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1.
Sci Rep ; 10(1): 8372, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32433520

RESUMO

The regeneration capacity of knee cartilage can be enhanced by applying periosteal grafts, but this effect varies depending on the different sources of the periosteal grafts applied for cartilage formation. Tibia periosteum can be used to enhance cartilage repair. However, long-term analysis has not been conducted. The endochondral ossification capacity of tibia periosteum during cartilage repair also needs to be investigated. In this study, both vascularized and non-vascularized tibia periosteum grafts were studied to understand the relationship between tissue perfusion of the periosteum graft and the effects on cartilage regeneration and bone formation. Furthermore, anti-ossification reagents were added to evaluate the efficacy of the prevention of bone formation along with cartilage regeneration. A critical-size cartilage defect (4 × 4 mm) was created and was covered with an autologous tibia vascularized periosteal flap or with a non-vascularized tibia periosteum patch on the knee in the rabbit model. A portion of the vascularized periosteum group was also treated with the anti-osteogenic reagents Fulvestrant and IL1ß to inhibit unwanted bone formation. Our results indicated that the vascularized periosteum significantly enhanced cartilage regeneration in the cartilage defect region in long-term treatment compared to the non-vascularized group. Furthermore, the addition of anti-osteogenic reagents to the vascularized periosteum group suppressed bone formation but also reduced the cartilage regeneration rate. Our study using vascularized autologous tissue to repair cartilage defects of the knee may lead to the modification of current treatment in regard to osteoarthritis knee repair.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32270767

RESUMO

Background: Linear cutaneous lupus erythematosus is a rare subtype of lupus erythematosus (LE) that develops linear lesions following the lines of Blaschko. Linear cutaneous lupus erythematosus may present as various subtypes of LE, including linear discoid lupus erythematosus. There are few reports about pigmentedlinear discoid lupus erythematosus in the literature. Aims: We aimed to summarize the clinical and pathological features of patients with pigmented linear discoid lupus erythematosus following the lines of Blaschko. Methods: Eighteen patients with pigmented linear discoid lupus erythematosus attending the outpatient department of the Dermatology, Peking Union Medical College Hospital, China, were enrolled in the study. We recorded clinical data including sex, age at onset, disease duration, location and distribution of the lesions, symptoms, trigger factors, antinuclear antibody (ANA) testing, therapy, and therapeutic responses. Histopathological features were also summarized. Results: All 18 patients presented with well-defined brownish pigmented linear or segmental macules or plaques, following the lines of Blaschko. All the lesions were located on the head or neck. Unilaterally distributed lesions were found in 94.4% of patients. Two patients showed low titers of ANA in a speckled pattern. No systemic involvement or progression to systemic LE was noted. The patients were clinically diagnosed as pigmented lichen planus (55.6%), pigmented linear discoid lupus erythematosus (33.3%), and linear morphea (11.1%) before histopathological examination. Limitations: The study was retrospective and direct immunofluorescence was not performed. Not all patients' information was available and 4 patients were lost to follow-up because their contact information was changed. Conclusion: Pigmented linear discoid lupus erythematosus mostly occurs on the head and neck. It manifests as brownish macules along the lines of Blaschko. Differentiation between pigmented linear discoid lupus erythematosus and other dermatoses that have a linear distribution can be difficult both clinically and pathologically, but histological details can help distinguish them.

4.
Toxicol In Vitro ; 62: 104667, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31629901

RESUMO

Serum is an important component in cell culture medium. It also possesses potent antioxidant properties. Therefore, the conventional protocols for detecting reactive oxygen species (ROS) in cultured cells with fluorescent probes include washing and suspending cells with serum-free buffers, such as PBS. This transient serum deprivation is essential for the ROS detecting. Unfortunately, it may also cause unexpected results, which push us to choose more optimal experiment conditions. In the present study, we found an acute lytic cell death induced by xanthohumol (XN), which obstructed ROS detecting in human leukemia cell line HL-60 cells. XN induced ROS burst, caused cell swelling, membrane permeability increase, LDH release, and ultimately an acute lytic cell death and cell rupture. These effects could be alleviated by the antioxidant N-Acetyl-L-cysteine (NAC). Apoptosis, pyroptosis or necroptosis were not observed in this process. Results also indicated that 2% serum addition had already completely scavenged ROS induced by 10 µM XN. Taken together, it is strongly suggested to detecting ROS in a serum-free medium when studying where and how ROS generated in cells. The concentration at the ROS maximum point (10 µM XN in this study) can be selected as the optimal concentration.


