Local delivery of pamidronate with collagen matrix mitigates buccal bone resorption following immediate implant placement - An experimental in vivo study.

AIMS: The aim of this experimental in vivo pilot study was to evaluate the effect of the local delivery of pamidronate within a collagen membrane on the changes in the buccal soft and hard tissue dimensions at the time of immediate implant placement and whether this effect was influenced by the placement of bone substitutes. METHODS: In six beagle dogs, the distal roots of the third and fourth premolars were extracted, and immediate implants were placed. Treatment groups were randomly allocated to each socket: (i) covering the buccal bone with pamidronate-soaked collagen membrane (BP group), (ii) filling the gap defect with synthetic bone substitute (BS group), (iii) filling the gap defect with synthetic bone substitute and covering the buccal bone with pamidronate soaked collagen membrane (BP/BS group), (iv) no treatment (control group). Intraoral scanning was performed immediately after the surgery and at 20 weeks. Histomorphometric and micro-computed tomography (CT) outcomes were evaluated at 20 weeks. RESULTS: The micro CT analysis demonstrated that the BP group showed no apparent difference in vertical bone level with residual mesial root area, while control group showed significant buccal bone resorption at the implant site. The histomorphometric analysis demonstrated that the vertical bone level of buccal plate was significantly differed between the BP and control group (0.34 ± 0.93 and 1.27 ± 0.56 mm, respectively; p = .041). There was no statistically significant difference in the horizontal ridge width (HRW 1, 2, 3) among the groups. Also, the thickness, height and buccal contours of the soft tissue did not reveal significant changes among the groups. CONCLUSION: The local delivery of pamidronate to the outer surface of the buccal wall at the time of immediate implant placement effectively limits buccal bone resorption. The results from the present investigation should be interpreted with caution, as well as its clinical translatability. Further investigation is needed to understand the pamidronate binding and releasing kinetic, as well as the ideal carrier of this drug for its topical application.

High Expression of Tetraspanin 5 as a Prognostic Marker of Colorectal Cancer.

Cancer is a major disease and the leading cause of death worldwide, with colorectal cancer (CRC) being the third-most common cancer in Korea. The survival rate associated with CRC reduces as the disease stage increases. Therefore, its early detection and treatment can greatly increase patient survival rates. In this study, we identified the tetraspanin 5 (TSPAN5) gene as an important biomarker for predicting the prognosis of patients with CRC. A TMA slide was used for statistical analysis. pN and clinical stage were found to be significant factors according to chi-square analysis, whereas pT, pN, metastasis, clinical stage, and TSPAN5 expression were significant according to Cox regression analysis. In order to prove the usefulness of TSPAN5, which is overexpressed in patients with metastatic CRC, as a biomarker, proliferation, migration, invasion, and tumorigenicity were examined using cell lines inhibited using small interfering RNA. The evaluations confirmed that TSPAN5 suppression, in turn, suppressed proliferation, migration, invasion, and tumorigenesis, which are characteristic of cancer cells. Therefore, the evaluation of TSPAN5 expression may help observe the prognosis of CRC and determine an appropriate treatment method for patients with CRC.

SNPs in microRNA seed region and impact of miR-375 in concurrent regulation of multiple lipid accumulation-related genes.

Bovine intramuscular fat (IMF), commonly referred to as marbling, is regulated by lipid metabolism, which includes adipogenesis, lipogenesis, glycerolipid synthesis, and lipolysis. In recent years, breeding researchers have identified single nucleotide polymorphisms (SNPs) as useful marker-assisted selection tools for improving marbling scores in national breeding programs. These included causal SNPs that induce phenotypic variation. MicroRNAs (miRNAs) are small highly conserved non-coding RNA molecules that bind to multiple non-coding regions. They are involved in post-transcriptional regulation. Multiple miRNAs may regulate a given target. Previously, three SNPs in the GPAM 3' UTR and four miRNAs were identified through in silico assays. The aim of this study is to verify the binding ability of the four miRNAs to the SNPs within the 3'UTR of GPAM, and to identify the regulatory function of miR-375 in the expression of genes related to lipid metabolism in mammalian adipocytes. It was verified that the four miRNAs bind to the GPAM 3'UTR, and identified that the miR-375 sequence is highly conserved. Furthermore, it was founded that miR-375 upregulated the GPAM gene, C/EBPα, PPARγ and lipid metabolism-related genes and promoted lipid droplet accumulation in 3T3-L1 cells. In conclusion, these results suggest that miR-375 is a multifunctional regulator of multiple lipid metabolism-related genes and may aid in obesity research as a biomarker.

