Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 225
Filtrar
1.
Cell Mol Life Sci ; 80(11): 337, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37897551

RESUMEN

Hypervirulent Klebsiella pneumoniae (hvKP) is a highly lethal opportunistic pathogen that elicits more severe inflammatory responses compared to classical Klebsiella pneumoniae (cKP). In this study, we investigated the interaction between hvKP infection and the anti-inflammatory immune response gene 1 (IRG1)-itaconate axis. Firstly, we demonstrated the activation of the IRG1-itaconate axis induced by hvKP, with a dependency on SYK signaling rather than STING. Importantly, we discovered that exogenous supplementation of itaconate effectively inhibited excessive inflammation by directly inhibiting SYK kinase at the 593 site through alkylation. Furthermore, our study revealed that itaconate effectively suppressed the classical activation phenotype (M1 phenotype) and macrophage cell death induced by hvKP. In vivo experiments demonstrated that itaconate administration mitigated hvKP-induced disturbances in intestinal immunopathology and homeostasis, including the restoration of intestinal barrier integrity and alleviation of dysbiosis in the gut microbiota, ultimately preventing fatal injury. Overall, our study expands the current understanding of the IRG1-itaconate axis in hvKP infection, providing a promising foundation for the development of innovative therapeutic strategies utilizing itaconate for the treatment of hvKP infections.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Disbiosis/tratamiento farmacológico , Infecciones por Klebsiella/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Alquilación , Quinasa Syk
2.
Ann Surg ; 278(5): e988-e994, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37309899

RESUMEN

OBJECTIVES: We aimed to determine the current incidence rate and risk factors for surgical site infection (SSI) after abdominal surgery in China and to further demonstrate the clinical features of patients with SSI. BACKGROUND: Contemporary epidemiology and clinical features of SSI after abdominal surgery remain poorly characterized. METHODS: A prospective multicenter cohort study was conducted from March 2021 to February 2022; the study included patients who underwent abdominal surgery at 42 hospitals in China. Multivariable logistic regression analysis was performed to identify risk factors for SSI. Latent class analysis (LCA) was used to explore the population characteristics of SSI. RESULTS: In total, 23,982 patients were included in the study, of whom 1.8% developed SSI. There was a higher SSI incidence in open surgery (5.0%) than in laparoscopic or robotic surgeries (0.9%). Multivariable logistic regression indicated that the independent risk factors for SSI after abdominal surgery were older age, chronic liver disease, mechanical bowel preparation, oral antibiotic bowel preparation, colon or pancreas surgery, contaminated or dirty wounds, open surgery, and colostomy/ileostomy. LCA revealed 4 subphenotypes in patients undergoing abdominal surgery. Types α and ß were mild subclasses with a lower SSI incidence; whereas types γ and δ were the critical subgroups with a higher SSI incidence, but their clinical features were different. CONCLUSIONS: LCA identified 4 subphenotypes in patients who underwent abdominal surgery. Types γ and δ were critical subgroups with a higher SSI incidence. This phenotype classification can be used to predict SSI after abdominal surgery.


Asunto(s)
Laparoscopía , Infección de la Herida Quirúrgica , Humanos , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Estudios Prospectivos , Estudios de Cohortes , Laparoscopía/efectos adversos , Factores de Riesgo , Incidencia
3.
Neuroimmunomodulation ; 29(4): 317-326, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34942622

