Electrosprayable Levan-Coated Nanoclusters and Ultrasound-Responsive Drug Delivery for Cancer Therapy

In this study, we synthesized levan shell hydrophobic silica nanoclusters encapsulating doxorubicin (L-HSi-Dox) and evaluated their potential as ultrasound-responsive drug delivery systems for cancer treatment. L-HSi-Dox nanoclusters were successfully fabricated by integrating a hydrophobic silica nanoparticle-doxorubicin complex as the core and an amphiphilic levan carbohydrate polymer as the shell by using an electrospray technique. Characterization analyses confirmed the stability, size, and composition of the nanoclusters. In particular, the nanoclusters exhibited a controlled release of Dox under aqueous conditions, demonstrating their potential as efficient drug carriers. The levanic groups of the nanoclusters enhanced the targeted delivery of Dox to specific cancer cells. Furthermore, the synergism between the nanoclusters and ultrasound effectively reduced cell viability and induced cell death, particularly in the GLUT5-overexpressing MDA-MB-231 cells. In a tumor xenograft mouse model, treatment with the nanoclusters and ultrasound significantly reduced the tumor volume and weight without affecting the body weight. Collectively, these results highlight the potential of the L-HSi-Dox nanoclusters and ultrasound as promising drug delivery systems with an enhanced therapeutic efficacy for biomedical applications.

QTLs and Candidate Genes for Seed Protein Content in Two Recombinant Inbred Line Populations of Soybean

This study aimed to discover the quantitative trait loci (QTL) associated with a high seed protein content in soybean and unravel the potential candidate genes. We developed two recombinant inbred line populations: YS and SI, by crossing Saedanbaek (high protein) with YS2035-B-91-1-B-1 (low protein) and Saedanbaek with Ilmi (low protein), respectively, and evaluated the protein content for three consecutive years. Using single-nucleotide polymorphism (SNP)-marker-based linkage maps, four QTLs were located on chromosomes 15, 18, and 20 with high logarithm of odds values (5.9-55.0), contributing 5.5-66.0% phenotypic variance. In all three experimental years, qPSD20-1 and qPSD20-2 were stable and identified in overlapping positions in the YS and SI populations, respectively. Additionally, novel QTLs were identified on chromosomes 15 and 18. Considering the allelic sequence variation between parental lines, 28 annotated genes related to soybean seed protein-including starch, lipid, and fatty acid biosynthesis-related genes-were identified within the QTL regions. These genes could potentially affect protein accumulation during seed development, as well as sucrose and oil metabolism. Overall, this study offers insights into the genetic mechanisms underlying a high soybean protein content. The identified potential candidate genes can aid marker-assisted selection for developing soybean lines with an increased protein content.

Choroidal detachment and hypotony following selective laser trabeculoplasty: a case report

BACKGROUND

Selective laser trabeculoplasty (SLT) is relatively safe and effective in lowering intraocular pressure (IOP). However, although rare, complications can occur after SLT. This report describes a patient with choroidal detachment due to hypotony following SLT without anterior chamber (AC) inflammation.

CASE PRESENTATION

A 67-year-old man was referred for elevated IOP in his left eye with advanced glaucomatous visual field loss. He had previously been diagnosed with idiopathic uveitic glaucoma in the left eye, for which he underwent laser iridotomy, trabeculectomy, and cataract surgery. At the first visit, the IOP of his left eye measured by Goldmann tonometry was 28 mmHg despite maximally tolerated medical treatment. SLT was performed in his left eye, resulting in an IOP of 7 mmHg 7 days later. At 3 weeks post-procedure, the patient experienced ocular pain and decreased visual acuity in his left eye. Slit-lamp examination revealed deep anterior chamber depth and no inflammation reaction, but the IOP in his left eye was 4 mmHg, and both fundus and B-scan ultrasonography showed serous choroidal detachment. All anti-glaucoma agents were stopped, and the patient was started on treatment with oral prednisolone and cyclopentolate eye drops. Three weeks later, choroidal detachment had resolved and the IOP in his left eye had stabilized at 8 mmHg. Follow-up 3 months later showed that the IOP in his left eye remained stable.

CONCLUSIONS

Choroidal detachment-related hypotony is a rare complication of SLT. This possible complication following SLT should be informed to the patients and considered when performing the procedure.

Transient Cortical Blindness Following Cervical Transforaminal Epidural Injection

Purpose: To report a case of transient cortical blindness following cervical transforaminal epidural injection.Case summary: A 58-year-old diabetic and hypertensive male was referred to the ophthalmology department with sudden-onset bilateral visual disturbances after cervical transforaminal epidural injection for neck pain. During the procedure, an intravascular contrast medium was injected into the left vertebral artery. Immediately after the injection, the patient complained of bilateral visual disturbances, mild headache, and dizziness. Twelve hours after the procedure, his visual acuity was reduced to hand motion perception in both eyes. Anterior segment and fundus examinations were unremarkable. Pupillary light reflexes and extraocular muscle movements were normal. Brain magnetic resonance imaging, magnetic resonance angiography, and fluorescein angiography showed no significant findings. There were no other neurological abnormalities. The patient was treated conservatively with intravenous dexamethasone and nimodipine based on a provisional diagnosis of transient cortical blindness. The symptoms gradually improved 2 days after the procedure; visual acuity recovered to 20/20 by the third day.Conclusions: Although contrast-induced transient cortical blindness is rare, it should be considered in patients with bilateral visual loss after transforaminal epidural injection. It is a benign and reversible condition but requires a prompt diagnosis.

