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1.
Calcif Tissue Int ; 109(1): 77-91, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33710382

RESUMO

Bone mineral carbonate content assessed by vibrational spectroscopy relates to fracture incidence, and mineral maturity/ crystallinity (MMC) relates to tissue age. As FT-IR and Raman spectroscopy become more widely used to characterize the chemical composition of bone in pre-clinical and translational studies, their bone mineral outcomes require improved validation to inform interpretation of spectroscopic data. In this study, our objectives were (1) to relate Raman and FT-IR carbonate:phosphate ratios calculated through direct integration of peaks to gold-standard analytical measures of carbonate content and underlying subband ratios; (2) to relate Raman and FT-IR MMC measures to gold-standard analytical measures of crystal size in chemical standards and native bone powders. Raman and FT-IR direct integration carbonate:phosphate ratios increased with carbonate content (Raman: p < 0.01, R2 = 0.87; FT-IR: p < 0.01, R2 = 0.96) and Raman was more sensitive to carbonate content than the FT-IR (Raman slope + 95% vs FT-IR slope, p < 0.01). MMC increased with crystal size for both Raman and FT-IR (Raman: p < 0.01, R2 = 0.76; FT-IR p < 0.01, R2 = 0.73) and FT-IR was more sensitive to crystal size than Raman (c-axis length: slope FT-IR MMC + 111% vs Raman MMC, p < 0.01). Additionally, FT-IR but not Raman spectroscopy detected differences in the relationship between MMC and crystal size of carbonated hydroxyapatite (CHA) vs poorly crystalline hydroxyapatites (HA) (slope CHA + 87% vs HA, p < 0.01). Combined, these results contribute to the ability of future studies to elucidate the relationships between carbonate content and fracture and provide insight to the strengths and limitations of FT-IR and Raman spectroscopy of native bone mineral.


Assuntos
Durapatita , Análise Espectral Raman , Carbonatos , Hidroxiapatitas , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Craniofac Surg ; 29(7): 1813-1816, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30192298

RESUMO

Redraping is an increasingly common epicanthoplasty method. However, hooding usually remains at the medial part of the upper eyelid. The authors innovated a modification of redraping epicanthoplasty using excision, resulting in a boomerang-shaped defect that does not lead to hooding of the medial upper eyelid.Medial line (M-line) was drawn at the most medial point of the palpebral fissure. The canthus point (C-point) was marked approximately 1 to 3 mm laterally from the M-point, depending on the amount of widening needed. From the C-point, upper incision was designed to meet the double eyelid line. A V-shaped lower incision was designed 3 to 4 mm below the ciliary margin. A flap was elevated about 7 mm superiorly, 10 mm medially, and 5 mm inferiorly. The elevated skin flap was redraped and the M'-point, which reflected the M-point on the redraped skin, was marked. A curvilinear incision line reflecting previous incision lines was drawn. The crescent-shaped excess skin was excised and the medial canthus was retracted medially, and then the boomerang-shaped defect was observed. The M-point and M'-point were coapted with a suture. The dog-ear at the lower side was trimmed.The 525 patients were followed up for ≥3 months postoperatively. The average increase in the palpebral fissure length was 1.2 ±â€Š0.5 mm. The average decrease in the interepicanthal distance was 2.4 ±â€Š0.9 mm. The average satisfaction score was 4.6 ±â€Š0.6.Boomerang epicanthoplasty can prevent hooding on the medial aspect of the upper eyelid. It is easy to design, requires marking only 1 point, and is tension-free, thereby reducing scar widening.


