Correction: Kim et al. Mito-TIPTP Increases Mitochondrial Function by Repressing the Rubicon-p22phox Interaction in Colitis-Induced Mice. Antioxidants 2021, 10, 1954.

In the original publication [...].

Single-string, closed-loop fixation modification to reposit a dislocated triple-looped haptic intraocular lens.

A technique using the single-string, closed-loop fixation method to reposit dislocated triple-looped haptic intraocular lens (IOL)-capsular bag complex is described. The long needle or curved needle with a 10-0/8-0 polypropylene suture and a 27/30-gauge needle were used as the guide needle to pass through the fenestrated haptics twice. The scleral interlaminar course was used as the fixed point. Last, a fixation knot was created in the sclerotomy by the 2 ends of the thread to close the suture loop for IOL fixation. Another knot was created about 2 to 3 mm from the exit point and was intrasclerally anchored by the aid of the attached needle. 4 eyes from 4 consecutive patients were studied retrospectively; during all follow-up visits, the IOLs were well centered and stable, and no suture erosion, hypotony, scleral atrophy, chronic inflammation, retinal tears, and/or detachments were observed.

Point mutation of V252 in neomycin C epimerase enlarges substrate-binding pocket and improves neomycin B accumulation in Streptomyces fradiae.

Neomycin, an aminoglycoside antibiotic with broad-spectrum antibacterial resistance, is widely used in pharmaceutical and agricultural fields. However, separation and purification of neomycin B as an active substance from Streptomyces fradiae are complicated. Although NeoN can catalyze conversion of neomycin C to neomycin B, the underlying catalytic mechanism is still unclear. In this study, the genomic information of high-yielding mutant S. fradiae SF-2 was elucidated using whole-genome sequencing. Subsequently, the mechanism of NeoN in catalyzing conversion of neomycin C to neomycin B was resolved based on NeoN-SAM-neomycin C ternary complex. Mutant NeoNV252A showed improved NeoN activity, and the recombinant strain SF-2-NeoNV252A accumulated 16,766.6 U/mL neomycin B, with a decrease in neomycin C ratio from 16.1% to 6.28%, when compared with the parental strain SF-2. In summary, this study analyzed the catalytic mechanism of NeoN, providing significant reference for rational design of NeoN to improve neomycin B production and weaken the proportion of neomycin C.

Mito-TIPTP Increases Mitochondrial Function by Repressing the Rubicon-p22phox Interaction in Colitis-Induced Mice.

The run/cysteine-rich-domain-containing Beclin1-interacting autophagy protein (Rubicon) is essential for the regulation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase by interacting with p22phox to trigger the production of reactive oxygen species (ROS) in immune cells. In a previous study, we demonstrated that the interaction of Rubicon with p22phox increases cellular ROS levels. The correlation between Rubicon and mitochondrial ROS (mtROS) is poorly understood. Here, we report that Rubicon interacts with p22phox in the outer mitochondrial membrane in macrophages and patients with human ulcerative colitis. Upon lipopolysaccharide (LPS) activation, the binding of Rubicon to p22phox was elevated, and increased not only cellular ROS levels but also mtROS, with an impairment of mitochondrial complex III and mitochondrial biogenesis in macrophages. Furthermore, increased Rubicon decreases mitochondrial metabolic flux in macrophages. Mito-TIPTP, which is a p22phox inhibitor containing a mitochondrial translocation signal, enhances mitochondrial function by inhibiting the association between Rubicon and p22phox in LPS-primed bone-marrow-derived macrophages (BMDMs) treated with adenosine triphosphate (ATP) or dextran sulfate sodium (DSS). Remarkably, Mito-TIPTP exhibited a therapeutic effect by decreasing mtROS in DSS-induced acute or chronic colitis mouse models. Thus, our findings suggest that Mito-TIPTP is a potential therapeutic agent for colitis by inhibiting the interaction between Rubicon and p22phox to recover mitochondrial function.

MiR-224 ameliorates inflammation and symptoms in mouse model of allergic rhinitis by targeting CDK9.

