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1.
Antimicrob Agents Chemother ; 65(11): e0067321, 2021 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-34370577

RESUMEN

Q fever, caused by the intracellular pathogen Coxiella burnetii, is traditionally treated using tetracycline antibiotics, such as doxycycline. Doxycycline is often poorly tolerated, and antibiotic-resistant strains have been isolated. In this study, we have evaluated a panel of antibiotics (doxycycline, ciprofloxacin, levofloxacin, and co-trimoxazole) against C. burnetii using in vitro methods (determination of MIC using liquid and solid media; efficacy assessment in a THP cell infection model) and in vivo methods (wax moth larvae and mouse models of infection). In addition, the schedule for antibiotic treatment has been evaluated, with therapy initiated at 24 h pre- or postchallenge. Both doxycycline and levofloxacin limited overt clinical signs during treatment in the AJ mouse model of aerosol infection, but further studies are required to investigate the possibility of disease relapse or incomplete bacterial clearance after the antibiotics are stopped. Levofloxacin was well tolerated and therefore warrants further investigation as an alternative to the current recommended treatment with doxycycline.


Asunto(s)
Coxiella burnetii , Fiebre Q , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ciprofloxacina/farmacología , Doxiciclina , Levofloxacino , Ratones , Fiebre Q/tratamiento farmacológico , Combinación Trimetoprim y Sulfametoxazol
2.
Microbiology (Reading) ; 160(Pt 6): 1175-1181, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24677067

RESUMEN

Coxiella burnetii is a Gram-negative intracellular bacterium and is the causative agent of the zoonotic disease Q fever. Several rodent and non-human primate models of virulent phase I C. burnetii [Nine Mile (NM)I] have been developed, and have been used to determine the efficacy of antibiotics and vaccine candidates. However, there are several advantages to using insect models to study host-microbe interactions, such as reduced animal use, lowered cost and ease of manipulation in high containment. In addition, many laboratories use the avirulent phase II C. burnetii clone (NMII) to study cellular interactions and identify novel virulence determinants using genetic manipulation. We report that larvae of the greater wax moth, Galleria mellonella, were susceptible to infection with both C. burnetii NMI and NMII. Following subcutaneous infection, we report that intracellular bacteria were present within haemocytes and that larval death occurred in a dose-dependent manner. Additionally, we have used the model to characterize the role of the type 4 secretion system in C. burnetii NMII and to determine antibiotic efficacy in a non-mammalian model of disease.


Asunto(s)
Coxiella burnetii/crecimiento & desarrollo , Lepidópteros/microbiología , Modelos Animales , Fiebre Q , Animales , Coxiella burnetii/patogenicidad , Hemocitos/microbiología , Interacciones Huésped-Patógeno , Larva/microbiología , Análisis de Supervivencia , Virulencia , Factores de Virulencia/metabolismo
3.
Microb Pathog ; 63: 16-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23707360

RESUMEN

CpG DNA is a potent activator of the innate immune system. Here the protective effects of CpG DNA are assessed against the facultative intracellular pathogen Francisella tularensis. Dosing of mice with CpG DNA provided protection against disease caused by F. tularensis subsp. holarctica live vaccine strain (LVS) but did not protect against the fully virulent F. tularensis subsp holarctica strain HN63. Similarly, in vitro studies in J774A murine macrophage-like cells demonstrated that stimulation with CpG DNA enables control of intracellular replication of LVS but not HN63. These data confirm findings that CpG DNA may have limited efficacy in providing protection against fully virulent strains of F. tularensis and also suggest that in vitro assays may be useful for the evaluation of novel treatments for virulent F. tularensis.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Vacunas Bacterianas/administración & dosificación , Vacunas Bacterianas/inmunología , Francisella tularensis/inmunología , Oligodesoxirribonucleótidos/administración & dosificación , Tularemia/prevención & control , Animales , Línea Celular , Citosol/microbiología , Modelos Animales de Enfermedad , Macrófagos/inmunología , Macrófagos/microbiología , Ratones , Análisis de Supervivencia , Tularemia/inmunología
4.
Antibiotics (Basel) ; 12(5)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37237817

