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1.
Ultrasonics ; 141: 107338, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38723293

RESUMO

Recently, the moiré pattern has attracted lots of attention by superimposing two planar structures of regular geometries, such as two sets of metasurfaces or gratings. Here, we show the experimental investigation of acoustic moiré effect by using twisted bilayer gratings (i.e., one grating twisted with respect to the other). We observed the guided resonance that occurred when the incident ultrasound beam was coupled with the guiding modes in a meta-grating, significantly influencing the reflection and transmission. Tunable guided resonances from the moiré effect with complete ultrasound reflection at different frequencies were further demonstrated in experiments. Combining the measurements of transmission spectra and the Fast Fourier Transform analyses, we reveal the guided resonance frequencies of moiré ultrasonic metasurface can be effectively controlled by adjusting the twisting angle of the bilayer gratings. Our results can be explained in a simplified model based on the band folding theory, providing a reliable prediction on the precise control of ultrasound reflection via the twisting angle adjustment. Our work extends the moiré metasurface from optics into acoustics, which shows more possibilities for the ultrasound beam engineering from the moiré effect and enables the exploration of functional acoustic devices for ultrasound imaging, treatment and diagnosis.

2.
Plant Dis ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700470

RESUMO

Ficus hirta Vahl. is a Moraceae plant, named for its palm-like leaves. It is a widely used traditional medicinal material with definite curative effect. At the same time, it is also a commonly used soup material among the folk in South China. In March 2022, a serious leaf spot disease with symptoms similar to anthracnose was observed on F. hirta in several plantations in Qinzhou and Zhanjiang City of China, with an incidence of 32~65%. The early symptoms of infected leaves were small, round, yellow spots that further expanded into larger, brown, irregular, necrotic lesions surrounded by dark brown edges, which eventually led to leaf wilt. Twenty symptomatic leaves were collected from three plantations with a total area of about 10 hm2. Fragments (2×2 mm) from the 20 infected leaves were surface sterilized, plated on potato dextrose agar (PDA) and incubated at 28°C. After 3 days, isolates with similar cultural morphology were obtained and three representative isolates (WZMT-1, WZMT-3 and WZMT-8) were randomly selected for following study. The colonies by single-spore purification on PDA were initially cottony, pale white and became grayish green with age. The conidia were hyaline, abundant, cylindrical, with rounded ends, 14.4~18.2 µm×4.6~6.0 µm (av. 16.2 µm×5.4 µm, n=100). Conidiogenous cells hyaline, cylindrical or ampulliform, 6.2~22.7 µm × 2.7~5.0 µm (av. 12.9 µm×3.8 µm, n=50). Appressoria were brown to dark brown, ovoid to clavate, elliptical or irregular, 7.9~13.4 µm × 5.6~9.2 µm (av. 10.6 µm×7.9 µm, n=50). The morphology of the fungus resembled Colletotrichum fructicola (Prihastuti et al. 2009). For molecular identification, the internal transcribed spacer (ITS) regions, glyceraldehyde-3-phosphatedehydrogenase (GAPDH), actin (ACT), beta-tubulin 2 (TUB2), calmodulin (CAL), partial manganese superoxide dismutase (sod2), partial Apn2-Mat1-2 intergenic spacer and partial mating type (Mat1-2) (ApMat) genes were amplified from genomic DNA for the isolates using the primers described by Silva et al. (2012) and Weir et al. (2012). The sequences of the above seven loci of the three isolates (accession nos. OQ121661 to OQ121663 and OQ133400 to OQ133417) were obtained and showed over 99% identity with the existing sequences of ex-type culture ICMP 18581 of Colletotrichum fructicola (Weir et al. 2012). A multilocus phylogenetic analysis of the seven loci concatenated sequences using the maximum likelihood method revealed that the isolates belong to C. fructicola. To confirm pathogenicity, five 3-month-old potted plants were used for inoculation with each representative isolate. Tested plants were sprayed with 10 ml of a conidial suspension (1 × 108 conidia/ml) , and the controls plants were sprayed with sterile water. All the plants were incubated in a growth chamber at 26 ± 2°C with 95% relative humidity. After 10 days, typical lesions like those observed on the field plants appeared on all inoculated plants, while the control remained healthy. The same fungal pathogen was reisolated and the identity was confirmed by morphological characterization and molecular analysis, confirming Koch's postulates. The pathogen has been reported as the causal agent of anthracnose on a wide range of plant hosts worldwide (Marquez-Zequera et al. 2018; Horfer et al. 2021; Jiang et al. 2022; Li et al. 2023). To our knowledge, this is the first report of anthracnose on F. hirta caused by C. fructicola in southern China.

