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1.
Angiogenesis ; 25(3): 397-410, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35212873

RESUMEN

Anthrax protective antigen (PA) is a potent inhibitor of pathological angiogenesis with an unknown mechanism. In anthrax intoxication, PA interacts with capillary morphogenesis gene 2 (CMG2) and tumor endothelial marker 8 (TEM8). Here, we show that CMG2 mediates the antiangiogenic effects of PA and is required for growth-factor-induced chemotaxis. Using specific inhibitors of CMG2 and TEM8 interaction with natural ligand, as well as mice with the CMG2 or TEM8 transmembrane and intracellular domains disrupted, we demonstrate that inhibiting CMG2, but not TEM8 reduces growth-factor-induced angiogenesis in the cornea. Furthermore, the antiangiogenic effect of PA was abolished when the CMG2, but not the TEM8, gene was disrupted. Binding experiments demonstrated a broad ligand specificity for CMG2 among extracellular matrix (ECM) proteins. Ex vivo experiments demonstrated that CMG2 (but not TEM8) is required for PA activity in human dermal microvascular endothelial cell (HMVEC-d) network formation assays. Remarkably, blocking CMG2-ligand binding with PA or CRISPR knockout abolishes endothelial cell chemotaxis but not chemokinesis in microfluidic migration assays. These effects are phenocopied by Rho inhibition. Because CMG2 mediates the chemotactic response of endothelial cells to peptide growth factors in an ECM-dependent fashion, CMG2 is well-placed to integrate growth factor and ECM signals. Thus, CMG2 targeting is a novel way to inhibit angiogenesis.


Asunto(s)
Quimiotaxis , Células Endoteliales , Neovascularización Patológica , Receptores de Péptidos , Animales , Células Endoteliales/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Ligandos , Ratones , Receptores de Péptidos/genética , Receptores de Péptidos/metabolismo
2.
Antibiotics (Basel) ; 10(7)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202216

RESUMEN

BACKGROUND: The emergence of plasmid-mediated antibiotic resistance in Escherichia coli in water resources could pose a serious threat to public health. The study aims to investigate the dispersion of plasmid-mediated antibiotic-resistant E. coli from six rivers in Sarawak and two aquaculture farms in Borneo. METHODS: A total of 74 water samples were collected for the determination of their bacteria colony count. An IMViC test identified 31 E. coli isolates and tested their susceptibility against twelve clinically important antibiotics. The extraction of plasmid DNA was done using alkali lysis SDS procedures. Characteristics, including plasmid copy number, molecular weight size, resistance rate and multiple antibiotic resistance (MAR), were assessed. RESULTS: Our findings revealed that bacterial counts in rivers and aquaculture farms ranged from log 2.00 to 3.68 CFU/mL and log 1.70 to 5.48 cfu/mL, respectively. Resistance to piperacillin (100%) was observed in all E. coli; resistance to amoxicillin (100%) and ampicillin (100%) was observed in E. coli found in aquaculture farms; resistance to streptomycin (93%) was observed in E. coli found in rivers. All E. coli were resistant to ≥2 antibiotics and formed 26 MAR profiles, ranging from an index of 0.17 to 0.83, indicating that there are high risks of contamination. Some (48.4%) of the E. coli were detected with plasmids (1.2 to >10 kb), whereas 51.6% of the E. coli did not harbor any plasmids. The plasmid copy numbers reported were one plasmid (n = 7), two plasmids (n = 4), ≥ two plasmids (4). E. coli isolated from the Muara Tuang River showed the highest-molecular-weight plasmids. A statistical analysis revealed that there is no significant correlation (r = 0.21, p = 0.253) between the number of plasmids and the MAR index of the tested isolates. CONCLUSION: The distribution of MAR in E. coli from rivers is higher compared to the aquaculture environment. Our study suggests that MAR in isolates could be chromosome-mediated. Our results suggest that riverbed sediments could serve as reservoirs for MAR bacteria, including pathogens, under different climatic conditions, and their analysis could provide information for public health concerns.

3.
PLoS One ; 15(3): e0229131, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32187181

RESUMEN

Predicting the number of defects in software at the method level is important. However, little or no research has focused on method-level defect prediction. Therefore, considerable efforts are still required to demonstrate how method-level defect prediction can be achieved for a new software version. In the current study, we present an analysis of the relevant information obtained from the current version of a software product to construct regression models to predict the estimated number of defects in a new version using the variables of defect density, defect velocity and defect introduction time, which show considerable correlation with the number of method-level defects. These variables also show a mathematical relationship between defect density and defect acceleration at the method level, further indicating that the increase in the number of defects and the defect density are functions of the defect acceleration. We report an experiment conducted on the Finding Faults Using Ensemble Learners (ELFF) open-source Java projects, which contain 289,132 methods. The results show correlation coefficients of 60% for the defect density, -4% for the defect introduction time, and 93% for the defect velocity. These findings indicate that the average defect velocity shows a firm and considerable correlation with the number of defects at the method level. The proposed approach also motivates an investigation and comparison of the average performances of classifiers before and after method-level data preprocessing and of the level of entropy in the datasets.


