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1.
Inorg Chem ; 63(5): 2776-2786, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38266170

RESUMEN

Developing efficient heterogeneous catalysts for chemical fixation of CO2 to produce high-value-added chemicals under mild conditions is highly desired but still challenging. Herein, we first reported an approach to prepare a novel catalyst (Ag@NCNFs), featuring Ag nanoparticles (NPs) embedded within porous nitrogen-doped carbon nanofibers (NCNFs), via growing a Ag metal-organic framework on one-dimensional electrospun nanofibers followed by pyrolysis. Benefiting from the abundant nitrogen species and porous structure, Ag NPs is well dispersed in the obtained Ag@NCNFs. Catalytic studies indicated that Ag@NCNFs exhibited excellent catalytic activity for the three-component coupling reaction of CO2, secondary amines, and propargylic alcohols to generate ß-oxopropylcarbamates under mild conditions with a turnover number (TON) of 16.2, and it can be recycled and reused at least 5 times without an obvious decline in catalytic activity. The reaction mechanism was clearly clarified by FTIR, NMR, 13C isotope labeling, control experiments, and density functional theory calculations. The results suggest that Ag@NCNFs and 1,8-diazabicyclo[5.4.0]undec-7-ene can synergistically activate propargylic alcohol to react with CO2, and then the generated α-alkylidene cyclic carbonate was invaded by secondary amine to produce ß-oxopropylcarbamate. Importantly, to the best of our knowledge, this is the first experimental and theoretical investigation on this reaction.

2.
Inorg Chem ; 63(29): 13450-13458, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38959430

RESUMEN

The conversion of CO2 to generate high-value-added chemicals has become one of the hot research topics in green synthesis. Thereinto, the cyclization reaction of propargylic amines with CO2 is highly attractive because the resultant oxazolidinones are widely found in pharmaceutical chemistry. Cu(I)-based metal-organic frameworks (MOFs) as catalysts exhibit promising application prospects for CO2 conversion. However, their practical application was greatly limited due to Cu(I) being liable to disproportionation or oxidization. Herein, the solid copper(I) iodide thorium-based porous framework {[Cu5I6Th6(µ3-O)4(µ3-OH)4(H2O)10(L)10]·OH·4DMF·H2O}n (1) (HL = 2-methylpyridine-4-carboxylic acid) constructed by [Th6] clusters and [CuxIy] subunits was successfully prepared and structurally characterized. To our knowledge, this is the first copper(I) iodide-based actinide organic framework. Catalytic investigations indicate that 1 can effectively catalyze the cyclization of propargylic amines with CO2 under ambient conditions, which can be reused at least five times without a remarkable decline of catalytic activity. Importantly, 1 exhibits excellent chemical stability and the oxidation state of Cu(I) in it can remain stable under various conditions. This work can provide a valuable strategy for the synthesis of stable Cu(I)-MOF materials.

3.
J Stroke Cerebrovasc Dis ; 33(5): 107640, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38387760

RESUMEN

OBJECTIVE: This study aims to investigate the impact of first pass effect (FPE) on outcomes in the posterior circulation acute ischemic stroke (PC-AIS) and the independent predictors of FPE. METHODS: This was a multicenter, retrospective study. PC-AIS patients who underwent endovascular treatment were reviewed. The cohort achieving complete or nearly complete reperfusion (defined as expanded treatment in cerebralischemia [eTICI] ≥ 2c) was categorized into the FPE and multiple pass effect (MPE) groups. FPE was defined as achieving eTICI ≥ 2c with a single pass and without the use of rescue therapy. Modified FPE (mFPE) was defined as meeting the criteria for FPE but with eTICI ≥ 2b. The association of FPE with 90-day clinical outcomes and predictors for FPE were both investigated. RESULTS: The study included a total of 328 patients, with 69 patients (21 %) in the FPE group. For primary outcome, FPE had a significant higher favorable outcome (mRS ≤ 3) rate than MPE (65.2 % vs. 44.8 %, p = 0.003). Similar outcomes were observed in the mFPE. Furthermore, FPE was significantly associated with favorable outcome (adjusted OR 2.23, 95 % CI 1.06-4.73, p = 0.036). Positive predictors for FPE included occlusion in the distal basilar artery, the first-line aspiration or combination, and cardioembolic etiology. Negative predictors for FPE included hypertension and general anesthesia. CONCLUSION: For PC-AIS patients due to large or medium vessel occlusion, FPE is associated with favorable clinical outcomes. The first-line techniques of aspiration or combination, as well as avoiding general anesthesia, contribute to a better realization of FPE.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Humanos , Procedimientos Endovasculares/métodos , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/terapia , Estudios Retrospectivos , Resultado del Tratamiento
4.
Int Heart J ; 65(2): 292-299, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38556337

