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1.
Plant Physiol Biochem ; 212: 108736, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797006

RESUMO

Due to the damaging effect of high temperatures on plant development, global warming is predicted to increase agricultural risks. Chinese cabbage holds considerable importance as a leafy vegetable that is extensively consumed and cultivated worldwide. Its year-round production also encounters severe challenges in the face of high temperatures. In this study, melatonin (MT), a pivotal multifunctional signaling molecule that coordinates responses to diverse environmental stressors was used to mitigate the harmful effects of high temperatures on Chinese cabbage. Through the utilization of growth indices, cytological morphology, physiological and biochemical responses, and RNA-Seq analysis, alongside an examination of the influence of crucial enzymes in the endogenous MT synthesis pathway on the thermotolerance of Chinese cabbage, we revealed that MT pretreatment enhanced photosynthetic activity, maintained signaling pathways associated with endoplasmic reticulum protein processing, and preserved circadian rhythm in Chinese cabbage under high temperatures. Furthermore, pretreatment with MT resulted in increased levels of soluble sugar, vitamin C, proteins, and antioxidant enzyme activity, along with decreased levels of malondialdehyde, nitrate, flavonoids, and bitter glucosinolates, ultimately enhancing the capacity of the organism to mitigate oxidative stress. The knockdown of the tryptophan decarboxylase gene, which encodes a key enzyme responsible for MT biosynthesis, resulted in a significant decline in the ability of transgenic Chinese cabbage to alleviate oxidative damage under high temperatures, further indicating an important role of MT in establishing the thermotolerance. Taken together, these results provide a mechanism for MT to improve the antioxidant capacity of Chinese cabbage under high temperatures and suggest beneficial implications for the management of other plants subjected to global warming.


Assuntos
Antioxidantes , Brassica , Melatonina , Termotolerância , Melatonina/metabolismo , Melatonina/farmacologia , Antioxidantes/metabolismo , Termotolerância/efeitos dos fármacos , Brassica/metabolismo , Brassica/efeitos dos fármacos , Brassica/genética , Temperatura Alta , Estresse Oxidativo/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
2.
Fish Shellfish Immunol ; 141: 109011, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37604263

RESUMO

The intestine is a host-pathogen interaction site and improved intestinal barrier function help to prevent disease in shrimp. Alginate oligosaccharides (AOS) are derived from resourceful brown algae. The intestine protection properties of AOS were widely recognized, and their benefits in fish have been reported. Nevertheless, there are no reports on AOS in shrimp and other crustaceans. In the present work, we measured the effects of AOS on growth performance and disease resistance in the white shrimp Litopenaeus vannamei and investigated their effects on intestinal health. Shrimps with an initial weight of about 2 g were fed with diets supplemented with 0 (control), 0.07%, 0.2%, 0.6%, or 1.2% of AOS for 56 days and were sampled and challenged with Vibrio parahaemolyticus. Dietary AOS did not significantly influence weight gain or feed utilization (P > 0.05). However, AOS considerably decreased the seven-day cumulative mortality after the challenge at any dose (P < 0.05). Dietary AOS improved the intestinal structure, significantly boosted the intestinal villus height at 0.6% and 1.2% levels, and increased intestinal wall thickness by 0.2%, 0.6%, and 1.2%. The alkaline phosphatase and maltase activities were also increased, suggesting that AOS improved the intestinal condition. Redox homeostasis in intestinal was improved by AOS, as expressed by the enhanced total antioxidant capacity and decreased malonaldehyde content, partly due to the increased superoxide dismutase and catalase activities. Compared with the antioxidant system, AOS's stimulating effects on immunity were more significant. At any level, AOS significantly activated lysozyme activity, the expression of propo and two antimicrobial peptide genes (pen-3 and crusin). However, the lowest concentration of AOS did not stimulate the gene expression of all three assayed pattern recognition receptors (LGBP, Toll, and IMD), and only the highest concentration of AOS increased the expression of imd. These findings suggest that AOS are highly efficient immunostimulants, and various immune pathways in shrimp are differentially sensitive to AOS. Finally, our findings suggest that AOS significantly alter the gut microbiota and their relative abundance at the phylum, family, and genus levels. In conclusion, AOS significantly enhances disease resistance in L. vannamei, possibly attributed to improved intestinal development, increased intestinal immunity and altered microbiota. These findings could provide a basis for future studies on the practical use of AOS and its mechanisms of action.


