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1.
Ann Hematol ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38736014

RESUMO

There has been no severity evaluation model for pediatric patients with hemophagocytic lymphohistiocytosis (HLH) that uses readily available parameters. This study aimed to develop a novel model for predicting the early mortality risk in pediatric patients with HLH using easily obtained parameters whatever etiologic subtype. Patients from one center were divided into training and validation sets for model derivation. The developed model was validated using an independent validation cohort from the second center. The prediction model with nomogram was developed based on logistic regression. The model performance underwent internal and external evaluation and validation using the area under the receiver operating characteristic curve (AUC), calibration curve with 1000 bootstrap resampling, and decision curve analysis (DCA). Model performance was compared with the most prevalent severity evaluation scores, including the PELOD-2, P-MODS, and pSOFA scores. The prediction model included nine variables: glutamic-pyruvic transaminase, albumin, globulin, myohemoglobin, creatine kinase, serum potassium, procalcitonin, serum ferritin, and interval between onset and diagnosis. The AUC of the model for predicting the 28-day mortality was 0.933 and 0.932 in the training and validation sets, respectively. The AUC values of the HScore, PELOD-2, P-MODS and pSOFA were 0.815, 0.745, 0.659 and 0.788, respectively. The DCA of the 28-day mortality prediction exhibited a greater net benefit than the HScore, PELOD-2, P-MODS and pSOFA. Subgroup analyses demonstrated good model performance across HLH subtypes. The novel mortality prediction model in this study can contribute to the rapid assessment of early mortality risk after diagnosis with readily available parameters.

2.
J Clin Immunol ; 43(5): 989-998, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36877313

RESUMO

PURPOSE: The first step in diagnosing hemophagocytic lymphohistiocytosis (HLH) is to suspect its presence and then order the appropriate diagnostic tests. The development of screening procedures for HLH could facilitate early diagnosis. In this study, we evaluated the utility of fever, splenomegaly, and cytopenias as screening criteria for identifying pediatric HLH at an early stage, built a screening model using commonly measured laboratory parameters, and developed a step-wise screening procedure for pediatric HLH. METHODS: The medical records of 83,965 pediatric inpatients, including 160 patients with HLH, were collected retrospectively. The utility of fever, splenomegaly, hemoglobin level, and platelet and neutrophil counts at hospital admission as screening criteria for HLH was evaluated. For HLH patients who might be missed by screening based on the presence of fever, splenomegaly, and cytopenias, a screening model using common laboratory parameters was developed. Following that, a three-step screening procedure was then developed. RESULTS: The criteria of cytopenias affecting two or more lineages plus fever or splenomegaly had a sensitivity of 51.9% and a specificity of 98.4% for identifying HLH in pediatric inpatients. Our screening score model comprises six parameters: splenomegaly, platelet count, neutrophil count, albumin level, total bile acid level, and lactate dehydrogenase level. The use of the validation set had a sensitivity of 87.0% and a specificity of 90.6%. A three-step screening procedure has been developed: Step 1: Is fever or splenomegaly present? (Yes: risk for HLH should be considered, go to Step 2; No: less likely HLH); Step 2: Are cytopenias affecting at least two lineages? (Yes: consider HLH; No: go to Step 3); Step 3: Calculate the screening score. Is the sum of the score greater than 37? (Yes: consider HLH; No: less likely HLH). The overall sensitivity and specificity of the three-step screening procedure were 91.9% and 94.4%, respectively. CONCLUSION: A significant proportion of pediatric HLH patients present at the hospital without having all three symptoms: fever, splenomegaly, and cytopenias. Our three-step screening procedure, utilizing commonly available clinical and laboratory parameters, can effectively identify pediatric patients who may be at high risk for HLH.