RESUMEN

B-type natriuretic peptide (BNP) possesses protective cardiovascular properties; however, there has not been sufficient serious consideration of the side effects of BNP. As for sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a), it was once considered a new target for the treatment of heart failure (HF). Nevertheless, clinical trials of SERCA2a gene therapy in HF have finally become unsuccessful. Research has found that elevated BNP levels and decreased SERCA2a expression are two important HF characteristics, which are always negatively correlated. We hypothesize that BNP inhibits SERCA2a expression and, therefore, exerts negative effects on SERCA2a expression and function.The effects of BNP on endogenous SERCA2a expression and function were tested in mice with HF induced by transverse aortic constriction and neonatal rat cardiomyocytes (NRCM). Furthermore, to verify the effects of BNP on exogenous SERCA2a gene transduction efficacy, BNP was added to the myocardium and cardiomyocytes infected with an adenovirus overexpressing SERCA2a.In vivo, BNP levels were increased, SERCA2a expression was reduced in both the BNP intervention and HF groups, and BNP reduced the overexpressed exogenous SERCA2a protein in the myocardium. Our in vitro data showed that BNP dose-dependently inhibited the total and exogenous SERCA2a expression in NRCM by activating the cGMP-dependent protein kinase G. BNP also inhibited the effects of SERCA2a overexpression on Ca2+ transience in NRCM.The expression and function of endogenous and exogenous SERCA2a are inhibited by BNP. The opposite relationship between BNP and SERCA2a should be given serious attention in the treatment of HF via BNP or SERCA2a gene therapy.


Asunto(s)
Insuficiencia Cardíaca , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico , Ratas , Ratones , Animales , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Péptido Natriurético Encefálico/metabolismo , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo
5.
Nano Lett ; 21(7): 3033-3043, 2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33755480

RESUMEN

The poor drug delivery to cerebral ischemic regions is a key challenge of ischemic stroke treatment. Inspired by the intriguing blood-brain barrier (BBB)-penetrating ability of 4T1 cancer cells upon their brain metastasis, we herein designed a promising biomimetic nanoplatform by camouflaging a succinobucol-loaded pH-sensitive polymeric nanovehicle with a 4T1 cell membrane (MPP/SCB), aiming to promote the preferential targeting of cerebral ischemic lesions to attenuate the ischemia/reperfusion injury. In transient middle cerebral artery occlusion (tMCAO) rat models, MPP/SCB could be preferentially delivered to the ischemic hemisphere with a 4.79-fold higher than that in the normal hemisphere. Moreover, MPP/SCB produced notable enhancement of microvascular reperfusion in the ischemic hemisphere, resulting in a 69.9% reduction of infarct volume and showing remarkable neuroprotective effects of tMCAO rats, which was superior to the counterpart uncamouflaged nanovehicles (PP/SCB). Therefore, this design provides a promising nanoplatform to target the cerebral ischemic lesions for ischemic stroke therapy.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Neoplasias , Daño por Reperfusión , Accidente Cerebrovascular , Animales , Isquemia Encefálica/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Ratas , Accidente Cerebrovascular/tratamiento farmacológico
6.
Magn Reson Med ; 86(2): 943-953, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33723890