Asunto(s)
Modelos Teóricos , Proyectos de Investigación , Programas Informáticos , Predicción , Humanos , Aprendizaje Automático , Programas Informáticos/normas
4.
ACS Chem Biol ; 15(2): 587-596, 2020 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-32003961

RESUMEN

Capillary Morphogenesis Gene 2 protein (CMG2) is a transmembrane, integrin-like receptor and the primary receptor for the anthrax toxin. CMG2 also plays a role in angiogenic processes. However, the molecular mechanism that mediates the observed CMG2-related angiogenic effects is not fully elucidated. Previous studies have reported that CMG2 binds type IV collagen (Col-IV), a vital component of the vascular basement membrane, as well as other ECM proteins. Here, we further characterize the interaction between CMG2 and individual peptides from Col-IV and explore the effects of this interaction on angiogenesis. Using a peptide array, we observed that CMG2 preferentially binds peptide fragments of the NC1 (noncollagenous domain 1) domains of Col-IV. These domains are also known as the fragments arresten (from the α1 chain) and canstatin (from the α2 chain) and have documented antiangiogenic properties. A second peptide array was probed to map a putative peptide-binding epitope onto the Col-IV structure. A top hit from the initial array, a canstatin-derived peptide, binds to the CMG2 ligand-binding von Willebrand factor A (vWA) domain with a submicromolar affinity (peptide S16, Kd = 400 ± 200 nM). This peptide competes with anthrax protective antigen (PA) for CMG2 binding and does not bind CMG2 in the presence of EDTA. Together these data suggest that, like PA, S16 interacts with CMG2 at the metal-ion dependent adhesion site (MIDAS) of its vWA domain. CMG2 specifically mediates endocytic uptake of S16; both CMG2-/- endothelial cells and WT cells treated with PA show markedly reduced S16 uptake. Furthermore, S16 dramatically reduces directional endothelial cell migration with no impact on cell proliferation. These data demonstrate that this canstatin-derived peptide acts via CMG2 to elicit a marked effect on a critical process required for angiogenesis.


Asunto(s)
Colágeno Tipo IV/metabolismo , Endocitosis/fisiología , Fragmentos de Péptidos/metabolismo , Receptores de Péptidos/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Ratones , Unión Proteica , Dominios Proteicos , Receptores de Péptidos/química
5.
J Biol Chem ; 293(6): 2066-2078, 2018 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-29229777

RESUMEN

The bacterial flagellar motor is a self-assembling supramolecular nanodevice. Its spontaneous biosynthesis is initiated by the insertion of the MS ring protein FliF into the inner membrane, followed by attachment of the switch protein FliG. Assembly of this multiprotein complex is tightly regulated to avoid nonspecific aggregation, but the molecular mechanisms governing flagellar assembly are unclear. Here, we present the crystal structure of the cytoplasmic domain of FliF complexed with the N-terminal domain of FliG (FliF C -FliG N ) from the bacterium Helicobacter pylori Within this complex, FliF C interacted with FliG N through extensive hydrophobic contacts similar to those observed in the FliF C -FliG N structure from the thermophile Thermotoga maritima, indicating conservation of the FliF C -FliG N interaction across bacterial species. Analysis of the crystal lattice revealed that the heterodimeric complex packs as a linear superhelix via stacking of the armadillo repeat-like motifs (ARM) of FliG N Notably, this linear helix was similar to that observed for the assembly of the FliG middle domain. We validated the in vivo relevance of the FliG N stacking by complementation studies in Escherichia coli Furthermore, structural comparison with apo FliG from the thermophile Aquifex aeolicus indicated that FliF regulates the conformational transition of FliG and exposes the complementary ARM-like motifs of FliG N , containing conserved hydrophobic residues. FliF apparently both provides a template for FliG polymerization and spatiotemporally controls subunit interactions within FliG. Our findings reveal that a small protein fold can serve as a versatile building block to assemble into a multiprotein machinery of distinct shapes for specific functions.