3.
Clin Chem ; 69(7): 763-770, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37207672

RESUMO

BACKGROUND: Deafness, autosomal recessive 16 (DFNB16) is caused by compound heterozygous or homozygous variants in STRC and is the second most common form of genetic hearing loss. Due to the nearly identical sequences of STRC and the pseudogene STRCP1, analysis of this region is challenging in clinical testing. METHODS: We developed a method that accurately identifies the copy number of STRC and STRCP1 using standard short-read genome sequencing. Then, we used whole genome sequencing (WGS) data to investigate the population distribution of STRC copy number in 6813 neonates and the correlation between STRC and STRCP1 copy number. RESULTS: The comparison of WGS results with multiplex ligation-dependent probe amplification demonstrated high sensitivity (100%; 95% CI, 97.5%-100%) and specificity (98.8%; 95% CI, 97.7%-99.5%) in detecting heterozygous deletion of STRC from short-read genome sequencing data. The population analysis revealed that 5.22% of the general population has STRC copy number changes, almost half of which (2.33%; 95% CI, 1.99%-2.72%) were clinically significant, including heterozygous and homozygous STRC deletions. There was a strong inverse correlation between STRC and STRCP1 copy number. CONCLUSIONS: We developed a novel and reliable method to determine STRC copy number based on standard short-read based WGS data. Incorporating this method into analytic pipelines would improve the clinical utility of WGS in the screening and diagnosis of hearing loss. Finally, we provide population-based evidence of pseudogene-mediated gene conversions between STRC and STRCP1.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva , Recém-Nascido , Humanos , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/genética , Perda Auditiva/diagnóstico , Perda Auditiva/genética , Sequência de Bases , Homozigoto , Variações do Número de Cópias de DNA , Peptídeos e Proteínas de Sinalização Intercelular/genética
4.
Reprod Toxicol ; 108: 35-42, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35093514

RESUMO

Inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis, are widespread in developed countries and gradually increasing in developing countries. Evidences showed that man with CD has a decrease of serum testosterone, but how IBD take effects on testicular testosterone synthesis is not well elucidated. To investigate the effects of IBD on testis, we analyzed testicular metabolome and transcriptome data of the dextran sulfate sodium (DSS) induced IBD mice. As a result, metabolomic data showed that DSS indeed induced androgen decrease in mouse testis. Correspondingly, androgen synthesis associated genes, especially Lhcgr, were down-regulated in DSS testis. From the metabolomic data, we found vitamin intake associated metabolites vitamin B2 and pyridoxamine were significantly decreased, whereas fatty acid metabolism associated molecules N-lauroylglycine and N-decanoylglycine were increased in DSS testis. In addition, we found 8-hydroxy-deoxyguanosine, a DNA oxidative damage marker, and 8-oxoguanine, a molecule responsible for DNA damage repair, were also changed in DSS testis. Simultaneously, our data also showed that DSS up-regulated the expression of meiosis initiation associated gene Stra8 and oxygen transport associated genes in testis. In summary, these results depicted the complex effects of colitis on testis. These metabolites and transcripts changed in DSS testis could be used as potential targets for IBD treatment or symptom relieve.


