Exploitation of a novel adjuvant for polymyxin B against multidrug-resistant Acinetobacter baumannii.

BACKGROUND: Although polymyxin has been used as a last-resort antibiotic against resistant bacteria, its use is restricted due to nephrotoxicity and neurotoxicity. While the present antibiotic resistance issue compels clinicians to reconsider polymyxin use in severe illness cases, polymyxin-resistant microorganisms exert an effect. OBJECTIVES: To address the issue of antibiotic resistance, the cycle of developing new antibiotics to counteract emerging resistance must be discontinued. Here we tried to develop novel therapies that do not rely on direct antimicrobial activity and thus do not promote antibiotic resistance. METHODS: By a high-throughout screening system based on bacterial respiration, chemical compounds accelerating the antimicrobial effects of polymyxin B were screened. In vitro and in vivo tests were performed to validate adjuvanticity. In addition, membrane depolarization and total transcriptome analysis were used to determine molecular mechanisms. RESULTS: PA108, a newly discovered chemical compound, was used to eradicate polymyxin-resistant A. baumannii and three other species in the presence of polymyxin B at concentrations less than the MIC. Since this molecule lacks self-bactericidal action, we hypothesized that PA108 acts as an antibiotic adjuvant, enhancing the antimicrobial activity of polymyxin B against resistant bacteria. At working concentrations, no toxicity was observed in cell lines or mice, although co-treatment with PA108 and polymyxin B increased survival of infected mouse and decreased bacterial loads in organs. CONCLUSIONS: Boosting antibiotic efficiency through the use of antibiotic adjuvants holds significant promise for tackling the rise in bacterial antibiotic resistance.

Crossing the kingdom border: Human diseases caused by plant pathogens.

Interactions between pathogenic microorganisms and their hosts are varied and complex, encompassing open-field scale interactions to interactions at the molecular level. The capacity of plant pathogenic bacteria and fungi to cause diseases in human and animal systems was, until recently, considered of minor importance. However, recent evidence suggests that animal and human infections caused by plant pathogenic fungi, bacteria and viruses may have critical impacts on human and animal health and safety. This review analyses previous research on plant pathogens as causal factors of animal illness. In addition, a case study involving disruption of type III effector-mediated phagocytosis in a human cell line upon infection with an opportunistic phytopathogen, Pseudomonas syringae pv. tomato, is discussed. Further knowledge regarding the molecular interactions between plant pathogens and human and animal hosts is needed to understand the extent of disease incidence and determine mechanisms for disease prevention.

Soft tissue expander for vertically atrophied alveolar ridges: Prospective, multicenter, randomized controlled trial.

OBJECTIVES: Conventional guided bone regeneration (GBR) limits the amount of bone graft due to limited soft tissue expansion. We hypothesize that the use of tissue expander will successfully augment soft tissue prior to bone graft, allowing for sufficient amount of grafting which will lead to a more stable and effective vertical bone graft. The authors aimed to evaluate effectiveness of the novel self-inflating tissue expander for vertical augmentation in terms of soft tissue expansion, clinical outcomes, and related complications. MATERIAL AND METHODS: A prospective, multicenter, randomized controlled trial was performed on patients requiring vertical augmentation. For experimental group patients, the tissue expander was subperiosteally implanted and followed by a tunneling bone graft without full flap reflection. Control patients underwent conventional vertical GBR. Primary objectives were to evaluate the dimensional changes of soft tissue and radiographic vertical bone gain and retention. As a secondary outcome, clinical complications and thickness changes of expanded overlying tissue were assessed and analyzed. RESULTS: Twenty-three patients in each group were included. During a 4-week expansion, two of the experimental group showed over-expansion and one showed mucosal perforation associated with previous severe scars. The other patients showed uneventful expansion and mean tissue augmentation was 6.88 ± 1.64 mm vertically. Ultrasonographic measurements of overlying gingiva revealed no thinning after tissue expansion (p > .05). Significantly higher vertical bone gain was shown in the experimental group (5.12 ± 1.25 mm) compared with that in the control patients (4.22 ± 1.15 mm; p < .05). After a 6-month retention period, the mean vertical bone measurement of the controls had decreased to 1.90 mm (55.0% reduction), which was a significantly greater decrease than that in the experimental group (mean 3.55 mm, 30.7% reduction; p < .05). CONCLUSION: Our results demonstrated the effectiveness of tissue expanders followed by tunneling bone graft for vertical augmentation; however, studies comparing the two techniques without tissue expanders are needed to elucidate the net effect of tissue expansion.

