Occurrence state of fluoride in barite ore and the complexation leaching process

Barite ore is typically associated with difficult-to-remove vein minerals, but commercial barite products require a high BaSO4 content. We investigated the occurrence state of fluoride in barite ore using various analytical techniques, which indicated that elemental fluorine in barite predominantly exists as fluorite. Fluoride was then leached from barite ore via complexation. The effects of HCl and AlCl3 concentrations, temperature, time, and liquid-solid ratio on the leaching rate were examined, and the leaching conditions were optimized using an orthogonal array method. The fluorine leaching rate approached 93.11% after stirring for 30 min at 90 °C and 300 rpm with 3 mol/L HCl, 0.4 mol/L AlCl3, a liquid-solid ratio of 10:1 mL/g, and an ore sample size of -75 μm + 48 μm. According to the leaching kinetics, the process conformed to the solid membrane diffusion control model at a high temperature and the joint chemical reaction-diffusion control model at a low temperature. The apparent activation energy was 56.88 kJ/mol. Furthermore, aluminum and fluorine coordination numbers increased with increasing Al3+/F- molar concentration ratios. Competing complexation reactions of Al3+, H+, and F- occurred at three levels. This complexation approach effectively leaches fluoride from barite, improves barite product quality, and reduces environmental pollution.

[Application of novel non-endoscopic device in the screening and early diagnosis of esophageal cancer]

Esophageal cancer (EC) is a dreadful disease with a poor prognosis and poses heavy health burden worldwide. Developing effective methods to identify high-risk individuals is urgently needed for preliminary screening before endoscopy. The novel non-endoscopic device has the potential advantages of low cost, simple operation, and minimal invasiveness. Approximately 90% of participants can swallow the device successfully with high safety profiles, and sufficient esophageal exfoliated cells can be collected for cytological examination and biomarker detection. Cytological examination based on the device combined with trefoil factor 3 (TFF3) protein or DNA methylation examinations could effectively screen Barrett's esophagus-associated dysplasia and early esophageal adenocarcinoma, but large prospective studies are needed to further validate the diagnostic value of this device to improve the quality of evidence. Although the device-based cytological examination in combination with biomarker detection holds promise in the early screening of esophageal squamous dysplasia and early esophageal squamous cell carcinoma, related research is still in its infancy, and there is still a lack of sufficient evidence for population screening in China. Active research into the application of this novel non-endoscopic device in EC screening and early diagnosis is of great significance for optimizing EC screening strategies and improving the early diagnosis of EC.

Determination of carbonate content in barite ore by headspace gas chromatography

This paper reports a method for determining the carbonate content in barite ore using headspace gas chromatography. Based on the acidification reaction, the carbonate in the barite ore was converted to CO₂ in a closed headspace vial. When the carbonate content was significant, the pressure caused changes in the CO₂ and O₂ signals and affected the measurement accuracy. It was found that carbonate content is proportional to the intensity ratio of the CO₂ to O₂ signals. Thus, the carbonate content in barite ore can be measured indirectly using a theoretical model. The results showed that the carbonate in 3 g of barite ore sample with a particle size of 74 μm could react completely with a hydrochloric acid solution (2 mol/L) at 65°C for 5 min. The method described herein had good precision (relative standard deviation < 4.14%) and accuracy (relative differences < 6.12%). Further, the limit of quantification was 0.07 mol/L. Owing to its simplicity and speed, this method can be used for the batch determination of carbonate content in barite ore.

[Correlation analysis of age and microbial characteristics in saliva and feces of high-risk population of upper gastrointestinal cancer]

