Double low-dose computed tomography (CT) angiography of craniocervical arteries using a test bolus of diluted contrast medium and a personalized contrast protocol.

AIM: To prospectively assess the value of a test bolus of diluted contrast medium (CM) combined with a personalized contrast protocol in craniocervical computed tomography angiography (cc-CTA) with low radiation and CM doses. MATERIALS AND METHODS: Eighty-six consecutive subjects were divided into two groups at random (43 in each one): group A: 100/Sn140 kVp, filtered back-projection reconstruction, iopromide (370 mgI/ml) 50 ml; group B: 80/Sn140 kVp, iterative reconstruction, iodixanol (270 mgI/ml). In group B, the test bolus contained 27 ml of diluted CM, a personalized protocol with low-concentration CM was used for angiography, and the test bolus injection duration in angiography remained the same. Artery values over 200 Hounsfield units were considered significant. RESULTS: Image quality for all cases was found to be diagnostic. No significant differences were found in the arterial densities of the ascending aorta or basilar artery between the groups. The values of the common carotid artery, internal carotid artery, and middle cerebral artery in group B were significantly lower. The effective dose and average iodine uptake were significantly lower in group B. CONCLUSION: With double-low-dose cc-CTA, test bolus scanning based on diluted CM combined with a personalized contrast protocol can yield diagnostic-quality images and significantly reduce the radiation and CM doses.

[Analysis on the characteristics of acute occupational poisoning events in Yunnan, 2004-2019].

Objective: To analyze the epidemiological characteristics of acute occupational poisoning in Yunnan province, so as to provide basis for formulating prevention and control measures of acute occupational poisoning in Yunnan province. Methods: In December 2019, the information of acute occupational poisoning events reported in Yunnan province from 2004 to 2019 was collected, and the epidemiological distribution, event classification, industry characteristics, poison types and poisoning causes were analyzed. Results: A total of 47 acute occupational poisoning incidents were reported in Yunnan province from 2004 to 2019, with 562 poisoning cases and 51 deaths (case fatality rate of 9.07%) . The regions with the largest number of reported incidents were Kunming and Qujing, with 12 incidents (25.53%) and 10 incidents (21.28%) respectively; The majority of incidents was relatively large (31 incidents, 65.96%) , and the industry was mainly distributed in the chemical industry (19 incidents, 40.43%) and metallurgy (15 incidents, 31.91%) . The most poisonous poisons were carbon monoxide (10 incidents, 21.28%) and arsine (9 incidents, 19.15%) . The main causes of poisoning included not using personal protective equipment or poor equipment (25 incidents, 53.19%) , failure to formulate or violate safety operating procedures (15 incidents, 31.91%) . Conclusion: Acute occupational poisoning incidents occur from time to time in Yunnan province, and the fatality rate is high. Therefore, it is necessary to strengthen the supervision of key areas and industries.

[Effects of preoperative segmental mobility on the clinical and radiographic outcomes following one-level artificial cervical disc replacement].

