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1.
Nat Commun ; 15(1): 7187, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39168966

RESUMEN

Malignant mesothelioma is a rare tumour caused by asbestos exposure that originates mainly from the pleural lining or the peritoneum. Treatment options are limited, and the prognosis is dismal. Although immune checkpoint blockade (ICB) can improve survival outcomes, the determinants of responsiveness remain elusive. Here, we report the outcomes of a multi-centre phase II clinical trial (MiST4, NCT03654833) evaluating atezolizumab and bevacizumab (AtzBev) in patients with relapsed mesothelioma. We also use tumour tissue and gut microbiome sequencing, as well as tumour spatial immunophenotyping to identify factors associated with treatment response. MIST4 met its primary endpoint with 50% 12-week disease control, and the treatment was tolerable. Aneuploidy, notably uniparental disomy (UPD), homologous recombination deficiency (HRD), epithelial-mesenchymal transition and inflammation with CD68+ monocytes were identified as tumour-intrinsic resistance factors. The log-ratio of gut-resident microbial genera positively correlated with radiological response to AtzBev and CD8+ T cell infiltration, but was inversely correlated with UPD, HRD and tumour infiltration by CD68+ monocytes. In summary, a model is proposed in which both intrinsic and extrinsic determinants in mesothelioma cooperate to modify the tumour microenvironment and confer clinical sensitivity to AtzBev. Gut microbiota represent a potentially modifiable factor with potential to improve immunotherapy outcomes for individuals with this cancer of unmet need.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antígeno B7-H1 , Bevacizumab , Microbioma Gastrointestinal , Inhibidores de Puntos de Control Inmunológico , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Bevacizumab/uso terapéutico , Bevacizumab/farmacología , Masculino , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Anticuerpos Monoclonales Humanizados/uso terapéutico , Femenino , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Persona de Mediana Edad , Anciano , Mesotelioma Maligno/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/metabolismo , Mesotelioma/inmunología , Mesotelioma/tratamiento farmacológico , Mesotelioma/microbiología , Mesotelioma/patología , Microambiente Tumoral/inmunología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/microbiología , Resultado del Tratamiento
2.
Rev Med Virol ; 34(3): e2542, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747622

RESUMEN

Influenza in dogs holds considerable public health significance due to their close companionship with humans, yet several facets of this phenomenon remain largely unexplored. This study undertook a systematic review and meta-analysis of observational studies to gauge the global seroprevalence of influenza in dogs. We also assessed whether pet dogs exhibited a higher seroprevalence of influenza compared to non-pet dogs, explored seasonal variations in seroprevalence, scrutinised the design and reporting standards of existing studies, and elucidated the geographical distribution of canine influenza virus (cIV). A comprehensive analysis of 97 studies spanning 27 countries revealed that seroprevalence of various influenza strains in dogs consistently registered below 10% and exhibited relative stability over the past decade. Significantly, we noted that seroprevalence of human influenza virus was notably higher in pet dogs compared to their non-pet counterparts, whereas seroprevalence of other influenza strains remained relatively uniform among both categories of dogs. Seasonal variations in seroprevalence of cIV were not observed. In summary, our findings indicated the global circulation of cIV strains H3N2 and H3N8, with other strains primarily confined to China. Given the lack of reported cases of the transmission of cIV from dogs to humans, our findings suggest a higher risk of reverse zoonosis than zoonosis. Finally, we strongly advocate for standardised reporting guidelines to underpin future canine influenza research endeavours.


Asunto(s)
Enfermedades de los Perros , Infecciones por Orthomyxoviridae , Animales , Perros , Humanos , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/virología , Salud Global , Virus de la Influenza A/inmunología , Virus de la Influenza A/aislamiento & purificación , Subtipo H3N2 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/veterinaria , Infecciones por Orthomyxoviridae/virología , Infecciones por Orthomyxoviridae/inmunología , Prevalencia , Estaciones del Año , Estudios Seroepidemiológicos
3.
Nat Commun ; 15(1): 1735, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443398

RESUMEN

Ice core records of carbon dioxide (CO2) throughout the last 2000 years provide context for the unprecedented anthropogenic rise in atmospheric CO2 and insights into global carbon cycle dynamics. Yet the atmospheric history of CO2 remains uncertain in some time intervals. Here we present measurements of CO2 and methane (CH4) in the Skytrain ice core from 1450 to 1700 CE. Results suggest a sudden decrease in CO2 around 1610 CE in one widely used record may be an artefact of a small number of anomalously low values. Our analysis supports a more gradual decrease in CO2 of 0.5 ppm per decade from 1516 to 1670 CE, with an inferred land carbon sink of 2.6 PgC per decade. This corroborates modelled scenarios of large-scale reorganisation of land use in the Americas following New World-Old World contact, whereas a rapid decrease in CO2 at 1610 CE is incompatible with even the most extreme land-use change scenarios.

