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1.
Acta Paediatr ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377490

RESUMEN

AIM: To determine whether the use of less-invasive surfactant administration (LISA) had changed between 2018 and 2024. METHODS: An online questionnaire was sent to all 191 neonatal units between June 2023 and May 2024. One consultant from each neonatal unit was randomly selected. Follow-up was done by telephone (middle-grade doctor grade and above or alternatively to Advanced Neonatal Nurse Practitioners) for the non-responders. RESULTS: Response rate was 100%from 191 units neonatal units. LISA was used in 134 (70%) neonatal units in 2024 compared to 35 (18.7%) units in 2018 (p < 0.001). The reason why LISA was not performed was lack of experience/training (51%) or not having a standardised practice/guideline (49%). LISA in the delivery suite (DS) had increased from 2% in 2018 to 16% in 2024, and the use of video laryngoscope for LISA is becoming standard of practice. The oxygen requirement criteria for the use of LISA in both the DS and on neonatal unit had reduced to FiO2 of 0.3 or more. CONCLUSION: The uptake of LISA had increased in the United Kingdom. There is greater use of LISA in the DS. Lack of training and expertise were the major limiting factors for LISA not being performed.

2.
Arch Virol ; 163(7): 1927-1931, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29532267

RESUMEN

Cytomegalovirus (CMV) typically causes gastrointestinal infections in immunocompetent patients. Colonic perforations secondary to CMV are exceeding rare. We describe a 88-year-old male presenting with a week-long history of intractable abdominal discomfort, bloating, nausea and diarrhea. Flexible sigmoidoscopy revealed significant ulceration with yellowish slough. Emergency surgery was performed subsequently in view of multiple perforations in the rectosigmoid junction. CMV gastrointestinal infections demonstrated an ischemic process secondary to vasculitis, which accelerated the pathway to colonic perforation. CMV gastrointestinal infection should be considered as a differential diagnosis in patients with colonoscopy findings similar to ischemic colitis and Clostridium difficile infections.


Asunto(s)
Colitis Isquémica/complicaciones , Infecciones por Citomegalovirus/complicaciones , Perforación Intestinal/complicaciones , Perforación Intestinal/etiología , Anciano de 80 o más Años , Colitis Isquémica/diagnóstico , Colitis Isquémica/virología , Colonoscopía , Citomegalovirus/aislamiento & purificación , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/patología , Infecciones por Citomegalovirus/virología , Diagnóstico Diferencial , Diarrea/virología , Humanos , Masculino , Proctocolitis/complicaciones , Proctocolitis/diagnóstico , Proctocolitis/patología , Proctocolitis/virología , Sigmoidoscopía , Vasculitis/virología
3.
Surg Endosc ; 30(5): 1796-803, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26198158

RESUMEN

BACKGROUND: Higher adenoma detection rates are associated with decreased risks for subsequent colorectal cancers. Studies have suggested that adenoma detection rate (ADR) may be affected by timing of colonoscopy due to endoscopist fatigue later in the day. The aim of our study is to assess the influence of the timing variables on ADR. METHODS: Univariate analysis and multivariate logistic regression analysis were performed on a prospective colonoscopy database, comparing ADR for colonoscopies performed in the morning shift (AM) and in the afternoon shift (PM) over a 1-year period. Each shift lasted 4 h. Only elective outpatient completed colonoscopies with adequate bowel preparation, performed by four certified staff endoscopists, were included. Surveillance colonoscopies for cancers were excluded. ADR was defined as the detection of at least one histologically confirmed polyp during colonoscopy. RESULTS: A total of 533 colonoscopies were included. ADR was 25 % in the cohort. Mean age was 59 (SD 14.1). Two hundred and seventy (50.6 %) were done in the AM and 263 (49.4 %) were done in the PM. ADR was 29 % in the AM group compared to 21 % in the PM group (p = 0.03). Excluding time needed for polypectomy, the mean time taken for scope withdrawal was significantly longer in the morning group (12 min) compared with the afternoon group (10 min) (p = 0.002). The longer withdrawal time in the morning was significantly associated with increased ADRs (OR 1.104, 95 % CI 1.063-1.147) (p < 0.0001). CONCLUSION: Timing of colonoscopy is an independent predictor for ADR. Colonoscopies performed in the morning have a longer mean withdrawal time, thus leading to a significantly higher ADR. As endoscopists concentration decreases as the day progresses, this may account for the shorter time spent on colonoscopies on the afternoon.