Assuntos
Flavonoides/toxicidade , Propiofenonas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Células HL-60 , Humanos , Interleucina-1beta/metabolismo , L-Lactato Desidrogenase/metabolismo , Soro
5.
J Am Chem Soc ; 141(44): 17884-17890, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31602974

RESUMO

Control over core structure is much more challenging than that over shell structure in core-shell silver nanoclusters. Herein, two isostructural chalcogen-mediated [Ag6Z4@Ag36] (Z = S or Se) nanoclusters (SD/Ag42a and SD/Ag42b) caging tetrahedral [Ag6Z4] as cores were synthesized by introducing Ph3CSH or Ph3PSe as slow-release source of S2- or Se2-, respectively, and characterized by single-crystal X-ray diffraction (SCXRD). As compared to the previously reported [AgS4@Ag36] cluster (Ag37), we found that introducing additional S2- or Se2- ions can effectively enlarge the inner core from tetrahedral AgS4 to Ag6Z4, which is a regular octahedron of silver with four Z2- capping on one tetrahedral set of four faces. More interestingly, the molecular enantiomers of SD/Ag42a and SD/Ag42b segregate into different crystals (P212121), while those of Ag37 form racemic crystals (I41/acd). The larger Ag6Z4 core in Ag42 clusters also extends their emission to the near-infrared region (∼760 nm). The study confirms that chalcogenide can enlarge the nuclearity of nanoclusters by altering the inner core structure and affords a new strategy to synthesize chiral core-shell silver nanoclusters of higher-order in controlled fashion.

6.
Dalton Trans ; 48(35): 13305-13314, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31429837

RESUMO

Two novel phosphorescent Ir(iii) complexes, Ir(fom)2(pic) and Ir(fof)2(pic), containing fluorene oxadiazole groups have been synthesized and characterized. The photophysical properties of the complexes have been investigated. Interestingly, both complexes exhibited aggregation-induced phosphorescent emission. The X-ray diffraction study showed that the AIPE properties resulted from weak π-π and C-HN hydrogen-bonding interactions in the aggregated state restricting the rotation of the phenyl groups in the cyclometalating ligands. Owing to the sensitive and selective luminescence quenching of the complexes using picric acid (PA), the complexes were used for PA detection in aqueous media. Additionally, electroluminescence devices have been fabricated using the complexes at 5%-30% doping concentrations. The devices based on Ir(fof)2(pic) obtained the highest luminance 11 877 cd m-2 and current efficiency 23.2 cd A-1, which implied that the incorporation of fluorine could improve the electron affinity and ameliorate the capability of electron injection or transporting.

7.
JAMA Dermatol ; 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31339524
9.
JAMA Dermatol ; 155(7): 845, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31090870
11.
Comput Methods Programs Biomed ; 171: 27-37, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30902248

RESUMO

BACKGROUND AND OBJECTIVES: The calcaneus is the most fracture-prone tarsal bone and injuries to the surrounding tissue are some of the most difficult to treat. Currently there is a lack of consensus on treatment or interpretation of computed tomography (CT) images for calcaneus fractures. This study proposes a novel computer-assisted method for automated classification and detection of fracture locations in calcaneus CT images using a deep learning algorithm. METHODS: Two types of Convolutional Neural Network (CNN) architectures with different network depths, a Residual network (ResNet) and a Visual geometry group (VGG), were evaluated and compared for the classification performance of CT scans into fracture and non-fracture categories based on coronal, sagittal, and transverse views. The bone fracture detection algorithm incorporated fracture area matching using the speeded-up robust features (SURF) method, Canny edge detection, and contour tracing. RESULTS: Results showed that ResNet was comparable in accuracy (98%) to the VGG network for bone fracture classification but achieved better performance for involving a deeper neural network architecture. ResNet classification results were used as the input for detecting the location and type of bone fracture using SURF algorithm. CONCLUSIONS: Results from real patient fracture data sets demonstrate the feasibility using deep CNN and SURF for computer-aided classification and detection of the location of calcaneus fractures in CT images.


