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1.
Arch Pathol Lab Med ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38452805

RESUMO

CONTEXT.­: Mutant KRAS is the main oncogenic driver in pancreatic ductal adenocarcinomas (PDACs). However, the clinical and phenotypic implications of harboring different mutant KRAS alleles remain poorly understood. OBJECTIVE.­: To characterize the potential morphologic and clinical outcome differences in PDACs harboring distinct mutant KRAS alleles. DESIGN.­: Cohort 1 consisted of 127 primary conventional PDACs with no neoadjuvant therapy, excluding colloid/mucinous, adenosquamous, undifferentiated, and intraductal papillary mucinous neoplasm-associated carcinomas, for which an in-house 42-gene mutational panel had been performed. A morphologic classification system was devised wherein each tumor was assigned as conventional, papillary/large duct (P+LD, defined as neoplastic glands with papillary structure and/or with length ≥0.5 mm), or poorly differentiated (when the aforementioned component was 60% or more of the tumor). Cohort 2 was a cohort of 88 PDACs in The Cancer Genome Atlas, which were similarly analyzed. RESULTS.­: In both cohorts, there was significant enrichment of P+LD morphology in PDACs with KRAS G12V and G12R compared with G12D. In the entire combined cohort, Kaplan-Meier analyses showed longer overall survival (OS) with KRAS G12R as compared with G12D (median OS of 1255 versus 682 days, P = .03) and in patients whose PDACs displayed P+LD morphology as compared with conventional morphology (median OS of 1175 versus 684 days, P = .04). In the adjuvant-only subset, KRAS G12R had the longest OS compared with G12D, G12V, and other alleles (median OS unreached/undefined versus 1009, 1129, and 1222 days, respectively). CONCLUSIONS.­: PDACs with different mutant KRAS alleles are associated with distinct morphologies and clinical outcomes, with KRAS G12R allele associated with P+LD morphology and longer OS when compared with G12D using Kaplan-Meier studies.

2.
Front Immunol ; 14: 1230534, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545516

RESUMO

Introduction: Soft tissue sarcomas (STS) are rare, heterogenous malignancies with an unmet need for novel immunotherapies. Tumor infiltrating lymphocytes (TILs) have been linked with favorable outcomes in STS patients, though the contribution of natural killer (NK) cells and spatial relationships of TILs with MHC-I expressing cells lacks detailed characterization. Experimental design: Using archived and prospectively collected specimens, we evaluated intratumoral NK cells by immunohistochemistry (IHC), flow cytometry, and immunofluorescence (IF). We assessed spatial localization of NK and T cells by multiplex IF, analyzing the effects of MHC-I expression status on NK and T cell clustering. Results: Both intratumoral NKp46 and CD56dim expression were associated with significantly improved overall survival (P=0.05), while higher infiltrates of CD56bright NK cells predicted a worse prognosis (P=0.05). The presence of intratumoral NK cells was inversely proportional to CD3+ T cells. Spatial analyses showed NK cells preferentially clustering close to other NK cells with sparse CD3+ T and CD8+ T cells in range (P<0.0001). Additionally, CD3+ T and CD8+ T cells showed significantly greater co-localization with MHC-I+ cells, compared to NK cells (P<0.0001). After neoadjuvant radiotherapy, there was greater CD8 clustering, while after neoadjuvant chemotherapy, there was overall lower TIL clustering. Conclusion: Intratumoral NK cells are prognostic in STS and localize closer to MHC-I- cells than T cells. Although both NK and T cells are associated with improved survival in STS, their differential distribution in the TME based on MHC-I expression status may serve as a biomarker for improved immunotherapy treatment selection.