Assuntos
Colite/genética , Colite/metabolismo , Testículo/metabolismo , Animais , Colite/induzido quimicamente , Sulfato de Dextrana , Modelos Animais de Doenças , Masculino , Metaboloma , Camundongos Endogâmicos ICR , Transcriptoma
5.
Appl Opt ; 60(23): 6971-6977, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613180

RESUMO

Digital light processing (DLP) is currently a cutting-edge technology for desktop projection optical engines. Due to the passive luminescence characteristics, the DLP projection engine needs a few specific illumination optical components for light collimation, homogenization, and color combination, together with a projection lens matching the DLP chip and magnifying the image. In this paper, we propose a design approach that first splits the DLP projection optical engine into individual components for separate design, and then integrates them into a whole system for further verification. For the first step, the collimating lens group is designed for light collection, and the dichroic mirrors are used to fold the light path based on tri-color LED light sources. For the second step, a fly-eye lens and the corresponding relay lens group are designed to achieve uniform illumination on the DMD chip. The third step is to optimize the projection lens group for high-resolution projection display. Based on the design and simulation, the optical efficiency is 63.4% and the uniformity reaches 94.9% on the projection screen. The modulation transfer function (MTF) of the projection lens is higher than 0.4 at 66 lines for the distance of 500∼1500mm, and the distortion is lower than 1%. Simulation results show that the total luminous flux is estimated to reach 224.15 lm when the powers of tri-color LEDs are 21 W, 15.5 W, and 25 W, respectively. A projector prototype is built and tested for further verification, which provides a luminous flux of 220.43 lm and uniformity of 90.22%, respectively. The proposed design, demonstrated by both simulation and experiment, exhibits high feasibility and application potential in state-of-the-art commercial projector design.

6.
Stem Cells Int ; 2021: 6633111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854551

RESUMO

OBJECTIVES: Urinary stem cells (USCs) have the capacity for unlimited growth and are promising tools for the investigations of cell differentiation and urinary regeneration. However, the limited life span significantly restricts their usefulness. This study is aimed at exploring the effect of integrin-linked kinase (ILK) on the smooth muscle cells (SMCs) differentiation of the dog USCs and investigating its molecular mechanism. METHODS: An immortalized USCs cell line with the molecular markers and biological functions was prepared. After successfully inducing the differentiation of USCs into SMCs, the expression level of the unique key factor and its mechanisms in this process was determined through real-time polymerase chain reaction, Western blot, or Immunofluorescence staining. RESULTS: We found that high cell density promoted USCs differentiation SMCs, and ILK was necessary for USCs differentiation into SMCs. Knocking down ILK decreased the expression of SMCs specific-marker, while using a selective ILK agonist increased the expression of SMCs specific-marker. Furthermore, ILK regulated SMCs differentiation in part through the activation of NF-κB pathway in USCs. A NF-κB activity assay showed overexpression of ILK could significantly upregulate NF-κB p50 expression, and NF-κB p50 acts as downstream signal molecular of ILK. CONCLUSION: High cell density induces the differentiation of USCs into SMCs, and ILK is a key regulator of myogenesis. Furthermore, NF-κB signaling pathway might play a crucial role in this process.

7.
J Assist Reprod Genet ; 38(6): 1373-1385, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33914207

RESUMO

Insufficiency of oocyte activation impairs the subsequent embryo development in assisted reproductive technology (ART). Intracellular Ca2+ concentration ([Ca2+]i) oscillations switch the oocytes to resume the second meiosis and initiate embryonic development. However, the [Ca2+]i oscillation patterns in oocytes are poorly characterized. In this study, we investigated the effects of various factors, such as the oocytes age, pH, cumulus cells, in vitro or in vivo maturation, and ER stress on [Ca2+]i oscillation patterns and pronuclear formation after parthenogenetic activation of mouse oocytes. Our results showed that the oocytes released to the oviduct at 17 h post-human chorionic gonadotrophin (hCG) displayed a significantly stronger [Ca2+]i oscillation, including higher frequency, shorter cycle, and higher peak, compared with oocytes collected at earlier or later time points. [Ca2+]i oscillations in acidic conditions (pH 6.4 and 6.6) were significantly weaker than those in neutral and mildly alkaline conditions (pH from 6.8 to 7.6). In vitro-matured oocytes showed reduced frequency and peak of [Ca2+]i oscillations compared with those matured in vivo. In vitro-matured oocytes from the cumulus-oocyte complexes (COCs) showed a significantly higher frequency, shorter cycle, and higher peak compared with the denuded oocytes (DOs). Finally, endoplasmic reticulum stress (ER stress) severely affected the parameters of [Ca2+]i oscillations, including elongated cycles and lower frequency. The pronuclear (PN) rate of oocytes after parthenogenetic activation was correlated with [Ca2+]i oscillation pattern, decreasing with oocyte aging, cumulus removal, acidic pH, and increasing ER stress. These results provide fundamental but critical information for the mechanism of how these factors affect oocyte activation.


