Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 34
Filter
1.
Arch Insect Biochem Physiol ; 116(1): e22117, 2024 May.
Article in English | MEDLINE | ID: mdl-38706214

ABSTRACT

More and more evidence shows that small noncoding RNAs (ncRNAs) play diverse roles in development, stress response and other cellular processes, but functional study of intermediate-size ncRNAs is still rare. Here, the expression profile of 16 intermediate-size ncRNAs in ovary and testis of silkworm Bombyx mori were analyzed. Twelve ncRNAs, including 5 small nucleolar RNAs (snoRNAs) and 7 unclassified ncRNAs, accumulated more in the testis than in the ovary of silkworm, especially Bm-163, Bm-51 and Bm-68. Four ncRNAs (including three orphan snoRNAs and one unclassified ncRNA) had higher expression level in the ovary than in the testis, especially Bm-86. Overexpression of the testis-enriched snoRNA Bm-68 in the female led to the accumulation of male-specific isoform of doublesex (BmdsxM) and increased the expression ratio of BmdsxM: BmdsxF. While overexpression of ovary-enriched snoRNA Bm-86 in the male decreased the expression ratio of BmdsxM: BmdsxF, indicating the roles of the two snoRNAs played in the alternative splicing of Bmdsx of silkworm, which will provide new clues for the functional study of snoRNAs in insects.


Subject(s)
Alternative Splicing , Bombyx , DNA-Binding Proteins , Insect Proteins , RNA, Small Nucleolar , Animals , Female , Male , Bombyx/genetics , Bombyx/metabolism , Insect Proteins/genetics , Insect Proteins/metabolism , Ovary/metabolism , RNA, Small Nucleolar/genetics , RNA, Small Nucleolar/metabolism , Testis/metabolism
2.
J Biomater Appl ; : 8853282241257183, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816339

ABSTRACT

Addressing fracture-related infections (FRI) and impaired bone healing remains a significant challenge in orthopedics and stomatology. Researchers aim to address this issue by utilizing biodegradable biomaterials, such as magnesium/poly lactic acid (Mg/PLA) composites, to offer antibacterial properties during the degradation of biodegradable implants. Existing Mg/PLA composites often lack sufficient Mg content, hindering their ability to achieve the desired antibacterial effect. Additionally, research on the anti-inflammatory effects of these composites during late-stage degradation is limited. To strengthen mechanical properties, bolster antibacterial efficacy, and enhance anti-inflammatory capabilities during degradation, we incorporated elevated Mg content into PLA to yield Mg/PLA composites. These composites underwent in vitro degradation studies, cellular assays, bacterial tests, and simulation of the PLA degradation microenvironment. 20 wt% and 40 wt% Mg/PLA composites displayed significant antibacterial properties, with three composites exhibiting notable anti-inflammatory effects. In contrast, elevated Mg content detrimentally impacted mechanical properties. The findings suggest that Mg/PLA composites hold promise in augmenting antibacterial and anti-inflammatory attributes within polymers, potentially serving as temporary regenerative materials for treating bone tissue defects complicated by infections.

3.
Insects ; 15(4)2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38667404

ABSTRACT

Acetamiprid is a broad-spectrum neonicotinoid insecticide used in agriculture to control aphids. While recent studies have documented resistance to acetamiprid in several aphid species, the underlying mechanisms are still not fully understood. In this study, we analyzed the transcriptome and metatranscriptome of a laboratory strain of the pea aphid, Acyrthosiphon pisum (Harris, 1776), with reduced susceptibility to acetamiprid after nine generations of exposure to identify candidate genes and the microbiome involved in the adaptation process. Sequencing of the transcriptome of both selected (RS) and non-selected (SS) strains allowed the identification of 14,858 genes and 4938 new transcripts. Most of the differentially expressed genes were associated with catalytic activities and metabolic pathways involving carbon and fatty acids. Specifically, alcohol-forming fatty acyl-CoA reductase (FAR) and acyl-CoA synthetase (ACSF2), both involved in the synthesis of epidermal wax layer components, were significantly upregulated in RS, suggesting that adaptation to acetamiprid involves the synthesis of a thicker protective layer. Metatranscriptomic analyses revealed subtle shifts in the microbiome of RS. These results contribute to a deeper understanding of acetamiprid adaptation by the pea aphid and provide new insights for aphid control strategies.