Assuntos
Anemia , Leucopenia , Linfo-Histiocitose Hemofagocítica , Trombocitopenia , Humanos , Criança , Linfo-Histiocitose Hemofagocítica/diagnóstico , Esplenomegalia/diagnóstico , Estudos Retrospectivos , Febre/diagnóstico , Febre/etiologia
3.
J Clin Immunol ; 43(8): 1997-2010, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37653176

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome characterized by excessive activation of the immune system, along with uncontrolled proliferation of activated macrophages and lymphocytes. The clinical features of HLH often overlap with the clinical features of other severe inflammatory conditions such as sepsis, hindering accurate and timely diagnosis. In this study, we performed a data-independent acquisition mass spectrometry-based plasma proteomic analysis of 33 pediatric patients with HLH compared with four control groups: 39 healthy children, 43 children with sepsis, 39 children hospitalized in the pediatric intensive care unit without confirmed infections, and 21 children with acute Epstein-Barr virus infection. Proteomic comparisons between the HLH group and each of the control groups showed that HLH was characterized by alterations in complement and coagulation cascades, neutrophil extracellular trap formation, and platelet activation pathways. We identified eight differentially expressed proteins in patients with HLH, including plastin-2 (LCP1), vascular cell adhesion protein 1, fibrinogen beta chain, fibrinogen gamma chain, serum amyloid A-4 protein, extracellular matrix protein 1, apolipoprotein A-I, and albumin. LCP1 emerged as a candidate diagnostic marker for HLH with an area under the curve (AUC) of 0.97 in the original cohort and an AUC of 0.90 (sensitivity = 0.83 and specificity = 1.0) in the validation cohort. Complement C1q subcomponent subunit B was associated with disease severity in patients with HLH. Based on comparisons with multiple control groups, this study provides a proteomic profile and candidate biomarkers of HLH, offering researchers novel information to improve the understanding of this condition.


Assuntos
Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Sepse , Humanos , Criança , Linfo-Histiocitose Hemofagocítica/diagnóstico , Infecções por Vírus Epstein-Barr/diagnóstico , Estado Terminal , Proteômica , Herpesvirus Humano 4 , Sepse/diagnóstico , Biomarcadores , Fator B do Complemento , Fibrinogênio
4.
Nanotechnology ; 34(24)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36881863

RESUMO

Low-dimensional tin selenide nanoribbons (SnSe NRs) show a wide range of applications in optoelectronics fields such as optical switches, photodetectors, and photovoltaic devices due to the suitable band gap, strong light-matter interaction, and high carrier mobility. However, it is still challenging to grow high-quality SnSe NRs for high-performance photodetectors so far. In this work, we successfully synthesized high-quality p-type SnSe NRs by chemical vapor deposition and then fabricated near-infrared photodetectors. The SnSe NR photodetectors show a high responsivity of 376.71 A W-1, external quantum efficiency of 5.65 × 104%, and detectivity of 8.66 × 1011Jones. In addition, the devices show a fast response time with rise and fall time of up to 43µs and 57µs, respectively. Furthermore, the spatially resolved scanning photocurrent mapping shows very strong photocurrent at the metal-semiconductor contact regions, as well as fast generation-recombination photocurrent signals. This work demonstrated that p-type SnSe NRs are promising material candidates for broad-spectrum and fast-response optoelectronic devices.

5.
Nutr Metab Cardiovasc Dis ; 33(3): 541-550, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646604

RESUMO

BACKGROUND AND AIMS: Elevated urinary albumin-creatinine ratio (ACR) is an established risk factor for lower extremity peripheral arterial disease (PAD) in non-diabetes individual. This study aimed to determine the relationship between urinary ACR level and PAD in diabetes population. METHODS AND RESULTS: A cross-section study with 1396 hospitalized diabetes participants from department of endocrinology and neurology were performed and the propensity score matching method was applied to reduce the effects of confounding factors between the matched PAD and Non-PAD groups. The relationship between urinary ACR and ankle-brachial index (ABI) was analyzed by linear curve fitting analyses and multiple logistic regression models. Our study showed that the prevalence of PAD (low ABI, ABI<0.9) was 7.09% in our diabetes patients. The ABI level was significantly lower in high ACR group compared with those in normal urinary ACR group (1.11 ± 0.17 vs 1.13 ± 0.15, p = 0.010). The prevalence of PAD was increased with the increased tertile's of log2-transformed ACR in total patients before and after propensity score matching (p < 0.001 and p = 0.007, respectively). The OR (95% CI) between log2-transformed ACR and PAD was 1.0 and 1.70 (1.08-2.69, p = 0.022) respectively in normal and high ACR levels in diabetes patients after adjusting for potential confounders. After propensity score matching, the OR (95% CI) between log2-transformed ACR and PAD was 1.0 and 1.85 (1.05-3.23, p = 0.031) respectively in normal and high ACR levels in diabetes patients after adjusting for potential confounders. CONCLUSION: The elevated urinary ACR level was associated with PAD in Chinese diabetes patients.