Assuntos
Enteropatias , Penaeidae , Vibrio parahaemolyticus , Animais , Resistência à Doença , Antioxidantes/farmacologia , Alginatos/farmacologia , Imunidade Inata , Dieta/veterinária , Intestinos , Oligossacarídeos/farmacologia , Ração Animal/análise
3.
Int J Biol Macromol ; 240: 124365, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37030460

RESUMO

Wound dressing with an improved structural and functional recapitulation of damaged organs, efficient self-healing and antibacterial properties that can well integrate with tissue are urgently needed in wound management. Supramolecular hydrogels confer control over structural properties in a reversible, dynamic and biomimetic fashion. Herein, a kind of injectable, self-healing and antibacterial supramolecular hydrogel with multi-responses were fabricated by mixing phenylazo-terminated Pluronic F127, quaternized chitosan-graft-cyclodextrin and polydopamine coated tunicate cellulose nanocrystals under physiological conditions. By exploiting the photoisomerization of azobenzene under different wavelengths, a supramolecular hydrogel featuring a changing crosslink density of network was obtained. The corporation of polydopamine coated tunicate cellulose nanocrystals strengthens the hydrogel network with Schiff base bonds and hydrogen bonds, which avoids complete gel-sol transition. The inherent antibacterial property, drug release behavior, self-healing ability, hemostatic performance and biocompatibility were investigated to confirm superiority in wound healing. Moreover, the curcumin loaded hydrogel (Cur-hydrogel) showed multi-responsive release profiles (light, pH, and temperature). A full-thickness skin defect model was built to confirm that Cur-hydrogels significantly accelerated wound healing rate with better granulation tissue thickness and collagen disposition. Overall, the novel photo-responsive hydrogel with coherent antibacterial property has great potential in the healthcare of wound healing.


Assuntos
Quitosana , Nanopartículas , Hidrogéis/farmacologia , Hidrogéis/química , Celulose , Bandagens , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química
4.
J Sci Food Agric ; 103(10): 5087-5095, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36991224

RESUMO

BACKGROUND: Mycosporine-like amino acids (MAAs) are known as the strongest solar guardians in nature. RESULTS: In the present study, the extraction of MAAs from dried Pyropia haitanensis was achieved. Fish gelatin and oxidized starch composite films embedded with MAAs (0-0.3% w/w) were fabricated. The maximum absorption wavelength of the composite film appeared at 334 nm, which was consistent with MAA solution. Furthermore, the UV absorption intensity of the composite film was highly dependent on the concentration of MAAs. The composite film exhibited excellent stability during the 7-day storage period. The physicochemical features of composite film were demonstrated by the measurement of water content, water vapor transmission rate, oil transmission, and visual characteristics. Furthermore, in the actual anti-UV effect investigation, the increase in peroxide value and the acid value of grease under the films coverage was delayed. In the meantime, the decrease in ascorbic acid content in dates was postponed, and survivability of Escherichia coli was increased. CONCLUSION: Our results suggest that fish gelatin-oxidized starch-mycosporine-like amino acids film (FOM film) with biodegradable and anti-ultraviolet properties has a high potential for usage in food packaging materials. © 2023 Society of Chemical Industry.