4.
Food Chem ; 438: 137998, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-37995587

ABSTRACT

The 228Ra and 226Ra isotopes of radium are significant contaminants in food, raising public concern because of their radiotoxicity. Several methods are available for determining 228Ra and 226Ra. However, the application of these procedures is not focused on food but only on water and environmental matrices. In this study, a cost-effective method for the simultaneous determination of 226Ra and 228Ra radioactivity in food samples using liquid scintillation counting was developed. The overall efficiencies of 226Ra and 228Ra in the food samples are 69.4-78.4% and 30.1-35.8%, respectively. The minimum detectable activities of 226Ra and 228Ra are 11.3 mBq/g and 33.4 mBq/g, respectively, in our food sample, obtained using a 1.0 g ash sample and 60 min of counting time. The method was validated using IAEA-certified reference materials and compared with data obtained using gamma spectrometry in tea, kelp, and oyster samples.


Subject(s)
Radium , Scintillation Counting , Scintillation Counting/methods , Water , Radium/analysis
5.
Toxicol Appl Pharmacol ; 479: 116707, 2023 11 15.
Article in English | MEDLINE | ID: mdl-37783235

ABSTRACT

Di-(2-ethylhexyl) phthalate (DEHP), which is a widely used phthalate (PAE), has recently received public attention owing to it causing health problems. The aim of this study was to elucidate the aggravating effects of DEHP on psoriasis and skin toxicity. Human keratinocyte (HaCaT) cells were treated with gradient concentrations of DEHP, and mice with imiquimod (IMQ)-induced psoriasiform dermatitis were hypodermically injected with 40 µg/kg/day of DEHP for seven consecutive days. The skin condition was assessed based on the psoriasis area and severity index score, which indicated the deterioration of IMQ-induced psoriasis-like skin lesions after DEHP exposure. To further analyze the effect of DEHP on psoriasis, the proliferation, inflammation, and tight junction (TJ) damage were examined, which correlated with the development and severity of psoriasis. The results showed that DEHP promoted proliferation both in vivo and in vitro, which manifested as epidermal thickening; an increase in cell viability; upregulation of Ki67, CDK2, cyclinD1, and proliferating cell nuclear antigen; and downregulation of p21. An excessive inflammatory response is an important factor that exacerbates psoriasis, and our results showed that DEHP can trigger the release of inflammatory cytokines as well as the infiltration of T cells. TJ disorders were found in mice and cells after DEHP treatment. Additionally, p38 mitogen-activated protein kinase (MAPK) was strongly activated during this process, which may have contributed to skin toxicity caused by DEHP. In conclusion, DEHP treatment promotes proliferation, inflammation, TJ disruption, and p38 MAPK activation in HaCaT cells and psoriasis-like skin lesions.


Subject(s)
Diethylhexyl Phthalate , Psoriasis , Skin Diseases , Mice , Animals , Humans , Diethylhexyl Phthalate/toxicity , Psoriasis/metabolism , Skin Diseases/chemically induced , Imiquimod/toxicity , Inflammation/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Skin
6.
Autism Res ; 16(10): 2035-2048, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37695276

ABSTRACT

The purpose of this study was to determine the effect of the Cz of high-definition 5-channel tDCS (HD-tDCS) on social function in 4-12 years-old children with autism spectrum disorder (ASD). This study was a randomized, double-blind, pseudo-controlled trial in which 45 ASD children were recruited and divided into three groups with sex, age, and rehabilitation treatment as control variables. Each group of 15 children with ASD was randomly administered active HD-tDCS with the Cz as the central anode, active HD-tDCS with the left dorsolateral prefrontal cortex (F3) as the central anode, and sham HD-tDCS with the Cz as the central anode with 14 daily sessions in 3 weeks. The Social Responsiveness Scale Chinese Version (SRS-Chinese Version) was compared 1 week after stimulation with values recorded 1 week prior to stimulation. At the end of treatment, both the anodal Cz and anodal left DLFPC tDCS decreased the measures of SRS-Chinese Version. The total score of SRS-Chinese Version decreased by 13.08%, social cognition decreased by 18.33%, and social communication decreased by 10.79%, which were significantly improved over the Cz central anode active stimulation group, especially in children with young age, and middle and low function. There was no significant change in the total score and subscale score of SRS-Chinese Version over the Cz central anode sham stimulation group. In the F3 central anode active stimulation group, the total score of SRS-Chinese Version decreased by 13%, autistic behavior decreased by 19.39%, and social communication decreased by 14.39%, which were all significantly improved. However, there was no significant difference in effect between the Cz and left DLPFC stimulation conditions. HD-tDCS of the Cz central anode may be an effective treatment for social dysfunction in children with ASD.