Assuntos
Diabetes Mellitus , Doença Arterial Periférica , Humanos , Creatinina/urina , População do Leste Asiático , Pontuação de Propensão , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/epidemiologia , Índice Tornozelo-Braço , Fatores de Risco , Extremidade Inferior , Albuminas
6.
Phytother Res ; 37(5): 1986-1996, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36609866

RESUMO

This study was designed to evaluate antiplatelet effect and therapeutic effect of ginkgo diterpene lactone meglumine injection (GDLI) in acute ischemic stroke (AIS) patients. In this randomized, double-blind, placebo-controlled trial, we randomly assigned 70 inpatients within 48 hr after the onset of AIS to combination therapy with GDLI and aspirin (GDLI at a dose of 25 mg/d for 14 days plus aspirin at a dose of 100 mg/d for 90 days) or to placebo plus aspirin in a ratio of 1:1. Platelet function, the National Institute of Health Stroke Scale (NIHSS), and the modified Rankin Scale (mRS) were evaluated. A good outcome was defined as NIHSS scores decrease ≥5 or mRS scores decrease ≥2. Results showed that arachidonic acid induced maximum platelet aggregation rate (AA-MAR) and mean platelet volume (MPV) of the GDLI-aspirin group were much lower than that of the aspirin group (p = 0.013 and p = 0.034, respectively) after the 14-day therapy. The combination of GDLI and aspirin was superior to aspirin alone, and had significant impact on the good outcome at day 90 (ORadj 7.21 [95%CI, 1.03-50.68], p = 0.047). In summary, GDLI has antiplatelet effect and can improve the prognosis of AIS patients.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , AVC Isquêmico/tratamento farmacológico , Ginkgo biloba , Aspirina/farmacologia , Aspirina/uso terapêutico
7.
J Am Chem Soc ; 144(11): 4845-4852, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35167256

RESUMO

Accomplishing optical activity in achiral materials has long been a challenge. Achiral nanomaterials that crystallize in achiral point groups are generally optically inactive. Herein we report the surprising observation of optical activity in several achiral point groups for supercrystals assembled from anisotropic metal nanoclusters with atomic precision. By analyzing multiple achiral nanoclusters with different molecular structures and symmetry space groups, we have identified that the molecular anisotropy of nanocluster entities and their asymmetric arrangement in point groups of supercrystals are the two key factors for the realization of optical activity in such supercrystals. We have further exploited the polarization effect of the nanocluster supercrystals as a polarization switch that can alter the polarized state of the linearly polarized light. Our findings have broadened the fundamental principles for producing nanomaterial-based optical activity and devices with polarization effects.


Assuntos
Nanoestruturas , Anisotropia , Cristalografia , Estrutura Molecular , Rotação Ocular
8.
Neuroimmunomodulation ; 29(4): 296-305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34903694

