Clinical features and outcomes of advanced HER2+ esophageal/GEJ cancer with brain metastasis

BACKGROUND

Brain metastasis (BRM) is uncommon in gastroesophageal cancer. As such, clinicopathologic and molecular determinants of BRM and impact on clinical outcome remain incompletely understood.

METHODS

We retrospectively analyzed clinicopathologic data from advanced esophageal/gastroesophageal junction (E/GEJ) patients at Johns Hopkins from 2003 to 2021. We investigated the association between several clinical and molecular features and the occurrence of BRM, with particular focus on human epidermal growth factor receptor 2 (HER2) overexpression. Survival outcomes and time to BRM onset were also evaluated.

RESULTS

We included 515 patients with advanced E/GEJ cancer. Tumors were 78.3% esophageal primary, 82.9% adenocarcinoma, 31.0% HER2 positive. Cumulative incidence of BRM in the overall cohort and within HER2+ subgroup was 13.8% and 24.3%, respectively. HER2 overexpression was associated with increased risk of BRM [odds ratio 2.45; 95% confidence interval (CI) 1.10-5.46]. On initial presentation with BRM, 50.7% had a solitary brain lesion and 11.3% were asymptomatic. HER2+ status was associated with longer median time to onset of BRM (14.0 versus 6.3 months, P < 0.01), improved median progression free survival on first-line systemic therapy (hazard ratio 0.35, 95% CI 0.16-0.80), and improved median overall survival (hazard ratio 0.20, 95% CI 0.08-0.54) in patients with BRM.

CONCLUSION

HER2 overexpression identifies a gastroesophageal cancer molecular subtype that is significantly associated with increased risk of BRM, though with later onset of BRM and improved survival likely reflecting the impact of central nervous system-penetrant HER2-directed therapy. The prevalence of asymptomatic and solitary brain lesions suggests that brain surveillance for HER2+ patients warrants prospective investigation.

Study on CNT/TPU cube under the 3D printing conditions of infill patterns and density

In this study, to develop soft pressure sensor applicable to wearable robots using stretchable polymers and conductive fillers, 3.25 wt% carbon nanotubes/thermoplastic polyurethane filament with shore 94 A were manufactured. Three infill densities (20%, 50%, and 80%) and patterns (zigzag (ZG), triangle (TR), honeycomb (HN)) were applied to print cubes via fused filament fabrication 3D printing. Most suitable infill conditions were confirmed based on the slicing images, morphologies, compressive properties, electrical properties, and electrical heating properties. For each infill pattern, ZG and TR divided the layers into lines and figures, and the layers were stacked by rotation. For HN, the same layers were stacked in a hexagonal pattern. Consequently, TR divided layer in various directions, showed the strongest compressive properties with toughness 1.99 J for of infill density 80%. Especially, the HN became tougher with increased infill density. Also, the HN laminated with the same layer showed excellent electrical properties, with results greater than 14.7 mA. The electrical heating properties confirmed that ZG and HN had the high layer density, which exhibited excellent heating characteristics. Therefore, it was confirmed that performance varies depending on the 3D printing direction, and it was confirmed that HN is suitable for manufacturing soft sensors.

In Situ Synthesis of Environmentally Friendly Waterborne Polyurethane Extended with Regenerated Cellulose Nanoparticles for Enhanced Mechanical Performances

The development of waterborne polyurethane (WPU) has been stimulated as an alternative to solvent-based polyurethanes due to low-VOC alternatives and reduced exposure to solvents. However, their relatively low mechanical performance and degradation have presented challenges in their wide application. Here, we developed environmentally-friendly bio polyol-based WPU nanocomposite dispersions and films, and presented the optimal process conditions for their manufacture. Additionally, the condition was established without using harmful catalysts or ethyl methyl ketone (MEK) during the polymerization. Moreover, regenerated cellulose nanoparticles (RCNs) were employed as natural chain-extenders in order to improve the biodegradability and mechanical performances of the nanocomposite films. The RCNs have a lower crystallinity compared to cellulose nanocrystals (CNCs), allowing them to possess high toughness without interfering with the elastomeric properties of polyurethane. The prepared CWPU/RCNs nanocomposite films exhibited high toughness of 58.8 ± 3 kgf∙mm and elongation at break of 240 ± 20%. In addition, depending on the molar ratio of NCO/OH, the polyurethane particle size is variously controlled from 70 to 230 nm, enabling to fabricate their dispersions with various transmittances. We believe that our findings not only open a meaningful path toward green elastomers with biodegradability but provides the design concept for bio-elastomers in order to develop industrial elastomers with mechanical and thermal properties.

Synthesis and properties of bio-based thermoplastic poly(ether urethane) for soft actuators

In this study, bio-based thermoplastic polyurethane (TPU) for use in soft actuators is bio-based poly(ether-urethane) made using fermented corn, along with bio-derived compounds such as propane-1,3-diol (PDO) as a chain extender. Bio-based TPUs were obtained through a solvent-free one-shot synthesis method, and the effects of varying the [NCO]/[OH] molar ratio and type of isocyanates on chemical structure, thermal stability, and mechanical properties were investigated. The degree of phase separation (DPS) and state of hard segment (HS) / soft segment (SS) of TPU are important factors affecting the thermal and physical properties of the prepared film. These properties depend on the [NCO]/[OH] molar ratio and the type of isocyanates used for polymerization. The results showed that, when aromatic isocyanate was used, the degree of separation of the HS/SS was improved as the molar ratio increased. The average molecular weight and DPS as well as thermal and mechanical properties of 1-isocyanato-4-[(4-isocyanatophenyl)methyl]benzene (MDI)-based TPU samples are all higher than those of 1,1’-methylenebis(4-isocyanatocyclohexane) (H12MDI)-based TPU samples in spite of the lower HS content. These findings of this study are expected to contribute to the preparation of fused deposition modeling (FDM) 3D printing or 4D printing for shape memory polymer from bio-based TPU filaments for use in soft actuators with a shore hardness range of 59~84A.

