DNA damage from polycyclic aromatic hydrocarbons measured by benzo[a]pyrene-DNA adducts in mothers and newborns from Northern Manhattan, the World Trade Center Area, Poland, and China.

Polycyclic aromatic hydrocarbons (PAH), of which benzo[a]pyrene is a representative member, are combustion-related environmental pollutants and include known carcinogens. Laboratory animal studies indicate that the dose of PAHs to the fetus is on the order of a 10th that to the mother and that there is heightened susceptibility to PAH-induced carcinogenesis during the fetal and infancy periods. Carcinogen-DNA adducts, a measure of procarcinogenic genetic damage, are considered a biomarker of increased cancer risk. Here we compare the levels of benzo[a]pyrene-DNA adducts as a proxy for PAH-DNA damage measured in maternal blood and newborn cord blood obtained at delivery in four different populations of mothers (total of 867) and newborns (total of 822), representing a 30-fold range of exposure to ambient PAHs. The populations include residents in Northern Manhattan, participants in a study of the effects of the World Trade Center disaster, residents in Krakow, Poland, and residents in Tongliang, China. Mean adduct concentrations in both maternal and cord blood and the proportion of samples with detectable adducts, increased across the populations [Northern Manhattan < World Trade Center (WTC) < Krakow < Tongliang], consistent with the trend in estimated ambient exposure to PAHs (P < 0.001). For mothers, the means in the respective populations were Northern Manhattan (0.21 adducts per 10(8) nucleotides), WTC (0.23 adducts per 10(8) nucleotides), Krakow (0.28 adducts per 10(8) nucleotides), Tongliang (0.31 adducts per 10(8) nucleotides); the corresponding means in the newborns were Northern Manhattan (0.23), WTC (0.24), Krakow (0.29), Tongliang (0.31). The percentage of mothers with detectable levels of adducts in the respective populations were Northern Manhattan (36.8%), WTC (57.5%), Krakow (72.9%), Tongliang (73.4%); the corresponding percentages among the newborns were Northern Manhattan (42.4%), WTC (60.6%), Krakow (71.1%), Tongliang (79.5%). Despite the estimated 10-fold lower PAH dose to the fetus based on laboratory animal experiments, the adduct levels in the newborns were similar to or higher than in the mothers. This study suggests that the fetus may be 10-fold more susceptible to DNA damage than the mother and that in utero exposure to polycyclic aromatic hydrocarbons may disproportionately increase carcinogenic risk. The data support preventive policies to limit PAH exposure to pregnant women and children.     

亚急性甲状腺炎的CT诊断

目的:探讨亚急性甲状腺炎的CT表现和特点,提高对该病影像表现的认识。材料和方法:回顾性分析10例亚急性甲状腺炎CT影像特征及临床资料,共16个病灶,其中9例经手术病理证实,1例临床证实。同时抽取局限型甲状腺癌65例,就部分征象作对照分析。结果:亚急性甲状腺炎局限性3例,弥漫性7例。CT表现分3型:①局限于甲状腺一侧叶的低密度病变,病变甲状腺肿大,峡部可受累,3例;②甲状腺两叶各有一低密度病变,呈不对称肿大,病灶之间有正常甲状腺组织,6例共12个病灶;③甲状腺两叶及岬部均匀肿大,略不对称,1例。CT平扫病变为低密度,增强扫描后呈轻到中度均匀强化(15/16),腺内更低密度结节少见(1/16)。病变处甲状腺边缘模糊(16/16),与正常甲状腺组织界限不清(15/16),而局限型甲状腺癌病灶与正常甲状腺腺组织分界清楚(62/65),两者极不一样(P<0.01)。结论:亚急性甲状腺炎CT表现有一定特点,熟悉这些特点对于诊断及鉴别诊断很有帮助。     

Focus cleaning using mini-thoracotomy for cavitary pulmonary tuberculosis or pulmonary tuberculoma: case study of 18 human subjects