Glycan chip based on structure-switchable DNA linker for on-chip biosynthesis of cancer-associated complex glycans

On-chip glycan biosynthesis is an effective strategy for preparing useful complex glycan sources and for preparing glycan-involved applications simultaneously. However, current methods have some limitations when analyzing biosynthesized glycans and optimizing enzymatic reactions, which could result in undefined glycan structures on a surface, leading to unequal and unreliable results. In this work, a glycan chip is developed by introducing a pH-responsive i-motif DNA linker to control the immobilization and isolation of glycans on chip surfaces in a pH-dependent manner. On-chip enzymatic glycosylations are optimized for uniform biosynthesis of cancer-associated Globo H hexasaccharide and its related complex glycans through stepwise quantitative analyses of isolated products from the surface. Successful interaction analyses of the anti-Globo H antibody and MCF-7 breast cancer cells with on-chip biosynthesized Globo H-related glycans demonstrate the feasibility of the structure-switchable DNA linker-based glycan chip platform for on-chip complex glycan biosynthesis and glycan-involved applications.

Electrohydrodynamic Sprayable Amphiphilic Polysaccharide-Clasped Nanoscale Self-Assembly for In Vivo Imaging

The work presented in this report demonstrates that amphiphilic polysaccharide-clasped self-assembly (Amp-SA) with nanometer size, encapsulating hydrophobic nanoparticles (NPs) can be generated via electrohydrodynamic spraying. It is observed that the formation of hydrophobic NP-encapsulated Amp-SA is dependent on the surface chemistry of NPs. The citrate-coated magnetic NPs (MNPs-Cit) were also prepared and compared. The hydrophobic magnetic NP-encapsulated Amp-SA (Amp-SA-M) exhibited around 2.7-2.8-fold higher values in r₂ relaxivity than that of MNPs-Cit. In addition, the resulting Amp-SA-M achieved ∼17.2-fold higher values in r₂/r₁ ratios than MNPs-Cit. The enhanced performances in magnetic transverse (r₂) relaxivity and r₂/r₁ ratio as well as the in vivo behavior of Amp-SA-M suggest the potential of Amp-SA-M as a promising MRI nanoprobe. This approach based on the nature-originated amphiphilic biopolymers may provide a novel insight into electrohydrodynamic techniques that have the ability to create various nanostructures, encapsulating high-quality hydrophobic nanomaterials for applications in diverse biotechnology.

Polysaccharide-Hydrophobic Nanoparticle Hybrid Nanoclusters for Enhanced Performance in Magnetic Resonance/Photoacoustic Imaging

Polysaccharide-nanoparticle (NP) hybrid nanoclusters have great potential to revitalize diverse bioapplications; however, fabricating polysaccharide-based hybrid nanoclusters composed of high-quality NPs generated in the organic phase remains a challenge. Here, using calcium alginate as a polysaccharide/tetramethylammonium hydroxide (TMAOH) combination, we report a novel approach to the design of alginate-hydrophobic magnetic-plasmonic core-shell (MPCS) NP hybrid nanoclusters (A-MPCS HNCs). Furthermore, we observe the dependence of the formation of A-MPCS HNCs on the TMAOH concentration. The enhanced performance in both magnetic resonance r₂ relaxivity and photoacoustic (PA) signals and the biocompatibility/bioactivity as well as the in vivo performance of A-MPCS HNCs shows them to be a promising magnetic resonance/photoacoustic dual-mode imaging agent. Our strategy could open doors to the use of other precious high-quality nanomaterials created in the organic phase via well-established synthetic chemistry in the design of alginate-hydrophobic nanomaterial hybrid nanoclusters, giving rise to novel and multifarious bioapplications.

Clinical usefulness of two-phase 18F-sodium-fluoride (18F-NaF) bone PET/CT for evaluating treatment response of bone metastases from breast cancer: Case report

We report the case of a breast cancer patient in whom a two-phase ¹⁸F-sodium-fluoride (¹⁸F-NaF) bone PET/CT was useful for detecting hidden bone metastases and assessing treatment response. The patient underwent a two-phase bone PET/CT to evaluate a newly developed lesion found on bone scintigraphy following surgery. In the perfusion and bone phase PET/CT images, focally increased perfusion and bony uptake were found in the sacrum and L5 vertebra, suggesting bone metastases of breast cancer. Therefore, the patient subsequently underwent palliative treatment. In another twoPET/CT studies (each including two-phase bone images) performed after 3and 6months of follow-up, the perfusion phase images showed an improvement of the lesion uptake more clearly than in the bone phase images in the visual and semi-quantitative analyses, and thus the perfusion phase images were more useful for clarifying the treatment response earlier than the bone phase images. This is the first case showing the clinical usefulness of ¹⁸F-NaF bone PET/CT with the perfusion imaging technique for evaluating bone metastases and the therapeutic response of metastatic bone lesions.

On-chip biosynthesis of GM1 pentasaccharide-related complex glycans

A novel strategy for on-chip enzymatic glycosylation of complex glycans and direct analysis of glycan-related interactions is reported.

