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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(1): 103-106, 2024 Jan 15.
Artículo en Zh | MEDLINE | ID: mdl-38269468

RESUMEN

A male infant, aged 6 days, was admitted to the hospital due to respiratory distress and systemic desquamative rash after birth. The infant presented with erythema and desquamative rash, respiratory failure, recurrent infections, chronic diarrhea, hypernatremic dehydration, and growth retardation. Comprehensive treatment, including anti-infection therapy, intravenous immunoglobulin administration, and skin care, resulted in improvement of the rash, but recurrent infections persisted. Second-generation sequencing revealed a homozygous mutation in the SPINK5 gene, consistent with the pathogenic variation of Netherton syndrome. The family opted for palliative care, and the infant died at the age of 2 months after discharge. This report documents a case of Netherton syndrome caused by the SPINK5 gene mutation in the neonatal period, and highlights multidisciplinary diagnosis and therapy for this condition.


Asunto(s)
Exantema , Síndrome de Netherton , Lactante , Recién Nacido , Humanos , Masculino , Síndrome de Netherton/diagnóstico , Síndrome de Netherton/genética , Reinfección , Disnea , Homocigoto
2.
Paediatr Perinat Epidemiol ; 36(3): 380-389, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34467552

RESUMEN

BACKGROUND: Retinopathy of prematurity (ROP) continues to be a major cause of visual impairment and blindness in premature infants and children. OBJECTIVES: To investigate the incidence of severe ROP receiving treatment in extremely preterm (EP) infants in China over time. The risk factors for ROP treatment were also assessed. METHODS: This was a multicentre retrospective study and a subanalysis of baseline data from the "Outcomes of EP infants in China 2010-2019" study. This study was conducted in 68 tertiary neonatal care centres from 31 provinces of China. Infants with a gestational age of 230 -276  weeks and admitted to a neonatal unit within the first 72 h of life between 2010 and 2019 were enrolled. Incidence of ROP was analysed in infants who survived to 32 weeks postmenstrual age and screened for ROP. Multivariable modified Poisson regression models were used to identify risk factors for ROP treatment. RESULTS: Among 7295 eligible infants, 4701 (64.5%) survived to 32 weeks postmenstrual age and met ROP screening criteria. Of the 3756 infants who screened and with ROP data, 2320 (61.8%) developed ROP of any stage. The overall incidence of ROP treatment was 12.6%, decreasing from 45.5% at 23 weeks to 8.3% at 27 weeks. During the 10-year period, the incidence of ROP treatment did not change, although the incidence of any ROP increased over time. Independent risk factors associated with ROP treatment included lower gestational age, small for gestational age, multiple birth, severe intraventricular haemorrhage, patent ductus arteriosus and supplemental oxygen duration. CONCLUSIONS: The incidence of EP infants receiving ROP treatment showed no change during this 10-year period in China. Prevention of prematurity and foetal growth restriction, judicious use of oxygen and reducing comorbidities are promising factors that may reduce the incidence of ROP needing treatment in these high-risk infants.


Asunto(s)
Retinopatía de la Prematuridad , Peso al Nacer , Niño , Edad Gestacional , Humanos , Incidencia , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Oxígeno , Retinopatía de la Prematuridad/epidemiología , Retinopatía de la Prematuridad/terapia , Estudios Retrospectivos , Factores de Riesgo
3.
Opt Express ; 29(4): 6248-6256, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726150

RESUMEN

The dual-frequency laser interferometer is an indispensable instrument to measure length, position, deformation and other parameters with high precision and long measurement distance in the advanced manufacturing industry and scientific research. In general, the light source of interferometer is the dual-frequency He-Ne laser. The disadvantages of He-Ne laser include generally large size, more heat radiation to the environment, and limited service life, which limits its application. In this paper, we study a microchip Nd:YAG dual-frequency laser interferometer with a 17.4 MHz frequency difference, which is formed by the stress-induced birefringence in the microchip itself. The down-conversion mixer is designed to decrease the beat frequency to about 5 MHz in heterodyne signal preprocessing modular to meet the bandwidth of phase meter. The experimental results show that the microchip Nd:YAG dual-frequency laser interferometer has a displacement resolution of 10 nm and a measuring range of 500 mm. Due to the advantages of the microchip dual-frequency laser, such as small size (40×40×35 mm), good portability, less power consumption and almost infinite service life, the microchip Nd:YAG dual-frequency laser interferometer has broad application prospects.

