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1.
Injury ; 55(8): 111686, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38976927

RESUMO

INTRODUCTION: Approximately 20 % of femoral fragility fracture patients take anticoagulants, typically warfarin or Direct Oral AntiCoagulant (DOAC). These can impact timing of surgery affecting patient survival. Due to several possible approaches and numerous factors to consider in the preoperative workup of anticoagulated patients, potential for variations in clinical practice exist. Some hospitals employ dedicated anticoagulation management protocols to address this issue, and to improve time to surgery. This study aimed to determine the proportion of hospitals with such protocols, compare protocol guidance between hospitals, and evaluate the effectiveness of protocols in facilitating prompt surgery. METHODS: Data was prospectively collected through a collaborative, multicentre approach involving hospitals across the UK. Femoral fragility fracture patients aged ≥60 years and admitted to hospital between 1st May to 31st July 2023 were included. Information from dedicated anticoagulation management protocols were collated on several domains relating to perioperative care including administration of reversal agents and instructions on timing of surgery as well as others. Logistic regression was used to evaluate effects of dedicated protocols on time to surgery. RESULTS: Dedicated protocols for management of patients taking warfarin and DOACs were present at 41 (52.6 %) and 43 (55.1 %) hospitals respectively. For patients taking warfarin, 39/41 (95.1 %) protocols specified the dose of vitamin k and the most common was 5 milligrams intravenously (n=21). INR threshold values for proceeding to surgery varied between protocols; 1.5 (n=28), 1.8 (n=6), and 2 (n=6). For patients taking DOACs, 35/43 (81.4 %) and 8/43 (18.6 %) protocols advised timing of surgery based on renal function and absolute time from last dose respectively. Analysis of 10,197 patients from 78 hospitals showed fewer patients taking DOACs received surgery within 36 h of admission at hospitals with a dedicated protocol compared to those without (adjusted OR 0.73, 95% CI 0.54-0.99, p=0.040), while there were no differences among patients taking warfarin (adjusted OR 1.64, 95% CI 0.75-3.57, p=0.219). CONCLUSIONS: Around half of hospitals employed a dedicated anticoagulation management protocol for femoral fragility fracture patients, and substantial variation was observed in guidance between protocols. Dedicated protocols currently being used at hospitals were ineffective at improving the defined targets for time to surgery.

2.
Osteoarthritis Cartilage ; 32(7): 912-921, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38642879

RESUMO

OBJECTIVE: Exercise remains a hallmark treatment for post-traumatic osteoarthritis (PTOA) and may maintain joint homeostasis in part by clearing inflammatory cytokines, cells, and particles. It remains largely unknown whether exercise-induced joint clearance can provide therapeutic relief of PTOA. In this study, we hypothesized that exercise could slow the progression of preclinical PTOA in part by enhancing knee joint clearance. DESIGN: Surgical medial meniscal transection was used to induce PTOA in 3-month-old male Lewis rats. A sham surgery was used as a control. Mild treadmill walking was introduced 3 weeks post-surgery and maintained to 6 weeks post-surgery. Gait and isometric muscle torque were measured at the study endpoint. Near-infrared imaging tracked how exercise altered lymphatic and venous knee joint clearance during discrete time points of PTOA progression. RESULTS: Exercise mitigated joint degradation associated with PTOA by preserving glycosaminoglycan content and reducing osteophyte volume (effect size (95% Confidence Interval (CI)); 1.74 (0.71-2.26)). PTOA increased hind step widths (0.57 (0.18-0.95) cm), but exercise corrected this gait dysfunction (0.54 (0.16-0.93) cm), potentially indicating pain relief. Venous, but not lymphatic, clearance was quicker 1-, 3-, and 6-weeks post-surgery compared to baseline. The mild treadmill walking protocol expedited lymphatic clearance rate in moderate PTOA (3.39 (0.20-6.59) hrs), suggesting exercise may play a critical role in restoring joint homeostasis. CONCLUSIONS: We conclude that mild exercise has the potential to slow disease progression in part by expediting joint clearance in moderate PTOA.


