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1.
J Biomed Mater Res B Appl Biomater ; 112(10): e35486, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39295151

RESUMO

Hydrogels have emerged as potential materials for bone grafting, thanks to their biocompatibility, biodegradation, and flexibility in filling irregular bone defects. In this study, we fabricated a novel NAH hydrogel system, composed of N,O-carboxymethyl chitosan (NOCC), aldehyde hyaluronic acid (AHA), and hydroxyapatite (HAp). To improve the mechanical strength of the fabricated hydrogel, a porous polycaprolactone (PCL) matrix was synthesized and used as a three-dimensional (3D) support template for NAH hydrogel loading, forming a novel PCL/NAH hybrid scaffold. A mixture of monosodium glutamate (M) and sucrose (S) at varied weight ratios (5M:5S, 7M:3S, and 9M:1S) was used for the fabrication of 3D PCL matrices. The morphology, interconnectivity, and water resistance of the porous PCL scaffolds were investigated for optimal hydrogel loading efficiency. The results demonstrated that PCL scaffolds with porogen ratios of 7M:3S and 9M:1S possessed better interconnectivity than 5M:5S ratio. The compressive strength of the PCL/NAH hybrid scaffolds with 9M:1S (561.6 ± 6.1 kPa) and 7M:3S (623.8 ± 6.8 kPa) ratios are similar to cancellous bone and all hybrid scaffolds were biocompatible. Rabbit models with tibial defects were implanted with the PCL/NAH scaffolds to assess the wound healing capability. The results suggest that the PCL/NAH hybrid scaffolds, specifically those with porogen ratio of 7M:3S, exhibit promising bone healing effects.


Assuntos
Regeneração Óssea , Quitosana , Durapatita , Ácido Hialurônico , Hidrogéis , Poliésteres , Alicerces Teciduais , Quitosana/química , Quitosana/farmacologia , Quitosana/análogos & derivados , Animais , Coelhos , Durapatita/química , Durapatita/farmacologia , Alicerces Teciduais/química , Regeneração Óssea/efeitos dos fármacos , Poliésteres/química , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Teste de Materiais , Masculino
2.
JAMA ; 331(21): 1856-1857, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38717779

RESUMO

A 3-year-old had spontaneous gingival hemorrhage and bilateral limb weakness with inability to bear weight. He had no preceding oral trauma or recent infection, took no regular medications, and had no recent use of aspirin or nonsteroidal anti-inflammatory drugs; his diet was limited to primarily chicken nuggets and milk. What is the diagnosis and what would you do next?


Assuntos
Ácido Ascórbico , Hemorragia Gengival , Dor Musculoesquelética , Escorbuto , Pré-Escolar , Humanos , Masculino , Diagnóstico Diferencial , Hemorragia Gengival/sangue , Hemorragia Gengival/diagnóstico , Hemorragia Gengival/etiologia , Dor Musculoesquelética/sangue , Dor Musculoesquelética/diagnóstico , Dor Musculoesquelética/etiologia , Escorbuto/sangue , Escorbuto/complicações , Ácido Ascórbico/sangue
3.
Quintessence Int ; 54(8): 652-657, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37313575

RESUMO

Dentinogenic ghost cell tumor (DGCT) is an uncommon odontogenic tumor considered to be the solid, tumorous variant of calcifying odontogenic cyst. DGCT is characterized by islands of ameloblastoma-like epithelial cells that resemble the enamel organ, the presence of ghost cells, and dentinoid material. This article reports a rare case of dentinogenic ghost cell tumor associated with an odontoma in an adult patient, with a review of the literature. To the best of the authors' knowledge, there have only been four case reports of DGCT associated with odontoma, all of which occurred in children and adults younger than 30 years old.


Assuntos
Ameloblastoma , Cisto Odontogênico Calcificante , Tumores Odontogênicos , Odontoma , Adulto , Criança , Humanos , Odontoma/complicações , Odontoma/diagnóstico por imagem , Odontoma/cirurgia , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/cirurgia , Tumores Odontogênicos/patologia , Cisto Odontogênico Calcificante/diagnóstico por imagem , Cisto Odontogênico Calcificante/cirurgia , Cisto Odontogênico Calcificante/patologia , Ameloblastoma/diagnóstico por imagem , Ameloblastoma/cirurgia , Ameloblastoma/patologia
4.
JAMA Otolaryngol Head Neck Surg ; 149(7): 647-648, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37289465

RESUMO

A 46-year-old man presented for an evaluation of a lesion on the dorsal tongue; he was asymptomatic and unaware of the lesion prior to it being discovered by his dentist. What is your diagnosis?