Comprehensive treatment protocol for peri-implantitis: an up-to date narrative review of the literature.

This narrative review describes up-to-date treatment options for peri-implantitis and proposes a treatment protocol and flowchart based on the current scientific evidence. Peri-implantitis treatment should be based on the phased treatment protocol for periodontitis, which is a continuous flow of decisions for extraction, nonsurgical and surgical treatments with step-by-step re-evaluation. The protocol's goals are to fulfill the success criteria for peri-implantitis treatment (probing depth of ≤5 mm, and absence of bleeding on probing, suppuration, and progressive bone loss) and to halt disease progression. Fixtures with peri-implantitis can initially be classified as failed or failing. A failed implant needs to be removed. In contrast, nonsurgical and surgical treatments can be applied to a failing implant. Nonsurgical treatment should be the initial treatment for failing implants; however, sole nonsurgical treatment was regarded as inefficient for peri-implantitis. Recent studies have found that the adjunctive use of antibiotics to nonsurgical debridement increased the success of nonsurgical treatment for peri-implantitis. Surgical treatments can be classified into resective, access, and reconstructive surgeries. The technique should be selected according to the patient's bone defect configuration, which relate to regenerative potential. Various combinations of decontamination methods (e.g., mechanical, chemical, and pharmacological approaches) are required to achieve absolute surface decontamination. Clinicians should select an appropriate surface decontamination strategy according to the purpose of surgery. After signs of disease disappear and its progression is halted through active peri-implantitis treatment, it is necessary to enroll patients into maintenance programs. Compliance of patients with the maintenance program reduces the recurrence of peri-implantitis and sustains clinical success after treatment. Maintenance visits should include professional plaque control and hygiene care reinforcement for patients, and their interval should be set according to individual peri-implantitis risk. Clinicians should remind that peri-implantitis treatment is not a single procedure, but rather a continuing cycle of treatment and re-evaluation.

The Relationship between Social Network Service Use Motives and Subjective Well-Being: The Mediating Effect of Online and Offline Social Capital.

OBJECTIVE: The purpose of this study was to examine the mediating effect of social capital on the relationship between Social Media use motives and subjective well-being. METHODS: In the study, online self-reporting surveys were conducted with Social Media users in their 20s, and data from 445 participants were used for structural equation modeling. RESULTS: The main findings of the study were as follows. First, the interpersonal motives for Social Media use had an indirect effect on subjective well-being by mediating offline bonding capital and online bonding capital. In addition, interpersonal motives had an indirect effect on subjective well-being by dual-mediating online and offline bonding capital. Second, the self-expression motive for Social Media use did not directly affect subjective well-being, but it indirectly affected subjective well-being by mediating offline bonding capital. Third, the information-seeking motive for Social Media use did not directly affect subjective well-being, but it indirectly affected subjective well-being by mediating offline bonding capital. CONCLUSION: This study identified a specific mechanism for how motives for using Social Media affect subjective well-being. Furthermore, the results of this study suggest that the effect of Social Media use on subjective well-being may differ depending on the motive for Social Media use.

High expression of LY6E is an independent prognostic factor of colorectal cancer patients.