4.
Pediatr Qual Saf ; 8(4): e662, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37434595

RESUMEN

Enrollment in high-quality early childhood education (ECE) improves educational and health outcomes and can mitigate racial and economic disparities. Pediatricians are encouraged to promote ECE yet lack the time and knowledge to assist families effectively. In 2016, our academic primary care center hired an ECE Navigator to promote ECE and help families enroll. Our SMART aims were to increase the number of children with facilitated referrals to high-quality ECE programs from 0 to 15 per month and to confirm enrollment on a subset to achieve an enrollment rate of 50% by December 31, 2020. Methods: We used the Institute for Healthcare Improvement's Model for Improvement. Interventions included system changes in partnership with ECE agencies (eg, interactive map of subsidized preschool options, streamlined enrollment forms), case management with families, and population-based approaches to understand families' needs and the program's overall impact. We plotted the number of monthly facilitated referrals and the percentage of referrals enrolled on run and control charts. We used standard probability-based rules to identify special causes. Results: Facilitated referrals increased from 0 to 29 per month and remained above 15. The percentage of enrolled referrals increased from 30% to 74% in 2018, then decreased to 27% in 2020 when childcare availability declined during the pandemic. Conclusions: Our innovative ECE partnership improved access to high-quality ECE. Interventions could be adopted in part or whole by other clinical practices or WIC offices to equitably improve early childhood experiences for low-income families and racial minorities.

6.
J Assoc Med Microbiol Infect Dis Can ; 7(2): 135-139, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36337354

RESUMEN

BACKGROUND: Tularemia is a rare zoonosis caused by Francisella tularensis, a small gram-negative intracellular coccobacillus. Transmission occurs through direct contact with small mammals such as hares and rabbits, exposure to ticks, or ingestion or inhalation of aerosolized particles. It is a highly variable disease with six subtypes based on clinical features. Tularemia is a very rare disease in Canada, with only 0.01 cases per 100,000 people reported in 2017. METHODS: In this case report, we describe two cases of tularemia affecting hunters from rural Newfoundland and Labrador. RESULTS: The first case describes a patient with glandular tularemia diagnosed with serology; the second describes a patient with typhoidal tularemia diagnosed on blood culture. Both patients recovered after treatment with gentamicin. DISCUSSION: These cases highlight the importance of eliciting a careful social history from patients presenting with an unexplained febrile illness. Tularemia should be considered in the differential diagnosis of fever after hunting in rural areas.


HISTORIQUE: La tularémie est une zoonose rare causée par le Francisella tularensis, un petit coccobacille intracellulaire à Gram négatif. La transmission se produit par contact direct avec des petits mammifères comme des lièvres et des lapins, l'exposition aux tiques, l'ingestion ou l'inhalation de particules aérosolisées. C'est une maladie extrêmement variable possédant six sous-types en fonction des caractéristiques cliniques. La tularémie est une maladie très rare au Canada; seulement 0,01 cas sur 100 000 habitants a été signalé en 2017. MÉTHODOLOGIE: Dans le présent rapport de cas, les auteurs décrivent deux cas de tularémie chez des chasseurs de régions rurales de Terre-Neuve-et-Labrador. RÉSULTATS: Le premier cas décrit un patient atteint de tularémie glandulaire diagnostiquée par sérologie et le deuxième, un patient atteint d'une tularémie typhoïde diagnostiquée par culture sanguine. Les deux patients se sont rétablis après avoir été traités à la gentamicine. DISCUSSION: Ces cas font ressortir l'importance d'une histoire sociale attentive des patients qui ont consulté à cause d'une maladie fébrile inexpliquée. Il faut envisager une tularémie lors du diagnostic différentiel de fièvre chez des personnes qui ont chassé dans des régions rurales.