RESUMEN

The timing of the initiation of antibiotic treatment has been shown to impact the clinical outcome of many bacterial infections, including Q fever. Delayed, suboptimal or incorrect antibiotic treatment has been shown to result in poor prognosis, resulting in the progression of acute disease to long-term chronic sequalae. Therefore, there is a requirement to identify an optimal, effective therapeutic regimen to treat acute Q fever. In the study, the efficacies of different doxycycline monohydrate regimens (pre-exposure prophylaxis, post-exposure prophylaxis or treatment at symptom onset or resolution) were evaluated in an inhalational murine model of Q fever. Different treatment lengths (7 or 14 days) were also evaluated. Clinical signs and weight loss were monitored during infection and mice were euthanized at different time points to characterize bacterial colonization in the lungs and the dissemination of bacteria to other tissues including the spleen, brain, testes, bone marrow and adipose. Post-exposure prophylaxis or doxycycline treatment starting at symptoms onset reduced clinical signs, and also delayed the systemic clearance of viable bacteria from key tissues. Effective clearance was dependent on the development of an adaptive immune response, but also driven by sufficient bacterial activity to maintain an active immune response. Pre-exposure prophylaxis or post-exposure treatment at the resolution of clinical signs did not improve outcomes. These are the first studies to experimentally evaluate different doxycycline treatment regimens for Q fever and illustrate the need to explore the efficacy of other novel antibiotics.

5.
Respir Care ; 57(12): 2032-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22709916

RESUMEN

BACKGROUND: Few published data exist for adherence rates to spirometry acceptability and repeatability criteria in clinical respiratory laboratories. This study quantified adherence levels in this setting and observed changes in adherence levels as a result of feedback and ongoing training. METHODS: Two tertiary hospital-based, lung function laboratories (L1 and L2) participated. Approximately 100 consecutive, FVC spirometry sessions were reviewed for each year from 2004 to 2008 at L1 and for years 2004 and 2008 at L2. Each spirometric effort and session was interrogated for adherence to the acceptability and repeatability criteria of international spirometry standards of the time. Feedback of audit results and refresher training were provided at L1 throughout the study; in addition, a quality rating scale was implemented in 2006. No formal feedback or follow-up training was provided at L2. RESULTS: We reviewed 707 test sessions over the 5 years. There was no difference in adherence rates to acceptability and repeatability criteria between sites in 2004 (L1 61%, L2 59%, P = .89). There was, however, a significant difference between sites in 2008 (L1 92%, L2 65%, P < .001). No difference was seen at L2 between 2004 and 2008 (P = .26), while L1 experienced a significant increase in adherence levels between 2004 and 2008 (61% to 92% P < .001). CONCLUSIONS: Clinical respiratory laboratories met published spirometry acceptability and repeatability criteria only 60% of the time in the first audit period. This improved with regular review, feedback, and implementation of a rating scale. Auditing of spirometry quality, feedback, and implementation of test rating scales need to be incorporated as an integral component of laboratory quality assurance programs to improve adherence to international acceptability and repeatability criteria.


Asunto(s)
Laboratorios de Hospital/normas , Espirometría/normas , Adulto , Anciano , Femenino , Humanos , Capacitación en Servicio , Masculino , Auditoría Médica , Persona de Mediana Edad , Competencia Profesional , Mejoramiento de la Calidad , Terapia Respiratoria/educación , Servicio de Terapia Respiratoria en Hospital/normas
6.
BMJ Mil Health ; 168(6): 462-466, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36109067

RESUMEN

INTRODUCTION: Disaster management is the process of preparing, responding and recovering to an emergency whether that be natural or man-made. It is a time-consuming, resource-heavy process with the aim of reducing the risk of certain events and, where not possible, reducing the impact of said disaster, ensuring that the risks have been identified and appropriate rescue and recovery plan is in place. METHODS: We carried out a thorough literature search on the complications of hot, cold and altitude environments in disaster management and distilled the learnings into this article. RESULTS: The incidence of disasters of natural, man-made and complex origin is likely to continue increasing as global temperatures continue to rise. CONCLUSION: Disaster management in the extreme environments of hot, cold and high altitude is fraught with unique challenges, especially around the physiological response of rescuers, resource constraints and logistics. Recognising these challenges is an important aspect of planning and preparation for disaster management in these environments.