OBJECTIVES: To explore the regulatory effects of microRNA (miRNA)-224 and its potential target gene, cyclin dependent kinase 9 (CDK9), in the pathological process of allergic rhinitis (AR). METHODS: To investigate the role of miR-224 and CDK9, it was screened by bioinformatics prediction software and verified by dual-luciferase reporter assay. The mouse model of AR was established by ovalbumin (OVA).The animal models were intervened with miR-224 agomir, negative control agomir, and saline respectively. The symptoms of sneezing and nasal rubbing were recorded. The expressions of miR224, CDK9, and cytokines in the nasal mucosa of different groups were analyzed by rt-PCR or western blotting. Enzyme-linked immunoassay (ELISA) was used to evaluate the levels of IgE and Histamine (HA) in the serum. The infiltration of inflammatory cells in the nasal mucosa was studied by immunohistochemistry. The expression and distribution of CDK9 in the nasal mucosa of mice were revealed by immunofluorescence. RESULTS: In the nasal mucosa of the animal models, the level of miR-224 was downregulated, while that of CDK9 was upregulated. The upregulation of miR-224 by miR-224 agomir reduced the frequencies of nasal rubbing and sneezing, the expression of CDK9, the levels of cytokines, and the concentrations of IgE and HA. Moreover, miR-224 appeared to attenuate the infiltration of inflammatory cells and hypersecretion of glands in the nasal mucosa. The expression of CDK9, which was distributed under the mucosa, especially in the submucosa interstitial tissue, was significantly reduced. CONCLUSION: MiR-224 affected the pathogenesis of AR by targeting CDK9. It proves that miR-224 could be a novel potential therapeutic target for AR.

Autologous tenon capsule packing to treat posterior exit wound of penetrating injury: A case report.

BACKGROUND: This study reports a case of autologous tenon capsule packing to treat the posterior exit wound of penetrating injury. CASE SUMMARY: To treat a 58-year-old male patient with penetrating eyeball injury caused by an iron sheet, we used autologous tenon capsule packing. Two months after removal of the silicone oil, the corrected visual acuity was 0.3, the retina was flat, the tenon capsule graft was in place, the posterior wound closed well, and the intraocular pressure was 15.8 mmHg. CONCLUSION: Autologous tenon capsule packing to treat the posterior exit wound of penetrating injury is safe and effective.

Scleral Buckling with Viscoelastics or Gas Injection for Bulging Retinal Detachments: A Retrospective Cohort Study.

OBJECTIVE: To examine the use of a viscoelastic agent instead of air in the vitreous cavity during surgery for scleral buckling. METHODS: This was a retrospective cohort study of patients who underwent scleral buckling surgery for bulging rhegmatogenous retinal detachment (RRD) at Ningbo Eye Hospital from 07/2016 to 12/2019. The patients were grouped into drainage, air injection, cryotherapy and explant (DACE) and drainage, viscoelastic injection, cryotherapy, and explant (DVCE) groups, which were comparatively assessed. RESULTS: There were 25 and 22 patients in the DVCE and DACE groups, respectively. The surgery was significantly shorter with DVCE than DACE (P < 0.05), with less intraoperative external pressure adjustment (P < 0.05). BCVA was lower in the DVCE group at 1 week compared with the DACE group (P < 0.05). Successful retinal reattachment was observed in 92.0% and 81.8% of the DVCE and DACE groups, respectively (P < 0.05). Cases requiring laser replenishing after the operation were less in the DVCE group compared with the DACE group (P < 0.05). There were no differences in complications and intraocular pressure between the two groups (all P < 0.05). CONCLUSION: DVCE has better operative characteristics and faster vision recovery than DACE, with similar outcomes.

Salvianolic acid B inhibits myofibroblast differentiation and extracellular matrix accumulation in nasal polyp fibroblasts via the TGF-ß1 signaling pathway.