7.
Medicine (Baltimore) ; 102(39): e34524, 2023 Sep 29.
Article in English | MEDLINE | ID: mdl-37773795

ABSTRACT

RATIONALE: Androgenic alopecia (AGA) is a prevalent condition with progressive miniaturization of hair follicles. Currently, reliable treatments have remained limited, and complementary medications for AGA are still being investigated. Traditional Chinese medicine formulas have conspicuous advantages in the treatment of AGA with good development prospects. Zimmer aqueous spray (ZAS) is a water spray containing Zimmer herbal extract powder (ZMWP), which consists of Ligustri lucidi Fructus, Ecliptae Herba, Fallopia multiflora (Thunb.) Harald. and Polygonatum sibiricum Delar. ex Redoute, etc. ZMWP is an active ingredient in the prevention of hair loss. Our aim is to provide evidence for the effectiveness of ZAS in the treatment of AGA. PATIENT CONCERNS: A 41-year-old man had suffered from hair loss for 8 years. INTERVENTIONS: The patient with moderate AGA received 3 to 4 mL ZAS daily or every other day for 3 months. OUTCOMES: The hair density obviously increased after 3 months of therapy. The improvement of hair diameter, vellus hair rate, and 1 hair pilosebaceous unit rate were observed with a trichoscopy and quantitatively analyzed. Besides, honeycomb pigment pattern mitigated and arborized red lines. LESSONS: The results suggested that ZMWP might have the capability of improving hair growth and attenuating AGA, which can be a promising alternative treatment of AGA.


Subject(s)
Alopecia , Hair , Male , Humans , Adult , Alopecia/drug therapy , Hair Follicle , Medicine, Chinese Traditional
8.
Cell Regen ; 12(1): 24, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37378693

ABSTRACT

Intestinal cancer is one of the most frequent and lethal types of cancer. Modeling intestinal cancer using organoids has emerged in the last decade. Human intestinal cancer organoids are physiologically relevant in vitro models, which provides an unprecedented opportunity for fundamental and applied research in colorectal cancer. "Human intestinal cancer organoids" is the first set of guidelines on human intestinal organoids in China, jointly drafted and agreed by the experts from the Chinese Society for Cell Biology and its branch society: the Chinese Society for Stem Cell Research. This standard specifies terms and definitions, technical requirements, test methods for human intestinal cancer organoids, which apply to the production and quality control during the process of manufacturing and testing of human intestinal cancer organoids. It was released by the Chinese Society for Cell Biology on 24 September 2022. We hope that the publication of this standard will guide institutional establishment, acceptance and execution of proper practocal protocols, and accelerate the international standardization of human intestinal cancer organoids for clinical development and therapeutic applications.

9.
Small ; 19(42): e2301638, 2023 10.
Article in English | MEDLINE | ID: mdl-37345962

ABSTRACT

Developing composite materials with optimized mechanics, degradation, and bioactivity for bone regeneration has long been a crucial mission. Herein, a multifunctional Mg/Poly-l-lactic acid (Mg/PLLA) composite membrane based on the "materials plain" concept through the accumulative rolling (AR) method is proposed. Results show that at a rolling ratio of 75%, the comprehensive mechanical properties of the membrane in the rolling direction are self-reinforced significantly (elongation at break ≈53.2%, tensile strength ≈104.0 MPa, Young's modulus ≈2.13 GPa). This enhancement is attributed to the directional arrangement and increased crystallization of PLLA molecular chains, as demonstrated by SAXS and DSC results. Furthermore, the AR composite membrane presents a lamellar heterostructure, which not only avoids the accumulation of Mg microparticles (MgMPs) but also regulates the degradation rate. Through the contribution of bioactive MgMPs and their photothermal effect synergistically, the membrane effectively eliminates bacterial infection and accelerates vascularized bone regeneration both in vitro and in vivo. Notably, the membrane exhibits outstanding rat skull bone regeneration performance in only 4 weeks, surpassing most literature reports. In short, this work develops a composite membrane with a "one stone, four birds" effect, opening an efficient avenue toward high-performance orthopedic materials.