Assuntos
Desenvolvimento Embrionário/genética , Estresse do Retículo Endoplasmático/genética , Técnicas de Maturação in Vitro de Oócitos , Oócitos/crescimento & desenvolvimento , Animais , Gonadotropina Coriônica/genética , Células do Cúmulo/metabolismo , Feminino , Meiose/genética , Camundongos , Partenogênese/genética , Gravidez
8.
Zhonghua Nan Ke Xue ; 24(4): 327-330, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30168952

RESUMO

OBJECTIVE: To investigate the association of circumcision with the incidence of human papillomavirus (HPV) infection in men. METHODS: We collected the samples from the surface of the coronal sulcus, glans penis, penile shaft and scrotum of 351 males examined for HPV infection in our hospital from January 2016 to August 2017, of whom 118 had received circumcision while the other 233 had not. We compared the incidence rate of HPV infection between the circumcision and non-circumcision groups and analyzed the association of the age of circumcision with the incidence of HPV infection. RESULTS: HPV infection was found in 135 (38.46%) of the males, 29 (24.58%) in the circumcision group and 106 (45.49%) in the non-circumcision group, significantly lower in the former than in the latter (χ² = 14.48, P < 0.01). The incidence rate of HPV infection was also remarkably lower in the males circumcised at ≤17 years (13.16% ï¼»5/38ï¼½) than in those circumcised at >17 years of age (30.0% ï¼»24/80ï¼½) (χ² = 3.942, P = 0.047). CONCLUSIONS: Male circumcision helps reduce the incidence rate of HPV infection in men and earlier surgery may achieve even better effect.


Assuntos
Circuncisão Masculina/estatística & dados numéricos , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Pênis/virologia , Escroto/virologia , Humanos , Incidência , Masculino , Infecções por Papillomavirus/diagnóstico
9.
Zhonghua Nan Ke Xue ; 24(6): 520-524, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-30173457

RESUMO

OBJECTIVE: To study the clinical application value of the penile erectile strength measurement (PESM) band in the differentiation of psychogenic from organic erectile dysfunction (ED). METHODS: Eighty ED patients unable to achieve or maintain adequate penile erection to complete sexual intercourse were included in the experimental group and another 40 healthy subjects with normal erectile function enrolled as controls. The ED cases were classified into mild, moderate and severe ED according to the IIEF-5 scores and divided into psychogenic and organic ED based on the results of the nocturnal penile tumescence (NPT) test. Then all the subjects underwent a three-night continuous monitoring with the PESM band and, according to the band fracture rate, the ED cases were also classified into psychogenic and organic ED. The rates of missed diagnosis, misdiagnosis and diagnostic coincidence of PESM were calculated with the results of NPT as the standard for differentiating psychogenic from organic ED. RESULTS: The results of NPT tests revealed 51 cases of psychogenic and 29 cases of organic ED in the experimental group. The band fracture rate in PESM was 95.0% in the mild, 80.9% in the moderate and 52.8% in the severe ED patients. Of the 51 cases of psychogenic ED detected by NPT test, 43 were diagnosed as psychogenic and the other 8 as organic ED with the PESM band, with a coincidence rate of 84.3%. Of the 29 cases of organic ED revealed by NPT test, 5 were diagnosed as psychogenic and the other 24 as organic ED by PESM, with a coincidence rate of 82.8%. Normal erectile function with three-level fracture of the band was observed in the PESM of the normal controls, which showed a coincidence rate of 100% with the results of NPT tests. Based on the standard of the NPT test, the rates of missed diagnosis, misdiagnosis and diagnostic coincidence of the PESM band in differentiating psychogenic from organic ED were 15.7%, 17.2%, and 83.8%, respectively, with a Kappa value of 0.656 (P <0.05). CONCLUSIONS: The penile erectile strength measurement band can be used as a screening tool for initial differentiation of psychogenic from organic ED.