Assuntos
Calcâneo/diagnóstico por imagem , Calcâneo/lesões , Aprendizado Profundo , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos
12.
Angew Chem Int Ed Engl ; 58(19): 6276-6279, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30773761

RESUMO

The reaction of {(HNEt3 )2 [Ag10 (tBuC6 H4 S)12 ]}n , Ag2 O, Na2 MoO4 , and m-methoxybenzoic acid (Hmbc) in CH3 OH/CH2 Cl2 led to yellow crystals of [Ag4 S4 (MoO4 )5 @Ag66 ] (SD/Ag70b; SD=SunDi) only, while in the presence of DMF, additional dark-red crystals of [Ag10 @ (MoO4 )7 @Ag60 ] (SD/Ag70a) were obtained. SD/Ag70b consists of five MoO4 2- ions wrapped by a shell of 66 Ag atoms, while SD/Ag70a contains a rare Ag10 kernel consisting of five tetrahedra sharing faces and edges, surrounded by seven MoO4 2- ions enclosed in a shell of 60 Ag atoms. The formation of the Ag10 kernel originates from a reduction reaction during the self-assembly process that involves DMF. This work provides the structural information of a unique Ag10 kernel (five fused Ag4 tetrahedra) and paves an avenue to trap elusive silver species with hierarchical multi-shell silver nanocluster assemblies with the help of anion templates.

14.
World J Clin Cases ; 7(1): 109-115, 2019 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-30637260

RESUMO

BACKGROUND: Ganglioneuroma (GN) is a rare and benign tumor that originates from autonomic nervous system ganglion cells. The most frequently involved sites are the posterior mediastinum, the abdominal cavity, and the retroperitoneal space. It rarely occurs in the cervical area, compressing the spinal cord. Neurofibromatosis type 1 (NF-1) is an autosomal dominant inheritance disorder, whose prevalence rate approximates one per 3000. CASE SUMMARY: We report an extremely rare case of bilateral and symmetric dumbbell GNs of the cervical spine with NF-1. A 27-year-old man with NF-1 presented with a one-year history of gradually progressive right upper extremity weakness and numbness in both hands. Magnetic resonance imaging showed bilateral and symmetric dumbbell lesions at the C1-C2 levels compressing the spinal cord. We performed total resection of bilateral tumors, and the postoperative histopathological diagnosis of the resected mass was GN. After operation, the preoperative symptoms were gradually relieved without complications. To our knowledge, this is the sixth report of cervical bilateral dumbbell GNs. CONCLUSION: In some cases, cervical bilateral dumbbell GNs could be associated with NF-1. The exact diagnosis cannot be obtained before operation, and pathological outcome is the current gold standard. Surgical resection is the most effective option, and disease outcome is generally good after treatment.

16.
Rejuvenation Res ; 22(2): 131-137, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30009679

RESUMO

Kaixin-San (KXS), a Chinese formula, was used to treat "amnesia," a senile dementia in the modern world. This formula was reported to improve behavioral performances in many animal models. This study was designed to explore how KXS has improved amyloid-ß (Aß)-induced memory dysfunction in mice. The mouse models were achieved through unilateral ventricle injection with Aß42. The effects of KXS on memory improvement were evaluated by the step-down test. The electrophysiological changes induced by KXS were measured by long-term potentiation (LTP) analysis in the hippocampus in vivo. The expression of glutamate receptor 2 (GluR2) was observed through immunohistochemical staining. Behavioral experiment outcome demonstrated reduced avoidance time and increased error time during the step-down test in the mice of Aß group. This memory impairment, however, was reversed by KXS. Electrophysiological experiment showed no significant difference between Aß group and KXS group either in the size or the shape of field excitatory postsynaptic potentiation recorded from perforant path to dentate gyrus pathway. However, LTP in this region was reduced by Aß and recovered by KXS administration. Moreover, immunohistochemical staining showed increased postsynaptic GluR2 expression in DG area in KXS group. These findings suggest that Aß results in impairment to memory function of the animals, and KXS protects the animal from memory loss by rescuing LTP through postsynaptic mechanism which refers to increasing GluR2 expression.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Medicamentos de Ervas Chinesas/uso terapêutico , Hipocampo/fisiopatologia , Potenciação de Longa Duração , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/fisiopatologia , Receptores de AMPA/metabolismo , Sinapses/metabolismo , Animais , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Giro Denteado/fisiopatologia , Medicamentos de Ervas Chinesas/farmacologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Camundongos Endogâmicos ICR
17.
Psychon Bull Rev ; 26(1): 250-260, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30066082