RESUMEN

BACKGROUND: Elevation of AMP-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) signaling can suppress intracerebral hemorrhage (ICH)-induced neurological impairments. As an isoquinoline alkaloid, Berberine exerts neuroprotective effects in neurological disease models with activated AMPK/PGC1α signaling. AIM: We aim to study the effect of Berberine on ICH-induced brain injury and explore the potential molecular mechanism. METHODS: ICH model was established in mice through intracerebral injection of autologous whole blood, followed by treatment with Berberine. Neurological impairments were assessed by the modified neurological severity score and behavioral assays. Brain edema and blood-brain barrier (BBB) integrity were assessed by water content in the brain, amount of extravasated Evans blue, and BBB tight junction components. Neuroinflammatory responses were assessed by inflammatory cytokine levels. AMPK/PGC1α signaling was examined by AMPK mRNA expression and phosphorylated AMPK and PGC1α protein levels. RESULTS: Berberine (200 mg/kg) attenuated ICH-induced neurological deficits, motor and cognitive impairment, and BBB disruption. Berberine also suppressed ICH-induced inflammatory responses indicated by reduced production of inflammatory cytokines. Finally, Berberine drastically elevated AMPK/PGC1α signaling in the hemisphere of ICH mice. CONCLUSION: Our findings suggest that Berberine plays an important neuroprotective role against ICH-induced neurological impairments and BBB injury, probably by inhibition of inflammation and activation of AMPK/PGC1α signaling.


Asunto(s)
Berberina , Barrera Hematoencefálica , Animales , Ratones , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/farmacología , Berberina/farmacología , Berberina/uso terapéutico , Berberina/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/farmacología , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/tratamiento farmacológico , Hemorragia Cerebral/metabolismo , Modelos Animales de Enfermedad , Citocinas/metabolismo , Inflamación/metabolismo
4.
Bioorg Med Chem ; 69: 116916, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35792403

RESUMEN

Microglia-induced neuroinflammation plays a critical role in neurological diseases. At present, RIPK2 is considered to participate in inflammatory and autoimmune cellular pathways and diseases. RIPK2 is found to be a pivotal therapeutic target in neurologic disorders related to inflammation. In our research, we discovered the protective function of tunicatachalcone (TC) against neuroinflammation. TC is a natural chalcone compound derived from Pongamia pinnata, a medicinal plant. The results revealed that TC (5-20 µM) ameliorated the activation of BV-2 microglia induced by lipopolysaccharide (LPS) in a dose-dependent way, which was proved by the reduced production of inflammation-related mediators. By using SPR-LC-MS/MS analysis, we revealed the potent inhibitory function of TC against neuroinflammation mediated by microglia via targeting RIPK2. A strong binding between TC and RIPK2 was further demonstrated based on the results of SPR, MST and molecular modeling. Through applying mRNA transcriptomics and bioinformatics analysis, it was demonstrated that TC could mediate RIPK2-dependent gene transcription to exert the neuroprotective effect. In summary, our research presented that RIPK2 was a possible therapeutic target of TC.


Asunto(s)
Productos Biológicos , Microglía , Productos Biológicos/farmacología , Cromatografía Liquida , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/farmacología , Enfermedades Neuroinflamatorias , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor/metabolismo , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor/farmacología , Espectrometría de Masas en Tándem
5.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36430765

RESUMEN

CCCH zinc finger proteins contain one to six tandem CCCH motifs composed of three cysteine and one histidine residues and have been widely found in eukaryotes. Plant CCCH proteins control a wide range of developmental and adaptive processes through DNA-protein, RNA-protein and/or protein-protein interactions. The complex networks underlying these processes regulated by plant CCCH proteins are often involved in phytohormones as signal molecules. In this review, we described the evolution of CCCH proteins from green algae to vascular plants and summarized the functions of plant CCCH proteins that are influenced by six major hormones, including abscisic acid, gibberellic acid, brassinosteroid, jasmonate, ethylene and auxin. We further compared the regulatory mechanisms of plant and animal CCCH proteins via hormone signaling. Among them, Arabidopsis AtC3H14, 15 and human hTTP, three typical CCCH proteins, are able to integrate multiple hormones to participate in various biological processes.


