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1.
J Emerg Med ; 64(1): 70-73, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36464549

RESUMO

BACKGROUND: Infected aortic aneurysm is a relatively rare disease with significant morbidity and mortality. Because of its deeper position, patients with infected aortic arch aneurysms may present with only fever and other vague symptoms, such as weakness, fatigue, dizziness, anorexia, and functional decline. It is difficult confirm a diagnosis that is based solely on history or physical examination, and it may only be apparent on imaging studies. CASE REPORT: We present a brief case report of a patient presenting to the emergency department with unexplained fever who was diagnosed with emphysematous salmonella-infected aneurysm of the aortic arch. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Infected aortic arch aneurysm is an extremely unusual disease entity that emergency physicians encounter. Because of the high mortality and morbidity of this catastrophic disease, an infected aortic aneurysm should be considered as a possible diagnosis in patients with persistent fever and vague symptoms without a specific infection focus. To avoid delayed diagnosis, emergency physicians should be aware of infected aortic arch aneurysm.


Assuntos
Aneurisma Infectado , Aneurisma da Aorta Torácica , Aneurisma Aórtico , Humanos , Salmonella
2.
J Therm Biol ; 94: 102761, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33293002

RESUMO

Cardiac arrest (CA) is a leading cause of mortality worldwide. Most of post-resuscitation related deaths are due to post-cardiac arrest syndrome (PCAS). After cardiopulmonary resuscitation (CPR), return of spontaneous circulation (ROSC) leads to renal ischemia-reperfusion injury, also known as PCAS. Many studies have focused on brain and heart injuries after ROSC, but renal failure has largely been ignored. Therefore, we investigated the protective effects of therapeutic hypothermia (TH) on asphyxial CA-induced renal injury in rats. Thirty rats were randomly divided into five groups: 1) the control group (sham); 2) the normothermic CA (nor.); 3) a normothermic CA group that received TH immediately within 2 h after CPR (Hypo. 2 hrs); 4) a normothermic CA group that received TH within 4 h after CPR (Hypo. 4 hrs); and 5) a normothermia CA group that received TH within 6 h after CPR (Hypo. 6 h). One day after CPR, all rats were sacrificed. Compared with the normothermic CA group, the TH groups demonstrated significantly increased survival rate (P < 0.05); decreased serum blood urea nitrogen, creatinine, and lactate dehydrogenase levels; and lower histological damage degree and malondialdehyde concentration in their renal tissue. Terminal deoxynucleotidyl transferase dUTP nick end labeling stain revealed that the number of apoptotic cells significantly decreased after 4 h and 6 h of TH compared to the results seen in the normothermic CA group. Moreover, TH downregulated the expression of cyclooxygenase-2 in the renal cortex compared to the normothermic CA group one day after CPR. These results suggest that TH exerts anti-apoptotic, anti-inflammatory, and anti-oxidative effects immediately after ROSC that protect against renal injury.


Assuntos
Parada Cardíaca/terapia , Hipotermia Induzida , Nefropatias/terapia , Animais , Asfixia/complicações , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Ciclo-Oxigenase 2/metabolismo , Parada Cardíaca/sangue , Parada Cardíaca/etiologia , Parada Cardíaca/metabolismo , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , L-Lactato Desidrogenase/sangue , Masculino , Malondialdeído/metabolismo , Ratos Sprague-Dawley
3.
Plant Cell Rep ; 38(11): 1403-1415, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31367772

