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1.
J Healthc Manag ; 69(1): 12-28, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38175533

RESUMEN

GOAL: Clinician stress and resilience have been the subjects of significant research and interest in the past several decades. We aimed to understand the factors that contribute to clinician stress and resilience in order to appropriately guide potential interventions. METHODS: We conducted a scoping review (n = 42) of published reviews of research on clinician distress and resilience using the methodology of Peters and colleagues (2020). Our team examined these reviews using the National Academy of Medicine's framework for clinician well-being and resilience. PRINCIPAL FINDINGS: We found that organizational factors, learning/practice environment, and healthcare responsibilities were three of the top four factors identified in the reviews as contributing to clinician distress. Learning/practice environment and organizational factors were two of the top four factors identified in the reviews as contributing to their resilience. PRACTICAL APPLICATIONS: Clinicians continue to face numerous external challenges that complicate their work. Further research, practice, and policy changes are indicated to improve practice environments for healthcare clinicians. Healthcare leaders need to promote resources for organizational and system-level changes to improve clinician well-being.


Asunto(s)
Personal de Salud , Estrés Laboral , Resiliencia Psicológica , Humanos , Personal de Salud/psicología
2.
Carbohydr Res ; 534: 108977, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37949033

RESUMEN

Herein, we report the total synthesis of the trisaccharide repeating unit of the O-antigen of Actinobacillus actinomycetemcomitans serotype f. The trisaccharide comprising of α-(1-2) and α-(1-3)-linked L-rhamnopyranosides backbone with the latter rhamnose containing a branching N-acetyl-d-galactosaminopyranoside at the C2-O via a ß-glycosidic bond was synthesized by two methods. Initially, the protected trisaccharide has been synthesized by step-wise assembly of the monosaccharide building blocks and subsequently the former was synthesized by the one-pot assembly of the latter components. The synthesized trisaccharide contains an aminoethyl linker appended as an O-glycoside at the reducing end, thereby providing scope for further conjugation for different applications.


Asunto(s)
Aggregatibacter actinomycetemcomitans , Antígenos O , Antígenos O/química , Aggregatibacter actinomycetemcomitans/química , Serogrupo , Monosacáridos , Glicósidos , Trisacáridos
3.
Carbohydr Res ; 521: 108669, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36099720

RESUMEN

Synthetic conjugate vaccines are an important area of research for the prevention and occurrence of diseases caused by Gram-negative bacteria. For the development of such vaccines, access to the pure and homogeneous oligosaccharide fragments of the bacterial cell surface polysaccharides are necessary. Stenotrophomonas maltophilia is a typical opportunistic Gram-negative bacteria that causes severe pulmonary and other infections; often in hospitalized patients. With the emergence of multidrug resistant strains and increased virulence, new therapeutic strategies are needed to combat the threat. Herein, we report the syntheses of the trisaccharide repeating unit of S. maltophilia O6 antigen through stepwise and one-pot assemblies of the trisaccharide. The target trisaccharide was appended with a 2-aminoethyl linker that could provide the opportunity for conjugation to carrier proteins for the synthesis of vaccine candidates.


Asunto(s)
Stenotrophomonas maltophilia , Antibacterianos/metabolismo , Proteínas Portadoras/metabolismo , Humanos , Polisacáridos Bacterianos/metabolismo , Stenotrophomonas maltophilia/metabolismo , Trisacáridos/metabolismo , Vacunas Conjugadas
4.
J Thorac Oncol ; 17(3): 434-445, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34800700