Zusammenfassung GRUNDLAGEN: Das Ziel dieser Untersuchung war, die Machbarkeit und Wirksamkeit der Fokus-Sanierung via Mini-Thorakotomie zur Therapie einer kavernösen Lungentuberkulose zu prüfen. METHODIK: Der Mini-Thorakotomie-Zugang wurde in 18 Patienten angewendet (Alter, 25–75 Jahre; median, 47,5 Jahre). Die Patienten hatten eine kavernöse Lungentuberkulose oder ein Lungentuberkulom nach tuberkulostatischer Therapie oder waren Patienten, die auf diese Therapie nicht angesprochen haben. 8 Patienten mit chronischer kavernöser Lungentuberkulose und 10 Patienten mit Tuberkulom haben sich der Fokus-Sanierung, Spülung und Faltnaht unterzogen. ERGEBNISSE: Es gab keine operative Mortalität. Alle Patienten waren klinisch saniert, hatten keinen Nachweis für Bakterien im Sputum, im Röntgen hatten die Lungenschatten abgenommen. Die Dauer der Operation betrug 30–120 min (median, 75 min), der intraoperative Blutverlust war 100–200 ml (median, 153 ml). Der postoperative Spitalsaufenthalt betrug 21–42 Tage (median, 30 Tage). Das Follow-up nach 1–4 Jahren (median, 2,5 Jahre) zeigte keine Komplikation und kein Rezidiv der Grunderkrankung. SCHLUSSFOLGERUNGEN: MTFC ist eine sichere und technisch machbare Methode zur Therapie der Lungentuberkulose oder des Tuberkuloms bei Schonung der Lungenfunktion.     

pcD2/hVEGF对缺血皮瓣存活的影响

目的 观察并探讨pcD2/hVEGF对缺血皮瓣血循环重建和皮瓣存活率的影响.方法 SD大鼠24只,分2组,每组12只.在鼠背部制作蒂位于尾侧的缺血皮瓣(7cm×1cm).实验组皮下注射pcD2/hVEGF,对照组皮下注射生理盐水,术后7天观察皮瓣存活面积比、单位面积微血管计数和及VEGF基因表达水平.结果 2组中pcD2VEGF组皮瓣存活面积比、单位面积微血管密度与对照组有显著性差异.结论 pcD2VEGF能促进缺血皮瓣存活.     

细胞移植的人嗅鞘细胞培养方法的研究

目的探讨适用于细胞移植的人嗅鞘细胞（OECs）分离与培养的方法。方法无菌条件下取自愿捐献孕5个月流产胎儿的完整嗅球进行嗅鞘细胞提取分离、纯化，并对嗅鞘细胞进行免疫组化染色及纯度检测，观察其形态学特点，检测其免疫组化染色的阳性率。结果本方法分离、培养的嗅鞘细胞大多呈三角形、梭形，有些突起较长，生长活跃，增殖迅速，P75、胶质纤维酸性蛋白（GFAP）免疫组化染色呈阳性，嗅鞘细胞阳性率为95．3％。结论该方法简便易行且不影响细胞功能，适用于细胞移植的研究。     

Utility of the coefficient of determination (r2) in assessing the accuracy of interspecies allometric predictions: illumination or illusion?

The appropriateness of relying on the coefficient of determination (r(2)) as a statistical metric for judging the predictability of human clearance (CL) based on interspecies animal data was assessed. An explicit mathematical expression was derived for r(2) as a function of species body weight and the corresponding measured value of CL. The derived mathematical function demonstrated that r(2) is numerically large in most instances. Simulations using random CL generated from a common combination of species of mouse, rat, and monkey resulted in an r(2) of 0.75 as the minimum, and 0.95 and 0.98 at 50th and 75th percentiles, respectively, given that total CL values increase with increasing species body weight. Analysis of literature data also indicated that the prediction accuracy of human CL was not correlated with values of r(2). Therefore, it is concluded that r(2) is a limited statistical measure when assessing allometric scaling for the purpose of predicting human CL.     

