[Clinicopathological characteristics of gangliogliomas with anaplastic morphology].

Objective: To investigate the clinical, radiological, and pathological features of anaplastic gangliogliomas (AGGs) and to determine whether these tumors represent a distinct entity. Methods: Consecutive 667 cases of ganglioglioma (GG) diagnosed at the Xuanwu Hospital, Capital Medical University, Beijing, China between January 2015 and July 2023 were screened. Among these cases, 9 pathologically confirmed AGG cases were identified. Their clinical, radiological, treatment, and outcome data were analyzed retrospectively. Most of the tumor samples were subject to next-generation sequencing, while a subset of them were subject to DNA methylation profiling. Results: Among the 9 patients, there were five males and four females, with a median age of 8 years. Epileptic seizures (5/9) were the most frequently presented symptom. Radiological examinations showed three types of radiological manifestations: four cases showed abnormal MRI signals with no significant mass effects and mild enhancement; two cases demonstrated a mixed solid-cystic density lesion with peritumoral edema, which showed significant heterogeneous enhancement and obvious mass effects, and one case displayed cystic cavity formation with nodules on MRI, which showed evident enhancements. All cases exhibited mutations that were predicted to activate the MAP kinase signaling pathway, including seven with BRAF p.V600E mutation and two with NF1 mutation. Five AGGs with mutations involving the MAP kinase signaling pathway also had concurrent mutations, including three with CDKN2A homozygous deletion, one with a TERT promoter mutation, one with a H3F3A mutation, and one with a PTEN mutation. Conclusions: AGG exhibits a distinct spectrum of pathology, genetic mutations and clinical behaviors, differing from GG. Given these characteristics suggest that AGG may be a distinct tumor type, further expansion of the case series is needed. Therefore, a comprehensive integration of clinical, histological, and molecular analyses is required to correctly diagnose AGG. It will also help guide treatments and prognostication.

[Preparation of novel magnetic dextran affinity adsorbents and their application to purify urokinase].

The reverse phase suspension and embedment technique were adopted to prepare magnetic dextran microsphere (MDMS). The dispersion medium was mixture of some organic solvents. Span-80 was used as stabilizer. The aqueous dextran with magnetic fluid was suspended in dispersion medium with epichlorohydrin as cross-linking reagent. The mixture was stirred for 30 minutes at room temperature and then heated at 70 degrees C for 4 hours, MDMS was thus obtained. MDMS was activated by epichlorohydrin on which 6-aminohexanoic acid, glycine or ethylene diamine was bonded as spacers. Then it was coupled with p-aminobenzamide, L-arginine methyl ester or guanidohexanoic acid and five magnetic affinity adsorbents were prepared. The MDMS was polydisperse particles with the size of 50-300 meshes and the content of Fe3O4 was about 6.2 per cent in the MDMS. Influence of some parameters such as viscosity and density of organic phase, the volume ratio of organic and aqueous phase, the quantity of surfactant and stirring speed on preparing MDMS was studied. Magnetic affinity adsorbents were used to purify crude urokinase in a bath mode and the effect of coupling reagents and ligands on results of purification was discussed. The bioactivity recovery was 40.0 to 60.7 per cent, the purification-fold was between 14.9 and 32.8, and the adsorptive capacity varies from 89 mg to 121 mg per milliliter of adsorbent.

[Simultaneous purification and renaturation of recombinant human interferon-alpha expreessed by E. coli by high-performance hydrophobic interaction chromatography].

One-step simultaneous purification and renaturation of interferon-alpha from the inclusion body of E. coli expreessed by high-performance hydrophobic interaction chromatography(HPHIC) are presented. The inclusion body was dissolved by 8 mol/L guanidine hydrochloride. The sample lysis was centrifuged and the solution was renaturated by three different methods, i.e. hydrophobic interaction chromatography, dilution and dialysis. The total activity yield renaturation by hydrophobic interaction chromatography was 2 times and 2.6 times as much as that by dilution and by dialysis. The purity of the target product was 95% according to high-performance size exclusion chromatography and the specific activity was 1.8 x 10(8) IU/mg. The method developed is simpler and more efficient than others.

[Purification of vancomycin by using magnetic affinity technique].

A new kind of magnetic affinity microspheres (MAMS), whose ligand is D-Ala-D-Ala, was prepared using agarose as matrix. By using this new MAMS vancomycin was purified directly from crude fermentation liquor with only one step. The purity and the mass recovery of vancomycin measured by reverse-phase HPLC were 97% and 87%, respectively. The characteristic of this method was simpler, faster, cheaper and more effective than that of currently used ones.

[Study on the packings of affinity chromatography for the separation of urokinase].

Two kinds of affinity chromatographic packings for the separation of urokinase were synthesized by coupling of p-amino benzamidine (p-ABZ) to commercially available sepharose and polyepoxypropyl methacrylate (PEPMA). Then they were applied for separating crude urokinase. It was found that the average recovery of bioactivity on sepharose was higher than that on PEPMA, resulting in 108.3% and 43.4% respectively. The high rigidity of PEPMA permits fast flow of protein solutions and operation by higher-pressure affinity chromatography. The average purification times were 36.9 folds for PEPMA column and nine-folds for Sepharose column. The purification of crude urokinase described in this paper demonstrates that PEPMA column is effective for purifying biological products in a large scale.

[Purification of follicle-stimulating hormone by radial-flow chromatography].

By comparing the purification results of radial-flow chromatography with conventional chromatography, a new purification process of follicle-stimulating hormone (FSH) from crude sample of human menopausal gonadotrophin has been developed. The results showed that the specific activity, activity recovery, and purification factor of FSH purified by radial-flow chromatography were higher than those by conventional chromatography in large scale. The specific activity of FSH purified was 180 IU/mg protein, activity recovery 56%, purification factor 150. The purified product meets the quality requirement of the Standard of Chinese Pharmacopoeia.