RESUMO

The ear and brain interact in an orchestrated manner to create sensations of phantom tones that are audible to listeners despite lacking physical presence in original sounds. The relative contribution of peripheral sensory cell activity and cortical mechanisms to phantom hearing remains elusive. The current study addressed the question of whether non-linear components of a complex signal exist that are not captured by the linear combination of cosines in a series. To this end, we investigated the source and spectro-temporal dynamics of non-linear components within two-tone complexes related to phantom acoustic perception. The empirical mode decomposition, a method for non-linear and non-stationary processes, was applied to extract the extra-aural existence of an oscillatory component within the original signal associated with the phantom sound. This travelling wave (phantom) has never before been observed in the sound's linear spectrum. We showed that the wave travels at a velocity that accurately maps onto the perceived phantom tone frequency. Phase coherence of oscillatory mode dynamics predicted discrimination sensitivity to phantom sounds by listeners. Perceived incidences of phantom tones correlated with magnitude of the Hilbert power spectra of the extra-aural component. Findings suggest a possible origin of phantom sounds that exists within the original signal, with potential implications for current models of non-linear cochlear mechanics and cortical dynamics in generating phantom percepts.


Assuntos
Percepção Auditiva/fisiologia , Estimulação Acústica , Adulto , Feminino , Humanos , Masculino , Modelos Psicológicos
18.
J Coll Physicians Surg Pak ; 28(12): 937-940, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30501831

RESUMO

OBJECTIVE: To prepare neogambogic acid nanoliposomes (GNA-NLC) and study its pharmacokinetics (PK) in rats. STUDY DESIGN: An experimental study. PLACE AND DURATION OF STUDY: Mudanjiang Medical University, Mudanjiang, China, from January 2016 to October 2017. METHODOLOGY: GNA-NLC was prepared by emulsion evaporation-low temperature solidification. The entrapment efficiency, average particle size, and zeta potential were investigated. Male Wistar rats were injected with 1 mg/mL gambogic acid and GNA-NLC into the caudal vein respectively, and the plasma concentration was determined by UPLC- MS/MS. The pharmacokinetic parameters of the two agents were compared. RESULTS: GNA-NLC prepared in this study were mostly spherical spheroids with an average particle size of 146.35 ±1.72 nm, polydispersity coefficient of 0.26 ±0.02, zeta potential of -28.24 ±0.13 MV, entrapment efficiency of 84.63%, and drug loading capacity of 4.23%. DSC showed that neogambogic acid nanoparticles had formed and neogambogic acid was amorphous in the matrix. The pharmacokinetics results in rats showed that GNA-NLC plasma concentration was significantly higher than that of common preparation of gambogic acid, with a half-life period of 10.14 ±0.03 hours, 4.57 times that of gambogic acid. AUC0 ~ 24h of gambogic acid in GNA-NLC lipidosome was 58.36 ±0.23 μg/h/mL, 4.83 times that of gambogic acid. CONCLUSION: GNA-NLC can be prepared successfully by emulsion evaporation-low temperature solidification. The method is simple and easy to control. The GNA-NLC has a long cycle, and high blood concentration, sustained release compared with the raw material gambogic acid.