RESUMEN

PURPOSE: Chemical exchange saturation transfer (CEST) MRI is versatile for measuring the dilute labile protons and microenvironment properties. However, the use of insufficiently long RF saturation duration (Ts) and relaxation delay (Td) may underestimate the CEST measurement. This study proposed a quasi-steady-state (QUASS) CEST analysis for robust CEST quantification. METHODS: The CEST signal evolution was modeled as a function of the longitudinal relaxation rate during Td and spin-lock relaxation rate during Ts, from which the QUASS-CEST effect is derived. Numerical simulation and in vivo rat glioma MRI experiments were conducted at 11.7 T to compare the apparent and QUASS-CEST results obtained under different Ts/Td of 2 seconds/2 seconds and 4 seconds/4 seconds. Magnetization transfer and amide proton transfer effects were resolved using a multipool Lorentzian fitting and evaluated in contralateral normal tissue and tumor regions. RESULTS: The simulation showed the dependence of the apparent CEST effect on Ts and Td, and such reliance was mitigated with the QUASS algorithm. Animal experiment results showed that the apparent magnetization transfer and amide proton transfer effects and their contrast between contralateral normal tissue and tumor regions increased substantially with Ts and Td. In comparison, the QUASS magnetization transfer and amide proton transfer effects and their difference between contralateral normal tissue and tumor exhibited little dependence on Ts and Td. In addition, the apparent magnetization transfer and amide proton transfer were significantly smaller than the corresponding QUASS indices (P < .05). CONCLUSION: The QUASS-CEST algorithm enables robust CEST quantification and offers a straightforward approach to standardize CEST experiments.


Asunto(s)
Glioma , Algoritmos , Animales , Dimaprit/análogos & derivados , Glioma/diagnóstico por imagen , Imagen por Resonancia Magnética , Protones , Ratas , Microambiente Tumoral
7.
Appl Microbiol Biotechnol ; 105(5): 2109-2121, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33587158

RESUMEN

Intramammary bacterial infection, the most common cause of mastitis, is the most costly disease in dairy cattle in the US and reason for antibiotic usage. Ceftiofur, a third-generation cephalosporin, is generally used to treat such disease, but it has a high treatment failure rate. Though the reason is not known clearly, it is hypothesized that multiple factors are associated with the treatment failure. In this study, we analyzed 169 milk samples from cows with mastitis in two independent dairy farms (Farm A and B) in which 19.4% (Farm A) and 14.3% (Farm B) of the antibiotic treated cows were not cured. The prevalence of cephalosporin-resistant bacteria (CRB) in milk was 72.0% and 42.1% in Farm A and B, respectively. Nineteen and nine bacterial genera were identified in Farm A and B respectively, with the most abundant genus being Staphylococcus (27.1%; Farm A) and Bacillus (63.5%; Farm B). However, no strong relationship between the treatment failure rate and the CRB prevalence was observed. Furthermore, the metagenomic analysis showed no significant differences in the α- and ß-diversities of microbiota in milk samples from cured and uncured cows, suggesting that antibiotic-resistant bacteria were not the sole reason for the antibiotic treatment failure. KEY POINTS: • The mastitic milk samples had high prevalence of cephalosporin-resistant bacteria (CRB). • The CRB identified belong to diversified species. • Antibiotic treatment failure was not solely caused by the abundance of CRB.


Asunto(s)
Mastitis Bovina , Mastitis , Microbiota , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias/genética , Bovinos , Femenino , Humanos , Mastitis/tratamiento farmacológico , Mastitis Bovina/tratamiento farmacológico , Leche
8.
J Med Genet ; 55(5): 287-296, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29478009

RESUMEN

Sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a) is a target of interest in gene therapy for heart failure with reduced ejection fraction (HFrEF). However, the results of an important clinical study, the Calcium Upregulation by Percutaneous Administration of Gene Therapy in Cardiac Disease (CUPID) trial, were controversial. Promising results were observed in the CUPID 1 trial, but the results of the CUPID 2 trial were negative. The factors that caused the controversial results remain unclear. Importantly, enrolled patients were required to have a higher plasma level of B-type natriuretic peptide (BNP) in the CUPID 2 trial. Moreover, BNP was shown to inhibit SERCA2a expression. Therefore, it is possible that high BNP levels interact with treatment effects of SERCA2a gene transfer and accordingly lead to negative results of CUPID 2 trial. From this point of view, effects of SERCA2a gene therapy should be explored in heart failure with preserved ejection fraction, which is characterised by lower BNP levels compared with HFrEF. In this review, we summarise the current knowledge of SERCA2a gene therapy for heart failure, analyse potential interaction between BNP levels and therapeutic effects of SERCA2a gene transfer and provide directions for future research to solve the identified problems.


