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1.
Appl Environ Microbiol ; 90(4): e0126023, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38501925

ABSTRACT

The hydrophobic layer of Aspergillus conidia, composed of RodA, plays a crucial role in conidia transfer and immune evasion. It self-assembles into hydrophobic rodlets through intramolecular disulfide bonds. However, the secretory process of RodA and its regulatory elements remain unknown. Since protein disulfide isomerase (PDI) is essential for the secretion of many disulfide-bonded proteins, we investigated whether PDI is also involved in RodA secretion and assembly. By gene knockout and phenotypic analysis, we found that Pdi1, one of the four PDI-related proteins of Aspergillus fumigatus, determines the hydrophobicity and integrity of the rodlet layer of the conidia. Preservation of the thioredoxin-active domain of Pdi1 was sufficient to maintain conidial hydrophobicity, suggesting that Pdi1 mediates RodA assembly through its disulfide isomerase activity. In the absence of Pdi1, the disulfide mismatch of RodA in conidia may prevent its delivery from the inner to the outer layer of the cell wall for rodlet assembly. This was demonstrated using a strain expressing a key cysteine-mutated RodA. The dormant conidia of the Pdi1-deficient strain (Δpdi) elicited an immune response, suggesting that the defective conidia surface in the absence of Pdi1 exposes internal immunogenic sources. In conclusion, Pdi1 ensures the correct folding of RodA in the inner layer of conidia, facilitating its secretion into the outer layer of the cell wall and allowing self-assembly of the hydrophobic layer. This study has identified a regulatory element for conidia rodlet assembly.IMPORTANCEAspergillus fumigatus is the major cause of invasive aspergillosis, which is mainly transmitted by the inhalation of conidia. The spread of conidia is largely dependent on their hydrophobicity, which is primarily attributed to the self-assembly of the hydrophobic protein RodA on the cell wall. However, the mechanisms underlying RodA secretion and transport to the outermost layer of the cell wall are still unclear. Our study identified a critical role for Pdi1, a fungal protein disulfide isomerase found in regulating RodA secretion and assembly. Inhibition of Pdi1 prevents the formation of correct S-S bonds in the inner RodA, creating a barrier to RodA delivery and resulting in a defective hydrophobic layer. Our findings provided insight into the formation of the conidial hydrophobic layer and suggested potential drug targets to inhibit A. fumigatus infections by limiting conidial dispersal and altering their immune inertia.


Subject(s)
Aspergillosis , Aspergillus fumigatus , Aspergillus fumigatus/genetics , Protein Disulfide-Isomerases/genetics , Protein Disulfide-Isomerases/metabolism , Fungal Proteins/metabolism , Spores, Fungal/genetics , Aspergillosis/metabolism , Hydrophobic and Hydrophilic Interactions , Disulfides/metabolism
2.
Antioxidants (Basel) ; 12(7)2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37507873

ABSTRACT

Both catalase and peroxiredoxin show high activities of H2O2 decomposition and coexist in the same organism; however, their division of labor in defense against H2O2 is unclear. We focused on the major peroxiredoxin (PrxA) and catalase (CatB) in Aspergillus nidulans at different growth stages to discriminate their antioxidant roles. The dormant conidia lacking PrxA showed sensitivity to high concentrations of H2O2 (>100 mM), revealing that PrxA is one of the important antioxidants in dormant conidia. Once the conidia began to swell and germinate, or further develop to young hyphae (9 h to old age), PrxA-deficient cells (ΔprxA) did not survive on plates containing H2O2 concentrations higher than 1 mM, indicating that PrxA is an indispensable antioxidant in the early growth stage. During these early growth stages, absence of CatB did not affect fungal resistance to either high (>1 mM) or low (<1 mM) concentrations of H2O2. In the mature hyphae stage (24 h to old age), however, CatB fulfills the major antioxidant function, especially against high doses of H2O2. PrxA is constitutively expressed throughout the lifespan, whereas CatB levels are low in the early growth stage of the cells developing from swelling conidia to early growth hyphae, providing a molecular basis for their different contributions to H2O2 resistance in different growth stages. Further enzyme activity and cellular localization analysis indicated that CatB needs to be secreted to be functionalized, and this process is confined to the growth stage of mature hyphae. Our results revealed differences in effectiveness and timelines of two primary anti-H2O2 enzymes in fungus.