Design and evaluation of 3D-printed auxetic structures coated by CWPU/graphene as strain sensor

A strain sensor characterized by elasticity has recently been studied in various ways to be applied to monitoring humans or robots. Here, 4 types of 3D-printed auxetic lattice structures using thermoplastic polyurethane as raw material were characterized: truss and honeycomb with positive Poisson's ratio and chiral truss and re-entrant with negative Poisson's ratio. Each structure was fabricated as a flexible and stable strain sensor by coating graphene through a dip-coating process. The fabricated auxetic structures have excellent strength, flexibility, and electrical conductivity desirable for a strain sensor and detect a constant change in resistance at a given strain. The 3D-printed auxetic lattice 4 type structures coated with CWPU/Graphene suggest potential applications of multifunctional strain sensors under deformation.

Bacterial Cellulose and Its Applications

The sharp increase in the use of cellulose seems to be in increasing demand in wood; much more research related to sustainable or alternative materials is necessary as a lot of the arable land and natural resources use is unsustainable. In accordance, attention has focused on bacterial cellulose as a new functional material. It possesses a three-dimensional, gelatinous structure consisting of cellulose with mechanical and thermal properties. Moreover, while a plant-originated cellulose is composed of cellulose, hemi-cellulose, and lignin, bacterial cellulose attributable to the composition of a pure cellulose nanofiber mesh spun is not necessary in the elimination of other components. Moreover, due to its hydrophilic nature caused by binding water, consequently being a hydrogel as well as biocompatibility, it has only not only used in medical fields including artificial skin, cartilage, vessel, and wound dressing, but also in delivery; some products have even been commercialized. In addition, it is widely used in various technologies including food, paper, textile, electronic and electrical applications, and is being considered as a highly versatile green material with tremendous potential. However, many efforts have been conducted for the evolution of novel and sophisticated materials with environmental affinity, which accompany the empowerment and enhancement of specific properties. In this review article, we summarized only industry and research status regarding BC and contemplated its potential in the use of BC.

Enhanced osseointegration through direct energy deposition porous coating for cementless orthopedic implant fixation

Direct energy deposition (DED) is a newly developed 3D metal printing technique that can be utilized on a porous surface coating of joint implants, however there is still a lack of studies on what advantages DED has over conventional techniques. We conducted a systematic mechanical and biological comparative study of porous coatings prepared using the DED method and other commercially available technologies including titanium plasma spray (TPS), and powder bed fusion (PBF). DED showed higher porosity surface (48.54%) than TPS (21.4%) and PBF (35.91%) with comparable fatigue cycle. At initial cell adhesion, cells on DED and PBF surface appeared to spread well with distinct actin stress fibers through immunofluorescence study. It means that the osteoblasts bind more strongly to the DED and PBF surface. Also, DED surface showed higher cell proliferation (1.27 times higher than TPS and PBF) and osteoblast cell activity (1.28 times higher than PBF) for 2 weeks culture in vitro test. In addition, DED surface showed better bone to implant contact and new bone formation than TPS in in vivo study. DED surface also showed consistently good osseointegration performance throughout the early and late period of osseointegration. Collectively, these results show that the DED coating method is an innovative technology that can be utilized to make cementless joint implants.

Establishment and characterization of patient-derived xenografts as paraclinical models for head and neck cancer

Background

We investigated whether head and neck squamous cell carcinoma (HNSCC) patient-derived xenografts (PDXs) reaffirm patient responses to anti-cancer therapeutics.

Methods

Tumors from HNSCC patients were transplanted into immunodeficient mice and propagated via subsequent implantation. We evaluated established PDXs by histology, genomic profiling, and in vivo anti-cancer efficacy testing to confirm them as the authentic in vivo platform.

Results

From 62 HNSCCs, 15 (24%) PDXs were established. The primary cancer types were tongue (8), oropharynx (3), hypopharynx (1), ethmoid sinus cancer (1), supraglottic cancer (1), and parotid gland (1); six PDXs (40%) were established from biopsy specimens from advanced HNSCC. PDXs mostly retained donor characteristics and remained stable across passages. PIK3CA (H1047R), HRAS (G12D), and TP53 mutations (H193R, I195T, R248W, R273H, E298X) and EGFR, CCND1, MYC, and PIK3CA amplifications were identified. Using the acquisition method, biopsy showed a significantly higher engraftment rate when compared with that of surgical resection (100% [6/6] vs. 16.1% [9/56], P < 0.001). Specimens obtained from metastatic sites showed a significantly higher engraftment rate than did those from primary sites (100% [9/9] vs. 11.3% [6/53], P < 0.001). Three PDX models from HPV-positive tumors were established, as compared to 12 from HPV-negative (15.8% [3/19] and 27.9% [12/43] respectively, P = 0.311), suggesting that HPV positivity tends to show a low engraftment rate. Drug responses in PDX recapitulated the clinical responses of the matching patients with pan-HER inhibitors and pan-PI3K inhibitor.

Conclusions

Genetically and clinically annotated HNSCC PDXs could be useful preclinical tools for evaluating biomarkers, therapeutic targets, and new drug discovery.