RESUMO

OBJECTIVE: At present, studies on lymphocytes are mostly conducted on CD19+ B cells and CD27+ B cells in neuromyelitis optica spectrum disorders (NMOSDs), but the exact changes in lymphocyte subsets (CD19+ B cells, CD3+ T cells, CD4+ Th cells, CD8+ Ts cells, the CD4+/CD8+ ratio, and NK [CD56+ CD16] cells) have rarely been studied. This study aimed to assess lymphocyte subset changes in patients with NMOSD. METHODS: We performed a cross-sectional study of consecutive patients with acute NMOSD (n = 41), chronic NMOSD (n = 21), and healthy individuals (n = 44). Peripheral blood samples were obtained upon admission, and lymphocyte subsets were analyzed by flow cytometry. Levels of lymphocyte subsets among 3 groups were compared and its correlation with the length of spinal cord lesions was analyzed. RESULTS: The levels of peripheral blood CD19+ B cells were significantly higher in patients with acute and chronic NMOSD than in healthy controls (HCs) (17.91 ± 8.7%, 13.08 ± 7.562%, and 12.48 ± 3.575%, respectively; p < 0.001) and were positively correlated with the length of spinal cord lesions in acute NMOSD (r = 0.433, p < 0.05). The peripheral blood CD4+/CD8+ ratio was significantly lower in patients with acute NMOSD and chronic NMOSD than in HCs (1.497 ± 0.6387, 1.33 ± 0.5574, and 1.753 ± 0.659, respectively; p < 0.05), and the levels of peripheral blood NK (CD56+ CD16) cells were significantly lower in patients with acute and chronic NMOSD than in HCs (13.6 ± 10.13, 11.11 ± 7.057, and 14.7 [interquartile range = 9.28], respectively; p < 0.01). CONCLUSIONS: The levels of certain subsets of peripheral blood lymphocytes are associated with disease status in NMOSD.


Assuntos
Neuromielite Óptica , Humanos , Estudos Transversais , Subpopulações de Linfócitos/patologia , Contagem de Linfócitos , Antígenos CD19
9.
Nanotechnology ; 33(13)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34933293

RESUMO

P-type nanostructured photodetectors and phototransistors have been widely used in the field of photodetection due to their excellent electrical and optoelectronic characteristics. However, the large dark current of p-type photodetectors will limit the detectivity. Herein, we synthesized small-diameter single-crystalline p-type SnS nanowires (NWs) and then fabricated single SnS NW photodetectors and phototransistors. The device exhibits low noise and low dark current, and its noise current power is as low as 2.4 × 10-28A2. Under 830 nm illumination and low power density of 0.12 mW cm-2, the photoconductive gain, responsivity and detectivity of the photodetector are as high as 3.9 × 102, 2.6 × 102A W-1and 1.8 × 1013Jones, respectively, at zero gate voltage. The rise and fall time of response are about 9.6 and 14 ms. The experimental results show that the small-diameter p-type SnS NWs have broad application prospects in high-performance and low-power photodetectors with high sensitivity, fast response speed and wide spectrum detection in the future.

10.
Neurol Sci ; 43(3): 1831-1838, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34518934

RESUMO

OBJECTIVE: We investigated rate-dependent depression (RDD) of the Hoffman reflex (H-reflex) in patients with amyotrophic lateral sclerosis (ALS), a degenerative disease with ventral horn involvement. PATIENTS AND METHODS: In this case-control study, we enrolled 27 patients with ALS and 30 matched healthy control subjects. Clinical and electrophysiological assessments, as well as RDD in response to various stimulation frequencies (0.5 Hz, 1 Hz, 3 Hz and 5 Hz), were compared between groups. Multiple clinical and electrophysiological factors were also explored to determine any underlying associations with RDD. RESULTS: The ALS group showed a significant loss of RDD across all frequencies compared to the control group, most notably following 1 Hz stimulation (19.1 ± 20.3 vs. 34.0 ± 13.7%, p = 0.003). Among factors that might influence RDD, the enlargement of the motor unit potential (MUP) showed a significant relationship with RDD following multifactor analysis of variance (p = 0.007) and Pearson correlation analysis (ρ = - 0.70, p < 0.001), while various upper motor neuron manifestations were not correlated with RDD values (p > 0.05). CONCLUSION: We report a loss of RDD in patients with ALS. The strong correlation detected between the RDD deficit and increased MUP suggests that RDD is a sensitive indicator of underlying spinal disinhibition in ALS. TRIAL REGISTRATION: ChiCTR2000038848, 10/7/2020 (retrospectively registered), http://www.chictr.org.cn/ .


