The Conversion of Non-Dispersed Polymers into Low-Potassium Anti-Collapse Drilling Fluids

Different drillingfluid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingfluid into a low potas-sium anti-collapsing drillingfluid is investigated.Since the two drillingfluids belong to completely different types,the key to this conversion is represented by new inhibitors,dispersants and water-loss agents by which a non-dispersed drillingfluid can be turned into a dispersed drillingfluid while ensuring wellbore stability and reason-able rheology(carrying sand—inhibiting cuttings dispersion).In particular,the(QYZ-1)inhibitors and(FSJSS-2)dispersants are used.The former can inhibit the hydration expansion capacity of clay,reduce the dynamic shear force and weaken the viscosity;the latter can improve the sealing effect and reduce thefiltrate loss.The results have shown that after adding a reasonable proportion of these substances(QYZ-1:FSJSS-2)to the non-dispersed polymer drillingfluid,while the apparent viscosity,plastic viscosity,structural viscosity andfluidity index under-went almost negligible changes,the dynamic plastic ratio increased,and thefiltration loss decreased significantly,thereby indicating good compatibility.According to the tests(conducted in the Leijia area),the density was 1.293 g/cm3,and after standing for 24 h,the SF(static settlement factor)was 0.51.Moreover,thefiltration loss was reduced to 4.0 mL,the rolling recovery rate reached 96.92%,with excellent plugging and anti-collapse performances.

Comparison of virus-capsid mimicking biologic-shell based versus polymeric-shell nanoparticles for enhanced oral insulin delivery

Virus-capsid mimicking mucus-permeable nanoparticles are promising oral insulin carriers which surmount intestinal mucus barrier.However,the impact of different viruscapsid mimicking structure remains unexplored.In this study,utilizing biotin grafted chitosan as the main skeleton,virus-mimicking nanoparticles endowed with biologicshell(streptavidin coverage)and polymeric-shell(hyaluronic acid/alginate coating)were designed with insulin as a model drug by self-assembly processes.It was demonstrated that biologic-shell mimicking nanoparticles exhibited a higher intestinal trans-mucus(>80%,10 min)and transmucosal penetration efficiency(1.6–2.2-fold improvement)than polymeric-shell counterparts.Uptake mechanism studies revealed caveolae-mediated endocytosis was responsible for the absorption of biologic-shell mimicking nanoparticles whereas polymeric-shell mimicking nanoparticles were characterized by clathrin-mediated pathway with anticipated lysosomal insulin digestion.Further,in vivo hypoglycemic study indicated that the improved effect of regulating blood sugar levels was virus-capsid structure dependent out of which biologic-shell mimicking nanoparticles presented the best performance(5.1%).Although the findings of this study are encouraging,much more work is required to meet the standards of clinical translation.Taken together,we highlight the external structural dependence of virus-capsid mimicking nanoparticles on the mucopenetrating and uptake mechanism of enterocytes that in turn affecting their in vivo absorption,which should be pondered when engineering virus-mimicking nanoparticles for oral insulin delivery.

Optimization of Anti-Collapse Drilling Fluid Systems with High Potassium Content

The ash mudstone in some oil formations is highly water-sensitive.The oil formation is fractured,and the risk of well leakage and collapse is not negligible.This study presents a countermeasure for well collapse prevention,based on a“force-chemistry synergistic balance”approach and the utilization of environmentally friendly and efficient hydration inhibitors.The relevance of this approach is demonstrated considering a drilling fluid system with the high potassium content.The analysis shows that the system can maintain good rheological properties,filtration loss and suspension stability even after aging at 130℃ for 16 h.The primary roll recovery of rock chips is better than 98%.The secondary rolling recovery rate is 89%.The rapid water loss is close to zero.The effects of carrying rock,sand,hydration inhibition and dispersion of drill chips are all noticeable.