RESUMO

KEY MESSAGE: IbSPF1, a novel target of IbMPK3/IbMPK6, regulates biotic stress response in sweetpotato. Environmental stresses due to biotic and abiotic factors negatively affect crop quality and productivity. To minimize the damage caused by these factors, numerous stress signaling pathways are activated in plants. Among these, the mitogen-activated protein kinase (MAPK) signaling cascade plays a pivotal role in diverse plant stress responses. MPK3 and MPK6 function in several cellular signaling pathways by phosphorylating downstream partner proteins in response to environmental stresses. However, little is known about the MPK3/MPK6 signaling pathway in sweetpotato [Ipomoea batatas (L.) Lam]. We recently confirmed that IbMPK3 and IbMPK6, two pathogen-responsive MAPKs, play essential roles in defense gene activation in sweetpotato. In this study, we show that sweetpotato SP8-binding factor (IbSPF1), a substrate of IbMPK3/IbMPK6, functions as a transcriptional regulator of biotic stress signaling in sweetpotato. IbSPF1 specifically interacts with IbMPK3 and IbMPK6, which phosphorylate Ser75 and Ser110 residues of IbSPF1. This increases the affinity of IbSPF1 for the W-box element in target gene promoters. Additionally, the expression of IbSPF1 was up-regulated under various stress conditions and different hormone treatments involved in plant defense responses. Interestingly, the phospho-mimicking mutant of IbSPF1 showed enhanced resistance to Pseudomonas syringae pv. tabaci, and transient expression of mutant IbSPF1 induced the expression of pathogenesis-related genes. These results indicate that the phosphorylation of IbSPF1 by IbMPK3/IbMPK6 plays a critical role in plant immunity by up-regulating the expression of downstream genes.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Ipomoea batatas/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/enzimologia , Fosforilação , Imunidade Vegetal , Proteínas de Plantas/química , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Pseudomonas syringae , Transdução de Sinais , Estresse Fisiológico/genética , Nicotiana/genética , Nicotiana/metabolismo , Fatores de Transcrição/genética
4.
Plant Cell Rep ; 38(11): 1393-1402, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31346717

RESUMO

KEY MESSAGE: IbOr-R96H resulted in carotenoid overaccumulation and enhanced abiotic stress tolerance in transgenic sweetpotato calli. The Orange (Or) protein is involved in the regulation of carotenoid accumulation and tolerance to various environmental stresses. Sweetpotato IbOr, with strong holdase chaperone activity, protects a key enzyme, phytoene synthase (PSY), in the carotenoid biosynthetic pathway and stabilizes a photosynthetic component, oxygen-evolving enhancer protein 2-1 (PsbP), under heat and oxidative stresses in plants. Previous studies of various plant species demonstrated that a single-nucleotide polymorphism (SNP) from Arg to His in Or protein promote a high level of carotenoid accumulation. Here, we showed that the substitution of a single amino acid at position 96 (Arg to His) of wild-type IbOr (referred to as IbOr-R96H) dramatically increases carotenoid accumulation. Sweetpotato calli overexpressing IbOr-WT or IbOr-Ins exhibited 1.8- or 4.3-fold higher carotenoid contents than those of the white-fleshed sweetpotato Yulmi (Ym) calli, and IbOr-R96H overexpression substantially increased carotenoid accumulation by up to 23-fold in sweetpotato calli. In particular, IbOr-R96H transgenic calli contained 88.4-fold higher levels of ß-carotene than those in Ym calli. Expression levels of carotenogenesis-related genes were significantly increased in IbOr-R96H transgenic calli. Interestingly, transgenic calli overexpressing IbOr-R96H showed increased tolerance to salt and heat stresses, with similar levels of malondialdehyde to those in calli expressing IbOr-WT or IbOr-Ins. These results suggested that IbOr-R96H is a useful target for the generation of efficient industrial plants, including sweetpotato, to cope with growing food demand and climate change by enabling sustainable agriculture on marginal lands.