Targeting YAP to overcome acquired resistance to ALK inhibitors in ALK-rearranged lung cancer

Clinical benefit of ALK tyrosine kinase inhibitors (ALK‐TKIs) in ALK‐rearranged lung cancer has been limited by the inevitable development of acquired resistance, and bypass‐molecular resistance mechanisms remain poorly understood. We investigated a novel therapeutic target through screening FDA‐approved drugs in ALK‐TKI‐resistant models. Cerivastatin, the rate‐limiting enzyme inhibitor of the mevalonate pathway, showed anti‐cancer activity against ALK‐TKI resistance in vitro/in vivo, accompanied by cytoplasmic retention and subsequent inactivation of transcriptional co‐regulator YAP. The marked induction of YAP‐targeted oncogenes (EGFR, AXL, CYR61, and TGFβR2) in resistant cells was abolished by cerivastatin. YAP silencing suppressed tumor growth in resistant cells, patient‐derived xenografts, and EML4‐ALK transgenic mice, whereas YAP overexpression decreased the responsiveness of parental cells to ALK inhibitor. In matched patient samples before/after ALK inhibitor treatment, nuclear accumulation of YAP was mainly detected in post‐treatment samples. High expression of YAP in pretreatment samples was correlated with poor response to ALK‐TKIs. Our findings highlight a crucial role of YAP in ALK‐TKI resistance and provide a rationale for targeting YAP as a potential treatment option for ALK‐rearranged patients with acquired resistance to ALK inhibitors.

Establishment of a platform of non-small-cell lung cancer patient-derived xenografts with clinical and genomic annotation

BACKGROUND

Preclinical models that can better predict therapeutic activity in clinical trials are needed in this era of personalized cancer treatment. Herein, we established genomically and clinically annotated patient-derived xenografts (PDXs) from non-small-cell lung cancer (NSCLC) patients and investigated whether these PDXs would faithfully recapitulate patient responses to targeted therapy.

METHODS

Patient-derived tumors were implanted in immunodeficient mice and subsequently expanded via re-implantation. Established PDXs were examined by light microscopy, genomic profiling, and in vivo drug testing, and the successful engraft rate was analyzed with the mutation profile, histology, or acquisition method. Finally, the drug responses of PDXs were compared with the clinical responses of the respective patients.

RESULTS

Using samples from 122 patients, we established 41 NSCLC PDXs [30 adenocarcinoma (AD), 11 squamous cell carcinoma (SQ)], among which the following driver mutation were observed: 13 EGFR-mutant, 4 ALK-rearrangement, 1 ROS1-rearrangement, 1 PIK3CA-mutant, 1 FGFR1-amplification, and 2 KRAS-mutant. We rigorously characterized the relationship of clinical features to engraftment rate and latency rates. The engraft rates were comparable across histologic type. The AD engraft rate tended to be higher for surgically resected tissues relative to biopsies, whereas similar engraft rates was observed for SQ, irrespective of the acquisition method. Notably, EGFR-mutants demonstrated significantly longer latency time than EGFR-WT (86 vs. 37days, P = 0.007). The clinical responses were recapitulated by PDXs harboring driver gene alteration (EGFR, ALK, ROS1, or FGFR1) which regressed to their target inhibitors, suggesting that established PDXs comprise a clinically relevant platform.

CONCLUSION

The establishment of genetically and clinically annotated NSCLC PDXs can yield a robust preclinical tool for biomarker, therapeutic target, and drug discovery.

Advances in Waterborne Polyurethane-Based Biomaterials for Biomedical Applications

Polyurethane (PU) is one of the most popular synthetic elastomers and widely employed in biomedical fields owing to the excellent biocompatibility and hemocompatibility known today. In addition, PU is simply prepared and its mechanical properties such as durability, elasticity, elastomer-like character, fatigue resistance, compliance or tolerance in the body during the healing, can be mediated by modifying the chemical structure. Furthermore, modification of bulk and surface by incorporating biomolecules such as anticoagulant s or biorecognizable groups, or hydrophilic/hydrophobic balance is possible through altering chemical groups for PU structure. Such modifications have been designed to improve the acceptance of implant. For these reason, conventional solventborne (solvent-based) PUs have established the standard for high performance systems, and extensively used in medical devices such as dressings, tubing, antibacterial membrane , catheters to total artificial heart and blood contacting materials, etc. However, waterborne polyurethane (WPU) has been developed to improve the process of dissolving PU materials using toxic organic solvents, in which water is used as a dispersing solvent. The prepared WPU materials have many advantages, briefly (1) zero or very low levels of organic solvents, namely environmental-friendly (2) non-toxic, due to absence of isocyanate residues, and (3) good applicability caused by extensive structure/property diversity as well as an environment-friendly fabrication method resulting in increasing applicability. Therefore, WPUs are being in the spotlight as biomaterials used for biomedical applications . The purpose of this review is to introduce an environmental- friendly synthesis of WPU and consider the manufacturing process and application of WPU and/or WPU based nanocomposites as the viewpoint of biomaterials.

Autologous adipose tissue-derived stem cells for the treatment of complex perianal fistulas not associated with Crohn's disease: a phase II clinical trial for safety and efficacy

PURPOSE

Injection of adipose tissue-derived stem cells (ASCs) is a novel method for the treatment of complex perianal fistulas. We aimed to evaluate the safety and efficacy of ASCs in the treatment of complex anal fistulas not associated with Crohn's disease.

METHODS

A phase II clinical trial was performed comparing two different doses of ASCs (group 1: 1 × 10⁷ cells/mL and group 2: 2 × 10⁷ cells/mL). Eligible patients were administered an amount of ASCs proportional to the length of the fistula by injection into the submucosal layer surrounding the internal opening and inside of the fistula tract. ASCs at twice the initial concentration were administered if complete closure was not achieved within 8 weeks. The efficacy endpoint was the complete closure of fistulas 8 weeks after injection. Patients demonstrating complete closure at week 8 were subjected to follow-up for 6 months.

RESULTS

Fifteen patients were injected with ASCs; thirteen completed the study. Complete closure was observed in 69.2% (9/13) of patients at 8 weeks. Three of five patients in group 1, and six of eight in group 2 displayed complete closure; no significant differences were observed between the groups. Six of nine patients who showed complete closure participated in additional follow-up; five (83.3%) showed persistent response at 6 months. No grade 3 or 4 adverse events (AEs) were observed; observed AEs were not related to ASC treatment.