In the process of nasal tissue remodeling, nasal fibroblasts serve an important role via myofibroblast differentiation and the production of extracellular matrix (ECM). Nasal fibroblast abnormalities can lead to conditions such as chronic rhinosinusitis. Salvianolic acid B (Sal B), a water-soluble active pharmaceutical compound extract from the root of the traditional Chinese medicine Salvia miltiorrhiza, displays antioxidative, antiproliferative and antifibrosis properties. The present study aimed to investigate the mechanism underlying the effects of Sal B on nasal polyp fibroblast (NPF) myofibroblast differentiation and ECM accumulation. Primary NPFs were obtained from nasal polyps of patients with chronic sinusitis. The proliferative and cytotoxic effects of Sal B on NPFs were evaluated by performing the Cell Counting Kit-8 assay. The Transwell assay was conducted to assess cell migration. α-smooth muscle actin (α-SMA), TGF-ß1 receptor (TßR)-I, TßR-II, Smad2/3 mRNA and protein expression levels and (p)-Smad2/3 phosphorylation levels were measured via reverse transcription-quantitative PCR and western blotting, respectively. Type III collagen and fibronectin levels were analyzed by ELISA. The results indicated that Sal B significantly downregulated TGF-ß1-induced α-SMA, fibronectin and collagen III expression levels in NPFs. Similarly, Sal B significantly decreased TGF-ß1-induced TßR-I, TßR-II, p-Smad2/3, MMP-2 and MMP-9 mRNA and protein expression levels in NPFs. Furthermore, Sal B significantly decreased TGF-ß1-induced NPF migration. Therefore, the present study indicated that Sal B inhibited myofibroblast differentiation and ECM accumulation in nasal fibroblasts, suggesting that Sal B may inhibit nasal polyp formation via certain mechanisms.

Factors associated with difficult intravenous access in the pediatric emergency department.

BACKGROUND: Successful intravenous catheter placement plays a vital role in the pediatric emergency department. We assessed pediatric emergency department-related factors associated with difficult intravenous catheter placement. METHOD: We retrospectively reviewed the electronic medical records of patients younger than 18 years who had an intravenous catheter placement attempt during their pediatric emergency department stay. Difficult intravenous access was defined as intravenous catheter placement requiring more than one attempt. The demographic-, clinical- and procedure-related factors were collected, and a logistic regression analysis was used to evaluate the factors associated with difficult intravenous access. RESULT: In total, 925 patients were enrolled, and 77 (8.32%) cases had difficult intravenous access. The median age of the patients was 3.0 (interquartile range = 1-9) years, and 496 (53.6%) patients were male. After adjustment, we found that age (odds ratio = 0.91, 95% confidence interval = (0.85-0.98), p = 0.01); a history of prematurity (odds ratio = 2.31, 95% confidence interval (1.08-4.98), p = 0.03); the intravenous catheter insertion site (foot versus hand odds ratio = 5.65, 95% confidence interval = (2.97-10.75); p < 0.001); and the experience of the provider (<6 months versus ⩾12 months odds ratio = 4.59, 95% confidence interval = (1.92-11.01), p = 0.01) were associated with difficult intravenous access. However, the acuity of disease, crowdedness at the pediatric emergency department, sex, vein visibility, vein palpability, intravenous catheter size, patients' experience with intravenous access, and time of day were not significantly correlated with difficult intravenous access. CONCLUSION: The success rate of intravenous catheter placement at the pediatric emergency department could be improved by experienced providers. The acuity of disease and crowdedness at the pediatric emergency department were not significantly associated factors.

Gene expression profile in mouse bacterial chronic rhinosinusitis.

Persistent infection in the paranasal sinuses impairs sinus drainage and leads to bacterial chronic rhinosinusitis. Greater knowledge of the key molecules in the pathology will help to clarify the pathogenesis. Study of the gene expression profile and analysis of the associated pathway is important to identify key molecules. This study investigates the expression of different genes and analyzes the key pathway in the pathological process of bacterial chronic rhinosinusitis. Bacterial chronic rhinosinusitis was induced in mice using a Merocel nasal pack inoculated with Staphylococcus aureus. Three months of mucosa samples were collected for histological and ELISA analysis, and gene expression was tested using DNA microarray. Differentially expressed genes were selected and verified for pathway analysis. The nasal mucosa of mice with chronic rhinosinusitis showed epithelial damage and lamina propria edema in extra cellular matrix with obvious mucosal inflammation. A total of 6,018 genes in bacterial chronic rhinosinusitis group were differentially expressed compared with the control. Among them, plasma, coagulation factors, urokinase plasminogen activator and urokinase receptor plasminogen activator expression were increased. Following gene ontology analysis and reverse transcription-quantitative polymerase chain reaction, coagulation cascades associated cytokines were found to be upregulated in bacterial chronic rhinosinusitis. The present results suggest that, bacterial chronic rhinosinusitis showed severe mucosal inflammation and genes differential expression in the pathogenesis. In this process, the coagulation cascades pathways were upregulated.