Objective: To explore the correlation between age and diversity and microbial composition in saliva and feces microbiota in high-risk population of upper gastrointestinal cancer. Methods: Based on the national project on early diagnosis and early treatment of upper gastrointestinal cancer, 38 participants were enrolled in Linzhou in Henan province in August 2019. The participant information was collected by questionnaire. Saliva and feces specimens were collected from each participant for 16S rRNA sequencing and bioinformatics analysis. Spearman rank correlation was used to analyze the correlation between age and α diversity (Observed ASVs and Shannon index) and relative abundance of microbiota (phyla, genera, and species) in saliva and feces. Results: The median age (age range) of 38 participants was 54 (43-60) years old, and there were 16 males (42.1%). The Observed ASVs of saliva was negatively correlated with age (r_s=-0.35, P<0.05), but the observed ASVs of feces was not correlated with age. In saliva, the relative abundance of Treponema (r_s=‒0.44, P<0.05), Alloprevotella (r_s=‒0.42, P<0.05), and Porphyromonas (r_s=‒0.41,P<0.05) were significantly negatively correlated with age. At the species level, the relative abundance of Porphyromonas endodontalis, Alloprevotella tannerae, Haemophilus influenza, Moraxella bovoculi, Prevotella sp.oral clone ID019, and Prevotella sp.oral clone ASCG10 in saliva were significantly negatively correlated with age, and the r_s values were -0.50, -0.40, -0.38, -0.35, -0.33 and -0.33 (P<0.05), respectively. In feces, the relative abundance of Enterobacteria (r_s=-0.35, P<0.05), Escherichia (r_s=-0.33, P<0.05), and Bifidobacteria (r_s=0.33, P<0.05) were correlated with age. At the species level, the relative abundance of Romboutsia sedimentorum, Citrobacter murliniae, and bacteroides uniformis in feces were correlated with age, and the r_s values were -0.42, -0.37 and 0.36 (P<0.05), respectively. Conclusion: Age of the high-risk population of upper gastrointestinal cancer is correlated with the relative abundance of microbiota in saliva and feces.

[Changes of serum lipid profiles and the correlation analysis in clinic-pathological features of pancreatic cancer patients]

Objective: To examine the characteristics of blood lipid profile and the correlation with clinic-pathological features of pancreatic cancer patients. Methods: The clinical and pathological data of 265 pancreatic cancer patients who received radical surgical treatment at Department of General Surgery,Qilu Hospital,Shandong University from January 2013 to September 2020 were collected and analyzed retrospectively. Among the 265 pancreatic cancer patients,there were 170 males and 95 females,with age of (61.0±9.6)years(range:28 to 86 years). General information,lipid indicators and clinic-pathological information were collected from electronic medical record system,and follow-up information gained by telephone. According to level of serum lipid in pancreatic cancer patients,265 patients were divided into dyslipidemia group(n=115) and normal lipid group(n=150). Pearson χ2,Student's t tests, variance analysis or univariate Logistic regression was used to analyze the correlation between dyslipidemia and clinico-pathological characteristics of pancreatic cancer,respectively. Kaplan-Meier survival curve was used to assessed the influence of dyslipidemia on prognosis of pancreatic cancer patients. Results: In 265 pancreatic cancer patients,115(43.4%)of them had dyslipidemias,and the most common form was increase of triglyceride(TG)(72.2%). In pancreatic cancer with dyslipidemias group,patients with body mass index ≥25 kg/m2 had higher proportion than normal lipid group(36.1%(26/72) vs. 21.2%(21/99),χ²=4.643,P=0.031); The proportion of carcinoma located at head of pancreas(83.5%(96/115) vs. 40.7%(61/150),χ²=49.412,P<0.01), staging of T1/T2(79.1%(91/115) vs. 60.7%(91/150),χ²=10.316,P<0.01) and lymphatic metastasis(36.5%(42/115) vs. 22.7%(34/150),χ²=6.007,P<0.01) were higher. In patients of pancreatic cancer, dyslipidemias were closely associated with tumor location(OR=10.529,P<0.01)and body mass index(OR=3.671,P=0.008). Serum lipid profile results showed that TG,total cholesterol and high-density lipoprotein(HDL) disorders were associated with tumor location(P<0.05). TG disorder had association with body mass index(P<0.05), and HDL disorder had association with tumor stage(P<0.05). Moreover, the result of survival analysis showed that dyslipidemia was not a factor to impact the prognosis of pancreatic cancer patients underwent surgery(P>0.05). Conclusions: In pancreatic cancer patients,TG disorder was the most common type of dyslipidemia. Dyslipidemia has closely association with clinicopathologic features,including tumor location,body mass index,tumor stage. However,dyslipidemia had little effect on prognosis of pancreatic cancer patients.