CONCLUSION

ASCs might be a good option for the treatment of complex perianal fistulas are not healed by conventional operative procedures.

Study on the Preparation and Characteristics of Cellulose/Silver Iodide Nanocomposite Film

In this study, the structure and properties of an organic-inorganic composite material prepared from cellulose doped with fine particles of silver iodide (AgI) were examined. The preparation of the composite involved the complexation of cellulose with polyiodide ions, such as I- and 13-, by immersion in iodine/potassium iodide (I2/KI: 0.2, 0.4, 0.6, 0.8, 1.0 M) or potassium iodide (KI: 0.6, 1.2, 1.8, 2.4, 3.0 M) aqueous solutions followed by reaction in a silver nitrate (AgNO3:1.0 M) aqueous solution. These procedures resulted in the in situ formation of fine β-AgI particles within the cellulose matrix. The characteristics and conductivities of prepared cellulose/silver iodide (AgI) nanocomposite films with different I2/KI and KI concentrations were investigated. AgI particle formation and aggregation increased on increasing I2/KI and KI concentrations as determined by SEM. X-ray results showed that KI could penetrate the cellulose crystal region and form AgI particles. The electrical conductivities of nanocomposite films treated with KI were higher than that of I2/KI at < 1.0 M of I2/KI and 3 M of KI, although the weight gain by AgI formation was lower than that of I2/KI. This was also attributed to the formation of smaller AgI particles and crystal defects. Highest electrical conductivity (3.8 x 10(-7) Ω(-1) cm(-1)) was obtained from the cellulose films (1.25 x 10(-11) Ω(-1) cm(-1)) treated with the aqueous solutions of 1.0 M I2/KI and 1.0 M AgNO3.

Polysaccharides as nanocarriers for therapeutic applications

Nanocarriers have shown tremendous potential for the target-specific delivery of proteins, genes and drugs. Nanoparticles are fabricated using different natural and synthetic polymers. Natural polysaccharides are often used as building block for developing nano-sized drug delivery vehicles. The physicochemical properties of these materials, such as excellent biocompatibility, low cytotoxicity, surface charges that interact with DNA, protein and RNA, and cost effectiveness, make them exceptional base materials for nanocarrier fabrication. The mechanism for the complex formation of polysaccharides-DNA includes the electrostatic interactions between cationic polymers and anionic DNA to form polyplexes that offer unique possibilities for overcoming cellular barriers by escaping endosomal trafficking followed by cellular internalization and, consequently, enhancing the efficacy of drug and macromolecule delivery to targeted cells and tissue. Depending upon the cellular uptake and trafficking, nanocarriers are designed for different pharmacological and therapeutic applications. However, specific targeting that improves delivery remains an unsolved challenged. The process by which nanocarriers enter cells has important consequences not only for fate of these particles but also for biological systems and therapeutic applications.

Interlinking of hypoxia and estrogen in thyroid cancer progression

Estrogen aids in neo-vascularization of various tumors during hypoxic conditions, however the role of estrogen within the hypoxic environment of thyroid cancer is not known. In a series of experimentations, using human thyroid cancer cells, we observed that estrogen and hypoxia modulate the hypoxia inducible factor-1 (HIF-1) signaling which is abrogated by the anti-estrogen fulvestrant and the HIF-1 inhibitor YC-1 (3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole). Furthermore, we found that the conditioned medium from estrogen treated thyroid cancer cells lead to enhanced migration and tubulogenesis of human umbilical vein endothelial cells (HUVECs) which is abrogated by HIF-1 inhibitor. These findings, in addition to our previous and other scientific literature data, lead us to conclude that estrogen and hypoxia are interlinked in thyroid cancer and can equally modulate epithelial-endothelial cell interactions by mediating key cellular, metabolic and molecular processes of thyroid cancer progression. We believe that the hormonal component and cellular adaptation to oxygen tension of cancer cells are functionally equivalent with a cellular transition that can be exploited clinically for a combinational approach for thyroid cancer treatment involving antiestrogens as well as anti-hypoxic agents.

Effect of Mn and P on the macroscopic texture of Ti-Nb stabilized interstitial free steels

The effect of Mn and P on the macroscopic texture of Ti-Nb stabilized IF steels was investigated. In order to examine the evolution of microstructure and macroscopic texture during the hot-rolling, cold-rolling and annealing processes, microstructure characterization was conducted for hot-rolled, cold-rolled and annealed specimens. The initial grain size of hot-rolled specimens was a main parameter in determining the development of the macroscopic texture of the annealed specimens.

P5-08-06: Comparison of Mammographic Density between Ductal Carcinoma In Situ and Benign Breast Disease

Background: High breast density is an independent risk factor for breast cancer as well as benign breast diseases. However there are few studies about breast density of ductal carcinoma in situ (DCIS) and benign breast disease(BBD). In this study, we investigated patterns of breast density of DCIS and BBD, and comparatively analyzed breast densities of DCIS and BBD.

Material and Methods From 2008 to 2009, 345 patients underwent surgery for DCIS at Asan Medical Center, and 295 patients for BBD at 2010. We retrospectively reviewed each groups and estimated cranio-caudal view of digital mammogram of unaffected breast by computer-assisted thresholding methods, using Cumulus 4, version 4.0. For BBD we included atypical ductal hyperplasia, fibroadenoma, papilloma(atypical/intraductal), phyllodes tumor(benign/borderline), and excluded unavailable mammogram(mostly, because of scanned films from outside hospitals and previously diagnosed breast cancer).

