Multigene manipulation of photosynthetic carbon metabolism enhances the photosynthetic capacity and biomass yield of cucumber under low-CO2 environment.

Solar greenhouses are important in the vegetable production and widely used for the counter-season production in the world. However, the CO2 consumed by crops for photosynthesis after sunrise is not supplemented and becomes chronically deficient due to the airtight structure of solar greenhouses. Vegetable crops cannot effectively utilize light resources under low-CO2 environment, and this incapability results in reduced photosynthetic efficiency and crop yield. We used cucumber as a model plant and generated several sets of transgenic cucumber plants overexpressing individual genes, including ß-carbonic anhydrase 1 (CsßCA1), ß-carbonic anhydrase 4 (CsßCA4), and sedoheptulose-1,7-bisphosphatase (CsSBP); fructose-1,6-bisphosphate aldolase (CsFBA), and CsßCA1 co-expressing plants; CsßCA4, CsSBP, and CsFBA co-expressing plants (14SF). The results showed that the overexpression of CsßCA1, CsßCA4, and 14SF exhibited higher photosynthetic and biomass yield in transgenic cucumber plants under low-CO2 environment. Further enhancements in photosynthesis and biomass yield were observed in 14SF transgenic plants under low-CO2 environment. The net photosynthesis biomass yield and photosynthetic rate increased by 49% and 79% compared with those of the WT. However, the transgenic cucumbers of overexpressing CsFBA and CsSBP showed insignificant differences in photosynthesis and biomass yield compared with the WT under low-CO2.environment. Photosynthesis, fluorescence parameters, and enzymatic measurements indicated that CsßCA1, CsßCA4, CsSBP, and CsFBA had cumulative effects in photosynthetic carbon assimilation under low-CO2 environment. Co-expression of this four genes (CsßCA1, CsßCA4, CsSBP, and CsFBA) can increase the carboxylation activity of RuBisCO and promote the regeneration of RuBP. As a result, the 14SF transgenic plants showed a higher net photosynthetic rate and biomass yield even under low-CO2environment.These findings demonstrate the possibility of cultivating crops with high photosynthetic efficiency by manipulating genes involved in the photosynthetic carbon assimilation metabolic pathway.

Old unreduced obturator dislocation of the hip: A case report.

BACKGROUND: Obturator dislocation is a rare type of hip dislocation, accounting for about 2%-5% of all hip dislocations. The occurrence of old unreduced obturator dislocation is even more infrequent, with only 17 cases reported in nine studies, most of which were from the 1950s to 1980s in developing countries. CASE SUMMARY: A 38-year-old woman from Hunan Province, China presented with stiffness of the left hip in abduction, flexion, and external rotation after falling from a 2-meter-tall tree onto her left knee 1.5 mo prior. Pelvic radiograph and computed tomography revealed obturator dislocation of the left hip accompanied by impaction fracture at the superolateral aspect of the left femoral head without associated acetabulum fracture. Open reduction was performed, resulting in restoration of the concentric alignment of the left hip. After surgery, 6-wk skin traction was applied and the patient was kept in bed for an additional 2 wk. At 3 mo after surgery, the patient reported experiencing some pain, which did not affect the function of the affected limb, and some movement restriction but no abduction deformity or claudication was present. An X-ray showed that the left hip was homocentric, and there was no sign of posttraumatic arthritis or avascular necrosis. CONCLUSION: Open reduction may be an effective treatment strategy for the rare condition of old unreduced obturator dislocation with short neglect time.

Modified pararectus approach for treatment of atypical acetabular anterior wall fracture: A case report.

BACKGROUND: Acetabular anterior wall fracture with preservation of the pelvic brim is extremely rare. It is different from anterior wall fracture classified by Judet and Letournel. Few studies have reported cases treated by open reduction and internal fixation via the Smith-Petersen or iliofemoral approach. CASE SUMMARY: We report a 48-year-old Chinese woman who had difficulty moving her right hip from abduction and external rotation after falling from 3 m. Pelvic radiograph and three-dimensional reconstruction of computed tomography revealed acetabular anterior wall fractures combined with fractures of the anterior inferior iliac spine and the iliac wing but not involving the pelvic brim. First, the patient underwent interim management by closed reduction of the hip dislocation and skin traction for 6 d. Then, we used a modified pararectus approach for treatment to fix the acetabular fractures with a reconstruction plate and nonlocking T-shape plate. At the 9-mo follow-up, the patient could walk painlessly without necrosis of the femoral head or heterotopic ossification, and the X-rays and computed tomography scan reconstructions showed good bone union. CONCLUSION: The modified pararectus approach described here can facilitate exposure, reduction, and osteosynthesis for atypical acetabular fracture with less invasiveness.

