Recurrent colorectal carcinoma: evaluation with barium enema examination and CT

The efficacy of the barium enema examination and abdominal computed tomography (CT) was investigated in 81 patients who had undergone operation for colorectal carcinoma. Recurrent disease was found in 52 patients and was divided into local (anastomotic and perianastomotic) and remote (distant and hepatic metastases) types. In 32 patients with locally recurrent carcinoma, the sensitivity of the barium enema examination was 88%; for CT it was 69%. Conversely, the barium enema examination was not useful for detecting remote metastases shown on CT, which disclosed disease at one or more sites in 47 (90%) of the 52 patients. CT best evaluated recurrences remote from the anastomosis, pelvic recurrences in patients with colostomies, and hepatic metastases. Barium enema examination and CT were therefore found to be complementary modalities.     

海南粗榧新碱衍生物 HH07A 对 DNA 聚合酶 I 活性的影响

用体外DNA聚合酶I作用下DNA合成的方法,研究HH07A的作用机制。结果表明,HH07A对DNA聚合酶I催化下的DNA合成有明显抑制作用,且在一定浓度范围内存在浓度依赖性。将药物与DNA模板及DNA聚合酶I分别预保温后,发现DNA模板活性无明显改变,而酶的活性则受到显著抑制。提示HH07A对DNA聚合酶I催化下DNA合成的抑制是通过HH07A与DNA聚合酶I直接作用而实现的。     

可逆性胆碱酯酶抑制剂二甲氨基甲酸-[3-(烷氨基)烷氧基-4(5)-叔丁基]苯酯的合成

在催醒安的邻位和对位异构体及其同系物的苯坏上引入烷基后,可以增强抑制胆碱酯酶的活性,我们乃进一步在催醒安及其同系物的苯环不同位置上引入叔丁基,合成了一系列二甲氨基甲酸-[3-(烷氨基)烷氧基-4(5)-叔丁基]苯酯(Ⅰ_(1～13)和Ⅱ_(1～5))(表2),以探索对活性的影响。     

Tellurite effects on Rhodobacter capsulatus cell viability and superoxide dismutase activity under oxidative stress conditions

Cells of the facultative photosynthetic bacterium Rhodobacter capsulatus (MT1131 strain) incubated with 10 microg ml-1 of the toxic oxyanion tellurite (TeO2-(3)) exhibited an increase in superoxide dismutase activity. The latter effect was also seen upon incubation with sublethal amounts of paraquat, a cytosolic generator of superoxide anions (O2-), in parallel with a strong increase in tellurite resistance (TeR). A mutant strain (CW10) deficient in SenC, a protein with similarities to peroxiredoxin/thiol:disulfide oxidoreductases and a homologue of mitochondrial Sco proteins, was constructed by interposon mutagenesis via the gene transfer agent system. Notably, the absence of SenC affected R. capsulatus resistance to periplasmic O2- generated by xanthine/xanthine oxidase but not to cytosolic O2- produced by paraquat. Further, the absence of SenC did not affect R. capsulatus tellurite resistance. We conclude that: (1) cytosolic-generated O2- enhances TeR of this bacterial species; (2) small amounts of tellurite increase SOD activity so as to mimic the early cell response to oxidative stress; (3) SenC protein is required in protection of R. capsulatus against periplasmic oxidative stress; and finally, (4) SenC protein is not involved in TeR, possibly because tellurite does not generate O-2 at the periplasmic space level.     

A simple and rapid approach for screening of SARS-coronavirus genotypes: an evaluation study

Background  

The Severe Acute Respiratory Syndrome (SARS) was a newly emerged infectious disease which caused a global epidemic in 2002–2003. Sequence analysis of SARS-coronavirus isolates revealed that specific genotypes predominated at different periods of the epidemic. This information can be used as a footprint for tracing the epidemiology of infections and monitor viral evolution. However, direct sequencing analysis of a large number of clinical samples is cumbersome and time consuming. We present here a simple and rapid assay for the screening of SARS-coronavirus genotypes based on the use of fluorogenic oligonucleotide probes for allelic discrimination.     

Oral misoprostol for cervical priming in non-pregnant women

Endometrial biopsy and hysteroscopy are important investigations in women presenting with abnormal vaginal bleeding. Endometrial biopsy is often performed as an outpatient procedure by endometrial aspiration. Difficulty in entering the internal cervical os may be encountered, especially in nulliparous women. The same problem may occur during hysteroscopy or dilatation and curettage. It is well known that use of a cervical priming agent is effective in reducing complications during cervical dilatation in pregnant women. However, its use in non-pregnant women is not well established. We compared oral misoprostol versus placebo for a cervical priming effect in non-pregnant women prior to hysteroscopy. The cumulative force required for cervical dilatation was significantly lower whereas the baseline cervical dilatation was significantly greater in the misoprostol group. We conclude that oral misoprostol is effective for pre-operative cervical dilatation in non- pregnant women.      

Mitochondrial DNA deletion in human oocytes and embryos

Mitochondrial DNA (mtDNA) deletions are present in both human oocytes and embryos. It has been found that these tissues contain a mtDNA mutation which is present in high amounts in patients with Kearns-Sayre syndrome (KSS) and progressive external ophthalmoplegia. In the present study, the frequency of this KSS deletion was investigated in human oocytes and embryos. Using a nested primer polymerase chain chian reaction (PCR) strategy, the frequency of the KSS deletion in 74 human oocytes and 137 embryos was found to be 32.8 and 8.0% respectively. Using a 'long PCR-short PCR' nested primer strategy, the frequency of the KSS deletion in 181 human oocytes and 104 embryos was found to be 47.0 and 20.2% respectively. There was no statistical correlation between the age of the patients at the time of oocyte retrieval and the presence of the deleted molecules. There was a statistical difference between the presence of the deleted molecules in oocytes versus embryos using either technique (P < 0.0001). The relevance of these findings to the accumulation of low levels of deleted mtDNA in both oocytes and embryos is discussed in this study.