Diterpenes, an important class of natural compounds, are widely distributed in nature. As the valuable diterpenoids continue to be found, diterpene synthase in the course of diterpene synthesis get as much attention as possible. The multiformity of end-product-diterpenoids were also due to the diversity of diterpene synthase. This paper focuses on the advances in recent biosynthesis pathway of diterpene and types, cloning, catalytic mechanism, synthetic biology application.
Alkyl and Aryl Transferases ; metabolism ; Biosynthetic Pathways ; Diterpenes ; metabolism ; Isomerases ; metabolism ; Phosphorus-Oxygen Lyases ; metabolism ; Plant Proteins ; metabolism

Objective To observe the improving effect in joint function of moderate skeletal fluorosis treated by traditional Chinese medication(main ingredient was Strychnine).MethodsFrom December 2007 to July 2009,120 moderate skeletal fluorosis patients met the inclusion criteria were divided into the treatment group(60 cases)and the control group(60 cases)in the skeletal fluorosis hospital of Xinzhou,the treatment group was given basic treatment and traditional Chinese medication,the control group wa8 given basic treatment and placebo.The treatment lasted 12 weeks,follow up 24 weeks.Before treatment,after treatment 4 weeks,8 weeks,12 weeks,36 weeks,a third party evaluate comprehensive function of both upper and lower limb and joint dysfunction.Results The main effect of both drugs was statistically significance in the scores of the upper forearm in the finger by touching the posterior contralateral ear, upper arm touched by the finger back in the opposite corner subscapularis function, lower limb function and single-joint dysfunction(F values were 4.08,14.32,35.81,13.02, all P<0.05), the main effect of time also was significant (F values were 82.63,72.82,277.33,328.16, all P<0.05),①the upper forearm in the finger by touching the posterior contralateral ear functions:At the time of 8,12 weeks,scores of the treatment group were lower than those of before treatment and control group (all P<0.05);At the time of 36 weeks,scores of the treatment group were lower than that 12 weeks(all P<0.05);At the time of 8,12,36 weeks, scores of the control group were lower than those of before treatment(all P < 0.05);②upper arm function, namely fingers touching the opposite corner subscapularis:At the time of 4,8,12 weeks, scores of the treatment group were lower than those of before treatment(all P<0.05); At the time of 36 weeks, scores of the treatment group were lower than that 12 weeks(all P<0.05); At the time of 8,12,36 weeks, scores of the treatment group were lower than those of the control group (all P<0.05);③Lower extremity functions: At the time of 8,12 weeks,scores of the treatment group were lower than those of before treatment and control group (all P<0.05);At the time of 36 weeks, scores of the treatment group were lower than that 12 weeks(all P<0.05) ; At the time of 8,12,36 weeks, scores of the control group were lower than those of before treatment (all P<0.05);④single joint functions:At the time of 4,8,12 weeks,scores of the treatment group were lower than those of before treatment(all P<0.05); At the time of 36 weeks,scores of the treatment group were lower than that 12 weeks(all P<0.05) ; At the time of 8,12,36 weeks, scores of the control group were lower than those of before treatment(all P<0.05);At the time of 4,8,12,36 weeks, scores of the treatment group were lower than those of control group(all P<0.05);⑤At the end of treatment and follow-up,the improvement rate in joint functions in the treatment group were 88.33% (53/60),93.33% (56/60); the control group were 28.07%(16/57),40.35%(23/57), (Fisher test, P<0.01,X2=56.21, P<0.01). ConclusionTraditional Chinese medication(its main ingredient is Strychnine), an effective drug for improving joint dysfunction in patients suffering from moderate skeletal fluorosis, is simple and effective.