7.
Ann Plast Surg ; 88(2 Suppl 2): S138-S141, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35312641

RESUMEN

ABSTRACT: Initial hand dressings for burned hands should be compatible with preservation of skin substitutes and grafts, splinting, and active motion. We have developed a standardized glove dressing directed at these requirements. Early experience with this glove dressing has included feasible clinical application, 7- to 10-minute application time, and 90% preservation of total active range of motion in a normal hand placed in the dressing under test conditions.


Asunto(s)
Quemaduras , Traumatismos de la Mano , Traumatismos de la Muñeca , Vendajes , Quemaduras/terapia , Mano , Traumatismos de la Mano/cirugía , Humanos
8.
Lancet Oncol ; 23(3): 374-381, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35157829

RESUMEN

BACKGROUND: Genetically stratified therapy for malignant mesothelioma is unavailable. Mesotheliomas frequently harbour loss of the chromosome 9p21.3 locus (CDKN2A-MTAP), which is associated with shorter overall survival due to loss of the tumour suppressor p16ink4A, an endogenous suppressor of cyclin-dependent kinase (CDK)4 and CDK6. Genetic restoration of p16ink4A suppresses mesothelioma in preclinical models, underpinning the rationale for targeting CDK4 and CDK6 in p16ink4A-negative mesothelioma. We developed a multicentre, stratified, phase 2 trial to test this hypothesis. METHODS: The MiST2 study was a single-arm, open-label, phase 2 clinical trial done two UK centres. Patients older than 18 years with any histologically confirmed subtype of mesothelioma (pleural or peritoneal) with radiological progression after at least one course of platinum-based chemotherapy were molecularly screened by immunohistochemistry for p16ink4A. Patients with p16ink4A-negative mesothelioma were eligible for inclusion in the study. Patients were required to have measurable disease by modified Response Evaluation Criteria in Solid Tumours version 1.1 for malignant mesothelioma, a predicted life expectancy of at least 12 weeks, and an Eastern Cooperative Oncology Group performance status score of 0-1. Patients received oral abemaciclib 200 mg twice daily, administered in 28-day cycles for 24 weeks. The primary endpoint was the disease control rate (patients with complete responses, partial responses, or stable disease) at 12 weeks. The null hypothesis could be rejected if at least 11 patients had disease control. The efficacy and safety populations were defined as all patients who received at least one dose of the study drug. The study is registered with ClinicalTrials.gov, NCT03654833, and is ongoing (but MiST2 is now closed). FINDINGS: Between Sept 31, 2019, and March 2, 2020, 27 eligible patients consented to molecular screening. The median follow-up was 18·4 weeks (IQR 6·7-23·9). One patient was excluded before treatment because of a serious adverse event before study drug allocation. 26 (100%) of 26 treated patients were p16ink4A deficient and received at least one dose of abemaciclib. Disease control at 12 weeks was reported in 14 (54%) of 26 patients (95% CI 36-71). Grade 3 or worse treatment-related adverse events (of any cause) occurred in eight (27%) of 26 patients (diarrhoea, dyspnoea, thrombocytopenia, vomiting, urinary tract infection, increased alanine aminotransferase, ascites, chest infection or suspected chest infection, neutropenic sepsis, alopecia, blood clot left calf, fall [broken neck and collar bone], haemoptysis, lower respiratory tract infection, and pulmonary embolism). Grade 3 or worse treatment-related adverse events occurred in three (12%) of 26 patients (diarrhoea, thrombocytopenia, vomiting, increased alanine aminotransferase, and pulmonary embolism). Serious adverse events occurred in six (23%) of 26 patients, leading to treatment discontinuation in one (4%) patient (diarrhoea, urinary tract infection, chest infection, neutropenic sepsis, fall [broken neck and collar bone], haemoptysis, lower respiratory tract infection, and pulmonary embolism). One patient had a serious adverse event related to abemaciclib (diarrhoea). One (4%) of 26 patients died from an adverse event (neutropenic sepsis). INTERPRETATION: This study met its primary endpoint, showing promising clinical activity of abemaciclib in patients with p16ink4A-negative mesothelioma who were previously treated with chemotherapy, and warrants its further investigation in a randomised study as a targeted stratified therapy. FUNDING: University of Leicester, Asthma UK and British Lung Foundation Partnership, and the Victor Dahdaleh Foundation.


