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1.
Molecules ; 27(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35408619

RESUMO

Pentacyclic triterpenoic acids (betulinic, oleanolic, ursolic, and platanic acid) were selected and subjected to acetylation followed by the formation of amides derived from either piperazine or homopiperazine. These amides were coupled with either rhodamine B or rhodamine 101. All of these compounds were screened for their cytotoxic activity in SRB assays. As a result, the cytotoxicity of the parent acids was low but increased slightly upon their acetylation while a significant increase in cytotoxicity was observed for piperazinyl and homopiperazinyl amides. A tremendous improvement in cytotoxicity was observed; however, for the rhodamine B and rhodamine 101 conjugates, and compound 27, an ursolic acid derived homopiperazinyl amide holding a rhodamine 101 residue showed an EC50 = 0.05 µM for A2780 ovarian cancer cells while being less cytotoxic for non-malignant fibroblasts. To date, the rhodamine 101 derivatives presented here are the first examples of triterpene derivatives holding a rhodamine residue different from rhodamine B.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Triterpenos , Amidas/química , Amidas/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Rodaminas/química , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/farmacologia
2.
BMC Musculoskelet Disord ; 23(1): 183, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35219313

RESUMO

BACKGROUND: Shoulder pain is a prevalent and often long-lasting musculoskeletal disorder. The overall prognosis of shoulder pain is highly variable with 40-50% of patients reporting persistent pain 6-12 months after consulting a clinician. The evidence for psychological prognostic factors for patients with shoulder pain is inconsistent. Therefore, the objective of this study was to investigate the association between fear of movement and emotional distress at presentation and self-reported disability over one year of follow-up. METHODS: This is a prospective cohort study of consecutive patients referred to secondary outpatient care due to shoulder pain. Consenting patients underwent a physical examination and completed a comprehensive questionnaire at baseline, three months-, and one-year follow-up. Associations between baseline fear of movement (0-10) or emotional distress (1-4), respectively, and patient reported disability measured using Quick Disability of the Arm and Shoulder (QuickDASH, 0-100) over one year were analyzed with linear mixed-effects models (LMM) for repeated measures (baseline, 3 months and 1 year), adjusting for established prognostic factors. RESULTS: A total of 138 patients were recruited between March 2015 and January 2018, with response rates of 84.7% (n = 117) and 79.7% (n = 100) at three months and one year, respectively. Adjusted associations revealed that for every point increase in baseline fear of movement, the QuickDASH score increased (worsened) by 1.10 points (95% CI 0.2-2.0) over the follow-up year. For every point increase in baseline emotional distress, the QuickDASH score increased by 19.9 points (95% CI 13.9-25.9) from baseline over the follow-up year. CONCLUSION: Higher fear of movement and emotional distress scores at baseline were significantly associated with higher disability over one year in patients with shoulder pain referred to secondary care. Our study indicates that these psychological factors affect prognosis and should be considered by clinicians and researchers working with patients with shoulder pain.


Assuntos
Angústia Psicológica , Dor de Ombro , Avaliação da Deficiência , Medo , Humanos , Medição da Dor , Prognóstico , Estudos Prospectivos , Dor de Ombro/diagnóstico , Dor de Ombro/psicologia
3.
Molecules ; 26(23)2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34885800

RESUMO

Head-to-tail cyclized bacteriocins are ribosomally synthesized antimicrobial peptides that are defined by peptide backbone cyclization involving the N- and C- terminal amino acids. Their cyclic nature and overall three-dimensional fold confer superior stability against extreme pH and temperature conditions, and protease degradation. Most of the characterized head-to-tail cyclized bacteriocins were discovered through a traditional approach that involved the screening of bacterial isolates for antimicrobial activity and subsequent isolation and characterization of the active molecule. In this study, we performed genome mining using transporter protein sequences associated with experimentally validated head-to-tail cyclized bacteriocins as driver sequences to search for novel bacteriocins. Biosynthetic gene cluster analysis was then performed to select the high probability functional gene clusters. A total of 387 producer strains that encode putative head-to-tail cyclized bacteriocins were identified. Sequence and phylogenetic analyses revealed that this class of bacteriocins is more diverse than previously thought. Furthermore, our genome mining strategy captured hits that were not identified in precursor-based bioprospecting, showcasing the utility of this approach to expanding the repertoire of head-to-tail cyclized bacteriocins. This work sets the stage for future isolation of novel head-to-tail cyclized bacteriocins to serve as possible alternatives to traditional antibiotics and potentially help address the increasing threat posed by resistant pathogens.