Objective To investigate and control the outbreak of infection caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) in a gastroenterology intensive care unit (ICU), so as to provide reference for the prevention and control of clinical multidrug-resistant organisms (MDROs).Methods Epidemiological investigation was conducted on 3 patients with CRKP infection in a gastroenterology ICU on January 21-31, 2018, specimens were collected with environmental biology monitoring method, CRKP in environment was searched, homology between patients and environmental isolates were analyzed by pulsed-field gel electrophoresis (PFGE).Results Three patients were all isolated CRKP from sputum and blood specimens, all were male, with adjacent beds in the same ward, and treated by the same doctor.The number of isolated CRKP and infection rate in January 2018 were higher than those in other months, infection rate was significantly different (χ2=13.67, P＜0.01).A total of 102 environmental specimens were collected, including air and surface of objects, only 1 of which (nurse's uniform) was isolated 1 strain of KP.PFGE typing of KP isolated from patients and environment showed that there were two genotypes A and B, KP isolated from uniform of a nurse, hydrops abdominis and blood specimen of patient at bed 07, blood specimen of patient at bed 08, as well as sputum and blood specimen of patient at bed 09 were all type A, KP isolated from sputum specimen of patient at bed 07 was type B, KP isolated from hydrops abdominis in patient at bed 09 was not be typed.After comprehensive intervention, CRKP was not no longer isolated from 3 patients, and there was no new case in the ward.Conclusion Imperfect implementation of prevention and control measures for MDROs by health care workers may be an important cause for the spread of CRKP.

OBJECTIVETo investigate the role of Twist in regulating the proliferation, migration, and invasion of osteosarcoma cells with different levels of malignancy.

METHODSThe baseline expressions of Twist in 3 different osteosarcoma cell lines (143B, MG63 and TE85) were detected using real-time PCR and Western blotting. The cells were infected with the recombinant adenoviruses Ad-Twist or Ad-siTwist for Twist overexpression or knockdown, respectively, and the cell growth curves were drawn to assess the cell proliferation. The migration abilities and invasiveness of the cells were evaluated using wound healing assay and Transwell assay. Luc-labeled 143B cells infected with Ad-Twist or Ad-siTwist were intrathecally injected to establish nude mouse models bearing osteosarcoma xenografts, in which the tumor formation was monitored using living body imaging technique.

RESULTSThe baseline expressions of Twist in the 3 osteosarcoma cells were significantly higher than that in C3H10 cells (P<0.05). Twist expression was the highest in 143B cells followed by MG63 cells, and was the lowest in TE85 cells, indicating its positive correlation with the level of malignancy of the osteosarcoma cells. Ad-Twist or Ad-siTwist infection efficiently enhanced or lowered Twist expressions at both mRNA and protein levels in osteosarcoma cells (P<0.05). Twist overexpression resulted in enhanced proliferation, migration and invasion abilities of osteosarcoma cells, and Twist knockdown obviously inhibited the cell proliferation, migration and invasion. In nude mice, 143B cells with Twist overexpression showed accelerated tumor formation compared with the control cells, while Twist knockdown significantly inhibited the tumor formation ability of the cells.

CONCLUSIONTwist overexpression can promote the proliferation, migration, invasion and tumorigenicity of osteosarcoma cells.

OBJECTIVETo analyze the risk factors of hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation for beta-thalassemia in children.

METHODSThe clinical records of 30 children with beta-thalassemia undergoing allogeneic hematopoietic stem cell transplantation between December, 2008 and November, 2009 were analyzed.

RESULTSHemorrhagic cystitis occurred in 8 of the 33 patients with an incidence of 24.24%, including 1 with grade I, 6 with grade II and 1 with grade III hemorrhagic cystitis. The median time of hemorrhagic cystitis onset was 22.9 days (range 6-35 days) and the median duration was 11.9 days(range 3-27 days). Univariate analysis indicated that the different types of transplantation and acute graft-versus-host disease affect the occurrence of hemorrhagic cystitis. The children with Allo-PBSCT had higher incidence than those receiving Allo-PBSCT+Allo-UBT and Allo-BMT (P<0.05). The children at an age >or=6 years had obviously higher incidence of hemorrhagic cystitis than those at younger ages.

CONCLUSIONAge is the major factor that affects the occurrence of hemorrhagic cystitis in children undergoing allogeneic hematopoietic stem cell transplantation for beta-thalassemia.

Age Factors ; Child ; China ; epidemiology ; Cystitis ; epidemiology ; etiology ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Incidence ; Risk Factors ; Transplantation, Homologous ; beta-Thalassemia ; therapy

OBJECTIVETo investigate the possible mechanisms of miR-21-mediated regulation of proliferation and activation of hepatic oval cells.