Assuntos
Blefaroplastia/métodos , Pálpebras/cirurgia , Transplante de Pele/métodos , Retalhos Cirúrgicos , Adolescente , Adulto , Feminino , Humanos , Masculino , Margens de Excisão , Satisfação do Paciente , Resultado do Tratamento , Adulto Jovem
3.
J Craniofac Surg ; 27(3): 741-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27100651

RESUMO

The aim of this study is to see whether the nasojugal groove and wrinkles can be improved following a skin-muscle flap elevation through a subciliary approach to the orbital rim.Fifty-seven patients having fractures of the orbital floor, wall, or orbital rim were included. A subciliary incision was made 3 to 5 mm below the cilia. A skin-muscle flap was elevated and a 5-mm width of the periosteum of the anterior surface of the maxilla was exposed. Thereafter, the origin of the orbicularis oculi muscle was released from the underlying bony origin. An incision was made at the arcus marginalis. After reconstruction, the detached arcus marginalis was sutured to the periosteum of the infraorbital rim and the subciliary incision was closed. Preoperative and postoperative photographs were analyzed with the validated assessment scales for midface.In the 57 sides operated on, the postoperative, mean assessment score was significantly lower (0.56 ±â€Š0.66) on the operated side than on the contralateral side (0.84 ±â€Š1.00) (P = 0.002). In the 37 sides excluding the patients in whom the initial score was 0, and the postoperative, mean assessment score was significantly lower (0.84 ±â€Š0.65) on the operated side than on the contralateral side (1.19 ±â€Š1.05) (P = 0.010).The skin-muscle flap elevated through the subciliary approach to reach the orbital rim improved the nasojugal groove despite the fat removal or repositioning was not performed. The reason for this improvement the authors think is orbicularis oculi muscle had been separated from its origin.


Assuntos
Blefaroplastia/métodos , Retalho Miocutâneo/cirurgia , Órbita/cirurgia , Envelhecimento da Pele , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas Orbitárias/cirurgia , Avaliação de Resultados em Cuidados de Saúde , Adulto Jovem
4.
J Am Chem Soc ; 137(38): 12394-9, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26349620

RESUMO

We report the formation of supramolecular coordination polymers formed from multiporphyrin dendrimers (PZnPM; M = FB or Cu), composed of the focal freebase porphyrin (PFB) or cupper porphyrin (PCu) with eight zinc porphyrin (PZn) wings, and multipyridyl porphyrins (PyPM; M = FB or Cu), PFB or PCu with eight pyridyl groups, through multiple axial coordination interactions of pyridyl groups to PZns. UV-vis absorption spectra were recorded upon titration of PyPFB to PZnPFB. Differential spectra, obtained by subtracting the absorption of PZnPFB without guest addition as well as the absorption of PyPFB, exhibited clear isosbestic points with saturation binding at 1 equiv addition of PyPFB to PZnPFB. Job's plot analysis also indicated 1:1 stoichiometry for the saturation binding. The apparent association constant between PZnPFB and PyPFB (2.91 × 10(6) M(-1)), estimated by isothermal titration calorimetry, was high enough for fibrous assemblies to form at micromolar concentrations. The formation of a fibrous assembly from PZnPFB and PyPFB was visualized by atomic force microscopy and transmission electron microscopy (TEM). When a 1:1 mixture solution of PZnPFB and PyPFB (20 µM) in toluene was cast onto mica, fibrous assemblies with regular height (ca. 2 nm) were observed. TEM images obtained from 1:1 mixture solution of PZnPFB and PyPFB (0.1 wt %) in toluene clearly showed the formation of nanofibers with a regular diameter of ca. 6 nm. Fluorescence emission measurement of PZnPM indicated efficient intramolecular energy transfer from PZn to the focal PFB or PCu. By the formation of supramolecular coordination polymers, the intramolecular energy transfer changed to intermolecular energy transfer from PZnPM to PyPM. When the nonfluorescent PyPCu was titrated to fluorescent PZnPFB, fluorescence emission from the focal PFB was gradually decreased. By the titration of fluorescent PyPFB to nonfluorescent PZnPCu, fluorescence emission from PFB in PyPFB was gradually increased due to the efficient energy transfer from PZn wings in PZnPCu to PyPFB.


