The Pichia pastoris HIS4 gene: nucleotide sequence,creation of a non-reverting his4 deletion mutant,and development of HIS4-based replicating and integrating plasmids

We have obtained a clone of the Pichia pastoris HIS4 gene and have determined its nucleotide sequence. Based upon its deduced amino-acid sequence, the product of the P. pastoris HIS4 gene has the same structural organization as the Saccharomyces cerevisiae His4 protein and appears to encode a trifunctional enzyme catalyzing the second (phosphoribosyl-ATP pyrophosphohydrolase), third (phosphoribosyl-AMP cyclohydrolase), and tenth (histidinol dehydrogenase) steps in histidine biosynthesis. The chromosomal copy of the HIS4 gene was disrupted by homologous recombination, creating the strain SGY58. The his4 deletion mutation in this strain lacks the entire coding region of this gene and has a reversion rate that is undetectable. A set of complementary plasmids that carry the HIS4 gene was also developed. Among these are nine E. coli-P. pastoris shuttle vectors that transform the His4 deletion mutant at high efficiency and an integration vector for creating site-specific alterations of the P. pastoris genome.     

Evaluation of serum type III procollagen peptide as an exposure marker in retired coal workers

Serum type III procollagen peptide (PIIIP), a degradation product of the type III collagen precursor, has been put forward as an exposure marker for mineral dust. We evaluated PIIIP levels as a marker of exposure to and effects of coal dust in retired coal miners (n = 104). To this end: (a) the individual cumulative dust exposure was calculated from job-exposure matrices, and (b) in addition to routine chest radiography (CR) of all miners according to the criteria of the International Labour Organisation (ILO), a subgroup (n = 46) was screened by high-resolution computed tomography (HRCT). Profusion score (CR and HRCT) tended to increase with cumulative dust exposure, even in the absence of CR evidence for pneumoconiosis (i.e. CR , 0/1, n = 35). In contrast to our previous findings in active miners, PIIIP levels were not increased in miners as compared with non-dust-exposed controls (n = 29), and no differences were observed between miners without (ILO = 0/0) and miners with coal workers' pneumoconiosis (CWP; ILO 0/1). No trend in PIIIP versus pneumoconiosis stage was present, either by CR or by the more sensitive HRCT score. PIIIP was also unrelated to any lung function parameter (FEV₁, FVC, impedance, diffusion capacity). Age, medication, medical history and smoking habits had no significant effect on PIIIP levels. In the miners with CWP (i.e. ILO > 0/0, n = 28) a significant negative correlation was present between PIIIP values and (log) cumulative dust exposure. This decrease in serum PIIIP levels with increasing cumulative exposure may be due to chronic adaptive changes in type III collagen deposition and/or breakdown. Other relations between exposure and PIIIP were not observed. In conclusion, the present findings do not support the use of serum type III procollagen peptide as a marker of exposure to and (early) interstitial or respiratory effects of coal dust.     

Serum tumor marker kinetics and the clinical course of patients with advanced breast cancer

Serum carcinoembryonic antigens (CEA), CA 15-3, and tissue polypeptide antigens (TPA) have been used in monitoring the clinical course of patients with breast cancer. However, recent reports have suggested that the serial levels of these markers during therapy do not always correlate with the response to therapy. To clarify the usefulness of the serial combination assay of these markers in monitoring the clinical course of patients during therapy, we investigated the relationship between the initial changes and the kinetic patterns of the markers after therapy and the objective responses. When an increase or decrease of over 20% in these markers is taken to be significant, then the initial changes in all three markers significantly correlated with the therapeutic responses (P<0.01). Five distinct kinetic patterns in the marker levels were observed. A paradoxical kinetic pattern of CEA and CA 15-3 levels — that is, an initial surge and subsequent drop — was seen in one-third of the responders. The TPA levels tended to exhibit a steady decline pattern in those responders. The sensitivity and specificity of the kinetic patterns to predict the clinical courses were significantly higher than those obtained from the analysis of initial changes. These findings thus suggest that adequate knowledge of the unique kinetics of each marker may help to make a more accurate prediction of the therapeutic responses.     

恶性纤维组织细胞瘤的免疫组织化学研究

本文对23例恶性纤维组织细胞瘤((MFH)及19例其他软组织肿瘤的免疫组化研究表明,AACT,AAT阳性率最高,是肿瘤性组织细胞的良好标志物,对MFH有一定诊断价值。Lys不是恶性组织细胞的良好标志物。Des的表达提示部分肿瘤细胞向肌纤维母细胞分化,Vim的表达则提示向纤维母细胞分化。所以,我们的研究结果表明MFH可能来自未分化间叶细胞,并在不同情况下向组织细胞、纤维母细胞和肌纤维母细胞等不同方向分化,而表现出复杂的组织学形态。     

Immunological comparison between prostate-specific antigen and γ-seminoprotein

Summary Prostate-specific antigen (PA) and -seminoprotein (-Sm) were compared by immunocytochemical, immunodiffusion and immunoblotting methods using rabbit anti-PA antibody and rabbit anti--Sm antibody. Enzyme immunoassys (EIAs) were developed for measurements of PA and -Sm to determine a correlation between serum PA and -Sm levels in patients with prostate cancer. The patterns of localization and distribution of PA and -Sm were identical in prostate tissue sections, including benign and cancerous human prostacs. The immunodiffusion study showed that the antigens with which anti-PA antibody and anti--Sm antibody reacted in seminal plasma and prostate tissue homogenates were identical to each other. In the immunoblotting study, anti-PA antibody and anti--Sm antibody recognized a single antigen corresponding to a molecular weight of approximately 33,000 both in seminal plasma and prostate tissue homogenates. The EIAs developed in this study were sensitive, specific, and reproducible, and the correlation between serum PA and -Sm values determined by these EIAs was highly significant (r=0.99, P(0.001). These results indicated that PA and -Sm were immunologically identical and that serum PA and -Sm determined by immunoassays using anti-PA antibody and anti--Sm antibody should be evaluated as identical tumor markers for serodiagnosis of prostate cancer.     