Assuntos
Instabilidade Articular , Osteoartrite do Joelho , Condicionamento Físico Animal , Ratos Endogâmicos Lew , Animais , Masculino , Ratos , Condicionamento Físico Animal/fisiologia , Instabilidade Articular/fisiopatologia , Osteoartrite do Joelho/fisiopatologia , Modelos Animais de Doenças , Marcha/fisiologia , Articulação do Joelho/fisiopatologia , Glicosaminoglicanos/metabolismo , Osteoartrite/fisiopatologia , Osteoartrite/metabolismo , Osteófito , Progressão da Doença
3.
ACS Biomater Sci Eng ; 10(4): 2177-2187, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38466617

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) accounts for about 90% of all pancreatic cancer cases. Five-year survival rates have remained below 12% since the 1970s, in part due to the difficulty in detection prior to metastasis (migration and invasion into neighboring organs and glands). Mechanical memory is a concept that has emerged over the past decade that may provide a path toward understanding how invading PDAC cells "remember" the mechanical properties of their diseased ("stiff", elastic modulus, E ≈ 10 kPa) microenvironment even while invading a healthy ("soft", E ≈ 1 kPa) microenvironment. Here, we investigated the role of mechanical priming by culturing a dilute suspension of PDAC (FG) cells within a 3D, rheologically tunable microgel platform from hydrogels with tunable mechanical properties. We conducted a suite of acute (short-term) priming studies where we cultured PDAC cells in either a soft (E ≈ 1 kPa) or stiff (E ≈ 10 kPa) environment for 6 h, then removed and placed them into a new soft or stiff 3D environment for another 18 h. Following these steps, we conducted RNA-seq analyses to quantify gene expression. Initial priming in the 3D culture showed persistent gene expression for the duration of the study, regardless of the subsequent environments (stiff or soft). Stiff 3D culture was associated with the downregulation of tumor suppressors (LATS1, BCAR3, CDKN2C), as well as the upregulation of cancer-associated genes (RAC3). Immunofluorescence staining (BCAR3, RAC3) further supported the persistence of this cellular response, with BCAR3 upregulated in soft culture and RAC3 upregulated in stiff-primed culture. Stiff-primed genes were stratified against patient data found in The Cancer Genome Atlas (TCGA). Upregulated genes in stiff-primed 3D culture were associated with decreased survival in patient data, suggesting a link between patient survival and mechanical priming.


Assuntos
Carcinoma Ductal Pancreático , Microgéis , Neoplasias Pancreáticas , Humanos , Linhagem Celular Tumoral , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Hidrogéis , Microambiente Tumoral/genética
4.
EMBO Mol Med ; 16(4): 823-853, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480932

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, characterized by extensive intratumoral heterogeneity, high metastasis, and chemoresistance, leading to poor clinical outcomes. Despite progress, the mechanistic basis of these aggressive behaviors remains poorly understood. Using single-cell and spatial transcriptome analysis, here we discovered basal epithelial subpopulations located within the stroma that exhibit chemoresistance characteristics. The subpopulations are defined by distinct signature genes that show a frequent gain in copy number and exhibit an activated epithelial-to-mesenchymal transition program. A subset of these genes can accurately predict chemotherapy response and are associated with poor prognosis. Interestingly, among these genes, elevated ITGB1 participates in enhancing intercellular signaling while ACTN1 confers a survival advantage to foster chemoresistance. Furthermore, by subjecting the transcriptional signatures to drug repurposing analysis, we find that chemoresistant tumors may benefit from distinct inhibitors in treatment-naive versus post-NAC patients. These findings shed light on the mechanistic basis of chemoresistance while providing the best-in-class biomarker to predict chemotherapy response and alternate therapeutic avenues for improved management of TNBC patients resistant to chemotherapy.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Transcriptoma , Perfilação da Expressão Gênica , Transdução de Sinais , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral
5.
Res Sq ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38496632

RESUMO

Radiotherapy (RT) and anti-PD-L1 synergize to enhance local and distant (abscopal) tumor control. However, clinical results in humans have been variable. With the goal of improving clinical outcomes, we investigated the underlying synergistic mechanism focusing on a CD8+ PD-1+ Tcf-1+ stem-like T cell subset in the tumor-draining lymph node (TdLN). Using murine melanoma models, we found that RT + anti-PD-L1 induces a novel differentiation program in the TdLN stem-like population which leads to their expansion and differentiation into effector cells within the tumor. Our data indicate that optimal synergy between RT + anti-PD-L1 is dependent on the TdLN stem-like T cell population as either blockade of TdLN egress or specific stem-like T cell depletion reduced tumor control. Together, these data demonstrate a multistep stimulation of stem-like T cells following combination therapy which is initiated in the TdLN and completed in the tumor.