[Well differentiated grade 3 gastroenteropancreatic neuroendocrine tumors:new insights into diagnosis and therapeutic strategy]

Gastroenteropancreatic neuroendocrine tumor G3(GEP-NET G3) is a novel subtype of neuroendocrine neoplasms proposed in 2019,which has unique biological behavior characteristics. However,there are still many challenges and controversies in its diagnosis and treatment. There are obvious differences between GEP-NET G3 and neuroendocrine carcinoma (NEC) in genetic alterations and molecular profiles. The most frequently mutated genes in NET G3 are MEN1,DAXX/ATRX,while in NEC,TP53 and Rb are the most frequently mutated genes. Currently,the mainstream view is that NET G3 and NEC are two distinct diseases with different genetic backgrounds,and NET G3 will not develop into NEC. Several clinical and pathological factors should be considered to distinguish GEP-NET G3 and NEC,which including patients' medical history,histopathological morphology of neoplasms,Ki-67 index,immunohistochemical results of TP53,Rb,DAXX/ATRX and other markers. Multidisciplinary treatment,including radical resection,chemotherapy,targeted therapy,peptide receptor radionuclide therapy,immunotherapy should be applied in patients with GEP-NET G3. Overall,given its relatively indolent biological behavior,the therapeutic strategy should be more actively. Although the cure strategy of NET G3 has many similarities with NET G1/2,it is completely different from NEC.

[Analysis and comparison of the clinical features and prognosis between extra - gastrointestinal stromal tumors and duodenal gastrointestinal stromal tumors]

Objective: To investigate the differences of clinicopathological features, diagnosis, treatment and prognosis between patients with extra-gastrointestinal stromal tumors (EGIST) and duodenal gastrointestinal stromal tumors (DGIST). Methods: A retrospective case - control study was performed. Case inclusion criteria: (1) tumor confirmed by histology and pathology; (2) primary tumor locating in the extra - gastrointestinal tract or duodenum; (3) without other synchronous tumors; (4) complete clinical and pathological data. Clinical data of 20 EGIST patients and 32 DGIST patients from March 2011 to September 2016 at Department of Gastrointestinal Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine were retrospectively collected and analyzed. The observational parameters included clinicopathological characteristics, treatment and prognosis conditions. Continuous data of abnormal distribution were expressed as median (range) and compared using the Mann-Whitney U-test. Survival curves were drawn by the Kaplan-Meier method and compared with the Log-rank test. Results: Of the 20 EGIST patients, 8 were males and 12 were females with age of 61.0 (30.0 to 86.0) years and of the 32 DGIST patients, 12 were males and 20 were females with age of 55.5 (27.0 to 70.0) years. Compared with DGIST patients, EGIST patients were older (U=188.000, P=0.012], had larger tumor size [10.0 (3.0 to 29.0) cm vs. 4.0 (1.5 to 10.0) cm, U=98.500, P<0.001] and higher ratio of high risk classification [85.0% (17/20) vs. 12.5% (4/32), χ(2)=26.870, P<0.001]. Among the 20 EGIST patients, 5 were diagnosed with distal metastasis and received imatinib (400 mg/d), and the other 15 patients underwent radical resection who were included in survival analysis. All the 32 DGIST patients underwent radical resection. The median follow-up of whole group was 43 (14 to 76) months. The 3-year recurrence/metastasis-free survival rate of 15 cases undergoing radical resection in the EGIST group was 85.6%, which was lower than that of the DGIST group (88.6%), and the difference was not statistically significant (P=0.745). There was no significant difference in the 3-year overall survival rate between the EGIST group (92.9%) and the DGIST group (100%) (P=0.271). Conclusions: As compared to DGIST, EGIST mostly occurs in those with older age, larger tumor size and higher risk grade. The prognosis of EGIST patients after radical resection is similar to that of DGIST patients.