A reliable and controllable graphene doping method compatible with current CMOS technology and the demonstration of its device applications.

The modulation of charge carrier concentration allows us to tune the Fermi level (E F) of graphene thanks to the low electronic density of states near the E F. The introduced metal oxide thin films as well as the modified transfer process can elaborately maneuver the amounts of charge carrier concentration in graphene. The self-encapsulation provides a solution to overcome the stability issues of metal oxide hole dopants. We have manipulated systematic graphene p-n junction structures for electronic or photonic application-compatible doping methods with current semiconducting process technology. We have demonstrated the anticipated transport properties on the designed heterojunction devices with non-destructive doping methods. This mitigates the device architecture limitation imposed in previously known doping methods. Furthermore, we employed E F-modulated graphene source/drain (S/D) electrodes in a low dimensional transition metal dichalcogenide field effect transistor (TMDFET). We have succeeded in fulfilling n-type, ambipolar, or p-type field effect transistors (FETs) by moving around only the graphene work function. Besides, the graphene/transition metal dichalcogenide (TMD) junction in either both p- and n-type transistor reveals linear voltage dependence with the enhanced contact resistance. We accomplished the complete conversion of p-/n-channel transistors with S/D tunable electrodes. The E F modulation using metal oxide facilitates graphene to access state-of-the-art complimentary-metal-oxide-semiconductor (CMOS) technology.

Traumatic Buccal Fat Pad Herniation in Young Children: A Systematic Review and Case Report.

PURPOSE: Traumatic herniation of a buccal fat pad, predominantly seen in young children, is a rare condition. Because of its rarity and clinical features that resemble tumors, clinicians are faced with challenges at the initial diagnosis. This report describes a case of buccal fat pad herniation with excellent long-term prognosis after surgical relocation and conservative treatment and presents a systematic review of the literature on its management. MATERIALS AND METHODS: Through a PubMed search, 811 articles were initially identified. Case series, case reports, technical notes, case and review reports, and retrospective case series were included. After screening and manual review, the sample was narrowed to 35 reports (41 patients) based on eligibility criteria. Articles were included if the standard criteria for traumatic intraoral herniation of buccal fat pad were met. RESULTS: Patients' ages ranged from 4 months to 12 years, with no specific gender predilection. Management consisted of excision (82.9%), relocation (14.6%), and observation (2.4%). Follow-up ranged from 1 week to 4 months. No reports presented a follow-up longer than 4 months; hence, data on long-term prognosis were not reported. For the present case report, a 19-month-old boy diagnosed with traumatic buccal fat pad herniation was successfully treated with surgical relocation and antibiotic support. Twelve-month follow-up showed no esthetic or functional disturbance or recurrence. CONCLUSION: Traumatic herniation of the buccal fat pad requires special attention at the initial diagnosis. Considering its clinical importance in young children and few studies have reported long-term postresection follow-up, surgical relocation can be regarded as an excellent and more conservative treatment option.

Analysis of the relationship between liver regeneration rate and blood levels.

OBJECTIVES: The aim of this study was to investigate the difference of liver function changes according to the liver regeneration rate after liver transplantation through blood tests. METHODS: Fifty donors, who underwent computed tomography (CT) 3D volumetry, were analyzed before and after liver transplantation. CT 3D volumetry was used as a study method to measure the mean liver regeneration volume and regeneration rate. Then, blood levels were measured including alanine transaminase (ALT), aminotransferase (AST), gamma-glutamyl transpeptidase (GGT) and total bilirubin. RESULTS: The liver regeneration rate rapidly increased from 39.13±4.91% befoone1 month and 90.31±13.09% 16 months after surgery furthermore. Blood levels rapidly increased 7 days after surgery and then decreased 16 months after surgery compared to the state before surgery. CONCLUSION: This study results could be used as a basis for the prognosis of future liver transplantations.