Assuntos
Substituição de Aminoácidos/genética , Carotenoides/metabolismo , Ipomoea batatas/genética , Chaperonas Moleculares/genética , Proteínas de Plantas/genética , Resposta ao Choque Térmico , Ipomoea batatas/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal , Estresse Fisiológico , beta Caroteno/biossíntese , beta Caroteno/genética
5.
Am J Emerg Med ; 37(8): 1516-1526, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30466804

RESUMO

OBJECTIVE: To evaluate the prevalence of bacteremia and antimicrobial resistance, and associated factors among infectious patients transferred from long-term care hospitals (LTCHs). METHODS: Consecutive adult patients who were transferred for suspected infection from affiliated LTCH's to study hospital emergency department (ED) over a 12 month period from January to December 2016 were included retrospectively. Patients with positive blood cultures (excluding contaminants as clinically determined) were defined as primary measure and subjected to further analysis according to antimicrobial resistance pattern. The latter was categorized into 4 subgroups based on groups of antimicrobial choices for empiric choices of suspected bloodstream infections. R-Group 0: bacteria susceptible to penicillin and amoxicillin; R-Group 1: bacteria resistant to penicillin/amoxicillin, first, second, or third generation cephalosporins. R-Group 2: ESBL-producing bacteria or bacteria resistant methicillin, fourth generation cephalosporin, or fluoroquinolone. R-Group 3: highly resistant pathogens including vancomycin resistant enterococci, carbapenem or colistin resistant Gram negatives. Blood culture isolate could therefore be included in >1 group. RESULTS: Among 756 patients who were transferred from LTCHs, we excluded 278 patients who were not suspicious of infection and 65 patients who were not checked blood culture at ED. In total, 422 patients were enrolled. The incidence of bacteremia was 20.4% (n = 86). The most frequent pathogen was E. coli (n = 25) followed by S. aureus (n = 10), S. epidermidis (n = 8), and K. pneumonia (n = 6). The incidences of the R-Group 1, 2, and 3 groups were 16.8% (n = 71), 14.4% (n = 61), and 1.4% (n = 6), respectively. Of the Gram-positive pathogens (n = 44), the R-Group 1, 2, and 3 groups were 84.1% (n = 37), 75.0% (n = 33), and 9.1% (n = 4), respectively. Of the Gram-negative pathogens (n = 46), the R-Group 1, 2, and 3 groups were 82.6% (n = 38), 69.6% (n = 32), and 4.3% (n = 2), respectively. Among tested variables, initial serum procalcitonin level was significantly associated with the presence of bacteremia (AOR 1.03, 95% confidence interval 1.00-1.05), R-Group 1 (1.04, 1.01-1.07) and the R-Group 2 (1.04, 1.00-1.06). CONCLUSIONS: The prevalence of bloodstream infections in patients admitted from LTCH was high (20.4%) with majority of these infections from resistant bacteria. Procalcitonin levels were significantly higher in bacteremic patients with an increasing trend towards bacteria in the antimicrobial resistant groups.


Assuntos
Bacteriemia/epidemiologia , Bactérias/isolamento & purificação , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana , Transferência de Pacientes/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Hemocultura , Serviço Hospitalar de Emergência , Feminino , Humanos , Incidência , Assistência de Longa Duração , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Estudos Retrospectivos , Centros de Atenção Terciária , Adulto Jovem
6.
J Exp Bot ; 69(14): 3393-3400, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29385615

RESUMO

Carotenoids play essential roles in various light-harvesting processes in plants and help protect the photosynthetic machinery from photo-oxidative damage. Orange genes, which play a role in carotenoid accumulation, have recently been isolated from several plant species, and their functions have been intensively investigated. The Orange gene (IbOr) of sweet potato [Ipomoea batatas (L.) Lam] helps maintain carotenoid homeostasis to improve plant tolerance to environmental stress. IbOr, a protein with strong holdase chaperone activity, directly interacts with phytoene synthase, a key enzyme involved in carotenoid biosynthesis, in plants under stress conditions, resulting in increased carotenoid accumulation and abiotic stress tolerance. In addition, IbOr interacts with the oxygen-evolving enhancer protein 2-1, a member of a protein complex in photosystem II that is denatured under heat stress. Transgenic sweet potato plants overexpressing IbOr showed enhanced tolerance to high temperatures (47 °C). These findings indicate that IbOr protects plants from environmental stress not only by controlling carotenoid biosynthesis, but also by directly stabilizing photosystem II. In this review, we discuss the functions of IbOr and Or proteins in other plant species and their possible biotechnological applications for molecular breeding for sustainable development on marginal lands.