Assuntos
Peptídeos Antimicrobianos/genética , Bactérias/genética , Bacteriocinas/genética , Genoma Bacteriano , Antibacterianos/química , Peptídeos Antimicrobianos/química , Bactérias/química , Bacteriocinas/química , Ciclização , Família Multigênica , Filogenia
4.
BMC Psychiatry ; 21(1): 473, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34579676

RESUMO

BACKGROUND: This study quantifies the frequency of adverse events (AEs) experienced by psychiatric patients while boarded in the emergency department (ED) and describes those events over a broad range of categories. METHODS: A retrospective chart review (RCR) of adult psychiatric patients aged 18-55 presenting to one of four Calgary EDs (Foothills Medical Centre (FMC), the Peter Lougheed Centre (PLC), the Rockyview General Hospital (RGH), and South Health Campus (SHC)) who were subsequently admitted to an inpatient psychiatric unit between January 1, 2019 and May 15, 2019 were eligible for review. A test of association was used to determine the odds of an independent variable being associated with an adverse event. RESULTS: During the study time period, 1862 adult patients were admitted from EDs (city wide) to the psychiatry service. Of the 200 charts reviewed, the average boarding time was 23.5 h with an average total ED length of stay of 31 h for all presentations within the sample. Those who experienced an AE while boarded in the ED had a significantly prolonged average boarding time (35 h) compared to those who did not experience one (6.5 h) (p = 0.005). CONCLUSIONS: The length of time a patient is in the emergency department and the length of time a patient is boarded after admission significantly increases the odds that the patient will experience an AE while in the ED. Other significant factors associated with AEs include the type of admission and the hospital the patient was admitted from.


Assuntos
Serviço Hospitalar de Emergência , Hospitalização , Adulto , Humanos , Pacientes Internados , Tempo de Internação , Admissão do Paciente , Estudos Retrospectivos
5.
Pilot Feasibility Stud ; 7(1): 31, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33494821

RESUMO

BACKGROUND: Exercise is recommended for patients with subacromial pain. It has been suggested that good exercise adherence improves clinical outcomes. Despite this, little attention has been paid to the need for behavioural frameworks to enhance adherence to home exercise programmes for patients with subacromial pain. METHODS: A feasibility study with pre-post design was used. Participants aged > 18 years, with subacromial pain, who had received conservative treatment during the past 6 months, were recruited. The Ad-Shoulder intervention consisted of 1-5 individual sessions provided over 3 months and was based on 5 self-management skills, which aimed to enhance the patients' self-efficacy and adherence to self-managed exercises. The primary objectives were assessed according to predefined progression criteria: (1) the recruitment rate (10 patients enrolled within 12 weeks), (2) follow-up rate (≥ 80% on all self-reported measures), (3) objective physical activity measures (≥ 80% of participants would contribute valid data at each time point), (4) adherence with the self-managed exercises (≥ 80% of the participants would adhere to ≥ 80% of the assigned home exercise programme), (5) fidelity of the delivery of the intervention (the therapists delivered the intervention according to the protocol) and (6) adverse events (< 30% would report adverse events (including mild)). The results were reported using descriptive statistics. RESULTS: Eleven patients were recruited during 16 weeks. Ten patients completed the self-reported measures at baseline and week 12. Objective physical activity measures were successfully obtained for 100% (11/11) at baseline, 64% (7/11) at week six and 82% at week 12. Fifty-five percent (6/11) of the participants satisfactorily completed at least 80% of their home exercise programme. All sessions were delivered according to the protocol. None of the patients reported any adverse events. CONCLUSIONS: Objective physical activity data measures at baseline and week 12, follow-up, the physiotherapists' fidelity to the intervention and adverse events met our pre-specified progression criteria. Recruitment and adherence to the self-managed exercise programme were both below the anticipated level. Further intervention development is necessary to understand whether adherence to the self-managed exercises could be enhanced and additional methods of recruitment would need to be considered, including additional recruitment sites, in any planning for a future main trial. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04190836 , Registered December 9, 2019-retrospectively registered.