3.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(3): 293-299, 2021 Jun 01.
Article in English, Chinese | MEDLINE | ID: mdl-34041878

ABSTRACT

OBJECTIVES: This study aimed to evaluate the application value of a modified retroauricular hairline incision and a sternocleidomastoid flap with an inferior pedicle in the resection of benign parotid gland tumors. METHODS: Forty-eight patients with benign parotid gland tumors were retrospectively analyzed: 19 cases were included in the experimental group with an improved retroauricular hairline incision and a sternocleidomastoid flap with an inferior pedicle, and 29 cases were assigned in the control group with a modified facelift incision. Operation time, postoperative drainage, postoperative esthetic degree, and incidence of facial nerve paralysis, salivary fistula, and Frey's syndrome were compared. RESULTS: After the esthetic procedure, the average score of the experimental group was higher than that of the control group, and the esthetic effect of the former was better than that of the latter (P<0.05). The incidence of the operation time, facial nerve paralysis, salivary fistula, and Frey's syndrome of both groups had no statistically significant differences (P>0.05). CONCLUSIONS: The modified retroauricular hairline incision and sternocleidomastoid flap with an inferior pedicle can be applied to resect benign parotid gland tumors safely. It shows a better cosmetic effect and does not cause obvious postoperative complications. Therefore, it should be promoted for tumor treatments.


Subject(s)
Parotid Neoplasms , Sweating, Gustatory , Esthetics, Dental , Humans , Parotid Gland/surgery , Parotid Neoplasms/surgery , Postoperative Complications , Retrospective Studies
4.
Biomed Pharmacother ; 125: 109869, 2020 May.
Article in English | MEDLINE | ID: mdl-32007916

ABSTRACT

Ixeris sonchifolia (IS), principally its dried form, is widely used as traditional and folk medicines in some Asian countries, especially China. In this review, we summarized its traditional uses, chemical constituents, quality control measures, pharmacological activities, therapeutic evaluation, toxicity evaluation and clinical applications. 130 chemical constituents isolated from IS have been reported, including flavones, sesquiterpenes, triterpenes, phenylpropanoids, organic acids and others. They showed various pharmacological activities, such as protecting cardiocerebral vascular system, anticancer effect and antiviral etc. The quality control evaluation studies, clinical applications, other possible applications and suggestions for future research also were discussed. The aim of this review is to critically appraise the available literature and suggest directions for further development of IS to improve its medical value and use.


Subject(s)
Asteraceae/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Animals , Clinical Studies as Topic , Drug Evaluation, Preclinical , Humans , Medicine, Traditional/methods , Medicine, Traditional/standards , Molecular Structure , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Phytochemicals/therapeutic use , Plant Extracts/isolation & purification , Plant Extracts/therapeutic use , Structure-Activity Relationship
5.
Biomed Pharmacother ; 121: 109589, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31810130

ABSTRACT

Salvia plebeia R. Br. (SP), has been widely used in traditional Chinese medicine (TCM). It contains a number of chemical components and reported to possess a variety of pharmacological activities. SP is distributed in many countries such as China, Korea, Japan, Afghanistan and India. SP was first described in Compendium of Materia Medica in the Ming dynasty. The aim of this review is to compile all the information reported in the literature on SP. This review covers traditional uses, including 16 TCM classics and 21 traditional prescriptions; a total of 93 compounds from SP have been reported, including flavonoids, monoterpenoids, sesquiterpenoids, diterpenoids, triterpenes, phenolic acids etc; biological actives such as antioxidant, antimicrobial, hypoglycaemic, anti-inflammatory, analgesic, sedative, antiasthmatic, antiviral, antitumour, hepatoprotective effects etc. In addition, this paper also compiled the quality control studies and clinical applications. The future prospects and the existing problems of SP were also discussed. Overall, we believe this review will be a comprehensive record of SP for researchers to refer for carrying out for further research.


Subject(s)
Phytochemicals/analysis , Phytochemicals/pharmacology , Salvia/chemistry , Animals , Humans , Medicine, Chinese Traditional , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Precision Medicine , Quality Control , Reference Standards
6.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-831385

ABSTRACT

Objective @#To assess the safety and feasibility of incision in the retroauricular sulcus for removal of benign tumors in the lower pole of the parotid gland and to provide some ideas for aesthetic consideration of parotidectomy.@*Methods@# In total, 18 cases with benign tumors of the lower pole regions of the parotid gland were included in this study, including 9 pleomorphic adenomas, 2 myoepitheliomas, 5 Warthin tumors, 1 basal cell adenoma and 1 oncocytoma. Three months after the operation, facial paralysis and salivary fistula were assessed. A visual analog scale was used to score the cosmetic satisfaction of the surgical incision. Tumor recurrence was followed up 6 ~ 12 months after operation.@*Results@# In 18 patients with benign tumors the lower pole regions of the parotid gland, the tumor diameter ranges from 1.0 to 3.1 cm, with an average value of 2.5 cm. All patients experienced successful complete removal of the parotid mass with the minimally invasive retroauricular approach, and all wounds healed in one stage after operation. No serious complications, such as permanent facial paralysis and tumor recurrence, occurred 3 months after the operation. The patients were satisfied with the appearance of the surgical incision (aesthetic score 9.3 ± 0.4), achieving the expected aesthetic effect. @*Conclusion@#This approach is feasible and safe for most small benign parotid tumors located in the lower pole region of the parotid gland and in the posterior region of the jaw. The scar is located in the retroauricular sulcus, which significantly meets the aesthetic needs of the concealed incision for patients.

