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1.
J Med Invest ; 70(3.4): 524-529, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37940544

RESUMO

OBJECTIVES: The aim of the present study was to introduce a novel three-dimensional computed tomography (3DCT)-based three-column classification (named "MLP classification system") of intertrochanteric fractures and evaluate its reproducibility and reliability. METHODS: From September 2020 to September 2022, a total of 258 consecutive patients (60 male, 198 female;mean age 81.3 years) with intertrochanteric fractures were included in this study. The fracture in each case was assessed using a novel three-dimensional computed tomography-based three-column classification. Two examiners tested the intra and inter-observer reliability of this new classification system using kappa variance. RESULTS: The intertrochanteric region was divided into the medial column, lateral column, and posterior column. Intertrochanteric fractures were documented as M0/1/2L0/1/2/3P0/1/2/3. All fractures were classifiable into the new classification system. The intra-observer kappa values were 0.91 and 0.89, while the inter-observer kappa value was 0.82, both indicating almost perfect reliability. CONCLUSION: This novel 3DCT-based MLP classification system for intertrochanteric fractures is comprehensive, and reproducible with good agreement. It is based on proximal femur biomechanic characteristics and traumatic mechanism, contributing to formulating more reasonable treatment protocols involving various late-model internal fixation devices. J. Med. Invest. 70 : 524-529, August, 2023.


Assuntos
Fraturas do Quadril , Imageamento Tridimensional , Humanos , Masculino , Feminino , Idoso de 80 Anos ou mais , Reprodutibilidade dos Testes , Variações Dependentes do Observador , Tomografia Computadorizada por Raios X/métodos , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia
2.
Opt Express ; 29(6): 8676-8684, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820310

RESUMO

Terahertz (THz) radiation from an inhomogeneous plasma filament generated by focusing two-color femtosecond laser pulses into argon gas filled in a chamber is investigated experimentally by tailoring the Gaussian pump laser beams with an iris, where broadband THz emission over 10 THz is produced. It is found that the collected far-field THz radiation includes not only coherent but also partial-coherent components of the THz waves, which are emitted from the different parts of the inhomogeneous plasma filament with different plasma densities, contributing correspondingly to the different frequencies of the THz spectrum. Our results suggest that the THz spectrum can be manipulated by controlling the plasma density distribution of the filaments.

3.
Diagn Pathol ; 15(1): 22, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164751

RESUMO

BACKGROUND: Extraovarian Brenner tumors (EOBTs) are extremely rare and can be observed incidentally in both female and male patients, raising concerns regarding the origin of Brenner tumors. CASE PRESENTATION: A 53-year-old postmenopausal woman presented with a nodular lesion in the left side of the corpus uteri, which was found at a routine health check. Macroscopically, the lesion appeared as a solid nodule with a yellowish-gray cut surface, approximately 6 cm in greatest diameter. Microscopically, the lesion consisted of well-defined epithelial nests and spindled stromal cells. Parenchymal cells expressed CK7, GATA3, CK5/6, 34ßE12, and p63. A single layer of cavity-lined cells with umbrella-like shape showed apical Uroplakin III positivity. Stromal cells were positive for SMA, ER, and PR. The final diagnosis was EOBT and the patient was followed for 2 months with no recurrence. CONCLUSIONS: We report here the third case of EOBTs in the uterus. The combination of morphologic and immunohistochemical results supported the involvement of urothelial metaplasia in the development of EOBTs. The similarities between EOBTs and Walthard nests made Müllerian epithelium an attractive candidate as the cellular origin. Changes of tissue structure or sex hormones imbalance may lead to the translocation of Müllerian remnants to distant organs, explaining the pathogenesis of EOBTs.