Asunto(s)
Terapia Genética , Insuficiencia Cardíaca/terapia , Péptido Natriurético Encefálico/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , Señalización del Calcio/genética , Ensayos Clínicos como Asunto , Insuficiencia Cardíaca/genética , Humanos , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/uso terapéutico
9.
Microorganisms ; 12(8)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39203518

RESUMEN

Vancomycin-resistant enterococci (VRE) commonly colonize the gut of individuals with hematologic malignancies or undergoing hematopoietic cell transplant (HCT) and may cause bacteremia. In 2012, we identified VRE isolates from patients and patients' rooms and showed transmission networks of highly genetically related daptomycin-resistant (DR)-VRE strains. This is a follow-up study performing whole-genome sequencing (WGS) and phylogenetic analyses on 82 clinical VRE strains isolated from stools and blood cultures of patients with leukemia and HCT between 2015 and 2019. Here, we observed transmission of highly genetically related strains between rooms on the same or on different floors, including a DR-VRE strain identified in 2012. Eleven of twenty-eight patients with DR-VRE were never exposed to daptomycin, suggesting horizontal transmission. Fifteen of the twenty-eight patients with DR-VRE died within 30 days of positive blood cultures. Amongst those, one DR-VRE strain belonging to ST1471 had the virulence gene bopD responsible for biofilm formation. Additionally, to our knowledge, this is the first report of a DR-VRE strain belonging to ST323 in the United States. In summary, our study demonstrated the emergence and persistence of VRE strains, especially DR-VRE, in our hospital. Adding WGS to routine infection control measures may timely identify potential horizontal VRE transmission including multi-drug-resistant isolates.

10.
Food Sci Biotechnol ; 32(12): 1653-1664, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37780593

RESUMEN

Microbial biofilms are prevalent in various environments and pose significant challenges to food safety and public health. The biofilms formed by pathogens can cause food spoilage, foodborne illness, and infectious diseases, which are difficult to treat due to their enhanced antimicrobial resistance. While the composition and development of biofilms have been widely studied, their profound impact on food, the food industry, and public health has not been sufficiently recapitulated. This review aims to provide a comprehensive overview of microbial biofilms in the food industry and their implication on public health. It highlights the existence of biofilms along the food-producing chains and the underlying mechanisms of biofilm-associated diseases. Furthermore, this review thoroughly summarizes the enhanced understanding of microbial biofilms achieved through machine learning approaches in biofilm research. By consolidating existing knowledge, this review intends to facilitate developing effective strategies to combat biofilm-associated infections in both the food industry and public health.

11.
Sci Rep ; 13(1): 20442, 2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-37993625

RESUMEN

Excessive intake of oil, salt and sugar is closely associated with the prevalence of non-communicable chronic diseases (NCDs). Canteen staff's knowledge, attitude and practice (KAP) about oil, salt and sugar directly affect the content in dishes and the consumers' intake. However, no valid questionnaire is used to assess KAP among canteen staff about the "oil, salt and sugar". Therefore, the present study aimed to establish and validate a questionnaire to evaluate the KAP of canteen staff about the "oil, salt and sugar". This cross-sectional study was conducted among canteen staff randomly selected from three college canteens. Participants completed the questionnaire and retested it two weeks later. Internal and test-retest reliability were assessed using Cronbach's α and Pearson correlation coefficients, respectively. Validity was assessed using the exploratory factor analysis. 100 participants finished the questionnaire, of which 66% were females with a mean age of 40.3 ± 10.5 years. The Cronbach's α coefficients of the total questionnaire and Knowledge, Attitude and Practice dimensions were 0.822, 0.830, 0.752 and 0.700, respectively. The test-retest reliability coefficient was 0.968. In exploratory factor analysis, nine common factors were extracted, with 26 items, and the cumulative contribution rate was 70.9%. The questionnaire had a satisfactory property for measuring the KAP of the "oil, salt and sugar" among canteen staff in China.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Azúcares , Femenino , Humanos , Adulto , Persona de Mediana Edad , Masculino , Reproducibilidad de los Resultados , Estudios Transversales , Encuestas y Cuestionarios , Psicometría/métodos
12.
Front Cell Neurosci ; 16: 1075640, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36505515