uPA affects the CRSsNP nasal mucosa epithelium apoptosis by regulating WIF1.

Chronic rhinosinusitis without nasal polyps (CRSsNP) is the main type of Chronic rhinosinusitis (CRS) and is a common otorhinolaryngologic disease worldwide. However, the mechanisms of CRSsNP remain poorly understood. In this study, C57BL/6J wild-type and urokinase-type plasminogen activator (uPA) gene knockout (uPA-/-) mice were used to construct the CRSsNP model. Primary human nasal epithelial cells (HNEC) were isolated from CRSsNP patient and treated with uPA knockdown/overexpression lentivirus. CCK-8 and Annexin-V/PI staining were used to detected cell proliferation and apoptosis. In vivo, we found that uPA depletion alleviated mucosal inflammation in the CRSsNP mice model. Wnt inhibitory factor 1 (WIF1) was upregulated in the uPA-/- CRSsNP mice model. In vitro, inhibition of uPA increased cell proliferation and decreased cell apoptosis. Mechanistically, uPA depletion upregulated WIF1 and BCL2 expression, and reduced the expression level of BAX in CRSsNP HNEC. In contrast, decreased cell proliferation and increased cell apoptosis were observed after uPA overexpression. Consistently, a reduction in WIF1 and BCL2 expression levels and an increase in the BAX expression level were observed upon uPA ectopic expression. Furthermore, WIF1 overexpression rescued the effects caused by uPA overexpression in vitro. In conclusion, uPA affects the CRSsNP nasal mucosal epithelium cell apoptosis by upregulating WIF1. To our knowledge, this is the first study to explore the role of uPA in CRSsNP to date.

Roles of dynamical symmetry breaking in driving oblate-prolate transitions of atomic clusters.

This paper explores the driving mechanisms for structural transitions of atomic clusters between oblate and prolate isomers. We employ the hyperspherical coordinates to investigate structural dynamics of a seven-atom cluster at a coarse-grained level in terms of the dynamics of three gyration radii and three principal axes, which characterize overall mass distributions of the cluster. Dynamics of gyration radii is governed by two kinds of forces. One is the potential force originating from the interactions between atoms. The other is the dynamical forces called the internal centrifugal forces, which originate from twisting and shearing motions of the system. The internal centrifugal force arising from twisting motions has an effect of breaking the symmetry between two gyration radii. As a result, in an oblate isomer, activation of the internal centrifugal force that has the effect of breaking the symmetry between the two largest gyration radii is crucial in triggering structural transitions into prolate isomers. In a prolate isomer, on the other hand, activation of the internal centrifugal force that has the effect of breaking the symmetry between the two smallest gyration radii is crucial in triggering structural transitions into oblate isomers. Activation of a twisting motion that switches the movement patterns of three principal axes is also important for the onset of structural transitions between oblate and prolate isomers. Based on these trigger mechanisms, we finally show that selective activations of specific gyration radii and twisting motions, depending on the isomer of the cluster, can effectively induce structural transitions of the cluster. The results presented here could provide further insights into the control of molecular reactions.

Effects of simvastatin on the portal-systemic collateral vascular response to endothelin-1 and shunting degree in portal hypertensive rats.