Asunto(s)
Proteínas Bacterianas/metabolismo , Flagelos/química , Flagelos/metabolismo , Helicobacter pylori/metabolismo , Proteínas Bacterianas/genética , Cristalografía por Rayos X , Flagelos/genética , Helicobacter pylori/química , Helicobacter pylori/genética , Unión Proteica , Conformación Proteica , Thermotoga maritima/genética , Thermotoga maritima/metabolismo
6.
Chem Sci ; 7(10): 6534-6550, 2016 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-27928494

RESUMEN

Porphyrin-based photosynthetic reaction centre (PRC) mimics, ZnPQ-Q2HP-C60 and MP2Q-Q2HP-C60 (M = Zn or 2H), designed to have a similar special-pair electron donor and similar charge-separation distances, redox processes and photochemical reaction rates to those in the natural PRC from purple bacteria, have been synthesised and extensive photochemical studies performed. Mechanisms of electron-transfer reactions are fully investigated using femtosecond and nanosecond transient absorption spectroscopy. In benzonitrile, all models show picosecond-timescale charge-separations and the final singlet charge-separations with the microsecond-timescale. The established lifetimes are long compared to other processes in organic solar cells or other organic light harvesting systems. These rigid, synthetically flexible molecules provide the closest mimics to the natural PRC so far synthesised and present a future direction for the design of light harvesters with controllable absorption, redox, and kinetics properties.

7.
J Gastrointestin Liver Dis ; 25(3): 303-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27689193

RESUMEN

BACKGROUND AND AIMS: Pancreatic exocrine insufficiency may be under recognised in gastroenterological practice. We aimed to identify the prevalence of pancreatic insufficiency in secondary care gastroenterology clinics and determine if co-morbidity or presenting symptoms could predict diagnosis. A secondary aim was to assess response to treatment. METHODS: A dual centre retrospective analysis was conducted in secondary care gastroenterology clinics. Patients tested for pancreatic exocrine insufficiency with faecal elastase-1 (FEL-1) between 2009 and 2013 were identified in two centres. Demographics, indication and co-morbidities were recorded in addition to dose and response to pancreatic enzyme replacement therapy. Binary logistic regression was used to assess if symptoms or co-morbidities could predict pancreatic insufficiency. RESULTS: 1821 patients were tested, 13.1% had low FEL-1 (<200µg/g). This prevalence was sub-analysed with 5.4% having FEL-1 100-200µg/g (mild insufficiency) and 7.6% having faecal elastase readings <100µg/g. Low FEL-1 was most significantly associated with weight loss or steatorrhoea. Co-morbidity analysis showed that low levels were significantly associated with excess alcohol intake, diabetes mellitus or human immunodeficiency virus; 80.0% treated with enzyme supplements reported symptomatic benefit with no difference in response between high and low dose supplementation (p=0.761). CONCLUSION: Targeting the use of FEL-1 in individuals with specific symptoms and associated conditions can lead to improved recognition of pancreatic exocrine insufficiency in a significant proportion of secondary care patients. Intervening with lifestyle advice such as smoking cessation and minimising alcohol intake could improve outcomes. In addition, up to 80% of patients with low faecal elastase respond to supplementation.


Asunto(s)
Pruebas Enzimáticas Clínicas , Insuficiencia Pancreática Exocrina/diagnóstico , Insuficiencia Pancreática Exocrina/epidemiología , Gastroenterología , Elastasa Pancreática/análisis , Pruebas de Función Pancreática/métodos , Biomarcadores/análisis , Comorbilidad , Inglaterra/epidemiología , Terapia de Reemplazo Enzimático , Insuficiencia Pancreática Exocrina/tratamiento farmacológico , Heces/química , Humanos , Lipasa/administración & dosificación , Modelos Logísticos , Oportunidad Relativa , Valor Predictivo de las Pruebas , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Atención Secundaria de Salud , Esteatorrea/epidemiología , Factores de Tiempo , Resultado del Tratamiento , Pérdida de Peso
8.
J Microbiol Immunol Infect ; 49(5): 749-759, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27156242