Asunto(s)
Planificación en Desastres , Desastres , Humanos , Altitud
7.
BMJ Mil Health ; 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35878971

RESUMEN

BACKGROUND: In the face of the COVID-19 pandemic, the Defence Science and Technology Laboratory (Dstl) and Defence Pathology combined to form the Defence Clinical Lab (DCL), an accredited (ISO/IEC 17025:2017) high-throughput SARS-CoV-2 PCR screening capability for military personnel. LABORATORY STRUCTURE AND RESOURCE: The DCL was modular in organisation, with laboratory modules and supporting functions combining to provide the accredited SARS-CoV-2 (envelope (E)-gene) PCR assay. The DCL was resourced by Dstl scientists and military clinicians and biomedical scientists. LABORATORY RESULTS: Over 12 months of operation, the DCL was open on 289 days and tested over 72 000 samples. Six hundred military SARS-CoV-2-positive results were reported with a median E-gene quantitation cycle (Cq) value of 30.44. The lowest Cq value for a positive result observed was 11.20. Only 64 samples (0.09%) were voided due to assay inhibition after processing started. CONCLUSIONS: Through a sustained effort and despite various operational issues, the collaboration between Dstl scientific expertise and Defence Pathology clinical expertise provided the UK military with an accredited high-throughput SARS-CoV-2 PCR test capability at the height of the COVID-19 pandemic. The DCL helped facilitate military training and operational deployments contributing to the maintenance of UK military capability. In offering a bespoke capability, including features such as testing samples in unit batches and oversight by military consultant microbiologists, the DCL provided additional benefits to the UK Ministry of Defence that were potentially not available from other SARS-CoV-2 PCR laboratories. The links between Dstl and Defence Pathology have also been strengthened, benefitting future research activities and operational responses.

8.
Perfusion ; 26(2): 79-81, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21173035

RESUMEN

We report a case of reduced cerebral oxygenation which had the possibility of leading to an adverse outcome if it had not been detected by the routine use of cerebral oximetry. This case study illustrates that an inadvertent re-adjustment of a single-stage venous cannula within the superior vena cava resulted only in the cerebral oximetry device alerting to a potential problem. All other monitoring devices remained within standard operating parameters, with no deviation throughout the duration of the incident.


Asunto(s)
Encéfalo/metabolismo , Procedimientos Quirúrgicos Cardíacos/métodos , Oximetría/métodos , Oxígeno/metabolismo , Anciano , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Humanos
9.
Front Microbiol ; 12: 760698, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34917048

RESUMEN

Finafloxacin is a novel fluoroquinolone with optimal antibacterial activity in low pH environments, therefore offering a therapeutic advantage over some traditional antibiotics, in treating bacterial infections associated with acidic foci. Coxiella burnetii, the causative agent of Q fever, is a bacterium which resides and replicates in acidic intracellular parasitic vacuoles. The efficacy of finafloxacin was evaluated in vivo using the A/J mouse model of inhalational Q fever and was compared to doxycycline, the standard treatment for this infection and ciprofloxacin, a comparator fluoroquinolone. Finafloxacin reduced the severity of the clinical signs of infection and weight loss associated with Q fever, but did not reduce the level of bacterial colonization in tissues compared to doxycycline or ciprofloxacin. However, histopathological analysis suggested that treatment with finafloxacin reduced tissue damage associated with C. burnetii infection. In addition, we report for the first time, the use of viable counts on axenic media to evaluate antibiotic efficacy in vivo.