4.
Opt Lett ; 44(22): 5414-5417, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31730071

RESUMEN

A novel method of ultrasound-modulated optical tomography (UOT) detection based on the laser feedback technology is proposed in this Letter. The system has advantages such as a simple structure, high sensitivity, and reflective configuration. Effective penetration depths of up to 9 cm and 5 cm in phantom and biological tissues, respectively, have been demonstrated experimentally. The detection capability is comparable with the state of the art in the transmission mode but with a much lower photon consumption. Although a lot remains to be improved, the proposed method is promising for further development toward practical applications.

5.
Opt Lett ; 43(6): 1207-1210, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29543252

RESUMEN

Ultrasound modulated laser confocal feedback technology is proposed in the imaging inside turbid media. By selecting the detectable signal photons and rejecting the background noise photons in the frequency domain based on the ultrasound modulation, the signal-to-noise ratio (SNR) can be much improved, especially in the turbid media, compared with the traditional imaging without ultrasound modulation. This is a promising method to reach both a larger penetration depth and a better SNR than other optical methods.

6.
Appl Opt ; 57(20): 5823-5830, 2018 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-30118053

RESUMEN

The depth of focus extension in optical imaging is of considerable interest. In this paper, a laser frequency-shifted feedback scanning imaging configuration is demonstrated whose depth of focus is greatly extended through numerical filtering. The transmission characteristics of the system are studied. The original image is acquired through a two-dimensional scanning point by point with the target placed on a defocused plane. Filtered in the frequency domain, images on any oriented plane can be refocused. The superior performances are presented by imaging a three-dimensional target, and the process of gradual refocusing is demonstrated. To obtain the maximum extension in the depth of defocus, a series of numerical experiments has been carried out, which reveals its depth of focus is capable of being extended to four times the length of the objective focus length. The fabulous performances can motivate three-dimensional surface profile measurement.

7.
Opt Express ; 24(23): 26558-26564, 2016 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-27857388

RESUMEN

A fiber heterodyne self-mixing interferometer with orthogonally polarized light compensation is achieved. This system can adapt to various complex scenes while still keeping ultra-high sensitivity and anti-disturbance capability. Ultra-high sensitivity microchip laser is used as the laser source and polarization maintaining(PM) fiber makes the light path easy to accommodate to complex spaces, such as remote or narrow and small space. Besides, orthogonally polarized light inside PM fiber can eliminate the measurement error on account of environment disturbance. At present, the displacement resolution could be less than 10nm, which shows a great potential in nano-metrology.

8.
Opt Lett ; 41(20): 4827-4830, 2016 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28005841

RESUMEN

A heterodyne Nd:YVO4 microchip laser self-mixing interferometry based on frequency and polarization multiplexing has been demonstrated. By using two orthogonally polarized lights to measure the measurement and reference target, the effect of the acousto-optic crystal thermal creep and air disturbance in interference light path is eliminated. In addition, the measurement error caused by the difference between two identical microchip lasers is compensated for by shifted frequency multiplexing technique. A rate equations model with multi-channel frequency-shifted feedback is established for interpreting the principle of the interferometry. Due to the ultrahigh sensitivity of the microchip laser, the target used in the experiment is a non-cooperative object which is different from the targets in conventional Michelson interferometers. Under typical room conditions, the short-term resolution is better than 2.5 nm, and the long-term zero drift is less than 60 nm within 7 h. The result shows that this self-mixing interferometry system is feasible and robust in the field of displacement measurement.