RESUMEN

BACKGROUND/PURPOSE: Colonization, infection, and clonal dissemination of vancomycin-resistant enterococcus (VRE) have been reported in the literature. We aimed to investigate the incidence rate of VRE acquisition and route of transmission of VRE within the medical intensive care unit (ICU) to prove whether subclinical transmission occurs in medical ICUs. METHODS: Between March 1, 2012 and September 30, 2013, rectal cultures were obtained from all inpatients on admission and after admission to medical ICU. Strain types of VRE were determined by both multilocus sequence typing and pulsed-field gel electrophoresis. RESULTS: A total of 66 of the 405 rectal swab surveillance cultures obtained from 46 inpatients were positive for VRE, among which 27 inpatients were culture-positive for VRE on admission to medical ICU, and 19 inpatients were initially culture-negative but converted to culture-positive after admission. All isolates carried vanA gene consisting of 51 Enterococcus gallinarum, 13 Enterococcus faecium, and two Eenterococcus casseliflavus. Of the 51 E. gallinarum isolates, 40 were type ST 341, seven were ST 252, two were ST 78, and two were ST 64. The Enterococcus spp., MLST and PFGE subtypes were almost similar among these two groups of inpatients. Linezolid and tigecycline were most active against VRE in vitro. CONCLUSION: Subclinical VRE cross transmission may occur in ICU. Active surveillance and maximal barrier precautions of VRE are required at ICU with high colonization rate of VRE and shall be beneficial.


Asunto(s)
Antibacterianos/uso terapéutico , Enterococcus faecium/efectos de los fármacos , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/transmisión , Control de Infecciones/métodos , Resistencia a la Vancomicina , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Infección Hospitalaria/epidemiología , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Femenino , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Humanos , Unidades de Cuidados Intensivos , Linezolid/uso terapéutico , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Minociclina/análogos & derivados , Minociclina/uso terapéutico , Tipificación de Secuencias Multilocus , Taiwán/epidemiología , Tigeciclina , Vancomicina/uso terapéutico , Enterococos Resistentes a la Vancomicina/genética , Enterococos Resistentes a la Vancomicina/aislamiento & purificación
9.
Dalton Trans ; 43(47): 17624-34, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25178487

RESUMEN

Platinum(ii) bis(N-(4-ethynylphenyl)carbazole)bipyridine fullerene complexes, (Cbz)2-Pt(bpy)-C60 and ((t)BuCbz)2-Pt(bpy)-C60, were synthesized. Their photophysical properties were studied by electronic absorption and emission spectroscopy and the origin of the transitions was supported by computational studies. The electrochemical properties were also studied and the free energies for charge-separation and charge-recombination processes were evaluated. The photoinduced electron transfer reactions in the triads were investigated by femtosecond and nanosecond transient absorption spectroscopy. In dichloromethane, both triads undergo ultrafast charge separation from the (3)MLCT/LLCT excited state within 300 fs to yield their respective triplet charge-separated (CS) states, namely (Cbz)2˙(+)-Pt(bpy)-C60˙(-) and ((t)BuCbz)2˙(+)-Pt(bpy)-C60˙(-), and the CS states would undergo charge recombination to give the (3)C60* state, which subsequently decays to the ground state in 22-28 µs.

10.
J Am Chem Soc ; 136(28): 10041-52, 2014 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-24988327

RESUMEN

Donor-chromophore-acceptor triads, (PTZ)2-Pt(bpy)-C60 and ((t)BuPTZ)2-Pt(bpy)-C60, along with their model compound, (Ph)2-Pt(bpy)-C60, have been synthesized and characterized; their photophysical and electrochemical properties have been studied, and the origin of the absorption and emission properties has been supported by computational studies. The photoinduced electron transfer reactions have been investigated using the femtosecond and nanosecond transient absorption spectroscopy. In dichloromethane, (Ph)2-Pt(bpy)-C60 shows ultrafast triplet-triplet energy transfer from the (3)MLCT/LLCT excited state within 4 ps to give the (3)C60* state, while in (PTZ)2-Pt(bpy)-C60 and ((t)BuPTZ)2-Pt(bpy)-C60, charge-separated state forms within 400 fs from the (3)MLCT/LLCT excited state with efficiency of over 0.90, and the total efficiency with the contribution of (3)C60* is estimated to be 0.99. Although the forward electron transfer reactions are very rapid, the charge-separated state recombines to the singlet ground state at a time of hundreds of nanoseconds because of the difference in spin multiplicity between the charge-separated state and the ground state.

11.
ScientificWorldJournal ; 2014: 737626, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24982987

RESUMEN

Due to the budgetary deadlines and time to market constraints, it is essential to prioritize software requirements. The outcome of requirements prioritization is an ordering of requirements which need to be considered first during the software development process. To achieve a high quality software system, both functional and nonfunctional requirements must be taken into consideration during the prioritization process. Although several requirements prioritization methods have been proposed so far, no particular method or approach is presented to consider both functional and nonfunctional requirements during the prioritization stage. In this paper, we propose an approach which aims to integrate the process of prioritizing functional and nonfunctional requirements. The outcome of applying the proposed approach produces two separate prioritized lists of functional and non-functional requirements. The effectiveness of the proposed approach has been evaluated through an empirical experiment aimed at comparing the approach with the two state-of-the-art-based approaches, analytic hierarchy process (AHP) and hybrid assessment method (HAM). Results show that our proposed approach outperforms AHP and HAM in terms of actual time-consumption while preserving the quality of the results obtained by our proposed approach at a high level of agreement in comparison with the results produced by the other two approaches.


