Metastatic embryonal rhabdomyosarcoma of the breast: A case report and literature review

Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.     

微波体模

用水、盐,聚氯乙烯粉和羧甲基纤维钠四种材料配制成一种适用的微波体模(模拟肌肉组织)。该体模的复介电系数在300～2500MHz范围内与实际人体肌肉组织的误差≤5％。这种体模的优点是材料立足国内,价廉,室温下配制,使用方便。本文也给出这种体模的温度特性,稳定性和热学特性,供电磁场生物效应和微波热疗等研究使用。     

4型腺病毒载体的构建和β－半乳糖苷酶基因的表达

以４型腺病毒疫苗株感染Ａ５４９细胞，提取病毒ＤＮＡ，将ＥｃｏＲＩ消化的Ｄ片段（７０．５－８３．０基因图谱单位）克隆入ｐＵＣ１８质粒，得ｐＡｄ４（７０．５－８３）质粒，质粒ｐＡｄ４（７０．５－８３）和ｐＡｄ４Ｃ１－２５经酶切、系列亚克隆、加接头等方法得到大部分和部分缺失Ｅ３区的重组质粒。聚合酶链反应（ＰＣＲ）法获得ｐｏｌｙ（Ａ），构建约８００ｂＰ腺病毒晚期表达盒，在所构建的腺病毒重组质粒Ｅ３缺失区或Ｅ４与ＩＴＲ间插入表达盒，得到可同时表达２个或２个以上外源基因和保留了Ｅ３区编码分子量为１９３００糖蛋白基因的３种Ａｄ４载体。将ｌａｃＺ基因插入载体表达区，与Ｂｅｌｌ消化的Ａｄ４ＤＮＡＡ片段共转染Ａ５４９细胞，ＯＮＰＧ法检测证实所构建的载体和表达盒功能良好。本项工作对于在国内研究口服活疫苗及开展基因治疗均具有重要意义。     

Allosteric effects of mutations in the extracellular S5-P loop on the gating and ion permeation properties of the hERG potassium channel

The hERG channel has an unusually long (39 amino acids) extracellular loop between the transmembrane S5 segment and the pore region that may play a role in channel function. We explored this possibility by mutating two histidine residues in this region (H578 and H587, referred to as H1 and H2) to various residues and examined the resulting changes in channel function. Both positions could tolerate drastic changes in side-chain properties (proline, cysteine, glutamate and lysine), indicating that they are solvent exposed. None of the H1 mutations affected hERG channel function. On the other hand, although replacing H2 with glutamate had little or no effect on hERG properties, putting a proline or lysine at this position disrupted the C-type inactivation process and the pore's K selectivity. There was also a hyperpolarizing shift in the voltage dependence of activation. The phenotype of the H2C mutant was similar to that of H2P or H2K. However, dithiothreitol (DTT, a thiol-reducing agent) treatment converted the H2C phenotype to that of the wild-type channel. These observations suggest that the peptide backbone conformation around position 587 in the extracellular S5-P loop of hERG channel can affect the channel's gating and ion selectivity functions.     

Seroprevalence studies using a recombinant norwalk virus protein enzyme immunoassay

A recombinant Norwalk virus (NV) protein enzyme immunoassay was used to study the age of acquisition of NV IgG in various populations. In London, England, there was little evidence of infection during the first 2 years of life. However, the prevalence of NV IgG rose steadily throughout the period that children attend school, reaching a peak of 70% in the group aged 11–16 years. High levels of maternal antibody were detected in infants aged <3 months. Comparison of the acquisition of antibodies to three strains of human calicivirus in Japanese children in northern Japan indicated that although the majority had experienced infection with strains Japan and UK1 by the age of 12 years, only 22% possessed antibodies to NV. In Australian aborigines NV infection occurs early in life; by the age of 6 years over 90% of children were seropositive. © 1994 Wiley-Liss, Inc.     

Involvement of antioxidant enzymes in multiple-drug resistance in a human T-lymphoblastic leukemia-cell line which over-expresses p-glycoprotein

We have compared the specific activities of Cu/Zn superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in a vinblastine sensitive human T-lymphoblastic cell line (CCRF-CEM) and its multiple drug resistant (MDR) counterpart cell line (CEM/VLB100), which over-expresses P-glycoprotein (PGP). We have found that the specific activity Cu/Zn SOD was consistently 38% increased in CEM/VLB100 cells compared with CCRF-CEM cells. In contrast, the activities of CAT and GSH-Px were similar in the two cell lines. These results suggest that MDR in CEM/VLB100 is a complicated phenotype which not only involves a PGP mechanism, but also a SOD protection mechanism against drug-mediated O2.- cytotoxicity.     

Debrisoquine hydroxylation and sulfamethazine acetylation in a Chinese population

Both debrisoquine hydroxylation and sulfamethazine acetylation phenotypes were studied in the same native Chinese population. Debrisoquine hydroxylation status was determined by HPLC assay of debrisoquine metabolic ratio in urine after a single oral dose of 10 mg debrisoquine. Three poor metabolizers were found in 220 subjects (1.36%). One hundred and one subjects of this population previously debrisoquine phenotyped were also tested for acetylation phenotyping on a separate occasion. Their acetylation status were determined by HPLC assay of "% acetylation" after a single oral dose of 1 g sulfamethazine. Twenty (19.8%) slow acetylators were found. There were no significant association between the 2 metabolic pathways.