Colorectal cancer (CRC) is common cancer worldwide, and the 5­year relative survival rate of CRC patients with distant metastasis is as low as 14%. Therefore, identifying markers of CRC is important for the early detection of CRC and applying appropriate treatment strategies. The lymphocyte antigen 6 family (LY6 family) is closely related to the behavior of various cancer types. Among the LY6 family, the lymphocyte antigen 6 complex, locus E (LY6E), which is specifically highly expressed in CRC. Hence, the effects of LY6E on cell function in CRC and its role in CRC recurrence and metastasis were investigated. Reverse transcription­quantitative PCR, western blotting and in vitro functional studies were carried out using four CRC cell lines. Immunohistochemical analysis of 110 CRC tissues was performed to explore the biological functions and expression patterns of LY6E in CRC. LY6E was overexpressed CRC tissues compared with that in adjacent normal tissues. High expression of LY6E in CRC tissues was an independent prognostic factor of worse overall survival (P=0.048). Knockdown of LY6E using small interfering RNA inhibited CRC cell proliferation, migration, invasion, and soft agar colony formation, indicating some of its effects on CRC carcinogenic functions. High expression of LY6E may have oncogenic functions in CRC and be useful as a valuable prognostic marker and potential therapeutic target for CRC.

Expression of Spermine Oxidase Is Associated with Colorectal Carcinogenesis and Prognosis of Patients.

Uncovering tumor markers of colorectal cancer is important for the early detection and prognosis of the patients. Spermine oxidase (SMOX) is upregulated in various cancers. The present study aims to explore the biologic function and expression patterns of SMOX in colorectal cancer (CRC), the third most common type of cancer worldwide. We used quantitative real-time PCR, Western blot, and in vitro functional studies in four CRC cell lines knocked down by SMOX siRNA and immunohistochemistry in 350 cases of CRC tissues. The results showed that SMOX was overexpressed in CRC cell lines and clinical samples. SMOX overexpression in tumor tissues was an independent prognostic factor, worsening overall survival (p = 0.001). The knock-down of SMOX inhibited CRC cell proliferation, invasion, and soft agar colony formation, uncovering its carcinogenic functions. This study indicated that SMOX overexpression could be an important oncogene in CRC and might serve as a valuable prognostic marker and potential therapeutic target for CRC.

Insight into the 6-thiopurine-mediated termination of the invasive motility of tumor cells derived from inflammatory breast cancer.

Our study showed that a combination of 6-thiopurine (6-TP) drugs and a redox agent effectively inhibits the motility of SUM cells derived from human inflammatory breast cancer (IBC) cells and RhoC-overexpressed mammary epithelium cells. This 6-TP-mediated inhibition of cell motility occurs because the treated 6-TPs target and inactivate RhoC. A molecular mechanism for inactivation by the 6-TP-mediated RhoC is proposed by which treated TPs are converted in cells into 6-thioguanosine phosphate (6-TGNP). This 6-TGNP in turn reacts with the Cys(20) side chain of the redox-sensitive GXXXCGK(S/T)C motif of RhoC to produce a 6-TGNP-RhoC disulfide adduct. A redox agent synergistically enhances the formation process of this disulfide. The adduct that is formed impedes RhoC guanine nucleotide exchange, which populates an inactive RhoC. Our results suggest that 6-TGNP can also react with the redox-sensitive GXXXCGK(S/T)C and GXXXXGK(S/T)C motif of RhoA and Rac, respectively, to produce a 6-TGNP-RhoA and 6-TGNP-Rac disulfide adduct. However, given that RhoC has been shown to be overexpressed in ∼90% of IBC lesions, the populated RhoC but not other Rho proteins is likely to be a primary target for 6-TPs and a redox agent to terminate the metastasis of IBC.

3D-Printed Barrier Membrane Using Mixture of Polycaprolactone and Beta-Tricalcium Phosphate for Regeneration of Rabbit Calvarial Defects.