Asunto(s)
Modelos Teóricos , Programas Informáticos , Algoritmos
12.
J Microbiol Immunol Infect ; 47(3): 245-53, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24246191

RESUMEN

BACKGROUND: Although echinocandins have high in vitro antifungal efficacy according to prior reports, comparative studies on the clinical cure rates of anidulafungin, caspofungin, and micafungin in systemic candida infections have not yet been reported. METHODS: Interpretation of clinical and microbiological responses to anidulafungin, caspofungin, and micafungin in 109 cases of candidemia was done according to the published criteria. The clinical cure rates between patients treated with echinocandins and patients treated with fluconazole were also compared. The minimal inhibitory concentrations (MICs) of anidulafungin, caspofungin, micafungin, and fluconazole for these 109 blood isolates of candida were determined with the Clinical and Laboratory Standards Institute M27-A reference microdilution method. Logistic regression with forward selection was used to determine the important factors of prognosis with variables such as age, underlying diseases, acute physiology and chronic health evaluation (APACHE) III score, persistent candidemia, and antimicrobial therapy. RESULTS: Among the 109 cases of candidemia, 70 were treated with echinocandins, azoles, or amphotericin B for ≥7 days. The clinical cure rate of cases treated with antifungal agents adequately (≥7 days) and inadequately (<7 days) were 44/70 (62.9%) and 4/39 (10.2%), respectively, with significant difference (p < 0.0001). Clinical cure rates of anidulafungin, caspofungin, micafungin, and fluconazole were 18/30 (60.0%), 8/9 (88.9%), 5/7 (71.4%), and 9/18 (50%), respectively. The difference in APACHE III score between treatment success and failure cases was significant. The MIC50/MIC90 of anidulafungin, caspofungin, and micafungin for all Candida spp. were 0.03/1 µg/mL, 0.06/0.5 µg/mL, and 0.008/1 µg/mL, respectively. CONCLUSION: Adequate antifungal therapy and APACHE III score are both independent factors affecting the clinical outcome. The clinical cure rate of the echinocandins group was higher than that of the fluconazole group without significant difference. Although caspofungin had the best clinical cure rate in this study, there was no significant difference between the clinical cure rates among these three echinocandins. All Candida spp. were susceptible in vitro to these three echinocandins.


Asunto(s)
Antifúngicos/farmacología , Candidemia , Equinocandinas/farmacología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/uso terapéutico , Candida/efectos de los fármacos , Candidemia/tratamiento farmacológico , Candidemia/epidemiología , Candidemia/microbiología , Candidemia/mortalidad , Niño , Equinocandinas/uso terapéutico , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
13.
Opt Lett ; 39(18): 5467-70, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26466299

RESUMEN

The surface phonon polariton (SPhP) characteristics of hexagonal sapphire crystals with non-polar and semi-polar crystallographic planes are investigated. A formulation that considers the effects of crystal orientation is employed to calculate the SPhP dispersion curves of the samples. The SPhP dispersion curves indicate that the SPhP responses of sapphire crystals in non-polar and semi-polar orientations are directionally sensitive. Resonance frequencies and spectral strengths of the SPhP modes can be modulated simply by tuning the angular positions of the samples. The validity of the theoretical results is confirmed by the polarized infrared attenuated total reflection measurements.