Assuntos
Disfunção Erétil/classificação , Disfunção Erétil/fisiopatologia , Ereção Peniana/fisiologia , Estudos de Casos e Controles , Coito , Erros de Diagnóstico/estatística & dados numéricos , Disfunção Erétil/diagnóstico , Disfunção Erétil/psicologia , Humanos , Masculino
10.
Zhonghua Nan Ke Xue ; 23(9): 808-812, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29726662

RESUMO

OBJECTIVE: To investigate the values of serum calculated free testosterone (cFT), testosterone secretion index (TSI), and free testosterone index (FTI) in the diagnosis of ED with androgen deficiency by observing their changes in the patient. METHODS: We conducted this study among 185 men complaining of ED and 35 20-40 years old healthy males presenting at the clinic for premarital medical checkup. We asked them about their medical history, to fill in the International Index of Erectile Function (IIEF-5) Questionnaire, and to complete the nocturnal penile tumescence (NPT) test. According to the data obtained, 150 of the complainants were diagnosed as ED patients and 25 of the healthy examinees were included in the control group. We determined the levels of total serum testosterone (TT), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), serum albumin (ALB), cFT, bio-available testosterone (bio-T), TSI, and FTI in the two groups of subjects. Using cFT ≤0.3 nmol/L, TSI ≤2.8, and FTI ≤0.4 as the critical values and TT ≤11.5 nmol/L as the gold standard for androgen deficiency, we calculated cFT-, TSI-, and FTI-related rates of missed diagnosis, misdiagnosis, and diagnostic coincidence. RESULTS: With TT ≤11.5 nmol/L as the criterion, the cFT-, TSI-, and FTI-related rates of coincidence in the diagnosis of androgen deficiency in the ED patients were 90.8%, 85.8%, and 80.8%, those of missed diagnosis were 4.0%, 33.3%, and 44.0%, and those of misdiagnosis were 10.5%, 19.4%, and 12.6%, with the Kappa of values 0.755, 0.564, and 0.427, respectively (P <0.05). The levels of serum TT, cFT, Bio-T, TSI, and FTI were decreased with increased age of the 20-40 years old ED patients, with statistically significant differences among different age groups except the serum TT level. However, no statistically significant differences were found in the levels of TT, cFT, Bio-T, TSI, and FTI among the patients with different IIEF-5 scores. CONCLUSIONS: The level of cFT has a higher value than those of TT, TSI, and TSI in the diagnosis of ED with androgen deficiency in 20-40 years old men.


Assuntos
Disfunção Erétil/sangue , Disfunção Erétil/diagnóstico , Testosterona/sangue , Adulto , Androgênios/deficiência , Estudos de Casos e Controles , Humanos , Hormônio Luteinizante/sangue , Masculino , Albumina Sérica/análise , Globulina de Ligação a Hormônio Sexual/análise , Adulto Jovem
11.
Ultrasonics ; 44 Suppl 1: e693-7, 2006 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-16831453

RESUMO

This paper reports a new type miniature-conical transducer for acoustic emission measurements. The transducer follows the basic idea and structure of a conventional NBS conical transducer, but is much compact in size and easier to use. The improvements are made possible by introducing an excimer laser micromachining method for fabricating smaller PZT conical elements, which play a key role in the transducer. Conical PZT elements with contact size less then 300 microm are laser-machined and the miniature-conical transducers are constructed. Standard quantitative acoustic emission testing is performed on a plate using the fabricated transducers and good results are observed. The transducers can be very useful in many applications involving quantitative measurements of transient elastic waves.

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