Asunto(s)
Adenoma/diagnóstico por imagen , Competencia Clínica/estadística & datos numéricos , Colonoscopía/normas , Neoplasias Colorrectales/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Colonoscopía/estadística & datos numéricos , Bases de Datos Factuales , Fatiga , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Tiempo
4.
Ann Surg ; 261(3): 487-96, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24950263

RESUMEN

OBJECTIVE: Assess the impact of preoperative serum antitumor necrosis factor-α (anti-TNFα) drug levels on 30-day postoperative morbidity in inflammatory bowel disease (IBD) patients. BACKGROUND: Studies on the association of anti-TNFα drugs and postoperative outcomes in IBD are conflicting due to variable pharmacokinetics of anti-TNFα drugs. It remains to be seen whether preoperative serum anti-TNFα drug levels correlate with postoperative morbidity. METHODS: Thirty-day postoperative outcomes of consecutive IBD surgical patients with serum drawn within 7 days preoperatively were studied. The total serum level of 3 anti-TNFα drugs (infliximab, adalimumab, and certolizumab) was measured, with ≥ 0.98 µg/mL considered as detected. Data were also reviewed according to a clinical cutoff value of 3 µg/mL. RESULTS: A total of 217 patients [123 with Crohn disease (CD) and 94 with ulcerative colitis (UC)] were analyzed; 75 of 150 (50%) treated with anti-TNFα therapy did not have detected levels at the time of surgery. In the UC cohort, adverse postoperative outcome rates between the undetectable and detectable groups were similar when stratified according to type of UC surgery. In the CD cohort, there was a higher but statistically insignificant rate of adverse outcomes in the detectable versus undetectable groups. Using a cut off level of 3 µg/mL, postoperative morbidity (odds ratio [OR] = 2.5, P = 0.03) and infectious complications (OR = 3.0, P = 0.03) were significantly higher in the ≥ 3 µg/mL group. There were higher rates of postoperative morbidity (P = 0.047) and hospital readmissions (P = 0.04) in the ≥ 8 µg/mL compared with <3 µg/mL group. CONCLUSIONS: Increasing preoperative serum anti-TNFα drug levels are associated with adverse postoperative outcomes in CD but not UC patients.


Asunto(s)
Anticuerpos Monoclonales Humanizados/sangre , Anticuerpos Monoclonales/sangre , Fármacos Gastrointestinales/sangre , Fragmentos Fab de Inmunoglobulinas/sangre , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/cirugía , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab , Adulto , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Certolizumab Pegol , Terapia Combinada , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Femenino , Fármacos Gastrointestinales/uso terapéutico , Humanos , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Infliximab , Masculino , Polietilenglicoles/uso terapéutico , Sistema de Registros , Resultado del Tratamiento
5.
Biochim Biophys Acta ; 1828(8): 1802-13, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23562406

RESUMEN

A tryptophan (Trp)-rich region in the wheat endosperm protein, puroindoline A, was previously shown to possess potent antimicrobial activity against Gram-positive and Gram-negative bacteria and this was attributed to the peptide inducing membrane instability. In the present work, the antimicrobial activity of the corresponding Trp-rich region in the puroindoline B isoform was examined and its antimicrobial activity was characterized. Unexpectedly, the puroindoline B Trp-rich peptide (PuroB) was relatively inactive compared to the related puroindoline A peptide (PuroA), despite strong sequence similarity. Using the sequence of PuroA as a template, a series of PuroB variants were synthesized and the antimicrobial activity was restored. Interestingly, all of these PuroB peptides preferentially interacted with negatively charged phospholipids, but unlike PuroA, they did not disrupt the integrity of lipid bilayers. This suggests that the primary mode of action of the PuroB peptides involves an antimicrobial target other than the bacterial membrane. Further tests revealed that all of the puroindoline derived peptides bind deoxyribonucleic acid (DNA) and block macromolecular synthesis in vivo. Based on these results, it appears that the interaction between puroindoline derived peptides and membranes is only an initial step in the mode of action and that binding to intracellular targets, such as DNA and ribonucleic acid (RNA), contributes significantly to their antimicrobial mode of action.