Effects of isomaltooligosaccharide and Bacillus supplementation on sow performance, serum metabolites, and serum and placental oxidative status

This study investigated the effects of isomaltooligosaccharide (IMO) and Bacillus supplementation on sow performance, serum metabolites, and serum and placental oxidative status. Multiparous gestating sows (n = 130) with similar body conditions were randomly allocated to five groups (n = 26) receiving a basal diet (CON group) or a basal diet supplemented with 0.5% IMO (IMO group); 0.5% IMO and 0.02% Bacillus subtilis (IMO + S group); 0.5% IMO and 0.02% Bacillus licheniformis (IMO + L group); or 0.5% IMO, 0.02% Bacillus subtilis, and 0.02% Bacillus licheniformis (IMO + S+L group). There were no significant differences in the litter sizes among all dietary groups. The average piglet birth weight was improved in all treatment groups, and the placental efficiency was greater in the IMO + S and IMO + S+L groups than in the CON group (P < 0.05). The IMO + S+L group had increased the low-density lipoprotein cholesterol and reduced the total cholesterol in umbilical venous serum (P <  0.05). Additionally, the malondialdehyde concentrations were greater in umbilical venous serum of piglets in all treatment groups relative to that in the CON piglets (P <  0.05). The placental total antioxidant capacity was increased in the IMO+L and IMO+S+L groups (P <  0.05). Furthermore, the growth hormone concentration in umbilical venous serum was greater (P <  0.05) in all treatment groups. Overall, IMO and Bacillus supplementation during late gestation resulted in a changed metabolism of sows, improved the placental antioxidant capacity, and increased the growth hormone concentrations in umbilical venous serum, which ultimately improved the piglet birth weight and placental efficiency.

Modulators for Terahertz Communication: The Current State of the Art

With the increase of communication frequency, terahertz (THz) communication technology has been an important research field; particularly the terahertz modulator is becoming one of the core devices in THz communication system. The modulation performance of a THz communication system depends on the characterization of THz modulator. THz modulators based on different principles and materials have been studied and developed. However, they are still on the way to practical application due to low modulation speed, narrow bandwidth, and insufficient modulation depth. Therefore, we review the research progress of THz modulator in recent years and evaluate devices critically and comprehensively. We focus on the working principles such as electric, optical, optoelectrical, thermal, magnetic, programmable metamaterials and nonlinear modulation methods for THz wave with semiconductors, metamaterials, and 2D materials (such as graphene, molybdenum disulfide, and tungsten disulfide). Furthermore, we propose a guiding rule to select appropriate materials and modulation methods for specific applications in THz communication.

[Preparation and evaluation of blank and doxorubicin loaded poly (acrylic acid) microspheres for embolization]

OBJECTIVE

To prepare ion exchange doxorubicin-loaded poly (acrylic acid) microspheres (DPMs) and evaluate the properties of these chemoembolic agents.

METHODS

Poly (acrylic acid) microspheres (PMs) without drug were prepared by inverse suspension polymerization method and then doxorubicin was loaded by ion exchange mechanism to prepare DPMs. Optical microscope was used to investigate the morphology and particle size distribution of PMs and DPMs; fluorescence microscope and confocal microscope were used to observe the distribution of doxorubicin after drug loading. Elasticities of both the microspheres were evaluated by texture analyzer. High performance liquid chromatography (HPLC) method was established to determine the drug loading behavior of PMs and releasing behavior of DPMs. The in vivo embolic property was evaluated by embolizing the hepatic artery of a rabbit with 0.1 mL of DPMs.

RESULTS

PMs and DPMs were both spherical in shape, smooth in surface and dispersed well. Doxorubicin was mainly in the outer area inside of DPMs and distributed evenly. The average particle size of PMs and DPMs were (283±136) μm and (248±149) μm, respectively. PMs and DPMs both had good compression ability with the Young's modulus of (62.63±1.65) kPa and (93.94±1.10) kPa separately. PMs reached the drug loading balance at 12 h, and the entrapment efficiency was greater than 99%. Drug loading of PMs in doxorubicin solution at the concentration of 5.0 g/L and 12.5 g/L was (19.78±0.27) g/L and (49.45±0.37) g/L, respectively. Doxorubicin released slowly from DPMs in PBS and the accumulative release percentages of DPMs with corresponding drug loading were 6.82%±0.02% and 2.83%±0.10% after 24 h, respectively. Arterial angiograms showed that the hepatic artery of the rabbit was successfully embolized with DPMs.

CONCLUSION

DPMs with good performance of loading doxorubicin could be a potential embolic agent for transcatheter arterial chemoembolization.