9.
Opt Lett ; 41(4): 844-6, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26872203

RESUMEN

A self-mixing interferometry with mutual independent orthogonal polarized light is introduced. Its most important feature is that two mutual independent orthogonal lights are used as measuring and reference light. Frequency shifting and polarization multiplexing technologies are used in the proposed optical system. Phase variation of the two orthogonal polarized beams is simultaneously measured through heterodyne demodulation with a lock-in amplifier. The phase difference of the orthogonal polarized light accurately reflects the target displacement. The target in this system is a non-cooperative object which is different from a traditional Michelson interferometer. The primary experimental results show that this kind of self-mixing interferometry is very feasible. Under typical room conditions, the system's short-term resolution is better than 2 nm.

10.
Appl Opt ; 55(11): 2858-62, 2016 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-27139847

RESUMEN

The pump polarization direction can greatly influence the characteristics of the laser diode end-pumped monolithic microchip Nd:YAG dual-frequency laser. We experimentally observe the lasing thresholds and the optical powers of two splitting modes versus the pump polarization direction. The effect of the pump-induced gain anisotropy on the mode oscillation sequence is analyzed. And the effect on the intensities of these modes is also proved with a rate equation model. This study contributes to the improvement of the stability and the reliability of the Nd:YAG dual-frequency laser.

11.
Fetal Pediatr Pathol ; 35(3): 173-85, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27003382

RESUMEN

BACKGROUND: The inhibitory effects of pigment epithelium-derived factor (PEDF) on retinal neovascularization were observed in a murine model of oxygen-induced retinopathy. METHODS: PEDF was administered via intravitreal injection into the right eye of mice subjected to hyperoxia. The proliferative neovascular response was assessed by evaluating the vascular pattern in retinal flat-mounts and quantified by counting the number of new vascular cell nuclei extending into the internal limiting membrane. Retinas were stained for vascular endothelial growth factor (VEGF), PEDF, and CD31 with immunohistochemical method. RESULTS: The effect of PEDF on retinal neovascularization is related to the postnatal age at the time of injection and the number of injections. The injection of 2 µg of PEDF at postnatal day 12 (P12) and P14 markedly inhibited retinal neovascularization. CONCLUSION: Locally administered PEDF is a potentially effective vascular inhibitory factor for the treatment and prevention of retinopathy of prematurity.


Asunto(s)
Proteínas del Ojo/metabolismo , Hiperoxia , Factores de Crecimiento Nervioso/metabolismo , Oxígeno/metabolismo , Neovascularización Retiniana/metabolismo , Neovascularización Retiniana/patología , Serpinas/metabolismo , Animales , Modelos Animales de Enfermedad , Hiperoxia/metabolismo , Inmunohistoquímica/métodos , Ratones Endogámicos C57BL
12.
Opt Express ; 23(13): 16977-83, 2015 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-26191707

RESUMEN

A simple and high-accuracy self-mixing interferometer based on single high-order orthogonally polarized feedback effects is presented. The single high-order feedback effect is realized when dual-frequency laser reflects numerous times in a Fabry-Perot cavity and then goes back to the laser resonator along the same route. In this case, two orthogonally polarized feedback fringes with nanoscale resolution are obtained. This self-mixing interferometer has the advantages of higher sensitivity to weak signal than that of conventional interferometer. In addition, two orthogonally polarized fringes are useful for discriminating the moving direction of measured object. The experiment of measuring 2.5nm step is conducted, which shows a great potential in nanometrology.

13.
Opt Lett ; 40(15): 3615-8, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26258371

RESUMEN

We present a novel method using Nd:YVO4 laser with a waveplate in the external cavity to generate two orthogonally polarized signals with stable and adjustable phase difference. The phase difference is observed in the presence of external interference, and it is determined by the phase retardation of the waveplate. A model based on birefringent external-interference effect is proposed to theoretically explain the phase difference phenomenon, and the arithmetic solution of the relation between the phase difference and the phase retardation of waveplate is given. The simulated results accord with the experimental phenomena. This Letter provides the possibility for the measurement of phase retardation and also offers guidance to the design of interferometers based on fringe counting technique.