Asunto(s)
Arabidopsis , Regulación de la Expresión Génica de las Plantas , Humanos , Dedos de Zinc , Filogenia , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Hormonas/metabolismo
6.
Eur J Immunol ; 50(3): 464-467, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31756255

RESUMEN

Pyroptosis is a type of programmed lytic cell death that could be activated by either the canonical or noncanonical inflammasome pathway. In this study, we aimed to examine the effect of hypertonic solution on noncanonical pyroptosis in macrophage. We found that although hypertonic solution had a general inhibitory effect on noncanonical pyroptosis, the underlying mechanism varied by the solute causing hypertonicity. Specifically, hypertonic NaCl or KCl solution inhibited the cleavage of gasdermin D, the pore-forming protein in pyroptosis, whereas hypertonic saccharide solution did not affect the cleavage or membrane binding of gasdermin D. In this case, nevertheless, pyroptosis was still inhibited as evidenced by the preserved mitochondria activity and cell membrane permeability.


Asunto(s)
Soluciones Hipertónicas/química , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/metabolismo , Proteínas de Unión a Fosfato/metabolismo , Piroptosis/fisiología , Animales , Ratones
7.
Ecotoxicol Environ Saf ; 224: 112685, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34425537

RESUMEN

Polyaspartic acid (PASP) is a macromolecule compound with carboxylic acid side chains which is polymerized by L-aspartic acid, has been used as a biodegradable and environmentally-friendly chelating agent to enhance the phytoremediation of heavy metal-contaminated soils. Cadmium (Cd) is a toxic element for plant growth, productivity, and food security. To reveal the responses of PASP to plant physiology and morphology under Cd stress, we comprehensively analyzed soil characteristics, cell ultrastructure, reactive oxygen species (ROS), antioxidant enzymes, Cd uptake, transport, subcellular distribution, cell wall compositions, and their Cd chelating capacity in rapeseed. The results showed PASP increased the content of total N, total P, and available P in soil by 3.4%, 28.6%, and 39.8%, respectively, but did not change soil pH and available Cd. Meanwhile, PASP promoted dry mass accumulation and increased photosynthetic pigment content in rapeseed leaves by maintaining the chloroplast structure. Lower malondialdehyde (MDA) content and hydrogen peroxide (H2O2) accumulation and activated antioxidant enzymes in leaves indicate that PASP contributed to relieving Cd-induced oxidative damage to cells of rapeseed leaves. The results indicated that PASP application increased the Cd distribution ratio in root cell walls from 47.4% to 62.3% and decreased the Cd content in xylem sap by 37.8%, which ultimately reduced Cd reallocation in leaves. Additionally, higher pectin content and Cd in pectin resulted in higher Cd retention in leaf cell walls while reducing its concentration in the organelle fraction. The results indicated that 0.3% PASP effectively alleviated Cd stress in rapeseed leaves by inhibiting Cd transportation from roots, activating antioxidant enzymes to scavenge ROS, and promoting Cd chelation by cell wall pectin in leaves.

8.
Clin Infect Dis ; 71(Suppl 4): S337-S362, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33367581

RESUMEN

The Chinese guidelines for IAI presented here were developed by a panel that included experts from the fields of surgery, critical care, microbiology, infection control, pharmacology, and evidence-based medicine. All questions were structured in population, intervention, comparison, and outcomes format, and evidence profiles were generated. Recommendations were generated following the principles of the Grading of Recommendations Assessment, Development, and Evaluation system or Best Practice Statement (BPS), when applicable. The final guidelines include 45 graded recommendations and 17 BPSs, including the classification of disease severity, diagnosis, source control, antimicrobial therapy, microbiologic evaluation, nutritional therapy, other supportive therapies, diagnosis and management of specific IAIs, and recognition and management of source control failure. Recommendations on fluid resuscitation and organ support therapy could not be formulated and thus were not included. Accordingly, additional high-quality clinical studies should be performed in the future to address the clinicians' concerns.