[Application of da Vinci robot's bilateral axillo-breast approach in thyroid surgery of obese patients]

Objective:To discuss the effect of obesity on the operation of thyroid gland surgery and surgical results.Method:The clinical data of 446 patients who underwent robot thyroid surgery through bilateral axillo-breast approach (BABA) from the General Hospital of Jinan Military region from February 2014 to November 2017 were analyzed retrospectively, and the patients were divided into BMI<25 kg/m²; group, BMI 25-30 kg/m²; group and BMI>30 kg/m²; group according to body mass index (BMI). The operative complications were compared between the three groups of benign and malignant patients, such as operation time, postoperative lead flow, postoperative hospitalization time, tumor size (malignant), lymph node metastasis (malignant), cosmetic satisfaction score, laryngeal nerve injury and parathyroid function decrease. Statistical methods using Variance analysis and χ² test to compare the differences between the two groups of indicators, difference is statistically significant (P<0.05).Result:The difference of operation time, postoperative average hospitalization time and postoperative drainage fluid volume in 3 groups was not statistically significant（P>0.05）. ①Intraoperative and postoperative pathological results were benign: BMI<25 kg/m²; group 69 cases, BMI 25-30 kg/m²; group 48 cases, BMI>30 kg/m²; group 8 cases, temporary recurrent laryngeal nerve injury were 1 case, 0 case and 0 case respectively, temporary parathyroid function decrease 3 cases, 2 cases and 1 case. ②Intraoperative and postoperative pathological results were malignant:BMI<25 kg/m²; group 180 cases, BMI 25-30 kg/m²; group 119 cases,BMI>30 kg/m²; group 22 cases, temporary recurrent laryngeal nerve injury were 2 cases,1 case and 0 case respectively, temporary parathyroid dysfunction in 64 cases,29 cases and 5 cases respectively.③1 patient in BMI<25 kg/m²; group had lymphatic leakage after operation, 1 patient in BMI 25-30 kg/m²; group had subcutaneous tunnel hemorrhage, and 1 patient had lymphatic leakage during operation.Conclusion:For overweight or obese patients, the da Vinci robot thyroid operation is reliable, does not increase the risk of surgical complications, but also has a good cosmetic effect.

[BABA of da Vinci robot thyroid surgery in the standard treatment of thyroid cancer surgery]

Thyroid cancer is the most common malignant tumor in endocrine surgery. Surgery is the first choice for most patients with thyroid cancer. Da Vinci robot system as the auxiliary system is the most advanced endoscopic surgery, largely to fill the cavity mirror device cannot bend, complex operation and so on insufficiency, has now become an important way of surgical treatment of thyroid cancer, and its curative effect, high safety, but because of the economic cost is higher, is currently not widespread popularity.

[Relationship between 25-hydroxyvitamin D levels and idiopathic benign paroxysmal positional vertigo in female patients]

Objective: To investigate the relationship between serum 25-hydroxyvitamin D[25(OH) D] levels and idiopathic benign paroxysmal positional vertigo (BPPV) in female patients. Methods: A total of 67 women diagnosed with idiopathic BPPV were selected as the study group between January and December 2016 in Ningbo No.2 Hospital, and 95 healthy women without a history of vertigo or dizziness were selected as the control group. The data of height, weight, histories of hypertension and diabetes mellitus were collected, and serum 25(OH) D levels were measured. The number of the recurrence and canalith repositioning maneuvers were recorded during the one-year follow-up. Results: No significant differences of age, body mass index, histories of hypertension and diabetes mellitus between patients with BPPV and healthy controls (all P>0.05) .The serum 25 (OH) D levels were significantly lower in patients with idiopathic BPPV than in healthy controls [(50.56±13.36) nmol/L vs (56.55±16.21) nmol/L, t=-2.485, P=0.014]. BPPV patients with low level of 25(OH) D showed a significant increase in the number of canalith repositioning maneuvers required and the recurrence rate. The regression analyses demonstrated that 25(OH)D deficiency was associated with BPPV with an odds ratio of 2.054 (95% CI: 1.088-3.877, P=0.026). Conclusion: 25(OH) D deficiency may be a risk factor of BPPV.

