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1.
J Pers Med ; 14(6)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38929840

RESUMO

This study compared the therapeutic effects of engineered exosomes derived from RAW264.7 cells overexpressing hsa-let-7i-5p (engineered exosomes) to exosomes from human placenta-derived mesenchymal stem cells (hpMSC exosomes) against sepsis-induced acute lung injury. Adult male C57BL/6 mice were divided into lipopolysaccharide (LPS), LPS plus engineered exosome (LEExo), or LPS plus hpMSC exosome (LMExo) groups, alongside control groups. The results showed that lung injury scores (based on pathohistological characteristics) and the levels of lung function alterations, tissue edema, and leukocyte infiltration in LEExo and LMExo groups were comparable and significantly lower than in the LPS group (all p < 0.05). Furthermore, the levels of inflammation (nuclear factor-κB activation, cytokine upregulation), macrophage activation (hypoxia-inducible factor-1α activation, M1 phase polarization), oxidation, and apoptosis were diminished in LEExo and LMExo groups compared to the LPS group (all p < 0.05). Inhibition of hsa-let-7i-5p attenuated the therapeutic effects of both engineered and hpMSC exosomes. These findings underscore the potent therapeutic capacity of engineered exosomes enriched with hsa-let-7i-5p and their potential as an alternative to hpMSC exosomes for sepsis treatment. Continued research into the mechanisms of action and optimization of engineered exosomes could pave the way for their future clinical application.

2.
Curr Microbiol ; 79(12): 389, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329346

RESUMO

ß-Indole acetic acid is produced in the rhizosphere by endophytic bacteria and promotes plant growth. Effects of bacterial IAA producers (BIPs) on plant growth and recovery of sugarcane seedlings infected with phytoplasma causing white leaf disease (SWLD) were examined. Fifty-five endophytic bacteria isolated from rice roots were collected from the Mekong River Delta, Vietnam. Seven isolates showed ß-Indole acetic acid production in culture medium supplemented with tryptophan. Interestingly, two of them (BC17 and BTII2) produced the highest ß-Indole acetic acid after 4 days of culture. Based on 16S rRNA sequences and phylogenetic analysis, the BC17 and BTII2 isolates were identified as Delftia lacustris and Rahnella aquatilis, respectively. Plant growth induced by the BC17 and BTII2 isolates showed statistically significant differences in height, root length and fresh weight of rice seedlings compared with non-treatment as the control. Treatment of two bacterial isolates in SWLD infected sugarcane plants also showed differences in height of sugarcane seedlings, while gradual symptoms of exposure decreased plant mortality compared to non-treatment as the control. BIPs were shown to be efficient biofertilizer inoculants that promoted plant growth and also ameliorated damage caused by phytoplasma-associated diseases at the sugarcane seedling stage.


Assuntos
Oryza , Saccharum , Saccharum/microbiologia , RNA Ribossômico 16S/genética , Filogenia , Ácidos Indolacéticos , Bactérias , Raízes de Plantas/microbiologia , Plântula , Oryza/microbiologia , Folhas de Planta
3.
Cureus ; 14(4): e24512, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35497086

RESUMO

Background Single-incision laparoscopic appendectomy (SILA) has recently emerged as a promising alternative for the management of acute appendicitis. This study aimed to compare the surgical outcomes of the SILA with those of three laparoscopic appendectomies (TLA) procedures using the existing equipment, the 10-mm laparoscope, and the surgical-glove port method. Methodology Between February 2021 and February 2022, this single-center retrospective study examined 68 patients who underwent laparoscopic appendectomy by a single surgeon. The study excluded patients with severe appendicitis, grade IV-V, following the American Association for the Surgery of Trauma classification. Clinical outcomes were analyzed, including operation time, hospital stay, postoperative pain, and postoperative morbidity. Results There were no statistically significant differences between SILA and TLA patients, respectively, in operation time (37.5 minutes vs. 35 minutes, p = 0.261) and the median duration of hospitalization (three days vs. three days, p = 0.929). There was no difference in the mean visual analog scale score between the two groups on the first day (p = 0.852), second day (p = 0.540), and the day of discharge from the hospital (p = 0.686), as well as return to diet (two days vs. two days, p = 0.053). Two (10%) cases of short-term complications in the SILA group and one (2.1%) case in the TLA group were noted. Conclusions SILA performed through a handmade surgical-glove port is a safe and viable therapy option for mild-to-moderate appendicitis. When the hospital lacks a specialized laparoscopic single-incision surgical system, this technique should be used on patients.