Asunto(s)
Fístula , Infecciones Intraabdominales , Cirujanos , China , Cuidados Críticos , Humanos , Infecciones Intraabdominales/diagnóstico , Infecciones Intraabdominales/tratamiento farmacológico
9.
BMC Infect Dis ; 20(1): 837, 2020 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-33183253

RESUMEN

PURPOSES: Surgical site infection (SSI) after colorectal surgery is a frequent complication associated with the increase in morbidity, medical expenses, and mortality. To date, there is no nationwide large-scale database of SSI after colorectal surgery in China. The aim of this study was to determine the incidence of SSI after colorectal surgery in China and to further evaluate the related risk factors. METHODS: Two multicenter, prospective, cross-sectional studies covering 55 hospitals in China and enrolling adult patients undergoing colorectal surgery were conducted from May 1 to June 30 of 2018 and the same time of 2019. The demographic and perioperative characteristics were collected, and the main outcome was SSI within postoperative 30 days. Multivariable logistic regressions were conducted to predict risk factors of SSI after colorectal surgery. RESULTS: In total, 1046 patients were enrolled and SSI occurred in 74 patients (7.1%). In the multivariate analysis with adjustments, significant factors associated with SSI were the prior diagnosis of hypertension (OR, 1.903; 95% confidence interval [CI], 1.088-3.327, P = 0.025), national nosocomial infection surveillance risk index score of 2 or 3 (OR, 3.840; 95% CI, 1.926-7.658, P < 0.001), laparoscopic or robotic surgery (OR, 0.363; 95% CI, 0.200-0.659, P < 0.001), and adhesive incise drapes (OR, 0.400; 95% CI, 0.187-0.855, P = 0.018). In addition, SSI group had remarkably increased length of postoperative stays (median, 15.0 d versus 9.0d, P < 0.001), medical expenses (median, 74,620 yuan versus 57,827 yuan, P < 0.001), and the mortality (4.1% versus 0.3%, P = 0.006), compared with those of non-SSI group. CONCLUSION: This study provides the newest data of SSI after colorectal surgery in China and finds some predictors of SSI. The data presented in our study can be a tool to develop optimal preventive measures and improve surgical quality in China.


Asunto(s)
Cirugía Colorrectal/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Anciano , China/epidemiología , Infección Hospitalaria/epidemiología , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
10.
Chin J Traumatol ; 23(6): 311-313, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32863153

RESUMEN

Intra-abdominal infection (IAI) is a deadly condition in which the outcome is associated with urgent diagnosis, assessment and management, including fluid resuscitation, antibiotic administration while obtaining further laboratory results, attaining precise measurements of hemodynamic status, and pursuing source control. This last item makes abdominal sepsis a unique treatment challenge. Delayed or inadequate source control is an independent predictor of poor outcomes and recognizing source control failure is often difficult or impossible. Further complicating issue in the debate is surrounding the timing, adequacy, and procedures of source control. This review evaluated and summarized the current approach and challenges in IAI management, which are the future research directions.


Asunto(s)
Infecciones Intraabdominales/diagnóstico , Infecciones Intraabdominales/terapia , Antibacterianos/administración & dosificación , Drenaje , Fluidoterapia , Hemodinámica , Humanos , Infecciones Intraabdominales/fisiopatología , Laparoscopía , Laparotomía , Pronóstico , Sepsis
11.
BMC Infect Dis ; 19(1): 597, 2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31288746

RESUMEN

BACKGROUND: Necrotizing soft tissue infections (NSTIs) is severe surgical infections which can occur following trauma or abdominal surgery. NSTIs secondary to gastrointestinal (GI) fistula is a rare but severe complication. METHODS: A retrospective cohort study was performed on all subjects presenting with GI fistulas associated NSTIs were included. Clinical characteristics, microbiological profile, operations performed, and outcomes of patients were analyzed. RESULTS: Between 2014 and 2017, 39 patients were finally enrolled. The mean age were 46.9 years and male were the dominant. For the etiology of fistula, 25 (64.1%) of the patients was due to trauma. Overall, in-hospital death occurred in 15 (38.5%) patients. Microbiologic findings were obtained from 31 patients and Klebsiella pneumoniae was the most common species (41.0%). Eight patients were treated with an open abdomen; negative pressure wound therapy was used in 33 patients and only 2 patients received hyperbaric oxygen therapy. Younger age and delayed abdominal wall reconstruction repair were more common in trauma than in non-trauma. Non-survivors had higher APACHE II score, less source control< 48 h and lower platelet count on admission than survivors. Multiple organ dysfunction syndrome, multidrug-resistant organisms and source control failure were the main cause of in-hospital mortality. CONCLUSIONS: Trauma is the main cause of GI fistulas associated NSTIs. Sepsis continues to be the most important factor related to mortality. Our data may assist providing enlightenment for quality improvement in these special populations.