Assuntos
Peixes , Animais , Gelatina/química , Aminoácidos/química , Raios Ultravioleta , Amido/química , Ácido Ascórbico/química
5.
Scanning ; 2022: 8762504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238759

RESUMO

In order to meet the needs of modern people for the acquisition of intangible cultural heritage information, the authors propose a research method that combines 3D scanning and virtual reality technology. Taking the production process of Xiuyu as an example, using Unity3D virtual reality technology combined with a digital platform, 3D modeling of Xiuyu is carried out, so that people can view the intangible cultural heritage information intuitively. The experimental results show that after using this method, more than 60% of more than 1000 people surveyed in the questionnaire want to experience intangible cultural heritage. In a survey of visualization platforms conducted at the same time, 90% of users are willing to combine jade carving technology with 3D scanning virtual reality technology. Conclusion. 3D scanning and virtual reality technology can further promote the process of inheritance and dissemination of intangible cultural heritage, accelerate the cultivation of intangible cultural heritage talents through the visualization platform, and promote the sustainable development of intangible cultural heritage, in order to better pass down the life memory and cultural genes of our ancient nation.


Assuntos
Realidade Virtual , Humanos , Tecnologia
6.
Int J Mol Sci ; 23(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36012648

RESUMO

Salecan (Sal) is a novel marine microbial polysaccharide. In the present research, Sal and soy protein isolate (SPI) were adopted to fabricate Sal-SPI composite hydrogel based on a stepwise process (thermal treatment and transglutaminase induction). The effect of Sal concentration on morphology, texture properties, and the microstructure of the hydrogel was evaluated. As Sal concentration varied from 0.4 to 0.6 wt%, hydrogel elasticity increased from 0.49 to 0.85 mm. Furthermore, the internal network structure of Sal-SPI composite hydrogel also became denser and more uniform as Sal concentration increased. Rheological studies showed that Sal-SPI elastic hydrogel formed under the gelation process. Additionally, FTIR and XRD results demonstrated that hydrogen bonds formed between Sal and SPI molecules, inferring the formation of the interpenetrating network structure. This research supplied a green and simple method to fabricate Sal-SPI double network hydrogels.


Assuntos
Hidrogéis , beta-Glucanas , Hidrogéis/química , Proteínas de Soja/metabolismo , Transglutaminases/metabolismo , beta-Glucanas/química
7.
Pharmaceutics ; 14(7)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35890387

RESUMO

Salecan (Sal) is a novel microbial polysaccharide. In the present research, thermal treatment was performed to fabricate Sal hydrogel. The effect of Sal concentration on water holding capacity, swelling properties, texture properties, and microstructure of the hydrogels was discussed. It was found that the equilibrium degree of swelling (EDS) of Sal hydrogels was above 1500%, inferred Sal was a highly hydrophilic polysaccharide. As Sal concentration increased from 3.5 to 8.0 wt%, the hardness increased from 0.88 to 2.07 N and the water hold capability (WHC) increased from 91.3% to 98.2%. Furthermore, the internal network structure of Sal hydrogel also became denser and more uniform. Rheological studies suggested that elastic hydrogel formed under the gelation process. All these results demonstrated that Sal hydrogel prepared by thermal treatment had good gelling properties, which opened up a new safe way for the preparation of Sal hydrogel and broadened the application range of Sal.

8.
Polymers (Basel) ; 14(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35893944

RESUMO

Mycosporine-like amino acids (MAAs) are ultraviolet-absorbing compounds and have antioxidant functions. In this paper, MAAs were added into fish gelatin/sodium alginate films as an anti-ultraviolet additive. The effects of 0-5% MAAs (w/w, MAAs/fish gelatin) on the physical properties, antioxidant properties, antibacterial properties and anti-ultraviolet properties of fish gelatin/sodium alginate films were investigated. The results suggest that the content of the MAAs influenced the mechanical properties. The water content, swelling and water vapor permeability of the films were not altered with the addition of MAAs. In addition, the composite films showed effective antioxidant activity and antimicrobial activity. The incorporation of MAAs significantly improved the DPPH radical scavenging activity of the films from 35.77% to 46.61%. Moreover, the block ultraviolet rays' ability was also greatly improved when the film mixed with the MAAs and when the value of the light transmission was 0.6% at 350 nm. Compared with the pure composite film, the growth of E. coli covered by the composite film with 3.75% and 5% MAAs exhibited the best survival rate. These results reveal that MAAs are a good film-forming substrate, and MAAs have good potential to prepare anti-ultraviolet active films and antioxidant active films for applications. Overall, this project provides a theoretical basis for the study of active composite films with anti-ultraviolet activities, and it provides new ideas for the application of MAAs.

