Feng Sw

Baculovirus-transduced mouse amniotic fluid-derived stem cells maintain differentiation potential.

Amniotic fluid-derived stem cells have attracted considerable attention in the field of regenerative medicine. Approach of genetic modification probably enhances their regenerative potential. In this work, we wanted to determine whether baculovirus as a new gene vector could efficiently and safely transduce mouse amniotic fluid-derived stem cells (mAFSs). Cells were isolated from mouse amniotic fluid and cultured in vitro. These cells were analyzed by examining phenotypes and differentiation potential. They were further transduced with baculovirus. Baculovirus-transduced mAFSs were induced to differentiate into adipogenic, osteogenic, myogenic, and neurogenic lineages. Mouse amniotic fluid-derived stem cells were successfully isolated and cultured in vitro. They were positive for CD29 and Sca-1, but negative for CD34, CD45, or CD11b. Furthermore, they could differentiate into adipocytes, osteocytes, myocytes, and neurocytes in vitro. Baculovirus could efficiently transduced mAFSs. More importantly, baculovirus-transduced mAFSs retained differentiation potential. Thus, baculovirus vector effective and safe transduction is an attractive promise for genetic modification of mAFSs. Baculovirus genetically modified mAFSs will probably be more suitable as vehicles for regenerative medicine.

Genotypic and clinical features of spinal muscular atrophy type 3

OBJECTIVE To explore the genotypic and clinical features and laboratory examinations of spinal muscular atrophy type 3 (SMA III). METHODS Results of genetic testing and laboratory exams of 18 SMA III patients were collected and analyzed. RESULTS The average age of onset of patients was 6.1 years, with the course of disease lasting from 13 months to 28 years. All patients became symptomatic with lower extremity muscle weakness. The symptoms gradually aggregated, with proximal lower limb muscle becoming atrophic and proximal upper limb muscle becoming weak. Genetic testing indicated that all subjects possessed homozygous deletions of SMN1 gene. Electromyography (EMG) of 15 subjects indicated neurogenic damage. Whilst younger patients had normal level of creatine kinase (CK), elder patients had higher level of CK, though no linear correlation was found. CONCLUSION Full understanding of Clinical, especially the growth features of SMA III, in combination with genetic testing, can facilitate diagnosis and early intervention of the disease.

Characterization of muscular involvement in patients with Duchenne muscular dystrophy by magnetic resonance imaging

OBJECTIVE To study the order and degree of muscular affection in patients with Duchenne muscular dystrophy (DMD) during the course of disease. METHODS Multiplex ligation dependent probe amplification (MLPA) was used to detect potential mutation of dystrophin gene. Magnetic resonance imaging (MRI) was used to scan the anteromedial aspect of thigh muscles. RESULTS All of the 6 patients were found to have deletion or duplication mutations. The order of affection has been gluteus maximus, adductor magnus, quadriceps femoris, rectus femoris and biceps muscle of the thigh, while semimembranous muscle, semitendinosus, sartorius muscle and musculus gracilis are selectively affected and in a decreasing order. CONCLUSION MRI can reflect the order, extent and degree of skeletal muscle involvement in patients with DMD, and can reflect pathological changes of damaged skeletal muscle at each stage, which may provide an important means for patient examination and diagnosis. No apparent correlation between the severity of disease and the nature of mutations was noted.

Study on Duchenne muscular dystrophy gene mutation and prenatal diagnosis

OBJECTIVE To explore the characteristics of DNA mutations underlying Duchenne muscular dystrophy and provide prenatal diagnosis. METHODS Multiplex ligation-dependent probe amplification (MLPA) and denaturing high performance liquid chromatography (DHPLC) were applied for analyzing DMD gene mutations in 388 unrelated Chinese patients and 53 fetuses. RESULTS Respectively, 230 and 43 subjects were found to harbor a deletion (59.28%) or duplication (11.08%). Two deletion hotspots were identified, which have located at exons 45-54 and exons 3-19. Duplications were mainly detected at exons 2-43. Point mutations were identified in 29.64% of patients. Fifty three fetuses were prenatal diagnosed, among which 18 were identified as patients. CONCLUSION Frequencies of DMD gene deletions and duplications in China are similar to global data. Prenatal diagnosis can help to reduce births of DMD patients.