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1.
Chin J Integr Med ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561489

RESUMO

Prostate cancer is a prevalent and debilitating disease that necessitates effective prevention and treatment strategies. Green tea, a well-known beverage derived from the Camellia sinensis plant, contains bioactive compounds with potential health benefits, including catechins and polyphenols. This comprehensive review aims to explore the potential benefits of green tea in prostate cancer prevention and treatment by examining existing literature. Green tea possesses antioxidant, anti-inflammatory, and anti-carcinogenic properties attributed to its catechins, particularly epigallocatechin gallate. Epidemiological studies have reported an inverse association between green tea consumption and prostate cancer risk, with potential protection against aggressive forms of the disease. Laboratory studies demonstrate that green tea components inhibit tumor growth, induce apoptosis, and modulate signaling pathways critical to prostate cancer development and progression. Clinical trials and human studies further support the potential benefits of green tea. Green tea consumption has been found to be associated with a reduction in prostate-specific antigen levels, tumor markers, and played a potential role in slowing disease progression. However, challenges remain, including optimal dosage determination, formulation standardization, and conducting large-scale, long-term clinical trials. The review suggests future research should focus on combinatorial approaches with conventional therapies and personalized medicine strategies to identify patient subgroups most likely to benefit from green tea interventions.

2.
Oncogene ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654108

RESUMO

Vascular endothelial cells (VECs) are key players in the formation of neovessels and tumor metastasis, the ultimate cause of the majority of cancer-related human death. However, the crosstalk between VECs and metastasis remain greatly elusive. Based on our finding that tumor-associated VECs present significant decrease of Nrdp1 protein which is closely correlated with higher metastatic probability, herein we show that the conditional medium from hypoxia-incubated cancer cells induces extensive Nrdp1 downregulation in human and mouse VECs by vascular endothelial growth factor (VEGF), which activates CHIP, followed by Nrdp1 degradation in ubiquitin-proteasome-dependent way. More importantly, lung metastases of cancer cells significantly increase in conditional VECs Nrdp1 knockout mice. Mechanically, Nrdp1 promotes degradation of Fam20C, a secretory kinase involved in phosphorylating numerous secreted proteins. Reciprocally, deficiency of Nrdp1 in VECs (ecNrdp1) results in increased secretion of Fam20C, which induces degradation of extracellular matrix and disrupts integrity of vascular basement membrane, thus driving tumor metastatic dissemination. In addition, specific overexpression of ecNrdp1 by Nrdp1-carrying adeno-associated virus or chemical Nrdp1 activator ABPN efficiently mitigates tumor metastasis in mice. Collectively, we explore a new mechanism for VEGF to enhance metastasis and role of Nrdp1 in maintaining the integrity of vascular endothelium, suggesting that ecNrdp1-mediated signaling pathways might become potential target for anti-metastatic therapies.

3.
Langmuir ; 40(16): 8665-8677, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38598258

RESUMO

In this study, a simple, green, and low-cost room temperature synthesis of broccoli-like silver nanoflowers (AgNF) with a particle size of about 300-500 nm was developed using plant-derived caffeic acid as a reducing agent and polyvinylpyrrolidone as a dispersant under ultrasound assistance. The flower clusters covered by small nanocrystals of 20-50 nm significantly enhance the electromagnetic field signals. AgNF was deposited on the surface of silicon wafers as a surface-enhanced Raman spectroscopy sensor for the detection of probe molecules such as rhodamine 6G (R6G) and malachite green with high sensitivity, homogeneity, and reproducibility. AgNF was deposited on cotton fabrics in the form of composites to catalyze the degradation of dye pollutants such as R6G, MG, and methyl orange in the presence of sodium borohydride. 0.1 g of AgNF/cotton fabric could assist 15 mmol/L NaBH4 to achieve over 90% degradation of various dyes as well as a high concentration of dyes in 12 min with good reusability and recyclability. The AgNF synthesized in this work can not only monitor the type and amounts of pollutants (dyes) in wastewater but also catalyze the rapid degradation of dyes, which is expected to be valuable for industrial applications.