BACKGROUND: Polycarprolactone and beta tricalcium phosphate (PCL/ß-TCP) are resorbable biomaterials that exhibit ideal mechanical properties as well as high affinity for osteogenic cells. AIM: Objective of this study was to evaluate healing and tissue reaction to the PCL/ß-TCP barrier membrane in the rabbit calvaria model for guided bone regeneration. MATERIALS AND METHODS: The PCL/ß-TCP membranes were 3D printed. Three circular defects were created in calvaria of 10 rabbits. The three groups were randomly allocated for each specimen: (i) sham control; (ii) PCL/ß-TCP membrane (PCL group); and (iii) PCL/ß-TCP membrane with synthetic bone graft (PCL-BG group). The animals were euthanized after two (n = 5) and eight weeks (n = 5) for volumetric and histomorphometric analyses. RESULTS: The greatest augmented volume was achieved by the PCL-BG group at both two and eight weeks (p < 0.01). There was a significant increase in new bone after eight weeks in the PCL group (p = 0.04). The PCL/ß-TCP membrane remained intact after eight weeks with slight degradation, and showed good tissue integration. CONCLUSIONS: PCL/ß-TCP membrane exhibited good biocompatibility, slow degradation, and ability to maintain space over eight weeks. The 3D-printed PCL/ß-TCP membrane is a promising biomaterial that could be utilized for reconstruction of critical sized defects.

Diverse patterns of bone regeneration in rabbit calvarial defects depending on the type of collagen membrane.

PURPOSE: Various crosslinking methods have been introduced to increase the longevity of collagen membranes. The aim of this study was to compare and evaluate the degradation and bone regeneration patterns of 3 collagen membranes. METHODS: Four 8-mm-diameter circular bone defects were created in the calvaria of 10 rabbits. In each rabbit, each defect was randomly allocated to 1) the sham control group, 2) the non-crosslinked collagen sponge (NS) group, 3) the chemically crosslinked collagen membrane (CCM) group, or 4) the biphasic calcium phosphate (BCP)-supplemented ultraviolet (UV)-crosslinked collagen membrane (UVM) group. Each defect was covered with the allocated membrane without any graft material. Rabbits were sacrificed at either 2 or 8 weeks post-surgery, and radiographic and histologic analyses were done. RESULTS: New bone formed underneath the membrane in defects in the CCM and UVM groups, with a distinctive new bone formation pattern, while new bone formed from the base of the defect in the NS and control groups. The CCM maintained its shape until 8 weeks, while the UVM and NS were fully degraded at 8 weeks; simultaneously, sustained inflammatory infiltration was found in the margin of the CCM, while it was absent in the UVM. In conclusion, the CCM showed longer longevity than the UVM, but was accompanied by higher levels of inflammation. CONCLUSIONS: Both the CCM and UVM showed distinctive patterns of enhancement in new bone formation in the early phase. UV crosslinking can be a biocompatible alternative to chemical crosslinking.

Anti-Inflammatory Potential of Complex Extracts of Ligularia stenocephala Matsum. & Koidz. and Secale cereale L. Sprout in Chronic Gingivitis: In Vitro Investigation and Randomized Clinical Trial.

Complex extracts of Ligularia stenocephala Matsum. & Koidz. (LSE) and Secale cereale L. sprout (SCSE) (TEES-10®) were prepared. The purposes of the study were to evaluate anti-inflammatory activities of TEES-10® in vitro and to observe resolution of gingivitis in human with oral administration of TEES-10®. The effects of TEES-10® on normal periodontal ligament (PDL) cell viability, lipopolysaccharide (LPS) induced PDL cell viability and the changes of inflammatory mediator expression were evaluated in vitro. In the clinical trial, 150 mg of TEES-10® powder containing capsule was administered twice daily to the test group, while the control group administered placebos in a total 100 participants with gingivitis. Probing depth (PD), bleeding on probing (BOP), clinical attachment loss, gingival index (GI) and plaque index (PI) were measured at baseline and 4 weeks. Administering TEES-10® showed significant increase in PDL cell viability compared to administering LSE or SCSE alone. In addition, treating TEES-10® to LPS induced PDL cell significantly increased PDL cell viability compared to control. TEES-10® suppressed expression of NF-κB, p-ERK, ERK, COX-2, c-Fos and p-STAT and promoted expression of PPARγ in LPS induced PDL cells. In the clinical trial, significant improvement of GI and BOP was observed in the test group at 4 weeks. In addition, the number of patients diagnosed with gingivitis was significantly reduced in the test group at 4 weeks. Salivary MMP-8 and MMP-9 was also significantly decreased compared to placebo group. Within the limitations of this study, the TEES-10® would have an anti-inflammatory potential clinically in the chronic gingivitis patients.

