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Background and aimsWe intended to investigate the predictors for bowel resection in infants with necrotizing enterocolitis (NEC). We further developed a scoring system for better predicting bowel resection.MethodsA total of 207 infants who underwent surgical management at Children's Hospital, Chongqing Medical University between April 2008 and December 2020 were identified for the following investigation. Bowel resection was reviewed among the infants who underwent the procedure. Potential parameters related to bowel resection were explored using a multiple logistic regression method, and then a scoring system was developed.ResultsAmong the 207 patients who underwent operative intervention that were reviewed, 109 infants underwent bowel resection. Multivariate logistic regression analysis showed that birth weight, hypotension, neutropenia, pneumoperitoneum, acidosis, and intestinal wall thickness were predictors related to the occurrence of bowel resection. A 6-point scoring system was further developed based on the obtained total coefficient, and the infants could be divided into low-, moderate- and high-risk groups according to cut values of 7 and 13.ConclusionThe results of this study demonstrated that severe NEC features and low birth weight were associated with bowel resection. The risk scoring system could accurately separate infants that were suspected to have bowel loss during surgery.  相似文献   
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Although methadone is effective in the management of acute pain, the complexity of its absorption-distribution-metabolism-excretion profile limits its use as an opioid of choice for perioperative analgesia. Because deuteration is known to improve the pharmacokinetic, pharmacodynamic and toxicological properties of some drugs, here we characterized the single dose pharmacokinetic properties and post-operative analgesic efficacy of d9-methadone.The pharmacokinetic profiles of d9-methadone and methadone administered intravenously to CD-1 male mice revealed that deuteration leads to a 5.7- and 4.4-fold increase in the area under the time-concentration curve and maximum concentration in plasma, respectively, as well as reduction in clearance (0.9 ± 0.3 L/h/kg vs 4.7 ± 0.8 L/h/kg). The lower brain-to-plasma ratio of d9-methadone compared to that of methadone (0.35 ± 0.12 vs 2.05 ± 0.62) suggested that deuteration decreases the transfer of the drug across the blood-brain barrier. The estimated LD50 value for a single intravenous dose of d9-methadone was 2.1-fold higher than that for methadone. Moreover, d9-methadone outperformed methadone in the efficacy against postoperative pain by primarily activating peripheral opioid receptors. Collectively, these data suggest that the replacement of three hydrogen atoms in three methyl groups of methadone altered its pharmacokinetic properties, improved safety, and enhanced its analgesic efficacy.  相似文献   
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【摘要】 报道临床症状不典型的家族性黑棘皮病1家系。先证者女,4岁,自1周岁时,颈部、腹部出现黑色斑片,近年来逐渐扩大至唇周、躯干前部。腹部皮肤全反式共聚焦显微镜检查可见乳头环下延扭曲及沟壑结构,乳头环内可见中高折光颗粒结构。先证者父亲及祖母既往有类似病史,但随着年龄增长色素沉着自发性消退,仅有局部皮纹增粗。采集先证者及父母、祖母外周血,对先证者外周血DNA行Panel靶向测序,结果显示,先证者存在FGFR3基因14号外显子c.1949A>C(p.Lys650Thr)错义突变,Sanger测序验证证实先证者及其父亲和祖母均存在此突变。诊断:家族性黑棘皮病。  相似文献   
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BackgroundDyslipidemia in rheumatoid arthritis (RA) patients is frequently observed, and treatment with anti-rheumatic drugs has an impact on lipid profiles. Pathophysiologically, inflammation leads to decreased blood lipids and lipoproteins; RA treatment reduces inflammation and therefore may increase lipids and lipoproteins. Whether the lipid changes with RA treatment confer an increased risk of cardiovascular disease or just reflect their potentially atheroprotective anti-inflammatory effect is currently unclear due to limited and conflicting data.ObjectiveThe aim of this review is to summarize the current knowledge on the effects of synthetic and biological disease modifying antirheumatic drugs for the treatment of RA on lipid and lipoprotein parameters.ResultsRecent studies on methotrexate emphasize its anti-atherogenic effect. Golimumab combined with methotrexate revealed a trend towards an anti-atherogenic potential. The