Assuntos
Carotenoides/fisiologia , Meio Ambiente , Ipomoea batatas/fisiologia , Proteínas de Plantas/fisiologia , Agricultura , Homeostase , Estresse Fisiológico
7.
BMC Plant Biol ; 17(1): 139, 2017 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-28806972

RESUMO

BACKGROUND: Sweetpotato (Ipomoea batatas [L.] Lam) is suitable for growth on marginal lands due to its abiotic stress tolerance. However, severe environmental conditions including low temperature pose a serious threat to the productivity and expanded cultivation of this crop. In this study, we aimed to develop sweetpotato plants with enhanced tolerance to temperature stress. RESULTS: P3 proteins are plant-specific ribosomal P-proteins that act as both protein and RNA chaperones to increase heat and cold stress tolerance in Arabidopsis. Here, we generated transgenic sweetpotato plants expressing the Arabidopsis ribosomal P3 (AtP3B) gene under the control of the CaMV 35S promoter (referred to as OP plants). Three OP lines (OP1, OP30, and OP32) were selected based on AtP3B transcript levels. The OP plants displayed greater heat tolerance and higher photosynthesis efficiency than wild type (WT) plants. The OP plants also exhibited enhanced low temperature tolerance, with higher photosynthesis efficiency and less membrane permeability than WT plants. In addition, OP plants had lower levels of hydrogen peroxide and higher activities of antioxidant enzymes such as peroxidase and catalase than WT plants under low temperature stress. The yields of tuberous roots and aerial parts of plants did not significantly differ between OP and WT plants under field cultivation. However, the tuberous roots of OP transgenic sweetpotato showed improved storage ability under low temperature conditions. CONCLUSIONS: The OP plants developed in this study exhibited increased tolerance to temperature stress and enhanced storage ability under low temperature compared to WT plants, suggesting that they could be used to enhance sustainable agriculture on marginal lands.


Assuntos
Aclimatação/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/fisiologia , Proteínas Ribossômicas/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Ipomoea batatas/genética , Ipomoea batatas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Proteínas Ribossômicas/metabolismo , Estresse Fisiológico/genética , Termotolerância/genética
8.
J Emerg Med ; 60(2): 245-247, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33059993

Assuntos
Face , Boca , Humanos , Masculino
11.
Appl Opt ; 52(4): 666-73, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23385904

RESUMO

A highly sensitive temperature sensor was made by use of a side-hole glass fiber filled with indium metal, and its optical properties were investigated. The temperature sensitivity of the fiber-optic temperature sensor was dλ/dT=-7.38 nm/K. The temperature sensitivity was also examined in sensors made by different lengths of the side-hole fiber and the indium-filled fiber region. The temperature sensitivity could be varied in the range of -1.83 to -7.38 nm/K by changing the relative length between the side-hole fiber and the indium-filled fiber region.

12.
ACS Omega ; 8(45): 42689-42698, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024713

RESUMO

Material-specific electrocatalytic activity and electrode design are essential factors in evaluating the performance of electrochemical sensors. Herein, the technique described involves electrospinning manganese-based metal-organic frameworks (Mn-MOFs) to develop MnOx nanostructures embedded in carbon nanofibers. The resulting structure features an electrocatalytic material for an enzyme-free glucose sensor. The elemental composition, morphology, and microstructure of the fabricated electrodes materials were characterized by using energy-dispersive X-ray spectroscopy (EDX), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Cyclic voltammetry (CV) and amperometric i-t (current-time) techniques are characteristically employed to assess the electrochemical performance of materials. The MOF MnOx-CNFs nanostructures significantly improve detection performance for nonenzymatic amperometric glucose sensors, including a broad linear range (0 mM to 9.1 mM), high sensitivity (4080.6 µA mM-1 cm-2), a low detection limit (0.3 µM, S/N = 3), acceptable selectivity, outstanding reproducibility, and stability. The strategy of metal and metal oxide-integrated CNF nanostructures based on MOFs opens interesting possibilities for the development of high-performance electrochemical sensors.