9.
Pharmaceuticals (Basel) ; 15(2)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35215318

RESUMO

Microneedles are one promising penetration enhancement vehicle to overcome the stratum corneum skin barrier, which hampers the penetration of drug nanocrystals by transdermal delivery. In order to clarify the particle size effect of nanocrystals on transdermal delivery, 60 nm, 120 nm, and 480 nm curcumin nanocrystals were fabricated and incorporated into dissolving hyaluronic acid polysaccharide microneedles. The microneedles showed good mechanical strength with 1.4 N/needle, possessing the ability to insert into the skin. The passive permeation results showed that the smaller particle size of 60 nm curcumin nanocrystals diffused faster and deeper than the larger 120 nm and 480 nm curcumin nanocrystals with size-dependent diffusion behaviors. Thereafter, higher concentration gradients and overlap diffusional coronas also formed in the skin layers by the smaller-particle-size nanocrystals. Furthermore, the diffusion rate of the smaller particle size of curcumin nanocrystals to the hair follicle was also higher than that of the larger curcumin nanocrystals. In conclusion, the particle sizes of curcumin nanocrystals influenced the transdermal and transfollicular penetration in deeper skin layers.

10.
Fish Shellfish Immunol ; 119: 373-378, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688862

RESUMO

Soya-saponins represent key anti-nutritional factors that contribute to soybean meal-induced enteritis, and glutamine is an effective fish intestine protectant that combats the negative effects of soya-saponins. Nuclear transcription factor-kappa B (NF-кB) systems are involved in the interactions between soya-saponins and glutamine, and the goal of the present work was to clarify the related molecular mechanisms used by the NF-кB kinase (IKK)/inhibitor of NF-κB (IκB)/NF-кB system. Primary cultured turbot (Scophthalmus maximus L.) intestinal epithelial cells were concurrently administrated with 1 mg/mL of soya-saponins and several levels of glutamine (0, 0.5, 1.0 and 2.0 mM) for 12 h and then subjected to real-time PCR and Western blot assays. Compared with cells treated with soya-saponins alone, glutamine significantly decreased the expression of interleukin-1 beta, interleukin 8 and tumor necrosis factor α genes, significantly reduced nuclear and cytosolic NF-κB p65 abundance levels in a dose-dependent manner, increased the IκBα protein level but decreased its phosphorylation, and down-regulated the IKKα/ß and phosphorylated IKKα/ß levels. In conclusion, this in vitro work confirmed that glutamine attenuated soya-saponin-induced inflammatory responses in turbot intestines. Moreover, it identified molecular pathways in which glutamine first decreased the p65 level and then prevented its nuclear translocation. In addition, glutamine reduced IκBα phosphorylation and maintained its level. Finally, glutamine decreased IKK expression and phosphorylation.


