Objective To investigate the expression changes of the protein tyrosine phosphatase receptor T (PTPRT) in temporal lobe epileptic foci in the experimental animals and epileptic patients and the relationship between PTPRT and epileptogenesis.Methods After getting the epilepsy lobe tissue from the experimental and control groups,immunohistochemistry,immunofluorescence and Western blot analysis were used to assess the expression of PTPRT and its changes.Results In the temporal lobe tissue of intractable patients and control group,PTPRT was mainly expressed in the neurons.PTPRT was significantly increased in patients with intractable epilepsy (0.277 ± 0.048) than that in the control group(0.171 ±0.025 ; t =9.586,P ＜ 0.05).PTPRT was mainly expressed in the neurons in the temporal lobe brain tissue of the rats in the control group and experimental group.Compared with control group,the expression of PTPRT in the temporal lobe tissue was increased within 24 h post-seizure,and decreased 1 and 2 weeks post-seizure,then it was increased 1 and 2 months post-seizure (A ratio:control 0.443 ± 0.039,6 h 0.840±0.032,24 h 1.113 ±0.064,7 d 0.564 ±0.039,14 d 0.570 ±0.029,30 d 0.899 ±0.034,60 d 1.011 ± 0.074,F =256.427,P ＜ 0.05).Conclusions Through researches into the expression and function of PTPRT in the temporal lobe brain tissue of patients with intractable epilepsy and animal models,we presume that the PTPRT plays a role in the synapses reorganization and mossy fiber sprouting,and participates in the reconstruction of the neural network which leads to the intractable epilepsy.

OBJECTIVETo type and group the Shiga-toxin producing Escherichia coli O157:H7 strains isolated recent years in China to understand the epidemiological features caused by the pathogen.

METHODSPulsed field gel electrophoresis of large restriction fragments of bacterial chromosomal DNA was used.

RESULTSThe 51 isolates of E. coli O157:H7 collected in recent years in China could be divided into 8 Pulsed Field Gel Electrophoresis (PFGE) types based on the size and number of restriction fragments and patterns, that were digested by XbaI. Strains isolated from Ningxia province showed only two types- PFGE1 and PFGE2. Strains isolated in Xuzhou of Jiangsu province had 6 PFGE types. Isolates identified between 1986 - 1988 belonged to PFGE7. Strains isolated from patients in 1999 - 2000 were PFGE5 and PFGE3. Strains isolated from stool samples of domestic animal, food and vegetable were PFGE3 - 6, of which the predominant type was PFGE5. All of the 5 strains isolated from patients with diarrhea and hemolytic uremic syndrome (HUS) belonged to PFGE type 5, which was the dominant type of the isolates from stool samples of domestic animal and samples of food and vegetable contaminated.

CONCLUSIONData suggested that the cluster patients with diarrhea and HUS might have been related to the pathogens from domestic animas and contaminated food or vegetables. The distribution of PFGE types also varied in different provinces of China.

Electrophoresis, Gel, Pulsed-Field ; Escherichia coli O157 ; classification ; genetics ; pathogenicity ; Genotype ; Humans ; Shiga Toxin ; biosynthesis

Objective:To report the clinical and genetic characteristics of autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) induced by a new homozygous mutation in the SACS gene, and to improve the clinicians′ recognition of the disease. Methods:Detailed nervous system physical examination was performed on the patient and his parents from a consanguineous family admitted to the Genetics and Metabolism Clinic of the Department of Neurology, the First Affiliated Hospital of Kunming Medical University in March 2022. The peripheral blood DNA of the patient and his parents was extracted, and whole exon sequencing (WES) was performed on the patient and his parents using second-generation sequencing technology. The mutation sites were verified by Sanger sequencing, and the mutation sites were analyzed by software.Results:The 18-year-old Han ethnic male patient developed a progressive stiffness of his bilateral lower limbs and gait unsteadiness since the age of 3. He had pyramidal tract sign in his bilateral lower limbs, cerebellar ataxia, pes cavus and hammer toes. Brain magnetic resonance imaging (MRI) showed symmetrical low signal of bilateral pons, cerebellar atrophy and thinning of corpus callosum in T 2WI and T 2 fluid attenuated inversion recovery (FLAIR) sequences. Neuroelectrophysiological examination showed sensory motor peripheral neuropathy. Ophthalmic examination revealed concomitant exotropia and ametropia in both eyes. WES revealed a homozygous variant of c.6958T>C (p.Tyr2320His) in exon 10 of the SACS gene of the patient, and his parents were heterozygous variant carriers confirmed by Sanger sequencing. The variant was classified as possibly pathogenic (PM1+PM2+PP3+PP4) according to the American Society for Medical Genetics and Genomics. The patient was clearly diagnosed as ARSACS caused by homozygous mutation of c.6958T>C in the SACS gene. Conclusions:A novel pathogenic variant (c.6958T>C) in the SACS gene identified in this study leads to the manifestation of ARSACS. The primary clinical manifestations include cerebellar ataxia, pyramidal tract signs, and sensorimotor peripheral neuropathy. Head MRI examination of T 2WI and T 2FLAIR sequences with symmetrical low signal on both sides of the pons helps to narrow down the scope of differential diagnosis.