Results Mean ages of each group were 46.51 year old in DCIS group and 41.43 year old in BBD group, and the mean percentage density(PD) were 44.89% and 45.27%, respectively.

Long-term randomized controlled trial of a novel nanopowder hemostatic agent (TC-325) for control of severe arterial upper gastrointestinal bleeding in a porcine model

BACKGROUND AND STUDY AIM

Endoscopic therapy of brisk upper gastrointestinal bleeding remains challenging. A proprietary nanopowder (TC-325) has been proven to be effective in high pressure bleeding from external wounds. The efficacy and safety of TC-325 were assessed in a survival gastrointestinal bleeding animal model.

METHOD

10 animals were randomized to treatment or sham. All animals received intravenous antibiotics, H2-blockers and heparin (activated clotting time 2 × normal). In a sterile laparotomy the gastroepiploic vessels were dissected, inserted through a 1-cm gastrotomy, and freely exposed in the gastric lumen, and the exposed vessel lacerated by needle knife. The treatment group received TC-325 by a modified delivery catheter while the sham group received no endoscopic treatment. Time to hemostasis, and mortality at 60 minutes, 24 hours, 48 hours, and 7 days were noted. Necropsy was performed in all animals.

RESULTS

Spurting arterial bleeding was achieved in all animals. No control animal showed hemostasis within the first hour compared with 100 % (5 / 5) in the treatment arm (mean 13.8 minutes, P < 0.0079). Durable hemostasis was achieved with no evidence of rebleeding after 1 and 24 hours in 80 % (4 / 5) of the treated animals compared with none in the control group ( P < 0.0098). None of the control animals survived more than 6 hours. Necropsy at 1 week in treated animals revealed healed gastrotomy without foreign body granuloma or embolization to the lung or brain.

CONCLUSION

TC-325 is safe and highly effective in achieving hemostasis in an anticoagulated severe arterial gastrointestinal bleeding animal model.

Non-destructive evaluation of nano-sized structure of thin film devices by using small angle neutron scattering

Nano-sized multi-layers copper-doped SrZrO3, platinum (Pt) and silicon oxide (SiO2) on silicon substrates were prepared by dense plasma focus (DPF) device with the high purity copper anode tip and analyzed by using small angle neutron scattering (SANS) to establish a reliable method for the non-destructive evaluation of the under-layer structure. Thin film was well formed at the time-to-dip of 5 microsec with stable plasma of DPF. Several smooth intensity peaks were periodically observed when neutron beam penetrates the thin film with multi-layers perpendicularly. The platinum layer is dominant to intensity peaks, where the copper-doped SrZnO3 layer next to the platinum layer causes peak broadening. The silicon oxide layer has less effect on the SANS spectra due to its relative thick thickness. The SANS spectra shows thicknesses of platinum and copper-doped SrZnO3 layers as 53 and 25 nm, respectively, which are well agreement with microstructure observation.

Antibacterial effects of vulgarone B from Artemisia iwayomogi alone and in combination with oxacillin

The antibacterial activities of vulgarone B, a component of Artemisia iwayomogi essential oil, were evaluated against some antibiotic-susceptible and -resistant human pathogens. Moreover, the effects of combining antibiotics, such as oxacillin, with vulgarone B were determined in this study. Significant inhibitory activities of Artemisia oils against antibiotic-susceptible and -resistant bacteria were confirmed by broth microdilution methods. The effects of vulgarone B on bacterial morphology and DNA were observed by scanning electron microscope and electrophoresis, respectively. In checkerboard microtiter tests, vulgarone B and A. iwayomogi oil combined with oxacillin resulted in synergism, or additive effects. Moreover, the safety of Artemisia oil and vulgarone B were confirmed in vivo. Both vulgarone B and the essential oil fraction of A. iwayomogi showed significant inhibitory activities against strains of antibioticsusceptible and -resistant bacteria. The oils showed synergism or additive effects when combined with oxacillin against two strains of Staphylococcus aureus. The antibiotic mechanism involved might be related to DNA cleavage. Thus, vulgarone B and the essential oil fraction of A. iwayomogi may be promising candidates for a safe, effective, natural agent active against antibiotic-resistant S. aureus, especially when combined with oxacillin.

Study of the effect of nano-sized precipitates on the mechanical properties of boron-added low-carbon steels by neutron scattering techniques

The effect of nano-sized precipitates on the mechanical properties of boron-added low-carbon steels was studied by neutron scattering techniques such as powder diffraction, small-angle scattering and particle tracking autography.

Small-angle neutron scattering (SANS) and neutron powder diffraction (ND) techniques were used to study quantitatively the effect of nano-sized precipitates and boron addition on the mechanical properties of low-carbon steels. SANS was used to evaluate nano-sized precipitates, smaller than about 600 Å in diameter, and ND was used to determine the weight fraction of the cementite precipitates. Fine core–shell structured spherical precipitates with an average radius of ~50 Å, such as MnS and/or CuS, surrounded by BN layers were observed in the boron-added (BA) low-carbon steels; fine spherical precipitates with an average radius of ~48 Å were mainly observed in the boron-free (BF) low-carbon steels. In the BA steels, the number of boron precipitates, such as BN, Fe₃(C,B) and MnS, surrounded by BN layers increased drastically at higher hot-rolling temperatures. The volume fraction of the fine precipitates of the BA steels was higher than that of the BF steels; this difference is related to the rapid growth of the BN layers on the MnS and CuS precipitates. Boron addition to low-carbon steels resulted in a reduction in strength and an improvement in elongation; this behaviour is related to the reduction of the solute carbon and the nitrogen contents in the ferrite matrix caused by the precipitation of BN, as well by the increase in the volume fraction of the cementites.