10.
Infect Immun ; 78(10): 4356-62, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20660611

RESUMEN

Yersinia pestis is the causative agent of plague, a rapidly fatal infectious disease that has not been eradicated worldwide. The capsular Caf1 protein of Y. pestis is a protective antigen under development as a recombinant vaccine. However, little is known about the specificity of human T-cell responses for Caf1. We characterized CD4 T-cell epitopes of Caf1 in "humanized" HLA-DR1 transgenic mice lacking endogenous major histocompatibility complex class II molecules. Mice were immunized with Caf1 or each of a complete set of overlapping synthetic peptides, and CD4 T-cell immunity was measured with respect to proliferative and gamma interferon T-cell responses and recognition by a panel of T-cell hybridomas, as well as direct determination of binding affinities of Caf1 peptides to purified HLA-DR molecules. Although a number of DR1-restricted epitopes were identified following Caf1 immunization, the response was biased toward a single immunodominant epitope near the C terminus of Caf1. In addition, potential promiscuous epitopes, including the immunodominant epitope, were identified by their ability to bind multiple common HLA alleles, with implications for the generation of multivalent vaccines against plague for use in humans.


Asunto(s)
Proteínas Bacterianas/inmunología , Linfocitos T CD4-Positivos/inmunología , Antígenos HLA/metabolismo , Antígeno HLA-DR1/inmunología , Yersinia pestis/inmunología , Animales , Epítopos , Antígenos HLA/genética , Humanos , Ratones , Ratones Transgénicos , Unión Proteica
11.
Ann R Coll Surg Engl ; 102(9): 693-696, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32538118

RESUMEN

INTRODUCTION: The incidence of delayed gastric emptying (DGE) following oesophagogastrectomy with gastric conduit reconstruction is reported to be between 1.7% and 50%. This variation is due to differing practices of intraoperative pylorus drainage procedures, which increase the risk of postoperative biliary reflux and dumping syndrome, resulting in significant morbidity. The aim of our study was to establish rates of DGE in people undergoing oesophagogastrectomy without routine intraoperative drainage procedures, and to evaluate outcomes of postoperative endoscopically administered Botulinum toxin into the pylorus (EBP) for people with DGE resistant to systemic pharmacological treatment. METHODS: All patients undergoing oesophagogastrectomy between 1 January 2016 and 31 March 2018 at our unit were included. No intraoperative pyloric drainage procedures were performed, and DGE resistant to systemic pharmacotherapy was managed with EBP. RESULTS: Ninety-seven patients were included. Postoperatively, 29 patients (30%) were diagnosed with DGE resistant to pharmacotherapy. Of these, 16 (16.5%) were diagnosed within 30 days of surgery. The median pre-procedure nasogastric tube aspirate was 780ml; following EBP, this fell to 125ml (p<0.001). Median delay from surgery to EBP in this cohort was 13 days (IQR 7-16 days). Six patients required a second course of EBP, with 100% successful resolution of DGE before discharge. There were no procedural complications. CONCLUSIONS: This is the largest series of patients without routine intraoperative drainage procedures. Only 30% of patients developed DGE resistant to pharmacotherapy, which was managed safely with EBP in the postoperative period, thus minimising the risk of biliary reflux in people who would otherwise be at risk following prophylactic pylorus drainage procedures.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Esofagectomía/efectos adversos , Gastrectomía/efectos adversos , Gastroparesia/tratamiento farmacológico , Gastroscopía , Píloro/efectos de los fármacos , Toxinas Botulínicas Tipo A/administración & dosificación , Neoplasias Esofágicas/cirugía , Esofagectomía/métodos , Femenino , Gastrectomía/métodos , Gastroparesia/etiología , Gastroscopía/métodos , Humanos , Masculino , Píloro/fisiopatología , Neoplasias Gástricas/cirugía
12.
Science ; 252(5007): 851-3, 1991 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-1709304