Assuntos
Tumor de Brenner/patologia , Neoplasias Uterinas/patologia , Feminino , Humanos , Pessoa de Meia-Idade
4.
Sensors (Basel) ; 19(5)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866443

RESUMO

Terahertz time-domain spectroscopy (THz-TDS) is an effective coherent detection technique for deeply understanding the structures and functions of biomolecules. However, generally not full information in the whole THz range can be obtained due to the limited detection bandwidth (usually less than 5 THz) of the traditional THz-TDS systems. In this paper, effective THz absorption spectra in 0.5⁻10 THz range of five typical nucleobases of DNA/RNA are characterized with a super broadband THz detection technique, called the air-biased- coherent-detection (THz-ABCD) technique. Few unexpected characteristic absorption peaks appeared in the low-frequency region and meanwhile a series of anticipated characteristic absorption peaks are found in the high-frequency region. The fingerprint spectra of these nucleobases are helpful for further analysis on the vibration and twisting behavior of hydrogen bonds, van der Waals and electrostatic forces etc. between and within DNA/RNA biomolecules.

5.
J Cell Physiol ; 234(9): 15537-15547, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30779115

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most prevalent reproductive disorders in women worldwide. Despite rigorous research, the exact molecular mechanism that governs PCOS pathogenesis remains unclear. To investigate the potential roles of circular RNAs (circRNAs), this study sequenced ribosomal RNA-depleted total RNA from exosomes of follicle fluids obtained from PCOS patients using non-PCOS samples as controls. Bioinformatic analysis identified 167 upregulated and 245 downregulated circRNAs from a total of 16,771 detected candidates. Functional analysis suggests that pathways related to bacterial infection, associated chronic inflammation, and oxidative stress could be targeted by the differential circRNAs in PCOS patients. The obtained sequencing results were further validated by quantitative reverse-transcription polymerase chain reaction and a circRNA-microRNA interaction network was constructed. The obtained results provide a valuable addition to the published studies on the mechanism of PCOS pathogenesis by revealing a wide variety of new circRNAs, miRNA, and gene targets that merit further investigation.

6.
Toxicon ; 160: 23-28, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30772435

RESUMO

Phytoremediation with aquatic macrophyte has been considered as an eco-friendly technique for controlling harmful cyanobacteria outbreak and proven to be effective. The conventional water quality parameters are frequently measured to evaluate the effectiveness of phytoremediation. However, the concentration of microcystin-leucine-arginine (MC-LR) in different vegetated water still remains uncertain. In this study, the contents of MC-LR in four macrophyte-vegetated lagoons were determined by solid phase extraction and ultra-high-performance liquid chromatography with tandem mass spectrometry technology. Results indicated that MC-LR was found in Nymphaea tetragona lagoon (lagoon-S), Vallisneria spiralis lagoon (lagoon-B) and another Vallisneria spiralis lagoon (lagoon-J). Only in lagoon dominated by Pistia stratiotes L. (lagoon-D), MC-LR concentration was undiscovered regardless of seasonal variation. The levels of MC-LR varied seasonally and were affected by the different vegetated aquatic macrophytes. The results suggest that in addition to conventional physicochemical parameters and indicators of water quality, MC-LR levels should be taken into consideration when the effectiveness of phytoremediation is assessed.


Assuntos
Biodegradação Ambiental , Microcistinas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Araceae , Cromatografia Líquida de Alta Pressão , Hydrocharitaceae , Toxinas Marinhas , Nymphaea , Estações do Ano , Espectrometria de Massas em Tandem , Águas Residuárias , Purificação da Água/métodos
7.
Rev Sci Instrum ; 88(9): 093104, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28964165

RESUMO

We demonstrate theoretically and experimentally a coherent terahertz detection technique based on an optically biased field functioning as a local oscillator and a second harmonic induced by the terahertz electric field in the air sensor working in free space. After optimizing the polarization angle and the energy of the probe pulse, and filling the system with dry nitrogen, the terahertz radiation generated from a two-color-femtosecond-laser-pulses induced plasma filament is measured by this technique with a bandwidth of 0.1-10 THz and a signal-to-noise ratio of 48 dB. Our technique provides an alternative simple method for coherent broadband terahertz detection.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1277-83, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-29999283