胰岛素样生长因子-1减少胎羊缺血性脑白质损伤后淀粉样前体蛋白表达(英文)

目的 淀粉样前体蛋白 (β APP)是脑白质损伤早期敏感的指标 ,并参与缺氧缺血性脑损伤机制。本研究观察胎羊缺血性脑白质损伤及胰岛素样生长因子 1(IGF 1)治疗对淀粉样前体蛋白 (β APP)表达的影响。方法 胎羊于胎龄 117 12 4天 (足月为 14 7天 )时通过双侧颈动脉阻塞 30min造成双侧脑缺血损伤 ,损伤后胎羊随机分为损伤组 (n =8)和重组人IGF 1(rhIGF 1)治疗组 (n =9) ;另设正常对照组 (n =5 ) ,为假手术动物。治疗组缺血后 90min经侧脑室注射 3μgrhIGF 1;损伤组经侧脑室注射等量人工脑脊液。缺血损伤后 96h结束实验 ,处死动物 ,取出胎羊 ,固定脑组织。免疫组化法检测脑白质胶质原纤维酸性蛋白 (GFAP)、β APP阳性细胞及白质内髓鞘碱性蛋白 (MBP)密度。应用免疫荧光双标记观察APP表达阳性细胞。结果 与正常对照组 (2 7.8± 4 .8)比较 ,缺血损伤组MBP密度 (4.7± 7.1,P <0 .0 0 1)明显减少。正常对照组未见 β APP阳性细胞 ,损伤后阳性细胞数明显增加 (49.6± 2 3.7,P <0 .0 0 1) ,rhIGF 1治疗可减少 β APP阳性细胞数 (17.9± 16 .5 ,P <0 .0 1)。免疫荧光双标记显示部分细胞为 β APP GFAP双标阳性细胞。 结论 胎羊缺血性脑白质损伤可导致星形胶质细胞表达β APP ,β APP表达增加可能与脑损伤有关?

Congenital left intrahepatic bile duct draining into gastric wall mimicking biliary reflux gastritis

Abnormalities and variations of the biliary ducts are not rare.Most aberrant bile ducts eventually drain into the descending part of duodenum through the papilla of vater.However,drainage of the left hepatic bile duct into the stomach is extremely rare.A 29-year old man was admitted to the hospital with the diagnosis of biliary reflux gastritis.Comprehensive imaging modalities were performed including electronic endoscopy,endoscopic ultrasonography,endoscopic retrograde cholangiopancreatography and magnetic resonance cholangio-pancreatography.Finally,congenital ectopic left intrahepatic bile duct draining into the stomach was found,which caused biliary reflux gastritis.The patient did not receive any surgery.Good recovery was achieved by medical treatment.

Synergistic effect of bromocriptine and tumor necrosis factor-a on reversing hepatoceiiuiar carcinoma multidrug resistance in nude mouse MDRl model of liver neoplasm

AIM： To investigate the effect of bromocripUne （BCT） and tumor necrosis factor-α ClNF-α） on hepatocellular carcinoma （HCC） multidrug resistance （MDR） in nude mouse HDR model of liver neoplasm. METHODS： Human hepatocarcinoma cell line HepG2t drug resistant hepatocarcinoma cell line HepG2/adriamycin （ADM） and hepatocarcinoma cell line transfected with TNF-α gene HepG2JADM/TNF were injected into the liver of nude mice via orthotopic implantation and MDR model of liver neoplasm in vivo was established （HepG2t ADM, TNF, BCT groups）. Among these groups, BCT group and TNF group were treated with BCT through gastric canal. Each group was divided into control group and chemotherapy group. Size and weight of the tumor were measured. Furthermore, tumor his^logical character and growth of the nude mice were observed and their chemosensitivity was tested. MDR-associated genes and proteins （MRP, LRP） of implanted tumors were detected by immunohistochemistry, reverse transcriptase polymerase chain reaction, and apoptosis rate of hepatocarcinoma cells was detected by TUNEL assay. RESULTS： The nude mouse model of each cell line was inoculated successfully. The tumor growth rate and weight were significantly different among groups. After chemotherapy, abdominal cavity tumor growth inhibition rate was higher in BCT group （67%） compared to ADM and TNF groups, and similar to HepG2group （54%）. MDRI and LRPmRNA could be detected in all groups, but TNF-α was detected only in TNF and BCT groups. Furthermore, MDR1 and LRP protein expression of tumors in TNF and BCT groups was low similar to HepG2 group. The apoptosis rate of hepatocarcinoma cells was much higher in BCT group than in other groups with TUNEL assay. CONCLUSION： BCT and TNF-a can reverse HCC MDR in nude mouse MDR1 model of liver neoplasm. 2005 The WJG Press and Elsevier Inc. All rights reserved