4.
Langmuir ; 40(13): 7147-7157, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38520353

RESUMO

In this work, sea urchin-like magnetic Fe3O4@CA/BNNS/AgNP composite microspheres were successfully prepared. The photocatalytic performance of composite microspheres for the organic dye rhodamine B (RhB) was systematically investigated under different conditions, and the catalytic degradation rate of RhB was as high as 95% within 60 min; after three cycles of recycling, the degradation rate of RhB was reduced by only 8%. The main active agents in the reaction are e- and •O2-. Fe3O4@CA/BNNS/AgNP microspheres prepared in this study exhibit photocatalytic and electrochemical properties, making them easy to separate. This work is not limited to the development of Fe3O4-based catalysts but also is expected to provide ideas for the research and progress of photocatalytic composite catalysts with electrochemical properties.

5.
Int J Biol Macromol ; 266(Pt 1): 131140, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38537864

RESUMO

Conventional textile dyeing relies on the use of dyes and pigments, which can cause severe environmental contamination and waste a large amount of water. Structural coloring is one of the effective ways to achieve environmentally friendly coloring of textiles. In this work, three plant polyphenols with the same o-benzenetriol structure (tannic acid (TA), gallic acid (GA), and tea polyphenol (TP)) were selected as raw materials. Three plant polyphenols can quickly form nanofilms at the gas-liquid interface through a Schiff base reaction with polyethyleneimine (PEI) under mildly alkaline conditions, which were deposited to the surface of silk fabric, allowing precise control over the thickness of film by adjusting the time, resulting in various structurally colored silk fabric. This method for creating structural colors is not substrate-specific and enables the quick production of structural colors on various textile substrates. Furthermore, the structural color silk fabric based on plant polyphenol has antibacterial performance. This textile coloring method is simple, cost-effective and environmentally friendly, providing a new approach to eco-friendly textile dyeing.

6.
Int J Gen Med ; 17: 693-704, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435112

RESUMO

Background: Discordance between the anatomy and physiology of the coronary has important implications for managing patients with stable coronary disease, but its significance in ST-elevation myocardial infarction has not been fully elucidated. Methods: The retrospective study involved patients diagnosed with ST-elevation myocardial infarction (STEMI) who underwent percutaneous coronary intervention (PCI), along with quantitative coronary angiography (QCA) and quantitative flow ratio (QFR) assessments. Patients were stratified into four groups regarding the severity of the culprit vessel, both visually and functionally: concordantly negative (QCA-diameter stenosis [DS] ≤ 50% and QFR > 0.80), mismatch (QCA-DS > 50% and QFR > 0.80), reverse mismatch (QCA-DS ≤ 50% and QFR ≤ 0.80), and concordantly positive (QCA-DS > 50% and QFR ≤ 0.80). Multivariable logistic regression analyses were conducted to identify the clinical factors linked to visual-functional mismatches. Kaplan‒Meier analysis was conducted to estimate the 18-month adverse cardiovascular events (MACE)-free survival between the four groups. Results: The study involved 310 patients, with 68 presenting visual-functional mismatch, and 51 exhibiting reverse mismatch. The mismatch was associated with higher angiography-derived microcirculatory resistance (AMR) (adjusted odds ratio [aOR]=1.016, 95% CI: 1.010-1.022, P<0.001). Reverse mismatch was associated with larger area stenosis (aOR=1.044, 95% CI: 1.004-1.086, P=0.032), lower coronary flow velocity (aOR=0.690, 95% CI: 0.567-0.970, P<0.001) and lower AMR (aOR=0.947, 95% CI: 0.924-0.970, P<0.001). Additionally, the mismatch group showed the worst 18-month MACE-free survival among the four groups (Log rank test p = 0.013). Conclusion: AMR plays a significant role in the occurrence of visual-functional mismatches between QCA-DS and QFR, and the mismatch group showed the worst prognosis.

