline and/or bleomycin were used in 95% of patients. After sclerotherapy, 97% of macrocystic CFLMs improved significantly compared to 82% of mixed and 67% of microcystic lesions. Sixteen children underwent surgical resection with 75% significantly improving; two additional patients were successfully treated with sclerotherapy after debulking surgery. Six children received sirolimus for microcystic disease, of which 33% significantly improved.ConclusionSclerotherapy is very effective for macrocystic components of CFLMs, albeit less so for microcystic disease. Microcystic CFLMs frequently require surgical resection. Sirolimus is a helpful therapeutic adjunct, particularly for microcystic lesions, but more study is needed.Level of EvidenceLevel II, prognosis study  相似文献   
82.
BackgroundTransplantation of living allogeneic bone segments may permit reconstruction of large defects, particularly if viability is maintained without immunosuppression. Development of a new autogenous osseous blood supply accomplishes this goal in rodent experimental models. This study evaluates potential systemic and local inflammatory responses to this angiogenesis in a large-animal model.MethodsVascularized allogeneic tibia segments were transplanted orthotopically into matched tibial defects in Yucatan minipigs. Microvascular anastomoses of bone nutrient artery and vein were supplemented by intramedullary placement of an autogenous arteriovenous (AV) bundle in group 1. Group 2 served as a no-angiogenesis control. A 3-drug immunosuppression regimen was withdrawn after 2 weeks. During the 20-week survival period, periodic leukocyte counts and inflammatory cytokine levels were measured. Thereafter, osteocyte survival was quantified and transplant rejection graded by histologic examination and quantitative real-time polymerase chain reaction of immunologic markers.ResultsBoth groups developed an initial systemic response, which resolved after 4 to 6 weeks. No differences were seen in blood cytokine levels. Interleukin 2 expression was diminished in group 1 tibiae. As expected, nutrient pedicles had thrombosed without sustained immunosuppression, occluded by intimal hyperplasia. In group 1, angiogenesis from the autogenous AV bundle resulted in significantly less osteonecrosis (P = .04) and fibrosis (P = .02) than group 2 allotransplants.ConclusionsSystemic immune responses to large-bone allotransplants were not increased by generation of an autogenous osseous blood supply within porcine tibial bone allotransplants. Implanted AV bundles diminished inflammation and fibrosis and improved bone viability when compared to no-angiogenesis controls.  相似文献   
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PurposeWe examined the role of obesity and intraoperative red blood cell (RBC) and platelet transfusion in early allograft dysfunction (EAD) following liver transplantation (LT).MethodsThis is a retrospective analysis of 239 adult deceased-donor LT recipients over a 10-year period. EAD was defined by Olthoff’s criteria. Data collection included donor (D) and recipient (R) age, body mass index (BMI) ≥ 35 kg/m2, diabetes mellitus, allograft macrosteatosis, and intraoperative (RBC) and platelet administration. We employed logistic regression to evaluate associations of these factors with EAD. Results are presented as odds ratios (OR) and 95% confidence intervals (CI) with corresponding P values. A P ≤ .05 was considered statistically significant.ResultsEAD occurred in 85 recipients (36%). Macrosteatosis data were available for 199 donors. In the multivariate analyses, BMI-D ≥ 35 kg/m2 increased the odds of developing EAD by 156% in the entire cohort (OR 2.56, 95% CI 1.09-6.01) and by 187% in recipients with macrosteatosis data (n = 199, OR 2.87, 95% CI 1.15-7.15). Each unit of RBCs increased the odds for EAD by 8% (OR 1.08, 95% CI 1.02-1.14) and, for the subgroup of 238 recipients with macrosteatosis data, by 9% (OR 1.09, 95% CI 1.02-1.16).ConclusionWe found a significant independent association of donor obesity and intraoperative RBC transfusion with EAD but no such association for platelet administration, MELD score, age, recipient obesity, and diabetes.  相似文献   
84.