Assuntos
Linfócitos T CD8-Positivos , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Linfócitos T CD8-Positivos/imunologia , Células Matadoras Naturais/imunologia , Prognóstico , Sarcoma/imunologia , Sarcoma/terapia , Neoplasias de Tecidos Moles/imunologia , Neoplasias de Tecidos Moles/terapia
3.
Cureus ; 15(6): e40292, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37448384

RESUMO

Background Arthroscopic repair of glenohumeral instability is becoming an increasingly common procedure. These repairs can be undertaken using knot-tying and knotless suture anchors; there is currently no clear consensus in the literature about what type of repair is most cost-effective and provides superior outcomes. The purpose of this study is to examine postoperative outcomes of patients undergoing arthroscopic anteroinferior labral repair (AALR) with either knot-tying or knotless anchors. Methods A single institution retrospective observational cohort study of 122 patients undergoing AALR from January 2014 to June 2021 was conducted. Univariate statistics were used to assess differences in demographics, operative characteristics, and postoperative outcomes between repair types; multivariate analysis was used to evaluate risk factors for recurrent instability and reoperation. Results Patients undergoing AALR with knotless anchors had a shorter case duration than those with knot-tying anchors (112.64 vs. 89.86 minutes, p<0.001). There were no significant differences between groups in the size of labral tear, presence of a glenoid bone defect, or Hill-Sachs lesion. After controlling for age, BMI, sex, glenoid bone defect, number of preoperative dislocations, and fixation type, only age (OR=0.896, p=0.010) and female sex (OR=5.341, p=0.008) were independent risk factors for recurrent instability and no factors were independent predictors of reoperation. Conclusion Patients undergoing AALR experienced similar rates of reoperation and recurrent instability regardless of whether a knot-tying or knotless repair was performed. The use of knotless suture anchors may improve cost-effectiveness due to decreased surgical time without diminishing postoperative outcomes.

4.
JVS Vasc Sci ; 4: 100098, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152846

RESUMO

Objective: Evaluate the mechanical and matrix effects on abdominal aortic aneurysms (AAA) during the initial aortic dilation and after prolonged exposure to beta-aminopropionitrile (BAPN) in a topical elastase AAA model. Methods: Abdominal aortae of C57/BL6 mice were exposed to topical elastase with or without BAPN in the drinking water starting 4 days before elastase exposure. For the standard AAA model, animals were harvested at 2 weeks after active elastase (STD2) or heat-inactivated elastase (SHAM2). For the enhanced elastase model, BAPN treatment continued for either 4 days (ENH2b) or until harvest (ENH2) at 2 weeks; BAPN was continued until harvest at 8 weeks in one group (ENH8). Each group underwent assessment of aortic diameter, mechanical testing (tangent modulus and ultimate tensile strength [UTS]), and quantification of insoluble elastin and bulk collagen in both the elastase exposed aorta as well as the descending thoracic aorta. Results: BAPN treatment did not increase aortic dilation compared with the standard model after 2 weeks (ENH2, 1.65 ± 0.23 mm; ENH2b, 1.49 ± 0.39 mm; STD2, 1.67 ± 0.29 mm; and SHAM2, 0.73 ± 0.10 mm), but did result in increased dilation after 8 weeks (4.3 ± 2.0 mm; P = .005). After 2 weeks, compared with the standard model, continuous therapy with BAPN did not have an effect on UTS (24.84 ± 7.62 N/cm2; 18.05 ± 4.95 N/cm2), tangent modulus (32.60 ± 9.83 N/cm2; 26.13 ± 9.10 N/cm2), elastin (7.41 ± 2.43%; 7.37 ± 4.00%), or collagen (4.25 ± 0.79%; 5.86 ± 1.19%) content. The brief treatment, EHN2b, resulted in increased aortic collagen content compared with STD2 (7.55 ± 2.48%; P = .006) and an increase in UTS compared with ENH2 (35.18 ± 18.60 N/cm2; P = .03). The ENH8 group had the lowest tangent modulus (3.71 ± 3.10 N/cm2; P = .005) compared with all aortas harvested at 2 weeks and a lower UTS (2.18 ± 2.18 N/cm2) compared with both the STD2 (24.84 ± 7.62 N/cm2; P = .008) and ENH2b (35.18 ± 18.60 N/cm2; P = .001) groups. No differences in the mechanical properties or matrix protein concentrations were associated with abdominal elastase exposure or BAPN treatment for the thoracic aorta. The tangent modulus was higher in the STD2 group (32.60 ± 9.83 N/cm2; P = .0456) vs the SHAM2 group (17.99 ± 5.76 N/cm2), and the UTS was lower in the ENH2 group (18.05 ± 4.95 N/cm2; P = .0292) compared with the ENH2b group (35.18 ± 18.60 N/cm2). The ENH8 group had the lowest tangent modulus (3.71 ± 3.10 N/cm2; P = .005) compared with all aortas harvested at 2 weeks and a lower UTS (2.18 ± 2.18 N/cm2) compared with both the STD2 (24.84 ± 7.62 N/cm2; P = .008) and ENH2b (35.18 ± 18.60 N/cm2; P = .001) groups. Abdominal aortic elastin in the STD2 group (7.41 ± 2.43%; P = .035) was lower compared with the SHAM2 group (15.29 ± 7.66%). Aortic collagen was lower in the STD2 group (4.25 ± 0.79%; P = .007) compared with the SHAM2 group (12.44 ± 6.02%) and higher for the ENH2b (7.55 ± 2.48%; P = .006) compared with the STD2 group. Conclusions: Enhancing an elastase AAA model with BAPN does not affect the initial (2-week) dilation phase substantially, either mechanically or by altering the matrix content. Late mechanical and matrix effects of prolonged BAPN treatment are limited to the elastase-exposed segment of the aorta. Clinical Relevance: This paper explores the use of short- and long-term exposure to beta-aminopropionitrile to create an enhanced topical elastase abdominal aortic aneurysm model in mice. Readouts of aneurysm severity included loss of mechanical stability and vascular extracellular matrix composition reminiscent of what is seen in the course of human disease. Additionally, we show that the thoracic aorta, unlike the findings below the renal arteries, is not damaged in our animal model.