Asunto(s)
Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Escherichia coli/efectos de los fármacos , Proteínas de Plantas/química , Staphylococcus aureus/efectos de los fármacos , Triptófano/metabolismo , Péptidos Catiónicos Antimicrobianos/síntesis química , Rastreo Diferencial de Calorimetría , Membrana Celular/metabolismo , Dicroismo Circular , ADN/metabolismo , Membrana Dobles de Lípidos/metabolismo , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Fosfolípidos/metabolismo , ARN/metabolismo , Espectrometría de Fluorescencia
6.
Ann Surg ; 260(4): 641-7; discussion 647-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25203881

RESUMEN

OBJECTIVE: Compare the feasibility and patient tolerance to either a clear fluid (CF) or low residue diet (LRD) started on postoperative day (POD) 1 after elective colorectal surgery. BACKGROUND: Diet advancement after surgery traditionally starts gradually with liquids, on the basis of fears that early solid intake may increase nausea, vomiting, and overall complications. A randomized controlled trial comparing LRD and CF on POD 1 was performed. METHODS: 111 elective colorectal surgery patients were randomized to CF (n = 57) or LRD (n = 54). The primary end point was vomiting on POD 2. Secondary endpoints included nausea score, days to flatus, length of hospital stay (LOS), and postoperative morbidity. RESULTS: Patient characteristics, surgical technique, intraoperative characteristics, and postoperative opioid use were similar between study arms. CF versus LRD results were as follows: POD2 vomiting (28% vs 14%; P = 0.09), and significant increase in mean nausea score (4.7 vs 3.5; P = 0.01), days to flatus (4.8 vs 3.7 days; P = 0.04), and LOS (7.0 vs 5.0 days; P = 0.01). LOS remained significantly shorter even after adjusting for significant covariates (laparoscopic technique, surgical site, postoperative comorbidity, stoma, and nasogastric tube) with LRD patients having an adjusted 1.4-day decrease in LOS (P < 0.01). There was no significant difference in postoperative morbidity between study arms. Multivariate analysis of all secondary endpoints confirmed an overall significant improvement in outcomes for LRD vs CF (P < 0.01). CONCLUSIONS: LRD, rather than CF, on POD1 after colorectal surgery is associated with less nausea, faster return of bowel function, and a shorter hospital stay without increasing postoperative morbidity.


Asunto(s)
Colon/cirugía , Dieta , Procedimientos Quirúrgicos Electivos/efectos adversos , Cuidados Posoperatorios/métodos , Náusea y Vómito Posoperatorios/etiología , Recto/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Defecación , Femenino , Flatulencia , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
7.
J Bacteriol ; 195(1): 46-55, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23104801

RESUMEN

Iron is an indispensable nutrient for most organisms. Ferric iron (Fe(3+)) predominates under aerobic conditions, while during oxygen limitation ferrous (Fe(2+)) iron is usually present. The Feo system is a bacterial ferrous iron transport system first discovered in Escherichia coli K-12. It consists of three genes, feoA, feoB, and feoC (yhgG). FeoB is thought to be the main transmembrane transporter while FeoC is considered to be a transcriptional regulator. Using multidimensional nuclear magnetic resonance (NMR) spectroscopy, we have determined the solution structure of E. coli FeoA. The structure of FeoA reveals a Src-homology 3 (SH3)-like fold. The structure is composed of a ß-barrel with two α-helices where one helix is positioned over the barrel. In comparison to the standard eukaryotic SH3 fold, FeoA has two additional α-helices. FeoA was further characterized by heteronuclear NMR dynamics measurements, which suggest that it is a monomeric, stable globular protein. Model-free analysis of the NMR relaxation results indicates that a slow conformational dynamic process is occurring in ß-strand 4 that may be important for function. (31)P NMR-based GTPase activity measurements with the N-terminal domain of FeoB (NFeoB) indicate a higher GTP hydrolysis rate in the presence of potassium than with sodium. Further enzymatic assays with NFeoB suggest that FeoA may not act as a GTPase-activating protein as previously proposed. These findings, together with bioinformatics and structural analyses, suggest that FeoA may have a different role, possibly interacting with the cytoplasmic domain of the highly conserved core portion of the FeoB transmembrane region.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Oxidorreductasas/metabolismo , Transporte Biológico Activo/fisiología , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Clonación Molecular , Escherichia/genética , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/fisiología , Proteínas de Transporte de Membrana/genética , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Mutación , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica
8.
Mol Pharm ; 10(3): 975-87, 2013 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-23331322