Modulating intestinal mucus barrier for nanoparticles penetration by surfactants

Improving peroral delivery efficiency is always a persistent goal for both small-molecule and macromolecular drug development. However,intestinal mucus barrier which greatly impedes drug-loaded nanoparticles penetration is commonly overlooked. Therefore,in this study,taking fluorescent labeled PLGA(poly(lactic-co-glycolic acid)) nanoparticles as a tool,the influence of anionic and nonionic surfactants on mucus penetration ability of nanoparticles and their mucus barrier regulating ability were studied. The movement of PLGA nanoparticles in mucus was tracked by multiple particles tracking method(MPT).Alteration of mucus properties by addition of surfactants was evaluated by rheology and morphology study. Rat intestinal villus penetration study was used to further evaluate penetration enhancement of nanoparticles. The effective diffusivities of the nanoparticles in surfactants pretreated mucus were increased by 2–3 times and the mucus barrier regulating capacity was also surfactant type dependent. Sodium dodecyl sulfate(SDS) increased the complex viscosity and viscoelastic properties of mucus,but poloxamer presented a decreased trend. Tween 80 maintained the rheological property of the mucus. With the mucus barrier regulated by surfactants,the penetration of nanoparticles in intestinal villus was obviously increased. In summary,the mucus penetration ability of nanoparticles could be enhanced by altering mucus microenvironment with surfactants. Tween 80 which largely retains the original mucus rheology and morphology properties may be a promising candidate for facilitating nanoparticle penetration through the mucus barrier with good safety profile.

Nursing ethics for prevention and control of major infectious disease outbreaks:Chinese expert consensus

Background Major infectious disease has become a serious threat to people’s health worldwide.As the world’s largest healthcare workforce and the core forces fighting against the epidemic,nurses are on the frontline of this battle.A number of ethical issues have given rise to numerous concerns that have largely affected nurses in different ways as they respond to the epidemic.In addition,excessive expectations from people can exert undue pressure,which can easily lead to burnout in nurses.Methods In this consensus,the expert panel method was used to develop and reach a consensus.The members involved in the formation of the consensus included an expert discussion panel and a consensus writing expert group,a methodologist,and four secretaries.After 16 rounds of online expert consultation and two rounds of expert panel meetings,the writing team analyzed and reviewed the 78 amendments suggested by the experts to develop a consensus on nursing ethics for prevention and control of major infectious disease outbreaks based on the ethical vision of life care.Results This expert consensus focuses on five essential domains:the responsibilities and rights of nurses,the nurse-patient relationship,the doctor-nurse relationship,and the relationship between society and nurses throughout the epidemic.Conclusions We hope this consensus can help nurses better understand and respond to the ethical issues and challenges in public health emergencies,and raise reasonable public expectations of the roles and responsibilities of nurses in these situations.