RESUMEN

NMDA (N-methyl-D-aspartate) receptors and non-NMDA receptors represent the two major classes of ion channel-linked glutamate receptors. Unlike the NMDA receptor channels, non-NMDA receptor channels have usually been thought to conduct monovalent cations only. Non-NMDA receptor ion channels that can be gated by kainic acid (KA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) are formed by the glutamate receptor subunits GluR1, GluR2, and GluR3. These subunits were expressed in various combinations in Xenopus oocytes so that their permeability to divalent cations could be studied. At physiological resting potentials, KA and AMPA elicited inward calcium currents in oocytes expressing GluR1, GluR3, and GluR1 plus GluR3. In contrast, oocytes expressing GluR1 plus GluR2 or GluR3 plus GluR2 showed no such permeability. Thus, in neurons expressing certain KA-AMPA receptor subunits, glutamate may trigger calcium-dependent intracellular events by activating non-NMDA receptors.


Asunto(s)
Calcio/farmacocinética , Ácido Iboténico/análogos & derivados , Activación del Canal Iónico/efectos de los fármacos , Canales Iónicos/metabolismo , Ácido Kaínico/farmacología , Receptores de Neurotransmisores/química , Animales , Ácido Iboténico/farmacología , Potenciales de la Membrana , Receptores de Glutamato , Sodio/farmacocinética , Xenopus , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico
13.
Science ; 268(5212): 873-6, 1995 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-7754371

RESUMEN

The function of the N-methyl-D-aspartate (NMDA)-preferring glutamate receptor can be regulated by extracellular pH, a process that may be important during ischemia in the brain or during seizures. Protons inhibit NMDA receptor function by 50 percent at pH 7.3 through interactions with the NR1 subunit, and both polyamines and NR1 exon 5 potentiate receptor function through relief of the tonic proton inhibition present at physiological pH. A single amino acid (lysine 211) was identified that mediates the effects of exon 5 in the rat brain. Electroneutral substitutions at this position restored pH sensitivity and, consequently, polyamine relief of tonic inhibition. This effect, together with the structural similarities between polyamines and the surface loop encoded by exon 5, suggest that exon 5 may act as a tethered pH-sensitive constitutive modulator of NMDA receptor function.


Asunto(s)
Empalme Alternativo , Protones , Receptores de N-Metil-D-Aspartato/fisiología , Espermina/farmacología , Secuencia de Aminoácidos , Animales , Línea Celular , Exones , Concentración de Iones de Hidrógeno , Lisina/fisiología , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Oocitos , Estructura Secundaria de Proteína , Ratas , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Xenopus
14.
Science ; 249(4972): 1033-7, 1990 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-2168579

RESUMEN

Three closely related genes, GluR1, GluR2, and GluR3, encode receptor subunits for the excitatory neurotransmitter glutamate. The proteins encoded by the individual genes form homomeric ion channels in Xenopus oocytes that are sensitive to glutamatergic agonists such as kainate and quisqualate but not to N-methyl-D-aspartate, indicating that binding sites for kainate and quisqualate exist on single receptor polypeptides. In addition, kainate-evoked conductances are potentiated in oocytes expressing two or more of the cloned receptor subunits. Electrophysiological responses obtained with certain subunit combinations show agonist profiles and current-voltage relations that are similar to those obtained in vivo. Finally, in situ hybridization histochemistry reveals that these genes are transcribed in shared neuroanatomical loci. Thus, as with gamma-aminobutyric acid, glycine, and nicotinic acetylcholine receptors, native kainate-quisqualate-sensitive glutamate receptors form a family of heteromeric proteins.