5.
JSES Int ; 6(6): 984-988, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36353422

RESUMO

Background: Rotator cuff repairs (RCRs) are one of the most commonly performed shoulder surgeries in the United States. Psychological health has been shown to influence postoperative outcomes in orthopedic procedures. The purpose of this study is to evaluate the relationship between depression and anxiety (DA) and psychotropic medication and postoperative outcomes following RCR. Methods: A single institution retrospective observational cohort study of 816 patients undergoing arthroscopic RCR from January 2014 to October 2020 was conducted. Univariate statistics were used to assess differences in demographics, operative characteristics, and postoperative outcomes; multivariate analysis was used to evaluate risk factors for postoperative complications. Results: Patients with DA were more likely to have a higher first (3.60 vs. 3.00, P = .004) and last (1.23 vs. 0.96, P = .042) postoperative pain scores, lower first (18.67 vs. 21.85, P = .008) and last (61.87 vs. 64.71, P = .014) Upper Extremity Functional Score (UEFS), more likely to experience an emergency department visit postoperatively (9.1 vs. 5.0%, P = .028), have a symptomatic recurrent tear (8.2 vs. 3.3%, P = .003), and persistent pain (4.3 vs. 1.2%, P = .011). After controlling for age, sex, body mass index, American Society of Anesthesiologists score, diabetes, smoking, coronary artery disease, asthma, hypertension, psychotropic medication and DA, having DA at the time of surgery was independently predictive of any complication (odds ratio, 2.033; P = .028) and persistent pain (odds ratio, 8.232; P ≤ .001). Patients with and without DA showed significant improvement in postoperative pain and UEFS from the first to the last measurement (P < .001). Conclusion: DA is not a deterrent for RCR but targeted interventions may be needed to decrease the occurrence of complications.

