Parathyroid conditions in childhood

This review of parathyroid surgery in children will briefly discuss parathyroid gland embryology and anatomy before focusing on the pathophysiology, clinical presentation, and treatment of hyperparathyroidism in children. Hyperparathyroidism (HPT) is the overproduction of PTH and it is rare in children, with an incidence of 2-5 per 100,000. This rarity means that the principles of caring for children with parathyroid disease are largely extrapolated from the richer adult experience; however, the unique pediatric aspects of parathyroid problems and their surgical treatment, including presentation, imaging, operative approach, and complications, will be considered.     

Clinical Course and Outcome of Cocaine-Induced Pneumomediastinum

Background and ObjectivesCocaine inhalation has been linked to the development of pneumomediastinum. The aim of this review was to identify the clinical course and outcome of spontaneous pneumomediastinum caused by cocaine use.Material and MethodsWe performed a literature search in English language using PubMed. We included all case reports and case series of spontaneous pneumomediastinum caused by cocaine use. Twenty-three case reports and 7 case series describing 40 patients were identified. In addition, 2 young adults who were admitted to our teaching hospital with cocaine- induced pneumomediastinum were included in this review.ResultsAmong 42 patients, 93% were presented with chest pain and 64% had subcutaneous emphysema. Symptoms subsided after a median of 24 hours, and radiological abnormalities abated after 2 to 30 days, with a median of 4.5 days. Pneumothorax was present in 19% of patients, and only 1 required chest tube placement. Patients were discharged with full recovery after 1 to 6 days, with a median of 2 days.ConclusionsCocaine-induced pneumomediastinum is a benign condition. A short observation period with outpatient follow-up is appropriate in the majority of patients. Invasive procedures have a low yield and should be based on a high degree of clinical suspicion for esophageal rupture or bronchial tree laceration.     

Genomic instability induced by ionizing radiation in human hepatocytes

The aim of this study was to characterize genomic instability induced by ionizing radiation (IR) in human hepatocytes as reflected by alterations in cloning efficiency, micronucleus (MN) frequency, and apoptosis. The human normal liver 7702 cell line (HL7702) was subjected to initial irradiation of (60)Co-γ ray at doses of 0 (control group), 2, 4, 6, 8, or 10 Gy in each group. Progeny of surviving cells from a second irradiation at dose of 2 Gy were cultured for 15 passages until they were transferred. The cloning efficiency, MN frequency, and apoptotic rate were measured after the initial irradiation, and repeated at passage 15 before and after the second irradiation. The initial irradiation resulted in a dose-dependent decline in cloning efficiency and an increase in MN frequency and apoptotic rate. At passage 15 in progeny of initially irradiated cells, cloning efficiency, MN frequency returned to control levels while apoptotic rate rose. After the second irradiation, cloning efficiency fell while a rise in MN frequency and apoptosis occurred. Our results show that the second irradiation may further enhance cell progeny injury induced by initial irradiation, such that genomic instability that may be difficult to detect after one irradiation is more apparent with subsequent irradiation.     

60Co γ射线诱发人正常肝细胞HL-7702 HAVCR2和MXR7基因表达变化研究

目的 探讨电离辐射诱导人正常肝细胞HL-7702甲型肝炎病毒受体2(HAVCR2)和MXR7基因的表达变化,为寻找辐射致肝脏损伤早期诊断标志物提供实验依据.方法 将对数生长期的人正常肝细胞HL-7702分为10组,利用中国辐射防护研究院钴-60(60Co)照射装置对各组肝细胞照射,吸收剂量率为1.29 Gy/min,吸收剂量分别为0、0.2、0.4、0.6、0.8、1.0、2.0、3.0、4.0、5.0 Gy,利用实时荧光定量聚合酶链反应(PCR)技术检测肝细胞HL-7702 HAVCR2和MXR7基因的变化,分析剂量-反应关系.结果 HAVCR2基因表达在照射后4、24 h总体上调;其中,0.2～0.8 Gy剂量组在照射后24 h基因相对表达量与照射剂量具有很好的剂量-反应关系,满足回归方程:y=0.14x2-0.48x+ 1.34;1.0～3.0Gy剂量组在照射后24 h,基因相对表达量与照射剂量呈现很好的剂量-反应关系,满足回归方程:y=0.44x+0.56.MXR7基因表达在照射后4、24 h较对照组显示出明显差异;其中,0.2～0.8 Gy剂量组MXR7基因表达在照射后4h与对照组相比总体上调,但随照射剂量增大,上调幅度降低;照射后24h,其基因表达未见明显规律;1.0～5.0 Gy剂量组MXR7基因表达在照射后24 h整体上调,且基因的表达与照射剂量呈现一定的剂量相关性,满足方程为y=0.57x+0.43.结论 电离辐射可以诱导人正常肝细胞HL-7702 HAVCR2和MXR7基因的差异表达,且基因表达与照射剂量存在一定的剂量相关性.     