Asunto(s)
Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurales , Embolia Pulmonar , Infecciones del Sistema Respiratorio , Sepsis , Trombocitopenia , Alanina Transaminasa , Aminopiridinas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bencimidazoles , Diarrea/etiología , Hemoptisis/tratamiento farmacológico , Hemoptisis/etiología , Humanos , Mesotelioma/tratamiento farmacológico , Mesotelioma/genética , Neoplasias Pleurales/tratamiento farmacológico , Embolia Pulmonar/tratamiento farmacológico , Embolia Pulmonar/etiología , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/etiología , Vómitos/tratamiento farmacológico
9.
Oncotarget ; 12(8): 726-739, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33889297

RESUMEN

We developed and analytically validated a comprehensive genomic profiling (CGP) assay, GEM ExTra, for patients with advanced solid tumors that uses Next Generation Sequencing (NGS) to characterize whole exomes employing a paired tumor-normal subtraction methodology. The assay detects single nucleotide variants (SNV), indels, focal copy number alterations (CNA), TERT promoter region, as well as tumor mutation burden (TMB) and microsatellite instability (MSI) status. Additionally, the assay incorporates whole transcriptome sequencing of the tumor sample that allows for the detection of gene fusions and select special transcripts, including AR-V7, EGFR vIII, EGFRvIV, and MET exon 14 skipping events. The assay has a mean target coverage of 180X for the normal (germline) and 400X for tumor DNA including enhanced probe design to facilitate the sequencing of difficult regions. Proprietary bioinformatics, paired with comprehensive clinical curation results in reporting that defines clinically actionable, FDA-approved, and clinical trial drug options for the management of the patient's cancer. GEM ExTra demonstrated analytic specificity (PPV) of > 99.9% and analytic sensitivity of 98.8%. Application of GEM ExTra to 1,435 patient samples revealed clinically actionable alterations in 83.9% of reports, including 31 (2.5%) where therapeutic recommendations were based on RNA fusion findings only.

10.
Biotechnol Prog ; 37(4): e3158, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33891804

RESUMEN

Site specific integration (SSI) expression systems offer robust means of generating highly productive and stable cell lines for traditional monoclonal antibodies. As complex modalities such as antibody-like molecules comprised of greater than two peptides become more prevalent, greater emphasis needs to be placed on the ability to produce appreciable quantities of the correct product of interest (POI). The ability to screen several transcript stoichiometries could play a large role in ensuring high amounts of the correct POI. Here we illustrate implementation of an SSI expression system with a single site of integration for development and production of a multi-chain, bi-specific molecule. A SSI vector with a single copy of all of the genes of interest was initially selected for stable Chinese hamster ovary transfection. While the resulting transfection pools generated low levels of the desired heterodimer, utilizing an intensive clone screen strategy, we were able to identify clones having significantly higher levels of POI. In-depth genotypic characterization of clones having the desirable phenotype revealed that a duplication of the light chain within the landing pad was responsible for producing the intended molecule. Retrospective transfection pool analysis using a vector configuration mimicking the transgene configuration found in the clones, as well as other vector configurations, yielded more favorable results with respect to % POI. Overall, the study demonstrated that despite the theoretical static nature of the SSI expression system, enough heterogeneity existed to yield clones having significantly different transgene phenotypes/genotypes and support production of a complex multi-chain molecule.


Asunto(s)
Cricetulus , Animales , Células CHO , Cricetinae , Proteínas Recombinantes/genética , Estudios Retrospectivos , Transfección , Transgenes
11.
MAbs ; 13(1): 1850395, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33459147