6.
Transl Vis Sci Technol ; 13(1): 27, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38289612

RESUMO

Purpose: Vision-related disorders, such as refractive errors and binocular vision issues, can cause headaches. The current study evaluates the impact of Neurolens (NL) on individuals with headaches, assessed using the Headache Impact Test (HIT) questionnaire. Methods: Subjects (18-60 years) with good stereoacuity and a HIT score of ≥56 points were enrolled. Each subject wore both control lens and NL for 30 ± 10 days each. The primary outcome of the study was to assess the difference in the HIT score between the two treatments. Results: Of the subjects randomized, 88% (170/195) completed the study. Overall, subjects reported a greater improvement in HIT score improvement with NL compared with control (mean difference, -1.53 points; 95% confidence interval, -2.8 to -0.26; P = 0.01). In the subgroup with reduced NPC, subjects reported a larger improvement in HIT score improvement with NL but was not statistically significant (mean difference, -1.89 points; 95% confidence interval, -4.27 to -0.47; P = 0.11). Conclusions: NL produced a statistically significant decrease in the impact of headaches on individuals' quality of life compared with placebo. Although the overall magnitude of the decrease was not clinically significant, a clinically meaningful improvement with NL cannot be ruled out with high certainty in the current study. Translational Relevance: Headache is one of the most experienced symptoms by individuals worldwide with vision-related disorders being a primary reason. It is, therefore, critical to screen these disorders before providing a pharmacological intervention, which may have side effects. NL provides an objective way to diagnose and treat digital eyestrain-related headaches.


Assuntos
Qualidade de Vida , Erros de Refração , Humanos , Método Duplo-Cego , Cefaleia/diagnóstico , Cefaleia/terapia , Estudos Cross-Over
7.
Sci Rep ; 13(1): 21241, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040740

RESUMO

Lymphedema is a condition in which lymph transport is compromised. The factors that govern the timing of lymphatic contractions are largely unknown; however, these factors likely play a central role in lymphatic health. Computational models have proven useful in quantifying changes in lymph transport; nevertheless, there is still much unknown regarding the regulation of contractions. The purpose of this paper is to utilize computational modeling to examine the role of pacemaking activity in lymph transport. A 1D fluid-solid modeling framework was utilized to describe the interaction between the contracting vessel and the lymph flow. The distribution of contractions along a three-lymphangion chain in time and space was determined by specifying the pacemaking sites and parameters obtained from experimentation. The model effectively replicates the contractility patterns in experiments. Quantitatively, the flow rates were measured at 5.44 and 2.29 [Formula: see text], and the EF values were 78% and less than 33% in the WT and KO models, respectively, which are consistent with the literature. Applying pacemaking parameters in this modeling framework effectively captures lymphatic contractile wave propagations and their relation to lymph transport. It can serve as a motivation for conducting novel studies to evaluate lymphatic pumping function during the development of lymphedema.


Assuntos
Vasos Linfáticos , Linfedema , Humanos , Linfa/fisiologia , Vasos Linfáticos/fisiologia , Contração Muscular/fisiologia , Simulação por Computador , Sistema Linfático/fisiologia
8.
Front Sports Act Living ; 5: 1253007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022788