14.
Appl Opt ; 54(2): 204-9, 2015 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-25967618

RESUMEN

We present a measurement method for optical phase retardation, which utilizes a phase-difference phenomenon of the feedback fringes in orthogonally polarized directions of a laser with anisotropic weak feedback. This phase difference is dominated by the measured retardation. The measurement principles are given based on the 3-mirror cavity model, and experiments are conducted with quartz waveplates (WPs). A measurement range 0°-180° is achieved, the uncertainty is theoretically better than 0.5°, and the measurement precision can be improved further. This method does not require researchers to know beforehand the principal axes directions of the WPs, and has better anti-disturbance ability than the previous method based on laser feedback.

15.
Am J Perinatol ; 32(4): 363-70, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25217737

RESUMEN

BACKGROUND: Human toll-like receptor 4 (TLR4) is an important receptor in innate immunity, particularly against gram-negative bacterial infection (GNBI). In our study, we evaluated associations of TLR4 single nucleotide polymorphisms (SNPs) with GNBI in Han Chinese neonates. PATIENTS AND METHODS: Polymorphisms in TLR4 were genotyped in 201 neonates with GNBI and 279 gestational age and birth weight-matched controls without GNBI. Polymorphism analyses were applied to allele frequencies of the detected TLR4 SNPs and their associations with various clinical entities, including premature birth and GNBI were assessed. RESULTS: A total of six SNPs with more than 5% frequency were found in several promoter sequences, including rs10759931, rs2737190, rs10116253, rs10983755, rs1927914, and rs10759932. Mutation allele frequencies ranged from 23 to 41%. There were no SNPs with a frequency greater than 5% in exon analyses. Allele G rs2737190 mutations and GGCGGC haplotypes were more frequent among preterm GNBI neonates (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.02-1.71 and OR, 1.89; 95% CI, 1.19-3.00, respectively). No specific alleles or haplotypes were associated with GNBI status among term neonates. CONCLUSION: In this study population of Han Chinese, there was a significant association between an ethnical unique SNP in the TLR4 promoter region and preterm neonatal GNBIs.


Asunto(s)
Infecciones por Bacterias Gramnegativas/genética , Polimorfismo de Nucleótido Simple , Receptor Toll-Like 4/genética , Alelos , Pueblo Asiatico , China , Femenino , Frecuencia de los Genes , Infecciones por Bacterias Gramnegativas/etnología , Haplotipos , Humanos , Recién Nacido , Masculino , Mutación , Oportunidad Relativa
16.
Artículo en Inglés | MEDLINE | ID: mdl-38700973

RESUMEN

Prostate cancer screening often relies on cost-intensive MRIs and invasive needle biopsies. Transrectal ultrasound imaging, as a more affordable and non-invasive alternative, faces the challenge of high inter-class similarity and intra-class variability between benign and malignant prostate cancers. This complexity requires more stringent differentiation of subtle features for accurate auxiliary diagnosis. In response, we introduce the novel Deep Augmented Metric Learning (DAML) network, specifically tailored for ultrasound-based prostate cancer classification. The DAML network represents a significant innovation in the metric learning space, introducing the Semantic Differences Mining Strategy (SDMS) to effectively discern and represent subtle differences in prostate ultrasound images, thereby enhancing tumor classification accuracy. Additionally, the DAML network strategically addresses class variability and limited sample sizes by combining the Linear Interpolation Augmentation Strategy (LIAS) and Permutation-Aided Reconstruction Loss (PARL). This approach enriches feature representation and introduces variability with straightforward structures, mirroring the efficacy of advanced sample generation techniques. We carried out comprehensive empirical assessments of the DAML model by testing its key components against a range of models, ensuring its effectiveness. Our results demonstrate the enhanced performance of the DAML model, achieving classification accuracies of 0.857 and 0.888 for benign and malignant cancers, respectively, underscoring its effectiveness in prostate cancer classification via medical imaging.