RESUMEN

We report here the discovery and optimization of a novel T cell retargeting anti-GUCY2C x anti-CD3ε bispecific antibody for the treatment of solid tumors. Using a combination of hybridoma, phage display and rational design protein engineering, we have developed a fully humanized and manufacturable CD3 bispecific antibody that demonstrates favorable pharmacokinetic properties and potent in vivo efficacy. Anti-GUCY2C and anti-CD3ε antibodies derived from mouse hybridomas were first humanized into well-behaved human variable region frameworks with full retention of binding and T-cell mediated cytotoxic activity. To address potential manufacturability concerns, multiple approaches were taken in parallel to optimize and de-risk the two antibody variable regions. These approaches included structure-guided rational mutagenesis and phage display-based optimization, focusing on improving stability, reducing polyreactivity and self-association potential, removing chemical liabilities and proteolytic cleavage sites, and de-risking immunogenicity. Employing rapid library construction methods as well as automated phage display and high-throughput protein production workflows enabled efficient generation of an optimized bispecific antibody with desirable manufacturability properties, high stability, and low nonspecific binding. Proteolytic cleavage and deamidation in complementarity-determining regions were also successfully addressed. Collectively, these improvements translated to a molecule with potent single-agent in vivo efficacy in a tumor cell line adoptive transfer model and a cynomolgus monkey pharmacokinetic profile (half-life>4.5 days) suitable for clinical development. Clinical evaluation of PF-07062119 is ongoing.


Asunto(s)
Anticuerpos Biespecíficos/inmunología , Complejo CD3/inmunología , Inmunoterapia Adoptiva/métodos , Neoplasias/terapia , Receptores de Enterotoxina/inmunología , Animales , Anticuerpos Biespecíficos/farmacocinética , Anticuerpos Biespecíficos/uso terapéutico , Línea Celular Tumoral , Femenino , Humanos , Hibridomas , Macaca fascicularis/inmunología , Macaca fascicularis/metabolismo , Ratones Endogámicos BALB C , Neoplasias/inmunología , Neoplasias/metabolismo , Ingeniería de Proteínas/métodos , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/farmacocinética , Anticuerpos de Cadena Única/uso terapéutico , Linfocitos T/inmunología , Linfocitos T/metabolismo
12.
Lancet Respir Med ; 9(6): 593-600, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33515503

RESUMEN

BACKGROUND: Malignant mesothelioma remains an incurable cancer, with no effective treatments in the setting of relapsed disease. Homologous recombination deficiency predicts sensitivity to poly (ADP-ribose) polymerase (PARP) inhibitors. In mesothelioma, BRCA1-associated protein 1 carboxy-terminal hydrolase (BAP1), which regulates DNA repair, is frequently mutated. We aimed to test the hypothesis that BAP1-deficient or BRCA1-deficient mesotheliomas would be sensitive to PARP inhibition by rucaparib. METHODS: We did a single-centre, open-label, single-arm, phase 2a trial in Leicester, UK, with prospective molecular stratification (Mesothelioma-Stratified Therapy 1 [MiST1]). Patients aged 18 years or older who had radiologically progressing, histologically confirmed, malignant mesothelioma after at least one course of systemic treatment; with cytoplasmic-BAP1-deficient or BRCA1-deficient mesothelioma (pleural or peritoneal or other primary localisation), and who met the other inclusion criteria, were deemed eligible. All eligible patients who consented to take part were given rucaparib 600 mg twice a day orally, for six cycles of 28 days, or until disease progression, unacceptable toxicity, withdrawal of consent, or death. Response was measured by CT scan every 6 weeks. The primary outcome was disease control (complete response, partial response, or stable disease) at 12 weeks in all patients who received study drug; secondary outcomes were the safety and toxicity profile, objective response rate (proportion of complete or partial responses), and disease control rate at 24 weeks. Recruitment is now closed. This trial is registered with ClinicalTrials.gov, NCT03654833. FINDINGS: Between Feb 9 and June 10, 2019, we enrolled 26 molecularly and clinically eligible patients. Ten (38%) of 26 patients were BAP1 negative and BRCA1 negative, 23 patients (89%) were BAP1 negative, and 13 patients (50%) were BRCA1 negative. Disease control rate at 12 weeks was 58% (95% CI 37-77; 15 of 26 patients), and at 24 weeks was 23% (9-44; six of 26 patients). Rucaparib was well tolerated, with 15 (9%) of 166 adverse events being grade 3 or 4, which were seen in nine (35%) of 26 patients, and there were no deaths. The most common grade 1-2 adverse events were nausea (18 [69%] of 26 patients), fatigue (14 patients [54%]), and decreased appetite (ten patients [38%]). The most common grade 3-4 adverse events were upper respiratory tract infection (three patients [12%]) and anaemia (three patients [12%]). All six cycles of rucaparib were received by eight (31%) of 26 patients. One or more dose reductions occurred in nine patients (35%). INTERPRETATION: Rucaparib in patients with BAP1-negative or BRCA1-negative mesothelioma met the prespecified criteria for success, showing promising activity with manageable toxicity. Further investigation of homologous recombination deficiency mutations is planned to refine the identification of predictive biomarkers for PARP inhibition in mesothelioma. FUNDING: University of Leicester (Leicester, UK), Asthma UK and British Lung Foundation Partnership, and the Victor Dahdaleh Foundation (Toronto, ON, Canada).