Asunto(s)
Fístula del Sistema Digestivo/diagnóstico , Infecciones de los Tejidos Blandos/diagnóstico , Adulto , Anciano , Fístula del Sistema Digestivo/etiología , Fístula del Sistema Digestivo/microbiología , Fístula del Sistema Digestivo/terapia , Femenino , Mortalidad Hospitalaria , Humanos , Oxigenoterapia Hiperbárica , Unidades de Cuidados Intensivos , Klebsiella pneumoniae/aislamiento & purificación , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones de los Tejidos Blandos/complicaciones , Infecciones de los Tejidos Blandos/microbiología , Infecciones de los Tejidos Blandos/terapia , Staphylococcus aureus/aislamiento & purificación , Resultado del Tratamiento
12.
J Mater Sci Mater Med ; 30(9): 109, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31535210

RESUMEN

Treatment of an open abdomen (OA) wound combined with an intestinal fistula is a challenge in the clinic. Here, inspired by the antibacterial activity of graphene (G) and its derivatives, we present a hybrid patch based on the ability of graphene and polycaprolactone (PCL) to kill bacteria and save the cells in a wound. Benefiting from the antibacterial ability of graphene oxide (GO), cells could survive in the presence of bacteria. With the increased ability to protect cells, this patch accelerated wound healing in an OA and intestinal fistula wound model. Additionally, the sub-acute toxicity score showed no extra damage to organs. In conclusion, the employment of the hybrid material for an OA and an intestinal fistula wound healing is encouraging. A hybrid patch based on graphene oxide and polycaprolactone electrospun was generated for open abdomen and fistula wound. The application of the hybrid patch could save the cells from bacteria which contribute to accelerating wound healing.


Asunto(s)
Grafito/química , Grafito/farmacología , Fístula Intestinal/prevención & control , Técnicas de Abdomen Abierto/instrumentación , Mallas Quirúrgicas , Cicatrización de Heridas/fisiología , Animales , Antibacterianos/química , Antibacterianos/farmacología , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Humanos , Masculino , Ensayo de Materiales , Nanofibras/química , Técnicas de Abdomen Abierto/métodos , Ratas , Ratas Sprague-Dawley , Cicatrización de Heridas/efectos de los fármacos
13.
Ecotoxicol Environ Saf ; 182: 109451, 2019 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-31352213

RESUMEN

Potassium (K) is an essential macronutrient for plant growth and development. However, in China, available K is relatively low in the soil, and with the extensive use of chemical fertilizer, K use efficiency is constantly reducing, and consequently increasing the potential risk of environmental pollution and economic loss. Therefore, it is essential to reduce the negative impact of over-fertilization on the environment to obtain optimal crop yield. Biochar as a soil amendment has been applied to improve soil fertility and increase crop yield. However, the effects of successive biochar application on cotton yield, agronomy efficiencies and potash fertilizer reduction are not well documented. Our results of a pot experiment showed that the application of 1% biochar to soil under different K levels significantly improved dry mass accumulation and K content of different plant parts, and increased the number of buds, bolls and effective branches of cotton. Particularly, plants treated with 150 mg/kg K2O and 1% biochar had the highest growth parameters. The most important characteristics including the harvest index, K fertilizer contribution index, partial factor productivity, agronomic efficiency and apparent recovery efficiency of K under C1 (1% biochar) were generally greater than those under C0 (without biochar). The 75 mg/kg K2O application was optimal to produce the highest yield with 1% biochar, demonstrating that biochar can increase cotton yield and therefore, reduces chemical K fertilizer application and alleviates agricultural environment risks of chemical fertilizer.