Assuntos
Linguados , Saponinas , Animais , Enterócitos , Glutamina , Quinase I-kappa B/genética , Proteínas I-kappa B , Inibidor de NF-kappaB alfa/genética , NF-kappa B/genética , Glycine max
11.
Fish Shellfish Immunol ; 114: 49-57, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887442

RESUMO

Soy saponins, as thermo-stable anti-nutrients in soybean meal (SBM), are the primary causal agents of SBM-induced enteritis, which represents a well-documented pathologic alternation involving the distal intestines of various farmed fish. Our previous work showed that soy saponins might lead to SBM-induced enteritis, destroy tight junction structure and induce oxidative damage in juvenile turbot. Glutamine, as a conditionally essential amino acid, is an important substrate utilized for the growth of intestinal epithelial cells. An 8-week feeding trial was carried out to determine whether glutamine can attenuate the detrimental effects of soy saponins. Three isonitrogenous-isolipidic experimental diets were formulated as follows: (i) fish meal-based diet (FM), considered as control; (ii) FM + 10 g/kg soy saponins, SAP; and (iii) SAP + 15 g/kg glutamine, GLN. The results showed that dietary soy saponins significantly increased the gene expression levels of inflammatory markers (IL-1ß, IL-8 and TNF-α) and related signaling factors (NF-кB, AP-1, p38, JNK and ERK), which were remarkably attenuated by dietary glutamine. Compared to SAP group, GLN-fed fish exhibited significantly higher expression levels of tight junction genes (CLDN3, CLDN4, OCLN, Tricellulin and ZO-1). Glutamine supplementation in SAP diet markedly suppressed the production of reactive oxygen species, malondialdehyde and protein carbonyl, and enhanced the activities of antioxidant enzymes as well as the mRNA levels of HO-1, SOD, GPX and Nrf2. Furthermore, GLN-fed fish had a remarkably lower number of autophagosomes compared to SAP-fed fish. In conclusion, our study indicated that glutamine could reverse the harmful effects of soy saponins on intestinal inflammation, tight junction disruption and oxidative damage, via attenuation of NF-кB, AP-1 and MAPK pathways and activation of Nrf2 pathway. Glutamine may have the function of controlling autophaghic process within an appropriate level of encountering inflammation.


Assuntos
Enterite/induzido quimicamente , Doenças dos Peixes/induzido quimicamente , Linguados/fisiologia , Glutamina/farmacologia , Glycine max/química , Saponinas/toxicidade , Ração Animal/análise , Animais , Autofagia/efeitos dos fármacos , Dieta/veterinária , Enterite/prevenção & controle , Doenças dos Peixes/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos
12.
Br J Nutr ; 126(11): 1651-1662, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33550994

RESUMO

An 8-week feeding experiment was conducted to investigate and confront the putative functions of chitosan (CTS) and chitooligosaccharide (COS) in the growth and homoeostasis of distal intestine in juvenile turbots fed diets containing soyabean meal (SBM). Three isolipidic and isonitrogenous diets were formulated by supplemented basal diet (based on a 400 g/kg SBM) with 7·5 g/kg CTS or with 2·0 g/kg COS. Our results indicated that both CTS and COS supplementation could significantly improve (i) the growth performance and feed efficiency ratio; (ii) antioxidant activity driven by metabolic enzymes (i.e. catalase, glutathione reductase, glutathione peroxidase and superoxide dismutase); (iii) glutathione levels; (iv) acid phosphatase and lysozyme activity and (v) IgM content. As a result, these two particular prebiotics were able to significantly attenuate the histological alterations due to local inflammation as well as to decrease the transcriptional levels of proinflammatory cytokines (i.e. IL-1ß, IL-8 and TNF-α) and major pathway effectors (i.e. activator protein-1 (AP-1), NF-кB, p38 mitogen-activated protein kinase, c-Jun N-terminal kinase and extracellular regulated kinase). High-throughput sequencing data indicated that dietary CTS and COS could significantly decrease the diversity of intestinal bacteria but elevate the relative abundances of Bacillus, Lactobacillus and Pseudomonas genera. Altogether, these findings suggest that CTS and COS can improve growth of turbot, enhance intestinal immune and anti-oxidant systems and promote the balance of intestinal microbiota. The protective effects, elicited by these two prebiotics, against SBM-induced inflammation could be attributed to their roles in alleviating the overexpression of inflammatory cytokines by possibly down-regulating NF-кB, AP-1 and/or mitogen-activated protein kinases pathways.