RESUMEN

Macrophages represent an important therapeutic target, because their activity has been implicated in the progression of debilitating diseases such as cancer and atherosclerosis. In this work, we designed and characterized pH-responsive polymeric micelles that were mannosylated using "click" chemistry to achieve CD206 (mannose receptor)-targeted siRNA delivery. CD206 is primarily expressed on macrophages and dendritic cells and upregulated in tumor-associated macrophages, a potentially useful target for cancer therapy. The mannosylated nanoparticles improved the delivery of siRNA into primary macrophages by 4-fold relative to the delivery of a nontargeted version of the same carrier (p < 0.01). Further, treatment for 24 h with the mannose-targeted siRNA carriers achieved 87 ± 10% knockdown of a model gene in primary macrophages, a cell type that is typically difficult to transfect. Finally, these nanoparticles were also avidly recognized and internalized by human macrophages and facilitated the delivery of 13-fold more siRNA into these cells than into model breast cancer cell lines. We anticipate that these mannose receptor-targeted, endosomolytic siRNA delivery nanoparticles will become an enabling technology for targeting macrophage activity in various diseases, especially those in which CD206 is upregulated in macrophages present within the pathologic site. This work also establishes a generalizable platform that could be applied for "click" functionalization with other targeting ligands to direct siRNA delivery.


Asunto(s)
Micelas , Polímeros/administración & dosificación , Polímeros/química , Animales , Células Cultivadas , Química Clic , Células Dendríticas/metabolismo , Citometría de Flujo , Humanos , Lectinas Tipo C/genética , Macrófagos/metabolismo , Receptor de Manosa , Lectinas de Unión a Manosa/genética , Microscopía Confocal , Nanopartículas/administración & dosificación , Nanopartículas/química , Interferencia de ARN , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Superficie Celular/genética
9.
Infect Dis (Lond) ; 54(9): 666-676, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35642330

RESUMEN

BACKGROUND: The COVID-19 pandemic has necessitated the need to rapidly make public health decisions. We systematically evaluated SARS-CoV-2 seropositivity to understand local COVID-19 epidemiology and support evidence-based public health decision making. METHODS: Residual blood samples were collected for SARS-CoV-2 receptor binding domain (RBD) IgG testing over a 1-5 day period monthly from 26 February 2021-9 July 2021 from six clinical laboratories across the province of Alberta, Canada. Monthly crude and adjusted (for age and gender) seropositivity were calculated. Results were linked to provincial administrative, laboratory, and vaccine databases. RESULTS: 60,632 individual blood samples were tested. Vaccination data were available for 98.8% of samples. Adjusted RBD IgG positivity rose from 11.9% (95% confidence interval [CI] 11.9-12.0%) in March 2021 to 70.2% (95% CI 70.2-70.3%) in July 2021 (p < .0001). Seropositivity rose from 9.4% (95% CI 9.3-9.4%) in March 2021 to 20.2% (95% CI 20.1-20.2%) in July 2021 in unvaccinated Albertans. Unvaccinated seropositive individuals were from geographic areas with significantly (p < .001) lower median household income, lower proportion of married/common-law relationships, larger average household size and higher proportions of visible minorities compared to seronegative unvaccinated individuals. In July 2021, the age groups with the lowest and highest seropositivity in unvaccinated Albertans were those ≥80 years (12.0%, 95% CI 5.3-18.6%) and 20-29 years (24.2%, 95% CI 19.6-28.8%), respectively. Of seropositive unvaccinated individuals, 50.2% (95% CI 45.9-54.5%) had no record of prior SARS-CoV-2 molecular testing. CONCLUSIONS: Longitudinal surveillance of SARS-CoV-2 seropositivity with data linkage is valuable for decision-making during the pandemic.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anciano de 80 o más Años , Alberta/epidemiología , Anticuerpos Antivirales , COVID-19/epidemiología , COVID-19/prevención & control , Humanos , Inmunoglobulina G , Pandemias , Vacunación
10.
J Biol Chem ; 285(40): 30558-66, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20659901

RESUMEN

Bacterial acyl carrier protein (ACP) is a highly anionic, 9 kDa protein that functions as a cofactor protein in fatty acid biosynthesis. Escherichia coli ACP is folded at neutral pH and in the absence of divalent cations, while Vibrio harveyi ACP, which is very similar at 86% sequence identity, is unfolded under the same conditions. V. harveyi ACP adopts a folded conformation upon the addition of divalent cations such as Ca(2+) and Mg(2+) and a mutant, A75H, was previously identified that restores the folded conformation at pH 7 in the absence of divalent cations. In this study we sought to understand the unique folding behavior of V. harveyi ACP using NMR spectroscopy and biophysical methods. The NMR solution structure of V. harveyi ACP A75H displays the canonical ACP structure with four helices surrounding a hydrophobic core, with a narrow pocket closed off from the solvent to house the acyl chain. His-75, which is charged at neutral pH, participates in a stacking interaction with Tyr-71 in the far C-terminal end of helix IV. pH titrations and the electrostatic profile of ACP suggest that V. harveyi ACP is destabilized by anionic charge repulsion around helix II that can be partially neutralized by His-75 and is further reduced by divalent cation binding. This is supported by differential scanning calorimetry data which indicate that calcium binding further increases the melting temperature of V. harveyi ACP A75H by ∼20 °C. Divalent cation binding does not alter ACP dynamics on the ps-ns timescale as determined by (15)N NMR relaxation experiments, however, it clearly stabilizes the protein fold as observed by hydrogen-deuterium exchange studies. Finally, we demonstrate that the E. coli ACP H75A mutant is similarly unfolded as wild-type V. harveyi ACP, further stressing the importance of this particular residue for proper protein folding.