6.
Front Immunol ; 13: 893177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874727

RESUMO

Purpose: Clinical successes using current T-cell based immunotherapies have been limited in soft tissue sarcomas (STS), while pre-clinical studies have shown evidence of natural killer (NK) cell activity. Since tumor immune infiltration, especially tumor-infiltrating lymphocytes, is associated with improved survival in most solid tumors, we sought to evaluate the gene expression profile of tumor and blood NK and T cells, as well as tumor cells, with the goal of identifying potential novel immune targets in STS. Experimental Design: Using fluorescence-activated cell sorting, we isolated blood and tumor-infiltrating CD3-CD56+ NK and CD3+ T cells and CD45- viable tumor cells from STS patients undergoing surgery. We then evaluated differential gene expression (DGE) of these purified populations with RNA sequencing analysis. To evaluate survival differences and validate primary DGE results, we also queried The Cancer Genome Atlas (TCGA) database to compare outcomes stratified by bulk gene expression. Results: Sorted intra-tumoral CD3+ T cells showed significant upregulation of established activating (CD137) and inhibitory genes (TIM-3) compared to circulating T cells. In contrast, intra-tumoral NK cells did not exhibit upregulation of canonical cytotoxic genes (IFNG, GZMB), but rather significant DGE in mitogen signaling (DUSP4) and metabolic function (SMPD3, SLC7A5). Tumors with higher NK and T cell infiltration exhibited significantly increased expression of the pro-inflammatory receptor TLR4 in sorted CD45- tumor cells. TCGA analysis revealed that tumors with high TLR4 expression (P = 0.03) and low expression of STMN1 involved in microtubule polymerization (P < 0.001) were associated with significantly improved survival. Conclusions: Unlike T cells, which demonstrate significant DGE consistent with upregulation of both activating and inhibiting receptors in tumor-infiltrating subsets, NK cells appear to have more stable gene expression between blood and tumor subsets, with alterations restricted primarily to metabolic pathways. Increased immune cell infiltration and improved survival were positively correlated with TLR4 expression and inversely correlated with STMN1 expression within tumors, suggesting possible novel therapeutic targets for immunotherapy in STS.


Assuntos
Células Matadoras Naturais , Linfócitos do Interstício Tumoral , Sarcoma , Neoplasias de Tecidos Moles , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Receptor 4 Toll-Like/metabolismo , Transcriptoma
7.
J Periodontol ; 93(6): 847-856, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35289400

RESUMO

BACKGROUND: There is limited information on the need for bone augmentation in the context of delayed implant placement whether alveolar ridge preservation (ARP) is previously performed or not. The primary aim of this retrospective cohort study was to evaluate the efficacy of ARP therapy after tooth extraction compared with unassisted socket healing (USH) in reducing the need for ancillary bone augmentation before or at the time of implant placement. METHODS: Adult subjects that underwent non-molar single tooth extraction with or without simultaneous ARP therapy were included in this study. Cone beam computed tomography scans obtained before tooth extraction and after a variable healing period were used to record the baseline facial bone thickness and to virtually plan implant placement according to a standard method. A logistic regression model was used to evaluate the effect of facial alveolar bone thickness upon tooth extraction and baseline therapy (USH or ARP) on the need for additional bone augmentation, adjusting for several covariates (i.e., age, sex, baseline KMW, and tooth type). RESULTS: One hundred and forty subjects that were equally distributed between both baseline therapy groups constituted the study population. Implant placement was deemed virtually feasible in all study sites. Simultaneous bone augmentation was considered necessary in 60% and 11.4% of the sites in the USH and ARP group, respectively. Most of these sites (64.2% in the USH group and 87.5% in the ARP group) exhibited a thin facial bone phenotype (<1 mm) at baseline. Logistic regression revealed that the odds of not needing ancillary bone augmentation were 17.8 times higher in sites that received ARP therapy. Furthermore, the need for additional bone augmentation was reduced 7.7 times for every 1 mm increase in facial bone thickness, regardless of baseline therapy. CONCLUSIONS: Based on a digital analysis, ARP therapy, compared with USH, and thick facial alveolar bone largely reduce the need for ancillary bone augmentation at the time of implant placement in non-molar sites.


Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Adulto , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/cirurgia , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/cirurgia , Aumento do Rebordo Alveolar/métodos , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Estudos Retrospectivos , Extração Dentária , Alvéolo Dental/diagnóstico por imagem , Alvéolo Dental/cirurgia
8.
Infect Control Hosp Epidemiol ; 43(7): 876-885, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34016200

RESUMO

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus. DESIGN: The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance. METHODS: MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method. RESULTS: Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3. CONCLUSIONS: MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.


Assuntos
COVID-19 , Viroses , COVID-19/prevenção & controle , Descontaminação/métodos , Reutilização de Equipamento , Humanos , Máscaras , Azul de Metileno/farmacologia , Respiradores N95 , Equipamento de Proteção Individual , SARS-CoV-2
10.
Oral Oncol ; 113: 105094, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33242736

RESUMO

BACKGROUND: Although the concept of maintaining a period of 'nil by mouth' following head and neck reconstruction is commonly held ideas on delaying function have changed dramatically since the introduction of peri-operative care recovery programmes. This study sought to evaluate the outcomes of early feeding on patients undergoing free flap reconstruction of oral defects with particular emphasis on post-operative complications and length of stay. METHODS: Data was gathered prospectively on two cohorts of patients treated in a tertiary referral centre comparing those undergoing a five-day post-operative period of 'nil by mouth' with a second group in which the aim was to start fluids and soft diet on the day following surgery. Complications and length of stay were evaluated. RESULTS: Both early and late feeding groups comprised of 200 patients. No significant differences were observed in terms of age, gender, smoking and alcohol use or tumour T and N stages between the two groups. 8% of patients had complications at the recipient site but no difference was observed in the rates of flap dehiscence or fistula formation between the two groups. Early feeding was associated with a statistically reduced length of hospital stay (mean 11.6 days vs 20.6 days, p < 0.01). CONCLUSIONS: Early oral feeding following head and neck free flap reconstruction is not associated with an increase incidence of peri-operative complications but reduces hospital stay. The latter may have far-reaching implications for patients' physical and psychological well-being in addition to health care resources.


Assuntos
Nutrição Enteral/métodos , Neoplasias de Cabeça e Pescoço/cirurgia , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
11.
Ann Oncol ; 32(3): 395-403, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33276076

RESUMO

BACKGROUND: Quavonlimab (MK-1308), a novel anti-CTLA-4 antibody, in combination with pembrolizumab was investigated in a phase I study. PATIENTS AND METHODS: Dose-escalation (DE) phase: patients with advanced/metastatic solid tumors received an initial flat dose of quavonlimab as monotherapy [25 mg (cohort 1), 75 mg (cohort 2), or 200 mg (cohort 3)] followed by four treatments of the same quavonlimab dose plus pembrolizumab every 3 weeks (Q3W). Dose-confirmation phase (DC): patients with stage IIIB/IV non-small-cell lung cancer (NSCLC) received first-line quavonlimab [25 mg Q3W (arm A), 25 mg Q6W (arm B), 75 mg Q6W (arm C), or 75 mg Q3W (arm E)] plus pembrolizumab. Primary objectives were safety and tolerability and establishment of the recommended phase II dose (RP2D) of quavonlimab when used with pembrolizumab. Objective response rate (ORR) was a secondary endpoint. Efficacy based on PD-L1 expression, tumor mutational burden (TMB), and changes in circulating CD4+/CD8+ cells were exploratory endpoints. RESULTS: Thirty-nine patients were enrolled in DE [n = 14 (cohort 1); n = 17 (cohort 2); n = 8 (cohort 3)] and 134 in DC [n = 40 (arm A); n = 40 (arm B); n = 40 (arm C); n = 14 (arm E)]. Maximum-tolerated dose was not reached. Grade 3-5 treatment-related adverse events (AEs; graded according to NCI CTCAE v4.03) occurred in 0%, 23.5%, and 75.0% of patients in DE cohorts 1, 2, and 3, respectively, and 35.0%, 30.0%, 35.0%, and 57.1% of patients in DC arms A, B, C, and E, respectively. Efficacy was observed at all dose levels/schedules in patients with NSCLC. ORRs were 40.0% [95% confidence interval (CI), 24.9-56.7; arm A], 37.5% (95% CI, 22.7-54.2; arm B), 27.5% (95% CI, 14.6-43.9; arm C), and 35.7% (95% CI, 12.8-64.9; arm E). PD-L1 expression and total number of circulating CD4+ cells correlated with ORR. CONCLUSIONS: Quavonlimab 25 mg Q6W plus pembrolizumab demonstrated similar efficacy and a better safety profile among all quavonlimab doses/schedules evaluated; this regimen was the chosen RP2D.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico
12.
J Orthop ; 22: 372-376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952329

