Predator stress-induced depression is associated with inhibition of hippocampal neurogenesis in adult male mice

Stress has been suggested to disturb the 5-hydroxytryptamine system and decrease neurogenesis, which contribute to the development of depression. Few studies have investigated the effect of predator stress, a type of psychological stress, on depression and hippocampal neurogenesis in adult mice; we therefore investigated this in the present study. A total of 35 adult male Kunming mice were allocated to a cat stress group, cat odor stress group, cat stress + fluoxetine group, cat odor stress + fluoxetine group, or a control group(no stress/treatment). After 12 days of cat stress or cat odor stress, behavioral correlates of depression were measured using the open field test, elevated plus maze test, and dark-avoidance test. The concentrations of hippocampal 5-hydroxytryptamine and 5-hydroxyindoleacetic acid were measured using high-performance liquid chromatography-electrochemical detection. Neurogenesis was also analyzed using a bromodeoxyuridine and doublecortin double-immunostaining method. Cat stress and cat odor stress induced depression-like behaviors; this effect was stronger in the cat stress model. Furthermore, compared with the control group, cat stress mice exhibited lower 5-hydroxytryptamine concentrations, higher 5-hydroxyindoleacetic acid concentrations, and significantly fewer bromodeoxyuridine+/doublecortin+-labeled cells in the dentate gyrus, which was indicative of less neurogenesis. The changes observed in the cat stress group were not seen in the cat stress + fluoxetine group, which suggests that the effects of predator stress on depression and neurogenesis were reversed by fluoxetine. Taken together, our results indicate that depression-like behaviors induced by predator stress are associated with the inhibition of hippocampal neurogenesis.     

Human monocyte-derived hemangioma-like endothelial cells: evidence from an in vitro study

BACKGROUNDS: Hemangiomas are highly prevalent in newborns and infants and can lead to severe complications. However, the pathogenesis of hemangiomas is still unknown. This study was designed to examine the potential of human monocytes to differentiate into hemangioma endothelial cells. METHODS: Purified monocytes from adult human peripheral blood were cultured under a conditional culture environment supplemented with basic fibroblast growth factor and vascular endothelial growth factor. Cells cultured for 2 weeks were subjected to histological and immunochemical examinations in order to determine the expression of specific markers for hemangioma endothelial cells. RESULTS: Monocytes cultured for 2 weeks in angiogenic medium expressed human erythrocyte-type glucose transporter protein, FcgammaRII, and several other endothelial markers, all of which are deemed specific markers for hemangioma endothelial cells. However, neither CD133 nor alpha smooth muscle actin was detected in our monocyte culture. CONCLUSION: Our data suggested that monocytes are capable of differentiating into hemangioma endothelial cells under the angiogenic stimulation from microenvironment of proliferative hemangioma.     

复发性牙源性角化囊肿增长速率的临床评价

目的:评价和分析复发性牙源性角化囊肿的增长速率及其早期影像学特点。方法:选择剜除术后X线显示复发并随访6～36个月的3例下颌骨牙源性角化囊肿患者,在X线片上测量比较囊肿最大直径,计算其年均增长速率,并评估其早期影像学特征。结果:8个复发性囊肿增长速率为0.67～22.0mm/a,平均为4.79mm/a。术后短期内的复发病变生长较快,且病变一般无明显硬化缘。此外,早期发现的多个独立的小的复发病变可逐渐增长,融合成多房性囊肿。结论:复发性牙源性角化囊肿的增长速率与其复发时间密切相关,多个独立的小囊肿在迅速增大后可形成多房性病变。     

Recurrent keratocystic odontogenic tumor in the masseter muscle overlying the boney perforations: a case report

Keratocystic odontogenic tumor (KCOT) is a benign intraosseous neoplasm of odontogenic origin with high recurrence rates and tendency to invade adjacent tissue. Most recurrences occur in the first 5 years after surgery and are usually located at the site of the primary tumor in the jaws. We report a rare case of KCOT which recurred in the masseter muscle 14 years after segmental mandibulectomy and autogenous frozen lesional mandible reimplantation. The patient had undergone enucleation of KCOT in the right mandible 20 years before segmental mandibulectomy. This case could further demonstrate the aggressive behavior of KCOT.     

单克隆抗体影响利什曼原虫侵入吞噬细胞的扫描电镜观察

用扫描电镜观察在体外培养条件下利什曼原虫与小鼠腹腔吞噬细胞的相互关系。实验证明,前鞭毛体在抗杜氏利什曼单克隆抗体处理后,形态发生很大变异,部分原虫呈溶解现象,部分原虫仍可粘附于吞噬细胞外,但单克隆抗体经 56℃灭活后,则原虫形态无改变,且粘附在吞噬细胞周围,有些原虫的鞭毛及虫体前端已进入细胞内,认为其机制可能与前鞭毛体外膜上的配基与吞噬细胞受体的结合有关。     

由他汀类药物减少败血症所想到的

基于大量循证医学研究证据,他汀类药物已被视为动脉粥样硬化性心血管疾病药物治疗的基石,是惟一经大规模临床试验证实可以逆转动脉粥样硬化病变的药物。随着近年来对此类药物研究的不断深入,人们发现除调脂作用以外,他汀类药物还可能通过多种机制发挥有益作用,特别是改善内皮功能与抗炎作用。值得关注的是,近年来的研究发现,他汀类药物在败血症的预防与治疗中可能具有一定效果,其确切疗效还有待于设计严谨的大规模临床试验证实,但这些发现至少给予我们一个重要启迪：[第一段]     

Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic–ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation.     

Relation between activities of the cortex and vibrissae muscles during high-voltage rhythmic spike discharges in rats

Paroxysmal 5- to 12-Hz high-voltage rhythmic spike (HVRS) activities, which are accompanied by whisker twitching (WT), are found in Long Evans rats, but the function of these HVRS activities is still debated. In four major functional hypotheses of HVRS discharges, i.e., alpha tremor, attention/mu rhythm, idling/mu rhythm, and absence seizure, the first two hypotheses emphasize WT behavior in HVRS bouts. Whisker movement is primarily determined by activation of intrinsic and extrinsic muscles. To clarify the role of WT in HVRS activities, simultaneous recording of the activities from the cortex and intrinsic/extrinsic and neck muscles were performed. Most HVRS bouts (68.8%) revealed no time-locked WT behavior in a 2-h recording session. In addition, WT primarily arose from active protraction due to activation of intrinsic muscles followed by passive retraction. A small portion of WT resulted from activation of both vibrissae muscles with dynamic frequency-dependent phase shifts. Onset of the rhythmic vibrissae EMG significantly lagged behind HVRS onset, and the mean duration of vibrissae muscle activity was one-third to a one-half of a HVRS bout. Moreover, a greater number of HVRS bouts were associated with a longer HVRS duration and higher oscillation frequency. Oscillation frequencies of HVRS activities without WT behavior were significantly lower than those with WT. Under peripheral sensory/motor blockade by xylocaine injection, oscillation frequencies of HVRS bouts significantly decreased, but no remarkable changes in the number or duration of HVRS bouts were observed. Compared with vibrissa muscle activity during WT and exploratory whisking, the duration of muscular activity in each cycle was apparently longer during whisking bouts. Based on these results, overemphasis of the role of WT on HVRS activities might not be appropriate. Instead, HVRS discharges may be associated with absence seizure or idling state. In addition, peripheral inputs, including WT, may elevate the oscillation frequency of HVRS bouts. Moreover, different muscular controls may exist between WT and whisking.