13.
ACS Biomater Sci Eng ; 9(2): 1002-1010, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36629494

RESUMO

Carbon dots (CDs) are considered a potential substance for use in biomarker applications due to their exceptional light stability. However, there are several unsolved uncertainties about CD toxicity in vitro and in vivo. In this study, a redesigned derivative of the natural polysaccharide inulin is connected with boron-doped amine-functionalized carbon dots (In@BN-CDs) through carbodiimide coupling to improve the biocompatibility of the nanoformulation. The toxicity and biodistribution of ln@BN-CDs in vivo and in vitro were explored in detail. The In@BN-CDs were tested after a single inhalation dosage of 10, 7, 5, 3, and 1 mg/kg. We explored a dose- and time-dependent technique of collecting blood samples and then centrifuged the blood samples and obtained serum samples, which were then analyzed for fluorescence inspection; findings showed that the fluorescence intensity decreased with time. Similarly, In@BN-CDs were effectively used as in vitro toxicity and fluorescent probes for cellular imaging in living cells due to their biocompatibility and cell membrane accessibility. The biocompatibility and efficacy of In@BN-CDs as fluorescent imaging agents have been demonstrated. The data suggest that the usage of In@BN-CDs in vitro and in vivo should be examined.


Assuntos
Boro , Inulina , Distribuição Tecidual , Carbono , Corantes Fluorescentes
14.
Opt Express ; 20(5): 5281-90, 2012 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-22418334

RESUMO

We propose a new dispersion control scheme by introducing hollow ring defects having a central air hole and a GeO2-or F-doped silica ring with in a square lattice photonic crystal fiber. We confirmed the flexible dispersion controllability in the proposed structure in two aspects of dispersion managements: ultra-flattened near-zero dispersion in the 530 nm-bandwidth over all communication bands and dispersion compensation in C, L, and U band with a high compensation ratio of 0.96~1.0 in reference to the standard single mode fiber. The proposed SLPCFs were also estimated to have an inherently low splice loss due to the index contrast between the doped-ring and silica that kept a good guidance even along with collapsed air holes, which cannot be achieved in conventional PCFs.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Dióxido de Silício/química , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Fótons , Espalhamento de Radiação
15.
Opt Express ; 20(2): 1385-91, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22274483

RESUMO

We propose a novel design of photonic crystal fiber (PCF) using an elliptical air hole in the core as a defected core in order to enhance the performance of modal birefringence and to control the properties of chromatic dispersion at the same time. From the simulation results, it is shown that the proposed fiber has high birefringence up to the order of 10(-2), negative flattened chromatic dispersion in a broad range of wavelengths, and low confinement loss less than that of the single mode fiber. The outstanding advantage of the proposed PCF is that high birefringence, negative flattened dispersion, and low confinement loss can be achieved just by adding a small sized elliptical air hole in the core to the elliptical air hole PCF, especially at the same time.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Fibras Ópticas , Birrefringência , Simulação por Computador , Cristalização , Desenho de Equipamento
16.
Medicine (Baltimore) ; 101(28): e29355, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35839015