RESUMEN

Oxidative damage generally exists in stroke and impairs stem cells' survival; however, the problem is difficult to treat. In order to help stem cells to resist this damage, we inserted a magnetotactic bacteria (MB) gene, mms6, into the neural stem cell genome by lentiviral transfection. It was found that the transfection of mms6 significantly improved the survival rate of stem cells in the condition of iron overload but not hypoxia. The bioenergetic profile also revealed that iron overloading weakened the mitochondrial respiration and spare respiration capacity of stem cells, but that these were enhanced after the expression of mms6. Additionally, Western blotting (WB) data revealed that mms6 upregulated the expression of glutathione peroxidase (GPX4), which protected stem cells from oxidative damage and ferroptosis. In order to determine the possible mechanisms, we analyzed the interactions between the MMS6 protein, Fe2+, and GPX4 via analog computation. The predicted models found that the MMS6 protein had a direct chelating site in the region of M6A with divalent iron; it also had weak binding with GPX4. Taken together, the magnetotactic bacterial gene mms6 protected stem cells from oxidative damage via binding with Fe2+, which could help them adapt to the microenvironment of stroke.

13.
Adv Sci (Weinh) ; 9(7): e2104935, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35023300

RESUMEN

Surgeons face challenges in intraoperatively defining margin of brain tumors due to its infiltrative nature. Extracellular acidosis caused by metabolic reprogramming of cancer cells is a reliable marker for tumor infiltrative regions. Although the acidic margin-guided surgery shows promise in improving surgical prognosis, its clinical transition is delayed by having the exogenous probes approved by the drug supervision authority. Here, an intelligent surface-enhanced Raman scattering (SERS) navigation system delineating glioma acidic margins without administration of exogenous probes is reported. With assistance of this system, the metabolites at the tumor cutting edges can be nondestructively transferred within a water droplet to a SERS chip with pH sensitivity. Homemade deep learning model automatically processes the Raman spectra collected from the SERS chip and delineates the pH map of tumor resection bed with increased speed. Acidity correlated cancer cell density and proliferation level are demonstrated in tumor cutting edges of animal models and excised tissues from glioma patients. The overall survival of animal models post the SERS system guided surgery is significantly increased in comparison to the conventional strategy used in clinical practice. This SERS system holds the promise in accelerating clinical transition of acidic margin-guided surgery for solid tumors with infiltrative nature.


Asunto(s)
Acidosis , Neoplasias Encefálicas , Glioma , Animales , Neoplasias Encefálicas/cirugía , Glioma/patología , Glioma/cirugía , Humanos , Márgenes de Escisión , Espectrometría Raman
14.
Ultrason Sonochem ; 79: 105787, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34634550

RESUMEN

The effects of multi-frequency ultrasound on surface decontamination and structural characteristics of large yellow croaker (Pseudosciaena crocea) during refrigerated storage were evaluated. The results of total viable counts (TVCs) and psychrophilic bacteria counts (PBCs) demonstrated that multi-frequency ultrasound retarded the growth of microorganisms. The bacteriostatic effect was positively correlated with the increase of ultrasound frequencies. However, compared with triple-frequency ultrasound (TUS, 20/28/40 kHz) treatment, dual-frequency ultrasound (DUS, 20/28 kHz) treatment had higher water-holding capacity (WHC) and immobilized water content, better texture characteristics, lower pH and total volatile basic nitrogen (TVB-N). Through the results of myofibrillar fragmentation index (MFI), intrinsic fluorescence intensity (IFI) and atomic force microscope (AFM), multi-frequency ultrasound could effectively stabilize the myofibrillar protein structure of refrigerated large yellow croaker, which could maintain better texture characteristics. The effects of DUS were the most significant. Therefore, multi-frequency ultrasound treatment could inhibit the growth of microorganisms and improve the structural characteristics of large yellow croaker during refrigerated storage.