Asunto(s)
Carbón Orgánico/química , Producción de Cultivos/métodos , Fertilizantes/análisis , Gossypium/crecimiento & desarrollo , Potasio/análisis , Suelo/química , China , Minerales
14.
J Environ Manage ; 246: 426-433, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31200177

RESUMEN

The distribution of boron (B) in leaves is far from uniform, and tolerance to B toxicity should be varied in different portions of an entire leaf. Here, according to the order and degree of leaf chlorosis, a whole leaf blade of trifoliate orange [Poncirus trifoliata (L.) Raf.] rootstock was divided into two segments-leaf tip and leaf center, and transmission electron microscope (TEM) and fourier transform infrared spectroscopy (FTIR) were used to obtain more detailed information on the cell ultrastructure and component architecture of the two leaf segments under B toxicity. Results revealed that B toxicity led to alterations in pectin network crosslinking structure of leaf tip and destruction of cell wall integrity. Moreover, B toxicity altered protein structure and decreased protein content, while increased carbohydrate content in the two leaf segments, especially in leaf tip. Excess B supply reduced the cellulose content in leaf tip but increased in leaf center. TEM micrographs exhibited chloroplast disintegration and plastoglobulus accumulation in cells of two different leaf sections of B-toxicity plants, with less pronounced changes in leaf center. Furthermore, B toxicity only induced accumulation of starch grains in cells of leaf center. Overall results indicated that the B-toxic-induced biochemical changes of the cell ultrastructure and component architecture greatly differed in leaf tip and center. This study facilitates a better understanding of structural changes in different leaf portions of P. trifoliata under B toxicity stress and provides new ideas for further research on other elements in different plant leaf portions.


Asunto(s)
Citrus , Poncirus , Boro , Hojas de la Planta , Raíces de Plantas
15.
Artículo en Inglés | MEDLINE | ID: mdl-30199329

RESUMEN

Aluminum (Al) toxicity is a major factor limiting plant productivity. The objective of the present study was to develop the mechanisms of boron (B) alleviating aluminum toxicity in citrus. The results showed that aluminum toxicity severely hampered root elongation. Interestingly, under aluminum exposure, boron supply improved superoxide dismutase activity while reducing peroxidase, catalase and polyphenol oxidase activities. Likewise, the contents of H2O2, lipid peroxidation, protein and proline in roots were markedly decreased by boron application under aluminum exposure. Our results demonstrated that boron could alleviate aluminum toxicity by regulating antioxidant enzyme activities in the roots.


Asunto(s)
Aluminio/toxicidad , Antioxidantes/metabolismo , Boro/metabolismo , Citrus/fisiología , Contaminantes del Suelo/toxicidad , Catalasa/metabolismo , Catecol Oxidasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Peroxidasa/metabolismo
16.
Eur J Clin Microbiol Infect Dis ; 37(4): 679-689, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29238932