6.
Eur J Med Chem ; 209: 112920, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049606

RESUMO

Safirinium P and Q fluorescence labels were synthesized and conjugated with spacered triterpenoic acids to access hybrid structures. While the parent safirinium compounds were not cytotoxic at all, many triterpenoid safirinium P and Q conjugates showed moderate cytotoxicity. An exception, however, was safirinium P derived compound 30 holding low EC50 = 5.4 µM (for A375 cells) to EC50 = 7.5 µM (for FaDu cells) as well as EC50 = 6.6 µM for non-malignant fibroblasts NIH 3T3. Fluorescence imaging showed that the safirinium core structures cannot enter the cells (not even after a prolonged incubation time of 24 h), while the conjugates (as exemplified for 30) are accumulating in the endoplasmic reticulum but not in the mitochondria. The development of safirinium-hybrids targeting the endoplasmic reticulum can be regarded as a promising strategy in the development of cytotoxic agents.


Assuntos
Antineoplásicos/farmacologia , Compostos Azo/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Antineoplásicos/síntese química , Compostos Azo/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Corantes Fluorescentes/química , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Terapia de Alvo Molecular , Imagem Óptica , Piperazina/química , Relação Estrutura-Atividade , Triterpenos/síntese química
7.
BMJ Open Sport Exerc Med ; 5(1): e000656, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31908837

RESUMO

BACKGROUND: Exercise interventions are frequently recommended for patients with rotator cuff disease, but poor content reporting in clinical trials of exercise limits interpretation and replication of trials and clinicians' ability to deliver effective exercise protocols. The Consensus on Exercise Reporting Template (CERT) was developed to address this problem. OBJECTIVE: To assess completeness of content reporting of exercise interventions in randomised controlled trials for patients with rotator cuff disease and the inter-rater reliability of the CERT. DESIGN: Critical appraisal. METHODS: Independent pairs of reviewers applied the CERT to all 34 exercise trials from the most recent Cochrane Review evaluating the effect of manual therapy and exercise for patients with rotator cuff disease. We used the CERT Explanation and Elaboration Statement to guide assessment of whether each of the 19-item criteria were clearly described (score 0-19; higher scores indicate better reporting). Percentage agreement and the prevalence and bias adjusted kappa (PABAK) coefficient were used to measure inter-rater reliability. RESULTS: The median CERT score was 5 (range 0-16). Percentage agreement was high for 15 items and acceptable for 4 items. The PABAK coefficient indicated excellent (5 items), substantial (11 items) and moderate (3 items) inter-rater agreement. CONCLUSION: The description of exercise interventions for patients with rotator cuff disease in published trials is poorly reported. Overall, the inter-rater reliability of the CERT is high/acceptable. We strongly encourage journals to mandate use of the CERT for papers reporting trial protocols and results investigating exercise interventions.

8.
Phys Chem Chem Phys ; 20(19): 13419-13429, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29722404

RESUMO

Ultrasmall silicon carbide nanoparticles (SiC USNPs) are very promising biomarkers for developing new applications in diagnostics, cell monitoring or drug delivery, even though their interaction with biological molecules such as different proteins has not yet been investigated in detail. In this study, the biological behaviour of SiC USNPs in a medium modeling a living organism was investigated in detail through the dependence of the fluorescence on interactions between bovine serum albumin (BSA) and SiC USNPs. The interaction shows transient nanoparticle-protein associations due to the restricted diffusion behaviour of the nanoparticles in the vicinity of a protein. The transient association manifests in a complex fluorescence quenching mechanism where the dynamic component was dominated by Förster resonance energy transfer. By studying SiC nanoparticles of different sizes, it can be concluded that the transient effect is an ultrasmall nanoparticle behaviour.