4.
J Hazard Mater ; 416: 126123, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492917

RESUMO

Toxicity biosensors have recently gained significant attention due to their potential use in online monitoring. However, the effects of toxicants and the influence of dose, exposure time, and type and concentration of respiration substrate (RS) on the performance of a bioreactor are species-specific. Although these factors need to be investigated case-by-case as they can lead either to damage or self-repair of the affected microorganisms, they have seldom been considered in previous studies. Therefore, this work examined, for the first time, the effects of resting time and RS concentration on the performance of the biosensing system for toxicity of Cr6+ in water. In addition, it is also the first time that a novel non-contact fluid delivery system was applied to a toxicity biosensing system to prevent unstable responses. By choosing the best RS concentration and balancing the resting and exposure times, the proposed procedure exhibits promising results in terms of minimum detectable concentration (MDC), limit of detection (LOD), detection range, linearity, sensitivity, reproducibility and accuracy. The recovery time was only a few hours and the coefficients of variation of inhibition and recovery were only 12% and 9.6%, respectively, during six times reuse over one month of storage.


Assuntos
Técnicas Biossensoriais , Metais Pesados , Intoxicação por Metais Pesados , Humanos , Metais Pesados/toxicidade , Reprodutibilidade dos Testes , Água
5.
Appl Microbiol Biotechnol ; 102(5): 2155-2165, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29372299

RESUMO

Avermectin produced by Streptomyces avermitilis is an anti-nematodal agent against the pine wood nematode Bursaphelenchus xylophilus. However, its potential usage is limited by its poor water solubility. For this reason, continuous efforts are underway to produce new derivatives that are more water soluble. Here, the enzymatic glycosylation of avermectin was catalyzed by uridine diphosphate (UDP)-glycosyltransferase from Bacillus licheniformis with various UDP sugars. As a result, the following four avermectin B1a glycosides were produced: avermectin B1a 4″-ß-D-glucoside, avermectin B1a 4″-ß-D-galactoside, avermectin B1a 4″-ß-L-fucoside, and avermectin B1a 4″-ß-2-deoxy-D-glucoside. The avermectin B1a glycosides were structurally analyzed based on HR-ESI MS and 1D and 2D nuclear magnetic resonance spectra, and the anti-nematodal effect of avermectin B1a 4″-ß-D-glucoside was found to exhibit the highest activity (IC50 = 0.23 µM), which was approximately 32 times greater than that of avermectin B1a (IC50 = 7.30 µM), followed by avermectin B1a 4″-ß-2-deoxy-D-glucoside (IC50 = 0.69 µM), avermectin B1a 4″-ß-L-fucoside (IC50 = 0.89 µM), and avermectin B1a 4″-ß-D-galactoside (IC50 = 1.07 µM). These results show that glycosylation of avermectin B1a effectively enhances its in vitro anti-nematodal activity and that avermectin glycosides can be further applied for treating infestations of the pine wood nematode B. xylophilus.


Assuntos
Anti-Helmínticos/farmacologia , Bacillus licheniformis/enzimologia , Proteínas de Bactérias/metabolismo , Glicosídeos/farmacologia , Glicosiltransferases/metabolismo , Ivermectina/análogos & derivados , Pinus/parasitologia , Doenças das Plantas/parasitologia , Tylenchida/efeitos dos fármacos , Animais , Anti-Helmínticos/química , Anti-Helmínticos/metabolismo , Bacillus licheniformis/metabolismo , Proteínas de Bactérias/química , Glicosídeos/química , Glicosídeos/metabolismo , Glicosiltransferases/química , Ivermectina/química , Ivermectina/metabolismo , Ivermectina/farmacologia , Doenças das Plantas/prevenção & controle , Tylenchida/fisiologia
6.
Nat Prod Res ; 32(15): 1782-1790, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29156984

RESUMO

Screening for new natural anti-neuroinflammatory compounds was performed with the traditional folk medicine Genkwa Flos, which potently inhibited nitric oxide (NO) production by LPS-activated microglial BV-2 cells. Two new lathyrane-type diterpenes, genkwalathins A (1) and B (2), and 14 known daphnane-type diterpenes (3-16) were isolated. The lathyrane-type diterpenes were isolated for the first time from the Thymelaeaceae family in this study. Compounds 1 and 2 moderately inhibited LPS-induced NO production in BV-2 cells without affecting cell viability, while six daphnane-type diterpenes (3, 4, 6, 7, 9 and 10) potently reduced NO production with IC50 values less than 1 µM, although they did display weak cytotoxicity. A structure-activity relationship study on the daphnane-type diterpenes indicated that the stereochemistry at C-19, the benzoate group at C-20, and the epoxide moiety could be important for their anti-neuroinflammatory effects.