Ionizing radiation induces cutaneous lipid remolding and skin adipocytes confer protection against radiation-induced skin injury

BackgroundRadiation-induced skin injury is a serious concern during radiotherapy and radiation accidents. Skin fat represents the dominant architectural component of the human skin. However, the interplay between skin fat and the progression of radiation-induced skin injury remains largely unexplored.ObjectiveThis study aims to elucidate the interplay between skin fat and the progression of radiation-induced skin injury.MethodsSD rats were irradiated with an electron beam. mRNA profiles were determined by RNA-Seq. The skin lipid mass was monitored by magnetic resonance imaging (MRI) and lipid profiles were measured by liquid chromatography-mass spectrometry (LC–MS). Human mature adipocytes isolated from dermal and subcutaneous white adipose tissues (WATs) were co-cultured with human keratinocytes (HaCaT) and skin fibroblasts (WS1) in the transwell culture system. Cell migration ability was measured by migration assay.ResultsRadiation modulated cutaneous lipid metabolism by downregulating multiple pathways. Moreover, radiation decreased skin fat mass with altered lipid metabolite profiles. The rats fed with a high-fat diet showed resistance to radiogenic skin injury compared with that with a control diet, indicating that skin lipid plays a radioprotective role. Mature adipocytes promoted the migration but not the proliferation of co-cultured skin keratinocytes and fibroblasts. Palmitic acid, the most abundant fatty acid in skin tissues, facilitated the migration of WS1 cells. Moreover, fatty acid-binding protein 4 (FABP4) could be incorporated into skin cells and promote DNA damage repair in irradiated skin fibroblasts.ConclusionRadiation induces cutaneous lipid remolding, and skin adipocytes confer a protective role against radiation-induced skin injury.     

60Co γ射线对雄性比格犬睾酮分泌及睾丸组织病理学的影响

目的：探讨⁶⁰Co γ射线急性照射对雄性比格犬睾酮分泌的影响及对睾丸的损伤。方法：检疫30 d的15只雄性比格犬,随机分为3组：空白对照组、0.5 Gy γ射线照射组和5.0 Gy γ射线照射组,照射组比格犬接受⁶⁰Co γ射线一次性全身照射,吸收剂量率为0.5 Gy/min,分别于照射后第4、7、14、28、60天采用竞争性抑制酶免疫分析法测定血清睾酮含量,照射后60 d取犬睾丸和附睾,观察脏器是否出血或坏死并进行睾丸的组织结构病理学检查。结果：γ射线照射后10~13 d,5.0 Gy γ射线照射组动物全部死亡,并出现睾丸及附睾出血;照射后60 d,0.5 Gy γ射线照射组动物体质量与空白对照组间的差异无统计学意义（P>0.05）,其睾丸平均质量为空白对照组的69%,两组间的睾丸/体质量比差异无统计学意义（P>0.05）;在照射后第4、7、14、28、60天,0.5和5.0 Gy γ射线照射组与空白对照组血清睾酮含量间的差异无统计学意义（P>0.05）;2个照射组比格犬睾丸生精细胞有不同程度坏死脱落,其中5.0 Gy γ射线照射组睾丸内无精子生成。结论：0.5和5.0 Gy ⁶⁰Co γ射线急性照射均对雄性比格犬生殖系统造成损伤,其中血清睾酮变化不明显,睾丸结构受到破坏,生精细胞及精子生成受到严重损伤。