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1.
A hyperechoic mass in the right upper quadrant of the abdomen was demonstrated in a fetus by antenatal ultrasonography (US) at 20 and 33 weeks' gestation. Postnatal US, myelography and computed tomography were performed preoperatively; the findings were judged consistent with neuroblastoma. Surgical excision and pathological examination revealed bronchopulmonary sequestration.  相似文献   
2.
Lymphoid homeostasis is required to ensure immune responsiveness and to prevent immunodeficiency. As such, the immune system must maintain distinct populations of na?ve T cells that are able to respond to new antigens as well as memory T cells specific to those antigens it has already encountered. Though both na?ve and memory T cells reside in and traffic through secondary lymphoid organs, there is growing evidence that the two populations may be regulated differently. We show here that na?ve T cell survival and memory T cell survival have different requirements for cytokines (including the interleukins IL-2, IL-4, IL-7, IL-9 and IL-15) that use the common cytokine receptor gamma chain (gamma c). Using monoclonal populations of antigen-specific CD4+ T cells, we found that na?ve T cells cannot survive without gamma c, whereas memory T cells show no such requirement. In contrast, neither na?ve nor gamma c-deficient memory T cells were impaired in their ability to proliferate and produce cytokines in response to in vivo antigenic stimulation. These data call into question the physiological role of gamma c-dependent cytokines as T cell growth factors and show that na?ve and memory CD4+ T cell survival is maintained by distinct mechanisms.  相似文献   
3.
Vertebral fractures are clinically important sequelae of a wide array of pediatric diseases. In this study, we examined the accuracy of case-finding strategies for detecting incident vertebral fractures (IVF) over 2 years in glucocorticoid-treated children (n = 343) with leukemia, rheumatic disorders, or nephrotic syndrome. Two clinical situations were addressed: the prevalent vertebral fracture (PVF) scenario (when baseline PVF status was known), which assessed the utility of PVF and low lumbar spine bone mineral density (LS BMD; Z-score <−1.4), and the non-PVF scenario (when PVF status was unknown), which evaluated low LS BMD and back pain. LS BMD was measured by dual-energy X-ray absorptiometry, vertebral fractures were quantified on spine radiographs using the modified Genant semiquantitative method, and back pain was assessed by patient report. Forty-four patients (12.8%) had IVF. In the PVF scenario, both low LS BMD and PVF were significant predictors of IVF. Using PVF to determine which patients should have radiographs, 11% would undergo radiography (95% confidence interval [CI] 8–15) with 46% of IVF (95% CI 30–61) detected. Sensitivity would be higher with a strategy of PVF or low LS BMD at baseline (73%; 95% CI 57–85) but would require radiographs in 37% of children (95% CI 32–42). In the non-PVF scenario, the strategy of low LS BMD and back pain produced the highest specificity of any non-PVF model at 87% (95% CI 83–91), the greatest overall accuracy at 82% (95% CI 78–86), and the lowest radiography rate at 17% (95% CI 14–22). Low LS BMD or back pain in the non-PVF scenario produced the highest sensitivity at 82% (95% CI 67–92), but required radiographs in 65% (95% CI 60–70). These results provide guidance for targeting spine radiography in children at risk for IVF. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Hsu  E.  Keene  D.  Ventureyra  E.  Matzinger  M.A.  Jimenez  C.  Wang  H.S.  Grimard  L. 《Journal of neuro-oncology》1998,37(3):285-293
With the increasing survival time of many pediatric patients with malignancies, unexpected symptoms or signs require diligent search for rare complications or second cancers related to the disease or treatment. We recently encountered a patient with extensive glioblastoma multiforme who developed pancytopenia six months after completion of treatment with craniospinal radiation and chemotherapy with etoposide and cyclophosphamide. Bone marrow aspirate and biopsy confirmed bone marrow metastasis from the brain tumor. He showed good partial remission with chemotherapy with carmustine and cis-platinum as demonstrated by serial bone marrow aspirate for cytology and cytogenetics and enjoyed good quality of life for eight months. 14 other patients with astrocytic glioma, two of whom are children, are reported in the literature to have diffuse bone marrow metastasis. Therefore, in patients with malignant astrocytic tumor, bone marrow metastasis, though not common, should be considered when bone pain or cytopenias occur, especially when prolonged.  相似文献   
6.

Summary

Incident vertebral fractures and lumbar spine bone mineral density (BMD) were assessed in the 12 months following glucocorticoid initiation in 65 children with nephrotic syndrome. The incidence of vertebral fractures was low at 12 months (6 %) and most patients demonstrated recovery in BMD Z-scores by this time point.

Introduction

Vertebral fracture (VF) incidence following glucocorticoid (GC) initiation has not been previously reported in pediatric nephrotic syndrome.

Methods

VF was assessed on radiographs (Genant method); lumbar spine bone mineral density (LS BMD) was evaluated by dual-energy X-ray absorptiometry.