Asunto(s)
Proteína Transportadora de Acilo/química , Proteínas Bacterianas/química , Calcio/química , Magnesio/química , Mutación Missense , Pliegue de Proteína , Vibrio/química , Proteína Transportadora de Acilo/genética , Proteína Transportadora de Acilo/metabolismo , Sustitución de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Calcio/metabolismo , Cationes Bivalentes/química , Medición de Intercambio de Deuterio , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Magnesio/metabolismo , Resonancia Magnética Nuclear Biomolecular , Unión Proteica , Estabilidad Proteica , Estructura Secundaria de Proteína , Vibrio/genética , Vibrio/metabolismo
11.
Front Psychol ; 12: 679586, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34566761

RESUMEN

Previous literature has documented the unique challenges encountered by mothers with substance abuse problems, which may hinder the ability to fulfill parenting responsibilities. Since there is evidence suggesting the engagement in meaning-making processes can help individuals reinterpret their transitions into parenthood and cope with parental stress, this study examined the meaning-making processes of motherhood among mothers with substance abuse problems. Sixteen Hong Kong Chinese mothers with a history of substance abuse were purposively selected and invited to narrate their life and maternal experiences in individual interviews. Based on the meaning-making model in the context of stress and coping, whereby global meaning refers to orienting system of an individual and situational meaning refers to the meaning one attributes to a particular situation, the global and situational meanings of participants related to motherhood and substance use, and their reappraised meanings in response to the discrepancies between global and situational meanings were analyzed. Using thematic analysis, the results showed that when faced with an internal conflict between global and situational meanings induced by substance abuse, most participants engaged in the meaning-making process of assimilation. Rather than changing their inherent parental beliefs and values, most participants adjusted their appraisals toward the situation, and hence made changes in their cognitions or behaviors such as making efforts to quit substance use or reprioritizing their parenting responsibilities. The analysis further revealed that being a mother provided a significant source of meaning to the participants in confronting highly stressful mothering experiences induced by substance abuse. Altogether, the findings suggest that a meaning-making approach may have benefits and implications for helping this population reorganize their self-perceptions, gain a clearer sense of future direction in motherhood, and achieve more positive life and parenting outcomes.

12.
Microbiol Spectr ; 9(1): e0029121, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34406813

RESUMEN

We systematically evaluated SARS-CoV-2 IgG positivity in a provincial cohort to understand the local epidemiology of COVID-19 and support evidence-based public health decisions. Residual blood samples were collected for serology testing over 5-day periods monthly from June 2020 to January 2021 from six clinical laboratories across the province of Alberta, Canada. A total of 93,993 individual patient samples were tested with a SARS-CoV-2 nucleocapsid antibody assay with positives confirmed using a spike antibody assay. Population-adjusted SARS-CoV-2 IgG seropositivity was 0.92% (95% confidence interval [CI]: 0.91 to 0.93%) shortly after the first COVID-19 wave in June 2020, increasing to 4.63% (95% CI: 4.61 to 4.65%) amid the second wave in January 2021. There was no significant difference in seropositivity between males and females (1.39% versus 1.27%; P = 0.11). Ages with highest seropositivity were 0 to 9 years (2.71%, 95% CI: 1.64 to 3.78%) followed by 20 to 29 years (1.58%, 95% CI: 1.12 to 2.04%), with the lowest rates seen in those aged 70 to 79 (0.79%, 95% CI: 0.65 to 0.93%) and >80 (0.78%, 95% CI: 0.60 to 0.97%). Compared to the seronegative group, seropositive patients inhabited geographic areas with lower household income ($87,500 versus $97,500; P < 0.001), larger household sizes, and higher proportions of people with education levels of secondary school or lower, as well as immigrants and visible minority groups (all P < 0.05). A total of 53.7% of seropositive individuals were potentially undetected cases with no prior positive COVID-19 nucleic acid test (NAAT). Antibodies were detectable in some patients up to 9 months post positive NAAT result. This seroprevalence study will continue to inform public health decisions by identifying at-risk demographics and geographical areas. IMPORTANCE Using SARS-CoV-2 serology testing, we assessed the proportion of people in Alberta, Canada (population 4.4 million) positive for COVID-19 antibodies, indicating previous infection, during the first two waves of the COVID-19 pandemic (prior to vaccination programs). Linking these results with sociodemographic population data provides valuable information as to which groups of the population are more likely to have been infected with the SARS-CoV-2 virus to help facilitate public health decision-making and interventions. We also compared seropositivity data with previous COVID-19 molecular testing results. Absence of antibody and molecular testing were highly correlated (95% negative concordance). Positive antibody correlation with a previous positive molecular test was low, suggesting the possibility of mild/asymptomatic infection or other reasons leading individuals from seeking medical attention. Our data highlight that the true estimate of population prevalence of COVID-19 is likely best informed by combining data from both serology and molecular testing.