RESUMO

OBJECTIVE: The addition of open subpectoral biceps tenodesis to arthroscopic shoulder surgery with interscalene block has been anecdotally observed to result in increased postoperative pain. This study aims to evaluate the impact of tenodesis on early postoperative pain and recovery. METHODS: A retrospective review of patients undergoing arthroscopic shoulder surgery with general anesthesia and interscalene block was conducted. RESULTS: Patients undergoing tenodesis experienced longer OR time, pain numeric rating scale (NRS), and consumed more morphine milligram equivalents (MME) in PACU. After controlling for confounding factors, tenodesis was significantly associated with increased opioid MME consumption in the PACU (ß = 1.045, p = .028) and last PACU pain NRS (ß = 0.541, p = .009). CONCLUSION: Overall, pain scores and narcotic consumption were low after surgery, making these differences potentially clinically insignificant. Further study is required to evaluate whether these trends are consistent among this population.

13.
J Biomech Eng ; 142(11)2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32700727

RESUMO

In this paper, we bridged faculty research expertise with concept-based learning pedagogy to design and implement a unique laboratory experience for biomedical engineering undergraduate students enrolled in the biomechanics of tissues course at the University of Calgary. This laboratory aimed to increase student engagement, facilitate deeper understanding of course content, and provide an opportunity for accelerated undergraduate research through "hands-on," "minds-on," and "science-up" learning components, respectively. The laboratory exercise involves testing aortic tissues using a novel miniaturized planar biaxial machine. This type of machine is normally reserved for use in the context of research. The relevance of the proposed laboratory as a teaching tool was assessed using student feedback. Results indicate an overall valuable and positive learning experience for students.


Assuntos
Engenharia Biomédica , Laboratórios , Estudantes , Paladar
14.
Ultrason Sonochem ; 48: 218-230, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30080545

RESUMO

Acoustic streaming phenomena of ultrasound propagation through liquid media was investigated experimentally employing particle image velocimetry (PIV). Parameters associated with the ultrasonic processor of ultrasonic amplitude (i.e., acoustic power) and transducer tip diameter (i.e., surface area), as well as, fluid rheology (i.e., water, glycerol solution and CMC solution), were studied for their effects on overall flow behaviour and fluid velocity. PIV yielded velocity gradient maps, demonstrating the acoustic streaming phenomena of ultrasound and its associated flow behaviour as a function of ultrasonic amplitude and fluid rheology, whereby increasing amplitude allowed for greater penetration of the acoustic-beam through the bulk of the fluid, and increasing fluid rheology yielded the converse effect. Moreover, upon impingement of the acoustic-beam with the base of vessel, vortex formation occurred, yielding a recirculation pattern. The maximum observed fluid velocities for water, glycerol solution and CMC solution were 0.329 m s-1, 0.423 m s-1, and 0.304 m s-1, respectively (large diameter sonotrode tip for an ultrasonic amplitude of 80%). Furthermore, shear rates were attained (maximum values of 24.25 s-1), and Reynolds numbers were determined in order to assess the degree of turbulence as a function of investigated parameters.