Expression and predictive value of miR-489 and miR-21 in melanoma metastasis

BACKGROUND Melanoma is a highly malignant skin tumour, and is one of the most rapidly growing malignant tumors in recent years. According to statistics, the morbidity of cancer increases with age, accounting for 1.6% of new cancer cases and 0.6% of deaths worldwide. Melanoma has a serious impact on society and families, thus it is of great significance to find biological markers related to the diagnosis and treatment of melanoma.AIM To explore the expression and predictive value of mir-489 and mir-21 in melanoma metastasis.METHODS A total of 60 patients with malignant melanoma treated at our hospital from June2017 to December 2018 were selected as a research group, while 40 healthy subjects were selected as a control group. qRT-PCR technique was used to detect miR-489 and miR-21 in serum of the two groups. ROC curve was drawn to evaluate the predictive value and diagnostic efficiency. Spearman test was used for correlation analysis. Logistic single-and multiple-factor analyses were performed to identify the risk factors related to melanoma metastasis.RESULTS The expression of miR-489 in the research group was significantly lower than that in the control group(P < 0.001). However, the expression of miR-21 in the research group was significantly higher than that in the control group(P < 0.001).The expression of miR-489 and miR-21 was related to TNM stage and metastasis(P < 0.001). In the diagnosis of melanoma patients, the sensitivity, specificity, and AUC of miR-489 alone were 75.56%, 80.00%, and 0.852, respectively. The sensitivity, specificity, and AUC of miR-21 alone were 77.78%, 82.22%, and 0.844,respectively. MiR-489 was negatively correlated with TNM stage of melanoma(r=-0.612, P < 0.001), while miR-21 was positively correlated with TNM stage(r =0.609, P < 0.001). Logistic single-and multiple-factor regression analyses showed that TNM stage, miR-489, and mir-21 were independent risk factors for malignant melanoma metastasis.CONCLUSION MiR-489 and miR-21 may participate in the process of melanoma occurrence,development, and metastasis, and can be used as potential serum biomarkers for melanoma metastasis diagnosis and disease assessment.

Tongue swelling as a manifestation of tongue metastasis from pulmonary sarcomatoid carcinoma: A case report

BACKGROUND Sarcomatoid carcinoma is a rare subtype of non-small-cell lung cancer,commonly associated with locally advanced disease,early metastasis,and poor prognosis.Tongue metastasis from lung cancer is a rare condition that may occur in advanced stage of the disease.CASE SUMMARY The patient was a 70-year-old female with a history of resected pulmonary sarcomatoid carcinoma(PSC)who presented with subacute tongue swelling,imparting the clinical impression of a lingual abscess.However,histologic examination of the partial glossectomy revealed a high-grade,poorly differentiated spindle and epithelioid carcinoma consistent with metastatic PSC.CONCLUSION Although uncommon,clinicians should be cognizant of the possibility of a metastatic process to the tongue mimicking a benign or inflammatory process.A high index of suspicion for metastatic disease should be maintained when tongue swelling is observed in patients with a known history of PSC.

差序格局是一种国家内文化吗?——中国地区差序文化的指标开发与验证、异质性分布及其影响

“差序格局”是中国社会科学应用最广、影响力最大的本土概念,但主流研究大多将它视为中国社会泛在性的文化特征,隐含假定它在中国各地区(例如省份)之间是同质的。对此,本文基于文化演化视角,探索差序文化省际异质性的存在性,以及这种异质性与当代省际不平衡发展的内在联系。在实证阶段,在开发出省际差序文化测量方法的基础上,对研究假设开展检验。研究发现:第一,差序文化在中国内部呈现出以“局部趋同,整体趋异”为特征的省际异质性;第二,这种异质性对于理解省际不平衡发展是重要的,它广泛解释了各省在政治、经济、社会和技术方面的发展差异。本文率先为差序文化的地区异质性提供了理论解释、经验证据和方法论工具,对于推动面向实证的差序格局研究具有重要价值。

Efficacy of intravitreal conbercept combined with panretinal photocoagulation for severe nonproliferative diabetic retinopathy without macular edema

AIM: To assess efficacy of intravitreal conbercept(IVC) injection in combination with panretinal photocoagulation(PRP) vs PRP alone in patients with severe nonproliferative diabetic retinopathy(SNPDR) without macular edema(ME).METHODS: Forty-eight patients with SNPDR without ME(56 eyes) were divided into the PRP group and IVC+PRP group(the pulse group) in this retrospective clinical study. Conbercept was intravitreally administered to patients in the pulse group 1 wk before treatment with PRP and followed up for 1, 3, and 6 mo. The best-corrected visual acuity(BCVA, log MAR), center foveal thickness(CFT), visual acuity(VA) improvement, and adverse reactions were compared between groups.RESULTS: In the PRP group, the BCVA reduced at 1 and 3 mo before improving at 6 mo. In the pulse group, baseline BCVA decreased continuously at 1 mo, increased at 3 and 6 mo. BCVA in the pulse group was better than that in the PRP group at 1, 3, and 6 mo. There was an increase in CFT in the PRP group during follow-up compared with baseline. In the pulse group, CFT was increased at 1 mo relative to baseline, steadily decreased to the baseline level at 3 and 6 mo. There was a more significant reduction in CFT in the pulse group during follow-up compared with the PRP group. The effective rates of VA in the PRP and the pulse groups were 81.48% and 100%, respectively. CONCLUSION: As PRP pretreatment, a single dose of IVC administration has beneficial effects for preventing PRPinduced foveal thickening and increasing VA in patients with SNPDR without ME.