Subject(s)
Bone Regeneration , Polyesters , Rats , Animals , Scattering, Small Angle , X-Ray Diffraction , Polyesters/chemistry , Bacteria
10.
J Cosmet Dermatol ; 22(3): 937-944, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36575894

ABSTRACT

BACKGROUND: Age-related changes to the face pertinent anatomy and important aspects of autologous fat grafting have been widely applied in facial rejuvenation. Various types of autologous fat products (Macrofat, Microfat, SEFF, nanofat, and SVF-gel) with different properties and applicabilities have been introduced and available for surgeons. METHODS: Key differences between common techniques for fat processing and infiltration. Develop a plan for patients based on site-specific facial anatomical zones, we suggested a pyramidal multiple-theory (multi-type, multi-method and multi-layer) for facial fat grafting. Based on the complicated mechanism of the face decrepitude in different layers of facial soft tissue, autologous fat products with various particle sizes and components into different layers. RESULTS: Fifty-eight patients underwent this facial fat grafting strategy from June 2020 to Jan 2022. All achieved cosmetic improvements, with higher patients' satisfaction, and minor complications. Our facial fat grafting strategy takes advantage of different fat products and is able to address the physiological tissue changes during aging, more properly and targetedly, than the traditional facial fat grafting. CONCLUSIONS: Fat grafting to the face aids in volume restoration and rejuvenation, thereby addressing soft-tissue atrophy associated with the aging face, acquired conditions, or congenital malformations. The technique described as "lipo-tumescence" has been successfully used in the breast and other regions of the body that have radiation damage and is discussed in this article specifically for the face and neck.


Subject(s)
Rhytidoplasty , Skin Aging , Humans , Adipose Tissue/transplantation , Face , Rhytidoplasty/methods , Aging , Rejuvenation
11.
J Insect Sci ; 22(3)2022 May 01.
Article in English | MEDLINE | ID: mdl-35738260

ABSTRACT

Aphids exhibit wing polyphenism. Winged and wingless aphid morphs are produced by parthenogenesis depending on population density and host plant quality. Recent studies showed that microRNAs in alate and apterous individuals have differential expression and are involved in wing dimorphism of Acyrthosiphon pisum. From which miR-92a-1-p5 can target the mRNA of flight muscle gene flightin in vitro, but what effect they have on wing development of aphid is unclear. Here with the nanocarrier-delivered RNA interference (RNAi) method, flightin gene was knocked down in winged nymphs of A. pisum. Results showed that the majority (63.33%) of adults had malformed wings, the shape of dorsal longitudinal muscle (DLM) was deformed severely, the dorsoventral flight muscle (DVM) became wider and looser in aphids with flightin reduction compared with the negative control. Overexpression of miR-92a-1-p5 caused decreased expression of flightin and malformed wings of aphids, with a mutant ratio of 62.50%. Morphological analysis of flight musculature showed the consistent result as that with flightin knockdown. These results suggest that flightin is essential for flight musculature formation and wing extension in A. pisum, which can be modulated by miR-92a-1-p5.


Subject(s)
Aphids , MicroRNAs , Animals , Aphids/physiology , MicroRNAs/genetics , MicroRNAs/metabolism , Muscles , Pisum sativum/genetics , Wings, Animal/anatomy & histology
12.
Front Surg ; 9: 865379, 2022.
Article in English | MEDLINE | ID: mdl-35574545

ABSTRACT

Objective: We aim to clarify the vascular and nerve anatomy of the breast and combine it with an ultrasound knife to use in transaxillary endoscopic biplane breast augmentation. Methods: This study is a retrospective review of patients undergoing transaxillary endoscopic biplane breast augmentation between October and October 2021. Related variables were collected using a standardized data collection template. The detailed process of the transaxillary endoscopic biplane breast augmentation under anatomy instruction is carefully described in this study, and the postoperative effect was closely observed. Results: Sixty-three female patients underwent transaxillary endoscopic biplane breast augmentation. The average implants volume counted 242.46 ± 31.34 cc, and the average operation time was 155.92 ± 22.34 min. Patients were followed up for a mean of 13.67 months (range, 3-27 months), and most of the patients achieved good postoperative results and no severe complications and were satisfied with both appearance and function. Conclusions: The application of anatomy combined with an ultrasound knife in transaxillary endoscopic biplane breast augmentation is a promising way to achieve good breast shapes with high patient satisfaction and is worthy of clinical promotion and application.