RESUMO

RATIONALE: Sodium nitrite is a potent oxidizing agent that impairs oxygen transport and delivery through methemoglobin formation. Clinical manifestations are known to induce methemoglobinemia, dysrhythmia, hypotension, and even death. While accidental intoxication of sodium nitrite by contaminated water and food has previously occurred, there has been a substantial upsurge in suicide intoxication in recent years. PATIENT CONCERNS: We present case reports of 2 patients who attempted suicide by sodium nitrite after ordering a "suicide powder" on the internet market. They were brought to the emergency department after attempting suicide by ingesting sodium nitrite. They experienced dyspnea, cyanosis, and mild nausea. DIAGNOSIS: Based on their history and blood tests, methemoglobinemia was initially diagnosed. INTERVENTIONS AND OUTCOMES: The patients received methylene blue antidotal therapy in the emergency department. The patients were discharged after neuropsychiatric evaluation and treatment for mental illness, suicidal ideation, and suicide attempts. They informed us of how simple and easy it was for them to buy sodium nitrite for suicidal purposes. LESSONS: With widely shared information on the usage of sodium nitrite for suicide and the absence of proper regulation, the incidence of acute poisoning will increase. This increases physicians' chances of encountering unexplained cyanosis and methemoglobinemia. Clinical suspicion of sodium nitrite intoxication is warranted in cases of unexplained cyanosis or methemoglobinemia. We want to highlight how simple and easy it is to buy sodium nitrite for suicidal purposes.


Assuntos
Metemoglobinemia , Nitrito de Sódio , Cianose/complicações , Humanos , Internet , Metemoglobinemia/induzido quimicamente , Metemoglobinemia/diagnóstico , Metemoglobinemia/tratamento farmacológico , Azul de Metileno/uso terapêutico , Tentativa de Suicídio
17.
Emerg Med Int ; 2022: 7994866, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669167

RESUMO

Introduction: This study aimed to establish a predictive model that includes physiological parameters and identify independent risk factors for severe injuries in bicycle rider accidents. Methods: This was a multicenter observational study. For four years, we included patients with bicycle rider injuries in the Emergency Department-Based Injury In-depth Surveillance database. In this study, we regarded ICD admission or in-hospital mortality as parameters of severe trauma. Univariate and multivariate logistic regression analyses were performed to assess risk factors for severe trauma. A receiver operating characteristic (ROC) curve was generated to evaluate the performance of the regression model. Results: This study included 19,842 patients, of whom 1,202 (6.05%) had severe trauma. In multivariate regression analysis, male sex, older age, alcohol use, motor vehicle opponent, load state (general and crosswalk), blood pressure, heart rate, respiratory rate, and Glasgow Coma Scale were the independent factors for predicting severe trauma. In the ROC analysis, the area under the ROC curve for predicting severe trauma was 0.848 (95% confidence interval: 0.830-0.867). Conclusion: We identified independent risk factors for severe trauma in bicycle rider accidents and believe that physiologic parameters contribute to enhancing prediction ability.

18.
Mol Med Rep ; 25(1)2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34796906

RESUMO

Although multi­organ dysfunction is associated with the survival rate following cardiac arrest (CA), the majority of studies to date have focused on hearts and brains, and few studies have considered renal failure. The objective of the present study, therefore, was to examine the effects of therapeutic hypothermia on the survival rate, pathophysiology and antioxidant enzymes in rat kidneys following asphyxial CA. Rats were sacrificed one day following CA. The survival rate, which was estimated using Kaplan­Meier analysis, was 42.9% one day following CA. However, hypothermia, which was induced following CA, significantly increased the survival rate (71.4%). In normothermia rats with CA, the serum blood urea nitrogen level was significantly increased one day post­CA. In addition, the serum creatinine level was significantly increased one day post­CA. However, in CA rats exposed to hypothermia, the levels of urea nitrogen and creatinine significantly decreased following CA. Histochemical staining revealed a significant temporal increase in renal injury after the normothermia group was subjected to CA. However, renal injury was significantly decreased in the hypothermia group. Immunohistochemical analysis of the kidney revealed a significant decrease in antioxidant enzymes (copper­zinc superoxide dismutase, manganese superoxide dismutase, glutathione peroxidase and catalase) with time in the normothermia group. However, in the hypothermia group, these enzymes were significantly elevated following CA. Collectively, the results revealed that renal dysfunction following asphyxial CA was strongly associated with the early survival rate and therapeutic hypothermia reduced renal injury via effective antioxidant mechanisms.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Antioxidantes/farmacologia , Asfixia/complicações , Asfixia/terapia , Parada Cardíaca/terapia , Hipotermia Induzida/métodos , Rim/efeitos dos fármacos , Rim/lesões , Injúria Renal Aguda/genética , Injúria Renal Aguda/patologia , Animais , Nitrogênio da Ureia Sanguínea , Encéfalo/fisiopatologia , Creatinina , Modelos Animais de Doenças , Coração/fisiopatologia , Hipotermia , Rim/patologia , Rim/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Taxa de Sobrevida
19.
Antioxidants (Basel) ; 10(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406723