Asunto(s)
Familia de Multigenes , Receptores de Neurotransmisores/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Expresión Génica , Glutamatos/metabolismo , Hipocampo/metabolismo , Cinética , Sustancias Macromoleculares , Potenciales de la Membrana , Datos de Secuencia Molecular , Oocitos/fisiología , Ratas , Receptores de Glutamato , Receptores de Neurotransmisores/fisiología , Homología de Secuencia de Ácido Nucleico , Transcripción Genética
15.
Arch Virol ; 154(11): 1847-50, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19841859

RESUMEN

In August 2007, European bat lyssavirus type 2 (EBLV-2) was isolated from a Daubenton's bat found at Stokesay Castle. In September 2008, another bat from the same vicinity of Stokesay Castle also tested positive for EBLV-2. This is the first occurrence of repeated detection of EBLV-2 from a single site. Here, we report the detection of low levels of viral RNA in various bat organs by qRT-PCR and detection of viral antigen by immunohistochemistry. We also report sequence data from both cases and compare data with those derived from other EBLV-2 isolations in the UK.


Asunto(s)
Quirópteros , Lyssavirus/clasificación , Lyssavirus/aislamiento & purificación , Infecciones por Rhabdoviridae/veterinaria , Animales , Femenino , Humanos , Lyssavirus/genética , Masculino , Filogenia , Infecciones por Rhabdoviridae/epidemiología , Infecciones por Rhabdoviridae/virología , Reino Unido/epidemiología
16.
Front Microbiol ; 10: 1552, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31379760

RESUMEN

Historically, disease progression in animal models of Q fever has been carried out using PCR to monitor the presence of Coxiella burnetii DNA in the host. However, the colonization and dissemination of other bacterial infections in animal models are tracked using viable counts, enabling an accurate assessment of viable bacterial load within tissues. Following recent advances in the culture methods, it has become possible to do the same with C. burnetii. Here we compare and contrast the different information gained by using PCR or viable counts to study this disease. Viable bacteria were cleared from organs much faster than previously reported when assessed by bacterial DNA, but weight loss and clinical signs improved while animals were still heavily infected.

17.
Neuron ; 13(6): 1345-57, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7527641

RESUMEN

By exchanging portions of the AMPA receptor subunit GluR3 and the kainate receptor subunit GluR6, we have identified two discontinuous segments of approximately 150 amino acid residues each that control the agonist pharmacology of these glutamate receptors. The first segment (S1) is adjacent and N-terminal to the putative transmembrane domain 1 (TM1), whereas the second segment (S2) is located between the putative TM3 and TM4. Only the simultaneous exchange of S1 and S2 converts the pharmacological profile of the recipient to that of the donor subunit. The two segments identified in this study share sequence similarities with the ligand-binding site of several bacterial periplasmic amino acid-binding proteins. Based on the X-ray structure of these proteins, we propose a model for the glutamate-binding site of ionotropic glutamate receptors.


Asunto(s)
Proteínas Bacterianas , Receptores de Glutamato/química , Secuencia de Aminoácidos , Animales , Sitios de Unión , Proteínas Portadoras/química , Simulación por Computador , Electrofisiología , Glutamatos/farmacología , Células HeLa , Humanos , Técnicas In Vitro , Ácido Kaínico/análogos & derivados , Ácido Kaínico/farmacología , Ligandos , Modelos Moleculares , Datos de Secuencia Molecular , Oocitos , Ácido Quiscuálico/farmacología , Proteínas Recombinantes de Fusión , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transfección , Xenopus laevis , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/farmacología
18.
Bioinformatics ; 23(13): i508-18, 2007 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-17646338