7.
Materials (Basel) ; 17(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38473686

RESUMO

Synthetic dyes are prone to water pollution during use, jeopardizing biodiversity and human health. This study aimed to investigate the adsorption and photocatalytic assist potential of sodium lignosulfonate (LS) in in situ reduced silver nanoparticles (AgNPs) and chitosan (CS)-loaded silver nanoparticles (CS-LS/AgNPs) as adsorbents for Rhodamine B (RhB). The AgNPs were synthesized by doping LS on the surface of chitosan for modification. Fourier transform infrared (FT-IR) spectrometry, energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to confirm the synthesis of nanomaterials. The adsorption and photocatalytic removal experiments of RhB were carried out under optimal conditions (initial dye concentration of 20 mg/L, adsorbent dosage of 0.02 g, time of 60 min, and UV power of 250 W), and the kinetics of dye degradation was also investigated, which showed that the removal rate of RhB by AgNPs photocatalysis can reach 55%. The results indicated that LS was highly effective as a reducing agent for the large-scale production of metal nanoparticles and can be used for dye decolorization. This work provides a new catalyst for the effective removal of dye from wastewater, and can achieve high-value applications of chitosan and lignin.

8.
Metab Eng ; 82: 238-249, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38401747

RESUMO

Ectoine, a crucial osmoprotectant for salt adaptation in halophiles, has gained growing interest in cosmetics and medical industries. However, its production remains challenged by stringent fermentation process in model microorganisms and low production level in its native producers. Here, we systematically engineered the native ectoine producer Halomonas bluephagenesis for ectoine production by overexpressing ectABC operon, increasing precursors availability, enhancing product transport system and optimizing its growth medium. The final engineered H. bluephagenesis produced 85 g/L ectoine in 52 h under open unsterile incubation in a 7 L bioreactor in the absence of plasmid, antibiotic or inducer. Furthermore, it was successfully demonstrated the feasibility of decoupling salt concentration with ectoine synthesis and co-production with bioplastic P(3HB-co-4HB) by the engineered H. bluephagenesis. The unsterile fermentation process and significantly increased ectoine titer indicate that H. bluephagenesis as the chassis of Next-Generation Industrial Biotechnology (NGIB), is promising for the biomanufacturing of not only intracellular bioplastic PHA but also small molecular compound such as ectoine.


Assuntos
Diamino Aminoácidos , Halomonas , Halomonas/genética , Diamino Aminoácidos/genética , Antibacterianos , Biopolímeros
9.
ACS Nano ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38323542

RESUMO

Autoimmune diseases, allergies, transplant rejections, generation of antidrug antibodies, and chronic inflammatory diseases have impacted a large group of people across the globe. Conventional treatments and therapies often use systemic or broad immunosuppression with serious efficacy and safety issues. Tolerogenic vaccines represent a concept that has been extended from their traditional immune-modulating function to induction of antigen-specific tolerance through the generation of regulatory T cells. Without impairing immune homeostasis, tolerogenic vaccines dampen inflammation and induce tolerogenic regulation. However, achieving the desired potency of tolerogenic vaccines as preventive and therapeutic modalities calls for precise manipulation of the immune microenvironment and control over the tolerogenic responses against the autoantigens, allergens, and/or alloantigens. Engineered nano-/microparticles possess desirable design features that can bolster targeted immune regulation and enhance the induction of antigen-specific tolerance. Thus, particle-based tolerogenic vaccines hold great promise in clinical translation for future treatment of aforementioned immune disorders. In this review, we highlight the main strategies to employ particles as exciting tolerogenic vaccines, with a focus on the particles' role in facilitating the induction of antigen-specific tolerance. We describe the particle design features that facilitate their usage and discuss the challenges and opportunities for designing next-generation particle-based tolerogenic vaccines with robust efficacy to promote antigen-specific tolerance for immunotherapy.