Asunto(s)
Anticuerpos Antivirales/sangre , Vacunas contra la COVID-19/inmunología , COVID-19/epidemiología , COVID-19/inmunología , Pandemias , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alberta , Infecciones Asintomáticas/epidemiología , COVID-19/prevención & control , Niño , Preescolar , Femenino , Humanos , Inmunoglobulina G/sangre , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular , Prevalencia , Estudios Seroepidemiológicos , Clase Social , Adulto Joven
13.
Biometals ; 23(4): 601-11, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20596754

RESUMEN

Siderophores are biosynthetically produced and secreted by many bacteria, yeasts, fungi and plants, to scavenge for ferric iron (Fe(3+)). They are selective iron-chelators that have an extremely high affinity for binding this trivalent metal ion. The ferric ion is poorly soluble but it is the form of iron that is predominantly found in oxygenated environments. Siderophore uptake in bacteria has been extensively studied and over the last decade, detailed structural information for many of the proteins that are involved in their transport has become available. Specifically, numerous crystal structures for outer membrane siderophore transporters, as well as for soluble periplasmic siderophore-binding proteins, have been reported. Moreover, unique siderophore-binding proteins have recently been serendipitously discovered in humans, and the structures of some of their siderophore-complexes have been characterized. The binding pockets for different ferric-siderophores in these proteins have been described in great molecular detail. In addition to highlighting this structural information, in this review paper we will also briefly discuss the relevant chemical properties of iron, and provide a perspective on our current understanding of the human and bacterial iron uptake pathways. Potential clinical uses of siderophores will also be discussed. The emerging overall picture is that iron metabolism plays an extremely important role during bacterial infections. Because levels of free ferric iron in biological systems are always extremely low, there is serious competition for iron and for ferric-siderophores between pathogenic bacteria and the human or animal host.


Asunto(s)
Bacterias/metabolismo , Hierro/metabolismo , Sideróforos/metabolismo , Animales , Humanos , Inmunidad Innata , Hierro/química , Quelantes del Hierro/metabolismo , Quelantes del Hierro/uso terapéutico , Lipocalinas/química , Modelos Moleculares , Conformación Proteica , Sideróforos/química , Sideróforos/uso terapéutico
14.
Clin Biochem ; 76: 1-4, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31672645

RESUMEN

INTRODUCTION: We describe the implementation of an Alberta-wide intervention aimed at educating clinicians about redundant vitamin B12 testing. We hypothesized that the introduction of an educational comment outlining recommended vitamin B12 test intervals would reduce the annual number of vitamin B12 tests performed. MATERIALS AND METHODS: We performed a cross-sectional observational study that included all vitamin B12 tests ordered in Alberta between May 1, 2017 and April 30, 2018. An educational comment was appended to all vitamin B12 test results in Alberta beginning May 2, 2017. Using a simple seasonal model, we compared predicted versus observed vitamin B12 test volumes for the 12-month period following the introduction of the educational comment. The sole outcome measured was the monthly change in volume of vitamin B12 testing. A cost-analysis of the effects of the intervention on test volumes was also performed. RESULTS: Over the sum of the first 12 months of the intervention, 18,000 more vitamin B12 tests were ordered compared to the predicted value in Alberta. With an estimated cost of $7 per test, this resulted in a $126,000 increase in costs for vitamin B12 testing provincially. CONCLUSIONS: An educational intervention aimed at limiting inappropriate vitamin B12 testing in Alberta did not alter testing as desired. Multiple utilization management strategies and a longer observation period may be needed to reduce redundant vitamin B12 testing.