RESUMO

Terahertz Time-Domain Spectroscopy (THz-TDS) is one of the effective coherent detection techniques. It has been widely applied in materials, chemistry, biology, security and other fields due to its capabilities such as high signal-to-noise ratio (SNR), broadband detection, working at room temperature, time resolved measurement and others. Limited by the spectrum bandwidth of THz radiation and detection techniques, the measuring range of the traditional THz-TDS system is generally less than several THz, thus the spectral information of high frequencies cannot be obtained. In order to expand its application, there is an urgent need for the development of ultra-broadband (≥10 THz) THz-TDS detection techniques. This paper reviews the development and applications of main detection techniques in ultra-broadband THz-TDS. The advantages and disadvantages of these techniques are also analyzed.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2031-5, 2016 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30035870

RESUMO

Osteoarthritis is a common arthritis disease caused by cartilage tissue damage and degeneration, which is one of the large epidemics that affect human health. The early detection of the pathological changes of articular cartilage can greatly improve the cure rate of disease, but the relevant clinical diagnosis technology has not been developed. In recent years, the applications and researches of terahertz technology are increasingly valued and it has drawn great attention in the field of medicine. Compared with traditional methods, the terahertz radiation is low-energy and non-ionizing whose spectral-fingerprinting capability is well-known in the biological world. Meanwhile, THz technology has a great potential in diagnosis of articular cartilage early degeneration. This paper briefly introduces the physiological and pathological conditions of the articular cartilage, the current clinical techniques of articular cartilage detection. It mainly summarizes the terahertz technology used for detecting articular cartilage, including detection of animal and human cartilage respectively. At last, the challenges and development prospects of terahertz technology in articular cartilage detection are discussed.


Assuntos
Cartilagem Articular , Animais , Humanos , Osteoartrite , Radiação Terahertz
10.
J Huazhong Univ Sci Technolog Med Sci ; 35(6): 851-857, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26670435

RESUMO

The aim of this study was to investigate the changes of iron levels and hepatic regulatory molecules expression involved in iron metabolism in non-diabetic obese/type 2 diabetic rat models. Male Wistar rats were divided into 3 groups: control group, non-diabetic obese group and type 2 diabetic group (n=20 each). The rats were evaluated physiologically and biochemically. The hepatic histopathological changes were observed using haematoxylin and eosin (HE) staining. The mRNA expression patterns of hepcidin, interleukin-6 (IL-6), hypoxia-inducible factor (HIF) and ferroportin (Fpn) in the rat liver in control group, non-diabetic obese group and type 2 diabetic group were analyzed by real-time RT-PCR. The protein expression patterns of hepcidin in liver of each group were further analyzed by immunohistochemistry and Western blotting. As compared with control group, the ferritin in non-diabetic obese group and type 2 diabetic group was increased significantly (P<0.001). However, there was no significant difference in soluble transferring receptor (sTfR):ferritin ratio among the three groups (P>0.05). The real-time RT-PCR, immunohistochemistry and Western blotting results all revealed that the expression levels of hepcidin in non-diabetic obese group and type 2 diabetic group were elevated significantly as compared with those in control group (P<0.001). The expression levels of hepcidin mRNA between non-diabetic obese group and type 2 diabetic group showed no significant difference (P>0.05). However, the protein expression levels of hepcidin in type 2 diabetic group were significantly higher than those in non-diabetic obese group (P<0.05). Compared to control group, the expression levels of IL-6 mRNA in non-diabetic obese group and type 2 diabetic group were increased significantly and the expression levels of Fpn mRNA decreased (P<0.05). However, the expression levels of HIF mRNA had no significant difference among three groups. It is suggested that iron metabolism is substantially disturbed in non-diabetic obese and type 2 diabetic rats probably by the abnormal expression of hepcidin in chronic inflammatory status. The increased hepcidin may restrain the iron release from the cells by affecting the expression of Fpn, which probably associates with the development of diabetic complication.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Hepcidinas/metabolismo , Ferro/metabolismo , Obesidade/metabolismo , Animais , Diabetes Mellitus Tipo 2/complicações , Hepcidinas/genética , Interleucina-6/genética , Masculino , Obesidade/complicações , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
11.
Opt Express ; 20(25): 27756-65, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-23262721