RESUMO

Early sport specialization is a popular and contentious topic in the scientific literature and popular media. The lure of extrinsic rewards has led to increasing rates of specialization among young athletes, while expert recommendations promote multisport participation. The purpose of this study was to describe and analyze developmental activities of a group of elite junior hockey players in Canada. Within this context, elements of specialization were investigated in accordance with existing theoretical frameworks and long-term athlete development models to enhance the literature. Fifteen participants from the Ontario Hockey League completed quantitative retrospective interviews, detailing past sport and recreational activities. Thirty-one developmental milestones were assessed. Accumulated hours of activity were categorized in accordance with Côté's (1999) Developmental Model of Sports Participation, along with the number and types of sports in which they participated during childhood. Jayanthi et al.'s (2015) continuum was utilized to determine the age at which the athletes became moderately and highly specialized. Accrued hours of deliberate practice reported by participants increased from ages 6 to 16 years, as did competition in organized hockey games. Reported hours of deliberate play peaked at 9 years of age and decreased thereafter. Participants played a combined 16 sports other than hockey, ranging from an average of 2.0 at age 6, to a maximum average of 5.6 at 12 years old, and decreasing each year to 2.3 by age 15. The greatest number of hours in other sports was accumulated at 12 years of age. Using a three-point scale, participants considered themselves "highly specialized" at 14 years old; however, other quantitative indicators suggested this may have occurred at 12 years of age. Relative to previous research on early sport specialization, participants in this study spent more time practicing hockey, while ceasing hockey-specific play and other sports at younger ages. Despite a diverse sport history, hockey competition was initiated earlier than recommended, showing high levels of sport commitment as young as 9 years old. The early specialization path remains a popular trajectory among coaches, parents, and athletes in Canadian ice hockey.

9.
Pro Inst Mech Eng Part J J Eng Tribol ; 237(5): 1264-1271, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-38024847

RESUMO

Silicone elastomer medical implants are ubiquitous in medicine, particularly for breast augmentation. However, when these devices are placed within the body, disruption of the natural biological interfaces occurs, which significantly changes the native energy-dissipation mechanisms of living systems. These new interfaces can introduce non-physiological contact pressures and tribological conditions that provoke inflammation and soft tissue damage. Despite their significance, the biotribological properties of implant-tissue and implant-extracellular matrix (ECM) interfaces remain poorly understood. Here, we developed an in vitro model of soft tissue damage using a custom-built in situ biotribometer mounted onto a confocal microscope. Sections of commercially-available silicone breast implants with distinct and clinically relevant surface roughness (Ra = 0.2 ± 0.03 µm, 2.7 ± 0.6 µm, and 32 ± 7.0 µm) were mounted to spherically-capped hydrogel probes and slid against collagen-coated hydrogel surfaces as well as healthy breast epithelial (MCF10A) cell monolayers to model implant-ECM and implant-tissue interfaces. In contrast to the "smooth" silicone implants (Ra < 10 µm), we demonstrate that the "microtextured" silicone implant (10 < Ra < 50 µm) induced higher frictional shear stress (τ > 100 Pa), which led to greater collagen removal and cell rupture/delamination. Our studies may provide insights into post-implantation tribological interactions between silicone breast implants and soft tissues.

10.
J Pers Med ; 13(10)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888087

RESUMO

The majority of breast cancers are oestrogen receptor-positive (ER+). In ER+ cancers, oestrogen acts as a disease driver, so these tumours are likely to be susceptible to endocrine therapy (ET). ET works by blocking the hormone's synthesis or effect. A significant number of patients diagnosed with breast cancer will have the spread of tumour cells into regional lymph nodes either at the time of diagnosis, or as a recurrence some years later. Patients with node-positive disease have a poorer prognosis and can respond less well to ET. The nodal metastases may be genomically similar or, as is becoming more evident, may differ from the primary tumour. However, nodal metastatic disease is often not assessed, and treatment decisions are almost always based on biomarkers evaluated in the primary tumour. This review will summarise the evidence in the field on ER+, node-positive breast cancer, including diagnosis, treatment, prognosis and predictive tools.