Exploring the potential of functional polymer-lipid hybrid nanoparticles for enhanced oral delivery of paclitaxel

Most biopharmaceutics classification system(BCS)class IV drugs,with poor solubility and inferior permeability,are also substrates of P-glycoprotein(P-gp)and cytochrome P450(CYP450),leading to their low oral bioavailability.The objective of this study is to explore the potential of using functional polymer-lipid hybrid nanoparticles(PLHNs)to enhance the oral absorption of BCS IV drugs.In this paper,taking paclitaxel(PTX)as a drug model,PTX-loaded PLHNs were prepared by a self-assembly method.Chitosan was selected to modify the PLHN to enhance its mucoadhesion and stability.Three P-gp inhibitors(D-α-tocopherol polyethylene glycol 1000 succinate,pluronic P123 and Solutol RHS15)were incorporated into selected PLHNs,and a CYP450 inhibitor(the extract of VBRB,BC0)was utilized to jointly promote the drug absorption.Properties of all the PLHNs were characterized systemically,including particle size,zeta potential,encapsulation efficiency,morphology,stability,in vitro drug release,mucoadhesion,in situ intestinal permeability and in vivo systemic exposure.It was found mucoadhesion of the CS-modified PLHNs was the strongest among all the formulations tested,with absolute bioavailability 21.95%.P-gp and CYP450 inhibitors incorporation further improved the oral bioavailability of PTX to 42.60%,8-fold increase compared with that of PTX itself(4.75%).Taken together,our study might shed light on constructing multifunctional PLHNs based on drug delivery barriers for better oral absorption,especially for BCS IV drugs.

Probiotics' Preventive Effect on Pediatric Food Allergy: A Meta-analysis of Randomized Controlled Trials

Objective To investigate the preventive effect of probiotics on pediatric food allergy. Methods From MEDLINE bibliographical database, we searched and reviewed all randomized controlled trials on the preventive effects of probiotics on pediatric food allergies up to September 2013 and excluded the studies that do not meet inclusion criteria and extracted the data. Meta-analysis for the results of homogenous studies was performed using RevMan 5.0 and the co-effect was pooled by using fixed-effects model of relative risk(RR) ratios. Results Ten trials published between 2007 and 2012 including 2701 cases were included. Meta-analysis based on included data showed that the preventive effect of prenatal and postnatal probiotic supplementation on food allergies was not significant with the RR=0.88(95% CI: 0.76-1.03). Conclusion Present evidences cannot show in unequivocal terms that prenatal and postnatal probiotic supplementation will prevent food allergic diseases.

Synthesis, adsorption and selectivity of inverse emulsion Cd(Ⅱ) imprinted polymers

Inverse emulsion polymerization was employed to synthesize inverse emulsion Cd（Ⅱ） imprinted polymers （IEⅡ P）. The morphology and functional groups of IEⅡP were characterized by SEM,FTIR and TG. Static adsorption experiments and competitive adsorption test were used to evaluate the adsorption ability of IEⅡP. The adsorption capacity of polymers could reach 86.7 mg·g^-1 under the optimal adsorption conditions. The pseudo second order kinetic model and Langmuir isotherm model could be used to analyze the experimental data well. The adsorption process of IEⅡP was chemical adsorption process and monomolecular type. Thermodynamic parameters showed that the adsorption process was endothermic and could occur spontaneously. The selectivity coefficients k of Cd^2＋/v, Cd^2＋/Zn^2＋ and Cd^2＋/Cu^2＋ were 2.4998, 1.2437 and 4.6882, respectively. The proposed method provides a new thought for removing Cd（Ⅱ） in water samples.