RESUMO

We present a planar waveguide model and a mechanism based on standing wave resonances to interpret the unity absorptions of ultrathin planar metamaterial absorbers. The analytical model predicts that the available absorption peaks of the absorber are corresponding to the fundamental mode and only its odd harmonic modes of the standing wave. The model is in good agreement with numerical simulation and can explain the main features observed in typical ultrathin planar metamaterial absorbers. Based on this model, ultrathin planar metamaterial absorbers with multi-band absorptions at desired frequencies can be easily designed.


Assuntos
Simulação por Computador , Manufaturas , Modelos Teóricos , Óptica e Fotônica/métodos , Ar , Luz , Micro-Ondas , Fótons , Radiação Terahertz
12.
J Opt Soc Am A Opt Image Sci Vis ; 28(10): 2049-56, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21979509

RESUMO

Terahertz (THz) signals measured by means of the spectral-encoding technique with different temporal discrepancies between probe pulses and THz signals are investigated. It is found that imperfect synchronization between the chirped probe and THz pulses induce a distortion and this distortion affects significantly the retrieved THz spectrum if the temporal discrepancy is large. The distortion becomes more prominent if the probe pulse length is less than the optimal chirped probe pulse duration. A simple approach is proposed to realize the synchronization and minimize the distortion. THz signals from a high-voltage-biased air plasma filament are measured with this approach and distortion similar to the simulation results is observed.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(4 Pt 2): 046406, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18999542

RESUMO

Terahertz (THz) radiation from the interaction of ultrashort laser pulses with gases is studied both by theoretical analysis and particle-in-cell (PIC) simulations. A one-dimensional THz generation model based on the transient ionization electric current mechanism is given, which explains the results of one-dimensional PIC simulations. At the same time the relation between the final THz field and the initial transient ionization current is shown. One- and two-dimensional simulations show that for the THz generation the contribution of the electric current due to ionization is much larger than the one driven by the usual ponderomotive force. Ionization current generated by different laser pulses and gases is also studied numerically. Based on the numerical results we explain the scaling laws for THz emission observed in the recent experiments performed by Xie et al. [Phys. Rev. Lett. 96, 075005 (2006)]. We also study the effective parameter region for the carrier envelop phase measurement by the use of THz generation.

14.
Opt Express ; 16(16): 12342-9, 2008 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-18679511

RESUMO

A detailed analysis of the relationship between the duration of the chirped probe pulse and the bipolar terahertz (THz) pulse length in the spectral encoding technique is carried out. We prove that there is an optimal chirped probe pulse length (or an optimal chirp rate of the chirped probe pulse) matched to the input THz pulse length and derive a rigorous relationship between them. We find that only under this restricted condition the THz signal can be correctly retrieved.


Assuntos
Algoritmos , Desenho Assistido por Computador , Análise de Falha de Equipamento/métodos , Raios Infravermelhos , Lasers , Micro-Ondas , Modelos Teóricos , Processamento de Sinais Assistido por Computador/instrumentação , Transdutores , Simulação por Computador , Desenho de Equipamento
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(3 Pt 2): 036405, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17025752

RESUMO

Angular distribution of protons is measured from ethanol droplet spray irradiated by linearly polarized 150 fs laser pulses at an intensity of 1.1 x 10(16)W/cm2. Fast protons (with energies >16 keV ) with an anisotropic distribution can be observed only in or near the polarization plane of the laser fields, while the slow protons (with energies

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