Assuntos
Composição de Medicamentos , Xantenos/farmacocinética , Animais , Lipossomos , Masculino , Ratos , Ratos Wistar
19.
Ying Yong Sheng Tai Xue Bao ; 29(11): 3541-3549, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30460800

RESUMO

To clarify the sustainable soil reinforcement capacity of the lateral root branches of shrubs after injury by fracture force in a semi-arid coal mining subsidence region of Shendong, we analyzed the ultimate anti-fracture mechanical characteristics of three shrub species, Caragana microphylla, Salix cheilophila, and Hippophae rhamnoides, as well as the self-healing ability of their growth indices and mechanical characteristics after injury by fracture force. The results showed that the anti-fracture force and its strength had significant difference among the three shrub species in their late-ral root branches in the early stage of growing season, with the order of C. microphylla > S. cheilophila > H. rhamnoides. The anti-fracture strengths of C. microphylla and S. cheilophila were positively correlated with the contents of cellulose, lignin and holocellulose, while that of H. rhamnoides was significantly negatively correlated with cellulose and lignin contents, but significantly positively correlated with holocellulose content. The fracture force damage caused by activity in the subsidence area significantly reduced the normal growth and mechanical properties of lateral root branches, which could not return to control levels even after three months of self-healing. For the shrubs, stronger self-healing ability of growth indicators resulted in a higher degree of self-healing of anti-fracture forces. Self-healing ability of growth indicators was in the order of H. rhamnoides (91.2%) > S. cheilophila (82.0%) > C. microphylla (73.9%), and self-healing degree of anti-fracture forces was in the order of H. rhamnoides (41.4%) > S. cheilophila (37.1%) > C. microphylla (30.0%). Sustainable soil reinforcement indices of the shrubs' lateral root branches were in the order of C. microphylla (2.2084) > S. cheilophila (0.2009) > H. rhamnoides (-2.4093). Our results indicated that C. microphylla was the best, S. cheilophila was intermediate, and H. rhamnoides was the least in soil reinforcement in semi-arid coal mining subsidence areas.


Assuntos
Adaptação Fisiológica , Caragana/fisiologia , Hippophae , Mineração , Salix , Estações do Ano , Solo
20.
Hear Res ; 370: 155-167, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30388573

RESUMO

Binaural integration of interaural temporal information is essential for sound source localization and segregation. Current models of binaural interaction have shown that accurate sound localization in the horizontal plane depends on the resolution of phase ambiguous information by across-frequency integration. However, as such models are mostly static, it is not clear how proximate in time binaural events in different frequency channels should occur to form an auditory object with a unique lateral position. The present study examined the spectrotemporal window required for effective integration of binaural cues across frequency to form the perception of a stationary position. In Experiment 1, listeners judged whether dichotic frequency-modulated (FM) sweeps with a constant large nominal interaural delay (1500 µs), whose perceived laterality was ambiguous depending on the sweep rate (1500, 3000, 6000, and 12,000 Hz/s), produced a percept of continuous motion or a stationary image. Motion detection performance, indexed by d-prime (d') values, showed a clear effect of sweep rate, with auditory motion effects most pronounced for low sweep rates, and a punctate stationary image at high rates. Experiment 2 examined the effect of modulation rate (0.5, 3, 20, and 50 Hz) on lateralizing sinusoidally frequency-modulated (SFM) tones to confirm the effect of sweep rate on motion detection, independent of signal duration. Lateralization accuracy increased with increasing modulation rate up to 20 Hz and saturated at 50 Hz, with poorest performance occurring below 3 Hz depending on modulator phase. Using the transition point where percepts changed from motion to stationary images, we estimated a spectrotemporal integration window of approximately 150 ms per octave required for effective integration of interaural temporal cues across frequency channels. A Monte Carlo simulation based on a cross-correlation model of binaural interaction predicted 90% of the variance on perceptual motion detection performance as a function of FM sweep rate. Findings suggest that the rate of frequency channel convergence of binaural cues is essential to binaural lateralization.


Assuntos
Vias Auditivas/fisiologia , Sinais (Psicologia) , Nível de Percepção Sonora , Localização de Som , Estimulação Acústica , Adulto , Simulação por Computador , Testes com Listas de Dissílabos , Feminino , Humanos , Julgamento , Masculino , Modelos Teóricos , Método de Monte Carlo , Mascaramento Perceptivo , Fatores de Tempo , Adulto Jovem
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