TNF-α和低氧对胰腺癌细胞表达VEGF-A、C的调节

目的:探讨细胞活素肿瘤坏死因子-α(TNF-α)、SNAP(S-Nitroso-Nacetyl-penicillamine)对胰腺癌细胞产生血管内皮生长因子A、C(VEGF-A、C)的调节.方法:用Northern杂交和Western杂交法分析6种人胰腺癌细胞株中VEGF-A、C基因和蛋白的表达;以TNF-α或SNAP刺激其中两个细胞株后用逆转录-聚合酶链式反应技术(RT-PCR)分析其VEGF-A、C基因的表达.结果:Northern杂交法显示这6种胰腺癌细胞株均有4.1kb VEGF-A基因和2.4kb VEGF-C基因的表达;Western杂交法显示它们均有分子量为43kD的VEGF-A蛋白质和分子量为55kD的VEGF-C蛋白质的表达.RT-PCR分析法显示:TNF-α使细胞株COLO-357产生VEGF-A、VEGF-C mRNA分别减少约1～2.5倍、1～2倍,使细胞株CAPAN-1产生VEGF-A、VEGF-C mRNA分别减少约1倍、1.6～2.5倍;而SNAP刺激细胞株COLO-357产生VEGF-A mRNA增加约5倍,刺激细胞株CAPAN-1产生VEGF-A mRNA增加约4倍,但对这两种细胞株产生VEGF-C mRNA均无明显刺激作用.结论:细胞活素TNF-α和低氧通过调节血管内皮生长因子A、C的表达而影响胰腺癌细胞的生物学特性,抑制癌细胞的增殖,促进其凋亡、死亡或进展、恶化.     

ULTRASTRUCTURAL INVESTIGATION OF EXPERIMENTAL FRACTURE HEALING ROLE OF OSTEOGENESIS PLAYED BY FIBROBLASTS

Transmission electron microscopic investigation of standardized fractures of radii in 50 rabbits re vealed that fibroblasts took part in the formation of bony callus. The osteogenetic role played by the fibroblasts can be categorized into the following 5 aspects: a. Fibroblasts synthesize and secrete Type collagen fibrils and induce deposition of calcium salt crystals in the collagen fibrils. b. Fibroblasts produce matrix vesicles in their surroundings. These matrix vesicles become calcified and turn into floccu- lent calcospherules which coalesce and fuse into bone tissues. c. Fibroblasts harbor calcium granules in their mitochondria, thus providing calcium for calci- fication of the intercellular matrix and bone forma tion between the cells. d. Fibroblasts can transform directly into osteocytes; there is bone formation around the fibroblasts, the bone tissues surround the fibroblast in the form of bony lacuna, then the fibro- blast in the lacuna transforms into osteocyte. e. Fibroblasts can undergo degenerative changes leading to decease and replacement by bone tissues.     

改制先改革,改革先改人宿迁医改的政府内应力

“人民,是创造历史的真正动力”——壮哉斯言；“真理,只掌握在少数人手中”——诚哉斯言。尽管发生在苏北宿迁的这场席卷城乡的改革,绝不可能只由少数精英分子独立完成,但最初的推动力,是全民意志的厚积薄发?是少数精英的灵光一闪?抑或是一场上级授权、政府定规、全民参与的社会实验?     

Schedule-induced cocaine drinking: choice between cocaine and vehicle

Rats were exposed to daily 3-hr schedule-induced polydipsia sessions (fixed-time 1-min food-pellet delivery) with two drinking fluids available: cocaine solution and water. Fluid position was alternated daily. Polydipsia occurred mostly from a preferred-side spout (position preference) until cocaine solution concentration was increased to between 0.52 and 1.04 mg/ml and animals drank mostly water. Within a lower concentration range (0.28-0.6 mg/ml) maximum session cocaine intakes ranged from 54.3 to 120.1 mg/kg. Postsession serum cocaine levels were about 200 ng/ml. At individually chosen cocaine solution concentrations, the addition of saccharin to the solution did not increase cocaine intake, but a compound solution (saccharin plus glucose) did. With progressive dilution of the compound vehicle, an almost complete preference for cocaine solution was maintained. But with a return to water as the vehicle, animals reverted to a position preference after a few sessions, although one maintained a clear cocaine preference. Schedule-induced polydipsia produced chronic, oral self-administration of cocaine resulting in pharmacologically significant intakes and serum levels.