OBJECTIVE: Endothelin-1 (ET-1) exerts vasoconstrictive effect on portal-systemic collateral vascular bed of portal hypertensive rats. Statins are lipid-lowering agents with nitric oxide (NO)-related vasodilatory effects. Considering NO-associated vascular hyporesponsiveness to vasoconstrictors and shunting formation in portal hypertension, this study investigated the effects of simvastatin on 1) the portal-systemic collateral vascular responsiveness to ET-1 and 2) the portal-systemic shunting degree. MATERIALS/METHODS: Portal hypertension was induced by partial portal vein ligation (PVL) in Sprague-Dawley rats. Simvastatin (20 mg/kg/day) or distilled water (control) was randomly administered by oral gavage since 2 days prior to until 7 days after PVL. Systemic and portal hemodynamics were measured on the 8th day. In another series, collateral perfusion with Krebs solution at different flow rates was performed to get flow-pressure curves which serve as an index of shunting degree. To survey the direct vascular effect, PVL rats randomly underwent preincubation with 1) Krebs solution, that is, the control group; or Krebs solution plus 2) simvastatin; 3) simvastatin + N (ω)-nitro-L-arginine (NNA, a NO synthase inhibitor); 4) simvastatin + indomethacin (a cyclooxygenase inhibitor), followed by ET-1 to evaluate the collateral vascular responsiveness. RESULTS: Chronic simvastatin treatment significantly reduced portal pressure. The flow-pressure curves were similar between two groups. Simvastatin preincubation reduced collateral perfusion pressure changes to ET-1 (p < 0.05), which were partially reversed by NNA (p < 0.05), but not by indomethacin. Conclusions. Chronic simvastatin treatment significantly improved portal hypertension. The effect was at least partially exerted by decreased portal-systemic collateral vascular resistance through NO-mediated vascular hyporesponsiveness. The severity of portal-systemic collaterals was not influenced by simvastatin.

Control of a model of DNA division via parametric resonance.

We study the internal resonance, energy transfer, activation mechanism, and control of a model of DNA division via parametric resonance. While the system is robust to noise, this study shows that it is sensitive to specific fine scale modes and frequencies that could be targeted by low intensity electro-magnetic fields for triggering and controlling the division. The DNA model is a chain of pendula in a Morse potential. While the (possibly parametrically excited) system has a large number of degrees of freedom and a large number of intrinsic time scales, global and slow variables can be identified by (1) first reducing its dynamic to two modes exchanging energy between each other and (2) averaging the dynamic of the reduced system with respect to the phase of the fastest mode. Surprisingly, the global and slow dynamic of the system remains Hamiltonian (despite the parametric excitation) and the study of its associated effective potential shows how parametric excitation can turn the unstable open state into a stable one. Numerical experiments support the accuracy of the time-averaged reduced Hamiltonian in capturing the global and slow dynamic of the full system.

Possible association of NAT2 polymorphism with laryngeal cancer risk: an evidence-based meta-analysis.

PURPOSE: N-acetyltransferase 2 (NAT2) plays an important role in the metabolism of various potential carcinogens, which can be subdivided into rapid and slow acetylation phenotype according to the different genotypes. A number of studies have been devoted to the association of NAT2 polymorphism with susceptibility to laryngeal carcinoma; however, the results were inconsistent and inconclusive. The aim of the present study was to conduct a meta-analysis assessing the possible association of NAT2 polymorphism with laryngeal cancer risk. METHODS: The relevant studies were identified through a search of PubMed, Embase, ISI Web of Knowledge, and Chinese National Knowledge Infrastructure until February 2011 and selected on the basis of the established inclusion criteria for publications, and then a meta-analysis was performed to quantitatively summarize the association of NAT2 polymorphism with laryngeal cancer susceptibility. RESULTS: Seven studies were included in the present meta-analysis, which described a total of 980 laryngeal cancer cases and 1,487 controls. The overall odds ratio (OR) for NAT2 slow and rapid acetylators was 0.99 (95% CI = 0.71-1.38) and 1.01 (95% CI = 0.72-1.40), respectively. When stratifying for race, the pooled ORs for NAT2 slow acetylator were 1.99 (95% CI = 1.10-3.63) in Asians and 0.85 (95% CI = 0.62-1.15) in Caucasians, and the pooled ORs for NAT2 rapid acetylator were 0.50 (95% CI = 0.28-0.91) in Asians and 1.18 (95% CI = 0.87-1.60) in Caucasians. CONCLUSIONS: This meta-analysis suggested that there was overall lack of association between NAT2 polymorphism and laryngeal cancer risk; however, NAT2 slow acetylation may contribute to a risk factor for laryngeal cancer in Asians but not in Caucasians.