Surface Design of Eu-Doped Iron Oxide Nanoparticles for Tuning the Magnetic Relaxivity

Relaxivity tuning of nanomaterials with the intrinsic T₁- T₂ dual-contrast ability has great potential for MRI applications. Until now, the relaxivity tuning of T₁ and T₂ dual-modal MRI nanoprobes has been accomplished through the dopant, size, and morphology of the nanoprobes, leaving room for bioapplications. However, a surface engineering method for the relaxivity tuning was seldom reported. Here, we report the novel relaxivity tuning method based on the surface engineering of dual-mode T₁- T₂ MRI nanoprobes (DMNPs), along with protein interaction monitoring with the DMNPs as a potential biosensor application. Core nanoparticles (NPs) of europium-doped iron oxide (EuIO) are prepared by a thermal decomposition method. As surface materials, citrate (Cit), alendronate (Ale), and poly(maleic anhydride- alt-1-octadecene)/poly(ethylene glycol) (PP) are employed for the relaxivity tuning of the NPs based on surface engineering, resulting in EuIO-Cit, EuIO-Ale, and EuIO-PP, respectively. The key achievement of the current study is that the surface materials of the DMNP have significant impacts on the r₁ and r₂ relaxivities. The correlation between the hydrophobicity of the surface material and longitudinal relaxivity ( r₁) of EuIO NPs presents an exponential decay feature. The r₁ relaxivity of EuIO-Cit is 13.2-fold higher than that of EuIO-PP. EuIO can act as T₁- T₂ dual-modal (EuIO-Cit) or T₂-dominated MRI contrast agents (EuIO-PP) depending on the surface engineering. The feasibility of using the resulting nanosystem as a sensor for environmental changes, such as albumin interaction, was also explored. The albumin interaction on the DMNP shows both T₁ and T₂ relaxation time changes as mutually confirmative information. The relaxivity tuning approach based on the surface engineering may provide an insightful strategy for bioapplications of DMNPs and give a fresh impetus for the development of novel stimuli-responsive MRI nanoplatforms with T₁ and T₂ dual-modality for various biomedical applications.

Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites

The topotactic phase transition in SrCoO_x (x = 2.5–3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO_2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO₃ that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO_2.5, however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoO_x is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.

Survival of Verwey transition in gadolinium-doped ultrasmall magnetite nanoparticles

We have demonstrated that the Verwey transition, which is highly sensitive to impurities, survives in anisotropic Gd-doped magnetite nanoparticles. Transmission electron microscopy analysis shows that the nanoparticles are uniformly distributed. X-ray photoelectron spectroscopy and EDS mapping analysis confirm Gd-doping on the nanoparticles. The Verwey transition of the Gd-doped magnetite nanoparticles is robust and the temperature dependence of the magnetic moment (zero field cooling and field cooling) shows the same behaviour as that of the Verwey transition in bulk magnetite, at a lower transition temperature (∼110 K). In addition, irregularly shaped nanoparticles do not show the Verwey transition whereas square-shaped nanoparticles show the transition. Mössbauer spectral analysis shows that the slope of the magnetic hyperfine field and the electric quadrupole splitting change at the same temperature, meaning that the Verwey transition occurs at ∼110 K. These results would provide new insights into understanding the Verwey transition in nano-sized materials.

Use of supplemental anti-HBc testing of donors showing non-discriminating reactive results in multiplex nucleic acid testing

BACKGROUND AND OBJECTIVES

The Korean Red Cross began nucleic acid amplification testing (NAT) for HIV and HCV in February 2005, and added HBV NAT beginning in June 2012. The current NAT system utilizes a multiplex assay for simultaneous detection of HBV DNA, HCV RNA and HIV-1 RNA. For samples that are reactive in the multiplex assay, we do specific tests for each virus. However, there have been cases of non-discriminated reactive (NDR) results which appear to be the result of non-specific reactions or cross-contamination, although some cases are considered to arise from the presence of low levels of HBV DNA due to occult hepatitis B infection.

MATERIALS AND METHODS

We examined the incidence of NDR results in previous donations of some NAT-reactive donors. Additionally, for those donors with NDR results, we performed an HBV core antibody (anti-HBc) assay.

RESULTS

From November 2015 to March 2016, there were 408 NAT-reactive donors. Of these, nineteen HBV NAT-reactive donors showed a history of NDR results in the past donations. Seven donors showed NDR results more than once. Of 771 NDR donors, 362 (47·0%) were anti-HBc reactive.

CONCLUSION

The NDR donors had a substantially higher rate of anti-HBc reactivity than other blood donors indicating that some with anti-HBc reactivity represent donors with occult HBV. Therefore, the incorporation of an anti-HBc testing for NDR donors could improve blood safety testing for the Korean Red Cross.

Recombinant mussel proximal thread matrix protein promotes osteoblast cell adhesion and proliferation

Background

von Willebrand factor (VWF) is a key load bearing domain for mamalian cell adhesion by binding various macromolecular ligands in extracellular matrix such as, collagens, elastin, and glycosaminoglycans. Interestingly, vWF like domains are also commonly found in load bearing systems of marine organisms such as in underwater adhesive of mussel and sea star, and nacre of marine abalone, and play a critical load bearing function. Recently, Proximal Thread Matrix Protein1 (PTMP1) in mussel composed of two vWF type A like domains has characterized and it is known to bind both mussel collagens and mammalian collagens.

Results

Here, we cloned and mass produced a recombinant PTMP1 from E. coli system after switching all the minor codons to the major codons of E. coli. Recombinant PTMP1 has an ability to enhance mouse osteoblast cell adhesion, spreading, and cell proliferation. In addition, PTMP1 showed vWF-like properties as promoting collagen expression as well as binding to collagen type I, subsequently enhanced cell viability. Consequently, we found that recombinant PTMP1 acts as a vWF domain by mediating cell adhesion, spreading, proliferation, and formation of actin cytoskeleton.

Conclusions

This study suggests that both mammalian cell adhesion and marine underwater adhesion exploits a strong vWF-collagen interaction for successful wet adhesion. In addition, vWF like domains containing proteins including PTMP1 have a great potential for tissue engineering and the development of biomedical adhesives as a component for extra-cellular matrix.