10.
Sci Rep ; 14(1): 4745, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413652

RESUMO

To compare the safety and effectiveness of the combination of intelligent intrarenal pressure control platforms (IPCP) and flexible ureteral access sheath (FUAS) combined with retrograde intrarenal surgery (RIRS) for the treatment of renal stones less than 2 cm. We retrospectively collected 383 patients with renal stones who underwent RIRS in our department from June 2022 to October 2023. Inclusion criteria: stone length or the sum of multiple stone lengths ≤ 2 cm. Finally, 99 cases were included and divided into an IPCP group (n = 40) and FUAS group (n = 59) based on surgical methods. The main endpoint was the stone-free rate (SFR) at third months after surgery, with no residual stones or stone fragments less than 2 mm defined as stone clearance. The secondary endpoints were surgical time and perioperative complications, including fever, sepsis, septic shock, and perirenal hematoma. There was no statistically significant difference in general information between the two groups, including age, gender, body mass index, comorbidities, stone side, stone location, stone length, urine bacterial culture, and hydronephrosis. The operation time for IPCP group and FUAS group was 56.83 ± 21.33 vs 55.47 ± 19.69 min (p = 0.747). The SFR of IPCP group and FUAS group on the first postoperative day was 75.00% vs 91.50% (p = 0.024). The SFR was 90.00% vs 94.90% in the third month (p = 0.349).In IPCP group, there were 11 cases with stones located in the lower renal calyces and 17 cases in FUAS group. The SFR of the two groups on the first day and third months after surgery were 45.50% vs 88.20% (p = 0.014) and 63.60% vs 94.10% (p = 0.040), respectively, with statistical differences. For kidney stones ≤ 2 cm, there was no difference in SFR and the incidence of infection-related complications between IPCP and FUAS combined with RIRS, both of which were superior to T-RIRS. For lower renal caliceal stones, FUAS has a higher SFR compared to IPCP.


Assuntos
Difosfonatos , Cálculos Renais , Ureteroscopia , Humanos , Ureteroscopia/efeitos adversos , Ureteroscopia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Cálculos Renais/cirurgia
11.
Cell Death Dis ; 15(2): 168, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395990

RESUMO

Glioblastoma (GBM) cells require large amounts of iron for tumor growth and progression, which makes these cells vulnerable to destruction via ferroptosis induction. Mitochondria are critical for iron metabolism and ferroptosis. Sirtuin-3 (SIRT3) is a deacetylase found in mitochondria that regulates mitochondrial quality and function. This study aimed to characterize SIRT3 expression and activity in GBM and investigate the potential therapeutic effects of targeting SIRT3 while also inducing ferroptosis in these cells. We first found that SIRT3 expression was higher in GBM tissues than in normal brain tissues and that SIRT3 protein expression was upregulated during RAS-selective lethal 3 (RSL3)-induced GBM cell ferroptosis. We then observed that inhibition of SIRT3 expression and activity in GBM cells sensitized GBM cells to RSL3-induced ferroptosis both in vitro and in vivo. Mechanistically, SIRT3 inhibition led to ferrous iron and ROS accumulation in the mitochondria, which triggered mitophagy. RNA-Sequencing analysis revealed that upon SIRT3 knockdown in GBM cells, the mitophagy pathway was upregulated and SLC7A11, a critical antagonist of ferroptosis via cellular import of cystine for glutathione (GSH) synthesis, was downregulated. Forced expression of SLC7A11 in GBM cells with SIRT3 knockdown restored cellular cystine uptake and consequently the cellular GSH level, thereby partially rescuing cell viability upon RSL3 treatment. Furthermore, in GBM cells, SIRT3 regulated SLC7A11 transcription through ATF4. Overall, our study results elucidated novel mechanisms underlying the ability of SIRT3 to protect GBM from ferroptosis and provided insight into a potential combinatorial approach of targeting SIRT3 and inducing ferroptosis for GBM treatment.