Intramolecular energy transfer and the driving mechanisms for large-amplitude collective motions of clusters.

This paper uncovers novel and specific dynamical mechanisms that initiate large-amplitude collective motions in polyatomic molecules. These mechanisms are understood in terms of intramolecular energy transfer between modes and driving forces. Structural transition dynamics of a six-atom cluster between a symmetric and an elongated isomer is highlighted as an illustrative example of what is a general message. First, we introduce a general method of hyperspherical mode analysis to analyze the energy transfer among internal modes of polyatomic molecules. In this method, the (3n-6) internal modes of an n-atom molecule are classified generally into three coarse level gyration-radius modes, three fine level twisting modes, and (3n-12) fine level shearing modes. We show that a large amount of kinetic energy flows into the gyration-radius modes when the cluster undergoes structural transitions by changing its mass distribution. Based on this fact, we construct a reactive mode as a linear combination of the three gyration-radius modes. It is shown that before the reactive mode acquires a large amount of kinetic energy, activation or inactivation of the twisting modes, depending on the geometry of the isomer, plays crucial roles for the onset of a structural transition. Specifically, in a symmetric isomer with a spherical mass distribution, activation of specific twisting modes drives the structural transition into an elongated isomer by inducing a strong internal centrifugal force, which has the effect of elongating the mass distribution of the system. On the other hand, in an elongated isomer, inactivation of specific twisting modes initiates the structural transition into a symmetric isomer with lower potential energy by suppressing the elongation effect of the internal centrifugal force and making the effects of the potential force dominant. This driving mechanism for reactions as well as the present method of hyperspherical mode analysis should be widely applicable to molecular reactions in which a system changes its overall mass distribution in a significant way.

[Research of the expression of PTEN in squamous cell carcinoma of larynx by the tissue chip technology].

OBJECTIVE: To evaluate the expression of PTEN in squamous cell carcinoma of larynx and its relationship with factors like pathologic fractionation, clinical TNM stage, and prognosis by the tissue chip technology. METHOD: We studied the expression of PTEN gene and its mRNA on a series of 146 cases of primary laryngeal carcinoma patients, 40 cases of precancerous lesion and 26 cases of vocal fold polyp by tissue chip by, immunohistochemistry and in situ hybridization method. The observed data observed and some relevant clinical dada were statistically analyzed. RESULT: The expression of PTEN in vocal fold polyp was negative, and its positive expression in precancerous lesion and laryngeal carcinoma were 40% and 43.15% respectively by immunohistochemistry, and were 72.50 and 59.59% respectively in situ hybridization. The difference between the expression of PTEN in laryngeal carcinoma and its pathological fraction and prognosis was statistically significant, but was not significant between that and location, clinical stage and LN metastasis. The mRNA expression of PTEN was higher than that of the protein expression in precancerous lesion and cancer tissue. CONCLUSION: The tissue microarray technique required shorter time and less expense, and showed higher consistency in our essays. And the present study suggests PTEN was a prognosis factor of the Laryngeal carcinoma.

[Expression of S-100 positive dendritic cell, TIMP-1 and p63 and its significance in the primary laryngeal carcinoma].