Assuntos
Dendrímeros/química , Luz , Polímeros/síntese química , Porfirinas/química , Modelos Moleculares , Polímeros/química
5.
J Craniofac Surg ; 26(6): e525-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26267585

RESUMO

The aim of this systematic review is to summarize and critically evaluate the evidence for or against the effectiveness of restraining devices on facial fractures in motor vehicle collisions (MVCs).In a PubMed search, the search terms "facial bone fracture and seat belt," "facial bone fracture and air bag," and "facial bone fracture and restraining" were used. The authors abstracted the odds ratio (OR) and 95% confidence intervals (CIs) from each study. Weighted mean differences and 95% CIs were also calculated. The statistical analysis was performed with Review Manager (The Nordic Cochrane Centre).The authors found 30 potentially relevant articles, of which 6 articles met our inclusion criteria. Five studies were subgrouped, and a meta-analysis of these data suggested beneficial effects of seat belts on decreasing facial fractures in MVCs (n = 15,768,960, OR, 0.46, 95% CI = 0.35-0.60). Three studies were subgrouped, and a meta-analysis of these data suggested that there were beneficial effects of seat belts and air bags on decreasing facial fractures in MVCs (n = 15,768,021, OR, 0.59, 95% CI = 0.47-0.74). Four studies were subgrouped, and a meta-analysis of these data suggested there were no significant effects of an air bag on decreasing facial fracture in MVCs (n = 15,932,259, OR, 1.00, 95% CI = 0.72-1.39).A seat belt alone (OR, 0.46) or a seat belt and an air bag (OR, 0.59) were effective to decrease facial fractures in MVCs. However, air bags alone had no significant effect (OR, 1.00). In using air bags, seat belt should be applied together to prevent facial fractures in motor vehicle injuries.


Assuntos
Acidentes de Trânsito , Air Bags , Ossos Faciais/lesões , Cintos de Segurança , Fraturas Cranianas/prevenção & controle , Humanos , Veículos Automotores
6.
J Craniofac Surg ; 26(1): 220-1, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25478979

RESUMO

The aim of this systematic review is to summarize and critically evaluate the evidence for or against the effectiveness of restraining devices on eye injury in motor vehicle collisions (MVCs).In a PubMed search, the search terms "eye injury and seatbelt," "eye injury and car belt," "eye injury and airbag," and "eye injury and restraining" were used. Among the 30 potentially relevant articles, 5 articles met our inclusion criteria. The odds ratio (OR) and 95% confidence intervals (CIs) from each study were abstracted. The statistical analysis was performed with Review Manager (The Nordic Cochrane Centre).Three studies were subgrouped, and a meta-analysis of these data suggested no significant effects of an airbag on increasing eye injury in MVCs (n = 10,123,954; OR, 1.10; 95% CI, 0.77-1.56). Two studies were subgrouped, and a meta-analysis of these data suggested that there are beneficial effects of seat belts on decreasing eye injury in MVCs (n = 43,057,271; OR, 0.50; 95% CI, 0.50-0.51).Seat belts were effective to decrease eye injuries in MVCs. However, airbags had no significant effect on an increase to eye injuries. When using airbags, seat belts should be used together.


Assuntos
Air Bags/efeitos adversos , Traumatismos Oculares/prevenção & controle , Cintos de Segurança/efeitos adversos , Acidentes de Trânsito , Traumatismos Oculares/etiologia , Humanos , Veículos Automotores
7.
J Craniofac Surg ; 26(5): e373-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26102541

RESUMO

The aim of this systematic review was to summarize and evaluate the risk of blepharoptosis in contact lens wearers. In a PubMed search, 393 papers were found using the terms "lens and ptosis." The abstracts were read and 16 full text articles were reviewed. Among them, 5 articles were analyzed. Five studies were subgrouped and a meta-analysis of these data suggested there is an increased risk of blepharoptosis in hard contact lens wearers over nonwearers (n = 7426, OR, 17.38, 95% CI = 3.71-81.29, P < 0.00001). One study was subgrouped and these data suggested there is also an increased risk of blepharoptosis in soft contact lens wearers over nonwearers (n = 90, OR, 8.12, 95% CI = 2.68-24.87, P < 0.0002). Patients wearing rigid contact lenses should be advised of the risk of ptosis, and a history of contact lens use should be sought in all patients who have acquired ptosis as the previous authors have recommended.