11.
Circulation ; 148(16): 1231-1249, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37609838

RESUMO

BACKGROUND: Lymphedema is a global health problem with no effective drug treatment. Enhanced T-cell immunity and abnormal lymphatic endothelial cell (LEC) signaling are promising therapeutic targets for this condition. Sphingosine-1-phosphate (S1P) mediates a key signaling pathway required for normal LEC function, and altered S1P signaling in LECs could lead to lymphatic disease and pathogenic T-cell activation. Characterizing this biology is relevant for developing much needed therapies. METHODS: Human and mouse lymphedema was studied. Lymphedema was induced in mice by surgically ligating the tail lymphatics. Lymphedematous dermal tissue was assessed for S1P signaling. To verify the role of altered S1P signaling effects in lymphatic cells, LEC-specific S1pr1-deficient (S1pr1LECKO) mice were generated. Disease progression was quantified by tail-volumetric and -histopathologic measurements over time. LECs from mice and humans, with S1P signaling inhibition, were then cocultured with CD4 T cells, followed by an analysis of CD4 T-cell activation and pathway signaling. Last, animals were treated with a monoclonal antibody specific to P-selectin to assess its efficacy in reducing lymphedema and T-cell activation. RESULTS: Human and experimental lymphedema tissues exhibited decreased LEC S1P signaling through S1P receptor 1 (S1PR1). LEC S1pr1 loss-of-function exacerbated lymphatic vascular insufficiency, tail swelling, and increased CD4 T-cell infiltration in mouse lymphedema. LECs, isolated from S1pr1LECKO mice and cocultured with CD4 T cells, resulted in augmented lymphocyte differentiation. Inhibiting S1PR1 signaling in human dermal LECs promoted T-helper type 1 and 2 (Th1 and Th2) cell differentiation through direct cell contact with lymphocytes. Human dermal LECs with dampened S1P signaling exhibited enhanced P-selectin, an important cell adhesion molecule expressed on activated vascular cells. In vitro, P-selectin blockade reduced the activation and differentiation of Th cells cocultured with shS1PR1-treated human dermal LECs. P-selectin-directed antibody treatment improved tail swelling and reduced Th1/Th2 immune responses in mouse lymphedema. CONCLUSIONS: This study suggests that reduction of the LEC S1P signaling aggravates lymphedema by enhancing LEC adhesion and amplifying pathogenic CD4 T-cell responses. P-selectin inhibitors are suggested as a possible treatment for this pervasive condition.


Assuntos
Linfedema , Selectina-P , Humanos , Camundongos , Animais , Transdução de Sinais , Inflamação/patologia , Linfedema/patologia
12.
medRxiv ; 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37398237

RESUMO

BACKGROUND: Lymphedema is a global health problem with no effective drug treatment. Enhanced T cell immunity and abnormal lymphatic endothelial cell (LEC) signaling are promising therapeutic targets for this condition. Sphingosine-1-phosphate (S1P) mediates a key signaling pathway required for normal LEC function, and altered S1P signaling in LECs could lead to lymphatic disease and pathogenic T cell activation. Characterizing this biology is relevant for developing much-needed therapies. METHODS: Human and mouse lymphedema was studied. Lymphedema was induced in mice by surgically ligating the tail lymphatics. Lymphedematous dermal tissue was assessed for S1P signaling. To verify the role of altered S1P signaling effects in lymphatic cells, LEC-specific S1pr1 -deficient ( S1pr1 LECKO ) mice were generated. Disease progression was quantified by tail-volumetric and -histopathological measurements over time. LECs from mice and humans, with S1P signaling inhibition, were then co-cultured with CD4 T cells, followed by an analysis of CD4 T cell activation and pathway signaling. Finally, animals were treated with a monoclonal antibody specific to P-selectin to assess its efficacy in reducing lymphedema and T cell activation. RESULTS: Human and experimental lymphedema tissues exhibited decreased LEC S1P signaling through S1PR1. LEC S1pr1 loss-of-function exacerbated lymphatic vascular insufficiency, tail swelling, and increased CD4 T cell infiltration in mouse lymphedema. LECs, isolated from S1pr1 LECKO mice and co-cultured with CD4 T cells, resulted in augmented lymphocyte differentiation. Inhibiting S1PR1 signaling in human dermal LECs (HDLECs) promoted T helper type 1 and 2 (Th1 and Th2) cell differentiation through direct cell contact with lymphocytes. HDLECs with dampened S1P signaling exhibited enhanced P-selectin, an important cell adhesion molecule expressed on activated vascular cells. In vitro , P-selectin blockade reduced the activation and differentiation of Th cells co-cultured with sh S1PR1 -treated HDLECs. P-selectin-directed antibody treatment improved tail swelling and reduced Th1/Th2 immune responses in mouse lymphedema. CONCLUSION: This study suggests that reduction of the LEC S1P signaling aggravates lymphedema by enhancing LEC adhesion and amplifying pathogenic CD4 T cell responses. P-selectin inhibitors are suggested as a possible treatment for this pervasive condition. Clinical Perspective: What is New?: Lymphatic-specific S1pr1 deletion exacerbates lymphatic vessel malfunction and Th1/Th2 immune responses during lymphedema pathogenesis. S1pr1 -deficient LECs directly induce Th1/Th2 cell differentiation and decrease anti-inflammatory Treg populations. Peripheral dermal LECs affect CD4 T cell immune responses through direct cell contact.LEC P-selectin, regulated by S1PR1 signaling, affects CD4 T cell activation and differentiation.P-selectin blockade improves lymphedema tail swelling and decreases Th1/Th2 population in the diseased skin.What Are the Clinical Implications?: S1P/S1PR1 signaling in LECs regulates inflammation in lymphedema tissue.S1PR1 expression levels on LECs may be a useful biomarker for assessing predisposition to lymphatic disease, such as at-risk women undergoing mastectomyP-selectin Inhibitors may be effective for certain forms of lymphedema.