中国省际心理资本:测量及其影响

心理资本是个体在成长和发展过程中表现出的一种积极心理特质,是促进个体自我成长和绩效提升最重要的心理资源之一。然而,现有研究多是从个人或团队层面探讨心理资本的影响机制,而很少将其拓展至更为宏观的层面。本文基于心理特质的地区差异理论,率先从宏观层面探讨了心理资本在中国各省份间的异质性及其影响。进一步地,基于心理资本的传统测量,本文利用中国综合社会调查(CGSS)数据构建了中国省际心理资本,并验证了这一指标的有效性。本文发现,第一,中国各省份心理资本存在显著的地区异质性分布特征;第二,这种异质性对于理解不同省份不平衡发展非常重要,它广泛解释了各省份在健康、幸福感和行为等方面的差异。本文为心理资本的地区异质性提供了理论解释和工具支持,为未来研究探究心理特质地区异质性的形成及其影响提供了研究思路和参考,有助于推动心理资本理论和心理特质的地区差异理论的相关研究。

Regulation of the density distribution of a strongly dissipative plasma by a pulsed magnetic field

A pulsed transverse magnetic field with pulse width of 12 ms and magnitude of 2 T was used to modify the density distribution of a weakly-ionized plasma flow with strong collisions between the charged particles and neutrals.The morphology of the plasma is changed substantially,with the density increased upstream and decreased downstream.Meanwhile,the plasma toward the axis contracts laterally and gradually converges to a collimated flow.In addition,a drift wave is observed to be excited in the inhomogeneous plasma by the magnetic field.

Keratocyst Odontogenic Tumor (KCOT): Treatment Methods at the Second Affiliated Hospital of Jiamusi University

Many studies have been done about the treatment of KCOT, but the recurrence rate still remains high despite the combination of surgical techniques used, associated with or without the use chemical solutions such as Carnoy’s solution or Cryosurgery. Currently, there is no consensus concerning the therapeutic choice for the KCOT. The purpose of this study was to evaluate the different treatment methods used for the management of KCOT in the Second Affiliated Hospital of Jiamusi University and the results obtained from those treatment methods. Settings and Design: Clinical study was done at the Second Affiliated Hospital of Jiamusi University. Materials and Methods: Analytical retrospective review of 63 cases treated surgically from 2009 to 2015 at the Maxillofacial and Oral Surgery Department of the Second Affiliated Hospital of Jiamusi University. All cases diagnosed as KCOT and registered in the archives were used. The level of statistical significance was set at P < 0.05. Results: Of the 63 cases, 55.56% were male and 44.44% female. The sex ratio was 1.25 in favor of male and the average age was 42 years. 81% of the lesions were located in the mandible. Of 40 cases treated by enucleation with peripheral ostectomy, curettage and electric cauterization with application of 2% iodine tincture, no recurrence was found. Of 20 cases treated by the same surgical method but without the application of 2% iodine tincture, recurrence was found in 3 cases (4.76%). 3 cases treated by resection had no recurrence. Significant relation between recurrence and type of treatment was found (P < 0.05). Conclusion: In our series, those cases that were treated by combination of surgical methods used with 2% iodine tincture showed an “improvement” in the reduction of recurrence, suggesting a future question to be examined in experimental study is to test the effectiveness of 2% iodine tincture.

Advancements in the mind-machine interface:towards re-establishment of direct cortical control of limb movement in spinal cord injury

Spinal cord injury（SCI）resulting in loss of motor function can be caused by a variety of conditions,ranging from traumatic to neoplastic to infectious.It is estimated that nearly 300,000individuals live with the effects of SCI in the United States alone（National Spinal Cord Injury Statistical Center,2016）.Current treatment modalities for patients suffering from SCI are primarily supportive,

Problems and countermeasures on main mineral resource sustainable supply in northeastern China

northeastern China is an important old industrial base in China. Mineral resources are the foundation of industry development. However, because of long-term exploitation of mineral resources in northeastern China, the mineral resources reserves decrease gradually and some mineral resources are nearly exhausted, which restricts revitalization and sustainable development of the northeast old industrial base. On the basis of the comprehensive analysis of development and utilization status of mineral resources and supply and demand situation of main mineral resources in northeastern China, the authors put forward countermeasures on main mineral resources sustainable supply in northeastern China.