[Study on bone metabolism in postmenopausal women with idiopathic benign paroxysmal positional vertigo]

Objective: To analyze the bone mineral density and serum osteocalcin levels in postmenopausal women with idiopathic benign paroxysmal positional vertigo. Methods: A total of 64 postmenopausal women with idiopathic BPPV were selected as the study group, and 98 postmenopausal healthy women were selected as the control group. Bone mineral density and serum osteocalcin levels were analyzed and compared between the groups.χ(2) test was used for numeration data and t test was used for measurement data. Results: The prevalence of osteoporosis or osteopenia in BPPV group 67.2% (43/64) was significantly higher than that in the control group 51.0% (50/98) (χ(2)=4.139, P=0.042). Among BPPV subjects, there was a negative correlation between osteocalcin and bone density T (r=-0.469, P<0.001). Osteocalcin was found in normal bone mass subgroup (13.61±4.32)μg/L, decreased bone mass subgroup (17.49±7.61)μg/L, and osteoporosis subgroup (20.83±6.72)μg/L, respectively, and the difference was statistically significant (F=5.39, P=0.007). Conclusions: Bone mineral density in BPPV group is lower than that in control group. The lower the bone mineral density of the patients, the higher the osteocalcin in BPPV group.

RAPID COMMUNICATION: Generation of FGF5 knockout sheep via the CRISPR/Cas9 system

Sheep are an important source of fiber production. Fibroblast growth factor 5 (FGF5) is a dominant inhibitor of length of the anagen phase of the hair cycle. Knockout or silencing of the gene results in a wooly coat in mice, donkeys, dogs, and rabbits. In sheep breeding, wool length is one of the most important wool quality traits. However, traditional breeding cannot accurately and efficiently mediate an advanced genotype into the sheep genome. In this study, we generated 3 knockout sheep via the 1-step clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system. Sequencing analysis confirmed that mutations in the gene existed in all germ lines of 3 founders: besides the intact sequence, 3 kinds of deletions in the gene (including 5, 13, and 33 bp) were detected. The changes in the primary and senior structure of the FGF5 protein due to the 3 deletions in founders suggested that the FGF5 protein was dysfunctional. In addition, the expression level of intact mRNA in heterozygous individuals decreased compared with the wild types ( < 0.01). Functionally, we discovered that wool length in founders was significantly longer than in wild types ( < 0.05). Collectively, the knockout sheep with the longer wool length phenotype will provide an efficient way for fast genetic improvement of sheep breeding and promote the development of wool industry.

[Random clinical study about application value of oxycodone in radiofrequency ablation of hepatocellular carcinoma]

Objective: To evaluate the clinical effect and safety of oxycodone hydrochloride in the anesthesia for percutaneous radiofrequency ablation (PRFA) in hepatocellular carcinoma. Methods: Between March and December 2015, 60 cases of hepatocellular carcinoma patients undergoing percutaneous radiofrequency ablation surgery in Peking University Cancer Hospital were randomly divided into three groups: oxycodone group (group Q), fentanyl group (group F) and dezocine group (group D), 20 cases in each group. Respectively intravenously injection oxycodone 0.1 mg/kg, fentanyl 0.001 mg/kg, dezocine 0.1 mg/kg before surgery. After the surgeon completed puncture administer propofol to maintain anesthesia. Recorded mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), oxygen saturation (SpO₂) changes in each group at entrance, beginning of radiofrequency ablation (T1), radiofrequency ablation began after 10 minutes (T2), the end of the surgical and awake. Observe the analgesia effect, respiratory depression, nausea, vomit and other complications. Postoperative pain scores were recorded.Using ANOVA, repeated measure variance analysis, SNK test, χ² test and other tests to evaluate the anesthetic effect indexes. Results: The observation completed in all patients. Patients of three groups had no significant differences in general information. No significant difference between MAP, HR and SpO₂ at each time points among the three groups. At the T1 time point (group Q: (11.7±1.6)/min, group D: (12.1±1.7)/min, group F: (10.3±2.3)/min, F=5.068, P=0.009) and T2 time point (group Q: (11.9±1.3)/min, group D: (12.2±1.4)/min, group F: (10.7±1.3)/min, F=7.024, P=0.002), RR in group F were lower than in group Q and group D. Pain visual analogue scores after waking (group Q: 0.2±0.7, group D: 0.3±0.7, group F: 1.7±1.5, F=12.981, P=0.000) and postoperative pain score of 1 hour (group Q: 2.0±0.9, group D: 1.8±0.8, group F: 4.3±0.9, F=42.362, P=0.000) in the group Q and group D were significantly lower than in group F. The body movements in group Q and group D were significantly less than in group F (3 cases, 3 cases, 9 cases, χ²=6.400, P=0.041 ). Intraoperative respiratory depression in group Q and group D were lower than group F (3 cases, 2 cases, 9 cases, χ²=8.012, P=0.018). Conclusions: Oxycodone hydrochloride can be used safely and effectively for radiofrequency ablation. It has favorable hemodynamic stability, lower incidence of respiratory depression, and advantage in terms of postoperative pain.