OBJECTIVE: To evaluate the predictive role of S-100 positive dendritic cell, tissue inhibitor of metalloproteinases-1 (TIMP-1) and p63 gene in primary laryngeal carcinoma with epidemiology (smoking and drinking), histological grading, surgical treatment, TNM stage and prognosis by the tissuechip technology. METHODS: We studied the expression of dendritic cell (S-100), TIMP-1 and p63 gene on a series of 85 primary laryngeal carcinoma patients who had ever received in our hospital between 1992 and 2000 by the tissuechip technology and SP method. The correlation of each score according to the intensity and percentage of labeled cells or intercellular substance with relevant clinical dada was statistically analyzed. RESULT: Some cases were lost or boasted no tumor tissue in our tissuechip. In available 79 patients, the rate of expressing S-100 positive dendritic cell is 59.5% (47/79), and the average percentage of its labeled cells in them is 8.71%. S-100 positive dentritic cells showed significant difference among different pathological grade group, early and late stage( P < 0.05). The rate is 55.7% (44/79) of the specimens whose basal membrane and extracellular matrix was strongly stained by TIMP-1; There was statistical significant in TIMP-1 protein demonstration between early and late stages, lymph node metastasis and 3-year survival rate ( P < 0.05) by chi-square test, but no relation with smoking, drinking, gender, age and histological classes (P > 0.05). There was wo statistical significant in p63 protein demonstration between TNM stages, lymph node metastasis, 3-year survival rate, smoking, drinking, gender, age and histological classes (P > 0.05). CONCLUSION: The tissue microarray technique spent shorter time and less expense, and showed higher consistency in our essays. And the present study suggests TIMP-1 and S-100 could be the clinical discriminators in laryngeal carcinoma.

Geometric mechanics and the dynamics of asteroid pairs.

The purpose of this paper is to describe the general setting for the application of techniques from geometric mechanics and dynamical systems to the problem of asteroid pairs. The paper also gives some preliminary results on transport calculations and the associated problem of calculating binary asteroid escape rates. The dynamics of an asteroid pair, consisting of two irregularly shaped asteroids interacting through their gravitational potential is an example of a full-body problem or FBP in which two or more extended bodies interact. One of the interesting features of the binary asteroid problem is that there is coupling between their translational and rotational degrees of freedom. General FBPs have a wide range of other interesting aspects as well, including the 6-DOF guidance, control, and dynamics of vehicles, the dynamics of interacting or ionizing molecules, the evolution of small body, planetary, or stellar systems, and almost any other problem in which distributed bodies interact with each other or with an external field. This paper focuses on the specific case of asteroid pairs using techniques that are generally applicable to many other FBPs. This particular full two-body problem (F2BP) concerns the dynamical evolution of two rigid bodies mutually interacting via a gravitational field. Motivation comes from planetary science, where these interactions play a key role in the evolution of asteroid rotation states and binary asteroid systems. The techniques that are applied to this problem fall into two main categories. The first is the use of geometric mechanics to obtain a description of the reduced phase space, which opens the door to a number of powerful techniques, such as the energy-momentum method for determining the stability of equilibria and the use of variational integrators for greater accuracy in simulation. Second, techniques from computational dynamic systems are used to determine phase space structures that are important for transport phenomena and dynamic evolution.

Application of tissue microarray: evaluation of the expression of S-100-positive dendritic cells, tumor suppressor gene p63 and tissue inhibitor of metalloproteinase-1 in laryngeal carcinoma.

OBJECTIVE: To evaluate the predictive role of S100-positive dendritic cells, tissue inhibitor of metalloproteinase-1 (TIMP1) and p63 gene in laryngeal carcinoma using a tissue chip. MATERIAL AND METHODS: The expression of dendritic cells, TIMP1 and p63 gene in a series of 85 primary laryngeal carcinoma patients who had undergone operations in our hospital between 1992 and 2000 was studied immunohistochemically using the streptavidin-biotin peroxidase-conjugated method. RESULTS: Some cases were lost or showed no tumor tissue in the tissue chip. The rate of expression of dendritic cells was 59.5% and there were significant differences in expression between the differential degrees of laryngeal squamous carcinoma and the different clinical stages (p <0.05). The basal membrane and extracellular matrix of the specimens were strongly stained by TIMP1 in 55.7% of cases. There were statistically significant correlations between TIMP1 protein expression and early- and advanced-stage tumors, lymph node metastasis and 3-year survival rate (p <0.05). No statistically significant correlations were found between p63 protein expression and any of the clinical parameters. CONCLUSIONS: The tissue microarray technique used in this study is quick, inexpensive and very consistent. It is suggested that TIMP1 and S100 should be used as clinical discriminators of laryngeal carcinoma.