Ras-targeting action of thiopurines in the presence of reactive nitrogen species.

Thiopurine drugs are commonly used in the treatment of certain cancers, autoimmune disorders, organ transplant rejection, and bowel disease. Because long-term treatment with thiopurines for certain diseases is common, the cytotoxic effects associated with chronic exposure to thiopurine drugs are inevitable. The results shown in this study indicate that the oncogenic Ras in model cancer cell lines forms a complex with thioguanine nucleotide that is derived from long-term treatment with thiopurines. This study also showed that the Ras thioguanine nucleotide binary complex is likely to be a direct target of a redox agent, resulting in downregulation of the oncogenic Ras. This study proposes a radical-based molecular mechanism for the path of Ras-targeting thiopurines used in conjunction with redox agents. Given that Ras plays a central role in cellular signaling pathways, any interference with Ras activity by thiopurines and redox agents has the potential for devastating cytotoxic effects.

Simple purification of human antimicrobial peptide dermcidin (MDCD-1L) by intein-mediated expression in E.coli.

Among human antimicrobial peptides (hAMPs), DCD-1L has a broad spectrum of antimicrobial activity over a wide pH range and in high salt concentrations. It offers a promising alternative to conventional antibiotics. The 458-bp-long dermcidin cDNA was amplified by PCR using a human fetal cDNA library as a template. The 147-bp fragment of the MDCD-1L gene encoding an additional methionine residue was subcloned into the pTYB11 vector. Recombinant MDCD-1L was expressed as an intein fusion protein in E. coli, and then purified by affinity chromatography using chitin beads. A small peptide with a molecular mass of about 5 kDa was detected by tricine gel electrophoresis. The recombinant MDCD-1L peptide was purified from the gel and its amino acid sequence was determined by nanoLC-ESI-MS/MS analysis. The initiating amino acid, methionine, remained attached to the N-terminal region of recombinant MDCD-1L. Purified MDCD-1L showed antimicrobial activity against a Micrococcus luteus test strain.

Oral Fluid Biomarkers for Diagnosing Gingivitis in Human: A Cross-Sectional Study.

Diagnoses based on oral fluid biomarkers have been introduced to overcome limitations of periodontal probe-based diagnoses. Diagnostic ability of certain biomarkers for periodontitis have been identified and widely studied, however, such studies targeting gingivitis is scarce. The aims of this study were to determine and compare the efficacies and accuracies of eight biomarkers in diagnosing gingivitis with the aid of receiver operating characteristic (ROC) curves. The probing depth (PD), clinical attachment loss (CAL), bleeding on probing (BOP), gingival index (GI), and plaque index (PI) were examined in 100 participants. Gingival crevicular fluid was collected using paper points, and whole-saliva samples were collected using cotton roll. Samples were analyzed using enzyme-linked immunosorbent assay kits for the different biomarkers. The levels of matrix metalloproteinase (MMP)-8, MMP-9, lactoferrin, cystatin C, myeloperoxidase (MPO), platelet-activating factor, cathepsin B, and pyridinoline cross-linked carboxyterminal telopeptide of type I collagen were analyzed. MPO and MMP-8 levels in saliva were strongly correlated with gingivitis, with Pearson's correlation coefficients of 0.399 and 0.217, respectively. The area under the curve (AUC) was largest for MMP-8, at 0.814, followed by values of 0.793 and 0.777 for MPO and MMP-9, respectively. The clinical parameters of GI and PI showed strong correlations and large AUC values, whereas PD and CAL did not. MMP-8 and MPO were found to be effective for diagnosing gingivitis. Further investigations based on the results of this study may identify clinically useful biomarkers for the accurate and early detection of gingivitis.

Distinctive bone regeneration of calvarial defects using biphasic calcium phosphate supplemented ultraviolet-crosslinked collagen membrane.

