Density of tumor-associated macrophages correlates with lymph node metastasis in papillary thyroid carcinoma

Background: Tumor-associated macrophages (TAMs) have recently been recognized as being important players in the tumoriogenesis of many cancers, including advanced thyroid cancer. However, a role in papillary thyroid carcinoma (PTC), the most prevalent thyroid cancer, has not been established. We hypothesized that TAMs also facilitate tumor progression in PTC. Methods: We investigated TAMs density in both benign thyroid lesions and PTC tumors by CD68 immunostaining. CD68-positive cell density was further associated with the clinicopathological characteristics of PTC patients. Finally, TAMs were isolated from PTC tumors and phenotyped by cytokine and receptor profiling. Results: The overall density of TAMs was found to be significantly higher in PTC tumors, compared with thyroid goiter and follicular adenoma. The density of TAMs was positively associated with lymph node metastasis in TNM (tumor-node-metastasis) stages III/VI compared with stages I/II. No association was observed in other common tumor features, including the BRAF mutation. The isolated TAMs presented with high levels of M2-associated cytokine and receptors, making M2 the predominant TAM phenotype. Conclusions: TAMs may play a functional role in the progression of PTC.     

Effects of avermectins on neurite outgrowth in differentiating mouse neuroblastoma N2a cells

Avermectins (AVMs) are macrocyclic lactone compounds that have been widely used as parasiticides in veterinary and human medicine and as pesticides in agriculture and horticulture. The multidrug resistance transporter, P-glycoprotein (P-gp), is associated with the efflux transport of AVMs and other drugs across the blood–brain and placental barrier, and plays an important role in attenuating the neurotoxicity and developmental toxicity of AVMs. In this study, the mouse neuroblastoma N2a cell line was used to investigate the neurotoxicity of two AVM derivatives: abamectin (ABM) and doramectin (DOR). We found that both these compounds caused significant dose-dependent inhibition of neurite growth in differentiating N2a cells. In addition, Western blotting analysis showed that ABM and DOR significantly inhibited the expression of not only P-gp but also the cytoskeletal proteins, β-actin and β-tubulin. This suggests ABM and DOR may inhibit neurite growth by down-regulating the expression of P-gp and cytoskeletal proteins. Furthermore, knockdown of P-gp expression by RNA interference in N2a cells reduced neurite growth even in the absence of ABM and DOR, and reduced it even more in the presence of low levels of these compounds. These results suggest that even subcytotoxic levels of ABM and DOR can be neurotoxic in differentiating cells and that this neurotoxicity may, at least in part, be the result of the down-regulation of P-gp and cytoskeletal proteins.     

利用同源重组建立CHO高表达细胞株

目的:利用同源重组的方法,克服基因组位置效应,建立CHO高表达细胞株.方法:通过弱化筛选基因,构建了一系列弱化筛选基因的载体,大规模筛选CHO基因组,寻找转录活跃区,并在此基础上构建同源重组载体系统,包括标记载体pExplorer和打靶载体pTarget.结果:利用带有弱化筛选基因的标记载体pExplorer寻找到了基础转录水平较高,并且适于加压的细胞克隆,报告基因UK的表达量在加压后稳定在10 μg·ml-1·24 h-1·10-6细胞.然后通过载体pTarget实现了在CHO细胞中的同源重组.结论:通过同源重组的方法,有效地克服了基因组位置效应,为建立哺乳动物高表达细胞株提供了一个新的更加有效的途径.     

人CD20胞外区与噬菌体pⅢ融合基因在E.coli中的可溶性表达

目的 :克隆人CD2 0胞外区基因 (cdw)和丝状噬菌体 (M13K0 7)G3蛋白N端结构域 (pⅢN1)基因 ,并在大肠杆菌中进行高效融合表达。方法 :利用逆转录PCR和PCR方法分别克隆CD2 0胞外区基因和pⅢN1基因 ,然后将二者融合克隆入pTIG Trx表达载体 ,在大肠杆菌中进行可溶性表达。结果 :可溶性表达产物占细菌可溶性蛋白的约2 5 % ,表达产物可被抗CD2 0分子的单克隆抗体识别。结论 :成功地表达并鉴定了人CD2 0胞外区蛋白 ,为利用噬菌体抗体库进行抗CD2 0抗体的筛选奠定了基础。     