Objective: To investigate the effects of preoperative segmental range of motion (ROM) on clinical and radiographical outcomes after artificial cervical disc replacement (ACDR) and explore whether ACDR could be indicated for patients with preoperative limited or excessive segmental ROM. Methods: From January 2008 to December 2017, patients who underwent Prestige-LP ACDR in West China Hospital were retrospectively reviewed. The preoperative and postoperative X-rays of the cervical spine were collected to measure the radiographic parameters, including cervical lordosis (CL), C(2-7) ROM, disc height (DH), disc angle (DA) and ROM at the arthroplasty level. Clinical outcomes were evaluated using the Japanese Orthopedic Association (JOA) and the Neck Disability Index (NDI) scores. The correlation between preoperative segmental ROM and postoperative clinical and radiographical outcomes were also analyzed. Results: A total of 161 patients were analyzed, with 73 males and 88 females. The mean age was (44±8) years, and the follow-up period was 34 months (12-120 months). JOA and NDI scores improved after ACDR (P<0.05). However, postoperative C(2-7) ROM and ROM at the arthroplasty level were comparable with preoperative counterparts (both P>0.05). Preoperative segmental ROM positively correlated with C(2-7) ROM and ROM at the arthroplasty segment (r=0.213、0.271, both P<0.05), but was negatively correlated with the change of ROM (r=-0.534, P<0.05). The segmental ROM was 4.0°±1.0° in the limited-ROM group (A) and 14.6°±1.3° in the excessive-ROM group (B), respectively. There were significantly more patients diagnosed with cervical spondylosis in group A than in group B (35.5% vs 10.7%, P<0.05). The level-distribution was statistically different between the two groups. C(5/6) and C(6/7) were prone to limited motion in group A, while C(4/5) and C(5/6) were predisposed to excessive motion in group B (all P<0.05). After surgery, C(2-7) ROM increased for 14.2°±16.8° in group A, while paradoxically decreased for 2.2°±14.4° in group B. However, C(2-7) ROM in group B was still larger than that in group A (P<0.05). Similarly, the ROM at the arthroplasty level increased by 3.1°±3.7° in group A, whereas the values decreased by 4.4°±4.2° in group B postoperatively. In addition, group A still had less segmental ROM than group B (P<0.05). The preoperative DH in group A was less than that in group B (P<0.05). The rates of ASD, HO, and high-grade HO in group A were all higher than those in group B but without significant differences (all P>0.05). Conclusion: Preoperative segmental ROM has no significant effects on clinical outcomes after ACDR; it has a positive correlation with postoperative global and segmental ROM while is negatively correlated with ROM change.

Population structure analysis and association mapping of blast resistance in indica rice (Oryza sativa L.) landraces.

Rice blast caused by Magnaporthe oryzae is one of the most devastating rice diseases worldwide. To understand the genetic diversity of indica landrace accessions and identify simple sequence repeat (SSR) markers that are associated with blast resistance, a population of 276 indica landraces from across the world was constructed. This population was then used to evaluate the blast-resistance phenotype through artificial inoculation under controlled conditions in 2012 and 2013. The genetic diversity and association of the population with resistance were analyzed by examining the phenotype for 160 SSR markers distributed on 12 rice chromosomes. The 276 accessions were classified into seven groups using model- and distance-based cluster analyses. Associations between SSR markers and blast resistance showed that 26 SSR markers were significantly associated with blast resistance in 2012 and 2013 (P < 0.01) and that the phenotypic variation ranged from 2.68 to 13.11%. Nineteen of the markers associated with blast resistance were located in regions where genes or quantitative trait loci (QTLs) have been previously reported, and seven were newly identified in this study. These results indicate that marker-trait association has potential advantages over classical linkage analysis and QTL mapping, and that these markers could be used for marker-assisted selection in rice blast-resistance-breeding programs.

Correlation-induced self-doping in the iron-pnictide superconductor Ba2Ti2Fe2As4O.

The electronic structure of the iron-based superconductor Ba2Ti2Fe2As4O (Tc(onset)=23.5 K) has been investigated by using angle-resolved photoemission spectroscopy and combined local density approximation and dynamical mean field theory calculations. The electronic states near the Fermi level are dominated by both the Fe 3d and Ti 3d orbitals, indicating that the spacer layers separating different FeAs layers are also metallic. By counting the enclosed volumes of the Fermi surface sheets, we observe a large self-doping effect; i.e., 0.25 electrons per unit cell are transferred from the FeAs layer to the Ti2As2O layer, leaving the FeAs layer in a hole-doped state. This exotic behavior is successfully reproduced by our dynamical mean field calculations, in which the self-doping effect is attributed to the electronic correlations in the 3d shells. Our work provides an alternative route of effective doping without element substitution for iron-based superconductors.

Short communication: high insulin concentrations inhibit fatty acid oxidation-related gene expression in calf hepatocytes cultured in vitro.