known pro-atherogenic lipid-spectrum alterations caused by tofacitinib can be effectively treated with atorvastatin. Tocilizumab signals a favorable impact on the extent of lipid modifications when combined with methotrexate. Abatacept indicated a trend towards an anti-atherogenic lipid profile demonstrated by favorable effects on HDL-C and on the TC/HDL-C ratio. Rituximab has beneficial effects on HDL-C and ApoA1, as well as on the ApoB/ApoA1 ratio.Clinical implicationsAnti-rheumatic drugs have various effects on lipid parameters, which in part appear pro-atherogenic. However, because many of these lipid changes may well reflect their potentially atheroprotective anti-inflammatory action the cardiovascular impact of these changes remains unclear. Whatsoever, cardiovascular safety trials for antirheumatic drugs would be valuable.  相似文献   
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The activation of hepatic stellate cells (HSCs) plays a critical role in the development of liver fibrosis. The induction of apoptosis in activated HSCs during the recovery phase of hepatic fibrosis represents a potential anti-fibrotic therapy. We have previously shown that Smad2 protects against hepatic fibrogenesis; however, the role of Smad2 in the regulation of activated HSC apoptosis remains unknown. We hypothesized that Smad2 regulates the apoptosis of activated HSCs, leading to the resolution of liver fibrosis. To test this hypothesis, the livers of rats were harvested at 0 and 4 weeks after hepatic fibrosis was established by CCl4 injection. Furthermore, TGF-β1-activated HSCs were treated with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) following the silencing or overexpression of Smad2. Both the phosphorylation of Smad2 and TRAIL were detected in fibrotic liver tissues. The results of TUNEL and α-SMA double-staining showed an increase in the apoptosis of activated HSCs during the spontaneous recovery phase. The knockdown of Smad2 reduced TRAIL-induced apoptosis in TGF-β1-activated human LX-2 cells and resulted in an increased expression of α-SMA and collagen I (Col. I). In contrast, the overexpression of Smad2 increased TRAIL-induced HSC apoptosis and reduced the expression of α-SMA and Col. I. The mechanisms underlying these findings were associated with the Smad2-mediated down-regulation of X-linked inhibitor of apoptosis protein (XIAP), resulting in enhanced caspase-3 activity and apoptosis. In conclusion, Smad2 enhances TRAIL-induced apoptosis in activated HSCs, which facilitates the resolution of hepatic fibrosis.  相似文献   
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Podophyllotoxin (PPT) exhibited significant activity against P-glycoprotein mediated multidrug resistant (MDR) tumor cell lines; however, due to its poor solubility and high toxicity, PPT cannot be dosed systemically, preventing its clinical use for MDR cancer. We developed a nanoparticle dosage form of PPT by covalently conjugating PPT and polyethylene glycol (PEG) with acetylated carboxymethyl cellulose (CMC-Ac) using one-pot esterification chemistry. The polymer conjugates self-assembled into nanoparticles (NPs) of variable sizes (20–120 nm) depending on the PPT-to-PEG molar ratio (2–20). The conjugate with a low PPT/PEG molar ratio of 2 yielded NPs with a mean diameter of 20 nm and released PPT at ∼5%/day in serum, while conjugates with increased PPT/PEG ratios (5 and 20) produced bigger particles (30 nm and 120 nm respectively) that displayed slower drug release (∼2.5%/day and ∼1%/day respectively). The 20 nm particles exhibited 2- to 5-fold enhanced cell killing potency and 5- to 20-fold increased tumor delivery compared to the larger NPs. The biodistribution of the 20 nm PPT-NPs was highly selective to the tumor with 8-fold higher accumulation than all other examined tissues, while the larger PPT-NPs (30 and 120 nm) exhibited increased liver uptake. Within the tumor, >90% of the 20 nm PPT-NPs penetrated to the hypovascular core, while the larger particles were largely restricted in the hypervascular periphery. The 20 nm PPT-NPs displayed significantly improved efficacy against MDR tumors in mice compared to the larger PPT-NPs, native PPT and the standard taxane chemotherapies, with minimal toxicity.  相似文献   
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