13.
J Affect Disord ; 309: 186-192, 2022 07 15.
Article in English | MEDLINE | ID: mdl-35461820

ABSTRACT

BACKGROUND: Understanding how symptoms of mood disorders vary over time in relation to each other is potentially valuable for diagnosis and predicting episodes of illness. In this paper, we characterize the degree of similarity of time series of different mood disorder symptoms. METHODS: We collected 32,215 mood disorder symptom questionnaires, administered twice-daily over 18 months to (n = 19) subjects with rapidly cycling bipolar disorder and (n = 20) healthy control subjects, using visual analog scales to rate 11 sets of symptom severity ratings plus a control item. We used Dynamic Time Warping to calculate similarity ratings between all within-subject pairs of severity ratings followed by Exploratory Factor Analysis (EFA) to identify latent factors of symptom time series across all subjects. RESULTS: Two latent factors were identified: one with depression and anxiety; and a second, with concentration, energy, irritability, fatigue, appetite, euphoria/elation and overall mood. Restlessness, racing thoughts, and the control item (daily hours of daylight) did not cluster with any of the others. LIMITATIONS: Limited sample size dictated that we pool bipolar and healthy patients and use an iterative EFA procedure. CONCLUSION: This analysis suggests that, in a pooled sample of individuals with bipolar disorder and in healthy controls, severity ratings of overall depression and overall anxiety vary jointly as one dynamic factor, while some but not all other DSM mood symptoms vary jointly along with overall mood rating as a second dynamic factor. Further investigation may determine if these findings can simplify subjective symptom reporting in mood-monitoring studies.


Subject(s)
Affect , Bipolar Disorder , Bipolar Disorder/diagnosis , Humans , Irritable Mood , Mood Disorders/diagnosis , Psychiatric Status Rating Scales , Time Factors
14.
J Am Chem Soc ; 144(4): 1690-1699, 2022 02 02.
Article in English | MEDLINE | ID: mdl-35007085

ABSTRACT

Interest in developing antibacterial polymers as synthetic mimics of host defense peptides (HPDs) has accelerated in recent years to combat antibiotic-resistant bacterial infections. Positively charged moieties are critical in defining the antibacterial activity and eukaryotic toxicity of HDP mimics. Most examples have utilized primary amines or guanidines as the source of positively charged moieties, inspired by the lysine and arginine residues in HDPs. Here, we explore the impact of amine group variation (primary, secondary, or tertiary amine) on the antibacterial performance of HDP-mimicking ß-peptide polymers. Our studies show that a secondary ammonium is superior to either a primary ammonium or a tertiary ammonium as the cationic moiety in antibacterial ß-peptide polymers. The optimal polymer, a homopolymer bearing secondary amino groups, displays potent antibacterial activity and the highest selectivity (low hemolysis and cytotoxicity). The optimal polymer displays potent activity against antibiotic-resistant bacteria and high therapeutic efficacy in treating MRSA-induced wound infections and keratitis as well as low acute dermal toxicity and low corneal epithelial cytotoxicity. This work suggests that secondary amines may be broadly useful in the design of antibacterial polymers.


Subject(s)
Amines/chemistry , Anti-Bacterial Agents/therapeutic use , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Peptides/therapeutic use , Staphylococcal Infections/drug therapy , Wound Infection/drug therapy , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/chemistry , Escherichia coli/drug effects , Hemolysis/drug effects , Keratitis/drug therapy , Keratitis/microbiology , Keratitis/pathology , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Mice , Microbial Sensitivity Tests , Peptides/chemistry , Peptides/pharmacology , Polymers/chemistry , Staphylococcal Infections/microbiology , Wound Infection/microbiology
15.
Future Oncol ; 17(36): 5177-5187, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34730405

ABSTRACT

Background: Capsular contracture is common in breast augmentation and reconstruction surgery. The present systematic review discusses the safety of textured and smooth implants in the submuscular position. Methods: A literature search was conducted on PubMed and EMBASE from inception until June 2020. The primary outcome was reduction of capsular contracture (Baker grade); others included time of capsular contracture onset, implant position/rupture rate/surface, hematoma/seroma risk, surgeon assessment and patient satisfaction. A total of 7731 patients were included from six publications. Results: The overall risk rate for capsular contracture increased from 7.6 to 25% in 10 years. The capsular contracture rates in textured and smooth implants were 3-14% and 6-20%, respectively, and no significant difference between implants was observed when the implants were placed submuscularly. Submuscular placement and textured implants also reduced the incidence of other complications. Conclusion: This systematic review suggests that appropriate placement reduces capsular contracture rate, irrespective of implant surface.