13.
Surf Topogr ; 11(1)2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37193116

RESUMO

Textured silicone breast implants with high average surface roughness ("macrotextured") have been associated with a rare cancer of the immune system, Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). Silicone elastomer wear debris may lead to chronic inflammation, a key step in the development of this cancer. Here, we model the generation and release of silicone wear debris in the case of a folded implant-implant ("shell-shell") sliding interface for three different types of implants, characterized by their surface roughness. The "smooth" implant shell with the lowest average surface roughness tested (Ra = 2.7 ± 0.6 µm) resulted in average friction coefficients of µavg = 0.46 ± 0.11 across 1,000 mm of sliding distance and generated 1,304 particles with an average particle diameter of Davg = 8.3 ± 13.1 µm. The "microtextured" implant shell (Ra = 32 ± 7.0 µm) exhibited µavg = 1.20 ± 0.10 and generated 2,730 particles with Davg = 4.7 ± 9.1 µm. The "macrotextured" implant shell (Ra = 80 ± 10 µm) exhibited the highest friction coefficients, µavg = 2.82 ± 0.15 and the greatest number of wear debris particles, 11,699, with an average particle size of Davg = 5.3 ± 3.3 µm. Our data may provide guidance for the design of silicone breast implants with lower surface roughness, lower friction, and smaller quantities of wear debris.

14.
Sci Adv ; 9(8): eabq0435, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36827374

RESUMO

Dysfunction of collecting lymphatic vessel pumping is associated with an array of pathologies. S-(-)-Bay K8644 (BayK), a small-molecule agonist of L-type calcium channels, improves vessel contractility ex vivo but has been left unexplored in vivo because of poor lymphatic access and risk of deleterious off-target effects. When formulated within lymph-draining nanoparticles (NPs), BayK acutely improved lymphatic vessel function, effects not seen from treatment with BayK in its free form. By preventing rapid drug access to the circulation, NP formulation also reduced BayK's dose-limiting side effects. When applied to a mouse model of lymphedema, treatment with BayK formulated in lymph-draining NPs, but not free BayK, improved pumping pressure generated by intact lymphatic vessels and tissue remodeling associated with the pathology. This work reveals the utility of a lymph-targeting NP platform to pharmacologically enhance lymphatic pumping in vivo and highlights a promising approach to treating lymphatic dysfunction.


Assuntos
Vasos Linfáticos , Camundongos , Animais , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Modelos Animais de Doenças , Pressão
15.
Bioinspir Biomim ; 18(3)2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36821859

RESUMO

Peristaltic fluid pumping due to a periodically propagating contraction wave in a vessel fitted with one-way elastic valves is investigated numerically. It is concluded that the valve spacing within the vessel relative to the contraction wavelength plays a critical role in providing efficient pumping. When the valve spacing does not match the wavelength, the valves open asynchronously and the volume of the vessel segments bounded by two consecutive valves changes periodically, thereby inducing volumetric fluid pumping. The volumetric pumping leads to higher pumping flowrate and efficiency against an adverse pressure gradient. The optimum pumping occurs when the ratio of valve spacing to contraction wavelength is about2/3. This pumping regime is characterized by a longer period during which the valves are open. The results are useful for further understanding the pumping features of lymphatic system and provide insight into the design of biomimetic pumping devices.