RESUMEN

INTRODUCTION: First-line therapy for patients with metastatic NSCLC includes checkpoint inhibitor monotherapy, dual checkpoint inhibition, or combination with chemotherapy. We compared outcomes with combination chemoimmunotherapy versus dual checkpoint inhibition as first-line treatment for patients with metastatic NSCLC. METHODS: This open-label, randomized clinical trial was conducted at 44 sites in Canada and Australia. Patients with treatment-naive, metastatic NSCLC without sensitizing EGFR or ALK alterations were randomized (1:1) to receive treatment with durvalumab plus tremelimumab with or without platinum-doublet chemotherapy. The primary end point was overall survival (OS). Secondary end points were progression-free survival, overall response rate, and safety. RESULTS: A total of 301 patients were randomized. Median OS was 16.6 months (95% confidence interval [CI]: 12.6-19.1) with chemotherapy plus immunotherapy and 14.1 months (95% CI: 10.6-18.3) with immunotherapy (hazard ratio = 0.88, 90% CI: 0.67-1.16, p = 0.46). Median progression-free survival with chemotherapy plus immunotherapy was 7.7 months (95% CI: 5.5-8.5) and 3.2 months (95% CI: 2.7-5.1) with immunotherapy (hazard ratio = 0.67, 95% CI: 0.52-0.88). The overall response rate with chemoimmunotherapy was 42.4% and 29.3% with immunotherapy (adjusted OR = 1.69, 95% CI: 1.04-2.76). The percentage of patients with grade 3 or higher adverse events was 82% in the chemotherapy plus immunotherapy group and 70% in the immunotherapy group. Exploratory analyses of programmed death-ligand 1 expression and blood-based tumor mutation burden revealed no differential treatment effect on OS. CONCLUSIONS: The addition of chemotherapy to durvalumab plus tremelimumab in the first-line treatment of stage IV NSCLC did not improve survival compared with durvalumab plus tremelimumab alone. Further study is warranted to identify patients that benefit from initial immunotherapy alone versus combination chemotherapy plus immunotherapy as first-line treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Anticuerpos Monoclonales , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/patología , Humanos , Neoplasias Pulmonares/patología , Platino (Metal)/uso terapéutico
5.
Comput Biol Med ; 141: 104822, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34548173

RESUMEN

Retinal optical coherence tomography (OCT) with intraretinal layer segmentation is increasingly used not only in ophthalmology but also for neurological diseases such as multiple sclerosis (MS). Signal quality influences segmentation results, and high-quality OCT images are needed for accurate segmentation and quantification of subtle intraretinal layer changes. Among others, OCT image quality depends on the ability to focus, patient compliance and operator skills. Current criteria for OCT quality define acceptable image quality, but depend on manual rating by experienced graders and are time consuming and subjective. In this paper, we propose and validate a standardized, grader-independent, real-time feedback system for automatic quality assessment of retinal OCT images. We defined image quality criteria for scan centering, signal quality and image completeness based on published quality criteria and typical artifacts identified by experienced graders when inspecting OCT images. We then trained modular neural networks on OCT data with manual quality grading to analyze image quality features. Quality analysis by a combination of these trained networks generates a comprehensive quality report containing quantitative results. We validated the approach against quality assessment according to the OSCAR-IB criteria by an experienced grader. Here, 100 OCT files with volume, circular and radial scans, centered on optic nerve head and macula, were analyzed and classified. A specificity of 0.96, a sensitivity of 0.97 and an accuracy of 0.97 as well as a Matthews correlation coefficient of 0.93 indicate a high rate of correct classification. Our method shows promising results in comparison to manual OCT grading and may be useful for real-time image quality analysis or analysis of large data sets, supporting standardized application of image quality criteria.


Asunto(s)
Disco Óptico , Tomografía de Coherencia Óptica , Humanos , Redes Neurales de la Computación , Control de Calidad , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos
6.
Artículo en Inglés | MEDLINE | ID: mdl-32576604

