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61.

Background

Acute kidney injury (AKI) carries a large burden of morbidity and mortality. Early diagnosis may lead to better strategies of clinical care. Cardiac surgery involving cardiopulmonary bypass is associated with a significant incidence of AKI. The study objective was to determine whether or not preoperative fibroblast growth factor-23 (FGF23) levels differed among pediatric patients who did or did not develop AKI following cardiac surgery.

Methods

A nested case–control study was performed. FGF23 levels were measured pre- and post-operatively in 19 children without chronic kidney disease (CKD) who underwent cardiopulmonary bypass. Five patients developed AKI and 14 patients served as controls.

Results

FGF23 levels in patients who developed AKI following cardiac surgery were elevated above normal levels, both pre-operatively and post-operatively compared with those patients who did not develop AKI. Relative risk of developing AKI when the pre-operative FGF23 level was >86 RU/mL was 2.0 (p?=?0.033). Preoperative FGF23 levels correlated with post-operative fluid gain (correlation coefficient 0.607, p?=?0.0059).

Conclusions

FGF23 may serve as a pre-operative prognostic indicator of the development of AKI following cardiopulmonary bypass surgery in pediatric patients without CKD. Identifying patients more likely to have AKI following surgery provides a means of achieving closer clinical management of AKI and fluid balance.  相似文献   
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Eribulin mesylate (E7389, INN:eribulin mesilate Halaven®) is a non-taxane microtubule dynamics inhibitor currently in clinical use for advanced breast cancer. Other microtubule-targeting agents for breast cancer, including paclitaxel and ixabepilone, display a common treatment dose-limiting toxicity of peripheral neuropathy (PN). In an earlier study, we found eribulin mesylate had a lower propensity to induce PN in mice than either paclitaxel or ixabepilone. In the current study, we compared additional PN induced by paclitaxel versus eribulin mesylate when administered to mice with preexisting paclitaxel-induced PN. Initially, paclitaxel at 0.75 × its maximum tolerated dose (MTD; 22.5 mg/kg) was given on a Q2Dx3 regimen for 2 weeks. The second chemotherapy was 0.5 MTD eribulin mesylate (0.875 mg/kg) or paclitaxel (15 mg/kg) on a similar regimen, starting 2 weeks after the first. Initial paclitaxel treatment produced significant decreases in caudal nerve conduction velocity (NCV; averaging 19.5 ± 1 and 22.2 ± 1.3 %, p < 0.001) and amplitude (averaging 53.2 ± 2.6 and 72.4 ± 2.1 %, p < 0.001) versus vehicle when measured 24 h or 2 weeks after dosing cessation, respectively. Additional 0.5 MTD paclitaxel further reduced caudal NCV and amplitude relative to immediately before initiation of the second regimen (by 11 ± 2.1 and 59.2 ± 5 %, p < 0.01, respectively). In contrast, 0.5 MTD eribulin mesylate caused no further decrease in caudal NCV. In conclusion, unlike additional paclitaxel treatment, eribulin mesylate administered to mice with preexisting paclitaxel-induced PN had limited additional deleterious effects at 6 weeks. These preclinical data suggest that eribulin mesylate may have reduced tendency to exacerbate preexisting paclitaxel-induced PN in clinical settings.  相似文献   
66.

Key points

  • Intrauterine growth restriction (IUGR) is associated with short‐ and long‐term detrimental cardiometabolic effects.
  • Mice and rats are commonly used to assess IUGR, but differences in placental and fetal developmental physiology relative to those in humans highlight the need for alternative small animal IUGR models.
  • We developed a guinea pig IUGR model by gradual occlusion of uterine arteries by ameroid constrictor implantation. In this model, reduced uterine blood flow was associated with IUGR, allowing in vivo assessment of fetal growth trajectory and umbilico‐placental vascular function in conscious animals.
  • The intervention induces placental vascular dysfunction and remodelling, as well as altered fetal abdominal growth resulting in an asymmetric IUGR and preserved brain growth.

Abstract

Intra‐uterine growth restriction (IUGR) is associated with short and long‐term metabolic and cardiovascular alterations. Mice and rats have been extensively used to study the effects of IUGR, but there are notable differences in fetal and placental physiology relative to those of humans that argue for alternative animal models. This study proposes that gradual occlusion of uterine arteries from mid‐gestation in pregnant guinea pigs produces a novel model to better assess human IUGR. Fetal biometry and in vivo placental vascular function were followed by sonography and Doppler of control pregnant guinea pigs and sows submitted to surgical placement of ameroid constrictors in both uterine arteries (IUGR) at mid‐gestation (35 days). The ameroid constrictors induced a reduction in the fetal abdominal circumference growth rate (0.205 cm day−1) compared to control (0.241 cm day−1, P < 0.001) without affecting biparietal diameter growth. Umbilical artery pulsatility and resistance indexes at 10 and 20 days after surgery were significantly higher in IUGR animals than controls (P < 0.01). These effects were associated with a decrease in the relative luminal area of placental chorionic arteries (21.3 ± 2.2% vs. 33.2 ± 2.7%, P < 0.01) in IUGR sows at near term. Uterine artery intervention reduced fetal (∼30%), placental (∼20%) and liver (∼50%) weights (P < 0.05), with an increased brain to liver ratio (P < 0.001) relative to the control group. These data demonstrate that the ameroid constrictor implantations in uterine arteries in pregnant guinea pigs lead to placental vascular dysfunction and altered fetal growth that induces asymmetric IUGR.  相似文献   
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Intranodal palisaded myofibroblastoma (IPM) usually presents as a painless, slow-growing inguinal mass. Our review of 42 cases from 13 publications indicates that two thirds of IPMs occur between the ages of 45 and 55 years, the male-female ratio is 2:1, and there is a lack of ethnic predilection. Grossly, the IPM cut surface shows areas of hemorrhage. Five microscopic features are seen: (a) compressed remnants of lymphoid tissue at the periphery; (b) spindle cells with nuclear palisading; (c) intraparenchymal hemorrhage and erythrocyte extravasation; (d) so-called amianthoid fibers; and (e) intracellular and extracellular fuchsinophilic bodies that stain positive for smooth muscle actin. Immunohistochemically, IPM is positive for smooth muscle actin and cyclin D1 and negative for S100, glial fibrillary acidic protein, CD34, and desmin, and it shows a low proliferative index of Ki-67. Electron microscopy demonstrates features of myofibroblasts and smooth muscle cells. Excellent prognosis is seen after surgical treatment, with an approximately 6% recurrence rate and no malignant transformation.  相似文献   
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The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is rapidly infecting people worldwide, resulting in the infectious disease coronavirus disease 19 (COVID‐19) that has been declared a pandemic. Much remains unknown about COVID‐19, including its effects on solid organ transplant (SOT) recipients. Given their immunosuppressed state, SOT recipients are presumed to be at high risk of complications with viral infections such as SARS‐CoV‐2. Limited case reports in single SOT recipients, however, have not suggested a particularly severe course in this population. In this report, we present a dual‐organ (heart/kidney) transplant recipient who was found to have COVID‐19 and, despite the presence of a number of risk factors for poor outcomes, had a relatively mild clinical course.  相似文献   
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