Assuntos
Modelos Biológicos , Peristaltismo
17.
N Engl J Med ; 388(7): 585-594, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36791159

RESUMO

BACKGROUND: Limited level 1 evidence is available on the omission of radiotherapy after breast-conserving surgery in older women with hormone receptor-positive early breast cancer receiving adjuvant endocrine therapy. METHODS: We performed a phase 3 randomized trial of the omission of irradiation; the trial population included women 65 years of age or older who had hormone receptor-positive, node-negative, T1 or T2 primary breast cancer (with tumors ≤3 cm in the largest dimension) treated with breast-conserving surgery with clear excision margins and adjuvant endocrine therapy. Patients were randomly assigned to receive whole-breast irradiation (40 to 50 Gy) or no irradiation. The primary end point was local breast cancer recurrence. Regional recurrence, breast cancer-specific survival, distant recurrence as the first event, and overall survival were also assessed. RESULTS: A total of 1326 women were enrolled; 658 were randomly assigned to receive whole-breast irradiation and 668 to receive no irradiation. The median follow-up was 9.1 years. The cumulative incidence of local breast cancer recurrence within 10 years was 9.5% (95% confidence interval [CI], 6.8 to 12.3) in the no-radiotherapy group and 0.9% (95% CI, 0.1 to 1.7) in the radiotherapy group (hazard ratio, 10.4; 95% CI, 4.1 to 26.1; P<0.001). Although local recurrence was more common in the group that did not receive radiotherapy, the 10-year incidence of distant recurrence as the first event was not higher in the no-radiotherapy group than in the radiotherapy group, at 1.6% (95% CI, 0.4 to 2.8) and 3.0% (95% CI, 1.4 to 4.5), respectively. Overall survival at 10 years was almost identical in the two groups, at 80.8% (95% CI, 77.2 to 84.3) with no radiotherapy and 80.7% (95% CI, 76.9 to 84.3) with radiotherapy. The incidence of regional recurrence and breast cancer-specific survival also did not differ substantially between the two groups. CONCLUSIONS: Omission of radiotherapy was associated with an increased incidence of local recurrence but had no detrimental effect on distant recurrence as the first event or overall survival among women 65 years of age or older with low-risk, hormone receptor-positive early breast cancer. (Funded by the Chief Scientist Office of the Scottish Government and the Breast Cancer Institute, Western General Hospital, Edinburgh; ISRCTN number, ISRCTN95889329.).


Assuntos
Neoplasias da Mama , Recidiva Local de Neoplasia , Idoso , Feminino , Humanos , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar/efeitos adversos , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Radioterapia Adjuvante , Suspensão de Tratamento , Análise de Sobrevida
18.
Expert Rev Anticancer Ther ; 23(1): 67-86, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36633402

RESUMO

INTRODUCTION: While endocrine therapy is the standard-of-care adjuvant treatment for hormone receptor-positive (HR+) breast cancers, there is also extensive evidence for the role of pre-operative (or neoadjuvant) endocrine therapy (NET) in HR+ postmenopausal women. AREAS COVERED: We conducted a thorough review of the published literature, to summarize the evidence to date, including studies of how NET compares to neoadjuvant chemotherapy, which NET agents are preferable, and the optimal duration of NET. We describe the importance of on-treatment assessment of response, the different predictors available (including Ki67, PEPI score, and molecular signatures) and the research opportunities the pre-operative setting offers. We also summarize recent combination trials and discuss how the COVID-19 pandemic led to increases in NET use for safe management of cases with deferred surgery and adjuvant treatments. EXPERT OPINION: NET represents a safe and effective tool for the management of postmenopausal women with HR+/HER2- breast cancer, enabling disease downstaging and a wider range of surgical options. Aromatase inhibitors are the preferred NET, with evidence suggesting that longer regimens might yield optimal results. However, NET remains currently underutilised in many territories and institutions. Further validation of predictors for treatment response and benefit is needed to help standardise and fully exploit the potential of NET in the clinic.