Population genetic structure of critically endangered salamander (Hynobius amjiensis) in China: recommendations for conservation

Amji's salamander (Hynobius amjiensis) is a critically endangered species (IUCN Red List), which is endemic to mainland China. In the present study, five haplotypes were genotyped for the mtDNA cyt b gene in 45 specimens from three populations. Relatively low levels of haplotype diversity (h = 0.524) and nucleotide diversity (π = 0.00532) were detected. Analyses of the phylogenic structure of H. amjiensis showed no evidence of major geographic partitions or substantial barriers to historical gene flow throughout the species' range. Two major phylogenetic haplotype groups were revealed, and were estimated to have diverged about 1.262 million years ago. Mismatch distribution analysis, neutrality tests, and Bayesian skyline plots revealed no evidence of dramatic changes in the effective population size. According to the SAMOVA and STRUCTURE analyses, H. amjiensis should be regarded as two different management units.

[Mechanisms for reversal of pulmonary hypertension by rapamycin in rats]

OBJECTIVE

To investigate the effects of rapamycin (RAP) on pulmonary hypertension (PH) in rats, and to provide new insights into medication selection for the clinical treatment of PH.

METHODS

Fifty male Sprague-Dawley rats were randomly divided into blank control, PH model, solvent control, RAP 1, and RAP 2 groups. A rat model of PH was induced by left pneumonectomy (PE) and monocrotaline (MCT). At 5 days after PH model establishment, the solvent control group and the RAP 1 group received an intramuscular injection of solvent and RAP, respectively. At 35 days after PH model establishment, the RAP 2 group received an intramuscular injection of RAP. The mean pulmonary artery pressure (mPAP) and the right ventricle/left ventricle plus septum weight ratio (RV/LV+S) were measured in each group. Histopathological changes in the right lung were evaluated by hematoxylin-eosin (HE) staining. The relative expression of alpha-smooth muscle actin (α-SMA) and smooth muscle protein 22-alpha (SM22α) in each group was determined using real-time PCR.

RESULTS

At 35 days after surgery, the PH model and the solvent control groups had significantly higher mPAP and RV/LV+S than the blank control group, while the RAP 1 and the RAP 2 groups had significantly lower mPAP than the solvent control group (P<0.05). The RV/LV+S in the RAP 1 group was significantly lower than that in the solvent control group (P<0.05); however, there was no significant difference in RV/LV+S between the RAP 2 and the solvent control groups (P>0.05). HE staining in the right lung showed the substantially thickened pulmonary artery wall and narrowed arterial lumen in the PH model and the solvent control groups compared with the blank control group. Different degrees of reversal of the pulmonary artery wall thickening were observed after RAP administration. The results of real-time PCR revealed that the relative expression of α-SMA and SM22α in the PH model and the solvent control groups was significantly lower than in the blank control group, while the relative expression of α-SMA and SM22α in the RAP 1 and the RAP 2 groups was significantly higher than in the solvent control group (P<0.05).

CONCLUSIONS

RAP can reverse the increase in pulmonary artery pressure and the right ventricular hypertrophy probably by regulation of the phenotypic conversion of vascular smooth muscle cells.

[Relationship between Hes-1 and airway inflammation and remodeling in a rat model of asthma]

OBJECTIVE

To study the changes of Hes-1, the target gene of Notch signaling pathway, and its relationship with airway inflammation and remodeling in a rat model of asthma.