Results

Sixty-five children were followed to 12 months post-GC initiation (median age, 5.4 years; range, 2.3–17.9). Three of 54 children with radiographs (6 %; 95 % confidence interval (CI), 2–15 %) had incident VF at 1 year. The mean LS BMD Z-score was below the healthy average at baseline (mean ± standard deviation (SD), ?0.5?±?1.1; p?=?0.001) and at 3 months (?0.6?±?1.1; p?<?0.001), but not at 6 months (?0.3?±?1.3; p?=?0.066) or 12 months (?0.3?±?1.2; p?=?0.066). Mixed effect modeling showed a significant increase in LS BMD Z-scores between 3 and 12 months (0.22 SD; 95 % CI, 0.08 to 0.36; p?=?0.003). A subgroup (N?=?16; 25 %) had LS BMD Z-scores that were ≤?1.0 at 12 months. In these children, each additional 1,000 mg/m2 of GC received in the first 3 months was associated with a decrease in LS BMD Z-score by 0.39 at 12 months (95 % CI, ?0.71 to ?0.07; p?=?0.017).

Conclusions

The incidence of VF at 1 year was low and LS BMD Z-scores improved by 12 months in the majority. Twenty-five percent of children had LS BMD Z-scores ≤?1.0 at 12 months. In these children, LS BMD Z-scores were inversely associated with early GC exposure, despite similar GC exposure compared to the rest of the cohort.  相似文献   
7.

Background

The Genant semiquantitative (GSQ) method has been a standard procedure for diagnosis of vertebral fractures in adults but has only recently been shown to be of clinical utility in children. Observer agreement using the GSQ method in this age group has not been described.

Objective

To evaluate observer agreement on vertebral readability and vertebral fracture diagnosis using the GSQ method in pediatric vertebral morphometry.

Materials and methods

Spine radiographs of 186 children with acute lymphoblastic leukemia were evaluated independently by three radiologists using the same GSQ methodology as in adults. A subset of 100 radiographs was evaluated on two occasions.

Results

An average of 4.7% of vertebrae were unreadable for the three radiologists. Intraobserver Cohen’s kappa (κ) on readability ranged from 0.434 to 0.648 at the vertebral level and from 0.416 to 0.611 at the patient level, while interobserver κ for readability had a range of 0.330 to 0.504 at the vertebral level and 0.295 to 0.467 at the patient level. Intraobserver κ for the presence of vertebral fracture had a range of 0.529 to 0.726 at the vertebral level and was 0.528 to 0.767 at the patient level. Interobserver κ for fracture at the vertebral level ranged from 0.455 to 0.548 and from 0.433 to 0.486 at the patient level.

Conclusion

Most κ values for both intra- and interobserver agreement in applying the GSQ method to pediatric spine radiographs were in the moderate to substantial range, comparable to the performance of the technique in adult studies. The GSQ method should be considered for use in pediatric research and clinical practice.  相似文献   
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9.
Raising plasma free fatty acid (FFA) levels reduces muscle glucose uptake, but the effect of FFAs on splanchnic glucose uptake, total glucose output, and glucose cycling may also be critical to producing lipid-induced glucose intolerance. In eight normal volunteers, we measured glucose turnover and cycling rates ([2H7]glucose infusion) during a moderately hyperglycemic (7.7 mmol/l) hyperinsulinemic clamp, before and after ingestion of a labeled (dideuterated) oral glucose load (700 mg/kg). Each test was performed twice, with either a lipid or a saline infusion; four subjects also had a third test with a glycerol infusion. As shown by similar rates of exogenous glucose appearance, the lipid infusion did not reduce first-pass splanchnic glucose uptake (saline 1.48+/-0.18, lipid 1.69+/-0.17, and glycerol 1.88+/-0.17 mmol/kg per 180 min; NS), but it reduced peripheral glucose uptake by 40% (P < 0.01 vs. both saline and glycerol infusions). Before oral ingestion of glucose, total glucose output was similarly increased by the lipid and glycerol infusions. Total glucose output was significantly increased by FFAs after oral ingestion of glucose (saline 3.68+/-1.15, glycerol 3.68+/-1.70, and lipid 7.92+/-0.88 micromol x kg(-1) x min(-1); P < 0.01 vs. saline and P < 0.05 vs. glycerol). The glucose cycling rate was approximately 2.7 micromol x kg(-1) x min(-1) with the three infusions and tended to decrease all along the lipid infusion, which argues against a stimulation of glucose-6-phosphatase by FFAs. It is concluded that in situations of moderate hyperinsulinemia-hyperglycemia, FFAs reduce peripheral but not splanchnic glucose uptake. Total glucose output is increased by FFAs, by a mechanism that does not seem to involve stimulation of glucose-6-phosphatase.  相似文献   
10.
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