RESUMEN

MOTIVATION: An important application of protein microarray data analysis is identifying a serodiagnostic antigen set that can reliably detect patterns and classify antigen expression profiles. This work addresses this problem using antibody responses to protein markers measured by a novel high-throughput microarray technology. The findings from this study have direct relevance to rapid, broad-based diagnostic and vaccine development. RESULTS: Protein microarray chips are probed with sera from individuals infected with the bacteria Francisella tularensis, a category A biodefense pathogen. A two-step approach to the diagnostic process is presented (1) feature (antigen) selection and (2) classification using antigen response measurements obtained from F.tularensis microarrays (244 antigens, 46 infected and 54 healthy human sera measurements). To select antigens, a ranking scheme based on the identification of significant immune responses and differential expression analysis is described. Classification methods including k-nearest neighbors, support vector machines (SVM) and k-Means clustering are applied to training data using selected antigen sets of various sizes. SVM based models yield prediction accuracy rates in the range of approximately 90% on validation data, when antigen set sizes are between 25 and 50. These results strongly indicate that the top-ranked antigens can be considered high-priority candidates for diagnostic development. AVAILABILITY: All software programs are written in R and available at http://www.igb.uci.edu/index.php?page=tools and at http://www.r-project.org. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Algoritmos , Antígenos Bacterianos/sangre , Inteligencia Artificial , Francisella tularensis/inmunología , Reconocimiento de Normas Patrones Automatizadas/métodos , Análisis por Matrices de Proteínas/métodos , Pruebas Serológicas/métodos , Humanos , Sensibilidad y Especificidad
19.
Br J Surg ; 95(12): 1506-11, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18991295

RESUMEN

BACKGROUND: Patients with duodenal polyps are at risk of duodenal cancer. Pancreas-preserving total duodenectomy (PPTD) is an alternative to partial pancreatoduodenectomy. METHODS: Twelve patients (seven men and five women) with a median age of 59 (interquartile range (i.q.r.) 50-67) years underwent PPTD for large (over 20 mm) solitary polyps or multiple (more than three) duodenal polyps confined to the muscularis propria on endoscopic ultrasonography. RESULTS: Median hospital stay was 21 (i.q.r. 10-36) days with no deaths and no blood transfusion. Six patients developed postoperative complications, one requiring reoperation. Histology demonstrated gastrointestinal stromal tumour in three patients, low-grade dysplasia in one, moderate-grade dysplasia in eight and duodenal intramucosal adenocarcinoma in one. During a median follow-up of 20 (i.q.r. 8-41) months one patient experienced recurrent acute pancreatitis (due to hypertriglyceridaemia) and one developed a jejunal adenocarcinoma in the neoduodenum. CONCLUSION: The morbidity of PPTD is similar to that of partial pancreatoduodenectomy, but PPTD preserves the whole pancreas and reduces the number of anastomoses.


Asunto(s)
Enfermedades Duodenales/cirugía , Pólipos Intestinales/cirugía , Pancreaticoduodenectomía/métodos , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Prospectivos
20.
Aust Vet J ; 86(6): 242-5, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18498563

RESUMEN

OBJECTIVE: To survey free-living platypuses for evidence of Leptospira interrogans. METHODS: A serological study of Leptospira antibodies was carried out on 21 platypuses captured between May and October 2001 in the Wollondilly River 200 km south of Sydney, New South Wales. RESULTS: Positive reactions, all to the L Hardjo serovar, were seen in 14 (66%) of the captured animals, with adult males showing a higher prevalence of antibodies than adult females. Several individual platypuses showed a high titre of L Hardjo antibodies, and some animals demonstrated cross-reactions to the serovars L Medanensis and L Kremastos. CONCLUSION: The serological findings demonstrate that these animals are constantly exposed to infection with Leptospira in their environment, but it is not known if platypuses suffer from clinical leptospirosis or if they mount an immune response, but are unaffected by the bacteria. The prevalence of Leptospira infection among the platypus population could not be precisely estimated because of the unknown number of individuals inhabiting the Wollondilly River inside the survey property. Domestic livestock, mostly cattle, may be the major source of Leptospira infection. The effects of this disease on population dynamics and on reproduction in wild platypuses are not well understood. The role of other wildlife in the transmission and maintenance of Leptospira in the environment is unknown.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Leptospira interrogans/inmunología , Leptospirosis/veterinaria , Ornitorrinco/microbiología , Animales , Animales Salvajes , Reacciones Cruzadas , Femenino , Leptospirosis/epidemiología , Masculino , Nueva Gales del Sur/epidemiología , Estaciones del Año , Estudios Seroepidemiológicos , Factores Sexuales , Especificidad de la Especie
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