Assuntos
Daphne/química , Diterpenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/química , Avaliação Pré-Clínica de Medicamentos , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Microglia/citologia , Estrutura Molecular , Óxido Nítrico/metabolismo , Relação Estrutura-Atividade , Thymelaeaceae/química
7.
J Food Sci Technol ; 54(7): 1850-1856, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28720940

RESUMO

Shrimp heads are considered as a potential source for the recovery of many valuable components such as chitin, protein and carotenoids. In the present study, both protein hydrolysate and chitin/chitosan were recovered using combination of physical, biological and chemical treatments. Shrimp heads were separated from liquid phase by a facile and efficient physical pretreatment. The liquid fraction was then hydrolyzed using formic acid and vacuum concentrated to obtain an astaxanthin-rich protein hydrolysate. The solid fraction was used to produce chitin by deproteination and demineralization. The hydrolysate consisted of a high astaxanthin (192 ppm) and protein (26.3 wt%) content. Chitosan prepared from chitin showed a high degree of deacetylation (85.4%) with low protein (0.25 wt%) and mineral (0.22 wt%) contents. The relative crystalline structure of the chitin and chitosan were 54.7 and 10.4%, respectively. The deacetylation of chitin was confirmed by Fourier Transform Infrared Spectroscopy. The present procedure approached to produce maximum valuable components including astaxanthin-rich protein hydrolysate and chitin/chitosan from shrimp head waste.

8.
Mycobiology ; 45(1): 44-47, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28435354

RESUMO

Ginseng damping-off, caused by the fungal pathogens Rhizoctonia solani and Pythium sp., is a critical disease in ginseng seedling. In a continuing effort to find microorganisms with the potential of acting as a biocontrol agent against Rhizoctonia damping-off, we found that a Streptomyces sp. A501 showed significant antifungal activity against Rhizoctonia solani. In field experiment to test the efficacy of Streptomyces sp. A501 in controlling ginseng damping-off, the incidence of damping-off disease was meaningfully reduced when ginseng seeds were soaked in the culture broth of Streptomyces sp. A501 before sowing. To perform characterization of the antifungal compound, we isolated it from the culture broth of strain A501 through Diaion HP-20 and silica gel column chromatographies and preparative high-performance liquid chromatography. The structure of the antifungal compound was assigned as fungichromin by spectroscopic methods, mainly nuclear magnetic resonance and electrospray ionization-mass analysis.

9.
Am J Phys Anthropol ; 163(2): 285-294, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28299780

RESUMO

OBJECTIVES: The degree of expression of sulcal patterns on endocasts of nonhuman primates has been shown to depend primarily on species (brain size) and age of the individual. It has been suggested that brain details on endocasts are reproduced better in juvenile than adult primates. Here, we investigated age-related changes in the imprint of the major sulci on the endocranium of Japanese macaques (Macaca fuscata) from the juvenile period to adulthood. MATERIALS AND METHODS: Using CT scans of 25 (12 males, 13 females) cranial specimens from macaques, we generated virtual endocasts to assess imprints of the seven main sulci on the endocranial surface. Expression of each sulcal imprint was evaluated by imprint score method. RESULTS: The degree of expression of sulcal imprints differed between sulci. Arcuate, superior temporal, and principal sulci were well defined, whereas lunate and intraparietal sulci were poorly represented. Sulcal imprints showed significant age-related changes in Japanese macaques from juvenile to elderly. Sulcal imprints showed a slight decrease in degree of expression from the juvenile period (2-4 years) to adolescence (4-6 years), and then remained unchanged until mid-adulthood (15-16 years). The degree of expression of the sulcal imprints significantly decreased from mid-adulthood to old age (>20 years). CONCLUSIONS: The degree of expression of the sulcal imprints (relief forms) in inner table bone surface (endocranium) reveals significant age-related decreases in adults. The great decrease starts at around 20 years of age. The endocranial volume showed a significant age-related increase, and thus, it is suggested that the endocranial surface in macaques may be resorbed with advancing age.