METHODSThe 2-acetamidofluorene/partial hepatectomy (2-AAF/PH) method was applied to generate hepatic oval cell activation model in male Sprague-Dawley rats; after the 7 days of 2-AAF/PH or PH alone (control), the rats were sacrificed at 0 h, 6 h, 12 h, 24 h, 72 h and 168 h. Expression of miR-21 was detected by real-time PCR and differences between groups were evaluated using the two-sample t-test. Differential transcription of miR-21 target genes was assessed bioinformatically, and with western blotting to detect changes in protein expression of the target gene.

RESULTSThe rat hepatic oval cell activation model was successfully established.The 2-AAF/PH rats showed miR-21 expression beginning to increase at 12 h, peaking at 24 h, and decreasing thereafter until an increase at 168 h.For the control group, the miR-21 expression began to increase at 6 h, until 24 h when expression began steadily declining to reach the original level.Compared to the control group, the experimental group showed expression of miR-21 that was significantly less at 6 h (P=0.039, t =3.029) and significantly more at 24 h and 168 h (P=0.026, t =-3.433 and P=0.007, t =-5.105). Among the predicted target genes of miR-21 were WW domain containing E3 ubiquitin protein ligase 1 (WWD), Smad family member 7 (Smad7), and polybromo-1 (Pbrm1).Smad7 protein expression began to decrease at 6 h in the control group, until reaching its minimum at 24 h when it increased; in the experimental group, SMAD7 expression increased at 6 h, then began to decrease with the minimum detected at 168 hour.In the control group, the Smad7 mRNA expression decreased slightly at 6 h, then began to increase, reaching its peak at 24 h when the expression fell to the original level. In the experimental group, the Smad7 mRNA expression began to increase at 6 h and reached its peak at 24 h when it decreased; the expression was little more than its original level at 168 h.Smad7 protein expression was negatively correlated with miR-21, and Smad7 mRNA expression was positively correlated with miR-21 but negatively correlated with Smad7 protein expression.

CONCLUSIONmiR-21 may play a vital role in the activation and proliferation of hepatic oval cells.As a target gene of miR-21, Smad7 might be involved in the process.

2-Acetylaminofluorene ; Animals ; Cell Proliferation ; Hepatectomy ; Hepatocytes ; cytology ; Liver ; cytology ; Male ; MicroRNAs ; genetics ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction

OBJECTIVETo establish a long-term culture system for mouse spermatogonial stem cells (SSCs) and to discuss the key factor that supports mouse SSC self-renewal and proliferation.

METHODSTestis cells from 4-6 days postpartum male transgenic BALB/c mce were collected by a modified two-step enzymatic digestion method and plated on 0. 2% elatin-coated tissue culture plates. The germ cells were enriched by differential adherence selections after respectively incubated for 1, 5 and 24 h and then plated on the mitomycin C-inactivated mouse embryonic fibroblast (MEF) feeder layer. The basal culture medium was StemPro-34 SFM supplemented with other 15 nutrient factors. The 20 ng/ml Glial cell line-derived neurotrophic factor (GDNF), 10 ng/ml basic fibroblast growth factor (bFGF) and 200 ng/ml GDNF-family receptor alpha 1 (GFRalpha1) were added to the serum-free medium to promote SSC proliferation. Several important surface markers and special genes were examined by immunocytochemical staining and RT-PCR analysis.

RESULTSAfter 3-4 days culture on the MEF feeder, SSCs proliferated continuously and formed typical colonies. SSCs from the BALB/c mice could be cultured in a steady state for 3 months. Immunocytochemical staining showed that Oct4 was specifically expressed in the cultured SSC nucleus and GFRalpha1 strongly expressed on the surface of the membrane. RT-PCR confirmed that the cultured SSCs expressed Oct-4, GFRalpha1, Sox2 and several other special genes resembling undifferentiated spermatogonia.

CONCLUSIONSSCs from BALB/c mice could be cultured in the improved culture system for 3 months. This culture system could help further understand the regulating mechanism of SSCs and might provide an opportunity for the treatment of male infertility by SSC transplantation.

Animals ; Cell Culture Techniques ; methods ; Male ; Mice ; Mice, Inbred BALB C ; Spermatogonia ; cytology ; Stem Cells ; cytology

OBJECTIVETo investigate the roles of the residential environment and eating habits in the pathogenesis of bronchial asthma in school children.