Asunto(s)
Educación Médica Continua/organización & administración , Vitamina B 12/sangre , Alberta , Estudios Transversales , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Masculino
15.
Clin Biochem ; 77: 32-35, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31891680

RESUMEN

INTRODUCTION: The avoidance of repeat chemistry testing such as Complete Blood Count (CBC) and Electrolyte Panel (EP) on clinically stable patients was identified as important utilization goals by Choosing Wisely Canada. The purpose of this study was to assess the volume of overutilization of CBC and EP in an inpatient setting in Alberta, Canada, and provide an estimated cost assessment of unnecessary testing. METHODS: The total laboratory testing volumes of two common test panels were collected retrospectively for one-year from January to December 2018. Data was collected on test panels performed in an emergency room (ER) and inpatient setting from three separate Laboratory Information Systems covering the provincial population in Alberta, Canada. Total initial test panel instances, total repeated panels, repeated panels that were previously normal or abnormal, and estimated costs were examined. Cost assessment was completed based on Reference Median Cost (RMC) analysis for each of these two common test panels. RESULTS: During the study period, 2,020,467 (CBC) and 1,455,983 (EP) initial test panel instances were recorded, of which 67.7% and 73.5% were repeated for the CBC and EP, respectively. There was a higher proportion of EP repeated inappropriately (previously normal; 35.6%) compared to CBCs (5.4%). The cost to the province for inappropriately repeating CBC and EP were estimated to be RMC $0.52 million and RMC $1.90 million CAD, respectively. CONCLUSION: Results from this study can assist policy makers in implementing utilization management initiatives and update clinical practice guidelines to reduce costs to healthcare without compromising patient care.


Asunto(s)
Recuento de Células Sanguíneas/normas , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Electrólitos/normas , Alberta , Humanos
16.
Data Brief ; 29: 105144, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32021889

RESUMEN

All laboratory tests performed within the province of Alberta in Canada are captured by three Laboratory Information Systems (LIS; Millennium, Sunquest and Meditech), which comprise the provincial Consolidated Laboratory Data Repository (CLDR). The following secondary laboratory data for electrolyte panel (EP) and complete blood count (CBC) test panels performed in emergency room (ER) and inpatient settings were collected from January 1 - December 31, 2018: total test panel volume, total number of test panels repeated, number of test panels repeated within the 24 hour period, test result, date of testing, time of test, and patient Provincial Health Number (PHN). Patient PHN were used as a linking variable to match subsequent tests performed on the same patient. The first time a test was recorded per patient was defined as the "index test". If the same test panel was performed within a 24-h period following the index test for the patient, data for the repeated test panel was also collected. The index test was defined as "normal" or "abnormal" according to established laboratory normal values and laboratory test reference ranges. For CBCs, we considered the panel to be abnormal if any of the hematocrit (Hct), hemoglobin (Hgb), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), platelet (PLT), red blood cell (RBC), red cell distribution width (RDW) or white blood cell (WBC) values were outside the normal laboratory reference range. For electrolyte panels, we considered the panel to be abnormal if any of the chloride (Cl), potassium (K), and sodium (Na) were outside of the normal laboratory reference range. All EP results were from clinical chemistry analyzers only. The reuse potential of this dataset can allow other jurisdictions in Canada to compare their redundant repeat testing in their hospital settings with this dataset as a benchmark. This article was submitted via another Elsevier journal as a co-submission ("Inappropriate repeat testing of complete blood count (CBC) and electrolytes in inpatients from Alberta, Canada" [1]), and readers should refer to the co-submission article for interpretation of the results.

17.
Data Brief ; 27: 104785, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31788514

RESUMEN

The data presented in this article is the provincial vitamin B12 test volume data for Alberta, Canada per month between April 1, 2015 and April 30, 2018. This data set was collected from the three different Alberta Public Laboratories Laboratory Information Systems: Cerner Millennium for Calgary, Sunquest for Edmonton, and MediTech for the remaining rural zones of Alberta (Bonnyville, Grand Prairie, Camrose, Red Deer, and Medicine Hat). An educational province-wide intervention aimed at reducing redundant testing was implemented on April 11, 2017 in Calgary, Alberta and Edmonton, Alberta and on May 2, 2017 in rural Alberta sites. All vitamin B12 test results in Alberta were appended with the educational comment "A normal test result indicates adequate stores and should not be repeated. However, if specific clinical situations require re-testing, the interval should not be sooner than 1 year." Provincial monthly test volumes prior to this intervention ranged from 54,182 to 73,522 tests per month and after this intervention ranged from 59,116 to 74,006 tests per month. The total number of vitamin B12 tests ordered over the 37 months in Alberta was 2,444,724; 690,448 tests were ordered in Calgary, 1,029,315 tests were ordered in Edmonton, and 724,961 tests were ordered in rural sites. This data article was submitted as a companion paper to the related research article, "Implementation of an educational province-wide intervention to reduce redundant vitamin B12 testing: a cross-sectional study"[1].