In dairy cows, ketosis is an important disease associated with negative energy balance, which leads to low blood glucose levels and high blood nonesterified fatty acid levels. The liver is the most active organ in cows for the metabolism of nonesterified fatty acids. Insulin is an anabolic hormone that plays numerous roles in the metabolism of carbohydrates, lipids, and proteins, as well as being a potent regulator of fatty acid oxidation. In this study, using fluorescent quantitative reverse-transcription PCR, ELISA, and primary hepatocytes cultured in vitro, we examined the effect of insulin (0, 5, 10, 20, 50, and 100 nmol/L) on fatty acid oxidation by monitoring mRNA and protein expression levels of key enzymes: long-chain acyl-coenzyme A synthetase, carnitine palmitoyltransferase I, and long-chain acyl-coenzyme A dehydrogenase. The results showed that the mRNA and protein expression of long-chain acyl-coenzyme A synthetase, carnitine palmitoyltransferase I, and long-chain acyl-coenzyme A dehydrogenase was markedly decreased when the concentration of insulin in the media was increased. These findings indicate that high levels of insulin significantly inhibit the expression of genes related to fatty acid oxidation and consequently results in a decreased level of fatty acid oxidation in calf hepatocytes.

Three dimensionality and orbital characters of the Fermi surface in (Tl,Rb)(y)Fe(2-x)Se2.

We report a comprehensive angle-resolved photoemission spectroscopy study of the tridimensional electronic bands in the recently discovered Fe selenide superconductor ((Tl,Rb)(y)Fe(2-x)Se2 (T(c)=32 K). We determined the orbital characters and the k(z) dependence of the low energy electronic structure by tuning the polarization and the energy of the incident photons. We observed a small 3D electron Fermi surface pocket near the Brillouin zone center and a 2D like electron Fermi surface pocket near the zone boundary. The photon energy dependence, the polarization analysis and the local-density approximation calculations suggest a significant contribution from the Se 4p(z) and Fe 3d(xy) orbitals to the small electron pocket. We argue that the emergence of Se 4p(z) states might be the cause of the different magnetic properties between Fe chalcogenides and Fe pnictides.

Unconventional anisotropic s-wave superconducting gaps of the LiFeAs iron-pnictide superconductor.

We have performed high-resolution angle-resolved photoemission spectroscopy on Fe-based superconductor LiFeAs (T(c)=18 K). We reveal multiple nodeless superconducting (SC) gaps with 2Δ/k(B)T(c) ratios varying from 2.8 to 6.4, depending on the Fermi surface (FS). We also succeeded in directly observing a gap anisotropy along the FS with magnitude up to ~30%. The anisotropy is fourfold symmetric with an antiphase between the hole and electron FSs, suggesting complex anisotropic interactions for the SC pairing. The observed momentum dependence of the SC gap offers an excellent opportunity to investigate the underlying pairing mechanism.

77Se NMR study of the pairing symmetry and the spin dynamics in K(y)Fe(2-x)Se2.

We present a 77Se NMR study of the newly discovered iron selenide superconductor K(y)Fe(2-x)Se2, in which T(c) = 32 K. Below T(c), the Knight shift 77K drops sharply with temperature, providing strong evidence for singlet pairing. Above T(c), Korringa-type relaxation indicates Fermi-liquid behavior. Our experimental results set strict constraints on the nature of possible theories for the mechanism of high-T(c) superconductivity in this iron selenide system.

Unusual magnetization process and magnetocaloric effect in α-CoV2O6driven by pulsed magnetic fields.

In low-dimensional Ising spin systems, an interesting observation is the presence of step magnetization at low temperatures. Here we combine both DC and pulsed magnetic fields to study the 1/3 magnetization plateau and multiple steps in the Ising spin-chain material α-CoV2O6. Magnetization in pulsed fields is quite different from that in DC fields, showing multiple steps in an intermediate range of 4.2-6 K, inverted hysteresis below 4.2 K and asymmetric magnetization in negative fields below 11 K. We demonstrate that these unusual behaviors in magnetization are caused by the spin dynamics and the anomalous magnetocaloric effect (MCE) in α-CoV2O6, i.e., abrupt changes of sample temperature in adiabatic conditions. We successfully separate the influence between the intrinsic slow spin dynamics and the quasi-extrinsic temperature change. From the MCE, we find that some irreversible behavior is originated from the slow spin dynamics. Two different slow dynamics associated with the metastable steps are observed: one is sensitive to the slow field sweep rate at the order of ∼mT s-1and weakly depends on temperature, while the other responds to the rapid field sweep rate of ∼kT s-1and dominates at lowest temperature. We also distinguish that the metastable transition atH4is the first order and crucial for the ferrimagnetic to ferromagnetic transition. This study is useful to the understanding of multistep magnetization in α-CoV2O6and sheds light on recent experimental findings of related compounds.