Assuntos
Neoplasias da Língua , Língua , Humanos , Neoplasias da Língua/diagnóstico , Neoplasias da Língua/cirurgia
5.
Head Neck Pathol ; 17(2): 562-570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36480092

RESUMO

BACKGROUND: Sclerosing odontogenic carcinoma is an exceedingly rare gnathic malignancy first described by Koutlas et al. in 2008, and was only recently designated as a distinct pathologic entity by World Health Organization in the 2017 Classification of Head and Neck Tumors. To date, fewer than fifteen cases of this neoplasm have been reported in the English language literature. This tumor is characterized by thin cords, strands, and small nests of epithelium in a densely sclerotic stroma. In some tumor foci, the density of the stroma may be sufficient to compress the epithelial component beyond detection in the absence of immunohistochemistry, thus rendering this entity a particularly challenging diagnosis in small sample sizes. METHODS: A 55-year-old male presented with an asymptomatic lesion of posterior left maxilla. Cone beam computed tomography (CBCT) demonstrated a large, well-defined bony lesion with scalloped border, spanning from canine to first molar. External root resorption of the adjacent teeth was also noted. Microscopic examination of the biopsy specimen revealed an odontogenic tumor with features consistent with sclerosing odontogenic carcinoma. Immunohistochemical staining was performed to confirm the diagnosis. RESULTS: The tumor was positive for CK5/6, CK19, E-cadherin, p63 and negative for CK20 and CK7. CONCLUSION: Sclerosing odontogenic carcinoma is a rare, low-grade malignancy of odontogenic origin, which represents a diagnosis of exclusion in many cases. An immunohistochemical profile demonstrating positivity for markers including CK5/6, CK19, p63, and E-cadherin, in addition to a set of pertinent negative findings, can aid in the diagnosis of this tumor. This entity appears to lack metastatic potential despite its locally destructive behavior and a common histologic finding of perineural invasion.


Assuntos
Carcinoma , Neoplasias Bucais , Tumores Odontogênicos , Masculino , Humanos , Tumores Odontogênicos/patologia , Maxila/patologia , Neoplasias Bucais/patologia , Epitélio/patologia , Carcinoma/patologia
7.
J Toxicol ; 2022: 7781723, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091101

RESUMO

Mice were used in in vivo experiments to evaluate the effects of doses of n-hexane extract (from 100 to 1,300 mg/kg body weight/day) on the ability to control obesity, blood glucose, and blood lipid. In this study, body weight gain, caloric intake, glucose tolerance, blood lipid, histopathological study, and locomotion activity were examined. Furthermore, this study evaluated the lethality of the extract in extremely high doses in the tested mice. After 3 months of use with an extremely high dose of 5,000 mg/kg body weight/day (equivalent to 350 g/day for a 70 kg person), no animals with abnormal conditions or death were observed. This initially demonstrated the safety of the extract. In addition, after 6 weeks of testing on high-fat diet-induced obese mice, n-hexane extract at a dose of 500 mg/kg body weight/day (equivalent to 35 g/day for a 70 kg person) demonstrated a positive effect on the ability to control obesity, blood glucose, and blood lipid through the results of body weight, blood lipids, glucose tolerance, and histopathology (white fat, liver, and kidney tissues). In this study, n-hexane extract from the roots of Duong-dau tree has proven to be strongly biologically active in preventing and supporting the treatment of diseases related to overweight and obesity, helping to control blood glucose levels thereby reducing the risk of type 2 diabetes.

8.
Int J Food Sci ; 2021: 4880603, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34532496

RESUMO

Five Vietnamese rice varieties, which differ in their basic chemical composition (starch content, amylose content, fiber content) including polished rices and whole grain rices, were chosen for this study. High-fat diet-induced obesity, using these rice, was subjected to in vivo experiments to evaluate the effects of body weight gain, caloric intake, postprandial blood glucose level (PBGL), and glycemic index (GI) in tested mice groups. PBGL peaks appeared at 30th minute after eating, and GI of each experimental group was ranked in order as GN > TL > HR > GM > LD and GN > LT > HR > LD > GM, respectively, in which, brown rice (LD) and germinated brown rice (GM) had low GI. Furthermore, these rice varieties caused the lowest LDL cholesterol and the ratio of LDL/HDL cholesterols in mice. In this study, the higher the amylose and fiber contents were, the lower glycemic index, triglycerides, LDL, and LDL/HDL values were. The golden flower glutinous rice (GN), with low amylose and fiber content, gave worse blood lipid parameters than that of GM and LD. Histopathological studies of white adipose and liver tissues showed that LD and GM significantly reduced the symptoms of obesity and fatty liver compared with the others, especially compared to GN. The results obtained from this study help patients with overweight, obesity, and type 2 diabetes choose the right rice variety for their daily diet to be able to control their diseases.