人宫颈鳞状细胞癌裸鼠移植模型的建立及分析

目的:采用裸鼠腹部皮下移植感染高危型HPV人宫颈鳞癌组织的方法,建立宫颈癌动物模型,研究其在裸鼠体内的成瘤性,并探讨其生物学特性。方法:取中分化及高分化人宫颈鳞状细胞癌癌组织两块分别接种于裸鼠腹部皮下,以建立人宫颈癌裸鼠模型,比较两组荷瘤鼠成瘤率、一般特性和移植瘤生长情况,85天后处死裸鼠,切除肿块做病理切片;PCR(聚合酶链式反应)检测肿瘤组织、外周血和肝等脏器HPV DNA表达情况。结果:接种后两组小鼠分别于第42天及第49天在接种部位可见结节,第80天后肿瘤块平均体积分别为(38.0±5.1)mm3、(30.2±4.6)mm3,肿瘤移植成功率分别为80%及60%,移植瘤生长以局部浸润为主,未见转移瘤。组织学检查所有移植瘤与种植前肿瘤组织病理检查结果一致,HPV DNA呈阳性,且为高危型人乳头瘤病毒HPV16、18型阳性,亦与原宫颈癌病人HPV16、HPV18感染一致;外周血与肝等脏器HPV DNA呈阴性。结论:裸鼠人宫颈癌组织模型成瘤率较高,且分化程度越低其成瘤率越高,操作简便,成本低,且保留了HPV感染生物学特性,为探索宫颈癌的发病机制和临床治疗提供了重要的科研工具。     

Creutzfeldt-Jakob disease: heat shock protein 70 mRNA levels in mononuclear blood cells and clinical study

Prion diseases such as Creutzfeldt-Jakob disease (CJD) are associated in most cases with the accumulation of an unusual isoform of prion protein (PrP^SC). PrP^SC is derieved from the abnormal folding of the cellular isoform of prion protein (PrP^C). On the other hand, heat shock protein is known to ensure proper protein assembly and folding and to facilitate proteolytic digestion of abnormal or denatured proteins. Many studies have therefore hypothesized that heat shock protein is linked to prion disease. We examined the relationship between heat shock protein HSP70 and prion disease in CJD patients. HSP70 mRNA levels in mononuclear blood cells (MBCs) were compared in 14 CJD patients (10 confirmed by histo-pathological study), 12 vascular dementia (VD) patients, 16 patients with Parkinson's disease and dementia (PD) and 14 nondemented control subjects. The possible correlation between HSP70 mRNA expression levels and clinical findings was also evaluated. HSP70 mRNA expression levels in MBCs were measured by northern blotting. HSP70 mRNA levels in MBCs from patients with CJD were significantly higher than those from patients with VD or PD and in nondemented controls. Age at symptom onset, dementia severity, disease duration and neuroimaging grade of CJD patients were not correlated with relative HSP70 mRNA levels. No significant relationship between HSP70 mRNA levels and aging was found. These results suggest that measurement of HSP70 mRNA in MBCs might provide an auxiliary tool for the diagnosis of CJD. Received: 21 June 2999 / Received in revised form: 16 March 2000 / Accepted: 3 May 2000     

Protection with a recombinant Hc of Clostridium Botulinum neurotoxin serotype A from Escherichia coli as an effective subunit vaccine

A recombinant Hc of Clostridium botulinum neurotoxin serotype A (AHc) was successfully expressed in Escherichia coli for use as an antigen, and the purified AHc was used to vaccinate mice and evaluate their survival against challenge with active botulinum neurotoxin serotype A. The mice, given twice or third subcutaneous vaccinations with a dosage of 1 microg AHc mixed with Freund adjuvant, were completely protected against an intraperitoneal administration of 1,000,000 50% lethal doses (LD(50)) of neurotoxin serotype A. Following the administration of AHc using alhydrogel adjuvant via the intramuscular route, a strong protective immune response was also elicited in the vaccinated mice. A dose-response was observed in protective efficacy with increasing AHc dosage and number of vaccinations. Mice that received two injections of >or= 0.2 microg and three injections of >or= 0.04 microg were completely protected when challenged with 100,000 LD(50) of neurotoxin serotype A. These results clearly suggest that the recombinant AHc highly expressed in Escherichia coli is very efficacious in protecting against challenge with active botulinum neurotoxin serotype A in mouse model and a good subunit candidate vaccine against botulinum neurotoxin serotype A for human use.     