Distal trisomy of 10q with distal monosomy of 15q due to a paternal translocation.

Distal trisomy of 10q is a rare chromosomal abnormality. Distal deletions of the terminal long arm of chromosome 15 have rarely been described. We report on a male infant with low birth weight and microcephaly, a flat face with a spacious forehead, low-set ears, blepharophimosis, microphthalmia, a small nose, and a depressed nasal bridge. Microarray comparative genomic hybridization identified that he had the karyotype 46, XY, der (15) t (10;15) (q25.2;q26.2) pat, with chromosomal breakpoints at 10q25.2 and 15q26.2. This male neonatal case had an unbalanced translocation inherited from his father who was a balanced carrier with the karyotype 46, XY, t (10;15) (q25;q26). The neonate had a partial trisomy of the long arm of chromosome 10 with a partial monosomy of distal 15q. The clinical features were in agreement with previous descriptions and allowed us to propose a growth retardation phenotype for this neonate case.

Development of an assay for rapid identification of meat from yak and cattle using polymerase chain reaction technique.

Yak meat is of good quality with fine texture, high protein and low fat content, and rich in amino acids compared with that of cattle, and it lacks anabolic steroids or other drugs. In general terms, however, the meat yield of yak is relatively low compared with that of the cattle. In order to prevent possible adulteration of yak meat with cattle meat, based on the sequence of mitochondrial 12S rRNA gene, a multiplex PCR-based approach was proposed for rapid identification of the meat from yak and cattle using three primers designed in this work. Through the combinatorial usage of three primers with a single reaction set, two fragments of 290 and 159bp were amplified from the cattle meat DNA, whereas only a fragment of 290bp was obtained from the yak meat DNA. Using the assay described, satisfactory amplification was accomplished in the analysis of raw and heat-treated binary meat mixtures of yak/cattle with a detection limit of 0.1% for cattle meat. The technique is fast and straightforward. It might be a useful tool in the quality control of yak meat and meat products.

[Epidemiological characteristics of imported acute infectious diseases in the border areas of Yunnan province, 2008-2017].

Objective: To understand the epidemiological characteristics of imported acute infectious diseases between 2008 and 2017 in the border areas of Yunnan province. Methods: All the cases occurred between January 2008 and December 2017 and related information was from the Chinese CDC infectious disease report information management system, according to definition of imported cases diagnosed by clinicians. Epidemiological characteristics of the imported cases of related information were gathered. Results: A total of 13 157 imported acute infectious diseases were reported from the border areas of Yunnan province, which accounted for 6.03% (13 157/218 284) of the total number of acute infectious diseases in the same areas from 2008 to 2017. Malaria, dengue fever and hand-foot-mouth disease were accounted for 56.05% (7 374/13 157), 21.82% (2 871/13 157) and 4.62% (608/13 157), of all the case, respectively. The number of imported malaria cases decreased annually. However, dengue fever showed a sharp increase. Peaks of the epidemics appeared as: May for malaria and October for dengue fever. Male patients were accounting for the majority (73.22%, 9 634/13 157), so as the patients with Chinese nationality (54.91%, 7 225/13 157). The age distribution appeared as: 67.12% (8 829/13 157) for the 15-44 year olds and 19.26% (2 535/13 157) were children below 14 years of age. Proportions of occupation appeared as: farmers (45.23%, 5 596/13 157), migrant workers (21.30%, 2 802/13 157) and children living at home (11.12%, 1 463/13 157). Most of the imported cases were coming from Myanmar and appearing in the following three counties: Ruili city, Tengchong city, and Yingjiang of Yunnan province. Cities/counties that with number of imported cases more than 10% of the local reported cases, would include Ruili city, Tengchong city, Zhenkang county and Mangshi of Yunnan province. Conclusions: Imported acute infectious disease was a serious public health problem in Yunnan province, 2008-2017. The main imported acute infectious diseases were malaria, dengue fever and hand-foot-mouth disease. The majority imported cases were accounting for Chinese, male, young adults and farmers. It is also important for immigration workers to carry out surveillance, prevention and control programs on infectious diseases when working in neighboring countries.