Relationship between tinnitus and suicidal behaviour in Korean men and women: a cross-sectional study

OBJECTIVES

This study investigated the prevalence of suicidal ideation and behaviour in a representative sample of South Koreans with or without tinnitus.

DESIGN

A cross-sectional study.

SETTING

Based on data from the 2010 to 2012 Korean National Health and Nutrition Examination Survey (KNHANES).

PARTICIPANTS

The study included 17 446 Korean individuals.

MAIN OUTCOME MEASURES

Participants provided demographic, socio-economic and behavioural information, as well as responses to questionnaires assessing the presence and severity of tinnitus, mental health status regarding stress, depression, and suicidal ideation and attempts. In the univariate analysis, the Rao-Scott chi-square test and logistic regression analysis were used to test the association between tinnitus and risk factors. Simple and multiple linear regression analyses were used to examine the association between tinnitus and mental status.

RESULTS

A total of 20.9% and 1.2% of participants with tinnitus, and 12.2% and 0.6% of those without, reported suicidal ideation and attempts, respectively (P < 0.0001 and P = 0.001). Participants reporting suicide attempts showed a higher proportion of severe annoying (6.0%) and irritating (11.8%) tinnitus than those with suicidal ideation (1.4% and 10.2%, respectively). Risks for experiencing tinnitus were significantly associated with suicidal ideation and attempts after adjusting for confounding variables.

CONCLUSION

This study has important implications for enhanced screening and evaluation of mental health status and suicidal ideation/behaviour among tinnitus patients.

Retinoic Acid as a Radiosensitizer on the Head and Neck Squamous Cell Carcinoma Cell Lines

PURPOSE

Retinoic acid is a substance that has previously been reported to increase radiosensitivity, but at concentrations likely to inhibit cell growth or to induce celluar differentiation. We choose head and neck cancer cell lines to investigate the role of retinoic acid as a radiosensitizer and to elucidate the mechanism through the changes in the expression of retinoid receptors and squamous cell differentiation marker.

MATERIALS AND METHODS

Three cell lines (PCI-50, SqCC/ Y1 and UMSCC-11B) were used. 7-AAD staining for apoptosis and Western blot analysis for RAR-alpha, beta, gamma, RXR-alpha, beta, gamma and involucrin were performed after various treatments (control, beta-all-trans-retinoic acid (t-RA) only (10 6 M), radiation only (3 Gy), radiation with t-RA).

RESULTS

The synergistic radiosensitivity effect of t-RA was seen only radioresistant UMSCC-11B cell line. Expression of RAR-beta was induced by t-RA in maily UMSCC- 11B cell line. RAR-alpha,gamma, and RXR-alpha, beta, gamma expression were not changed in all cell lines tested. Expression of involucrin was inhibited by t-RA in PCI-50 cell line but other two cell lines were not changed by t-RA treatment.

CONCLUSION

We found that only radioresistant cell line (UMSCC-11B) showed synergistic radiosensitivity effect by t-RA and this mechanism may be through RAR-beta expression induction.

The siRNA cocktail targeting interleukin 10 receptor and transforming growth factor-β receptor on dendritic cells potentiates tumour antigen-specific CD8(+) T cell immunity

Dendritic cells (DCs) are promising therapeutic agents in the field of cancer immunotherapy due to their intrinsic immune-priming capacity. The potency of DCs, however, is readily attenuated immediately after their administration in patients as tumours and various immune cells, including DCs, produce various immunosuppressive factors such as interleukin (IL)-10 and transforming growth factor (TGF)-β that hamper the function of DCs. In this study, we used small interfering RNA (siRNA) to silence the expression of endogenous molecules in DCs, which can sense immunosuppressive factors. Among the siRNAs targeting various immunosuppressive molecules, we observed that DCs transfected with siRNA targeting IL-10 receptor alpha (siIL-10RA) initiated the strongest antigen-specific CD8(+) T cell immune responses. The potency of siIL-10RA was enhanced further by combining it with siRNA targeting TGF-β receptor (siTGF-βR), which was the next best option during the screening of this study, or the previously selected immunoadjuvant siRNA targeting phosphatase and tensin homologue deleted on chromosome 10 (PTEN) or Bcl-2-like protein 11 (BIM). In the midst of sorting out the siRNA cocktails, the cocktail of siIL-10RA and siTGF-βR generated the strongest antigen-specific CD8(+) T cell immunity. Concordantly, the knock-down of both IL-10RA and TGF-βR in DCs induced the strongest anti-tumour effects in the TC-1 P0 tumour model, a cervical cancer model expressing the human papillomavirus (HPV)-16 E7 antigen, and even in the immune-resistant TC-1 (P3) tumour model that secretes more IL-10 and TGF-β than the parental tumour cells (TC-1 P0). These results provide the groundwork for future clinical development of the siRNA cocktail-mediated strategy by co-targeting immunosuppressive molecules to enhance the potency of DC-based vaccines.

A nano-scale probing system with a gold nano-dot array for measurement of a single biomolecular interaction force

A new nano-scale probing system was proposed and developed to measure and analyze the interaction force between biomolecules at the single molecular level.