METHODS

Forty-eight rats were randomly divided into an asthma group and a control group. The rats in the asthma group were sensitized and challenged by ovalbumin (OVA), and normal saline was used in the control group. Two groups were further divided into 3 subgroups according to time points after challenging, i.e. 4 weeks, 8 weeks and 12 weeks (n=8 rats each). Pathological changes of lungs were observed by light microscopy and the thickness of bronchial smooth muscle layer (Wam) was measured. The levels of IL-4 and INF-γ in rat serum and bronchoalveolar lavage fluids (BALF) were measured using ELISA. Expression levels of Hes-1 protein and mRNA were determined by immunohistochemistry and quantitative real-time PCR respectively.

RESULTS

Together with the extension of challenging, the Wam of rats in the asthma group increased, a decrease of INF-γ level and an increase of IL-4 level in serum and BALF were also observed, and the differences were statistically significant compared with those in the corresponding control group (P<0.05). Hes-1 protein and mRNA levels also increased gradually after OVA challenging and were higher than those in the control group (P<0.05). The levels of Hes-1 protein and mRNA were positively correlated with Wam and IL-4 in serum and BALF, but were inversely correlated with INF-γ in serum and BALF (P<0.05).

CONCLUSIONS

Levels of Hes-1 protein and mRNA increased, which were closely related with the levels of airway inflammatory factors and remodeling of airway smooth muscle. Hes-1 may play an important role in the pathogenesis of asthma.

Manipulation of monoubiquitin improves salt tolerance in transgenic tobacco

Ubiquitin (Ub) is regarded as a stress protein involved in many stress responses. In this paper, sense and antisense transgenic tobacco plants, as well as the wild type and vector control, were used to study the role of Ub in salt tolerance of plants. In sense Ta-Ub2 transgenic tobacco plants, there was higher expression of Ub protein conjugates than in the wild type and vector control, but the reverse trend was observed in antisense Nt-Ub1 transgenic plants. The germination rate of tobacco seed, growth status and photosynthesis of the tobacco plants suggested that over-expressing Ub promoted the growth of transgenic tobacco plants and enhanced their salt tolerance, but the opposite effect was seen in plants with repressed Ub expression. Changes in antioxidant capacity may be one of the mechanisms underlying Ub-regulated salt tolerance. Furthermore, improved tolerance to a combination of stresses was also observed in the sense transgenic tobacco plants. These findings imply that Ub is involved in the tolerance of plants to abiotic stress.

A TiO2 nanostructure transformation: from ordered nanotubes to nanoparticles

Transformation of TiO2 nanotubes (NTs) to truncated tetragonal bipyramidal shape nanoparticles (NPs) was observed upon thermally annealing titanium dioxide (TiO2) ordered nanotube arrays in fluorine ambient, resulting from the reaction of fluorine ions (F(-)) from the electrolyte residues in long nanotubes grown by anodization in ethylene glycol+NH4F electrolyte. The size of the TiO2 nanoparticles formed depends on the fluorine concentration and can be controlled from 20 to 500 nm. The crystal and optical properties of the nanoparticle layers are superior compared with those of nanotube arrays which are also annealed but without undergoing a morphology transformation, as was shown by means of x-ray diffraction and photoluminescence spectroscopy measurements. The NT-NP transformation mechanism was studied by analyzing the initial stages of the NT-NP transformation. This was achieved by terminating the annealing process in F ambient after 1-5 min. It was found that amorphous NTs first contract, then break down, and finally merge and crystallize to form NPs.

The anodization voltage influence on the properties of TiO2 nanotubes grown by electrochemical oxidation

A systematic study of titanium dioxide (TiO2) nanotubes (NTs) grown by electrochemical anodization in NH4F + glycerol electrolyte has been carried out in a broad range of anodization voltage of 5-350 V and acid concentration of 0.1-0.7 wt%. It is found that NTs can be grown in the voltage range from 10 to 240 V. The maximum NH4F acid concentration at which NTs can be formed decreases with the anodization voltage (V(a)). The maximum NH4F acid concentration is 0.7% for V(a)<60 V, and it decreases to 0.1% at V(a) = 240 V. Glancing angle x-ray diffractometer (GAXRD) measurements show that as-grown amorphous TiO2 transforms to the anatase phase when annealed at 400 degrees C, and further transforms to the rutile phase at annealing temperatures higher than 500 degrees C. The transition temperature from anatase to rutile phase depends on the anodization conditions. The electrical resistivity of the NT increases by eight orders of magnitude when V(a) increases from 10 to 240 V.