Assuntos
Quitosana , Linguados , Ração Animal/análise , Animais , Quitosana/efeitos adversos , Dieta , Suplementos Nutricionais , Inflamação/induzido quimicamente , Proteínas Quinases Ativadas por Mitógeno , NF-kappa B , Oligossacarídeos , Fator de Transcrição AP-1
13.
PLoS One ; 14(3): e0213867, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30865702

RESUMO

Corn gluten meal (CGM) is an important alternative protein source in aquafeed production. However, in turbot (Scophthalmus maximus), CGM could not be effectively utilized because of its low digestibility, the reason for which is still unclear. The purpose of the present study was to investigate and elucidate the cause for the poor utilization of CGM by turbot from the view of gut health. An 8-week feeding trial was conducted with turbot individuals (initial body weight 11.4 ± 0.2 g), which were fed with one of four isonitrogenous and isolipidic diets formulated to include 0%, 21.2%, 31.8%, and 42.6% CGM to progressively replace 0%, 33%, 50%, and 67% fish meal (FM) protein in a FM-based diet, respectively. The results showed that CGM caused dose-dependent decreases in (1) growth performance, nutrient digestibility, and feed utilization; (2) activities of brush-border membrane enzymes; (3) intestinal antioxidant indices of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase activities, and reduced glutathione level; (4) intestinal immune parameters of acid phosphatase activity, complement 3, complement 4, and IgM concentrations. Dose-dependent increases in the severity of the inflammation, with concomitant alterations on microvilli structure and increasing expression of inflammatory cytokine genes of Il-1ß, Il-8, and Tnf-α were observed but without a change in the intracellular junctions and the epithelial permeability established by the plasma diamine oxidase activity and D-lactate level examinations. In conclusion, the present work proved that CGM negatively affected the gut health of turbot by inducing enteritis and by decreasing intestinal immunity and antioxidant capacity, which could be one of the reasons for the reduced utilization of CGM by turbot.


Assuntos
Antioxidantes/metabolismo , Enterite/etiologia , Doenças dos Peixes/etiologia , Glutens/toxicidade , Zea mays/metabolismo , Fosfatase Ácida/metabolismo , Ração Animal/análise , Animais , Antioxidantes/química , Dieta , Enterite/imunologia , Enterite/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/metabolismo , Proteínas de Peixes/metabolismo , Linguados , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Superóxido Dismutase/metabolismo
14.
Bioprocess Biosyst Eng ; 38(5): 911-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25533040

RESUMO

UV photolysis was used to relieve inhibition of biomass growth by sulfadiazine (SD), a broad-spectrum anti-microbial. To investigate the effects of SD on biomass growth, three substrates-glucose alone (G), glucose plus sulfadiazine (G+SD), and glucose plus photolyzed SD (G+PSD)-were used to culture the bacteria acclimated to glucose. The biomass was strongly inhibited when SD was added into the glucose solution, but inhibition was relieved to a significant degree when the SD was treated with UV irradiation as a pretreatment. The biomass growth kinetics were described well by the Monod model when glucose was used as a substrate alone, but the kinetics followed a hybrid Aiba model for non-competitive inhibition when SD was added to the solution. When photolyzed SD was added to glucose solution to replace original SD, the growth still followed Aiba inhibition, but inhibition was significantly relieved: the maximum specific growth rate (µ max) increased by 17 %, and the Aiba inhibition concentration increased by 60 %. Aniline, a major product of UV photolysis, supported the growth of the glucose-biodegrading bacteria. Thus, UV photolysis of SD significantly relieved inhibition by lowering the SD concentration and by generating a biodegradable product.