Lay abstract Breast reconstruction using breast implants is accompanied by complications that occur following surgery and which can lead to repeated surgeries and, ultimately, patient dissatisfaction. A search of published research was conducted on two major databases, and research published before June 2020 was included in our analysis. The primary outcome was the reduction of capsular contracture, a particular postoperative complication. Six articles (including one randomized controlled trial) were identified, with a total of 7731 patients. The overall risk for developing capsular contracture in breast reconstruction and augmentation patients increased from 7.6 to 25% over a period of 10 years. This systematic review suggests that with appropriate placement of the implant, the rate of capsular contracture and other complications can be reduced in women undergoing surgery, irrespective of implant surface type.


Subject(s)
Breast Implants , Implant Capsular Contracture/prevention & control , Mammaplasty/methods , Breast Implantation/adverse effects , Breast Implantation/methods , Breast Implants/adverse effects , Breast Implants/classification , Female , Humans , Implant Capsular Contracture/epidemiology , Implant Capsular Contracture/etiology , Incidence , Mammaplasty/adverse effects , Patient Satisfaction , Surgeons
16.
Nat Commun ; 12(1): 5898, 2021 10 08.
Article in English | MEDLINE | ID: mdl-34625571

ABSTRACT

Methicillin-Resistant Staphylococcus aureus (MRSA) induced infection calls for antibacterial agents that are not prone to antimicrobial resistance. We prepare protease-resistant peptoid polymers with variable C-terminal functional groups using a ring-opening polymerization of N-substituted N-carboxyanhydrides (NNCA), which can provide peptoid polymers easily from the one-pot synthesis. We study the optimal polymer that displays effective activity against MRSA planktonic and persister cells, effective eradication of highly antibiotic-resistant MRSA biofilms, and potent anti-infectious performance in vivo using the wound infection model, the mouse keratitis model, and the mouse peritonitis model. Peptoid polymers show insusceptibility to antimicrobial resistance, which is a prominent merit of these antimicrobial agents. The low cost, convenient synthesis and structure diversity of peptoid polymers, the superior antimicrobial performance and therapeutic potential in treating MRSA infection altogether imply great potential of peptoid polymers as promising antibacterial agents in treating MRSA infection and alleviating antibiotic resistance.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Peptoids/pharmacology , Polymers/pharmacology , Animals , Biofilms/drug effects , Biopolymers/chemistry , Biopolymers/pharmacology , Gram-Positive Bacteria/drug effects , Mice , Microbial Sensitivity Tests , Peptoids/chemistry , Polymerization , Polymers/chemistry , Staphylococcal Infections/drug therapy
17.
Bioact Mater ; 6(12): 4531-4541, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34027238

ABSTRACT

It is an urgent need to tackle drug-resistance microbial infections that are associated with implantable biomedical devices. Host defense peptide-mimicking polymers have been actively explored in recent years to fight against drug-resistant microbes. Our recent report on lithium hexamethyldisilazide-initiated superfast polymerization on amino acid N-carboxyanhydrides enables the quick synthesis of host defense peptide-mimicking peptide polymers. Here we reported a facile and cost-effective thermoplastic polyurethane (TPU) surface modification of peptide polymer (DLL: BLG = 90 : 10) using plasma surface activation and substitution reaction between thiol and bromide groups. The peptide polymer-modified TPU surfaces exhibited board-spectrum antibacterial property as well as effective contact-killing ability in vitro. Furthermore, the peptide polymer-modified TPU surfaces showed excellent biocompatibility, displaying no hemolysis and cytotoxicity. In vivo study using methicillin-resistant Staphylococcus aureus (MRSA) for subcutaneous implantation infectious model showed that peptide polymer-modified TPU surfaces revealed obvious suppression of infection and great histocompatibility, compared to bare TPU surfaces. We further explored the antimicrobial mechanism of the peptide polymer-modified TPU surfaces, which revealed a surface contact-killing mechanism by disrupting the bacterial membrane. These results demonstrated great potential of the peptide-modified TPU surfaces for practical application to combat bacterial infections that are associated with implantable materials and devices.