Assuntos
Blefaroptose/etiologia , Lentes de Contato , Lentes de Contato/efeitos adversos , Lentes de Contato Hidrofílicas/efeitos adversos , Humanos , Fatores de Risco
8.
J Craniofac Surg ; 26(5): 1581-3, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26114513

RESUMO

The aim of this systematic review is to summarize and evaluate the effect of orbital fractures (blowout fractures and nonblowout fractures) on visual acuity. In PubMed search and Scopus search, the terms "orbital fracture OR maxillofacial injury OR facial trauma OR craniofacial fracture," and "visual acuity OR functional outcome OR visual outcome OR improving document of visual acuity OR blindness OR optic nerve neuropathy" were used, which resulted in 1634 and 1152 papers, respectively. Of the 2226 titles excluding 560 duplicated titles, 227 abstracts were reviewed. Of the 227 abstracts reviewed, the authors found 56 potentially relevant full-text articles, of which 5 studies met our inclusion criteria. The odds ratio and 95% confidence intervals from each study were abstracted. The statistical analysis was performed with review manager (The Nordic Cochrane Centre). A summary of 5 studies affirmed that 43 patients among 532 orbital fractures (8.1%) had decreased visual acuity. Twelve patients among 159 blowout fractures (7.5%) had decreased visual acuity. Thirty-one patients among 373 orbital fractures other than pure blowout fractures (8.3%) had decreased visual acuity. In orbital fractures other than pure blowout fractures, the frequency of decreased visual acuity was higher than pure blowout fractures (n = 532, odds ratio, 2.23, 95% confidence interval = 1.06-4.70). Surgeons should acknowledge this with patients before surgery.


Assuntos
Fraturas Orbitárias/complicações , Acuidade Visual/fisiologia , Cegueira/etiologia , Humanos , Doenças do Nervo Óptico/etiologia , Transtornos da Visão/etiologia
9.
J Craniofac Surg ; 26(7): 2211-2, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26468812

RESUMO

We report a case of skin necrosis of the nasal tip after an injection of ribose cross-linked porcine atelocollagen (Evolence; Colbar Life Science Ltd, Herzliya, Israel). A 22-year-old woman had a nasal augmentation. From the glabella to the nasal tip, 10 strokes were injected using 0.6 mL of Evolence. On the day of the injection, her nasal tip became cyanotic; a day after it, an erythematous condition developed and a white cheeselike material appeared. On the second day, it became necrotic. Epithelialization was completed for 2 weeks. Despite laser therapy, permanent scarring of the nasal tip was prominent at the 18-month follow-up. It was thought that the skin necrosis is caused by vascular interruption rather than by hypersensitivity because the skin necrosis was confined to the nasal tip. To avoid vascular interruption from a filler injection, aspiration is needed before injection. The least amount of filler should be released in each stroke with low-pressure injection.


Assuntos
Colágeno/efeitos adversos , Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/efeitos adversos , Nariz/patologia , Pele/patologia , Cicatriz/etiologia , Cicatriz/cirurgia , Colágeno/química , Reagentes de Ligações Cruzadas/química , Cianose/etiologia , Preenchedores Dérmicos/química , Eritema/etiologia , Feminino , Seguimentos , Humanos , Injeções/efeitos adversos , Terapia a Laser , Necrose , Reepitelização/fisiologia , Ribose/química , Adulto Jovem
10.
J Craniofac Surg ; 26(5): 1700-3, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26086928

RESUMO

The aim of this study was to determine the relation of the vector force needed to lift the upper eyelids and the degree of exophthalmos (EX). In the 109 magnetic resonance imaging films, the degree of EX (the shortest distance from the cornea to the line connecting both lateral orbital rims), the anterior angle (θ, an angle formed from the lower margin of the upper eyelid-superior transverse ligament (STL)--with a parallel line connecting the supraorbital rim and the infraorbital rim in the sagittal film), the length from the STL to the upper eyelid margin (levator length [LL]), the thickness of the STL (WT), and the thickness the of levator palpebrae (LT) were measured.The average EX was 14.5 ±â€Š2.35  mm. The average θ was 33.84 ±â€Š2.15 degrees. The vector force needed to lift the upper eyelids (cos θ) was 0.83. The average LL was 21.0 ±â€Š1.54  mm. The average WT was 1.07 ±â€Š0.22  mm. The average LT was 1.69 ±â€Š0.30  mm. There was a significant positive relationship between the EX and age (P = 0.022). The EX in those younger than 20 years (12.8 ±â€Š2.06) was significantly lesser than that of the other age groups. There was no significant relationship between the EX and cos θ. However, there was a significant positive relationship between the EX and the LL. There was a significant positive relationship between LL and LT, and between LL and WT.The farther the eyeball protrudes, the longer the LL is needed. The longer the LL is, the thicker the levator muscle and STL.