Asunto(s)
Indoles/uso terapéutico , Mesotelioma/tratamiento farmacológico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Anciano , Proteína BRCA1 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Proteínas Supresoras de Tumor , Ubiquitina Tiolesterasa , Reino Unido
13.
Abdom Radiol (NY) ; 46(6): 2961-2967, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33386919

RESUMEN

PURPOSE: CT angiography (CTA) requires vascular access with flow rates of 5-7 mL/s. Hemodialysis (HD) is performed at 6-10 mL/s. The purpose of our study is to evaluate the structural integrity of HD catheters in the administration of contrast media via a mechanical power injector under varying conditions. METHODS: Four HD catheters were evaluated in an in vitro study. Tested were contrast media type (iopamidol 300 and 370 mgI/mL), temperature (25 and 37 °C), catheter diameter (14 Fr to 16 Fr all with double-lumen capacity), catheter length (19-32 cm), and simultaneous double-lumen or single-lumen injection within each of the catheters. Peak plateau pressures (psi) were recorded with flow rates from 5 to 20 mL/s in 5 mL/s increments. In total, 864 unique injections were performed. RESULTS: No catheter failure (bulging/rupture) was observed in 864 injections. Maximum pressure for single-lumen injection was 51.7 psi (double-lumen: 26.3 psi). Peak pressures were significantly lower in simultaneous double-lumen vs. single-lumen injections (p < 0.001) and low vs. high viscosity contrast media (p < 0.001). Neither larger vs. smaller diameter lumens (p = 0.221) nor single-lumen injection in arterial vs. venous (p = 0.834) were significantly different. CONCLUSION: HD catheters can be used to safely administer iodinated contrast media via mechanical power injection in in vitro operating conditions. Maximum peak pressure is below the manufacturer's 30 psi limit at flow rates up to 20 mL/s in double-lumen injections and up to 10 mL/s in single-lumen injections, which is higher than the usual maximum of 8 mL/s for CT angiography in clinical settings.


Asunto(s)
Cateterismo Venoso Central , Medios de Contraste , Catéteres , Angiografía por Tomografía Computarizada , Humanos , Inyecciones Intravenosas , Diálisis Renal
14.
PLoS One ; 15(5): e0232713, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32379792

RESUMEN

For an antibody to be a successful therapeutic many competing factors require optimization, including binding affinity, biophysical characteristics, and immunogenicity risk. Additional constraints may arise from the need to formulate antibodies at high concentrations (>150 mg/ml) to enable subcutaneous dosing with reasonable volume (ideally <1.0 mL). Unfortunately, antibodies at high concentrations may exhibit high viscosities that place impractical constraints (such as multiple injections or large needle diameters) on delivery and impede efficient manufacturing. Here we describe the optimization of an anti-PDGF-BB antibody to reduce viscosity, enabling an increase in the formulated concentration from 80 mg/ml to greater than 160 mg/ml, while maintaining the binding affinity. We performed two rounds of structure guided rational design to optimize the surface electrostatic properties. Analysis of this set demonstrated that a net-positive charge change, and disruption of negative charge patches were associated with decreased viscosity, but the effect was greatly dependent on the local surface environment. Our work here provides a comprehensive study exploring a wide sampling of charge-changes in the Fv and CDR regions along with targeting multiple negative charge patches. In total, we generated viscosity measurements for 40 unique antibody variants with full sequence information which provides a significantly larger and more complete dataset than has previously been reported.