Surface-independent antibacterial coating using silver nanoparticle-generating engineered mussel glue

During implant surgeries, antibacterial agents are needed to prevent bacterial infections, which can cause the formation of biofilms between implanted materials and tissue. Mussel adhesive proteins (MAPs) derived from marine mussels are bioadhesives that show strong adhesion and coating ability on various surfaces even in wet environment. Here, we proposed a novel surface-independent antibacterial coating strategy based on the fusion of MAP to a silver-binding peptide, which can synthesize silver nanoparticles having broad antibacterial activity. This sticky recombinant fusion protein enabled the efficient coating on target surface and the easy generation of silver nanoparticles on the coated-surface under mild condition. The biosynthesized silver nanoparticles showed excellent antibacterial efficacy against both Gram-positive and Gram-negative bacteria and also revealed good cytocompatibility with mammalian cells. In this coating strategy, MAP-silver binding peptide fusion proteins provide hybrid environment incorporating inorganic silver nanoparticle and simultaneously mediate the interaction of silver nanoparticle with surroundings. Moreover, the silver nanoparticles were fully synthesized on various surfaces including metal, plastic, and glass by a simple, surface-independent coating manner, and they were also successfully synthesized on a nanofiber surface fabricated by electrospinning of the fusion protein. Thus, this facile surface-independent silver nanoparticle-generating antibacterial coating has great potential to be used for the prevention of bacterial infection in diverse biomedical fields.

Association of aldehyde dehydrogenase 1 expression and biologically aggressive features in breast cancer

Aldehyde dehydrogenase 1 (ALDH1) has been regarded as a breast cancer stem cell marker. Several studies have reported that ALDH1 expression is associated with poor prognosis in breast cancer. We aimed, therefore, to determine the prognostic value of ALDH1 expression and its association with several biomarkers in breast cancer tissue using immunohistochemistry. Furthermore, we investigated the characteristics of and differences between cellular and stromal expression of ALDH1. We performed tissue microarray (TMA) analysis of 425 breast cancer tissue samples collected during surgery. Immunohistochemical staining was then performed to measure the expression of ALDH1 and other breast cancer biomarkers. Statistical analysis of the relationship between ALDH1 expression and clinicopathologic characteristics was performed for 390 TMA samples. We found that ALDH1 was expressed in 71 cases (18.2%) in the tumor cells and/or stroma. Of these cases, 38 (9.7%) showed ALDH1 expression in tumor cells and 38 (9.7%) showed ALDH1 expression in the stroma. ALDH1 expression was significantly associated with markers of a poor prognosis, such as young age, estrogen receptor negativity, progesterone receptor negativity, a high histological grade, and a high Ki-67 index. However, ALDH1 expression was not associated with p53, transforming growth factor-beta, Gli-1, YKL-40, or sonic hedgehog expression status. With regard to the expression site, the clinical characteristics did not differ between cases of cellular expression and those of stromal expression. However, ALDH1 expression in tumor cells was correlated with hormone receptor status, histological grade, molecular subtype, epidermal growth factor receptor expression status, and cytokeratin 5/6 expression status while stromal expression of ALDH1 was only correlated with hormone receptor status. Overall, these findings suggest that ALDH1 expression in tumor tissue is associated with a biologically aggressive phenotype.

KEYWORDS

ALDH1, biologically aggressive, breast cancer.

Relationship between early postoperative C-reactive protein elevation and long-term postoperative major adverse cardiovascular and cerebral events in patients undergoing off-pump coronary artery bypass graft surgery: a retrospective study

BACKGROUND

Inflammation plays a key role in the pathogenesis of vascular occlusive diseases, such as myocardial infarction and stroke. Additionally, these conditions are predicted by C-reactive protein (CRP), a general inflammation marker. We hypothesized that the inflammation induced by surgery itself augments vascular occlusive disease. We retrospectively evaluated the relationship between postoperative CRP elevation and postoperative major adverse cardiovascular and cerebral events (MACCE) in patients undergoing off-pump coronary artery bypass surgery (OPCAB).

METHODS

The electronic medical records of 1046 patients who underwent OPCAB were reviewed retrospectively. The relationship between postoperative serum CRP and long-term postoperative MACCE (median follow-up 28 months) was investigated.

RESULTS

Patients were divided into quartiles according to maximum postoperative CRP levels (<18, 18-22, 22-27, ≥27 mg dl(-1)). The adjusted hazard ratios (HRs) were 2.15, 2.45, and 2.81, respectively (P=0.004), compared with the lowest quartile (<18 mg dl(-1)). In the multivariate analysis, the postoperative CRP quartile (HR 2.81; P=0.004), postoperative non-use of statins (HR 1.86; P=0.003), and postoperative maximum troponin I (HR 1.02; P<0.001) independently predicted postoperative MACCE, while preoperative CRP did not (P=0.203). Several parameters were correlated with postoperative maximum CRP level: body temperature (P=0.001) and heart rate (P<0.001) at the end of surgery; intraoperative last lactate (P<0.001) and base excess (P<0.001); and red blood cell transfusion (P=0.019).

CONCLUSIONS

Postoperative CRP elevation was associated with long-term postoperative MACCE in OPCAB patients. This was mitigated by postoperative statin medication. Furthermore, postoperative CRP elevation was associated with intraoperative parameters reflecting hypoperfusion and inflammation.

Pulse pressure variation to predict fluid responsiveness in spontaneously breathing patients: tidal vs. forced inspiratory breathing

We evaluated whether pulse pressure variation can predict fluid responsiveness in spontaneously breathing patients. Fifty-nine elective thoracic surgical patients were studied before induction of general anaesthesia. After volume expansion with hydroxyethyl starch 6 ml.kg(-1) , patients were defined as responders by a ≥ 15% increase in the cardiac index. Haemodynamic variables were measured before and after volume expansion and pulse pressure variations were calculated during tidal breathing and during forced inspiratory breathing. Median (IQR [range]) pulse pressure variation during forced inspiratory breathing was significantly higher in responders (n = 29) than in non-responders (n = 30) before volume expansion (18.2 (IQR 14.7-18.2 [9.3-31.3])% vs. 10.1 (IQR 8.3-12.6 [4.8-21.1])%, respectively, p < 0.001). The receiver-operating characteristic curve revealed that pulse pressure variation during forced inspiratory breathing could predict fluid responsiveness (area under the curve 0.910, p < 0.0001). Pulse pressure variation measured during forced inspiratory breathing can be used to guide fluid management in spontaneously breathing patients.