Assuntos
Exoftalmia/classificação , Pálpebras/fisiopatologia , Músculos Oculomotores/fisiopatologia , Adulto , Fenômenos Biomecânicos , Piscadela/fisiologia , Cefalometria/métodos , Córnea/patologia , Pálpebras/patologia , Feminino , Humanos , Ligamentos/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Órbita/patologia , Estudos Retrospectivos , Estresse Mecânico , Adulto Jovem
11.
Biomacromolecules ; 15(4): 1382-9, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24598017

RESUMO

Self-assembled polymeric nanocapsules (NCs) that incorporate dendrimer porphyrin (DP) in the shells and superparamagnetic iron oxide nanoparticles (SPIONs) in the cores are fabricated to create a theragnostic platform for the application in photodynamic therapy (PDT) and magnetic resonance imaging (MRI). SPIONs-embedded polystyrene NPs (SPIONs@PS) are used as a template to build up multilayered NCs. The formation of PAH/DP multilayer on the SPIONs@PS is monitored by zeta-pential and fluorescence emission measurement, because the porphyrin unit in the core of DP has strong red fluorescence emission. NCs have strong enough magnetic property (>20 emu/g) for MRI application with typical superparamagnetic behavior, where the linear correlation of R2 and Fe concentration at diluted conditions led to corresponding T2 relaxivity coefficient (r2) value of 93.5 mM(-1) s(-1). Cell viability study upon light irradiation reveals that NCs can successfully work in photosensitizer formulation for PDT.


Assuntos
Imageamento por Ressonância Magnética/métodos , Nanocápsulas/química , Nanotecnologia/métodos , Fotoquimioterapia/métodos , Dendrímeros/química , Compostos Férricos/química , Fluorescência , Células HeLa/efeitos dos fármacos , Humanos , Nanocápsulas/uso terapêutico , Nanocápsulas/toxicidade , Fármacos Fotossensibilizantes/química , Poliaminas/química , Poliestirenos/química , Porfirinas/química , Espécies Reativas de Oxigênio/análise
12.
J Craniofac Surg ; 25(6): e590-2, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25376138

RESUMO

The aims of this study are to report a blowout fracture of the orbital floor and medial wall caused by being struck by a steering wheel knob of an automobile and to discuss the use of airbags and seatbelts as a preventive measure for orbital injuries. A 58-year-old man was struck in the left eye by a steering wheel. His car hit a telephone pole, and he had a frontal collision injury. In this frontal impact, his left eye was hit by a Brodie knob attached to the steering wheel. At the time of injury, the speed of the car was about 65 km/h. He was not wearing a seatbelt, and the airbag had not deployed. Swelling and ecchymosis were observed at the left periorbital area, and he had diplopia on a left-side gaze. A CT revealed fractures in the medial and inferior wall of the left orbit. Entrapped soft tissues were reduced, and the medial wall and floor were reconstructed with a resorbable sheet. His diplopia disappeared 12 days after surgery. To prevent the injury from the steering wheel knob, an airbag should be installed in any vehicle, which has a steering wheel knob. Legislation mandating the use of airbags as well as seatbelts in vehicles with attached steering wheel knobs should be made.