14.
BMC Infect Dis ; 13: 163, 2013 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-23556473

RESUMEN

BACKGROUND: In 2003, nosocomial infections caused by vancomycin-resistant enterococci (VRE) occurred rarely in Taiwan. Between 2003 and 2010, however, the average prevalence of vancomycin resistance among enterococci spp. increased from 2% to 16% in community hospitals and from 3% to 21% in medical centers of Taiwan. We used molecular methods to investigate the epidemiology of VRE in a tertiary teaching hospital in Taiwan. METHODS: Between February 2009 and February 2011, rectal samples and infection site specimens were collected from all inpatients in the nephrology ward after patient consent was obtained. VRE strain types were determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). RESULTS: A total of 59 vanA gene-containing VRE isolates (1 per patient) were obtained; 24 originated from rectal sample surveillance of patients who exhibited no symptoms (22 Enterococcus faecium and 2 Enterococcus faecalis), and 35 had developed infections over 3 days after admission (32 E. faecium, 2 E. faecalis, and 1 Enterococcus durans). The 59 VRE isolates demonstrated vancomycin minimum inhibitory concentrations (MICs) of ≥256 µg/m. The MIC range for linezolid, tigecycline, and daptomycin was 0.25-1.5 µg/mL, 0.032-0.25 and 1-4 µg/mL, respectively. For 56 isolates, the MIC for teicoplanin was >8 µg/mL. The predominant types in the nephrology ward were MLST types 414, 78, and18 as well as PFGE types A, C, and D. CONCLUSION: VREs are endemic in nephrology wards. MLST 414 is the most predominant strain. The increase VRE prevalence is due to cross-transmission of VRE clones ST 414,78,18 by undetected VRE carriers. Because similar VRE STs had been reported in a different hospital of Taiwan, this finding may indicate inter-hospital VRE spread in Taiwan. Active surveillance and effective infection control policies are important controlling the spread of VRE in high risk hospital zones. All endemic VRE strains are resistant to teicoplanin but are sensitive to daptomycin, linezolid, and tigecycline.


Asunto(s)
Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Enterococcus/aislamiento & purificación , Infecciones por Bacterias Grampositivas/epidemiología , Resistencia a la Vancomicina , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Infección Hospitalaria/microbiología , Electroforesis en Gel de Campo Pulsado , Enfermedades Endémicas , Enterococcus/clasificación , Enterococcus/efectos de los fármacos , Enterococcus/genética , Femenino , Infecciones por Bacterias Grampositivas/microbiología , Hospitales de Enseñanza , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Taiwán/epidemiología , Centros de Atención Terciaria , Vancomicina/farmacología
15.
Diagn Microbiol Infect Dis ; 76(1): 86-92, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23420009

RESUMEN

Studies comparing adult community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) and community-onset healthcare-associated MRSA (COHCA MRSA bacteremia have not been available. From 1 January 2010 through 30 October 2010, a prospective observational program was conducted among all patients aged >16 years with positive Staphylococcus aureus blood cultures within 48 h after their arrival at the emergency department of our hospital. Clinical course of infection and infection foci of bacteremia were evaluated. Resistance to oxacillin was confirmed with the presence of mecA gene examined by polymerase chain reaction. Presence of TSST-1, PVL gene, SCCmec elements (I-V), mecA gene, and multilocus sequence typing were identified through methods described elsewhere. Univariate and multivariate analysis revealed that chronic renal failure was significantly more common in COHCA-MRSA than in CA-MRSA. In addition, APACHE III score was significantly higher in COHCA-MRSA than in CA-MRSA. Both the 7-day and 30-day mortality rates in COHCA-MRSA, 14.6% (7/48) and 29.2% (14/48), respectively, were higher than those in CA-MRSA without a significant difference. SCCmec II was more common in COHCA-MRSA, but SCCmecVT was more common in CA-MRSA. The majority of MRSA isolates belonged to ST59, ST239, and ST5. ST59 was significantly more common in CA-MRSA, while ST239 was nearly equally common in both CA-MRSA and COHCA-MRSA. SCCmec III and II isolates were the first and second most resistant to the antibiotics commonly used for S. aureus, whereas SCCmecVT isolates were the most susceptible to these antibiotics. We conclude that, although both CA-MRSA and COHCA-MRSA bacteremia had community onset, these 2 MRSA infections were different in underlying diseases, risk of mortality, SCCmec types, sequence types, and antimicrobial susceptibility. It is more appropriate to understand the MRSA pathogen and clinical features based on etiology and ST types than based on the location of disease onset. CA-MRSA and HCA-MRSA should be differentiated also based on etiology and ST types, in addition to location of acquisition.


Asunto(s)
Bacteriemia/microbiología , Bacteriemia/mortalidad , Infecciones Comunitarias Adquiridas/mortalidad , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Infecciones Comunitarias Adquiridas/microbiología , Farmacorresistencia Bacteriana Múltiple , Enterotoxinas/genética , Femenino , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Análisis Multivariante , Oxacilina/uso terapéutico , Proteínas de Unión a las Penicilinas , Estudios Prospectivos , Factores de Riesgo , Superantígenos/genética
16.
Head Neck ; 35(2): E49-51, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22422483