RESUMEN

OBJECTIVE: To investigate disease-specific foveal shape changes in patients with neuromyelitis optica spectrum disorders (NMOSDs) using foveal morphometry. METHODS: This cross-sectional study included macular spectral domain optical coherence tomography scans of 52 eyes from 28 patients with aquaporin-4 immunoglobulin G (AQP4-IgG)-seropositive NMOSD, 116 eyes from 60 patients with MS, and 123 eyes from 62 healthy controls (HCs), retrospectively, and an independent confirmatory cohort comprised 33/33 patients with NMOSD/MS. The fovea was characterized using 3D foveal morphometry. We included peripapillary retinal nerve fiber layer (pRNFL) thickness and combined macular ganglion cell and inner plexiform layer (GCIPL) volume to account for optic neuritis (ON)-related neuroaxonal damage. RESULTS: Group comparison showed significant differences compared with HC in the majority of foveal shape parameters in NMOSD, but not MS. Pit flat disk area, average pit flat disk diameter, inner rim volume, and major slope disk length, as selected parameters, showed differences between NMOSD and MS (p value = 0.017, 0.002, 0.005, and 0.033, respectively). This effect was independent of ON. Area under the curve was between 0.7 and 0.8 (receiver operating characteristic curve) for discriminating between NMOSD and MS. Pit flat disk area and average pit flat disk diameter changes independent of ON were confirmed in an independent cohort. CONCLUSIONS: Foveal morphometry reveals a wider and flatter fovea in NMOSD in comparison to MS and HC. Comparison to MS and accounting for ON suggest this effect to be at least in part independent of ON. This supports a primary retinopathy in AQP4-IgG-seropositive NMOSD.


Asunto(s)
Acuaporina 4/inmunología , Fóvea Central/patología , Esclerosis Múltiple/patología , Neuromielitis Óptica/inmunología , Neuromielitis Óptica/patología , Adulto , Estudios Transversales , Femenino , Fóvea Central/diagnóstico por imagen , Humanos , Inmunoglobulina G , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico por imagen , Neuromielitis Óptica/diagnóstico por imagen , Estudios Retrospectivos , Tomografía de Coherencia Óptica
7.
Environ Monit Assess ; 191(9): 576, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31428877

RESUMEN

Evolution of submicron particles in terms of particle number concentration and mobility-equivalent diameter was measured during Diwali festival-specific intensive pyrotechnic displays in Varanasi over central Indo-Gangetic Plain (IGP). A scanning mobility particle sizer coupled with an optical particle sizer was used to fit in an overlapping size range, and particle number concentration was analyzed to have an insight into the new particle formation and subsequent evolution of particles from nucleation to accumulation mode. Further, variation in black carbon (BC) concentration and aerosol ionic composition was measured simultaneously. Frequent fluctuation in particle number concentration in and around Diwali festival was evidenced, primarily influenced by local emission sources and meteorology, with three distinct peaks in number concentrations (dN/dlogDp, 3.1-4.5 × 104 cm3) coinciding well with peak firework emission period (18:00-23:00 h). Submicron particle size distribution revealed a single peak covering a size range of 80-130 nm, and for all instances, number concentration maximum coincided with geometric mean minimum, indicating the emission primarily in the ultrafine range (< 0.1 µm). Interestingly, during peak firework emissions, besides rise in accumulation mode, an event of new particle formation was identified with increase in nucleation and small Aitken mode, before being dispersed to background aerosols. On an integral scale, a clear distinction was noted between a normal and an episodic event, with a definite shift in the formation of ultrafine particles compared with the accumulation mode. The BC diurnal profile was typical, with a prominent nocturnal peak (12.0 ± 3.9 µg m-3) corresponding to a decrease in the boundary layer height. A slight variation in maximum BC concentration (16.8 µg m-3) was noted in the night of the event coinciding well with firework emissions. An increase in some specific ionic species was also noted in combination with an increase in the overall cation to anion ratio, which was explained in terms of heterogeneous transformation of NOx and catalytic conversion of SO2. Graphical abstract Time-resolved evolution of particle size distribution during normal and episodic events.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Sustancias Explosivas , Material Particulado/análisis , Vacaciones y Feriados , India , Tamaño de la Partícula , Hollín/análisis , Factores de Tiempo
8.
Planta ; 249(6): 1987-1996, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30903269