Highly purified mussel adhesive protein to secure biosafety for in vivo applications

BACKGROUND

Unique adhesive and biocompatibility properties of mussel adhesive proteins (MAPs) are known for their great potential in many tissue engineering and biomedical applications. Previously, it was successfully demonstrated that redesigned hybrid type MAP, fp-151, mass-produced in Gram-negative bacterium Escherichia coli, could be utilized as a promising adhesive biomaterial. However, purification of recombinant fp-151 has been unsatisfactory due to its adhesive nature and polarity which make separation of contaminants (especially, lipopolysaccharide, a toxic Gram-negative cell membrane component) very difficult.

RESULTS

In the present work, we devised a high resolution purification approach to secure safety standards of recombinant fp-151 for the successful use in in vivo applications. Undesirable impurities were remarkably eliminated as going through sequential steps including treatment with multivalent ion and chelating agent for cell membrane washing, mechanical cell disruption, non-ionic surfactant treatment for isolated inclusion body washing, acid extraction of washed inclusion body, and ion exchange chromatography purification of acid extracted sample. Through various analyses, such as high performance liquid chromatographic purity assay, limulus amoebocyte lysate endotoxin assay, and in vitro mouse macrophage cell tests on inflammation, viability, cytotoxicity, and apoptosis, we confirmed the biological safety of bacterial-derived purified recombinant fp-151.

CONCLUSIONS

Through this purification design, recombinant fp-151 achieved 99.90% protein purity and 99.91% endotoxin reduction that nearly no inflammation response was observed in in vitro experiments. Thus, the highly purified recombinant MAP would be successfully used as a safety-secured in vivo bioadhesive for tissue engineering and biomedical applications.

Mussel-mimetic protein-based adhesive hydrogel

Hydrogel systems based on cross-linked polymeric materials which could provide both adhesion and cohesion in wet environment have been considered as a promising formulation of tissue adhesives. Inspired by marine mussel adhesion, many researchers have tried to exploit the 3,4-dihydroxyphenylalanine (DOPA) molecule as a cross-linking mediator of synthetic polymer-based hydrogels which is known to be able to achieve cohesive hardening as well as adhesive bonding with diverse surfaces. Beside DOPA residue, composition of other amino acid residues and structure of mussel adhesive proteins (MAPs) have also been considered important elements for mussel adhesion. Herein, we represent a novel protein-based hydrogel system using DOPA-containing recombinant MAP. Gelation can be achieved using both oxdiation-induced DOPA quinone-mediated covalent and Fe(3+)-mediated coordinative noncovalent cross-linking. Fe(3+)-mediated hydrogels show deformable and self-healing viscoelastic behavior in rheological analysis, which is also well-reflected in bulk adhesion strength measurement. Quinone-mediated hydrogel has higher cohesive strength and can provide sufficient gelation time for easier handling. Collectively, our newly developed MAP hydrogel can potentially be used as tissue adhesive and sealant for future applications.

Interfacial tension of complex coacervated mussel adhesive protein according to the Hofmeister series

Complex coacervation is a liquid-liquid phase separation in a colloidal system of two oppositely charged polyelectrolytes or colloids. The interfacial tension of the coacervate phase is the key parameter for micelle formation and interactions with the encapsulating material. However, the relationship between interfacial tensions and various salt solutions is poorly understood in complex coacervation. In the present work, the complex coacervate dynamics of recombinant mussel adhesive protein (MAP) with hyaluronic acid (HA) were determined in the presence of Hofmeister series salt ions. Using measurements of absorbance, hydrodynamic diameter, capillary force, and receding contact angle in the bulk phase, the interfacial tensions of complex coacervated MAP/HA were determined to be 0.236, 0.256, and 0.287 mN/m in 250 mM NaHCOO, NaCl, and NaNO3 solutions, respectively. The sequences of interfacial tensions and contact angles of the complex coacervates in the presence of three sodium salts with different anions were found to follow the Hofmeister ordering. The tendency of interfacial tension between the coacervate and dilute phases in the presence of different types of Hofmeister salt ions could provide a better understanding of Hofmeister effects on complex coacervated materials based on the protein-polysaccharide system. This information can also be utilized for microencapsulation and adsorption by controlling intramolecular interactions. In addition, the injection molding dynamics of mussel byssus formation was potentially explained based on the measured interfacial tension of coacervated MAP.

Abstract P2-02-08: MRI in predicting pathological response of breast cancer after neoadjuvant chemotherapy: Correlation with tumor size and morphology changes

PURPOSE

Contrast enhanced MR imaging is widely used to monitor the response of neoadjuvant chemotherapy (NAC) in breast cancer patients. The objectives of the study are 1) to assess the response of neoadjuvant chemotherapy (NAC) according to molecular biomarker status using MRI, 2) to evaluation of changes in morphological variation, and 3) to compare MR imaging-pathological size discrepancy depending on molecular biomarker status.