Assuntos
Acidentes de Trânsito , Air Bags , Automóveis , Fraturas Orbitárias/etiologia , Cintos de Segurança , Acidentes de Trânsito/prevenção & controle , Diplopia/etiologia , Equimose/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Orbitárias/etiologia , Fraturas Orbitárias/prevenção & controle , Fraturas Orbitárias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Tomografia Computadorizada por Raios X/métodos
13.
J Craniofac Surg ; 25(3): e267-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24799111

RESUMO

We report a case of an orbital fracture and an eyeball rupture caused by a golf-club injury. A 75-year-old man was struck in his right eye by a golf club while watching behind his son swinging a hybrid-type golf club at his home. A 70-mm muscle-depth laceration was present in the infraorbital area with active bleeding. Computed tomographic imaging of the face revealed a rupture of the right eyeball; fractures in the superior, medial, lateral, and inferior wall of the right orbit; a fracture in the right zygomaticofrontal junction; and a small amount of pneumocephalus in the parafalx region. Under general anesthesia, evisceration of the right eyeball was performed. Not only golfers but also people just watching or passing by can be injured by an errantly struck golf ball or swung golf club. Elderly people as well as children should be instructed in technique and safety and also be supervised when playing golf. Also, the public should be educated about the risk of eye injuries and the benefits of wearing a protective eyewear.


Assuntos
Traumatismos Oculares/etiologia , Golfe/lesões , Fraturas Orbitárias/etiologia , Ferimentos não Penetrantes/complicações , Idoso , Humanos , Masculino , Pneumocefalia/etiologia , Ruptura/etiologia
14.
J Craniofac Surg ; 25(2): 375-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24531252

RESUMO

We experienced and report on a case of retrobulbar hematoma caused by bleeding from the orbital branch of the infraorbital artery after a medial orbital wall reconstruction.A healthy 28-year-old man struck his left eye while playing baseball before admission. A computed tomographic scan revealed an approximately 13 × 12-mm-sized fracture of the left orbit medial wall. The medial orbit wall was reconstructed through a subciliary approach on the 18th day after the injury. Approximately 15 hours after the orbit wall reconstruction, the patient complained of pain in the left orbital area, headache, and vomiting. Upon an examination, swelling and ecchymosis were observed on the left eye. His visual acuity was 0.8 (oculus dexter [OD])/0.4 (oculus sinister [OS]) and the intraocular pressure was 18 (OD)/24 (OS) mm Hg by a Goldmann applanation tonometry. A computed tomographic scan showed an intraorbital hematoma and proptosis on the left side. In an emergency operation, a hematoma with a volume of approximately 2 to 3 mL was evacuated and an active bleeding point was noted on the orbital floor, which was thought to be the orbital branch of the infraorbital nerve. The bleeding point was cauterized. After the operation, his visual acuity was 1.0 (OD)/0.8 (OS) and the ocular pressure normalized to 16 (OD)/16 (OS) mm Hg by a Goldmann applanation tonometry.Close observation and meticulous hemostasis along the infraorbital groove may be needed in an orbital floor exploration to prevent postoperative orbital hematoma.


Assuntos
Beisebol/lesões , Hematoma/etiologia , Fraturas Orbitárias/cirurgia , Procedimentos de Cirurgia Plástica/efeitos adversos , Hemorragia Retrobulbar/etiologia , Adulto , Humanos , Masculino
15.
bioRxiv ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37425743

RESUMO

Tissue stiffness is a critical prognostic factor in breast cancer and is associated with metastatic progression. Here we show an alternative and complementary hypothesis of tumor progression whereby physiological matrix stiffness affects the quantity and protein cargo of small EVs produced by cancer cells, which in turn drive their metastasis. Primary patient breast tissue produces significantly more EVs from stiff tumor tissue than soft tumor adjacent tissue. EVs released by cancer cells on matrices that model human breast tumors (25 kPa; stiff EVs) feature increased adhesion molecule presentation (ITGα 2 ß 1 , ITGα 6 ß 4 , ITGα 6 ß 1 , CD44) compared to EVs from softer normal tissue (0.5 kPa; soft EVs), which facilitates their binding to extracellular matrix (ECM) protein collagen IV, and a 3-fold increase in homing ability to distant organs in mice. In a zebrafish xenograft model, stiff EVs aid cancer cell dissemination through enhanced chemotaxis. Moreover, normal, resident lung fibroblasts treated with stiff and soft EVs change their gene expression profiles to adopt a cancer associated fibroblast (CAF) phenotype. These findings show that EV quantity, cargo, and function depend heavily on the mechanical properties of the extracellular microenvironment.