Assuntos
Envelhecimento/fisiologia , Encéfalo/anatomia & histologia , Macaca/anatomia & histologia , Crânio/anatomia & histologia , Animais , Antropologia Física , Feminino , Masculino
10.
Mycobiology ; 43(3): 333-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26539051

RESUMO

In a previous study, we identified a Streptomyces sp., A3265, as exhibiting potent antifungal activity against various plant pathogenic fungi, including Botrytis cinerea, Colletotrichum gloeosporioides, and Rhizoctonia solani. This strain also exhibited a biocontrolling effect against ginseng root rot and damping-off disease, common diseases of ginseng and other crops. In this study, we isolated two antifungal substances responsible for this biocontrolling effect via Diaion HP-20 and Sephadex LH-20 column chromatography, medium pressure liquid chromatography, and high-performance liquid chromatography. These compounds were identified as guanidylfungin A and methyl guanidylfungin A by spectroscopic methods. These compounds exhibited potent antimicrobial activity against various plant pathogenic fungi as well as against bacteria.

11.
J Nanosci Nanotechnol ; 11(7): 6494-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22121743

RESUMO

To extend the light absorption of TiO2-based photocatalysts towards the visible-light range and to eliminate the rapid recombination of excited electrons/holes during photoreaction, a new type of photocatalyst (N-doped TiO2) powder was prepared through a simple sol-gel process. The crystal phase composition, structure, and light absorption of the new photocatalyst were comprehensively examined via X-ray diffraction, ultraviolet-visible (UV-Vis) absorption spectroscopy, and atomic-absorption spectroscopy. The photo-oxidation efficiency of the photocatalyst was also evaluated in the photodegradation of methylene blue (MB) and of phenol in aqueous solutions under visible-light irradiation from a neon lamp (lambda > 400 nm). The results of the analyses that were performed in this study indicated that the N-doped TiO2 could eliminate the electron/holes recombination and could increase the light absorption in the visible range. The results of the analysis of the UV-Vis diffuse reflection and optical-absorption spectra indicated that a new energy level below 3.2 eV generated in the N-doped TiO2 promoted the optical absorption in the visible-light region and made visible-light excitation possible (E < 3.2 eV). The experiment demonstrated that the photo-oxidation efficiency of MB when N-doped TiO2 powder was used was significantly higher than that when the conventional TiO2 powders were used. The development of such photocatalyst may be considered a breakthrough in the large-scale utilization of solar energy to address the current and future environmental needs.

12.
PLoS One ; 4(12): e8052, 2009 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-19997610

RESUMO

Cooperative activation of striated muscle by calcium is based on the movement of tropomyosin described by the steric blocking theory of muscle contraction. Presently, the Hill model stands alone in reproducing both myosin binding data and a sigmoidal-shaped curve characteristic of calcium activation (Hill TL (1983) Two elementary models for the regulation of skeletal muscle contraction by calcium. Biophys J 44: 383-396.). However, the free myosin is assumed to be fixed by the muscle lattice and the cooperative mechanism is based on calcium-dependent interactions between nearest neighbor tropomyosin subunits, which has yet to be validated. As a result, no comprehensive model has been shown capable of fitting actual tension data from striated muscle. We show how variable free myosin is a selective advantage for activating the muscle and describe a mechanism by which a conformational change in tropomyosin propagates free myosin given constant total myosin. This mechanism requires actin, tropomyosin, and filamentous myosin but is independent of troponin. Hence, it will work equally well with striated, smooth and non-muscle contractile systems. Results of simulations with and without data are consistent with a strand of tropomyosin composed of approximately 20 subunits being moved by the concerted action of 3-5 myosin heads, which compares favorably with the predicted length of tropomyosin in the overlap region of thick and thin filaments. We demonstrate that our model fits both equilibrium myosin binding data and steady-state calcium-dependent tension data and show how both the steepness of the response and the sensitivity to calcium can be regulated by the actin-troponin interaction. The model simulates non-cooperative calcium binding both in the presence and absence of strong binding myosin as has been observed. Thus, a comprehensive model based on three well-described interactions with actin, namely, actin-troponin, actin-tropomyosin, and actin-myosin can explain the cooperative calcium activation of striated muscle.


Assuntos
Contração Isométrica/fisiologia , Tono Muscular/fisiologia , Músculo Estriado/fisiologia , Animais , Cálcio/metabolismo , Fluorescência , Modelos Biológicos , Miosinas/metabolismo , Oxidiazóis/metabolismo , Ligação Proteica
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