Adsorption of ethylenediaminetetraacetic dianhydride modified oxalate decarboxylase on calcium oxalate.

We used ethylenediaminetetraacetic acid dianhydride (EDTAD) to modify oxalate decarboxylase (OXDC) to improve its adsorption on calcium oxalate stones. The modified sites were identified by Ultra performance liquid chromatography-mass spectrometry (UPLC-MS) and the adsorption mechanism of the EDTAD-modified OXDC on calcium oxalate (CaOx) was investigated. We investigated adsorption time, initial enzyme concentration, temperature and solution pH on the adsorption process. Data were analyzed using kinetics, thermodynamics and isotherm adsorption models. UPLC-MS showed that EDTAD was attached to OXDC covalently and suggested that the chemical modification occurred at both the free amino of the side chain and the α-NH2 of the peptide. The adsorption capacity of the EDTAD-OXDC on calcium oxalate was 53.37% greater than that of OXDC at the initial enzyme concentration of 5 mg/ml, pH = 7.0, at 37° C. The modified enzyme (EDTAD-OXDC) demonstrated improved oxalate degradation activity at pH 4.5-6.0. Kinetic data fitting analysis suggested a pseudo second order kinetic model. Estimates of the thermodynamic parameters including ΔG0, ΔH0 and ΔS0 of the adsorption process showed it to be feasible, spontaneous and endothermic. Isotherm data fitting analysis indicated that the adsorption process is reduced to monolayer adsorption at a low enzyme concentration and to multilayer adsorption at a high enzyme concentration. It may be possible to apply OXDC to degradation of calcium oxalate stones.

[Effects of CD34(+) selected stem cells for the treatment of poor graft function after allogeneic stem cell transplantation].

Objective: To evaluate the efficacy and safety of purified CD34(+) stem cell boost in the treatment of poor graft function (PGF) after allogeneic hematopoietic stem cell transplantation (HSCT) . Methods: 12 patients with poor graft function, reported in our hospital during January 2014 to March 2018, were retrospectively analyzed; The donors of 12 patients were HLA mismatched family members, and all treated with donor purified CD34(+) stem cell after G-CSF mobilization, calculating and statistical analyzing the purity of separation and the recovery rate of CD34(+) stem cells. The related complications and the recovery of blood cells after infusion were observed. Results: The purity of CD34(+) cells in the separation products was 92.0% (44.0%-97.0%) , and the recovery rate was 55.0% (45.0%-96.7%) . The median number of CD34(+) cells was 1.9 (0.9-4.4) ×10(6)/kg with CD3(+) cells as 0.6 (0.3-2.0) ×10(4)/kg. The median durations of white blood cells, platelet and red blood cells recoveries were 18 (14-39) , 29 (16-153) and 60 (9-124) days, respectively. All 12 patients didn't experience serious adverse reactions in the process of infusion, 10 patients achieved hematopoietic recovery, 1 case partial remission, 1 case no recovery, without occurrence of aggravated infection, graft versus host disease and other complications. Conclusion: The infusion of donor purified CD34(+) stem cell was a safe and effective method for PGF after allogeneic HSCT.

Microsurgery for ruptured cerebellar arteriovenous malformations.