18.
Article in English | MEDLINE | ID: mdl-33809483

ABSTRACT

In this study, the activity concentrations levels of 210Pb and 210Po in the edible portions of eight seafood samples collected from the Fujian coast of China were determined. The activity concentrations ranged from 0.74 ± 0.08 to 12.6 ± 1.0 Bq/kg for 210Po and from the minimum detectable limit (MDL, 0.80 Bq/kg) to 11. 7 ± 1.1 Bq/kg for 210Pb. The 210Po activity concentration in all the fish organs ranged from 0.68 to 204 Bq/kg (w.w.), and the 210Po activity was mainly concentrated in the stomach, spleen, heart, liver, gonad, and intestine samples. The 210Pb activity concentration in all the fish organs ranged from the MDL to 15.2 Bq/kg (w.w.), and the 210Pb activity was concentrated in the head, fish scale, and gill samples. The annual effective ingestion doses ranged from 82.8 to 255 µSv/a for all age groups, and the lifetime risk of cancers were estimated. Both the effective ingestion doses and cancer risk to humans were within the acceptable ranges.


Subject(s)
Polonium , Radiation Monitoring , Water Pollutants, Radioactive , Animals , China , Humans , Lead , Lead Radioisotopes/analysis , Polonium/analysis , Seafood/analysis , Water Pollutants, Radioactive/analysis
19.
ACS Appl Bio Mater ; 4(5): 3811-3829, 2021 05 17.
Article in English | MEDLINE | ID: mdl-35006811

ABSTRACT

Infections have accounted for the majority of failures in implants over the past decades. Host defense peptide mimicking polymers have been considered as one of the promising antimicrobial candidates for their cost-effective synthesis, broad-spectrum antimicrobial activity, low propensity to induce drug resistance, and remarkable biocompatibility. In this review, covalent-grafting strategies are mainly discussed to tether host defense peptide mimicking polymers on surfaces, aiming to obtain potent antimicrobial activity. In addition to the antimicrobial function, we review the antimicrobial mechanism of these polymer-modified antimicrobial surfaces in precedent literatures. We also review the in vivo subcutaneous implant infection models that are critical assessments for potential biomedical applications. In the end, we provide our perspective on the future development of this field, especially for biomedical applications.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/pharmacology , Biocompatible Materials/pharmacology , Polymers/pharmacology , Prostheses and Implants/microbiology , Prosthesis-Related Infections/drug therapy , Anti-Bacterial Agents/chemistry , Antimicrobial Cationic Peptides/chemistry , Bacteria/drug effects , Biocompatible Materials/chemistry , Humans , Materials Testing , Microbial Sensitivity Tests , Particle Size , Polymers/chemistry , Prosthesis-Related Infections/microbiology , Surface Properties
20.
J Med Chem ; 63(21): 12921-12928, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33126797

ABSTRACT

Therapeutic options to treat multidrug resistant bacteria, especially when present in biofilms, are limited due to their high levels of antibiotic resistance. Here, we report the anti-biofilm and immunomodulatory activities of the host defense peptide (HDP)-mimicking ß-peptide polymer (20:80 Bu:DM) and investigated its activity in vivo. The polymer outperformed antibiotics in the removal and reduction of the viability of established biofilms, achieving a maximum activity of around 80% reduction in viability. Interestingly the polymer also exhibited HDP-like immunomodulation in inducing chemokines and anti-inflammatory cytokines and suppressing lipopolysaccharide-induced proinflammatory cytokines. When tested in a murine, high-density skin infection model using P. aeruginosa LESB58, the polymer was effective in diminishing abscess size and reducing bacterial load. This study demonstrates the dual functionality of HDP-mimicking ß-peptide polymers in inhibiting biofilms and modulating innate immunity, as well as reducing tissue dermonecrosis.


Subject(s)
Anti-Infective Agents/pharmacology , Antimicrobial Cationic Peptides/chemistry , Biofilms/drug effects , Polymers/chemistry , Animals , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/therapeutic use , Cell Survival/drug effects , Cytokines/pharmacology , Disease Models, Animal , Humans , Immunity, Innate/drug effects , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Peptidomimetics , Polymers/pharmacology , Polymers/therapeutic use , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Skin Diseases/drug therapy , Skin Diseases/microbiology , Skin Diseases/pathology
SELECTION OF CITATIONS
SEARCH DETAIL