PURPOSE: To overcome several drawbacks of chemically-crosslinked collagen membranes, modification processes such as ultraviolet (UV) crosslinking and the addition of biphasic calcium phosphate (BCP) to collagen membranes have been introduced. This study evaluated the efficacy and biocompatibility of BCP-supplemented UV-crosslinked collagen membrane for guided bone regeneration (GBR) in a rabbit calvarial model. METHODS: Four circular bone defects (diameter, 8 mm) were created in the calvarium of 10 rabbits. Each defect was randomly allocated to one of the following groups: 1) the sham control group (spontaneous healing); 2) the M group (defect coverage with a BCP-supplemented UV-crosslinked collagen membrane and no graft material); 3) the BG (defects filled with BCP particles without membrane coverage); and 4) the BG+M group (defects filled with BCP particles and covered with a BCP-supplemented UV-crosslinked collagen membrane in a conventional GBR procedure). At 2 and 8 weeks, rabbits were sacrificed, and experimental defects were investigated histologically and by micro-computed tomography (micro-CT). RESULTS: In both micro-CT and histometric analyses, the BG and BG+M groups at both 2 and 8 weeks showed significantly higher new bone formation than the control group. On micro-CT, the new bone volume of the BG+M group (48.39±5.47 mm3) was larger than that of the BG group (38.71±2.24 mm3, P=0.032) at 8 weeks. Histologically, greater new bone area was observed in the BG+M group than in the BG or M groups. BCP-supplemented UV-crosslinked collagen membrane did not cause an abnormal cellular reaction and was stable until 8 weeks. CONCLUSIONS: Enhanced new bone formation in GBR can be achieved by simultaneously using bone graft material and a BCP-supplemented UV-crosslinked collagen membrane, which showed high biocompatibility and resistance to degradation, making it a biocompatible alternative to chemically-crosslinked collagen membranes.

Clinical and Microbiological Efficacy of Pyrophosphate Containing Toothpaste: A Double-Blinded Placebo-Controlled Randomized Clinical Trial.

(1) Background: Dental calculus works as a niche wherein pathogenic bacteria proliferate in the oral cavity. Previous studies revealed the anticalculus activity of pyrophosphates, however there was no clinical study that evaluated microbiome changes associated with calculus inhibition. Therefore, the aim of this randomized clinical trial was to evaluate the calculus inhibition of pyrophosphate-containing toothpaste and its effect on oral microbiome changes. (2) Methods: Eighty subjects with a calculus index ≥2 on the lingual of the mandibular anterior tooth were randomly allocated to the test group that pyrophosphate-containing toothpaste was given to or the placebo control group. Full mouth debridement and standardized tooth brushing instruction were given before the allocation. Plaque index, gingival index, calculus index, probing depth, and bleeding on probing were measured at the baseline, and at 4, 8 and 12 weeks. Genomic DNA was extracted from the plaque samples collected at the baseline and at 12 weeks, and 16S ribosomal RNA gene amplicon sequencing was applied for microbiome analysis. (3) Results: None of the clinical parameters showed significant differences by visits or groups, except the plaque index of the test group, which reduced significantly between 4 and 12 weeks. A significant difference of microbiome between the baseline and 12 weeks was observed in the test group. Between baseline and 12 weeks, the proportion of Spirochetes decreased in the control group, and the proportions of Proteobacteria, Fusobacteria and Spirochetes in the phylum level and the proportions of Haemophilus, Fusobacterium and Capnocytophaga in the genus level decreased in the test group. In the test group, as plaque index decreased, Streptococcus increased, and Fusobacterium and Haemophilus parainfluenza decreased. (4) Conclusion: The use of pyrophosphate-containing toothpaste effectively inhibited the dysbiosis of the oral microbiome and the proliferation of pathogenic species in periodontal disease. Clinically, plaque formation in the pyrophosphate-containing toothpaste group was effectively decreased, however there was no significant change in calculus deposition.

Development of Korean Academy of Medical Sciences Guideline on the skin and related system: impairment evaluation of disfigurement in skin and appearance.