Assuntos
Ferroptose , Glioblastoma , Sirtuína 3 , Humanos , Sistema y+ de Transporte de Aminoácidos/genética , Cistina , Ferroptose/genética , Glioblastoma/genética , Glutationa , Indanos , Ferro , Mitofagia , Sirtuína 3/genética
12.
J Clin Neurosci ; 121: 11-17, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308978

RESUMO

BACKGROUND: Nervus intermedius neuralgia (NIN) is characterized by paroxysmal episodes of sharp, lancinating pain in the deep ear. Unfortunately, only a few studies exist in the literature on this pain syndrome, its pathology and postoperative outcomes. METHOD: We conducted a retrospective review of four cases diagnosed with NIN who underwent a neurosurgical intervention at our center from January 2015 to January 2023. Detailed information on their MRI examinations, intraoperative findings and other clinical presentations were obtained, and the glossopharyngeal and vagus nerves were isolated for immunohistochemistry examination. RESULTS: A total of 4 NIN patients who underwent a microsurgical intervention at our institution were included in this report. The NI was sectioned in all patients and 3 of them underwent a microvascular decompression. Of these 4 patients, 1 had a concomitant trigeminal neuralgia (TN), and 1 a concomitant glossopharyngeal neuralgia (GPN). Three patients underwent treatment for TN and 2 for GPN. Follow-up assessments ranged from 8 to 99 months. Three patients reported complete pain relief immediately after the surgery until last follow-up, while in the remaining patient the preoperative pain gradually resolved over the 3 month period. Immunohistochemistry revealed that a greater amount of CD4+ and CD8+ T cells had infiltrated the glossopharyngeal versus vagus nerve. CONCLUSIONS: NIN is an extremely rare condition showing a high degree of overlap with TN/GPN. An in depth neurosurgical intervention is effective to completely relieve NIN pain, without any serious complications. It appears that T cells may play regulatory role in the pathophysiology of CN neuralgia.


Assuntos
Doenças do Nervo Glossofaríngeo , Cirurgia de Descompressão Microvascular , Neuralgia , Neuralgia do Trigêmeo , Humanos , Nervo Facial , Linfócitos T CD8-Positivos , Neuralgia/etiologia , Neuralgia/cirurgia , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgia , Doenças do Nervo Glossofaríngeo/cirurgia , Resultado do Tratamento
13.
Nanoscale Adv ; 6(3): 876-891, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38298577

RESUMO

In this research, a molecular dynamics (MD) model was adopted to investigate the essence of the effect of strain rate on the mechanical behavior of the Fe14.6Ni (at%) elastocaloric refrigeration alloy. The study showed that the mechanical behavior of the Fe14.6Ni (at%) alloy was dependent on the strain rate. Besides, the investigation of temperature demonstrated that the strain rate influenced mechanical behavior by changing the transient temperatures. Furthermore, it was found that the adiabatic temperature change (ΔTadi) was high and up to 51 K, which was a 1.57 times improvement. Finally, the conclusion was drawn that the strain rate influenced the mechanical behavior by changing the transient total kinetic energy and the phase content evolution processes, which was the essence of the effect of strain rate on the mechanical behavior. This work has clarified the essence and enriched the theory of the effect of strain rate on the mechanical behavior of elastocaloric refrigeration alloys.