RESUMEN

The prevalence of hypervirulent Klebsiella pneumoniae (hvKP) is high in China, but clinical characteristics and outcomes of hvKP induced bloodstream infections (BSIs) are not clear. The purpose of the present study was to determine the risk factors and clinical outcomes of hvKP-BSIs in populations admitted in a teaching hospital of Nanjing, China. The genetic characteristics and antibiotic resistance patterns of the hvKP strains were further analyzed. A retrospective study was conducted in 143 patients with K. pneumoniae BSIs at Jinling Hospital in China from September 2015 to December 2016. A positive polymerase chain reaction (PCR) amplification of the plasmid-borne rmpA (p-rmpA) and aerobactin (iucA) was identified as hvKP. Overall, 24.5% (35/143) of K. pneumoniae isolates were hvKP. Multivariate analysis implicated diabetes mellitus (OR = 3.356) and community-acquired BSIs (OR = 4.898) as independent risk factors for hvKP-BSIs. The 30-day mortality rate of the hvKP-BSIs group was 37.1% (13/35) compared with 40.7% (44/108) in the cKP-BSIs control group (P = 0.706). The KPC-producing isolates (OR = 2.851), underlying disease with gastrointestinal fistula (OR = 3.054), APACHE II score ≥ 15 (OR = 6.694) and Pitt bacteremia score ≥ 2 (OR = 6.232) at infection onset were independent predictors for 30-day mortality of K. pneumoniae bacteremia patients. A high percentage (57.1%, 20/35) of KPC-producing isolates was observed among hvKP strains and ST11 was dominant in hvKP strains (17/35, 48.6%). KPC-producing hvKP is emerging, indicating the importance of epidemiologic surveillance and clinical awareness of this pathogen.


Asunto(s)
Bacteriemia , Farmacorresistencia Bacteriana , Infecciones por Klebsiella , Klebsiella pneumoniae , Adulto , Anciano , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/epidemiología , Bacteriemia/microbiología , Bacteriemia/mortalidad , China/epidemiología , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/mortalidad , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/mortalidad , Femenino , Hospitales de Enseñanza , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/mortalidad , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/patogenicidad , Masculino , Persona de Mediana Edad , Tipificación Molecular , Análisis Multivariante , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Virulencia
17.
Ecotoxicol Environ Saf ; 165: 202-210, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30196002

RESUMEN

Aluminum toxicity limits the plant growth by inducing inhibition of root elongation. Although several mechanisms have been proposed regarding the phytotoxic effects of aluminum on inhibition of root elongation; the primary causes of aluminum induced root inhibition and its mitigation by boron (B) are still elusive. The present study was carried out to explore the mechanisms of B induced mitigation of aluminum toxicity and to investigate the changes in well wall structure under aluminum toxicity coupled with the techniques of confocal laser microscope, lumogallion and transmission electron microscope. The results revealed that aluminum toxicity severely hampered the root elongation and plant biomass. Moreover, alteration in subcellular structure were observed under aluminum toxicity, however, such negative effects were further exacerbated with B deficiency. Aluminum toxicity indicated disorganized distribution of HG (homogalacturonan) epitopes with higher accumulation of apoplastic aluminum. Nevertheless, B supply improved root elongation, and reduced the aluminum uptake. Taken together, it is concluded that B application can reduce aluminum toxicity and improve root elongation by decreasing Al3+ accumulation to cell wall, alteration in the cell wall structure and reducing the distribution of HG epitopes in the roots of trifoliate (Poncirus trifoliate) orange.


Asunto(s)
Aluminio/química , Boro/farmacología , Pared Celular/efectos de los fármacos , Epítopos/química , Raíces de Plantas/efectos de los fármacos , Poncirus/efectos de los fármacos , Bencenosulfonatos/química , Pared Celular/ultraestructura , Microscopía Confocal , Pectinas/química , Raíces de Plantas/crecimiento & desarrollo , Suelo/química , Espectroscopía Infrarroja por Transformada de Fourier
18.
Ecotoxicol Environ Saf ; 165: 25-35, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30173023