Assuntos
Neoplasias da Mama , COVID-19 , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante/métodos , Pós-Menopausa , Pandemias , Antineoplásicos Hormonais/uso terapêutico , Receptor ErbB-2
19.
Microcirculation ; 30(2-3): e12792, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36369987

RESUMO

BACKGROUND: Dysfunction of the lymphatic system following injury, disease, or cancer treatment can lead to lymphedema, a debilitating condition with no cure. Despite the various physical therapy and surgical options available, most treatments are palliative and fail to address the underlying lymphatic vascular insufficiency driving lymphedema progression. Stem cell therapy provides a promising alternative in the treatment of various chronic diseases with a wide range of therapeutic effects that reduce inflammation, fibrosis, and oxidative stress, while promoting lymphatic vessel (LV) regeneration. Specifically, stem cell transplantation is suggested to promote LV restoration, rebuild lymphatic circulation, and thus potentially be utilized towards an effective lymphedema treatment. In addition to stem cells, studies have proposed the administration of vascular endothelial growth factor C (VEGFC) to promote lymphangiogenesis and decrease swelling in lymphedema. AIMS: Here, we seek to combine the benefits of stem cell therapy, which provides a cellular therapeutic approach that can respond to the tissue environment, and VEGFC administration to restore lymphatic drainage. MATERIALS & METHODS: Specifically, we engineered mesenchymal stem cells (MSCs) to overexpress VEGFC using a lentiviral vector (hVEGFC MSC) and investigated their therapeutic efficacy in improving LV function and tissue swelling using near infrared (NIR) imaging, and lymphatic regeneration in a single LV ligation mouse tail lymphedema model. RESULTS: First, we showed that overexpression of VEGFC using lentiviral transduction led to an increase in VEGFC protein synthesis in vitro. Then, we demonstrated hVEGFC MSC administration post-injury significantly increased the lymphatic contraction frequency 14-, 21-, and 28-days post-surgery compared to the control animals (MSC administration) in vivo, while also reducing tail swelling 28-days post-surgery compared to controls. CONCLUSION: Our results suggest a therapeutic potential of hVEGFC MSC in alleviating the lymphatic dysfunction observed during lymphedema progression after secondary injury and could provide a promising approach to enhancing autologous cell therapy for treating lymphedema.


Assuntos
Vasos Linfáticos , Linfedema , Células-Tronco Mesenquimais , Animais , Camundongos , Linfangiogênese , Vasos Linfáticos/fisiologia , Linfedema/terapia , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos BALB C , Fator C de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/uso terapêutico , Lentivirus/genética
20.
Arterioscler Thromb Vasc Biol ; 43(1): e1-e10, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36453280

RESUMO

Lymphatic vessels are low-pressure, blind-ended tubular structures that play a crucial role in the maintenance of tissue fluid homeostasis, immune cell trafficking, and dietary lipid uptake and transport. Emerging research has indicated that the promotion of lymphatic vascular growth, remodeling, and function can reduce inflammation and diminish disease severity in several pathophysiologic conditions. In particular, recent groundbreaking studies have shown that lymphangiogenesis, which describes the formation of new lymphatic vessels from the existing lymphatic vasculature, can be beneficial for the alleviation and resolution of metabolic and cardiovascular diseases. Therefore, promoting lymphangiogenesis represents a promising therapeutic approach. This brief review summarizes the most recent findings related to the modulation of lymphatic function to treat metabolic and cardiovascular diseases such as obesity, myocardial infarction, atherosclerosis, and hypertension. We also discuss experimental and therapeutic approaches to enforce lymphatic growth and remodeling as well as efforts to define the molecular and cellular mechanisms underlying these processes.


Assuntos
Vasos Linfáticos , Doenças Metabólicas , Infarto do Miocárdio , Humanos , Linfangiogênese , Vasos Linfáticos/metabolismo , Coração , Infarto do Miocárdio/metabolismo , Doenças Metabólicas/metabolismo
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