RESUMO

Carotenoids function as photosynthetic accessory pigments, antioxidants, and vitamin A precursors. We recently showed that transgenic sweetpotato calli overexpressing the mutant sweetpotato (Ipomoea batatas [L.] Lam) Orange gene (IbOr-R96H), which carries a single nucleotide polymorphism responsible for Arg to His substitution at amino acid position 96, exhibited dramatically higher carotenoid content and abiotic stress tolerance than calli overexpressing the wild-type IbOr gene (IbOr-WT). In this study, we generated transgenic sweetpotato plants overexpressing IbOr-R96H under the control of the cauliflower mosaic virus (CaMV) 35S promoter via Agrobacterium-mediated transformation. The total carotenoid contents of IbOr-R96H storage roots (light-orange flesh) and IbOr-WT storage roots (light-yellow flesh) were 5.4-19.6 and 3.2-fold higher, respectively, than those of non-transgenic (NT) storage roots (white flesh). The ß-carotene content of IbOr-R96H storage roots was up to 186.2-fold higher than that of NT storage roots. In addition, IbOr-R96H plants showed greater tolerance to heat stress (47 °C) than NT and IbOr-WT plants, possibly because of higher DPPH radical scavenging activity and ABA contents. These results indicate that IbOr-R96H is a promising strategy for developing new sweetpotato cultivars with improved carotenoid contents and heat stress tolerance.

20.
Plant Physiol Biochem ; 166: 549-557, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34174660

RESUMO

Lignin is associated with cell wall rigidity, water and solute transport, and resistance to diverse stresses in plants. Lignin consists of polymerized monolignols (p-coumaryl, coniferyl, and sinapyl alcohols), which are synthesized by cinnamyl alcohol dehydrogenase (CAD) in the phenylpropanoid pathway. We previously investigated cold-induced IbCAD1 expression by transcriptome profiling of cold-stored tuberous roots of sweetpotato (Ipomoea batatas [L.] Lam). In this study, we confirmed that IbCAD1 expression levels depended on the sweetpotato root type and were strongly induced by several abiotic stresses. We generated transgenic sweetpotato plants overexpressing IbCAD1 (TC plants) to investigate CAD1 physiological functions in sweetpotato. TC plants displayed lower root weights and lower ratios of tuberous roots to pencil roots than non-transgenic (NT) plants. The lignin contents in tuberous roots of NT and TC plants differed slightly, but these differences were not significant. By contrast, monolignol levels and syringyl (S)/guaiacyl (G) ratios were higher in TC plants than NT plants, primarily owing to syringyl unit accumulation. Tuberous roots of TC plants displayed enhanced low-temperature (4 °C) storage with lower malondialdehyde and H2O2 contents than NT plants. We propose that high monolignol levels in TC tuberous roots served as substrates for increased peroxidase activity, thereby enhancing antioxidation capacity against cold stress-induced reactive oxygen species. Increased monolignol contents and/or increased S/G ratios might contribute to pathogen-induced stress tolerance as a secondary chilling-damage response in sweetpotato. These results provide novel information about CAD1 function in cold stress tolerance and root formation mechanisms in sweetpotato.


Assuntos
Ipomoea batatas , Resposta ao Choque Frio , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio , Ipomoea batatas/genética , Fenótipo , Plantas Geneticamente Modificadas , Temperatura
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