The Sp1/FOXC1/HOTTIP/LATS2/YAP/ß-catenin cascade promotes malignant and metastatic progression of osteosarcoma.

The prognosis for osteosarcoma (OS) is dismal due to the aggressive tumor growth and high incidence of metastasis. The long noncoding RNA human homeobox A transcript at the distal tip (HOTTIP) and the transcription factor forkhead box C1 (FOXC1) present oncogenic activities in OS. Here, we aimed at gaining insights into the underlying mechanisms and their crosstalk. The expression of FOXC1 and HOTTIP in OS tissues or cell lines was examined by real-time PCR (RT-PCR) and western blot. The in vitro effects of FOXC1 or HOTTIP on cell viability, proliferation, migration, invasion, and expression of target genes were examined using MTT, colony-forming assay, wound-healing, Transwell invasion, and western blot, respectively; the in vivo effects were examined using xenograft and experimental metastasis models. Molecular control of HOTTIP on large tumor suppressor 2 (LATS2) or transactivation of FOXC1 or Sp1 on HOTTIP was assessed by combining RNA immunoprecipitation, qRT-PCR, western blot, ChIP, and luciferase assay. Both FOXC1 and HOTTIP were potently up-regulated in OS tissues and cell lines. FOXC1 and HOTTIP essentially maintained viability, proliferation, migration, and invasion of OS cells in vitro and contributed to xenograft growth or lung metastasis in vivo. Mechanistically, HOTTIP recruited enhancer of zeste homolog 2 (EZH2) and lysine-specific demethylase 1 (LSD1) to silence LATS2 and thus activated YAP/ß-catenin signaling. Upstream, Sp1 activated FOXC1 and they both directly transactivated HOTTIP. In summary, we showed that the Sp1/FOXC1/HOTTIP/LATS2/YAP/ß-catenin cascade presented oncogenic activities in OS cells. Targeting FOXC1 or HOTTIP may therefore prove beneficial for OS treatment.

LncRNA-MALAT1 promotes osteogenic differentiation through regulating ATF4 by sponging miR-214: Implication of steroid-induced avascular necrosis of the femoral head.

OBJECTIVE: To study roles oflncRNA-MALAT1 and miR-214 in steroid-induced avascular necrosis of the femoral head (SANFH). METHODS: MALAT1, miR-214 andosteogenic-relatedgenes(Runx2, ALP, andOCN)expressions were determined in SANFH tissue samples and human bone marrow stromal cells (BMSC) by RT-qPCR. BMSCs were verifiedbyflowcytometry. The ATF4 level was determined by western blotting and RT-qPCR. Osteogenesis inducedbyosteogenic medium (OM) in BMSCs and dexamethasone (DEX) was used to inhibit osteogenesis. The alkaline phosphatase (ALP) activity was measured and ALP staining and alizarin red staining were conducted for evaluation of osteogenic differentiation. MTT assay was used for cell proliferation. The dual luciferase reporter assay was used to confirm binding between MALAT1 and miR-214, as well as miR-214 and ATF4. RESULTS: MALAT1 was down-regulated and miR-214 was up-regulated in SANFH tissues. DEX inhibited osteogenic differentiation of BMSC in a dose-dependent manner, leading to decreased MALAT1, increased miR-214, as well as reduced ALP activity and decreased expression of RUNX2, ALP and OCN. Either overexpression of MALAT1 or inhibition of miR-214 improved DEX-induced inhibition of BMSC osteogenic differentiation. The overexpression of miR-214 reversed the effects by MALAT1. MALAT1 directly sponged miR-214 and miR-214 directly targeted ATF4. CONCLUSION: MALAT1 was down-regulated, while miR-214 was elevated in SANFH tissues. MALAT1 promoted osteogenesis differentiation by sponging miR-214 to upregulate ATF4.