Profiles of adverse childhood experiences (ACEs) and psychosocial adjustment in South Korea: Comparison between probation and non-probation youth.

BACKGROUND: Adverse Childhood Experiences (ACEs) are risk factors affecting adolescent psychosocial adjustment. Youth involved in the juvenile justice system are more likely to have ACEs, but few studies have investigated this topic outside the western context. OBJECTIVE: This study aims to (1) compare latent profiles of ACEs among probation and non-probation youth in South Korea and (2) examine which profiles pose the greatest risk of maladaptive psychosocial adjustment (offline risk-taking, online risk-taking, school adjustment, and happiness). PARTICIPANTS AND SETTING: South Korean data adopting survey questions from the Fourth International Self-Report Delinquency Study was analyzed. Adolescents with complete information on regression covariates were included (non-probation: 1846/probation: 368). METHODS: Latent profile analysis was utilized to identify distinctive patterns of ACEs. Multiple linear regression and logistic regression were performed to predict the maladjustment experiences of each latent subgroup. RESULTS: Four ACE profiles emerged for probation and non-probation samples. Three profiles were common (i.e., emotional/physical abuse, emotional neglect, high maltreatment/domestic violence) and one profile was unique (high maltreatment with family dysfunction for the probation sample; moderate maltreatment for the non-probation sample). In the probation sample, compared to the emotional neglect group, the other three profiles showed poorer adjustment in at least one domain. In the non-probation sample, profiles with high emotional/physical abuse and high maltreatment/family dysfunction had poorer outcomes than the emotional neglect group. CONCLUSIONS: These findings indicate the need for a comprehensive approach toward adolescents and their family environments for preventing delinquency and promoting positive youth adjustment.

Phase of Topological Lattice with Leaky Guided Mode Resonance.

Topological nature in different areas of physics and electronics has often been characterized and controlled through topological invariants depending on the global properties of the material. The validity of bulk-edge correspondence and symmetry-related topological invariants has been extended to non-Hermitian systems. Correspondingly, the value of geometric phases, such as the Pancharatnam-Berry or Zak phases, under the adiabatic quantum deformation process in the presence of non-Hermitian conditions, are now of significant interest. Here, we explicitly calculate the Zak phases of one-dimensional topological nanobeams that sustain guided-mode resonances, which lead to energy leakage to a continuum state. The retrieved Zak phases show as zero for trivial and as π for nontrivial photonic crystals, respectively, which ensures bulk-edge correspondence is still valid for certain non-Hermitian conditions.

Collagen Peptide Exerts an Anti-Obesity Effect by Influencing the Firmicutes/Bacteroidetes Ratio in the Gut.

Alterations in the intestinal microbial flora are known to cause various diseases, and many people routinely consume probiotics or prebiotics to balance intestinal microorganisms and the growth of beneficial bacteria. In this study, we selected a peptide from fish (tilapia) skin that induces significant changes in the intestinal microflora of mice and reduces the Firmicutes/Bacteroidetes ratio, which is linked to obesity. We attempted to verify the anti-obesity effect of selected fish collagen peptides in a high-fat-diet-based obese mouse model. As anticipated, the collagen peptide co-administered with a high-fat diet significantly inhibited the increase in the Firmicutes/Bacteroidetes ratio. It increased specific bacterial taxa, including Clostridium_sensu_stricto_1, Faecalibaculum, Bacteroides, and Streptococcus, known for their anti-obesity effects. Consequently, alterations in the gut microbiota resulted in the activation of metabolic pathways, such as polysaccharide degradation and essential amino acid synthesis, which are associated with obesity inhibition. In addition, collagen peptide also effectively reduced all obesity signs caused by a high-fat diet, such as abdominal fat accumulation, high blood glucose levels, and weight gain. Ingestion of collagen peptides derived from fish skin induced significant changes in the intestinal microflora and is a potential auxiliary therapeutic agent to suppress the onset of obesity.

