Altered dopamine metabolism and its role in pathogenesis of Parkinson's disease / 生理学报

Parkinson's disease (PD), one of the most frequent neurodegenerative disorders, is characterized by the selective loss of dopaminergic neurons in the substantia nigra (SN). Genetic vulnerability, aging, environmental insults are believed to contribute to the pathogenesis of PD. However, the cellular and molecular mechanism of dopaminergic neurons degeneration remains incompletely understood. Dopamine (DA) metabolism is a cardinal physiological process in dopaminergic neurons, which is closely related to the loss of dopaminergic neurons in the SN. DA metabolism takes part in several pathological processes of PD neurodegeneration, such as iron metabolism disturbance, α-synuclein mis-folding, endoplasmic reticulum stress, protein degradation dysfunction, neuroinflammatory response, etc. In this review, we will describe altered DA metabolism and its contributions to PD pathogenesis.

Clinical observation of closed reduction and compression cannulated screw fixation for the treatment of femoral neck fracture in young and middle-aged patients / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the clinical effect of internal fixation with closed reduction and hollow compression screws for the treatment of femoral neck fracture in young and middle-aged patients.</p><p><b>METHODS</b>From June 2013 to December 2016, 33 young and middle-aged patients with femoral neck fractures were treated with hollow compression screws fixation including 17 males and 16 females with an average age of 38.5 years old ranged from 19 to 59 years old; 20 cases were on the left side and 13 cases on the right side;the time from injury to operation ranged from 2 to 5 days with an average of 3 days. According to Garden classification, 1 case were type I, 11 cases were type II, 18 cases were type III, 3 cases were type IV. During regular follow-up after operation, through the hip joint X-ray, the healing situation of bone and osteonecrosis were observed. The Harris score was used to evaluate the hip function of the final follow-up.</p><p><b>RESULTS</b>The operation time was from 30 to 50 minutes, the blood loss during operation was 20 to 70 ml. All patients were followed up for 8 to 42 months with an average of 24 months. At the final follow-up, the Harris score of hip joint was excellent in 18 cases, good in 10 cases, fair in 2 cases and poor in 3 cases. Among them, the pain scores were 40.61±5.08, function scores were 38.94±6.78, malformation scores were 3.88±0.69, motion range scores were 3.70±0.64 and the total scores were 87.12±11.98. Thirty cases achieved bone healing, the healing time was 4 to 12 months with an average of 7.5 months, 2 patients occurred with nonunion (Garden type IV), 1 patient with femoral head necrosis (Garden type IV). All patients had no postoperative infection, internal fixation loosening, refracture and other complications.</p><p><b>CONCLUSIONS</b>In treating the young and middle-aged patients with femoral neck fracture, closed reduction and hollow compression screw fixation has advantages of simple, stable fixation, less trauma, high rate of fracture healing, osteonecrosis of the femoral head with low risk and satisfactory clinical effect.</p>

Role of MAPK and PKC signaling pathways in the regulation of c-erbB₂ in the primordial follicles onset / 生理学报

Our previous studies showed that the proto-oncogene c-erbB₂ played an important role in primordial follicles growth. The present study was conducted to investigate the role of MAPK and PKC signaling pathways in the primordial follicle onset in neonatal rats, and the relationship between c-erbB₂ and MAPK/PKC signaling pathways. Ovaries collected from 2-day-old Sprague-Dawley rats were cultured in the Waymouth culture system in vitro. Ovaries were transfected with c-erbB₂ siRNA, or treated with PD98059 (50 mumol/L) or Calphostin (0.5 mumol/L) in the culture medium. RT-PCR was performed to measure the expression of c-erbB₂ mRNA, and Western blot analysis was performed to measure the expression of ErbB₂, MAPK and PKC protein after the neonatal rat ovaries were cultured for 8 d. The quantities of every-stage follicles of ovaries cultured for 8 d were obtained in histological section stained with hematoxylin eosin. The results showed that c-erbB₂ siRNA reduced the levels of c-erbB₂ mRNA (P<0.01) and the levels of ErbB₂, MAPK and PKC protein (P<0.01) significantly. But the levels of c-erbB₂ mRNA and ErbB₂ protein exhibited no change (P>0.05) in the ovaries cultured with PD98059 or Calphostin. After the ovaries were transfected with c-erbB₂ siRNA or cultured with PD98059 or Calphostin for 8 d, the quantities of primary follicles and second follicles were lower than those in the control group (P<0.05 or P<0.01), but the quantity of the primordial follicles was higher than that in the control group (P<0.01). These results suggest that proto-oncogene c-erbB₂ promotes the initiation of primordial follicle growth through the MAPK and PKC signal transduction, and c-erbB₂ is possibly the upstream of PKC and MAPK signaling pathway in the regulation of primordial follicle onset.

Trend of bone development of adolescent at 14 years old / 法医学杂志

OBJECTIVE@#To describe characteristic of hand-wrist bone development in adolescents of 14 years old in China, and to estimate trend of bone development of them.@*METHODS@#A total of 109 adolescents of 14 years was selected as subjects (males: 53, females: 56). X-rays examination of their left hand-wrist bone were performed and analyzed. The development characteristics of each position in accordance with Gu's mapping of skeletal age were compared with Gu's results and ours.@*RESULTS@#Compared with Gu's, osteoepiphysis of distal radius, the first metacarpal bone, the fourth proximal phalanx were more advanced in boys, osteoepiphysis of distal radius, the second-fifth metacarpal bones, the first-fifth proximal phalanxs, and the second-fifth middle phalanxs were more advanced in girls.@*CONCLUSION@#The results suggested that a forward trend of 14 years old adolescents bone development currently exists in our country, especially in girls. As an important age of criminal responsibility, this forward trend of development of bones among adolescents currently should be kept in mind when estimating bone age of criminals.