Asunto(s)
Descontaminación , Perciformes , Animales , Nitrógeno , Ultrasonido , Agua
15.
Microbiol Resour Announc ; 10(41): e0080821, 2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34647798

RESUMEN

New Delhi metallo-ß-lactamase (NDM)-producing Enterobacteriaceae pose a great threat to public health globally. Most known NDM-producing Enterobacteriaceae are associated with human hospital or community infections. Here, we report the draft genome sequence of an NDM-1-encoding Klebsiella pneumoniae strain isolated from feral swine (Sus scrofa) captured in Florida, USA.

16.
Microbiol Resour Announc ; 10(11)2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33737360

RESUMEN

Burkholderia cepacia complex (Bcc) bacteria are opportunistic pathogens with high transmissibility and mortality. Here, we report the draft genome sequence of a Bcc strain isolated from a deep abscess culture in an immunocompetent patient with no relevant prior medical history.

17.
Front Microbiol ; 12: 772863, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34745079

RESUMEN

Calf diarrhea is one of the most concerning challenges facing both the dairy and beef cattle industry. Maintaining healthy gut microbiota is essential for preventing gastrointestinal disorders. Here, we observed significantly less bacterial richness in the abnormal feces with watery or hemorrhagic morphology compared to the normal solid feces. The normal solid feces showed high relative abundances of Osllospiraceae, Christensenellaceae, Barnesiella, and Lactobacillus, while the abnormal feces contained more bacterial taxa of Negativicutes, Tyzzerella, Parasutterella, Veillonella, Fusobacterium, and Campylobacter. Healthy calves had extensive bacterial-bacterial correlations, with negative correlation between Lactobacillus and potential diarrheagenic Escherichia coli-Shigella, but not in the abnormal feces. We isolated Lactobacillus species (L. reuteri, L. johnsonii, L. amylovorus, and L. animalis), with L. reuteri being the most abundant, from the healthy gut microbiota. Isolated Lactobacillus strains inhibited pathogenic strains including E. coli K88 and Salmonella Typhimurium. These findings indicate the importance of a diverse gut microbiota in newborn calf's health and provide multiple potential probiotics that suppress pathogen colonization in the gastrointestinal tract to prevent calf diarrhea.

18.
JAC Antimicrob Resist ; 3(1): dlab032, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34223104

RESUMEN

BACKGROUND: NDM-producing Enterobacteriaceae are a major clinical concern worldwide. We characterized NDM-positive pathogens isolated from patients and assessed the dissemination patterns of the bla NDM genes in a hospital setting. METHODS: Eleven NDM-positive Enterobacteriaceae (three Enterobacter hormaechei, six Klebsiella pneumoniae and two Escherichia coli) were isolated from nine patients over a 1 year period. Antimicrobial susceptibility was assessed by MICs. A combination of short- and long-read WGS was used for genome analysis. Clinical treatment history of patients was linked with genetic features of individual isolates to investigate the dissemination patterns of the bla NDM genes and NDM-positive strains. RESULTS: bla NDM in clonal K. pneumoniae were transmitted between two patients. In other instances, an identical IncC plasmid encoding NDM-1 was transmitted between E. coli and K. pneumoniae isolated from the same patient, and an IncX3 plasmid, carrying bla NDM-1 or bla NDM-5, was harboured in non-clonal E. hormaechei. Varying patterns of IS elements were identified as a critical transmission mechanism in association with bla NDM genes. CONCLUSIONS: Multiple transmission patterns were identified in hospitalized patients, including dissemination of clonal bacterial strains carrying resistance genes and horizontal transfer of resistance genes among divergent bacterial strains. Controlling spread of NDM is complex: while attention to standard infection control practices is critically important, this needs to be matched by aggressive efforts to limit unnecessary antimicrobial use, to minimize the selection for and risk of transfer of 'high mobility' resistance genes among Enterobacteriaceae.