7.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(6): 677-680, 2019 Dec 01.
Article in Chinese | MEDLINE | ID: mdl-31875450

ABSTRACT

Cleidocranial dysplasia is a rare autosomal dominant hereditary disease characterized by abnormal skeletal and dental development. In this work, a case of cleidocranial dysplasia is reported, and a new frameshift mutation is confirmed by gene detection.


Subject(s)
Cleidocranial Dysplasia , Core Binding Factor Alpha 1 Subunit , Diagnostic Tests, Routine , Humans , Mutation
8.
Nitric Oxide ; 78: 11-21, 2018 08 01.
Article in English | MEDLINE | ID: mdl-29777774

ABSTRACT

AIMS: Ischemic stroke is one of the leading causes of death worldwide. MicroRNAs (miRNAs) have been reported to be implicated in cerebral hypoxia injury and could serve as a therapeutic target. As the third gasotransmitter, hydrogen sulfide (H2S) plays a critical role in hypoxia-induced injury in the central nervous system. Cystathionine ß-synthase (CBS) is the main enzyme catalyzing the production of H2S in brain. The objective of this study was to investigate the effect of miR-125b-5p on protecting against oxygen and glucose deprivation (OGD) injury in PC-12 cells by regulating CBS and H2S generation. RESULTS: The level of miR-125b-5p was increased in the rat MCAO model as well as OGD model in PC-12 cells. Meanwhile, CBS expression was remarkably downregulated. Overexpression of miR-125b-5p reduced CBS expression, decreased the H2S generation, and deteriorated OGD injury in PC-12 cells. On the contrary, silencing miR-125b-5p protected PC-12 cells from OGD injury by upregulated CBS and H2S levels. We found the protective effect of miR-125b-5p inhibition was associated with anti-oxidative and anti-apoptotic cell signaling through decreasing ROS level and reducing mitochondrial membrane potential (ΔΨm). Furthermore, the protective effect was absent when CBS was knockdown in PC-12 cells. INNOVATION AND CONCLUSION: Our research discovered the regulation of CBS by miR-125b-5p. Besides, we provide the evidence for the therapeutic potential of miR-125b-5p inhibition for cerebral ischemia via CBS/H2S pathway.


Subject(s)
Cystathionine beta-Synthase/metabolism , Hydrogen Sulfide/metabolism , Infarction, Middle Cerebral Artery/physiopathology , MicroRNAs/metabolism , Animals , Apoptosis/physiology , Cell Hypoxia/physiology , Gene Knockdown Techniques , Male , Membrane Potential, Mitochondrial/physiology , MicroRNAs/antagonists & inhibitors , MicroRNAs/genetics , MicroRNAs/pharmacology , Oxidative Stress/physiology , PC12 Cells , Protective Agents/pharmacology , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Up-Regulation
9.
J Biomed Mater Res B Appl Biomater ; 106(5): 2029-2036, 2018 07.
Article in English | MEDLINE | ID: mdl-29076251

ABSTRACT

While Ag nanoparticles hold great promise for broad spectrum antibacterial activity, the potential risks of Ag nanoparticles (NPs) on human health remain a challenge. In this study, Ag/Fe3 O4 composites have been successfully prepared and characterized by transmission electron microscopy, X-ray powder diffraction, and Fourier-transform infrared spectroscopy, and their magnetic and antibacterial properties have been assessed. In vivo results show that the antibacterial effect of 500 µg/mL Ag/Fe3 O4 nanocomposites was significantly higher than that of 1000 µg/mL AgNPs after 72 h of treatment (p < 0.01). Hematoxylin and eosin (HE) staining showed that squamous epithelium and dermis collagen fibers formed in the Ag/Fe3 O4 group after 8 days treatment. Wound closure was significantly better for the Ag/Fe3 O4 group than for the AgNPs group. On the other hand, there was less Ag in blood, liver, and kidney in the Ag/Fe3 O4 group, as more Ag was retained in the wound. According to lactate dehydrogenase, γ-glutamyl transpeptidase, and reactive oxygen species results, Ag/Fe3 O4 nanocomposites caused less unwanted side-effects. This work presents a new paradigm to reduce the unwanted side-effects of AgNPs and improve their antibacterial activity, providing a new avenue for wound healing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2029-2036, 2018.


