In vivo PET imaging of cardiac presynaptic sympathoneuronal mechanisms in the rat.

The sympathetic nervous system of the heart plays a key role in the pathophysiology of various cardiac diseases. Small-animal models are valuable for obtaining further insight into mechanisms of cardiac disease and therapy. To determine the translational potential of cardiac neuronal imaging from rodents to humans, we characterized the rat sympathetic nervous system using 3 radiotracers that reflect different subcellular mechanisms: (11)C-meta-hydroxyephedrine (HED), a tracer of neuronal transport showing stable uptake and no washout in healthy humans; (11)C-phenylephrine (PHEN), a tracer of vesicular leakage and intraneuronal metabolic degradation with initial uptake and subsequent washout in humans; and (11)C-epinephrine (EPI), a tracer of vesicular storage with stable uptake and no washout in humans. METHODS: We used a small-animal PET system to study healthy male Wistar rats at baseline, after desipramine (DMI) pretreatment (DMI block), and with DMI injection 15 min after tracer delivery (DMI chase). The rats were kept under general isoflurane anesthesia while dynamic emission scans of the heart were recorded for 60 min after radiotracer injection. A myocardial retention index was determined by normalizing uptake at 40 min to the integral under the arterial input curve. Washout rates were determined by monoexponential fitting of myocardial time-activity curves. RESULTS: At baseline, HED showed high myocardial uptake and sustained retention, EPI showed moderate uptake and significant biphasic washout, and PHEN showed moderate uptake and monoexponential washout. The average (+/- SD) left ventricular retention index for HED, PHEN, and EPI was 7.38% +/- 0.82%/min, 3.43% +/- 0.45%/min, and 4.24% +/- 0.59%/min, respectively; the washout rate for HED, PHEN, and EPI was 0.13% +/- 0.23%/min, 1.13% +/- 0.35%/min, and 0.50% +/- 0.24%/min, respectively. The DMI chase resulted in increased washout only for HED. DMI block decreased myocardial uptake of all tracers by less than 90%. CONCLUSION: Kinetic profiles of HED in the rat myocardium were similar to those of HED in humans, suggesting comparable neuronal transport density. Unlike in humans, however, significant washout of EPI and faster washout of PHEN were encountered, consistent with high intraneuronal metabolic activity, high catecholamine turnover, and reduced vesicular storage. This evidence of increased neuronal activity in rodents has implications for translational studies of cardiac neuronal biology in humans.     

Bone growth patterns in Chinese children and adolescents: a 6-year follow-up study provides evidence for sexual dimorphism and tracking

Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up. Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences. Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at baseline and a 6-yr follow-up. Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”. Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr, but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs. Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores the importance that osteoporosis prevention should begin in childhood and adolescence. Fengxiu Ouyang and Binyan Wang contributed equally to this article. Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National Institute of Health and by the Food Allergy Project.     

对诊断PADAM的游离睾酮指数的评估

目的 评价诊断中老年男子部分雄激素缺乏综合征（PADAM）的游离睾酮指数（FTI）.方法 对129例45岁以上健康男性的FTI进行年龄相关分析.以推算的游离睾酮（CFT）值为依据,对FTI进行有效性检验.结果 男子在中老年期FTI与增龄呈明显的负相关.FTI敏感性97.78%,特异性58.33%.结论 计算简单的FTI可用于PADAM病人的筛选和随访,尤其对70岁以上男子是血清FT较为有效的参数.     

Prenatal diagnosis of Werdnig Hoffmann disease in China

Objective To establish a means for prenatal prediction of spinal muscular atrophy (SMA) through survival motor neuron (SMN) gene deletion analysis and genetic counseling in families with a child affected with SMA.
Methods Genetic analysis for prenatal prediction of Werdnig-Hoffmann disease was performed in a at risk Chinese family by polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) in SMN gene exons 7 and 8.
Results The pregnancy was positive for the homozygous deletion of the SMN gene, thus the fetus was diagnosed as being affected and the pregnancy was terminated.
Conclusion This approach is fast and reliable for DNA-based prenatal diagnosis of Werdnig-Hoffmann disease.     

牙本质黏结剂增强根管倒充填材料密闭性能的实验研究

目的观察在使用MTA进行根尖倒封闭术时,牙本质粘结剂对其密闭抗微渗漏的影响.方法取40颗离体单根恒牙,分别用MTA、MTA 牙本质粘结剂进行根尖倒封闭术,用染料渗透法检测根尖微渗漏的情况.结果MTA 牙本质粘结剂组的根尖密闭效果明显优于单纯使用MTA组,其差别具有统计意义(P<0.05).结论在使用MTA进行根尖倒封闭术时,使用牙本质粘结剂可提高充填体的密闭效果.     