14.
J Clin Hypertens (Greenwich) ; 26(2): 134-144, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38192039

RESUMO

The authors aimed to investigate the association between outdoor light at night (LAN) intensity and blood pressure. The study included 13 507 participants aged 45 and above from the 2011-2012 China Health and Retirement Longitudinal Study baseline survey. Blood pressure measurements were obtained by averaging the last two readings recorded (three measurements with an interval of 45-60 s between each measurement) during the survey. Outdoor LAN intensity was assessed using Defense Meteorological Satellite Program data. The study categorized participants based on quartiles of outdoor LAN intensity and employed statistical methods like linear regression, restricted cubic splines, and logistic models to analyze the connections. After adjusting for potential confounding factors, higher levels of outdoor LAN intensity were associated with increase in systolic blood pressure (0.592 mmHg/interquartile range [IQR], 95% confidence interval [CI]: 0.027,1.157), diastolic blood pressure (0.853 mmHg/IQR, 95% CI: 0.525,1.180) and mean arterial pressure (0.766 mmHg/IQR, 95% CI: 0.385,1.147). Interestingly, the relationship between LAN intensity and odds of hypertension followed a non-linear pattern, resembling a reverse "L" shape on cubic splines. Participants with the highest quartile of outdoor LAN intensity had 1.31-fold increased odds of hypertension (95% CI: 1.08-1.58) compared to the lowest quartile. Additionally, there was an observable trend of rising odds for high-normal blood pressure with higher levels of LAN intensity in the crude model, but no statistically significant differences were observed after adjusting for confounding factors. In conclusion, this study underscores a significant connection between outdoor LAN intensity and the prevalence of hypertension.


Assuntos
Hipertensão , Adulto , Humanos , Hipertensão/epidemiologia , Hipertensão/etiologia , Pressão Sanguínea , Estudos Transversais , Estudos Longitudinais , China/epidemiologia
15.
Biotechnol Adv ; 71: 108320, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38272380

RESUMO

Polyhydroxyalkanoates (PHA) have evolved into versatile biopolymers, transcending their origins as mere bioplastics. This extensive review delves into the multifaceted landscape of PHA applications, shedding light on the diverse industries that have harnessed their potential. PHA has proven to be an invaluable eco-conscious option for packaging materials, finding use in films foams, paper coatings and even straws. In the textile industry, PHA offers a sustainable alternative, while its application as a carbon source for denitrification in wastewater treatment showcases its versatility in environmental remediation. In addition, PHA has made notable contributions to the medical and consumer sectors, with various roles ranging from 3D printing, tissue engineering implants, and cell growth matrices to drug delivery carriers, and cosmetic products. Through metabolic engineering efforts, PHA can be fine-tuned to align with the specific requirements of each industry, enabling the customization of material properties such as ductility, elasticity, thermal conductivity, and transparency. To unleash PHA's full potential, bridging the gap between research and commercial viability is paramount. Successful PHA production scale-up hinges on establishing direct supply chains to specific application domains, including packaging, food and beverage materials, medical devices, and agriculture. This review underscores that PHA's future rests on ongoing exploration across these industries and more, paving the way for PHA to supplant conventional plastics and foster a circular economy.


Assuntos
Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Biopolímeros , Alimentos
16.
Biomimetics (Basel) ; 9(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38248589

RESUMO

Traditional textile dyeing uses chemical pigments and dyes, which consumes a large amount of water and causes serious environmental pollution. Structural color is an essential means of achieving green dyeing of textiles, and thin-film interference is one of the principles of structural coloring. In the assembly of structural color films, it is necessary to introduce dark materials to suppress light scattering and improve the brightness of the fabric. In this study, the conditions for the generation of nanofilms of catechin (CC) at the gas-liquid interface were successfully investigated. At the same time, environmentally friendly colored silk fabrics were novelly prepared using polycatechin (PCC) structural color films. In addition, it was found that various structural colors were obtained on the surface of silk fabrics by adjusting the time. Meanwhile, the color fastness of the structural colored fabrics was improved by introducing polyvinylpyrrolidone (PVP) to form a strong hydrogen bond between the fabric and catechin. PCC film is uniform and smooth, with a special double-layer structure, and can be attached to the surface of silk fabrics, giving the fabrics special structural colors. Through the thin-film interference formed between the visible light and the PCC film, the silk fabrics obtain bright, controllable, and uniform structural colors. This method is easy to operate and provides a new way of thinking for environmental-protection-oriented coloring of fabrics.