METHODSOne hundred and twenty-nine children between 6-12 years who were diagnosed with asthma were enrolled. Two hundred and fifty-eight healthy age- and gender-matched children were used as the control group. A questionaire which included 23 factors related to respiratory tract anaphylactic diseases such as residential environment and eating habits were completed by the children's parents.

RESULTSLogistic regression analysis showed that 6 variances out of 16 agents of the residential environment, the experience of raising pets, the type of floor, the type of pillow, the type of quilts, the heating equipments and the house area, were entered into the regression equation; none of the 7 variances of eating inhabits was entered into it.

CONCLUSIONSThe residential environment plays an impotent role in the pathogenesis of bronchial asthma in children. The incidence of bronchial asthma in children can be reduced by the improvement of the residential environment.

Asthma ; etiology ; Case-Control Studies ; Child ; Female ; Humans ; Logistic Models ; Male ; Risk Factors

OBJECTIVE: To explore the clinical effect of acupoint puncture combined with Ilizarov technique in the treatment of knee osteoarthritis in the elderly. METHODS: From March 2015 to February 2016, 76 patients with primary knee osteoarthritis were treated with tibial osteotomy acupoint puncture grouop and Ilizarov technique anatomical puncture group, including 24 males and 52 females, aged 56 to 75 years old with an average of 61.4 years old, and a course of 3 to 17 years with an average of 5.2 years. Among them, 38 cases were treated with external fixation of acupoint puncture needle and 38 cases were treated with external fixation of anatomical puncture needle. Preoperative full-length X-ray of both lower limbs showed tibial varus deformity, narrowing of medial knee joint space and enlargement of lateral knee joint space. The force line of the affected knee and lower limb was moved inward by body surface measurement, and the KSS knee function score was decreased. Symptoms included medial knee pain, flexion and extension, and conservative treatment for more than 2 years. RESULTS: The lower limb force lines of both groups were corrected and the osteotomy ends healed well. No nonunion of osteotomy, inadequate correction of lower limbs or recurrence of deformity were found. Seventy-five patients were followed up for 3, 6, 12 and 24 months after operation. There was no significant difference in knee joint mobility between the two groups before operation and on 6, 12, 24 months after operation(=1.346, >0.05). There were significant difference in KSS pain and total score between the two groups at 3 months after operation, acupoint puncture group was better than anatomical puncture group(<0.05); there was no significant difference in KSS score at 12 months after operation(>0.05). CONCLUSIONS The acupoint puncture group formed a potential acupuncture effect in the acupoint area by continuously tightening the steel needle on Ilizarov ring external fixator during the post-operative adjustment. Within three months after wearing external fixator, the knee pain symptoms of knee osteoarthritis were relieved rapidly, continuously and effectively, which was significantly better than that of the anatomical puncture group.
Acupuncture Points ; Aged ; Female ; Humans ; Ilizarov Technique ; Knee Joint ; Male ; Middle Aged ; Osteoarthritis, Knee ; therapy ; Punctures ; Tibia ; Treatment Outcome

Background: The Omicron variant has become the most prevalent SARS-CoV-2 variant. Omicron is known to induce milder lesions compared to the original Wuhan strain. Fatal infection of the Wuhan strain into the brain has been well documented in COVID-19 mouse models and human COVID-19 cases, but apparent infections into the brain by Omicron have not been reported in human adult cases or animal models. In this study, we investigated whether Omicron could spread to the brain using K18-hACE2 mice susceptible to SARS-CoV-2 infection. Results: K18-hACE2 mice were intranasally infected with 1 × 105 PFU of the original Wuhan strain and the Omicron variant of SARS-CoV-2. A follow-up was conducted 7 days post infection. All Wuhan-infected mice showed > 20% body weight loss, defined as the lethal condition, whereas two out of five Omicron-infected mice (40%) lost > 20% body weight. Histopathological analysis based on H&E staining revealed inflammatory responses in the brains of these two Omicron-infected mice. Immunostaining analysis of viral nucleocapsid protein revealed severe infection of neuron cells in the brains of these two Omicron-infected mice. Lymphoid depletion and apoptosis were observed in the spleen of Omicron-infected mice with brain infection. Conclusion Lethal conditions, such as severe body weight loss and encephalopathy, can occur in Omicron-infected K18-hACE2 mice. Our study reports, for the first time, that Omicron can induce brain infection with lymphoid depletion in the mouse COVID-19 model.