Endoscopic retrograde cholangiopancreatography, but not esophagogastroduodenoscopy or colonoscopy, significantly increases portal venous pressure: direct portal pressure measurements through endoscopic ultrasound-guided cannulation

BACKGROUND AND STUDY AIMS

Changes in portal pressure during endoscopy have not been previously evaluated. The aims of this study were to assess the effect of esophagogastroduodenoscopy (EGD), colonoscopy, and endoscopic retrograde cholangiopancreatography (ERCP) on portal vein, inferior vena cava (IVC), and systemic pressures.

PATIENTS AND METHODS

Five acute experiments were performed on 50-kg pigs utilizing endoscopic ultrasound (EUS)-guided catheterization of the portal vein and IVC. Systemic, intra-abdominal, IVC, and portal vein pressures were monitored during colonoscopy, EGD, and ERCP with endoscopic sphincterotomy. After endoscopy the animals were sacrificed for necropsy. The main outcome measure was pressure change during each type of endoscopic procedure.

RESULTS

There were no significant changes in heart rate or systemic pressure during all endoscopic procedures. Intra-abdominal pressure increased during colonoscopy ( P = 0.02) and ERCP ( P = 0.007). However, mean portal venous pressure was significantly elevated only after the injection of contrast into the common bile duct, reaching its peak value at the time of biliary sphincterotomy (39.0 +/- 15.2 mm Hg vs. 13.4 +/- 3.6 mm Hg at baseline, P = 0.006). Mean peak IVC pressure was also elevated during ERCP, but it did not reach statistical significance (24.0 +/- 10.7 mm Hg vs. 12.6 +/- 4.1 mm Hg at baseline, P = 0.06).

CONCLUSION

EGD and colonoscopy did not cause significant changes in portal vein, IVC, or systemic pressures. ERCP with biliary sphincterotomy increased portal pressure with only limited effect on IVC and systemic pressures. These new data indicate a possible connection between ERCP with sphincterotomy and portal pressure, and may be clinically important for patients with liver disease and other causes of portal hypertension who undergo this procedure.

Severity of post-ERCP pancreatitis directly proportional to the invasiveness of endoscopic intervention: a pilot study in a canine model

BACKGROUND AND STUDY AIMS

Pancreatitis complicates 1% - 22% of endoscopic retrograde cholangiopancreatography procedures. The study aims were to develop a reproducible animal model of post-ERCP pancreatitis (PEP), and investigate the impact of endoscopic technique on severity of PEP.

PATIENTS AND METHODS

ERCP was carried out in six male hound dogs. Pancreatitis was induced by one of three escalating methods: 1) pancreatic acinarization with 20 - 30 mL of contrast; 2) acinarization + ductal balloon occlusion + sphincterotomy; 3) acinarization + intraductal synthetic bile injection + ductal balloon occlusion + sphincterotomy. Dogs 5 and 6 received a pancreatic stent. Necropsy was performed on postoperative day 5. All pancreatic specimens were graded by two blinded pathologists according to a validated scoring system. All dogs were compared with three control dogs.

RESULTS

Dogs 1 - 4 developed clinical pancreatitis and hyperamylasemia (11 736 vs. 722 U/L, P = 0.02). Total injury scores were significantly elevated compared with controls (6.85 vs. 1.06, P = 0.004). There was significant increase in acinar cell necrosis (0.86 vs. 0.06, P = < 0.001), and all other categories (except fibrosis) demonstrated elevated injury scores . Dogs 5 and 6 developed clinical pancreatitis without significant hyperamylasemia; total injury scores were elevated compared with controls (4.83 vs. 1.06, P = 0.01), but lower than in Dogs 1 - 4 (4.83 vs. 6.85, P = 0.25). There was escalating severity of pancreatic injury from Dogs 1 to 4 correlating with the method of endoscopic injury used.

CONCLUSION

Severity of PEP is directly proportional to invasiveness of endoscopic intervention. Pancreatic acinarization, even without balloon occlusion and sphincterotomy, can be used as a reliable animal model for future studies investigating therapy and prevention of disease.

Preliminary pneumoperitoneum facilitates transgastric access into the peritoneal cavity for natural orifice transluminal endoscopic surgery: a pilot study in a live porcine model

BACKGROUND AND STUDY AIMS

Safe entrance into the peritoneal cavity through the gastric wall is paramount for the successful clinical introduction of natural orifice transluminal endoscopic surgery (NOTES). The aim of the study was to develop alternative safe transgastric access to the peritoneal cavity.

PATIENTS AND METHODS

We performed 11 survival experiments on 50-kg pigs. In sterile conditions, the abdominal wall was punctured with a Veress needle. The peritoneal cavity was insufflated with 2 L carbon dioxide (CO (2)). A sterile endoscope was introduced into the stomach through a sterile overtube; the gastric wall was punctured with a needle-knife; after balloon dilation of the puncture site, the endoscope was advanced into the peritoneal cavity. Peritoneoscopy with biopsies from abdominal wall, liver and omentum, was performed. The endoscope was withdrawn into the stomach. The animals were kept alive for 2 weeks and repeat endoscopy was followed by necropsy.

RESULTS

The pneumoperitoneum, easily created with the Veress needle, lifted the abdominal wall and made a CO (2)-filled space between the stomach and adjacent organs, facilitating gastric wall puncture and advancement of the endoscope into the peritoneal cavity. There were no hemodynamic changes or immediate or delayed complications related to pneumoperitoneum, transgastric access, or intraperitoneal manipulations. Follow-up endoscopy and necropsy revealed no problems or complications inside the stomach or peritoneal cavity.

CONCLUSIONS

Creation of a preliminary pneumoperitoneum with a Veress needle facilitates gastric wall puncture and entrance into the peritoneal cavity without injury to adjacent organs, and can improve the safety of NOTES.