17.
Carbohydr Polym ; 329: 121788, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286555

RESUMO

Additive manufacturing (AM) holds great potential for processing natural polymer hydrogels into 3D scaffolds exploitable for tissue engineering and in vitro tissue modelling. The aim of this research activity was to assess the suitability of computer-aided wet-spinning (CAWS) for AM of hyaluronic acid (HA)/chitosan (Cs) polyelectrolyte complex (PEC) hydrogels. A post-printing treatment based on HA chemical cross-linking via transesterification with poly(methyl vinyl ether-alt-maleic acid) (PMVEMA) was investigated to enhance the structural stability of the developed scaffolds in physiological conditions. PEC formation and the esterification reaction were investigated by infrared spectroscopy, thermogravimetric analysis, evolved gas analysis-mass spectrometry, and differential scanning calorimetry measurements. In addition, variation of PMVEMA concentration in the cross-linking medium was demonstrated to strongly influence scaffold water uptake and its stability in phosphate buffer saline at 37 °C. The in vitro cytocompatibility of the developed hydrogels was demonstrated by employing the murine embryo fibroblast Balb/3T3 clone A31 cell line, highlighting that PMVEMA cross-linking improved scaffold cell colonization. The results achieved demonstrated that the developed hydrogels represent suitable 3D scaffolds for long term cell culture experiments.


Assuntos
Quitosana , Camundongos , Animais , Quitosana/química , Ácido Hialurônico/química , Hidrogéis/química , Engenharia Tecidual/métodos , Linhagem Celular , Tecidos Suporte/química
18.
Curr Opin Biotechnol ; 85: 103064, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38262074

RESUMO

The use of extremophile organisms such as Halomomas spp. can eliminate the need for fermentation sterilization, significantly reducing process costs. Microbial fermentation is considered a pivotal strategy to reduce reliance on fossil fuel resources; however, sustainable processes continue to incur higher costs than their chemical industry counterparts. Most organisms require equipment sterilization to prevent contamination, a practice that introduces complexity and financial strain. Fermentations involving extremophile organisms can eliminate the sterilization process, relying instead on conditions that are conductive solely to the growth of the desired organism. This review discusses current challenges in pilot- and industrial-scale bioproduction when using the extremophile bacteria Halomomas spp. under nonsterile conditions.


Assuntos
Halomonas , Fermentação , Bactérias
20.
Metab Eng ; 81: 227-237, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38072357

RESUMO

5-Aminovaleric acid (5-AVA), 5-hydroxyvalerate (5HV), copolymer P(3HB-co-5HV) of 3-hydroxybutyrate (3HB) and 5HV were produced from L-lysine as a substrate by recombinant Halomonas bluephagenesis constructed based on codon optimization, deletions of competitive pathway and L-lysine export protein, and three copies of davBA genes encoding L-lysine monooxygenase (DavB) and 5-aminovaleramide amidohydrolase (DavA) inserted into its genome to form H. bluephagenesis YF117ΔgabT1+2, which produced 16.4 g L-1 and 67.4 g L-1 5-AVA in flask cultures and in 7 L bioreactor, respectively. It was able to de novo synthesize 5-AVA from glucose by L-lysine-overproducing H. bluephagenesis TD226. Corn steep liquor was used instead of yeast extract for cost reduction during the 5-AVA production. Using promoter engineering based on Pporin mutant library for downstream genes, H. bluephagenesis YF117 harboring pSEVA341-Pporin42-yqhDEC produced 6 g L-1 5HV in shake flask growth, while H. bluephagenesis YF117 harboring pSEVA341-Pporin42-yqhDEC-Pporin278-phaCRE-abfT synthesized 42 wt% P(3HB-co-4.8 mol% 5HV) under the same condition. Thus, H. bluephagenesis was successfully engineered to produce 5-AVA and 5HV in supernatant and intracellular P(3HB-co-5HV) utilizing L-lysine as the substrate.


Assuntos
Halomonas , Engenharia Metabólica , Lisina/genética , Lisina/metabolismo , Halomonas/genética , Halomonas/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Poliésteres/metabolismo , Porinas/genética , Porinas/metabolismo
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