Assuntos
Compostos Inorgânicos de Carbono/química , Corantes Fluorescentes/química , Nanopartículas/química , Soroalbumina Bovina/química , Compostos de Silício/química , Animais , Sítios de Ligação , Biomarcadores/química , Bovinos , Transferência Ressonante de Energia de Fluorescência , Cinética , Tamanho da Partícula , Ligação Proteica , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície , Termodinâmica
9.
J Comp Neurol ; 469(2): 275-97, 2004 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-14694539

RESUMO

The nucleus isthmi pars magnocellularis (Imc) and pars parvocellularis (Ipc) influence the receptive field structure of neurons in the optic tectum (TeO). To understand better the anatomical substrate of isthmotectal interactions, neuronal morphology and connections of Imc were examined in chicks (Gallus gallus). Cholera toxin B injection into TeO demonstrated a coarse topographical projection from TeO upon Imc. Retrogradely labeled neurons were scattered throughout Imc and in low density within the zone of anterogradely labeled terminals, suggesting a heterotopic projection from Imc upon TeO. This organization differed from the precise homotopic reciprocal connections of Ipc and the nucleus isthmi pars semilunaris (SLu) with TeO. By using slice preparations, extracellular biotinylated dextran amine injections demonstrated a dense projection from most neurons in Imc upon both Ipc and SLu. Intracellular filling of Imc neurons with biocytin revealed two cell types. The most common, Imc-Is, formed a widely ramifying axonal field in both Ipc and SLu, without obvious topography. A less frequently observed cell type, Imc-Te, formed a widely ramifying terminal field in layers 10-12 of TeO. No neurons were found to project upon both Ipc/SLu and TeO. Both types possessed local axon collaterals and flat dendritic fields oriented parallel to the long axis of Imc. Imc neurons contain glutamic acid decarboxylase, which is consistent with Imc participating in center-surround or other wide-field inhibitory isthmotectal interactions. The laminar and columnar pattern of isthmotectal terminals also suggests a means of interacting with multiple tectofugal pathways, including the stratified subpopulations of tectorotundal neurons participating in motion detection.


Assuntos
Biotina/análogos & derivados , Galinhas/anatomia & histologia , Lisina/análogos & derivados , Mesencéfalo/citologia , Vias Neurais/citologia , Neurônios/citologia , Colículos Superiores/citologia , Animais , Axônios/fisiologia , Axônios/ultraestrutura , Galinhas/fisiologia , Toxina da Cólera , Dendritos/fisiologia , Dendritos/ultraestrutura , Dextranos , Glutamato Descarboxilase/metabolismo , Imuno-Histoquímica , Mesencéfalo/fisiologia , Percepção de Movimento/fisiologia , Inibição Neural/fisiologia , Vias Neurais/fisiologia , Neurônios/fisiologia , Colículos Superiores/fisiologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo
10.
J Comp Neurol ; 463(3): 317-40, 2003 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-12820165

RESUMO

The retinofugal pathways in the California ground squirrel, Spermophilus beecheyi, were mapped after intravitreal injections of cholera toxin B-subunit. The results of the current study are consistent with work in other mammals and provide new details relevant to the organization and evolution of the visual system. All retinorecipient nuclei received bilateral input, with a contralateral predominance. The suprachiasmatic nucleus is heavily innervated, and sparse terminals were noted in other hypothalamic areas. In addition to the interstitial, medial, lateral, and dorsal terminal nuclei, a few fibers of the accessory optic tract may enter the ventral lateral geniculate and the nucleus of the optic tract, though this innervation may not derive from the same ganglion cells innervating the accessory optic nuclei. Retinal terminals are found in the intergeniculate leaflet and the "dorsal cap" of the ventral lateral geniculate. Retinal fibers pass rostrally from the dorsal cap toward the anterodorsal thalamus, confirming a projection described in the tree shrew and monkeys. Retinal termination patterns in the dorsal lateral geniculate reveal a hexilaminate organization of alternating ipsilateral and contralateral input. Variations in terminal morphology suggest that sublayers receive input from distinct ganglion cell types and that laminar comparisons can be made with primates. Finally, terminal patterns in the superior colliculus reveal a dense, highly ordered columnar organization supporting functional properties of tectal receptive fields. All the visual structures in the ground squirrel are large and well differentiated, making the sciurid visual system an accessible rodent model for comparing visual processing with that in other diurnal vertebrates.


Assuntos
Retina/citologia , Sciuridae/anatomia & histologia , Vias Visuais/anatomia & histologia , Animais , Toxina da Cólera , Feminino , Corpos Geniculados/anatomia & histologia , Masculino , Colículos Superiores/anatomia & histologia , Núcleo Supraquiasmático/anatomia & histologia
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