9.
JAC Antimicrob Resist ; 3(3): dlab103, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34322671

RESUMO

BACKGROUND: MDR bacteria including carbapenem-resistant Pseudomonas aeruginosa are recognized as an important cause of hospital-acquired infections worldwide. This investigation seeks to determine the molecular characterization and antibiotic resistance genes associated with carbapenem-resistant P. aeruginosa. METHODS: We conducted WGS and phylogenetic analysis of 72 carbapenem-resistant P. aeruginosa isolated from hospital-acquired infection patients from August 2011 to March 2015 in three major hospitals in Hanoi, Vietnam. RESULTS: We identified three variants of IMP gene, among which bla IMP-15 was the most frequent (n = 34) in comparison to bla IMP-26 (n = 2) and bla IMP-51 (n = 12). We observed two isolates with imipenem MIC >128 mg/L that co-harboured bla IMP-15 and bla DIM-1 genes and seven isolates (imipenem MIC > 128 mg/L) with a bla KPC-1 gene from the same hospital. MLST data shows that these 72 isolates belong to 18 STs and phylogenetic tree analysis has divided these isolates into nine groups. CONCLUSIONS: Our results provide evidence that not only bla IMP-26 but other IMP variants such as bla IMP-15 and bla IMP-51 genes and several STs (ST235, ST244, ST277, ST310, ST773 and ST3151) have been disseminating in healthcare settings in Vietnam. In addition, we report the emergence of two isolates belonging to ST1240 and ST3340 that harboured two important carbapenemase genes (bla IMP-15 and bla DIM-1) and seven isolates belonging to ST3151 of P. aeruginosa that carried the bla KPC-1 gene in Vietnam, which could potentially cause serious restricted availability of treatment options in healthcare settings.

10.
Int J Food Sci ; 2019: 9290627, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31192252

RESUMO

Cassava starch was oxidized using the electrolysis system. Sodium chloride was added to this system at various concentrations from 0.5 to 5.0 % (w/v). The whiteness of modified starches proportionally increased based on the NaCl concentration and human eyes could recognize the difference of color. Under treatment, dents occurred on the surface of starch granule. Concentration of carbonyl and carboxyl groups was increased compared to native starch. Based on X-ray diffraction pattern, oxidized starch kept its A-type. Besides, the ratios of alpha-helix/amorphous regions remained indicating oxidation reaction mainly subjected on amorphous region. Intrinsic viscosity was used to indirectly calculate the average molecular weight of sample. Furthermore, results showed that average molecular weight was significantly reduced (from 2.09-fold to 13.22-fold) based on the reacting NaCl concentration. The increase of NaCl content related to the increase of retrogradation of treated starches. At various temperatures (30-95°C), swelling factor and clarity reflected negative and positive correlations to NaCl concentration.

11.
Smart Mater Struct ; 28(5)2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-33479558

RESUMO

Ultralight materials present an opportunity to dramatically increase the efficiency of load-bearing aerostructures. To date, however, these ultralight materials have generally been confined to the laboratory bench-top, due to dimensional constraints of the manufacturing processes. We show a programmable material system applied as a large-scale, ultralight, and conformable aeroelastic structure. The use of a modular, lattice-based, ultralight material results in stiffness typical of an elastomer (2.6 MPa) at a mass density typical of an aerogel (5.6 m g c m 3 ). This, combined with a building block based manufacturing and configuration strategy, enables the rapid realization of new adaptive structures and mechanisms. The heterogeneous design with programmable anisotropy allows for enhanced elastic and global shape deformation in response to external loading, making it useful for tuned fluid-structure interaction. We demonstrate an example application experiment using two building block types for the primary structure of a 4.27m wingspan aircraft, where we spatially program elastic shape morphing to increase aerodynamic efficiency and improve roll control authority, demonstrated with full-scale wind tunnel testing.

12.
J Food Sci Technol ; 52(12): 7640-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604340

RESUMO

Gelatinized starches were recrystallized under hydrothermal treatment and their properties were characterized by X-ray diffractometry, solid-state (13)C cross-polarization and magic-angle spinning nuclear magnetic resonance, differential scanning calorimetry, gel-permeation chromatography, high-performance anion-exchange chromatography using pulsed amperomeric detection, high-performance size-exclusion chromatography with attached multiangle laser light scattering and refractive index detectors, and digestibility analysis. Amylopectin molecules of hylon (V, VII) and water yam starch contained long side-chains with high proportion of fb1 and fb2. Under hydrothermal treatment, the double helix proportion and relative crystallinity significantly increased and reached maxima of water yam (48.7 and 28.2 %, respectively). Except water yam starch, X-ray diffraction pattern of all starches exhibited the evidence of type 2 amylose-lipid complex. Besides, under DSC measurement, potato and hylon starches showed the endotherm of amylose-amylose interaction. The hydrothermal treatment caused the recrystallization resulting in the decrease of RDS, especially in case of hylon and water yam starch. HTT water yam contained highest SDS (48.3 %) and HTT hylon VII contained highest RS (44.5 %). The relationship between structure and digestibility was observed, in which, high amylose content and specific structures of amylopectin molecule were necessary for the production of RS and/or SDS of hydrothermally treated starches.