16.
Cancer Res Commun ; 4(5): 1240-1252, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38630893

RESUMO

Tissue stiffness is a critical prognostic factor in breast cancer and is associated with metastatic progression. Here we show an alternative and complementary hypothesis of tumor progression whereby physiologic matrix stiffness affects the quantity and protein cargo of small extracellular vesicles (EV) produced by cancer cells, which in turn aid cancer cell dissemination. Primary patient breast tissue released by cancer cells on matrices that model human breast tumors (25 kPa; stiff EVs) feature increased adhesion molecule presentation (ITGα2ß1, ITGα6ß4, ITGα6ß1, CD44) compared with EVs from softer normal tissue (0.5 kPa; soft EVs), which facilitates their binding to extracellular matrix proteins including collagen IV, and a 3-fold increase in homing ability to distant organs in mice. In a zebrafish xenograft model, stiff EVs aid cancer cell dissemination. Moreover, normal, resident lung fibroblasts treated with stiff and soft EVs change their gene expression profiles to adopt a cancer-associated fibroblast phenotype. These findings show that EV quantity, cargo, and function depend heavily on the mechanical properties of the extracellular microenvironment. SIGNIFICANCE: Here we show that the quantity, cargo, and function of breast cancer-derived EVs vary with mechanical properties of the extracellular microenvironment.


Assuntos
Neoplasias da Mama , Vesículas Extracelulares , Microambiente Tumoral , Peixe-Zebra , Vesículas Extracelulares/metabolismo , Animais , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Camundongos , Feminino , Metástase Neoplásica , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia
17.
bioRxiv ; 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37904934

RESUMO

Calcium ion-crosslinked alginate hydrogels are widely used as a materials system for investigating cell behavior in 3D environments in vitro . Suspensions of calcium sulfate particles are often used as the source of Ca 2+ to control the rate of gelation. However, the instability of calcium sulfate suspensions can increase chances of reduced homogeneity of the resulting gel and requires researcher's proficiency. Here, we show that ball-milled calcium sulfate microparticles with smaller sizes can create more stable crosslinker suspensions than unprocessed or simply autoclaved calcium sulfate particles. In particular, 15 µm ball-milled calcium sulfate microparticles result in gels that are more homogeneous with a balanced gelation rate, which facilitates fabrication of gels with consistent mechanical properties and reliable performance for 3D cell culture. Overall, these microparticles represent an improved method for alginate hydrogel fabrication that can increase experimental reliability and quality for 3D cell culture.

18.
Jpn J Clin Oncol ; 42(12): 1152-60, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23077243

RESUMO

OBJECTIVE: This study evaluated the outcome of intensity-modulated radiation therapy with simultaneous integrated boost and concurrent chemotherapy for nasopharyngeal cancer. METHODS: We analyzed 53 consecutive nasopharyngeal cancer patients who received definitive treatment using intensity-modulated radiation therapy with simultaneous integrated boost and cisplatin-based concurrent chemotherapy. Forty-six patients were treated with concurrent chemoradiation and seven patients with induction chemotherapy plus concurrent chemoradiation. The gross tumor (PTV(70)) received 69.96 Gy (2.12 Gy/fraction), high-risk subclinical disease (PTV(60)) received 59.4 Gy (1.8 Gy/fraction) and low-risk subclinical disease (PTV(56)) received 56.1 Gy (1.7 Gy/fraction) in 33 fractions. Twenty-eight patients were treated with step-and-shoot intensity-modulated radiation therapy and 25 patients with helical tomotherapy. Dosimetric parameters were compared between the two modalities. RESULTS: The median treatment duration was 49 days (range: 41-65 days). The complete response rate was 92.5%. Three local, two regional, one locoregional and seven distant failures were observed. With the median follow-up of 41 months (range: 8-89 months), the 3- and 5-year local control, locoregional control, disease-free survival and overall survival rates were 91.8 and 91.8%; 87.6 and 87.6%; 77.5 and 70.5%; and 86.4 and 82.1%, respectively. Grade 3 mucositis, dermatitis, leucopenia and grade 4 leucopenia were observed in 10, 1, 2 and 1 patient, respectively. No grade 3 or higher xerostomia occurred. Helical tomotherapy significantly improved dosimetric parameters including the maximum dose, volume receiving >107% of the prescribed dose and uniformity index (D(5)/D(95)). CONCLUSIONS: Intensity-modulated radiation therapy with simultaneous integrated boost with concurrent chemotherapy is a safe and effective treatment modality for nasopharyngeal cancer. Helical tomotherapy has a dosimetric advantage over step-and-shoot intensity-modulated radiation therapy in a clinical setting.