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/complicações , Estudos de Casos e Controles , Depressão , Fenômenos Eletrofisiológicos , Humanos , Neurônios Motores/fisiologia
11.
Appl Opt ; 61(2): 540-545, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35200895

RESUMO

A novel method called even-power phase modulation is proposed in a self-mixing displacement sensor to improve measuring accuracy, to the best of our knowledge, which is realized by combining the even-power fast algorithm with the sinusoidal phase-modulation method. By performing the even-power fast algorithm in the self-mixing interference system, the spectrum of harmonic components is broadened. In this case, the extracted first and second harmonic components in the frequency domain contain rich information, and the displacement of the target can be accurately reconstructed. The principle and signal processing approach are introduced in detail, and the simulation results show that the reconstruction error can be effectively reduced compared with the electro-optic modulator phase modulation method. A series of experiments at different vibration amplitudes is conducted to confirm the feasibility and effectiveness of the method. An amplitude of 120 nm is proved to be measurable, and the absolute error is 10 nm, which shows great potential in the field of non-contact nanometer vibration measurement sensors.

12.
BMC Surg ; 22(1): 315, 2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-35964028

RESUMO

OBJECTIVE: This study aims to investigate the efficacy and safety of intraoperative real time ultrasound-assisted flexible ureteroscopic holmium laser incision and internal drainage in the treatment of parapelvic cysts, and to review recently published relevant literature. METHOD: This is a retrospective study in which the clinical data of 47 patients who underwent flexible ureteroscopic holmium laser incision and internal drainage of parapelvic cysts in our center from March 2017 to March 2021 were retrospectively analyzed. A literature search was conducted to review and summarize relevant reports on endoscopic treatment of parapelvic cysts published in the past 10 years. RESULTS: Among 47 patients with parapelvic cysts who underwent flexible ureteroscopic holmium laser incision and internal drainage, 12 (25.53%) cases had a typical cyst wall bulging into the collecting system under flexible ureteroscope. As the cyst wall was thin and translucent in these cases, ultrasound was not used during the operation. The cysts of the remaining 35 patients were located with the aid of intraoperative real time ultrasound, and all underwent successful operation. No serious surgical complications occurred after surgery. The patients were followed up for 12-24 months after operation. The cyst in one case was observed larger than its original size before operation, so recurrence was considered. In another two cases, the diameters of the cysts were more than half of their original diameters before operation. Thus, the efficacy was poor in the three cases. For the remaining 44 cases, there was no obvious cyst observed or the diameter of the cysts was less than half their preoperative level. CONCLUSION: The approach of ultrasound-assisted flexible ureteroscopic holmium laser incision and internal drainage in the treatment of parapelvic cysts is safe and effective, which helps to solve the problem of localization of atypical parapelvic cysts on endoscopic findings.


Assuntos
Cistos , Doenças Renais Císticas , Lasers de Estado Sólido , Cistos/cirurgia , Drenagem , Humanos , Doenças Renais Císticas/cirurgia , Lasers de Estado Sólido/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Ureteroscopia
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(11): 1259-1265, 2022 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-36398553

RESUMO

OBJECTIVES: To investigate the risk factors for acute kidney injury (AKI) in children with cardiac arrest (CA) and the influencing factors for prognosis. METHODS: A retrospective analysis was performed on the medical records of the children who developed CA in the pediatric intensive care unit (PICU) of Hunan Children's Hospital from June 2016 to June 2021. According to the presence or absence of AKI within 48 hours after return of spontaneous circulation (ROSC) for CA, the children were divided into two groups: AKI (n=50) and non-AKI (n=113). According to their prognosis on day 7 after ROSC, the AKI group was further divided into a survival group (n=21) and a death group (n=29). The multivariate logistic regression analysis was used to investigate the risk factors for early AKI in the children with CA and the influencing factors for prognosis. RESULTS: The incidence rate of AKI after CA was 30.7% (50/163). The AKI group had a 7-day mortality rate of 58.0% (29/50) and a 28-day mortality rate of 78.0% (39/50), and the non-AKI group had a 7-day mortality rate of 31.9% (36/113) and a 28-day mortality rate of 58.4% (66/113). The multivariate logistic regression analysis showed that long duration of cardiopulmonary resuscitation (OR=1.164, 95%CI: 1.088-1.246, P<0.001), low baseline albumin (OR=0.879, 95%CI: 0.806-0.958, P=0.003), and adrenaline administration before CA (OR=2.791, 95%CI: 1.119-6.961, P=0.028) were closely associated with the development of AKI after CA, and that low baseline pediatric critical illness score (OR=0.761, 95%CI: 0.612-0.945, P=0.014), adrenaline administration before CA (OR=7.018, 95%CI: 1.196-41.188, P=0.031), and mechanical ventilation before CA (OR=7.875, 95%CI: 1.358-45.672, P=0.021) were closely associated with the death of the children with AKI after CA. CONCLUSIONS: Albumin should be closely monitored for children with ROSC after CA, especially for those with long duration of cardiopulmonary resuscitation, low baseline pediatric critical illness score, adrenaline administration before CA, and mechanical ventilation before CA, and such children should be identified and intervened as early as possible to reduce the incidence of AKI and the mortality rate.