RESUMEN

BACKGROUND: Free tissue reconstruction after ablation of head and neck malignancy often requires extensive cervical manipulation, which may exacerbate preexisting cervical spondylosis and result in progression to cervical myelopathy. We present a rare case of postoperative quadriplegia caused by cervical spondylotic myelopathy after head and neck reconstruction. METHODS AND RESULTS: A 63-year-old man without a history of cervical spondylosis underwent resection of a gingivo-buccal squamous cell carcinoma with immediate reconstruction with free fibula osteocutaneous flap. On postoperative day 4, the patient was found to have quadriplegia. MRI demonstrated severe cervical myelopathy. Decompressive laminectomy was performed. The patient underwent an extensive rehabilitation program but only realized moderate improvement. CONCLUSION: Cervical spondylotic myelopathy is a rare but disastrous complication of head and neck surgery. We hypothesize that it is potentially avoidable with heightened awareness of this disease entity, preoperative identification of patients at risk, and prophylactic interventions


Asunto(s)
Disección del Cuello/efectos adversos , Procedimientos de Cirugía Plástica/efectos adversos , Cuadriplejía/cirugía , Enfermedades de la Médula Espinal/diagnóstico , Espondilosis/cirugía , Colgajos Quirúrgicos/efectos adversos , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Descompresión Quirúrgica/métodos , Descompresión Quirúrgica/rehabilitación , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Neoplasias de la Boca/cirugía , Disección del Cuello/métodos , Cuadriplejía/etiología , Enfermedades Raras , Procedimientos de Cirugía Plástica/métodos , Medición de Riesgo , Enfermedades de la Médula Espinal/cirugía , Espondilosis/diagnóstico , Resultado del Tratamiento
17.
J Clin Neurosci ; 20(1): 49-52, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23063497

RESUMEN

Decompressive craniectomy has been considered the most attractive option for surgical treatment of malignant middle cerebral artery (MCA) infarction. We retrospectively reviewed the clinical and radiological records of 78 patients with malignant MCA infarction who underwent decompressive craniectomy with dura augmentation over a 6-year period. Twenty-six patients had undergone additional anterior temporal resection during decompressive craniectomy. The overall mortality at 30 days after surgery was 25.6% while the mortality rate at 6 months after surgery was 30.8%. At 6 months after surgery, 30.8% of the patients were considered to have good outcomes, while 69.2% had a poor outcome (16.7% suffered from severe disability, 21.8% remained in a vegetative state, and 30.8% died). Ipsilateral surgery was performed on 48 patients with infarction on the dominant side and on 30 patients with lesions on the non-dominant side. No significant difference was noted between these two groups at the 30-day mortality rate. Although no patient with an infarction on the dominant side recovered effective verbal ability during the 6 months of follow-up, there was no significant difference between the two groups in clinical outcome at 6 months after surgery. The 30-day survival rate in the 26 patients who underwent additional anterior temporal lobectomy was significantly higher (84.6%) than that in patients who underwent decompressive craniectomy and duroplasty only (69.2%) (p<0.05). However, in patients who survived, this additional procedure does not appear to improve the functional outcome.


Asunto(s)
Descompresión Quirúrgica/métodos , Infarto de la Arteria Cerebral Media/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Edema Encefálico/etiología , Edema Encefálico/prevención & control , Infarto Encefálico/etiología , Infarto Encefálico/prevención & control , Distribución de Chi-Cuadrado , Femenino , Estudios de Seguimiento , Escala de Coma de Glasgow , Humanos , Infarto de la Arteria Cerebral Media/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
18.
J Neurosurg ; 117(2): 348-53, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22631693

RESUMEN

OBJECT: Liver cirrhosis was identified as an independent predictor of poor outcomes in patients suffering trauma and in those undergoing major surgeries. The aim of this study was to report the authors' experiences treating patients with cirrhosis who undergo brain surgeries. METHODS: Between 2004 and 2009, 121 consecutive patients with cirrhosis underwent 144 brain procedures. Patients were categorized as Child-Turcotte-Pugh (referred to as "Child") Class A, B, or C. The patient profiles, including the severity of cirrhosis, reason for surgery, complications, and prognosis factors, were analyzed. RESULTS: In this retrospective study, the overall surgical complication rate for patients with cirrhosis was 52.1% and the mortality rate was 24.3%. For patients with acute traumatic brain injury (TBI), the complication, rebleeding, and mortality rates reached 84.4%, 68.8%, and 37.5%, respectively. Surgery for TBI was a significant risk factor for postoperative complications (p = 0.0002) and postoperative hemorrhage (p < 0.0001). Otherwise, according to the Child classification, the complication rate increased in a stepwise fashion from 38.7% to 60% to 84.2%, the rebleeding rate from 29.3% to 48.0% to 63.2%, and the mortality rate from 5.3% to 38% to 63.2% for Child A, B, and C, respectively. The Child classification was associated with higher risk of complications-Child B vs A OR 2.84 (95% CI 1.28-6.29), Child C vs A OR 5.39 (95% CI 1.32-22.02). It was also associated with risk of death-Child C vs A OR 30.43 (95% CI 7.71-120.02), Child B vs A OR 10.88 (95% CI 3.42-34.63). CONCLUSIONS: Liver cirrhosis is a poor comorbidity factor for brain surgery. The authors' results suggest that the Child classification used independently is a poor prognostic factor; in addition, grave outcomes were observed in patients with TBI.