Prenatal diagnosis for paediatricians

In Ontario, approximately 140,000 women deliver newborn infants each year. Of these women, 60,000 to 70,000 have multiple marker screening, 10,000 undergo amniocentesis or chorion villus sampling and virtually all have at least one prenatal ultrasound. Multiple marker screening is not used in every province and territory; however, amniocentesis and prenatal ultrasound are used throughout Canada. Most paediatric patients will have been exposed to some form of prenatal diagnosis. If an abnormality is found prenatally, parents may have concerns to discuss with the paediatrician after the child is born. Likewise, if a child with a problem is born following a normal pregnancy, the parents will want to know why the problem was missed prenatally. Paediatricians should be aware of prenatal tests that have been performed to understand better their patients and their families.     

211例患者胸腹水中TSGF检测结果分析

目的　比较恶性肿瘤患者、非恶性肿瘤患者以及恶性肿瘤患者治疗前后胸腹水中 TSGF含量的关系 ,探讨胸腹水中 TSGF含量对恶性肿瘤的早期诊断及治疗意义。方法　对 4 6例非急性炎症和非结核类患者 (对照组 )、5 8例急性炎症和结核患者、1 0 7例恶性肿瘤患者 (治疗前 )及治疗后 4 5例恶性肿瘤患者的胸腹水分别进行 TSGF含量测定 ,比较各组的差异。结果　对照组的阳性率是 4 .3% ,急性炎症和结核患者组的阳性率是 81 .0 % ,与对照组有显著差异 (t=1 0 .7,P<0 .0 1 ) ;恶性肿瘤患者组的阳性率为 86 .9% ,与对照组有显著差异 (t=1 2 .4 ,P<0 .0 1 ) ,但与急性炎症和结核患者组无显著差异 (t=0 .0 1 ,P>0 .0 5 ) ;恶性肿瘤患者组治疗前与治疗后有显著差异(t=4 .5 ,P<0 .0 1 )结论　测定胸腹水中 TSGF含量对恶性肿瘤的早期诊断、疗效观察有着重要的意义     

多种肿瘤标志物蛋白芯片检测系统对恶性肿瘤的临床应用价值

 目的　研究多种肿瘤标志物蛋白芯片检测系统对恶性肿瘤诊断的临床意义。方法　用该检测系统测定分析 4 6 9例恶性肿瘤患者 ,130例良性疾病患者和 14 4 8例健康查体者血清中 12种常见肿瘤标志物 (CA199,NSE ,CEA ,CA2 4 2 ,CA12 5 ,CA15 3,AFP ,Ferrtin ,free PSA ,PSA ,β HCG及HGH)的水平。结果　恶性肿瘤组的阳性率为 81.4 5 % ,显著高于良性疾病组 (5 0 .0 0 % )和健康查体组 (2 9.77% ) (P <0 .0 5 )。除胰腺癌之外 ,联合检测对其余 14种恶性肿瘤的敏感性均显著高于单一标志物检测 (P <0 .0 5 )。结论　运用蛋白芯片技术联合检测多种肿瘤标志物可以明显提高恶性肿瘤诊断的敏感性 ,同时也可以作为无症状人群的早期肿瘤普查手段之一 ,尤其对肿瘤高危人群的防癌普查具有一定意义。     

多种肿瘤标志物蛋白芯片检测系统对肺癌的诊断价值

目的　研究多种肿瘤标志物蛋白芯片检测系统对肺癌的诊断价值。方法　用该检测系统测定10 8例肺癌患者、48例肺良性病变患者和 14 5例正常人血清中 12种肿瘤标志物 (CA199,NSE ,CEA ,CA2 42 ,CA12 5 ,CA15 3 ,AFP ,ferritin ,free PSA ,PSA ,β HCG及HGH)的水平。 结果　肺癌组的芯片阳性率为 83 .3 3 %( 90 / 10 8) ,显著高于肺良性病变组 ( 5 2 .0 8% ,2 5 / 48)和健康组 ( 2 8.97% ,42 / 14 5 ) (P <0 .0 0 1) ;肺癌不同分期组间阳性率存在显著性差异 ,以Ⅳ期肺癌组阳性率最高 (P =0 .0 48) ,但不同病理类型肺癌组间无显著性差异(P =0 .5 19) ;不同分期之间CA199、CEA以及CA2 42血清水平存在显著性差异 (P =0 .0 41,P =0 .0 18和P =0 .0 0 2 ) ;CEA阳性率以腺癌组最高 ,与其它组织学类型肺癌比较无显著性差异 (P =0 .0 7) ;NSE阳性率以小细胞肺癌组最高 (P <0 .0 0 1) ;联合检测在提高诊断敏感性的同时 (P <0 .0 0 1) ,特异性有所下降 (P <0 .0 0 1)。结论　运用蛋白芯片联合检测多种血清肿瘤标志物可明显提高肺癌诊断的敏感性 ,同时对于确定其临床分期 ,鉴别病理类型以及监测疗效均有一定的意义。由于该法特异性及阳性预测值偏低 ,更适合于无明显症状的门诊患者和肺癌高危人群的筛查。