Assuntos
Biomassa , Fotólise , Sulfadiazina/química , Compostos de Anilina/química , Anti-Infecciosos/química , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Glucose/química , Cinética , Esgotos , Raios Ultravioleta , Poluentes Químicos da Água/química , Purificação da Água
15.
Biodegradation ; 25(6): 911-21, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25199943

RESUMO

Sulfadiazine (SD), one of broad-spectrum antibiotics, exhibits limited biodegradation in wastewater treatment due to its chemical structure, which requires initial mono-oxygenation reactions to initiate its biodegradation. Intimately coupling UV photolysis with biodegradation, realized with the internal loop photobiodegradation reactor, accelerated SD biodegradation and mineralization by 35 and 71 %, respectively. The main organic products from photolysis were 2-aminopyrimidine (2-AP), p-aminobenzenesulfonic acid (ABS), and aniline (An), and an SD-photolysis pathway could be identified using C, N, and S balances. Adding An or ABS (but not 2-AP) into the SD solution during biodegradation experiments (no UV photolysis) gave SD removal and mineralization rates similar to intimately coupled photolysis and biodegradation. An SD biodegradation pathway, based on a diverse set of the experimental results, explains how the mineralization of ABS and An (but not 2-AP) provided internal electron carriers that accelerated the initial mono-oxygenation reactions of SD biodegradation. Thus, multiple lines of evidence support that the mechanism by which intimately coupled photolysis and biodegradation accelerated SD removal and mineralization was through producing co-substrates whose oxidation produced electron equivalents that stimulated the initial mono-oxygenation reactions for SD biodegradation.


Assuntos
Biodegradação Ambiental , Fotólise , Sulfadiazina/química , Sulfadiazina/metabolismo
16.
Arch Surg ; 137(6): 653-7; discussion 657-8, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12049535

RESUMO

HYPOTHESIS: Transarterial chemoembolization (TACE) is beneficial for selected patients with unresectable hepatocellular carcinoma (HCC). DESIGN AND SETTING: A prospective comparison study in a tertiary hospital. STUDY PERIOD: November 21, 1995, to May 2, 2001, with a mean follow-up of 939 days. PATIENTS: A total of 157 TACE treatments were performed in 88 patients with unresectable HCC: 132 treatments in 69 patients with focal HCC (F-HCC) and 25 treatments in 19 patients with diffuse HCC (D-HCC). INTERVENTIONS: Transarterial chemoembolization consisted of selective catheterization and intra-arterial infusion of a mixture of doxorubicin hydrochloride, cisplatin, and mitomycin followed by embolization. Sequential treatments were performed for bilobar HCC. MAIN OUTCOME MEASURES: Child-Pugh classification and clinical outcomes, including alpha-fetoprotein (AFP) response, length of hospital stay, readmission rate, and survival, were compared between patients with F-HCC and D-HCC following TACE using the chi(2) test, Fisher exact test, or t test (2-tailed, unpaired). RESULTS: Fifty-eight patients (84%) in the F-HCC group and 18 patients (95%) in the D-HCC group had cirrhosis. For those patients with cirrhosis, 58 (100%) in the F-HCC group and 14 (78%) in the D-HCC group had a Child-Pugh score of A or B (P =.002). The mean baseline AFP was higher in the D-HCC group: 55 577 vs 7815 ng/mL in the F-HCC group (P =.001). Of the patients secreting AFP, 4 (29%) of 14 in the D-HCC group and 30 (68%) of 44 in the F-HCC group had a significant decrease in AFP 1 month following TACE (P =.01). The mean hospital stay was longer (3 vs 1.9 days; P =.001), and readmissions occurred more frequently (44% vs 9%; P<.001) in the D-HCC group. The mean survival rate was significantly higher in the F-HCC group: 425 vs 103 days (P<.001). CONCLUSIONS: In patients with F-HCC, TACE is well tolerated and provides a survival benefit. However, there is no apparent benefit for patients with D-HCC. Importantly, tumor characteristics and hepatic reserve are essential criteria for successful TACE.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
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