Assuntos
Quimiorradioterapia , Neoplasias Nasofaríngeas/terapia , Radioterapia de Intensidade Modulada/métodos , Adolescente , Adulto , Idoso , Antineoplásicos/administração & dosagem , Quimiorradioterapia/efeitos adversos , Cisplatino/administração & dosagem , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Radioterapia de Intensidade Modulada/efeitos adversos , Segurança , Análise de Sobrevida , Distribuição Tecidual
19.
Biomaterials ; 285: 121540, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35537336

RESUMO

While essential to our understanding of solid tumor progression, the study of cell and tissue mechanics has yet to find traction in the clinic. Determining tissue stiffness, a mechanical property known to promote a malignant phenotype in vitro and in vivo, is not part of the standard algorithm for the diagnosis and treatment of breast cancer. Instead, clinicians routinely use mammograms to identify malignant lesions and radiographically dense breast tissue is associated with an increased risk of developing cancer. Whether breast density is related to tumor tissue stiffness, and what cellular and non-cellular components of the tumor contribute the most to its stiffness are not well understood. Through training of a deep learning network and mechanical measurements of fresh patient tissue, we create a bridge in understanding between clinical and mechanical markers. The automatic identification of cellular and extracellular features from hematoxylin and eosin (H&E)-stained slides reveals that global and local breast tissue stiffness best correlate with the percentage of straight collagen. Importantly, the percentage of dense breast tissue does not directly correlate with tissue stiffness or straight collagen content.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Densidade da Mama , Neoplasias da Mama/patologia , Colágeno , Feminino , Humanos , Mamografia
20.
Jpn J Clin Oncol ; 41(7): 882-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21515609

RESUMO

OBJECTIVE: Various techniques are available for radiotherapy of hepatocellular carcinoma, including three-dimensional conformal radiotherapy, linac-based intensity-modulated radiotherapy and helical tomotherapy. The purpose of this study was to determine the optimal radiotherapy technique for hepatocellular carcinoma. METHODS: Between 2006 and 2007, 12 patients underwent helical tomotherapy for locally advanced hepatocellular carcinoma. Helical tomotherapy computerized radiotherapy planning was compared with the best computerized radiotherapy planning for three-dimensional conformal radiotherapy and linac-based intensity-modulated radiotherapy for the delivery of 60 Gy in 30 fractions. Tumor coverage was assessed by conformity index, radical dose homogeneity index and moderated dose homogeneity index. Computerized radiotherapy planning was also compared according to the tumor location. RESULTS: Tumor coverage was shown to be significantly superior with helical tomotherapy as assessed by conformity index and moderated dose homogeneity index (P= 0.002 and 0.03, respectively). Helical tomotherapy showed significantly lower irradiated liver volume at 40, 50 and 60 Gy (V40, V50 and V60, P= 0.04, 0.03 and 0.01, respectively). On the contrary, the dose-volume of three-dimensional conformal radiotherapy at V20 was significantly smaller than those of linac-based intensity-modulated radiotherapy and helical tomotherapy in the remaining liver (P= 0.03). Linac-based intensity-modulated radiotherapy showed better sparing of the stomach compared with helical tomotherapy in the case of separated lesions in both lobes (12.3 vs. 24.6 Gy). Helical tomotherapy showed the high dose-volume exposure to the left kidney due to helical delivery in the right lobe lesion. CONCLUSIONS: Helical tomotherapy achieved the best tumor coverage of the remaining normal liver. However, helical tomotherapy showed much exposure to the remaining liver at the lower dose region and left kidney.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/radioterapia , Radioterapia Assistida por Computador/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Tomografia Computadorizada Espiral , Resultado do Tratamento
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