Highly Efficient Experimental Approach to Evaluate Metal to 2D Semiconductor Interfaces in Vertical Diodes with Asymmetric Metal Contacts.

The energy band alignments and associated material properties at the contacts between metal and two-dimensional (2D) semiconducting transition metal dichalcogenide (SCTMD) films determine the important traits in 2D SCTMD-based electronic and optical device applications. In this work, we realize 2D vertical diodes with asymmetric metal-SCTMD contact areas where currents are dominated by the contact-limited charge flows in the transport regimes of Fowler-Nordheim tunneling and Schottky emission. With straightforward current-voltage characteristics, we can accurately evaluate the interface parameters such as Schottky barrier heights and the vertical effective masses of tunneling charges. In particular, the differing contact areas and resultant current rectifications allow us to address specific Schottky barrier locations with respect to the conduction and valence band edges of 2D semiconducting WSe2, WS2, MoSe2, and MoS2, thereby determining whether p-type holes or n-type electrons become the majority charge carriers in the SCTMD devices. We demonstrate that our experimental and analytical approaches can be utilized as a simple but powerful material metrology to qualitatively and quantitatively evaluate various metal-SCTMD contacts.

Author Correction: Highly pathogenic H5N6 avian influenza virus subtype clade 2.3.4.4 indigenous in South Korea.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Highly pathogenic H5N6 avian influenza virus subtype clade 2.3.4.4 indigenous in South Korea.

The outbreaks of the highly pathogenic avian influenza (HPAI) in 2016-2017 and 2017-2018, caused by novel reassortant clade 2.3.4.4 H5N6 viruses, resulted in the loss of one billion birds in South Korea. Here, we characterized the H5N6 viruses isolated from wild birds in South Korea from December 2017 to August 2019 by next-generation sequencing. The results indicated that clade 2.3.4.4 H5N6 viruses isolated in 2017 and 2019 shared almost identical nucleotide sequences with the HPAI H5N6 viruses from 2016 in South Korea. This repeated detection of evolutionarily identical H5N6 viruses in same region for more than three years may suggest indigenization of the HPAI H5N6 virus in South Korea. Phylogenetic analysis demonstrated that the clade 2.3.4.4 H5N6 viruses isolated in 2017 and 2019 were evolutionarily distinct from those isolated in 2018. Molecular analysis revealed that the H5N6 viruses isolated in 2017 and 2019 had features associated with an increased risk of human infection (e.g. a deletion at position 133 of HA and glutamic acid residue at position 92 of NS1). Overall, these genomic features of HPAI H5N6 viruses highlight the need for continuous monitoring of avian influenza viruses in wild migratory birds as well as in domestic birds.

Impaired osseointegration of dental implants associated with orthognathic surgery: Possible regional acceleratory phenomenon.

BACKGROUND: Regional acceleratory phenomenon (RAP) is demonstrated to decrease regional bone mineral density and accelerate bone turnover. Hypothesizing that RAP can negatively affect the osseointegration of biomaterials, this study aimed to investigate the possible influence of the RAP on dental implant osseointegration. MATERIALS AND METHODS: Orthognathic surgery, one of the major surgeries on oral and maxillofacial region was set as intervention for RAP. Considering that RAP exerts its physiologic effects until 4 months after noxious stimuli, patients were classified according to the time interval between orthognathic surgery and dental implant installation; group I was designated to patients who had implant installation within 4 months from orthognathic surgery. Group II were those with installation after 4-12 months and group III was longer than 12 months. Radiographic and clinical evaluations of dental implants including peri-implant marginal bone changes (MBR), implant stability, cumulative survival rates were analyzed. RESULTS: A total of 54 patients with 106 implants (mean follow-up of 72.6 months) were included in the study. MBR was significantly higher in group I (2.62 ± 0.91 mm) and II (2.25 ± 0.95 mm) compared to that of group III (0.94 ± 0.90 mm) at last follow up (P < 0.05) and this group difference over time was also significant (P < 0.001). Compared to group III, groups I and II exhibited lower ISQ values and higher biological complications including peri-implantitis and peri-implant gingivitis (P < 0.05). Group I showed significantly low-cumulative survival rate (89.2%; implant-level) compared to groups II and III. CONCLUSIONS: In this study, impaired osseointegration of dental implants was demonstrated associated with orthognathic surgery. Micro-environmental changes of hard tissue induced by major surgery on the jaw showed deteriorating effects on integrity of biomaterial osseointegration. Special considerations should be addressed for ideal treatment results and prognosis.