17.
J Hazard Mater ; 465: 133404, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38218037

RESUMEN

Organophosphate flame retardants (OPFRs) pose a new challenge to the marine environment due to their toxicity and persistence. This study explores the contributions of OPFR emissions from different land sources and sectors to its contamination of the East China Sea (ECS) using a novel atmospheric transport model(ChnMETOP)for POPs and a marine food web model. The results show that the major land sources causing OPFR pollution in the ECS were situated in Yangtze River Delta (YRD) and middle reach areas of China's Yangtze River, confirming that source proximity made most significant contributions to OPFR pollution in the ECS. Among those OPFR emission sectors, industrial emissions accounted for the highest modeled OPFR levels in the seawaters, followed by the OPFR usage process in textile, plastic, and rubber products. Assessment of bioaccumulation of OPFR in the marine food web of the ECS and the potential risk in commercial fish consumers reveals lower exposure risk via dietary fish ingestion. However, the risk might increase if OPFRs are continuously bioaccumulated in the biotic and released into the abiotic marine environment. This study simultaneously identified both the source locations and emission sectors, thereby providing important policy implications in mitigating OPFR pollution in the ECS marine environment.


Asunto(s)
Retardadores de Llama , Contaminantes Químicos del Agua , Animales , Compuestos Organofosforados , Contaminantes Químicos del Agua/análisis , Organofosfatos , China
18.
Opt Express ; 21(11): 13684-90, 2013 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-23736621

RESUMEN

The effect of intra-cavity phase anisotropy on polarization flipping induced by optical feedback is experimentally and theoretically investigated. In experiments, we place a polarizer in feedback cavity to induce polarization flipping. The polarization flipping doesn't occur when the angle between polarizer axis and laser polarization approaches 45°. It is found that the larger the phase anisotropy is, the more easily the polarization flipping happens. As the intra-cavity phase anisotropy is increased, polarization flipping always occurs when the angle between polarizer axis and laser polarization is changed from 0° to 90°. This indicates that the phase anisotropy of the laser cavity contributes to the polarization flipping. It is necessary to keep certain phase anisotropy for the lasers used for polarization control.

19.
Opt Express ; 21(8): 10019-24, 2013 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-23609707

RESUMEN

A novel laser feedback interferometry based on high-order feedback is presented and realized for the first time. The interferometer uses a birefringence dual frequency laser and a tilted feedback mirror with high amplitude reflectivity to generate high density cosine-like optical fringes. These optical fringes have nanoscale resolution. Particularly, phase quasi-quadrature between the dual frequency fringes is obtained because of the phase shift caused by the changes of external optical path length. This phase characteristic can be used to distinguish the direction of movement easily. Under typical room conditions, the system's resolution is 0.51nm in 850µm range, and its 2 min displacement accuracy is 5nm.


Asunto(s)
Interferometría/instrumentación , Rayos Láser , Lentes , Refractometría/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Retroalimentación
20.
Opt Express ; 21(7): 8044-50, 2013 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-23571894

RESUMEN

An instrument for angle measurement based on laser feedback has been designed. The measurement technique is based on the principle that when a wave plate placed into a feedback cavity rotates, its phase retardation varies. Phase retardation is a function of the rotating angle of the wave plate. Hence, the angle can be converted to phase retardation. The phase retardation is measured at certain characteristic points identified in the laser outputting curve that are then modulated by laser feedback. The angle of a rotating object can be measured if it is connected to the wave plate. The main advantages of this instrument are: high resolution, compact, flexible, low cost, effective power, and fast response.


Asunto(s)
Artrometría Articular/instrumentación , Rayos Láser , Refractometría/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Retroalimentación
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