19.
ACS Appl Mater Interfaces ; 11(17): 15241-15250, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30896915

RESUMEN

Glioma is the most frequent form of malignant brain tumors. Surgical debulking is a major strategy for glioma treatment. However, there is a great challenge for the neurosurgeons to intraoperatively identify the true margins of glioma because of its infiltrative nature. Tumor residues or microscopic satellite foci left in the resection bed are the main reasons leading to early recurrence as well as poor prognosis. In this study, a surface-enhanced resonance Raman scattering (SERRS) probe was developed to intraoperatively guide glioma resection. In this probe, molecular reporters with absorptive maxima at the near-infrared wavelength range were covalently functionalized on the surface of gold nanostars. This SERRS probe demonstrated an ultrahigh sensitivity with a detection limit of 5.0 pM in aqueous solution. By the development of glioma xenografts in a mouse dorsal skin window chamber, extravasation of this probe from leaky tumor vasculature as functions of time and distance to tumor boundary was investigated. Importantly, the invasive margin of the tumor xenograft was demarcated by this probe with a high signal-to-background ratio. Preoperative magnetic resonance imaging (MRI) first defined the position of orthotopic glioma xenografts in the brain of rat models, and the craniotomy plan was designed. The brain tumor was then excised intraoperatively step-by-step with the assistance of a handheld Raman scanner till the Raman signals of the probe completely disappeared in the resection bed. Notably, longitudinal MRI showed that SERRS-guided surgery significantly reduced the tumor recurrence rate and improved the overall survival of rat models compared with the white light-guided surgery. Overall, this work demonstrates the prognostic benefit of SERRS-guided glioma surgery in animal models. Because delineation of tumor-invasive margins is a common challenge faced by the surgeons, this SERRS probe with a picomolar detection limit holds the promise in improving the surgical outcome of different types of infiltrated tumors.


Asunto(s)
Neoplasias Encefálicas/cirugía , Glioma/cirugía , Espectrometría Raman/métodos , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Glioma/diagnóstico por imagen , Glioma/patología , Oro/química , Indoles/química , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Desnudos , Nanoestructuras/química , Recurrencia Local de Neoplasia , Pronóstico , Ratas , Ratas Sprague-Dawley , Cirugía Asistida por Computador , Trasplante Heterólogo , Trasplante Homólogo
20.
Zhonghua Yu Fang Yi Xue Za Zhi ; 41 Suppl: 73-6, 2007 Jun.
Artículo en Zh | MEDLINE | ID: mdl-17767863

RESUMEN

OBJECTIVE: To understand the trend of gastric cancer mortality based on the exploration of the death data from 1970 to 2004 in Zhaoyuan County. METHODS: The death data of 1970-1974 were collected from the first malignant tumor death survey of China, and the data of 1985-2004 were derived from the cancer registration network of Zhaoyuan. The appreciation indexes were crude mortality rate and standardized mortality rates by the percentages of Chinese population in 1982 and the percentages of world population in 1966. RESULTS: The crude mortality rates in the five periods of 1970-1974, 1985-1989, 1990-994, 1995-1999, and 2000-2004 were 34.94, 44.34, 40.05, 48.73, and 40.18 per 100,000, respectively; the standardized mortality rates by Chinese population were 30.82, 30.35, 27.78, 31.63, and 20.10 per 100,000, respectively. The gastric cancer mortality remained stability from 1970 to 1999, however, the standardized mortality rate of gastric cancer in 2000-2004 declined by 34.8% compared with that in 1970-1974. The study also observed that the highest age-specific gastric cancer mortality, in the past 35 years, has been postponed by 10 years. And, the gastric cancer mortality ranked from top first to top three. CONCLUSION: There is a decreasing trend for the incidence of stomach cancer and this might be associated with the changes of dietary consumption and pattern.


Asunto(s)
Neoplasias Gástricas/mortalidad , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Sistema de Registros , Estudios Retrospectivos
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