13.
J Food Sci ; 77(6): C574-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22582811

RESUMO

UNLABELLED: Gelatinized water yam starch was subjected to hydrothermal treatment (25, 30, and 35% moisture content for 1, 8, 16, and 24 h at 100 °C) and characterized by X-ray diffractometry, solid-state ¹³C cross-polarization and magic-angle spinning nuclear magnetic resonance, differential scanning calorimetry, and digestibility analysis. The slowly digestible starch (SDS) content of the starch treated at 30% moisture content for 24 h reached 49.1%, 31.9% higher than that of the control starch. The B-type pattern of native starch was re-crystallized to the A-type by hydrothermal treatment. The SDS content showed negative correlations with T(o), T(p), T(c), and T(r), but showed a positive correlation with melting enthalpy. Furthermore, SDS was positively correlated with hydrothermal reaction time, moisture content, relative crystallinity, and the double-helix proportion. The structural changes in hydrothermally treated water yam starches resulted in the enhancement of SDS. PRACTICAL APPLICATION: The hydrothermally treated water yam starch could be used as a food ingredient for slow-energy supply or dietary fiber.


Assuntos
Fibras na Dieta/análise , Digestão , Dioscorea/química , Manipulação de Alimentos/métodos , Tubérculos/química , Amido/química , Água/análise , Varredura Diferencial de Calorimetria , Configuração de Carboidratos , Fenômenos Químicos , Fibras na Dieta/metabolismo , Alimentos Fortificados/análise , Géis , Temperatura Alta , Ressonância Magnética Nuclear Biomolecular , Transição de Fase , Polarografia , República da Coreia , Amido/isolamento & purificação , Amido/metabolismo , Fatores de Tempo , Vietnã , Difração de Raios X
14.
J Dairy Res ; 74(1): 106-15, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17214913

RESUMO

Age thickening is a well known phenomenon within the dairy industry, where the apparent viscosity of concentrated dairy solutions increases with storage time under low shear. The objective of the paper is to develop new tools to analyse several aspects of age thickening, including the increases in shear thinning, the degree of thixotropy and the rate of structural build up with time, as well as irreversible structural changes and gelation. The build up of the dispersed phase structure during storage, was captured by a snap shot technique, where concentrated milk samples were stored, and aliquots were taken at periodic intervals and subjected to shear sweep tests to collect flow curves. Rheological modelling using the Herschel-Bulkley model showed an increase in yield stress and consistency, indicating a build up in structure during age thickening. The trend in apparent viscosity with storage time showed two-phases, a slow and steady increase followed by a sharp rise, which could be used to identify the onset of firm gelation. The extrapolated viscosity at infinite shear rate increased with storage time, indicating the build up in irreversible structural components during age thickening.


Assuntos
Leite/química , Reologia , Animais , Bovinos , Conservação de Alimentos , Fatores de Tempo , Viscosidade
15.
J Dairy Res ; 74(1): 116-23, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17214912

RESUMO

This work investigated the combined effect of solids content, heating and storage temperatures on the rheological behaviour of reconstituted whole milk concentrates. The powder was reconstituted at 35 degrees C in a custom built recombination rig to various total solids content (TS) from 10-48% TS. The concentrates were then heated to 45-85 degrees C and stored at the heating temperature. The rheological behaviour shifter from Newtonian behaviour (below 30% TS) to power law (below 40% TS), with the yield stress observed from 40% TS upwards and time-dependent behaviour was noticed above 44% TS. Higher heating temperatures tend to promote non-Newtonian behaviour at lower solids content. The viscosity-solid content curve showed an exponential relationship, while the viscosity-temperature curve exhibited a minimum at 65-75 degrees C above 46% TS. During age thickening, the yield stress and the consistency coefficient increased, while the flow behaviour index decreased with storage time. This indicated that the milk concentrates deviated away from Newtonian behaviour during age thickening.


Assuntos
Proteínas do Leite/análise , Leite/química , Reologia , Temperatura , Animais , Bovinos , Conservação de Alimentos , Fatores de Tempo , Viscosidade
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