MATERIALS AND METHODS

Between May 2007 and March 2012, a total of 47 patients (age range, 34-65 years; mean age, 48 years) underwent NAC prior to surgery. Among them, 34 patients who performed MRI before and after NAC were enrolled. The extent of the lesion is measured by longest diameter. The response to NAC was calculated as reduction rate between pre NAC MRI and post NAC MRI. Histological grading system - Miller and Payne grade - was also recorded. Patients were divided into subgroups based on human epidermal growth factor receptor 2 (HER2), hormone receptors (HRs), and the proliferation marker Ki-67 status. The morphologic changes were classified into 1) concentric reduction, 2) fragmentation, 3) non-mass like, and 4) architectural distortion.

RESULTS

Total of 34 lesions from 34 patients were included. Among them, 12 lesions (35.3%) were pathologically proven to have no residual tumor (Miller and Payne grade 5). The mean MR reduction rate tended to be higher in HER2-positive (62.7%) and triple negative subgroups (61.9%) than HR-positive subgroup (47.7%). The mean MR imaging-pathologic size discrepancy tended to be smaller in triple negative subgroup (0.5cm) than HER2-positive (1.2cm) and HR-positive subgroups (1.4cm). All results showed no statistical significance (P&gt;0.05). Ki-67 expression showed no significant correlations in tumor response (r = 0.17, P = 0.4) and MR imaging-pathologic size discrepancy (r = 0.1, P = 0.6). The majority of morphologic change is concentric reduction (57.6%). MRI is tended to overestimate residual size of the lesion (62.5%)

CONCLUSION

HER2-positive and triple negative subgroups showed relatively better response. Tumors were most likely to response in the manner of concentric reduction. The mean MR imaging-pathologic size discrepancy tended to be smaller in triple negative subgroup. MRI is reliable method in predicting histopathological response to NAC, but is more likely to overestimate the residual size of the lesion.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-02-08.

A novel maneuver to blindly position bronchial blockers

BACKGROUND

The use of a fiberoptic bronchoscope is fundamental to the positioning of bronchial blockers. However, a fiberoptic bronchoscope could be unavailable. We tried to devise a blind method to locate the blocker without help of a fiberoptic bronchoscope.

METHODS

In 56 thoracic surgical patients requiring one-lung ventilation, a Uniblocker® was inserted into the endotracheal tube and advanced until the blocker balloon just protruded from the endotracheal tube tip. With inflation of the balloon, peak inspiratory pressure increased abruptly with disappearance of expiratory tidal volume. The blocker was advanced with its tip directed to one side until peak inspiratory pressure abruptly dropped and expiratory tidal volume re-appeared. Thereafter, the blocker was advanced 3 cm further with the cuff deflated. Using a fiberoptic bronchoscope, the position of the blocker was checked after re-inflation of the cuff. The entire procedure was repeated on the other side.

RESULTS

Acceptable blocker placements were achieved on 48 of 56 (85.7%) right attempts; the right upper bronchus was not blocked in 5 cases and blocker positions were too shallow in 3. Only 33 of 56 (58.9%) left attempts were acceptable in that blockers could not be advanced into the left bronchus in 19 and were positioned too shallow in 4.

CONCLUSION

This novel technique to blindly position bronchial blockers could be almost successful in isolating the right lung. However, isolation of the left lung was frequently unsuccessful in spite of several attempts.

Influence of a modified propofol equilibration rate constant (k(e0)) on the effect-site concentration at loss and recovery of consciousness with the Marsh model

This study compared the predicted effect-site concentration of propofol at loss and recovery of consciousness when using target-controlled infusion devices with the same pharmacokinetic model (Marsh) but a different plasma effect-site equilibration rate constant (ke0 ), the Diprifusor(TM) (ke0 0.26 min(-1) ) and Base Primea™ (ke0 1.21 min(-1) ). We studied 60 female patients undergoing minor gynaecological surgery under general anaesthesia. Although the total dose of propofol and time until loss of consciousness were comparable, the effect-site concentration at loss of consciousness was significantly lower with the Diprifusor than with the Base Primea (1.2 (0.3) μg.ml(-1) vs 4.5 (0.9) μg.ml(-1) , respectively, p < 0.001). The effect-site concentration at recovery of consciousness was significantly higher with the Diprifusor than with the Base Primea (1.8 (0.4) μg.ml(-1) vs 1.5 (0.2) μg.ml(-1) , respectively, p = 0.01). In conclusion, the effect-site concentration of propofol differs depending on the ke0 , despite the use of the same pharmacokinetic model. Therefore, the ke0 should be considered when predicting loss and recovery of consciousness based on the effect-site concentration of propofol.

A randomized, multi-center, open-label, phase II study of once-per-cycle DA-3031, a biosimilar pegylated G-CSF, compared with daily filgrastim in patients receiving TAC chemotherapy for early-stage breast cancer

BACKGROUNDS

A pegylated form of recombinant granulocyte-colony stimulating factor (G-CSF) was developed for prophylactic use in breast cancer. The aim of this study was to evaluate the efficacy and safety of once-per-cycle DA-3031 in patients receiving chemotherapy for breast cancer.

METHODS

A total of 61 patients receiving docetaxel, doxorubicin, and cyclophosphamide (TAC) chemotherapy were randomized in cycle 1 to receive daily injections of filgrastim (100 μg/m(2)) or a single subcutaneous injection of pegylated filgrastim DA-3031 at a dose of either 3.6 mg or 6 mg.

RESULTS

The mean duration of grade 4 neutropenia in cycle 1 was comparable among the treatment groups (2.48, 2.20, and 2.05 days for filgrastim, DA-3031 3.6 mg and 6 mg, respectively; P=0.275). No statistically significant differences were observed in the incidence of febrile neutropenia between the treatment groups (9.5 %, 15.0 %, and 5.0 % for filgrastim, DA-3031 3.6 mg and 6 mg, respectively; P=0.681) in cycle 1. The incidences of adverse events attributable to G-CSF were similar among the treatment groups.