Subject(s)
Anti-Bacterial Agents , Ferrosoferric Oxide , Nanocomposites/chemistry , Reactive Oxygen Species/metabolism , Silver , Wound Infection/drug therapy , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Ferrosoferric Oxide/chemistry , Ferrosoferric Oxide/pharmacology , Male , Microscopy, Electron, Transmission , Molybdoferredoxin , Nanocomposites/adverse effects , Nanocomposites/ultrastructure , Rats , Rats, Sprague-Dawley , Silver/chemistry , Silver/pharmacology , Wound Healing/drug effects , Wound Infection/pathology , X-Ray Diffraction
10.
Nanoscale ; 8(18): 9815-21, 2016 May 05.
Article in English | MEDLINE | ID: mdl-27119975

ABSTRACT

Gold nanoclusters (Au NCs) as ultrasmall fluorescent nanomaterials possess discrete electronic energy and unique physicochemical properties, but suffer from relatively low quantum yield (QY) which severely affects their application in displays and imaging. To solve this conundrum and obtain highly-efficient fluorescent emission, 2D exfoliated layered double hydroxide (ELDH) nanosheets were employed to localize Au NCs with a density as high as 5.44 × 10(13) cm(-2), by virtue of the surface confinement effect of ELDH. Both experimental studies and computational simulations testify that the excited electrons of Au NCs are strongly confined by MgAl-ELDH nanosheets, which results in a largely promoted QY as well as prolonged fluorescence lifetime (both ∼7 times enhancement). In addition, the as-fabricated Au NC/ELDH hybrid material exhibits excellent imaging properties with good stability and biocompatibility in the intracellular environment. Therefore, this work provides a facile strategy to achieve highly luminescent Au NCs via surface-confined emission enhancement imposed by ultrathin inorganic nanosheets, which can be potentially used in bio-imaging and cell labelling.


Subject(s)
Gold , Metal Nanoparticles , Nanostructures , Biocompatible Materials , Fluorescence , HeLa Cells , Humans
11.
J Surg Res ; 202(1): 216-24, 2016 May 01.
Article in English | MEDLINE | ID: mdl-27083969

ABSTRACT

BACKGROUND: Postsurgical peritoneal adhesion is a major clinical problem. Numerous anti-adhesion products have been studied, but none could be easily used to provide a physical barrier. In this study, we developed a "phase change" anti-adhesion barrier for reducing peritoneal adhesion by cross-linked copolymerization of O-carboxymethyl chitosan (CMC) and CaCl2 and addition of cyclosporin A (CsA). MATERIALS AND METHODS: The CMC-CaCl2-CsA compound was characterized by equilibrium swelling rate, weight loss, releasing effect, and coagulation test, and its biosafety was characterized by acute oral toxicity, hemolysis, and cytotoxicity. Intestinal adhesion model was applied on 64 Sprague-Dawley rats, which received CMC, CMC-CaCl2, or CMC-CaCl2-CsA treatment. At postoperative days 7 and 14, the rats were euthanized, and adhesions were graded by an investigator blinded to the treatment groups, using a predetermined adhesion scoring system. The cecum and adhesion tissue were stained with hematoxylin and eosin and antibodies for matrix metalloproteinase-9 and TIMP-1 for further histopathologic examination. RESULTS: The phase change anti-adhesive material exhibited effective blood clotting and were nontoxic in clotting experiments and acute toxicity test. The degradation rate could be adjusted using phosphate-buffered solution with varying pH. Adhesions were significantly reduced in the CMC-CaCl2-CsA treatment group compared with the control group (P < 0.001). Expression of matrix metalloproteinase-9 was stronger in CMC-CaCl2-CsA treatment group at 7 days after surgery. CONCLUSIONS: "Phase-change" adhesive can undergo changes after application, and it inhibits the formation of abdominal adhesions after surgery. The material is convenient for using by surgeons and provides an effective tool for intestinal adhesion prevention.


Subject(s)
Absorbable Implants , Calcium Chloride/therapeutic use , Chitosan/analogs & derivatives , Cyclosporine/therapeutic use , Peritoneal Diseases/prevention & control , Postoperative Complications/prevention & control , Tissue Adhesions/prevention & control , Animals , Biocompatible Materials/therapeutic use , Chitosan/therapeutic use , Drug Combinations , Female , Immunosuppressive Agents/therapeutic use , Intestines/surgery , Male , Peritoneal Diseases/etiology , Rats , Rats, Sprague-Dawley , Single-Blind Method , Tissue Adhesions/etiology , Treatment Outcome
12.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 29(6): 663-4, 2011 Dec.
Article in Chinese | MEDLINE | ID: mdl-22332587

ABSTRACT

The broken root dislocated into the maxillary sinus is a common complication during the teeth extraction. This article reported broken roots of four patients dislocated into maxillary sinus were removed successfully by endoscope under local anesthesia through windowing in inferior nasal meatus. It is an efficient method, which has less wounds and shorter surgical time.


Subject(s)
Maxillary Sinus , Tooth Root , Endoscopes , Humans , Tooth Extraction
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