15.
Bioorg Med Chem Lett ; 28(2): 207-213, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29191556

RESUMO

A 900 compound nitroimidazole-based library derived from our pretomanid backup program with TB Alliance was screened for utility against human African trypanosomiasis (HAT) by the Drugs for Neglected Diseases initiative. Potent hits included 2-nitro-6,7-dihydro-5H-imidazo[2,1-b][1,3]thiazine 8-oxides, which surprisingly displayed good metabolic stability and excellent cell permeability. Following comprehensive mouse pharmacokinetic assessments on four hits and determination of the most active chiral form, a thiazine oxide counterpart of pretomanid (24) was identified as the best lead. With once daily oral dosing, this compound delivered complete cures in an acute infection mouse model of HAT and increased survival times in a stage 2 model, implying the need for more prolonged CNS exposure. In preliminary SAR findings, antitrypanosomal activity was reduced by removal of the benzylic methylene but enhanced through a phenylpyridine-based side chain, providing important direction for future studies.


Assuntos
Nitroimidazóis/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Tripanossomíase Africana/tratamento farmacológico , Administração Oral , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Humanos , Camundongos , Estrutura Molecular , Nitroimidazóis/administração & dosagem , Nitroimidazóis/química , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
16.
Mar Pollut Bull ; 107(2): 459-71, 2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27210565

RESUMO

Some barrier-island dunes damaged or destroyed by Hurricane Sandy's storm surges in October 2012 have been reconstructed using sediments dredged from back bays. These sand-, clay-, and iron sulfide-rich sediments were used to make berm-like cores for the reconstructed dunes, which were then covered by beach sand. In November 2013, we sampled and analyzed partially weathered materials collected from the cores of reconstructed dunes. There are generally low levels of metal toxicants in the reconstructed dune materials. However oxidation of reactive iron sulfides by percolating rainwater produces acid-sulfate pore waters, which evaporate during dry periods to produce efflorescent gypsum and sodium jarosite salts. The results suggest use of sulfidic sediments in dune reconstruction has both drawbacks (e.g., potential to generate acid runoff from dune cores following rainfall, enhanced corrosion of steel bulwarks) and possible benefits (e.g., efflorescent salts may enhance structural integrity).


Assuntos
Tempestades Ciclônicas , Monitoramento Ambiental , Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/química , Sulfetos/análise , Poluentes Químicos da Água/análise , Baías/química , Ilhas , Metais/análise , New Jersey , New York
17.
Pharmaceuticals (Basel) ; 9(2)2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27104545

RESUMO

A series of 15 alkanediamide-linked bisbenzamidines and related analogs was synthesized and tested in vitro against two Trypanosoma brucei (T.b.) subspecies: T.b. brucei and T.b. rhodesiense, Trypanosoma cruzi, Leishmania donovani and two Plasmodium falciparum subspecies: a chloroquine-sensitive strain (NF54) and a chloroquine-resistant strain (K1). The in vitro cytotoxicity was determined against rat myoblast cells (L6). Seven compounds (5, 6, 10, 11, 12, 14, 15) showed high potency against both strains of T. brucei and P. falciparum with the inhibitory concentrations for 50% (IC50) in the nanomolar range (IC50 = 1-96 nM). None of the tested derivatives was significantly active against T. cruzi or L. donovani. Three of the more potent compounds (5, 6, 11) were evaluated in vivo in mice infected with the drug-sensitive (Lab 110 EATRO and KETRI 2002) or drug-resistant (KETRI 2538 and KETRI 1992) clinical isolates of T. brucei. Compounds 5 and 6 were highly effective in curing mice infected with the drug-sensitive strains, including a drug-resistant strain KETRI 2538, but were ineffective against KETRI 1992. Thermal melting of DNA and molecular modeling studies indicate AT-rich DNA sequences as possible binding sites for these compounds. Several of the tested compounds are suitable leads for the development of improved antiparasitic agents.