Asunto(s)
Anticuerpos Monoclonales/química , Inmunoglobulina G/química , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Becaplermina/inmunología , Diseño Asistido por Computadora , Humanos , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Modelos Moleculares , Mutación , Conformación Proteica , Propiedades de Superficie , Viscosidad
15.
Comput Biol Med ; 118: 103640, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32174319

RESUMEN

Decompression sickness (DCS) is a condition associated with reductions in ambient pressure during underwater diving and altitude exposure. Determining the risk of DCS from a dive exposure remains an active area of research, with the goal of developing safe decompression schedules to mitigate the occurrence of DCS. This work develops a probabilistic model for the trinomial outcome of full, marginal, and no DCS. The model treats full DCS and marginal DCS as separate, fully weighted hierarchical events. Six variants of exponential-exponential (EE) and linear-exponential (LE) decompression models were optimized to fit dive outcomes from the BIG292 empirical human dive trial data of 3322 exposures. Using the log likelihood difference test, the LE1 trinomial marginal model was determined to provide the best fit for the data. The LE1 trinomial marginal model can be used to better understand decompression schedules, expanding upon binomial models which treat marginal DCS as either a fractionally weighted event or a non-event. Future work could investigate whether the use of marginal DCS cases improves multinomial probabilistic DCS model performance. Model improvement could include the addition of a fourth outcome, where full DCS is split and categorized as serious or mild DCS, creating a tetranomial model with serious, mild, marginal, and no DCS outcomes for comparison with the presently developed model.


Asunto(s)
Enfermedad de Descompresión , Buceo , Buceo/efectos adversos , Humanos , Modelos Estadísticos , Probabilidad
16.
Anal Chem ; 91(8): 5051-5057, 2019 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-30893554

RESUMEN

Many atmospheric organic compounds are long-lived enough to be transported from their sources to polar regions and high mountain environments where they can be trapped in ice archives. While inorganic components in ice archives have been studied extensively to identify past climate changes, organic compounds have rarely been used to assess paleo-environmental changes, mainly due to the lack of suitable analytical methods. This study presents a new method of direct injection high performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, without the need of preconcentrating the melted ice, for the determination of a series of novel biomarkers in ice core samples indicative of primary and secondary terrestrial and marine organic aerosol sources. Eliminating a preconcentration step reduces contamination potential and decreases the required sample volume thus allowing a higher time resolution in the archives. The method is characterized by limits of detection (LODs) in the range of 0.01-15 ppb, depending on the analyte, and accuracy evaluated through an interlaboratory comparison. We find that many components in secondary organic aerosols (SOAs) are clearly detectable at concentrations comparable to those previously observed in replicate preconcentrated ice samples from the Belukha glacier, Russian Altai Mountains. Some compounds with low recoveries in the preconcentration steps are now detectable in samples with this new direct injection method significantly increasing the range of environmental processes and sources that become accessible for paleo-climate studies.


Asunto(s)
Biomarcadores/análisis , Cromatografía Líquida de Alta Presión/métodos , Monitoreo del Ambiente/métodos , Hielo , Límite de Detección , Espectrometría de Masas/métodos , Océanos y Mares
17.
Talanta ; 194: 233-242, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30609525

RESUMEN

The majority of atmospheric compounds measured in ice cores are inorganic, while analysis of their organic counterparts is a less well developed field. In recent years, understanding of formation, transport pathways and preservation of these compounds in ice and snow has improved, showing great potential for their use as biomarkers in ice cores. This study presents an optimised analytical technique for quantification of terrestrial and marine biosphere emissions of secondary organic aerosol (SOA) components and fatty acids in ice using HPLC-MS analysis. Concentrations of organic compounds in snow and ice are extremely low (typically ppb or ppt levels) and thus pre-concentration is required prior to analysis. Stir bar sorptive extraction (SBSE) showed potential for fatty acid compounds, but failed to recover SOA compounds. Solid phase extraction (SPE) recovered compounds across both organic groups but methods improving some recoveries came at the expense of others, and background contamination of fatty acids was high. Rotary evaporation was by far the best performing method across both SOA and fatty acid compounds, with average recoveries of 80%. The optimised preconcentration - HPLC-MS method achieved repeatability of 9% averaged for all compounds. In environmental samples, both concentrations and seasonal trends were observed to be reproducible when analysed in two different laboratories using the same method.