RESUMEN

MAIN CONCLUSION: Amino acid sequence and crystal structure analyses of Tma12, an insecticidal protein isolated from the fern Tectaria macrodonta, identify it as a carbohydrate-binding protein belonging to the AA10 family of lytic polysaccharide monooxygenases, and provide the first evidence of AA10 proteins in plants. Tma12, isolated from the fern Tectaria macrodonta, is a next-generation insecticidal protein. Transgenic cotton expressing Tma12 exhibits resistance against whitefly and viral diseases. Beside its insecticidal property, the structure and function of Tma12 are unknown. This limits understanding of the insecticidal mechanism of the protein and targeted improvement in its efficacy. Here we report the amino acid sequence analysis and the crystal structure of Tma12, suggesting that it is possibly a lytic polysaccharide monooxygenase (LPMO) of the AA10 family. Amino acid sequence of Tma12 shows 45% identity with a cellulolytic LPMO of Streptomyces coelicolor. The crystal structure of Tma12, obtained at 2.2 Å resolution, possesses all the major structural characteristics of AA10 LPMOs. A H2O2-based enzymatic assay also supports this finding. It is the first report of the occurrence of LPMO-like protein in a plant. The two facts that Tma12 possesses insecticidal activity and shows structural similarity with LPMOs collectively advocate exploration of microbial LPMOs for insecticidal potential.


Asunto(s)
Helechos/enzimología , Hemípteros/efectos de los fármacos , Insecticidas/metabolismo , Oxigenasas de Función Mixta/metabolismo , Polisacáridos/metabolismo , Secuencia de Aminoácidos , Animales , Helechos/química , Helechos/genética , Gossypium/enzimología , Gossypium/genética , Gossypium/fisiología , Peróxido de Hidrógeno/metabolismo , Insecticidas/farmacología , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Receptores de Superficie Celular/química , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Alineación de Secuencia
9.
Dis Colon Rectum ; 53(10): 1432-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20847626

RESUMEN

BACKGROUND: Adjuvant therapy results in significant improvement in survival of patients with high-risk colorectal cancer. Little is known about the significance of timing and early discontinuation of adjuvant treatment in such patients. Our study aims to determine the prognostic impact of timing and completion of adjuvant therapy in patients with high-risk colorectal cancer. METHODS: Medical records of patients with stage III colon and stage II/III rectal cancer diagnosed between 1993 and 2000 in the province of Saskatchewan were reviewed. Cox proportional hazards models were used to analyze the impact of timing and completion of adjuvant therapy on survival. RESULTS: Six hundred sixty-three eligible patients with a median age of 66 years were identified. Sixty-five percent patients received adjuvant <56 days after surgery and 79% patients completed planned treatment. Median follow-up was 54.6 months. Five-year disease-free survival and overall survival of patients who received adjuvant therapy <56 days after surgery was 54.6% and 59.5%, respectively, compared with 51.9% and 57.1%, respectively, of patients who received therapy ≥56 days after surgery (P = NS). The five-year disease disease-free survival and overall survival of patients who completed planned treatment was 56.7% and 62.3%, respectively, compared with 42.1% and 45%, respectively, of patients who required early treatment discontinuation (P < .0001). On multivariate analysis, age ≥65 years, T4 tumor, grade 3 cancer, node-positive disease, rectal tumor, and early treatment discontinuation were identified as poor prognostic factors. CONCLUSIONS: Although time to adjuvant therapy following surgical resection did not impact the outcomes, failure to complete planned therapy was associated with adverse prognosis.


Asunto(s)
Neoplasias del Colon/mortalidad , Neoplasias del Colon/terapia , Neoplasias del Recto/mortalidad , Neoplasias del Recto/terapia , Privación de Tratamiento , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Neoplasias del Colon/patología , Terapia Combinada , Supervivencia sin Enfermedad , Relación Dosis-Respuesta en la Radiación , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Neoplasias del Recto/patología , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo
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