Asunto(s)
Encefalopatías/cirugía , Lesiones Encefálicas/cirugía , Neoplasias Encefálicas/cirugía , Cirrosis Hepática/complicaciones , Cirrosis Hepática/fisiopatología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/fisiopatología , Adulto , Anciano , Encefalopatías/mortalidad , Lesiones Encefálicas/mortalidad , Neoplasias Encefálicas/mortalidad , Femenino , Mortalidad Hospitalaria , Humanos , Cirrosis Hepática/mortalidad , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Hemorragia Posoperatoria/mortalidad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
19.
J Microbiol Immunol Infect ; 45(4): 276-80, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22444547

RESUMEN

BACKGROUND: Scabies is a global problem. Transmission of scabies is usually due to direct or indirect contact. Delay in diagnosis may result in the spread of the scabies mite. Prompt diagnosis and treatment are important. METHODS: In this study, we collected data from 52 scabies patients and analyzed the risk factors for scabies with the case-control method. RESULTS: Our study has revealed that the patients who were bedridden [odds ratio (OR) 6.72, p < 0.0001], living in a nursing home (OR 9.89, p < 0.0001), had a higher clinical severity status before admission (OR 1.25, p < 0.0001), and a catheter inserted (including nasogastric tube, Foley catheter, Port-A, or Hickman catheter) (OR 9.05, p < 0.0001) were significantly more likely to acquire scabies infection. CONCLUSION: To prevent scabies, proper management of the nursing home setting, including adequate cleaning of the contaminated clothing, bedding and equipment, in combination with treating all suspected scabies patients, and contact isolation are important and necessary.


Asunto(s)
Escabiosis/diagnóstico , Escabiosis/epidemiología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Catéteres/efectos adversos , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/prevención & control , Femenino , Hospitalización , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Casas de Salud , Oportunidad Relativa , Cuarentena/métodos , Factores de Riesgo , Escabiosis/tratamiento farmacológico , Escabiosis/prevención & control , Taiwán/epidemiología
20.
Chang Gung Med J ; 34(6): 580-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22196060

RESUMEN

BACKGROUND: In recent years, there has been a rapid worldwide emergence of multidrugresistant (MDR) pathogens, especially in cases of nosocomial infections. This study assesses the in vitro activities of ampicillin/sulbactam, cefpirome, colistin, daptomycin, ertapenem, meropenem, teicoplanin, tigecycline and vancomycin against 208 aerobic bacterial pathogens that caused 197 nosocomial infections in 184 patients. METHODS: Antimicrobial susceptibility was evaluated by Etest. Broth dilution method was utilized in tigecycline susceptibility testing. RESULTS: Most (140/208, 67%) of the isolates were facultative Gram-negative bacilli. Of the 31 oxacillin-resistant S. aureus (ORSA) isolates, 16 were susceptible to daptomycin (16/31, 51.6%) according to the breakpoint ≤ 1 µg/ml. All 31 ORSA isolates were susceptible to teicoplanin, and vancomycin but MICs of vancomycin for all 31 ORSA isolates were ≥ 1 µg/ml. Of the 21 isolates of A. baumannii that were multiple-drug-resistant, 19 isolates (19/21, 90%) were susceptible to colistin and 18 isolates (18/21, 86%) sensitive to tigecycline. Of the 22 isolates of E. coli with extended-spectrum beta-lactamase (ESBL), the most susceptible antimicrobial agent were colistin (20/22, 91%), ertapenem (21/22, 96%), meropenem and tigecycline (22/22, 100%). Of the 11 isolates of P. aeruginosa, 6 isolates were susceptible to colistin (6/11, 55%) and all isolates were susceptible to meropenem (11/11, 100%). CONCLUSION: For nosocomial infections caused by MDR-Acinetobacter baumannii, colistin and tigecycline are usually susceptible according to the result of this study. For nosocomial infections caused by ORSA, ORSA has reduced susceptibility to vancomycin, teicoplanin and daptomycin. For MDR-P. aeruginosa, further study is needed.


Asunto(s)
Antibacterianos/farmacología , Bacterias Aerobias/efectos de los fármacos , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Humanos
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