The utility of contrast-enhanced endoscopic ultrasound in monitoring ethanol-induced pancreatic tissue ablation: a pilot study in a porcine model

BACKGROUND AND STUDY AIMS

Pancreatic ablation is gaining popularity for the treatment of focal pancreatic lesions. The aim of our study was to evaluate local effects of intrapancreatic alcohol injection and the utility of contrast-enhanced endoscopic ultrasound (EUS) for its monitoring in a porcine model.

METHODS

We performed four survival experiments on 50-kg pigs. Under linear EUS guidance, 0.5 mL of 50% ethanol plus purified carbon particle solution (GI Spot) was injected into the pancreatic body to create a focal area of pancreatic necrosis. The animals survived for 24-48 hours (pigs # 1, # 2, and # 3) and 7 days (pig # 4). EUS was then repeated with and without perflutren lipid microspheres (Definity) administration through the peripheral vein. Standard and microsphere-enhanced images of the pancreas were compared. Afterwards the animals were euthanized for necropsy.

RESULTS

Alcohol injection caused focal pancreatic necrosis, which was barely seen by standard EUS as a subtle hypoechoic lesion 1 cm in diameter. Color and power Doppler EUS of this region did not reveal any blood flow. After intravenous injection of microspheres, color Doppler EUS revealed marked contrast enhancement of normal pancreatic parenchyma with a clearly delineated avascular alcohol-treated area, which on postmortem examination corresponded to the discrete necrotic area marked with carbon particles.

CONCLUSIONS

EUS-guided alcohol injection consistently causes focal areas of pancreatic necrosis. Contrast-enhanced EUS with microspheres improves visualization of altered pancreatic vascular perfusion and can be used to facilitate detection of small pancreatic lesions and its follow-up post-ablation.

Is blood the ideal submucosal cushioning agent? A comparative study in a porcine model

BACKGROUND AND STUDY AIMS

Creation of a submucosal cushion before endoscopic mucosal resection (EMR) significantly reduces perforation risk. We evaluated six solutions as cushioning agents in live pigs.

MATERIAL AND METHODS

5 ml of normal saline, normal saline plus epinephrine, albumin 12.5 %, albumin 25 %, hydroxypropyl methylcellulose, and the pig's own whole blood were endoscopically injected into the porcine esophageal submucosa. Blood was obtained from a peripheral vein immediately before injection. Injections were made every 4 cm from the gastroesophageal junction. The time from completion of the injection to disappearance of the cushion was recorded. Endoscopy was repeated at 48 hours post injection. Two EMRs were performed after blood injection. Statistical analysis employed one-way analysis of variance followed by pairwise T test comparisons using the Bonferroni correction.

RESULTS

Five animal experiments were completed. The mean time to dissipation of the submucosal cushion was shortest for saline plus epinephrine sites (2.87 minutes, SD 2.21) followed by the saline (4.8 minutes, SD 1.56), albumin 12.5 % (5.68 minutes, SD 3.48), albumin 25 % (7.83 minutes, SD 2.02), hydroxypropyl methylcellulose (9.77 minutes, SD 1.55), and blood sites (38.6 minutes, SD 6.07). Injection of blood resulted in significantly longer mucosal elevation than any other solution ( P < 0.0007). Blood from the cushion did not hamper visualization and facilitated EMR.

CONCLUSION

Blood produces the most durable cushion compared with standard agents, also having the advantages of being readily available and without cost. Albumin 25 % provides as durable a cushion as hydroxypropyl methylcellulose.

Irradiation Time and Ablation Rate of Enamel in Contact and Non-contact Irradiation with Er:YAG Laser

OBJECTIVE

The relationship between changes in ablation rate of enamel with irradiation time was investigated to find the most effective irradiation time for tooth ablation by Er:YAG laser.

BACKGROUND DATA

Previous studies have shown that the Er:YAG laser has the ability to ablate tooth material effectively, but that the efficiency and effectiveness of ablation are determined by various parameters such as energy, pulse frequency, the amount of water, and irradiation time.

METHODS

Contact and non-contact irradiation of the Er:YAG laser were carried out respectively for 1, 3, 5, and 7 s on the enamel surface of each specimen using a combination of a 400 mJ/pulse at 20 Hz and water flow rate of 6.75 mL/min, and quantitative measurements using a mass balance were performed to compare the resulting ablation rates.

RESULTS

The ablation weight, by taking the mean of both contact and non-contact irradiation, generally increased with irradiation exposure time, but no significant increases in ablation were seen in specimens that had been exposed for > 3 s in either the contact or non-contact irradiation group. Results in the non-contact irradiation group indicated superior ablation of enamel compared to that in the contact irradiation group.

CONCLUSION

Irradiation exposure of < or = 3 s per application of laser beam is recommended to ablate enamel effectively in both non-contact and contact irradiation.

Selegiline potentiates the effects of EGb 761 in response to ischemic brain injury

We evaluated whether combined treatment with selegiline, a selective MAO-B inhibitor, and EGb 761, a standard extract of Ginkgo biloba, has synergistic effects against ischemic reperfusion injury (IRI) in gerbils. Interestingly, we observed that pretreatment with EGb 761 significantly attenuated selegiline-induced hyperactivity. This finding paralleled striatal fos-related antigen immunoreactivity (FRA-IR) in mice. Four minutes of bilateral carotid artery occlusion caused substantial cell loss in the CA1 of the hippocampus 5 days post-ischemic insult. Pretreatment with EGb 761, with or without selegiline, significantly attenuated this neuronal loss. Combined treatment with EGb 761 plus selegiline was more efficacious in preventing this loss. Synaptosomal formations of protein carbonyl, lipid peroxidation (malondialdehyde (MDA) + 4-hydroxyalkenal (4-HDA)), and reactive oxygen species (ROS) in the hippocampus remained elevated 5 days post-ischemic insult. The antioxidant effects appeared to be most significant in the group treated with EGb 761 plus selegiline. This combined treatment produced more significant attenuation of IRI-induced alterations in intramitochondrial calcium accumulation, the mitochondrial transmembrane potential, and mitochondrial Mn-superoxide dismutase-like immunoreactivity (Mn-SOD-IR) than either treatment alone. Our results suggest that co-administration of EGb 761 and selegiline produces significant neuroprotective effects via suppression of oxidative stress and mitochondrial dysfunction without affecting neurological function.