The purpose of this study is to develop new standards for the disability evaluation with reference to existing laws and other study reports regarding disabilities for the rational evaluation of the diverse kinds of disfigurement in appearance and skin. Three plastic surgery specialists and 3 dermatology specialists developed a new standard for the disability evaluation which is appropriate for circumstances in Korea. Disability rate does not take into account the social occupation, gender or age of the patient, but instead, evaluate the Activity of Daily Living and the social adaptability of the appearance and skin disfigurement regardless of the balance between different disabilities. We tried to include most cutaneous disorders and categorized them into 3 types; congenital (Type 1), acquired (Type 2) as well as any permanent skin impairment sequelae of disease, trauma or treatment process (Type 3). For type 3 disorders, we tried to rate the score according to the size of involved skin lesion. The disability rate is determined by dividing the disability class into 8 steps based on the seriousness of each type of disability.

Recombinant expression of human cathelicidin (hCAP18/LL-37) in Pichia pastoris.

The constitutive expression of human cathelicidin LL-37 antimicrobial peptide was achieved using the methylotrophic yeast, Pichia pastoris. An LL-37 cDNA clone was amplified by PCR using human fetal cDNA library as template. The 111 bp fragment encoding mature LL-37 gene was subcloned into pGAPZ-E, an episomal form of the pGAPZB vector incorporating PARS1. It was then transformed into the P. pastoris X-33 strain for intracellular expression. A small peptide with a molecular mass of about 5 kDa was detected by 17% peptide-PAGE analysis. The recombinant LL-37 peptide was purified from the gel and its amino acid sequence was determined by LC-ESI-MS/MS analysis. The initiating amino acid, methionine, was still attached to the N-terminal region of recombinant LL-37. LL-37 crude extract from P. pastoris showed an antimicrobial activity against Micrococcus luteus as the test strain. The successful expression of human LL-37 indicates that the system may be applicable to the expression of other human defensins without resorting to fusion protein constructions.

Isolation of Abscisic Acid from Korean Acacia Honey with Anti-Helicobacter pylori Activity.

BACKGROUND: Helicobacter pylori (H. pylori) is linked to the development of the majority of peptic ulcers and some types of gastric cancers, and its antibiotic resistance is currently found worldwide. OBJECTIVE: This study is aimed at evaluating the anti-H. pylori activity of Korean acacia honey and isolating the related active components using organic solvents. MATERIAL AND METHODS: The crude acacia honey was extracted with n-hexane, dichloromethane, ethyl acetate (EtOAc), and n-butanol. The EtOAc extract was subjected to octadecyl-silica chromatography. The extracts and fractions were then examined for anti-H. pylori activity using the agar well diffusion method. The antimicrobial activity of abscisic acid against H. pylori was investigated by determining the minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs), and by performing a time-kill assay. RESULTS: Abscisic acid related to the botanical origins of acacia honey from Korea has been analyzed using ultra-performance liquid chromatography. The MICs and MBCs of abscisic acid were 2.7 ± 1.3 and 6.9 ± 1.9 µg/mL, respectively. The bactericidal activity of abscisic acid (at 10.8 µg/mL corresponding to 4 × MIC) killed the organism within 36-72 h. These results suggest that abscisic acid isolated from Korean acacia honey has antibacterial activity against H. pylori. CONCLUSION: Abscisic acid isolated from Korean acacia honey can be therapeutic and may be further exploited as a potential lead candidate for the development of treatments for H. pylori-induced infections. SUMMARY: The crude acacia honey was extracted with n-hexane, dichloromethane, EtOAc, and n-butanolThe EtOAc extract yielded eight fractions and four subfractions were subsequently obtained chromatographicallyAbscisic acid was isolated from one subfractionAll the solvent extracts and fractions showed antibacterial activity against H. pyloriAbscisic acid exhibited antibacterial activity against H. pylori. Abbreviations used: MeOH: Methanol; EtOAc: Ethyl acetate; TSB: Trypticase soy broth; MIC: Minimum inhibitory concentration; MBC: Minimum bactericidal concentration; CFU: Colony-forming units; UPLC: Ultra-performance liquid chromatography; DAD: Diode array detector; UV: Ultraviolet; ODS: Octadecyl-silica; MS: Mass spectrometry; SE: Standard error.