BACKGROUND CONTEXTBack and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.PURPOSETo quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.STUDY DESIGNAn immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.METHODSHuman IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.RESULTSFifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).CONCLUSIONSBMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.CLINICAL SIGNIFICANCEBMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration.  相似文献   
85.
This article describes policy processes that have led to the re-organisation of stroke care in the Czech Republic since 2011, which has been part of a broader process of care concentration in several medical fields. Currently, stroke care is provided by 13 Comprehensive and 32 Primary Stroke Centres. The paper explains factors that supported the reform implementation, reviews implications, and discusses future challenges.Mandatory reporting of quality indicators, the introduction of a benchmarking system, integration with pre-hospital emergency care, and the introduction of countrywide patient triage have supported more timely treatment for stroke patients and better quality of care. Data from the Stroke Care Quality Indicators of the Czech Stroke Society show positive trends in many areas: the number of patients treated with intravenous thrombolysis quadrupled in eight years, with 26.4 % of all acute stroke patients receiving thrombolysis in 2018. Czech Republic now ranks third in Europe in the number of thrombolysis per population and second in the number of mechanical thrombectomies per population. The Czech experience provides an example of positive outcomes of concentrated stroke care, while highlighting the importance of proper implementation processes. In particular, it is essential to involve stakeholders and to provide reputational incentives through continuous benchmarking.  相似文献   
86.
 TAG-1/axonin-1 is a neuronal cell adhesion molecule of the immunoglobulin superfamily. It is predominantly expressed during neural development and has been reported to be involved in axonal growth and pathfinding. Here, the expression of TAG-1/axonin-1 was investigated anatomically in the adult mouse brain by in situ hybridization using digoxigenin-labeled cRNA probes. Low levels of TAG-1/axonin-1 could be detected in cerebellar granule cells, in tufted and mitral cells of the olfactory bulb, and in pyramidal cells of area CA1 and CA3 of the hippocampus. We suspect that the expression of TAG-1/axonin-1 in these structures of the adult brain may serve neural plasticity. Accepted: 8 September 1997  相似文献   
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The influence of angiotensin converting enzyme (ACE) inhibition on acute extrarenal and renal potassium elimination in stable chronic renal failure has been examined in 10 male patients median age 44 y; mean CLCR 42 ml·min–1·1.73 m–2. In a double blind, placebo-controlled cross-over study, K+ 0.3 or 0.4 mmol·kg–1 body weight was infused IV on two occasions while the patients also received an infusion either of placebo or 0.5 mg of the ACE inhibitor perindoprilat in random order. Plasma K+ levels and urinary K+ excretion were measured at regular intervals. During the study patients adhered to an isocaloric diet providing a standardised daily intake of potassium and sodium (50 mmol K+ and 40 mmol Na+).The median rise in plasma K+ was not significantly different after placebo ( K 0.66 mmol·1–1) compared with to the infusion of perindoprilat ( K 0.66 mmol·1–1). The median baseline urinary K+ excretion rate was 6.5 mmol·3 h–1 before the placebo infusion and 5.9 mmol·3 h–1 before infusion of perindoprilat. During the potassium load, the urinary excretion rate rose to 16.1 mmol·3 h–1 (after placebo) and 15.1 mmol·3 h–1 after perindoprilat in the first 3 h, and it returned almost to the baseline value within the next 3 h (5.6 mmol·3 h–1 after placebo and 5.7 mmol·3 h–1 after perindoprilat); the differences were not statistically significant.With perindoprilat a decrease in mean arterial blood pressure and ACE activity, an increase in renin plasma activity and a decrease in aldosterone concentrations were observed compared to the placebo infusion. There was no significant differences plasma in adrenaline or insulin levels after either infusion.Thus, ACE inhibition did not interfere either with the extrarenal or the renal disposal of an acute potassium load in patients with chronic renal failure.  相似文献   
90.
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