CONCLUSIONS

Fixed doses of 3.6 mg or 6 mg DA-3031 have an efficacy comparable to that of daily injections of filgrastim in ameliorating grade 4 neutropenia in patients receiving TAC chemotherapy.

A comparative study on the bulk adhesive strength of the recombinant mussel adhesive protein fp-3

Mussel adhesive protein (MAP) type 3 (fp-3) is considered one of the key components for mussel adhesion. However, its bulk adhesive strength has not been characterized due to its availability in limited quantities. In the present work, a feasible production (~47 mg l(-1)) of recombinant fp-3 was achieved, and its bulk adhesive strength was measured for the first time; ~0.57 MPa for the unmodified form and ~0.94 and ~2.28 MPa for the 3,4-dihydroxy-L-phenylalanine (DOPA)-modified form, having a 9.6% yield without and with oxidant treatment, respectively. Furthermore, values for the bulk adhesive strength of several DOPA-modified recombinant MAPs were compared. The maximum adhesive strength of DOPA-modified fp-3 after oxidant treatment was stronger than that of type 5 (fp-5), which has a 6.2% modification yield, and was comparable to that of hybrid types fp-131 and fp-151, which have similar yields (~5%). The strong bulk adhesive property of recombinant fp-3 demonstrates its potential use as a promising bioadhesive.

Effects of surface chemical structure on the mechanical properties of Si(1-x)Ge(x) nanowires

The Young's modulus and fracture strength of Si(1-x)Ge(x) nanowires (NWs) as a function of Ge concentration were measured from tensile stress measurements. The Young's modulus of the NWs decreased linearly with increasing Ge content. No evidence was found for a linear relationship between the fracture strength of the NWs and Ge content, which is closely related to the quantity of interstitial Ge atoms contained in the wire. However, by removing some of the interstitial Ge atoms through rapid thermal annealing, a linear relationship could be produced. The discrepancy in the reported strength of Si and Ge NWs between calculated and experimented results could be related to SiO(2-x)/Si interfacial defects that are found in Si(1-x)Ge(x) NWs. It was also possible to significantly decrease the number of interfacial defects in the NWs by incorporating a surface passivated Al2O3 layer, which resulted in a substantial increase in fracture strength.

Coil protection using small helical coils for wide-neck intracranial aneurysms: a novel approach

BACKGROUND AND PURPOSE

A number of remodeling or protective techniques available to treat wide-neck intracranial aneurysms are increasingly being used, provided that the shape/type of aneurysm, vessel diameter, and inherent course of the vessel are conducive to their use. The purpose of this study was to describe a novel method using coil protection for treatment of wide-neck aneurysms.

MATERIALS AND METHODS

This technique involves sequential maneuvers to the aneurysm and affected branch artery. A microcatheter is first introduced into the aneurysmal sac, and another microcatheter is introduced into the entrance of the branch artery, followed by partial deployment of a small helical coil into the branch artery. A framing coil is then placed within the aneurysmal sac, under the protection of the helical coil. After completion of the first coil insertion, the helical coil should be retrieved to confirm the stability of the framing coil. The helical coil can also serve as a filler.

RESULTS

This technique was successfully applied to 12 intracranial saccular aneurysms of the MCA bifurcation (5 patients); anterior communicating artery (3 patients); and A1 and M1 segments, distal ACA, and basilar tip (1 patient each). Selective endovascular treatment was successfully performed and resulted in excellent outcomes in all patients. There were no complications directly related to coil protection.

CONCLUSIONS

Our small study suggests that coil protection can be a safe alternative to traditional remodeling or protective techniques when those techniques have failed or are not possible due to vascular geometry. It is particularly suited for the treatment of wide-neck aneurysms arising from small and acutely angulated branching vessels.

Functional interaction analysis of GM1-related carbohydrates and Vibrio cholerae toxins using carbohydrate microarray

The development of analytical tools is important for understanding the infection mechanisms of pathogenic bacteria or viruses. In the present work, a functional carbohydrate microarray combined with a fluorescence immunoassay was developed to analyze the interactions of Vibrio cholerae toxin (ctx) proteins and GM1-related carbohydrates. Ctx proteins were loaded onto the surface-immobilized GM1 pentasaccharide and six related carbohydrates, and their binding affinities were detected immunologically. The analysis of the ctx-carbohydrate interactions revealed that the intrinsic selectivity of ctx was GM1 pentasaccharide ≫ GM2 tetrasaccharide > asialo GM1 tetrasaccharide ≥ GM3trisaccharide, indicating that a two-finger grip formation and the terminal monosaccharides play important roles in the ctx-GM1 interaction. In addition, whole cholera toxin (ctxAB(5)) had a stricter substrate specificity and a stronger binding affinity than only the cholera toxin B subunit (ctxB). On the basis of the quantitative analysis, the carbohydrate microarray showed the sensitivity of detection of the ctxAB(5)-GM1 interaction with a limit-of-detection (LOD) of 2 ng mL(-1) (23 pM), which is comparable to other reported high sensitivity assay tools. In addition, the carbohydrate microarray successfully detected the actual toxin directly secreted from V. cholerae, without showing cross-reactivity to other bacteria. Collectively, these results demonstrate that the functional carbohydrate microarray is suitable for analyzing toxin protein-carbohydrate interactions and can be applied as a biosensor for toxin detection.