Asunto(s)
Aerosoles/análisis , Organismos Acuáticos/química , Cromatografía Liquida/métodos , Ácidos Grasos/análisis , Hielo , Espectrometría de Masas en Tándem/métodos , Aerosoles/aislamiento & purificación , Biomarcadores/análisis , Calibración , Ácidos Grasos/aislamiento & purificación , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Volatilización
18.
J Health Psychol ; 24(13): 1897-1908, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-28810456

RESUMEN

Limited research has explored preoperative anxiety through qualitative methodologies. This study aimed to identify specific factors that contribute to preoperative anxiety. A total of 17 patients awaiting general, plastic reconstructive and hand, orthopaedic, or ear, nose, and throat/otorhinolaryngology surgery were interviewed about their concerns in a public hospital. Thematic analysis identified five main sources of anxiety: surgical procedures, surgical complications, symptoms, recovery process, and organisation and delivery of care. These themes support current knowledge and identify wider concerns around the hospital environment and recovery. This study may inform the development of future interventions aimed at reducing preoperative anxiety.


Asunto(s)
Ansiedad/psicología , Periodo Preoperatorio , Adolescente , Adulto , Anciano , Ansiedad/diagnóstico , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Nueva Zelanda , Investigación Cualitativa , Adulto Joven
19.
Psychol Health ; 34(2): 129-146, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30450974

RESUMEN

OBJECTIVE: Preoperative anxiety is often assessed using general anxiety measures; existing specific measures might lack content coverage and/or are not psychometrically validated. This study aimed to develop a new self-report measure of surgery-specific anxiety and test its psychometric properties. DESIGN: The surgical anxiety questionnaire (SAQ) was developed from themes identified in qualitative research and reviewed by an interdisciplinary expert team. It was administered preoperatively to 135 patients (56% female, mean age 51) on the day of surgery alongside additional measures of preoperative anxiety, state anxiety, perceived stress, depression and social desirability. Follow-up assessment was conducted immediately post-surgery and two weeks post-surgery (n = 114) to examine recovery and predictive validity of the scale. RESULTS: Factor analysis revealed a three component structure, including: concerns about health (six items), concerns about recovery (four items) and concerns about procedures (four items). Three additional items of relatively high concern were retained in the total score (17 items). The SAQ displayed good reliability, validity (content, construct and predictive) and adequate overall psychometric properties. CONCLUSIONS: Preliminary results suggest that the SAQ is a promising tool for measuring preoperative anxiety and predicting recovery. Recommendations for future research include employing a confirmatory factor analysis and examining test-retest reliability.


Asunto(s)
Ansiedad/diagnóstico , Procedimientos Quirúrgicos Operativos/psicología , Encuestas y Cuestionarios , Anciano , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Reproducibilidad de los Resultados
20.
MAbs ; 10(1): 81-94, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28991504

RESUMEN

A large body of data exists demonstrating that neonatal Fc receptor (FcRn) binding of an IgG via its Fc CH2-CH3 interface trends with the pharmacokinetics (PK) of IgG. We have observed that PK of IgG molecules vary widely, even when they share identical Fc domains. This led us to hypothesize that domains distal from the Fc could contribute to FcRn binding and affect PK. In this study, we explored the role of these IgG domains in altering the affinity between IgG and FcRn. Using a surface plasmon resonance-based assay developed to examine the steady-state binding affinity (KD) of IgG molecules to FcRn, we dissected the contributions of IgG domains in modulating the affinity between FcRn and IgG. Through analysis of a broad collection of therapeutic antibodies containing more than 50 unique IgG molecules, we demonstrated that variable domains, and in particular complementarity-determining regions (CDRs), significantly alter binding affinity to FcRn in vitro. Furthermore, a panel of IgG molecules differing only by 1-5 mutations in CDRs altered binding affinity to FcRn in vitro, by up to 79-fold, and the affinity values correlated with calculated isoelectric point values of both variable domains and CDR-L3. In addition, tighter affinity values trend with faster in vivo clearance of a set of IgG molecules differing only by 1-3 mutations in human FcRn transgenic mice. Understanding the role of CDRs in modulation of IgG affinity to FcRn in vitro and their effect on PK of IgG may have far-reaching implications in the optimization of IgG therapeutics.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Regiones Determinantes de Complementariedad/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Inmunoglobulina G/metabolismo , Receptores Fc/metabolismo , Animales , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Sitios de Unión de Anticuerpos , Células CHO , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/inmunología , Cricetulus , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Masculino , Ratones Transgénicos , Mutación , Variantes Farmacogenómicas , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Receptores Fc/genética , Receptores Fc/inmunología
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