OBJECTIVE: To summarize the clinical features of ruptured cerebellar arteriovenous malformations (AVMs) and to explore surgical methods and outcomes in ruptured cerebellar AVM patients. PATIENTS AND METHODS: In the past 14 years, 67 patients with cerebellar AVMs were treated at our institution, accounting for 14.9% of the total vascular malformation patients in our department. In this study, we retrospectively analyzed the clinical characteristics, operation indication, surgery techniques, and prognoses of these cases. RESULTS: Among the 67 AVM cases, the distribution of Spetzler-Martin grades was 32 Grade I, 14 Grade II, 13 Grade III, 5 Grade IV, and 3 Grade V cases. Microsurgical treatment was carried out via the retrosigmoid approach or suboccipital midline approach. After the surgery, the distribution of GOS grades was 60 Grade V, 3 Grade IV, 1 Grade III, 2 Grade II, and 2 Grade I cases. CONCLUSIONS: Microsurgical removal should be performed in ruptured cerebellar AVM patients as early as possible once the preoperative and postoperative preparations were done. Good surgical effects were obtained by using proper surgery techniques and the right protection of critical cerebral structures. Patients with a GCS grade of ≥ 8 showed good recovery, but patients with a grade of < 8 had poor prognoses.

Destruction of halogenated hydrocarbons with solvated electrons in the presence of water.

Model halogenated aromatic and aliphatic hydrocarbons and halogenated phenols were dehalogenated in seconds by solvated electrons generated from sodium in both anhydrous liquid ammonia and ammonia/water solutions. The minimum sodium required to completely dehalogenate these model compounds was determined by increasing the Na/substrate ratio until halogen loss was complete. Minimum sodium consumptions were determined in both anhydrous liquid ammonia and with a (5, 20, 50-fold molar excess of water per mole of halide). While more Na was consumed in the presence of water, these dehalogenations were still efficient when a 50-fold water excess was present. Dehalogenation is faster than competiting reactions with water. CCl4 and CH3CCl3 in the presence of a stoichiometric deficiency of sodium produced only CH4 and CH3CH3 and recovered CCl4 or CH3CCl3, respectively. No partially dechlorinated products were detected, indicating dechlorination was diffusion controlled. Na consumption per chlorine removed (as NaCl) was lower than that of Li, K or Ca and this advantage increased in the presence of water. Na consumption was lower using Na chunks instead of a thin Na mirror. Chloroaromatic compounds gave the parent aromatic hydrocarbon and aminated products in anhydrous ammonia but aminated products did not form when water was present.

[Protective effects of ginsenosides in myocardial ischemia and reperfusion injury].

To verify whether ginsenosides will attenuate the myocardial ischemia and reperfusion injury, the left anterior descending coronary artery (LAD) was snared for 2 hours in 23 dogs and then the ischemic myocardium was reperfused. 45 minutes after ischemia, the animals were randomly divided into a ginsenosides group (n = 11, receiving a slow IV bolus of ginsenosides 10 mg/kg and then a continuous infusion of 80 micrograms/kg/min) and a saline solution group (n = 12 receiving equal amount of glucose in saline). The treatment was started 45 minutes after coronary occlusion and stopped one hour after reperfusion. 24 hours later, the dogs were killed and the extent of myocardial necrosis was determined histologically. The LVEDP, arterial pressure and heart rate were markedly lower in the ginsenosides group. Electrocardiographic findings of myocardial ischemia were significantly improved in the ginsenosides group. 8 controls developed malignant arrhythmia after reperfusion, but none in ginsenosides group. The myocardial ultrastructure can be protected by ginsenosides during the period of ischemia and reperfusion. The infarct size in saline group was 22.7 +/- 3.2% while in the ginsenosides group it was 5.2 +/- 1.3% (P less than 0.05). These results show that ginsenosides can protect the ischemic myocardium and reperfusion injury of myocardium.

[Determination of flecainide concentration in blood plasma by HPLC and pharmacokinetic parameters in volunteers].

A high performance liquid chromatographic method (ultraviolet detection) for the determination of flecainide concentration in human plasma was reported. Flurazepam (dalmadorm) was used as the internal standard. A mixture of methanol and deionized water containing ion paired reagent served as the mobile phase. The regression equation of flecainide was: y = 0.0017x + 0.0131, r = 0.9975. The extraction recoveries exceeded 94%, and the coefficients of variation (both within the same day and in different days) were less than 5%. The pharmacokinetic parameters in Chinese volunteers after taking flecainide were: Ka = 0.908h-1, T1/2 = 8.131h, peats time = 3.487h, AUC = 441.8ng.h/ml. The mean plasma concentration of flecainide in cases responded well to this drug was 423.6 +/- 227.4ng/ml.