19.
Head Neck ; 38(5): 670-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25524696

RESUMO

BACKGROUND: Acoustic evaluation of speech is the least explored method of speech evaluation in patients with oral cavity and oropharyngeal cancer. The purpose of this study was to explore acoustic parameters of speech and their correlation with questionnaire evaluation and perceptual evaluation in patients with oral cavity and oropharyngeal cancer. METHODS: One hundred seventeen subjects (65 consecutive patients with oral cavity and oropharyngeal cancer and 52 controls) participated in this study. Formant frequencies (by Linear Predictive Coding), Speech Handicap Index, and London Speech Evaluation scale were used for acoustic evaluation, questionnaire evaluation, and perceptual evaluation, respectively. RESULTS: Men showed significant elevation in second formant (F2) values for patients with oral cavity cancer and those who underwent surgery alone. Female patients with early T classification cancers and those who underwent surgery and chemoradiation showed significant reduction in the mean F2 values. Importantly, however, acoustic evaluation parameters did not correlate with either perceptual evaluation or questionnaire evaluation parameters, although there was moderate correlation between questionnaire evaluation and perceptual evaluation speech parameters. CONCLUSION: Acoustic evaluation modalities have no clear role in the management of patients with oral cavity and oropharyngeal cancer.


Assuntos
Neoplasias Bucais/cirurgia , Neoplasias Orofaríngeas/cirurgia , Acústica da Fala , Distúrbios da Fala/diagnóstico , Medida da Produção da Fala/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/fisiopatologia , Neoplasias Orofaríngeas/fisiopatologia , Distúrbios da Fala/etiologia , Inteligibilidade da Fala , Inquéritos e Questionários
20.
Bioorg Med Chem ; 23(5): 996-1010, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25661449

RESUMO

Trypanothione reductase (TR) is an enzyme critical to the maintenance of the thiol redox balance in trypanosomatids, including the genera Trypanosoma and Leishmania that are parasites responsible for several serious diseases. Analogs of clomipramine were prepared since clomipramine is reported to inhibit TR and cure mice infected with trypanosomes, however its psychotropic activity precludes its use as an anti-trypanosomal therapeutic. The clomipramine analogs contained a tricyclic dibenzosuberyl moiety. Additionally a series of polyamines with N-dibenzosuberyl substituents were prepared. All compounds studied were competitive inhibitors of TR and showed trypanocidal activities against Trypanosoma brucei in vitro. The analogs of clomipramine were poor inhibitors of TR, whereas the polyamine derivatives were effective TR inhibitors with the most potent compound, N(4),N(8)-bis(dibenzosuberyl)spermine (7), having a Ki value of 0.26µM. However, compound (7) did not prolong the lives of mice infected with trypanosomes. Analysis of docking studies indicated: the tricyclic groups of inhibitors bind at four distinct hydrophobic regions in the active site of TR; the importance of the chlorine substituent of clomipramine in binding to TR; and binding of the dibenzosuberyl groups of (7) occur at separate and distinct hydrophobic regions within the active site of TR.


Assuntos
Clomipramina/análogos & derivados , Inibidores Enzimáticos/farmacologia , NADH NADPH Oxirredutases/antagonistas & inibidores , Poliaminas/farmacologia , Tripanossomicidas/farmacologia , Animais , Clomipramina/química , Inibidores Enzimáticos/química , Camundongos , Simulação de Acoplamento Molecular , Poliaminas/química , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma brucei brucei/enzimologia
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