Preparation and antibacterial test of chitosan/PAA/PEGDA bi-layer composite membranes

Chitosan/poly(acrylic acid)/poly(ethylene glycol) diacrylate (PEGDA) composite membranes with a bi-layer configuration were prepared and their potential application as an antibacterial material was examined. A two-step process was adopted. A dope consisting of PEGDA, acrylic acid (AA) and a photoinitiator was cast and then UV-cured on a glass substrate to form a mechanically strong, dense membrane. Subsequently, the membrane was coated with a layer of solution composed of chitosan, AA and water. As the majority of AA diffused downwards into the supporting layer underneath, chitosan coagulated with residual AA to form a nano-layer on the top surface by means of UV irradiation. Low-voltage field-emission scanning electron microscopy was used to observe the membrane morphology and to measure the thickness of the top layer. Contact angle measurements indicated a top layer mixed with chitosan and poly(acrylic acid), which was confirmed by chemical composition analysis of X-ray photon spectroscopy. The antibacterial activities of the formed membranes were tested both with respect to a Gram-negative (Escherichia coli) and a Gram-positive (Staphylococcus aureus) bacteria.     

Co-expression of tetanus toxin fragment C in Escherichia coli with thioredoxin and its evaluation as an effective subunit vaccine candidate

The receptor-binding domain of tetanus toxin (THc), which mediates the binding of the toxin to the nerve cells, is a candidate subunit vaccine against tetanus. In this study one synthetic gene encoding the THc was constructed and highly expressed in Escherichia coli by co-expression with thioredoxin (Trx). The purified THc-vaccinated mice were completely protected against an active toxin challenge in mouse models of disease and the potency of two doses of THc was comparable to that of three doses of toxoid vaccine. And a solid-phase assay showed that the anti-THc sera inhibited the binding of THc or toxoid to the ganglioside GT1b as the anti-tetanus toxoid sera. Furthermore, mice were vaccinated once or twice at four different dosages of THc and a dose-response was observed in both the antibody titer and protective efficacy with increasing dosage of THc and number of vaccinations. The data presented in the report showed that the recombinant THc expressed in E. coli is efficacious in protecting mice against challenge with tetanus toxin suggesting that the THc protein may be developed into a human subunit vaccine candidate designed for the prevention of tetanus.     

Obstetrical Disease Spectrum in China: An Epidemiological Study of 111,767 Cases in 2011

Background:

No national research on maternal and fetal complications and outcomes has been carried out in the mainland of China in recent years. This study was to provide a scientific basis for better control of obstetrical and neonatal diseases and better allocation of medical resources by analyzing the epidemiological characteristics of obstetrical diseases in the mainland of China.

Methods:

Hospitalized obstetrical cases from 19 tertiary and 20 secondary hospitals in 14 provinces (nationally representative) during the period January 1, 2011 to December 31, 2011 were randomly selected. The general condition, pregnancy complications, and perinatal outcomes of the patients were studied.

Results:

The top five medical and surgical complications of pregnant women in the mainland of China were anemia (6.34%), uterine fibroids (2.69%), thyroid disease (1.11%), thrombocytopenia (0.59%), and heart disease (0.59%). The incidences of premature rupture of membranes (PROM), preterm birth, prolonged pregnancy, hypertensive disorders complicating pregnancy (HDCP), multiple pregnancy, intrahepatic cholestasis of pregnancy (ICP), placenta previa, placental abruption, postpartum hemorrhage, and amniotic fluid embolism were 15.27%, 7.04%, 6.71%, 5.35%, 1.57%, 1.22%, 1.14%, 0.54%, 3.26% and 0.06%, respectively. The incidences of anemia and prolonged pregnancy were significantly lower in tertiary than secondary hospitals (P < 0.001), whereas the incidence of uterine fibroids, thyroid diseases, thrombocytopenia, heart disease, PROM, preterm birth, HDCP, multiple pregnancy, ICP, placenta previa, and placental abruption were significantly higher in tertiary than secondary hospitals (P < 0.001). The cesarean section (CS) rate was 54.77%. The newborn sex ratio was 119:100, and 1.03% of the neonates were malformed. The percentages of low birth weight and fetal macrosomia in full-term babies were 2.10% and 7.09%, respectively.

Conclusions:

The incidence of some obstetrical diseases is still high in the mainland of China. The CS rate is much higher than World Health Organization recommendations, in which CS delivery by maternal request (CDMR) accounted for a large proportion. The government should propose solutions to reduce CS rate, especially the rate of CDMR. Most obstetrical complications have higher incidence in tertiary hospitals compared with secondary hospitals. It is important to manage the health of pregnant women systematically, especially those with high-risk factors.