Effects of pH alteration on the pathogenesis of medication-related osteonecrosis of the jaw.

INTRODUCTION: An acidic environment has been recognized to increase catabolic activities and inhibit osteoblastic deposition, and also exhibited in the pathogenesis of various bone diseases. The aim of the study was to investigate the role of systemic and local pH alteration in the pathogenesis of medication-related osteonecrosis of the jaw (MRONJ). MATERIAL AND METHODS: Initially, MRONJ was induced in 54 Sprague-Dawley rats via subcutaneous bisphosphonate injections, once a week for 8 weeks. A week prior to bisphosphonate termination, surgical intervention was performed and rats were divided into 3 groups-alkalotic, acidic and control group, wherein each received NaHCO3, NH4Cl and normal saline, respectively for 8 weeks. Upon sacrifice, blood was sent for arterial blood pH analysis and their mandibles were subjected to histomorphometric and µCT analyses. ONJ was histologically defined as necrotic bone persisting for eight weeks after surgical intervention. RESULTS: Each intervention exemplified its expected outcome wherein each group exhibited a borderline alkalotic (7.43 ±â€¯0.05) and acidic state (7.27 ±â€¯37), respectively (P < 0.05). Acidic group showed a higher occurrence of MRONJ (95%) compared to that of alkalotic group (60%) and control (76.9%). Histomorphometric and microstructural evaluation revealed that acidic group presented deteriorated bone architectures with significantly higher necrotic bone fraction, clusters of empty lacunae, N.Oc/B.Pm and lower B.Ar./T.Ar, BV/TV, Tb.Th (P < 0.05). Alkalotic group showed possible protective effects against ONJ versus acidic group, however these trends were not statistically significant. CONCLUSIONS: An acidic milieu aggravated ONJ development in an animal model. Further investigations are needed to elucidate the exact role of acid-base balance in MRONJ pathogenesis and possible benefits of alkali supplementation for the prevention.

Chemical Vapor-Deposited Vanadium Pentoxide Nanosheets with Highly Stable and Low Switching Voltages for Effective Selector Devices.

Recently, attempts to overcome the physical limits of memory devices have led to the development of promising materials and architectures for next-generation memory technology. The selector device is one of the essential ingredients of high-density stacked memory systems. However, complicated constituent deposition conditions and thermal degradation are problematic, even with effective selector device materials. Herein, we demonstrate the highly stable and low-threshold voltages of vanadium pentoxide (V2O5) nanosheets synthesized by facile chemical vapor deposition, which have not been previously reported on the threshold switching (TS) properties. The electrons occupying trap sites in poly-crystalline V2O5 nanosheet contribute to the perfectly symmetric TS feature at the bias polarity and low-threshold voltages in V2O5, confirmed by high-resolution transmission electron microscopy measurements. Furthermore, we find an additional PdO interlayer in V2O5 nanodevices connected with a Pd/Au electrode after thermal annealing treatment. The PdO interlayer decreases the threshold voltages, and the Ion/ Ioff ratio increases because of the increased trap density of V2O5. These studies provide insights into V2O5 switching characteristics, which can support low power consumption in nonvolatile memory devices.