Hydrocele of the canal of Nuck in a girl: ultrasound and MR appearance

Hydrocele of the canal of Nuck is a rare condition in females. A small evagination of parietal peritoneum forms the canal of Nuck. Failure of complete obliteration of the canal results in either an indirect inguinal hernia or a hydrocele of the canal of Nuck. We present a case in a 7-year-old girl. On ultrasound, there was a comma-shaped cyst with the tail directed cranially toward the inguinal canal. The cyst had no internal echoes and demonstrated increased through transmission. Coronal and axial MR showed a thin walled cystic mass.

Oxidative damage causes formation of lipofuscin-like substances in the hippocampus of the senescence-accelerated mouse after kainate treatment

We have demonstrated that seizures induced by kainic acid (KA) are, at least in part, mediated via oxidative stress in rats [Life. Sci. 61 (1997) PL373; Brain Res. 853 (2000) 215; Brain Res. 874 (2000) 15; Neurosci. Lett. 281 (2000) 65]. In order to extend our findings, we employed the rodent aging model in this study. After KA treatments (once a day for 5 days; 20,20,20,20 and 40 mg/kg, i.p.), several parameters reflecting neurotoxic behaviors, oxidative stress [malondialdehyde (MDA) and protein carbonyl] and aging (lipofuscin-like substances) were compared between senile-prone (P8) and resistant (R1) strains of 9-month-old male senescence-accelerated mice (SAM). KA-induced neurotoxic signs as shown by mortality and seizure activity were more accentuated in the SAM-P8 than in the SAM-R1. Levels of MDA and carbonyl are consistently higher in the hippocampus of SAM-P8 than that of SAM-R1. Significant increases in the values of MDA and carbonyl were observed 4 h or 2 days after the final KA administration. This finding was more pronounced in the SAM-P8 than in the SAM-R1. Although a significant loss of hippocampal neurons was observed 7 days post-KA, at this time the MDA and carbonyl content had returned to near control levels. In contrast, fluorescent lipofuscin-like substances and lipofuscin granules were significantly increased 7 days after KA treatments. Therefore, our data suggests that mice in the senescence model are more susceptible to KA-induced seizures/oxidative damage, and that oxidative damage could be one of the casual factors in the accumulation of lipofuscin.

Prenatal exposure to magnetic field increases dopamine levels in the striatum of offspring

1. The putative effects of prenatal exposure to magnetic field (MF) have recently received much interest. In the present study, mice were exposed to a MF of 50 mT during gestation (0-19 days). 2. After the exposure was terminated, mothers and offspring were returned to normal laboratory conditions. We then determined changes in striatal levels of dopamine (DA) and its metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) in the offspring. 3. Our results indicate that prenatal exposure to MF increases levels of DA and DOPAC in the striatum at 4, 8 and 12 weeks postnatally.

Carbetapentane attenuates kainate-induced seizures via sigma-1 receptor modulation

We examined the effects of a non-opioid antitussive, carbetapentane (CB) on kainic acid (KA)-induced neurotoxicity in rats. KA administration (10 mg/kg, i.p.) produced robust behavioral convulsions lasting 4 to 5 h. CB (12.5 and 25 mg/kg. i.p.) pretreatment consistently and in a dose-dependent manner reduced the KA-induced seizures, mortality, and marked loss of cells in regions CA1 and CA3 of the hippocampus. Consistently, CB pretreatment also significantly attenuated the KA-induced increase in Fos-related antigen immunoreactivity in the hippocampus. In contrast, pretreatment with the sigma-1 receptor antagonist BD1047 (1 and 2 mg/kg, i.p.) blocked, in a dose-related manner, the neuroprotection afforded by CB. These results suggest that CB provides neuroprotection against KA insult via sigma-1 receptor modulation.

Anticonvulsant effects of new morphinan derivatives

We synthesized a series of compounds that are modified in positions 3 and 17 of the morphinan ring system, with the intention of developing ideal anticonvulsant agents. We examined the effects of these compounds on kainic acid (KA)-induced seizures, and on locomotor patterns in rats. We found that compounds 5, 6, and 8 exhibit novel anticonvulsant effects, with negligible psychotropic effects.

Dextromethorphan affects cocaine-mediated behavioral pattern in parallel with a long-lasting Fos-related antigen-immunoreactivity

In order to understand the underlying mechanisms responsible for the behaviors mediated by dextromethorphan (DM), we examined the effects of DM on locomotor activity and locomotor patterns in mice, and Fos-related antigen immunoreactivity (FRA-IR) of mouse brain following repeated administration of cocaine. Combined treatments (30 min prior to each cocaine administration) with DM dose-dependently decreased locomotor activity for high doses of cocaine (20 mg/kg, i.p./day x 7). DM combinations did not significantly affect hyperactivity for 10 mg cocaine/kg, i.p./day x 7. In contrast, combined treatments with DM increased the locomotor activity for 5 mg cocaine/kg, i.p./day x 7. These results were consistent with alterations in marginal activity. Repeated administration with cocaine or DM increased FRA-IR in the nucleus accumbens (NAc) and striatum which lasted for at least 7 days. Our results suggest that DM exhibits biphasic effects on the locomotor stimulation induced by cocaine, and that locomotor activities are in parallel with FRA-IR of the striatal complex. However, the role of FRA-IR regulated by DM or/and cocaine remains to be further determined.