18.
Data Brief ; 23: 103748, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31372413

RESUMEN

Data presented in this article include the top 51 ordered laboratory tests in Calgary and surrounding area, Alberta, from January to December 2017. This data set was collected from Calgary Laboratory Service's Laboratory Information System, and included top 51 tests ordered from community (n = 11, 224, 330), inpatient (n = 2,340,594) and emergency (n = 1,670,062) settings. Test order mnemonic that were not true laboratory tests (eg: "extra PST tube", "extra tube", etc.) were excluded in the analysis. The top test ordered in all 3 test encounters was the complete blood count test (community encounter, n = 921, 873; inpatient setting, n = 357, 375; and emergency setting, n = 276, 954). This data article was submitted as a companion paper to the related research article, "Estimated costs of 51 commonly ordered laboratory tests in Canada" [1].

19.
Clin Biochem ; 65: 58-60, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30615855

RESUMEN

INTRODUCTION: Test cost display has been shown to reduce inappropriate laboratory test ordering practices in the United States. Unfortunately, such a system is limited in the Canadian publically funded healthcare environment. Many Canadian physicians inaccurately estimate the cost of laboratory tests, which may contribute to mis-utilization. Here, we provide an estimated cost of over 50 commonly ordered laboratory tests in Canada as an educational tool for physicians. METHODS: Test volume data was collected from Calgary Laboratory Services' Laboratory Information System in order to determine which laboratory and diagnostic tests are most commonly ordered in Calgary and its surrounding area. Reference median cost (RMC) of fifty one commonly ordered test was calculated by determining the price list of all-inclusive indirect costs from six different clinical laboratories across Canada. RESULTS: Of the 51 laboratory tests included, the minimum RMC was $5 CAD (eg: albumin, calcium, urea), and the maximum RMC was $300 (surgical pathology report). CONCLUSIONS: A caveat to the provided list of test costs is that it is only an estimate and may differ from what each individual clinical laboratories charges to third parties or for research purposes. However, this list can serve as an educational tool and raise awareness for Canadian physicians on the relative costs of laboratory tests.


Asunto(s)
Técnicas de Laboratorio Clínico/economía , Pruebas Diagnósticas de Rutina/economía , Canadá , Costos y Análisis de Costo , Humanos
20.
J Phys Chem B ; 110(18): 9027-33, 2006 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-16671711

RESUMEN

Peptide nucleic acid amphiphiles (PNAA) are a promising set of materials for sequence-specific separation of nucleic acids from complex mixtures. To implement PNAA in micellar separations, the morphology and size of PNAA micelles in the presence and absence of a sodium dodecyl sulfate (SDS) cosurfactant have been studied by small-angle X-ray scattering and dynamic light scattering. We find that a 6-mer PNAA with a 12-carbon n-alkane tail forms ellipsoidal micelles (a = 5.15 nm; b = 3.20 nm) above its critical micelle concentration (CMC) of 110.9 microM. On addition of a stoichiometric amount of complementary DNA, PNAA hybridizes to DNA, suppressing the formation of PNAA micelles. At a ratio of 19:1 SDS/PNAA (total concentration = 20 mM), spherical micelles are formed with outer radius Rs = 2.67 nm, slightly larger than spherical micelles of pure SDS. Capillary electrophoresis studies show that PNAA/DNA duplexes do not comicellize with SDS micelles. No such effects are observed using noncomplementary DNA. The shape and size of the PNAA micelles is also verified by dynamic light scattering (DLS) studies. These results provide an interesting case study with competing electrostatic, hydrophobic, and hydrogen-bonding interactions in micellar systems and make possible the use of PNAA in micellar separations of DNA oligomers.


Asunto(s)
ADN/química , Micelas , Modelos Químicos , Ácidos Nucleicos de Péptidos/síntesis química , Tensoactivos/síntesis química , Técnicas Biosensibles , Electroforesis Capilar , Hibridación de Ácido Nucleico , Tamaño de la Partícula , Ácidos Nucleicos de Péptidos/química , Dispersión del Ángulo Pequeño , Dodecil Sulfato de Sodio/química , Tensoactivos/química , Difracción de Rayos X
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