RESUMEN

Aluminum is a major limiting abiotic factor for plant growth and productivity on acidic soils. The primary disorder of aluminum toxicity is the rapid cessation of root elongation. The root apex is the most sensitive part of this organ. Although significant literature evidence and hypothesis exist on aluminum toxicity, the explicit mechanism through which aluminum ceases root growth is still indefinable. The mechanisms of tolerance in plants have been the focus of intense research. Some plant species growing on acidic soils have developed tolerance mechanisms to overcome and mitigate aluminum toxicity, either by avoiding entry of Al3+ into roots (exclusion mechanism) or by being able to counterbalance toxic Al3+ engrossed by the root system (internal tolerance mechanism). Genes belonging to ALMT (Aluminum-activated malate transporter) and MATE (Multidrug and toxin compounds extrusion) have been identified that are involved in the aluminum-activated secretion of organic acids from roots. However, different plant species show different gene expression pattern. On the other hand, boron (B) (indispensable micronutrient) is a promising nutrient in the tolerance to aluminum toxicity. It not only hinders the adsorption of aluminum to the cell wall but also improves plant growth. This review mainly explains the critical roles of organic acid and B-induced tolerance to aluminum by summarizing the mechanisms of ALMT, MATE, internal detoxification, molecular traits and genetic engineering of crops.


Asunto(s)
Aluminio/toxicidad , Boro/fisiología , Plantas/efectos de los fármacos , Ácidos/metabolismo , Aluminio/metabolismo , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Ingeniería Genética , Malatos/metabolismo , Transportadores de Anión Orgánico/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Plantas/genética , Plantas/metabolismo , Suelo/química
19.
Ecotoxicol Environ Saf ; 153: 107-115, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29425841

RESUMEN

Aluminum (Al) toxicity is a major restriction for crops production on acidic soils. The primary symptom of aluminum toxicity is visible in the roots of plants. Recently, several studies reported the alleviation of Al toxicity by the application of Boron (B), however, the information how B alleviates Al toxicity is not well understood. Thus, we investigated the ameliorative response of B on Al-induced growth inhibition, oxidative damages, and variations in the cell wall components in trifoliate orange roots. The results indicated that plants under Al stress experienced a substantial decrement in root length and overall plant growth. The supply of B improved the root elongation by eliminating oxidative stress, membrane peroxidation, membrane leakage, and cell death produced under Al toxicity. Moreover, accumulation of Al on the cell wall and alteration in the cell wall components might be one of the causes resulting in the quick inhibition of root elongation under B-starvation circumstances by providing susceptible negative charges on pectin matrix for binding of Al. The results provide a useful understanding of the insight into mechanisms of B-induced mitigation of Al toxicity especially in the trifoliate orange that might be helpful in the production of crops on acidic soils.


Asunto(s)
Aluminio/toxicidad , Boro/farmacología , Estrés Oxidativo/efectos de los fármacos , Poncirus/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , China , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Poncirus/crecimiento & desarrollo , Poncirus/metabolismo , Suelo/química
20.
J Environ Manage ; 208: 149-158, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29257991

RESUMEN

Aluminium (Al) toxicity is the most important soil constraint for plant growth and development in acid soils (pH < 5.5) globally in agricultural regions. Boron (B) is an essential micronutrient for the growth and development of higher plants. The results of previous studies propose that B might ameliorate Al toxicity; however, none of the studies have been conducted on trifoliate orange to study this effect. Thus, a study was carried out in hydroponics comprising of two different Al concentrations, 0 and 400 µM. For every concentration, two B treatments (0 and 10 µM as H3BO3) were applied to investigate the B-induced alleviation of Al toxicity and exploring the underneath mechanisms. The results revealed that Al toxicity under B deficiency severely hampered the root growth and physiology of plant, caused oxidative stress and membrane damage, leading to severe root injury and damage. However, application of B under Al toxicity improved the root elongation and photosynthesis, while reduced Al uptake and mobilization into plant parts. Moreover, B supply regulated the activities of antioxidant enzymes, proline, secondary metabolites (phenylalanine ammonia lyase and polyphenol oxidase) contents, and stabilized integrity of proteins. Our study results imply that B supply promoted root growth as well as defense system by reducing reactive oxygen species (ROS) and Al concentrations in plant parts thus B induced alleviation of Al toxicity; a fact that might be significant for higher productivity of agricultural plants grown in acidic conditions.


Asunto(s)
Aluminio/toxicidad , Citrus , Poncirus , Antioxidantes , Boro , Raíces de Plantas/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda