Dynamics of the Deformable Fluid Interface Interacting with an Approaching Solid under the Electrostatic Field

A theoretical model was developed to describe the dynamics of a deformable fluid interface interacting with an approaching solid without contact by both the attractive electrostatic and van der Waals (i.e., vdW) interaction, analogous to the situation in the experiments by electric force microscopy (i.e., EFM) or electric-surface force apparatus (i.e., E-SFA) involved in the soft fluid interface. On the basis of this model, a numerical study of the deformation of the fluid interface, the force-vs-separation behavior, and the critical limiting conditions of contact has systematically been carried out. Our results show that the surface pressure induced by the electrostatic interaction plays a more prominent role in the deformation of the fluid interface than the vdW interaction does, and there exists a principal length scale associated with the relative strength of the electrostatic field to the surface tension, affecting the fluid interface shape under the electrostatic field. It was also shown that both the force-distance curves and the corresponding curves of fluid interface deformation peak versus distance for various electrostatic fields satisfy the universal scaling power law. Moreover, an analytical solution to the Euler-Lagrange differential equation governing the deformation of the fluid interface under the external electric field is obtained, and two extended formulas for explicitly describing the principal length scales that respectively characterize the lateral and longitudinal deformations of the fluid interface were determined.

[Interventional strategies and perioperative complications of chronic total coronary occlusion in combination with bifurcation lesions]

Objective: To analyze the clinical characteristics of chronic total coronary occlusion (CTO) combined with bifurcation lesions and the features of coronary intervention and perioperative complications. Methods: This study adopted retrospective cross-sectional research methods and included 673 patients who underwent interventional therapy for chronic total occlusion in Beijing Anzhen Hospital. According to whether there were side branches (diameter ≥2 mm) within 5 mm before and after the CTO occlusion segment, patients were divided into bifurcation group (337 cases) and non-bifurcation group (336 cases). The measurement data did not conform to the normal distribution and were represented as M (Q₁, Q₃). The clinical risk factors, coronary angiography characteristics, interventional treatment strategies and perioperative complications were compared between the two groups. Results: The patients in the bifurcation group were 60 (51, 65) years old, and 86.6% (292 cases) were male; the patients in the non-bifurcation group were 60 (52, 66) years old, and 83.0% (279 cases) were male.Coronary artery disease in all patients was mainly multivessel disease, of which three-vessel disease accounted for 59.9% (403 cases) and double-vessel disease accounted for 25.4% (171 cases).The target vessel in the bifurcation group was predominantly left anterior descending artery (62.3%, 210 cases), and the target vessel in the non-bifurcation group was more common in the right coronary artery (56%, 188 cases). The target vessel diameter was larger in the bifurcation group (2.91(2.71, 3.24) mm vs 2.80(2.55, 3.13) mm, P<0.001). Most patients used the antegrade technique (88%, 592 cases), and the use of antegrade technique in the bifurcation group (91.9%, 307 cases) was higher than that in the non-bifurcation group (84.8%, 285 cases) (P=0.012). After CTO-PCI, 72.8% (490 cases) of patients achieved successful angiography. A total of 73 patients (10.8%) had perioperative complications, and there was no statistical difference between the two groups. However, the incidence of perioperative myocardial infarction was higher in the bifurcation group (5.9%, 20 cases) than non-bifurcation group (2.7%, 9 cases) (P=0.038). Conclusions: CTO complicated with bifurcation lesions are very common in clinical practice. Most patients with CTO have multiple coronary artery disease at the same time. The target vessel is more common in the left anterior descending artery, and the diameter of the vessel is larger. It is more common to use antergrade technique, accompanied by more perioperative myocardial infarctions.

Novel Multifunctional Stimuli-Responsive Nanoparticles for Synergetic Chemo-Photothermal Therapy of Tumors

In this study, a novel class of multifunctional responsive nanoparticles is designed and fabricated as drug nanocarriers for synergetic chemo-photothermal therapy of tumors. The proposed nanoparticles are composed of a thermo-/pH-responsive poly(N-isopropylacrylamide-co-acrylic acid) (PNA) nanogel core, a polydopamine (PDA) layer for photothermal conversion, and an outer folic acid (FA) layer as a targeting agent for the folate receptors on tumor cells. The fabricated nanoparticles show good biocompatibility and outstanding photothermal conversion efficiency. The proposed nanoparticles loaded with doxorubicin (DOX) drug molecules are stable under physiological conditions with low leakage of drugs, while rapidly release drugs in environments with low pH conditions and at high temperature. The experimental results show that the drug release process is mainly governed by Fickian diffusion. In vitro cell experimental results demonstrate that the PNA-DOX@PDA-FA nanoparticles can be phagocytized by 4T1 tumor cells and release drugs in tumor cell acidic environments, and confirm that the combined chemo and photothermal therapeutic efficacy of PNA-DOX@PDA-FA nanoparticles is higher than the photothermal therapeutic efficacy or the chemotherapeutic efficacy alone. The proposed multifunctional responsive nanoparticles in this study provide a novel class of drug nanocarriers as a promising tool for synergetic chemo-photothermal therapy of tumors.

[Effect of high-titer plasma in pediatric patients with severe adenovirus pneumonia]

Objective: To explore the efficacy and safety of high-titer plasma in the treatment of pediatric patients with severe adenovirus pneumonia. Methods: The clinical data of 92 pediatric patients with severe adenovirus pneumonia admitted to pediatric intensive care unit (PICU) in Guangzhou Women and Children's Medical Center from January 2016 to October 2019 were retrospectively collected. According to the treatment with or without high-titer plasma, the patients were divided into plasma treatment group (n=41) and non-plasma treatment group (n=51). The 51 patients with chest radiograph showing more than half the lungs involved were divided into plasma treatment group (n=29) and non-plasma treatment group (n=22). According to fever duration before plasma treatment, patients were divided into early group (≤5 days, n=5), middle group (>5-10 days, n=14), and late group (>10 days, n=22). Baseline data, therapeutic effects, and prognosis of patients in each group were analyzed with t test, non-parametric rank sum test, one-way ANOVA and chi-square test. Results: Ninety-two patients were included. There were no significant differences in age, gender, body weight, fever duration, sequential organ failure assessment, and Murray lung injury score between plasma treatment group and non-plasma treatment group before admission (all P>0.05). The proportion of patients whose temperature drop to normal within 5 days was higher in plasma treatment group than that in non-plasma treatment group (88% (36/41) vs. 69% (35/51), χ(2)=4.745, P=0.029). However, there were no significant differences between the two groups in the proportions of invasive ventilator weaning within 14 days (63% (26/41) vs. 76% (39/51), χ(2)=1.868, P=0.172), transfer out from PICU within 14 days (49% (20/41) vs. 69% (35/51), χ(2)=3.724, P=0.054), discharge within 28 days (51% (21/41) vs. 61%(31/51), χ(2)=0.846, P=0.358) and survived patients (85% (35/41) vs. 76%(39/51), χ(2)=1.143, P=0.285). Among patients with severe chest radiograph, the proportions of patients whose temperature drop to normal within 5 days and survived patients were higher in plasma treatment group than those in non-plasma treatment group (86% (25/29) vs. 59% (13/22), χ(2)=4.843, P=0.028; 83% (24/29) vs. 55%(12/22), χ(2)=4.796, P=0.029, respectively). However, there were no significant differences between the two groups in the proportions of invasive ventilator weaning within 14 days (52% (15/29) vs. 59% (13/22), χ(2)=0.274, P=0.601), transfer out from PICU within 14 days (34% (10/29) vs. 45% (10/22), χ(2)=0.632, P=0.427), and discharge within 28 days (45% (13/29) vs. 45% (10/22), χ(2)=0.002, P=0.964). Among early, middle and late group, the proportions of invasive ventilator weaning within 14 days were 2/5, 13/14 and 50% (11/22), respectively, with statistically significant difference (χ(2)=8.119, P=0.017). There were no significant differences in the proportions of patients whose temperature drop to normal within 5 days (4/5, 14/14, 82% (18/22), χ(2)=2.965, P=0.227), transfer out from PICU within 14 days (2/5, 10/14, 36%(8/22), χ(2)=4.386, P=0.112), discharge within 28 days (2/5, 8/14, 50% (11/22), χ(2)=0.462, P=0.794) and survived patients (4/5, 13/14, 82% (18/22), χ(2)=0.966, P=0.617) in the three groups. Only one case with high-titer plasma therapy had rash in the course of infusing plasma and no other adverse reactions were observed. Conclusions: High-titer plasma can shorten the fever time and improve the proportion of survival patients in pediatric severe adenovirus pneumonia. The clinical effect of high-titer plasma is better in 5-10 days of fever course. High-titer plasma is an effective and safe treatment.

[Resting metabolic rate estimated by bioelectrical impedance analysis and its determinants in maintenance hemodialysis patients]

Objective: To explore the level of resting energy expenditure (REE) estimated by bioelectrical impedance analysis and the association of resting metabolic rate (RMR) with clinical related factors, and provide new ideas for improving protein energy wasting (PEW) in maintenance hemodialysis (MHD) patients. Methods: Seven hundred and sixty-five subjects receiving MHD between July 2015 and September 2016 in 11 hemodialysis centers in Guizhou province were enrolled in this cross-sectional study. Bioelectrical impedance analysis was used to measure RMR and body composition, such as lean body mass, fat mass and body cell mass (BCM). Baseline characteristics, routine blood test indexes and biochemical data of hemodialysis patients were collected. The level of RMR and body composition in hemodialysis patients was compared by gender grouping. Then the patients were divided into four groups according to the cutoff value of RMR quartile. Spearman correlation analysis and multiple linear regression analysis were used to analyze the relationships between RMR and clinical related factors. Results: The average age of MHD patients was (54.96±15.78) years and the duriation of dialysis was (42.3±9.0) months. The level of RMR in male patients (474 cases, 61.96%) was significantly higher than that in female patients [1 591(1 444, 1 764) kcal/d vs 1 226 (1 104, 1 354) kcal/d, P<0.001]. However, this significant difference of RMR between different genders disappeared after adjusting for lean body mass (P=0.193). Multiple linear regression analysis showed that RMR was positively correlated with body surface area (β=0.817) and lactate dehydrogenase (LDH) (β=0.198), and negatively correlated with age (β=-0.141), all P<0.05. Conclusion: RMR levels in patients with maintenance hemodialysis are associated with lactate dehydrogenase level, which may become a new index to evaluate energy consumption.

A Simple Device Based on Smart Hollow Microgels for Facile Detection of Trace Lead(II) Ions

A simple device, which is equipped with a non-woven fabric filter medium immobilized with ion-recognizable smart hollow microgels, is developed for facile detection of trace lead(II) ions (Pb²⁺ ). The ion-recognizable smart microgels are made of poly(N-isopropylacrylamide-co-benzo-18-crown-6-acrylamide) (PNB), in which the 18-crown-6 groups act as the sensors of Pb²⁺ and the N-isopropylacrylamide groups act as the actuators. The PNB hollow microgels can isothermally change from a shrunk state to a swollen state in response to recognizing Pb²⁺ in the aqueous environment due to the electrostatic repulsion among the charged 18-crown-6/Pb²⁺ complex groups and the enhancement of hydrophilicity of the microgels. Due to the hollow structures, the PNB microgels show remarkable isothermal swelling ratio. Thus, the flux of solution pass through the non-woven fabric filter medium decreases significantly because of the remarkable reduction in the space for liquid flowing upon recognizing Pb²⁺ . The Pb²⁺ concentration can be detected quantitatively by simply and easily measuring the change of solution flux using the proposed device, which is operated without external power supply or spectroscopic measurements. The strategy proposed in this study provides a promising method for facile detection of trace Pb²⁺ in aqueous environments.

The effect of soy isoflavone on bone mineral density in postmenopausal Taiwanese women with bone loss: a 2-year randomized double-blind placebo-controlled study

The treatment of 300-mg/day isoflavones (aglycone equivalents) (172.5 mg genistein + 127.5 mg daidzein) for 2 years failed to prevent lumbar spine and total proximal femur bone mineral density (BMD) from declining as compared with the placebo group in a randomized, double-blind, two-arm designed study enrolling 431 postmenopausal women 45-65 years old.

INTRODUCTION

This study evaluated the effects of soy isoflavones on bone metabolism in postmenopausal women.

METHODS

Four hundred and thirty-one women, aged 45-65 years, orally consumed 300-mg/day isoflavones (aglycone equivalents) or a placebo for 2 years in a parallel group, randomized, double-blind, two-arm study. Each participant also ingested 600 mg of calcium and 125 IU of vitamin D(3) per day. The BMD of the lumbar spine and total proximal femur were measured using dual-energy X-ray absorptiometry at baseline and every half-year thereafter. Serum bone-specific alkaline phosphatase, urinary N-telopeptide of type 1 collagen/creatinine, and other safety assessments were examined regularly.

RESULTS

Two hundred out of 217 subjects in the isoflavone group and 199 out of 214 cases in placebo group completed the treatment. Serum concentrations of isoflavone metabolites, genistein and daidzein, of the intervention group were remarkably elevated following intake of isoflavones (p < 0.001). However, differences in the mean percentage changes of BMD throughout the treatment period were not statistically significant (lumbar spine, p = 0.42; total femur, p = 0.39) between the isoflavone and placebo groups, according to the generalized estimating equation (GEE) method. A significant time trend of bone loss was observed at both sites as assessed by the GEE method following repeated measurement of BMD (p < 0.001). Differences in bone marker levels were not significant between the two treatment groups.

CONCLUSION

Treatment with 300-mg/day isoflavones (aglycone equivalents) failed to prevent a decline in BMD in the lumbar spine or total femur compared with the placebo group.

Morphology-controlled synthesis and a comparative study of the physical properties of SnO2 nanostructures: from ultrathin nanowires to ultrawide nanobelts

Controlled synthesis of one-dimensional materials, such as nanowires and nanobelts, is of vital importance for achieving the desired properties and fabricating functional devices. We report a systematic investigation of the vapor transport growth of one-dimensional SnO(2) nanostructures, aiming to achieve precise morphology control. SnO(2) nanowires are obtained when SnO(2) mixed with graphite is used as the source material; adding TiO(2) into the source reliably leads to the formation of nanobelts. Ti-induced modification of crystal surface energy is proposed to be the origin of the morphology change. In addition, control of the lateral dimensions of both SnO(2) nanowires (from approximately 15 to approximately 115 nm in diameter) and nanobelts (from approximately 30 nm to approximately 2 microm in width) is achieved by adjusting the growth conditions. The physical properties of SnO(2) nanowires and nanobelts are further characterized and compared using room temperature photoluminescence, resonant Raman scattering, and field emission measurements.

Location and phylogenetic analysis of the region immediately upstream of the granulin gene of the Clostera anachoreta granulovirus

The region immediately upstream of the granulin gene from Clostera anachoreta granulovirus (ClanGV) was identified from hybridization experiments and sequenced. The sequence of 5122nt EcoRI restriction fragment was presented and compared with the equivalent area in other GVs. Database searches showed that this region contained three open reading frames (ORFs) similar to the baculovirus genes (egt, fgf and me53, respectively) and four ORFs unique to ClanGV genome. Phylogenetic trees of the baculovirus genes egt and me53 were constructed. These analyses indicated that ClanGV genes may be more closely related to CfGV, CpGV, ClGV, PoGV and AoGV than to PxGV and XcGV.

Characterization and partial genome sequence analysis of Clostera anachoreta granulovirus

The morphological and biological properties as well as partial genomic sequencing of a granulovirus isolated from Clostera anachoreta (Lepidoptera: Notodontidae), C. anachoreta granulovirus (ClanGV), were carried out. The ovoidal occlusion bodies were 337 nm x 170 nm in size, and each granule contained one single rod-shape virion, with a mean size of 250 nm x 46 nm. Granulin had a molecular weight of approximately 30 kDa. ClanGV genome size was estimated as 104.34 kb based on the restriction fragments. The restriction pattern of the ClanGV genome was different from other GVs. A restriction fragment genomic library of ClanGV genome was constructed. The library consisted of nine SalI fragments, seven HindIII fragments and seven EcoRI fragments. One 4.8 kb fragment of the genome, digested by SalI, was sequenced and analyzed. This region was composed of eight unknown ORFs, two baculoviruses homologous gene (vp1054 and lef10) and partial sequence of lef-8. The unknown ORFs included three unique to ClanGV, the other five ORFs were related to baculoviruses. The ORFs, located within this restriction fragment, were compared to homologues in other GVs. The results indicated that ClanGV, CpGV, ClGV, AoGV and PoGV had similar arrangement and orientation of the homologous ORFs. Phylogenetic analysis of VP1054 proteins from 20 baculoviruses indicated that ClanGV was more closely related to CpGV, ClGV, AoGV and PoGV than to other baculoviruses.

Characterization of the RNA-binding domain in the Dendrolimus punctatus cytoplasmic polyhedrosis virus nonstructural protein p44

Dendrolimus punctatus cytoplasmic polyhedrosis virus (DpCPV-1) belongs to the Cypovirus genus in the Reoviridae family. The ORF of genome segment 8 (S8) of DpCPV-1 was cloned into vector pMAL-c2X and used to express a 44kDa protein (p44) in E. coli, which was detected by Western blotting. The gel mobility shift assays showed that p44 had ssRNA-binding activity. Competitive assay indicated that this protein only bind to ssRNA and could not interact with DNA and dsRNA. The binding of p44 to ssRNA is sequence non-specific. To identify the domain(s) important for RNA binding of the protein, a number of deletions were made. These truncated proteins were expressed in E. coli and purified. The affinity of each truncated protein towards ssRNA was then assayed by electrophoretic mobility shift assays and northwestern blot. The results indicated that glutamic acid-rich domain in the central region of p44 from residues 104 to 201 was the ssRNA-binding domain.

Mapping the RNA-binding domain on the DpCPV VP4

The RNA-binding properties of VP4 protein of Dendrolimus punctatus cytoplasmic polyhedrosis virus (DpCPV) VP4 were analyzed. VP4 was expressed in E. coli and assayed for RNA binding activity by gel mobility shift assay. VP4 was found to bind RNA (ssRNA and dsRNA) in a sequence-independent manner, but did not interact with DNA. To identify the domain(s) of the protein important for RNA binding, a number of deletions were made and tested by gel mobility shift assays and northwestern blot. The central region of VP4 from amino acid residues 77 to 155 was found to contain the RNA binding domain.

Nucleotide sequences of genome segments S6, S7 and S10 of Dendrolimus punctatus cypovirus 1

The nucleotide sequences of genome segments S6, S7 and S10 of Dendrolimus punctatus cypovirus 1 Hunan I (DpCPV-HN(I)) and DpCPV-HN(I)-Se(3) (DpCPV-HN(I) passed three times in Spodoptera exigua) were determined. Segment S10 was 944 nucleotides in length and encoded a polyhedrin of 248 amino acids (28,439 Da). Only two nucleotide mutations were found between DpCPV-HN(I) S10 and DpCPV-HN(I)-Se3 S10, and the deduced amino acid sequences of the polyhedrin proteins were identical. Segment S7, 1 501 nucleotides, encoded a protein of 448 amino acids ( approximately 50 kDa; p50). Thirty-one nucleotide mutations were found between DpCPV-HN(I) S7 and DpCPV-HN(I)-Se3 S7, but these resulted in only four amino acid changes. DpCPV-HN(I) S6 encoded a protein of 561 amino acids (63,688 Da; p64). The amino acid sequence of p64, had a high leucine content (10%), and contained a leucine zipper motif and one ATP/GTP-binding site motif.

Genomic sequence analyses of segments 1 to 6 of Dendrolimus punctatus cytoplasmic polyhedrosis virus

The complete nucleotide sequences of genomic segments S1 to S6 from Dendrolimus punctatus cypovirus 1 (DpCPV-1) have been determined. Each segment of S1 to S6 possess a single open reading frame. Conserved motifs 5' (AGUAA) and 3'(GUUAGCC) were found at the ends of each segment. Comparison of the proteins of DpCPV with those of other members in the family Reoviridae lead us to suggest that S1, S3, S4 and S6 encode the viral structural protein VP1, VP2, VP3 and VP4, respectively. S5 encoded viral non-structural protein p100 and S2 encodes an RNA-dependent RNA polymerase (RdRp). Motif analysis shows that VP3 is similar to the methyltransferase of Methanosarcina mazei Goe1, VP4 has motifs for leucine zipper and ATP/GTP-binding sites, and p100 is remarkably similar to foot-and-mouth disease virus 2A protease (FMDV 2Apro). Phylogenetic analysis of RdRps from nine viruses of the family Reoviridae indicates that DpCPV is a type 1 cypovirus, more related to Bombyx mori cypovirus (BmCPV) than to other cypovirus species. DpCPV is more related to Rice ragged stunt virus (RRSV) than to other members of different genera of the family Reoviridae, which seems to confirm the previous hypothesis that plant reoviruses originated from insect reoviruses.

Molecular characterization of segments 7-10 of Dendrolimus punctatus cytoplasmic polyhedrosis virus provides the complete genome

The nucleotide sequences of genomic segments S7-S10 from Dendrolimus punctatus cypovirus strain Hunan (DpCPV-Hn) have been determined. This provides the complete genome sequences of DpCPV-Hn. Each segment of S7-S10 possess a single segment each. Homology searches showed that the nucleotide sequences and the deduced amino acid sequences of DpCPV S7-10 had high level of identities with those of Bombyx mori cypovirus (BmCPV) S7-10, respectively. While the amino acid sequences of the proteins encoded by DpCPV S7 and S8 have low identities with those of the proteins encoded by type 14 Lymantria dispar cypovirus S7 and S8, respectively. DpCPV S7 encodes viral structural protein VP5, S8 and S9 encode viral non-structural proteins, and S10 encodes polyhedrin gene, according to the function of the genome segments of BmCPV. There are glutamic-acid-rich and proline-rich domains in the central region of DpCPV S8 encoded protein. A nuclear localization signal was found in the protein encoded by DpCPV S9. Phylogenetic analysis of RNA-dependent RNA polymerases from nine viruses of the family Reoviridae and polyhedrin from eight viruses of the genus Cypovirus indicate that DpCPV is a type 1 cypovirus, more closely related to BmCPV than to other cypovirus species. These results also support the classification of CPV groups based on the electrophoretic migration of genomic dsRNA.

A nucleation site and mechanism leading to epitaxial growth of diamond films

A diamond nucleation site responsible for epitaxial growth of diamond on silicon by chemical vapor deposition (CVD) is identified in high-resolution transmission electron microscopic images. Other sites in the same sample leading to polycrystalline growth, but deleterious to epitaxial CVD growth, are also described. A mechanism for the heteroepitaxial growth of diamond is suggested, in which etching of the nondiamond carbon binder exposes and removes nonadherent nanodiamond nuclei, leaving intact only those directly nucleated on the silicon substrate. This work enhances our understanding of diamond nucleation and heteroepitaxial growth and its potential applications.

Survey of 160 centenarians in Shanghai

One hundred and sixty centenarians were discovered and followed up for 7 years (1982-88) in Shanghai. The proportion of centenarians in the population was non-significantly greater in the urban than in the rural area and centenarians were in general increasing in both areas over the years. The factors promoting longevity were good medical care and benevolent attention from family members. Autopsy was performed in eight centenarians revealing the main causes of death as pneumonia and cancer.