Distribution of rat facial motoneurons and its reorganization following nerve reinnervation]

OBJECTIVE: To examine the distribution of rat facial motoneurons contributing different branches under normal situation and when nerve reinnervation occurred following facial nerve axotomy. METHODS: The normal distribution of motoneurons innervated both buccal and marginal mandibular branches and its reorganization after facial nerve reinnervation was observed using retrograde labeling with fluorescein. RESULTS: Under normal situation, the motoneurons contributing buccall and marginal mandibular branches were primarily distributed in the intermedial and lateral subnucleus in facial nucleus and almost completely overlapped. The two types labeled neurons organized closely, but there were no double-labeled neurons. Although the motoneurons contributing buccall and marginal mandibular branches were primarily overlapped 4 month post-anastomosis, the number of the labeled neurons obviously decreased and the organization got more scattered. There were 10% of buccall branches, 5% of marginal mandibular motoneurons in the dorsal subnuleus, 1% of buccall and 4% of marginal mandibular in dorsal ventral and medial subnucleus. The distribution pattern of the motoneurons 6 month post-anastomosis was similar to that of 4 month post-anastomosis, but the number of the labeled neurons increased, and there were 1%-2% double-labeled neurons. CONCLUSION: The distribution pattern of motoneurons innervated both buccal and marginal mandibular branches indicates that it should exist wide-spread communicating branches, and its reorganization after facial nerve reinnervation suggests that misdirected regeneration occurs among motoneurons innervating different branches.     

Expression of CD68 CD45RO CD20 and proliferating cell nuclear antigen in nasal polyps]

OBJECTIVE: To study the cellular expression of CD45RO, CD20, CD68 and proliferating cell nuclear antigen (PCNA) in nasal polyps. METHODS: Nasal polyp tissues from 50 patients were evaluated for cellular expression of CD45RO, CD20, CD68 and PCNA using immunohistochemistry SP by counting the average number in 5 chosen high-power fields, Histopathological observations were combined with HE. Analyses were performed on SPSS10.0. RESULTS: CD68+ cells were expressed more in nasal polyps dominated by eosinophils than by neutrophils(P < 0.05). There was no difference between CD45RO and CD20, but both of them had negative correlation(P = 0.05). Significant correlation was found between CD68+ cells and eosinophils or PCNA positive cells on epithelium. PCNA positive cells on epithelium had significant correlation on fibroblast (P < 0.05). CONCLUSION: Inflammatory cell infiltration (eosinophilia CD45RO, CD20, CD68) and cell proliferating in epithelium cells, glandular cell and fibroblast are strongly correlated with formation of nasal polyps. The nasal polyps are not only characteristic of eosinophilia but also by lymphocytes dominated by CD45RO and CD68 positive cells. CD68 may be stem cell of nasal polyp.     

深静脉血栓形成患者凝血因子ⅩⅢ Val34Leu基因多态性检测

目的:探讨凝血因子ⅩⅢ(FⅩⅢ)Val34Leu基因多态性与中国人群深静脉血栓形成(DVT)发病的相关性.方法:利用聚合酶链反应和限制性片段长度多态性(PCR-RFLP)方法,检测了103例DVT患者与106例正常对照的FⅩⅢVal34Leu基因多态,并加以对照分析.结果:103例DVT患者FⅩⅢVa134Leu基因型均为野生型V/V,未见突变类型;106例对照组中发现1例突变杂合子V/L.2组基因型频率、等位基因频率相互比较,差异均无统计学意义(P＞0.05).结论:FⅩⅢVal34Leu对中国人群DVT有保护作用的可能性极小.     

对诊断PADAM的血清游离睾酮界限值的初探

目的探寻诊断中老年男子部分雄激素缺乏综合征(PADAM)血清游离睾酮(FT)的界限值。方法根据60例45岁以上健康男性完成伊斯坦布尔症状量表(ISS)与视听性刺激(AVSS)时阴茎勃起监测结果进行分组,计算AVSS勃起功能正常组推算的游离睾酮(CFT)值的参考范围。结果AVSS勃起功能正常组CFT的中位数为0．37(0．20～0．52)nmol/L,异常组的中位数为0．25(0．12～0．40)nmol/L,z=2．25,P＜0．05,差别有显著性意义。两组性功能症状的差别也有极显著性意义(P＜0．01)。CFT的界限值是0．20nmol/L。结论研究用ISS和AVSS勃起功能正常对象的血清FT值,可为诊断PADAM建立界限值。