Assuntos
Injúria Renal Aguda , Parada Cardíaca , Criança , Humanos , Prognóstico , Estudos Retrospectivos , Estado Terminal , Parada Cardíaca/complicações , Injúria Renal Aguda/epidemiologia , Unidades de Terapia Intensiva Pediátrica , Fatores de Risco , Epinefrina , Albuminas
14.
Hum Mutat ; 42(11): 1443-1460, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34298581

RESUMO

Phenotypes of some rare genetic diseases are atypical and it is a challenge for pediatric intensive care units (PICUs) to diagnose and manage such patients in an emergency. In this study, we investigated 58 PICU patients (39 deceased and 19 surviving) in critical ill status or died shortly without a clear etiology. Whole exome sequencing was performed of 103 DNA samples from their families. Disease-causing single-nucleotide variants (SNVs) and copy number variants (CNVs) were identified to do genotype-phenotypes analysis. In total, 27 (46.6%) patients received a genetic diagnosis. We identified 34 pathogenic or likely pathogenic SNVs from 26 genes, which are related to at least 19 rare diseases. Each rare disease involved an isolated patient except two patients caused by the same gene ACAT1. The genotypic spectrum was expanded by 23 novel SNVs from gene MARS1, PRRT2, TBCK, TOR1A, ECE1, ARX, ZEB2, ACAT1, CPS1, VWF, NBAS, COG4, and INVS. We also identified two novel pathogenic CNVs. Phenotypes associated with respiratory, multiple congenital anomalies, neuromuscular, or metabolic disorders were the most common. Twenty patients (74.1%) accompanied severe infection, 19 patients (70.1%) died. In summary, our findings expanded the genotypes and phenotypes of 19 rare diseases from PICU with complex characteristics.


Assuntos
Sequenciamento do Exoma , Genótipo , Unidades de Terapia Intensiva Pediátrica , Fenótipo , Doenças Raras/genética , Adolescente , Criança , Pré-Escolar , Feminino , Heterozigoto , Humanos , Lactente , Masculino
15.
Opt Lett ; 46(1): 114-117, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33362029

RESUMO

A fiber autodyne laser feedback displacement sensor based on the effect of the frequency shift is demonstrated. The all-fiber structure enables our system to be easily employed in diverse complex and narrow scenes. By virtue of adopting an ultra-high sensitivity distributed Bragg reflector (DBR) fiber laser as the laser source and the frequency-shift technology to avoid the phenomenon that the measured signal of the low frequency is submerged in the noise, the measurement of the sub-picometer displacement under weak feedback condition has been achieved, which shows a great potential in the field of micro-vibration measurement. Moreover, the proposed system has advantages such as simplicity in system structure, low cost of implementation, and immunity to electromagnetic interference.

16.
Opt Lett ; 46(15): 3805-3808, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329286

RESUMO

This Letter proposes an all-fiber self-mixing interferometric method based on laser feedback technology with long transmission distance, which has advantages of high sensitivity and compact structure. We theoretically and experimentally verify that the measurement distance of the self-mixing sensor is not limited to the coherence length of the solitary laser used. In the experiment, the velocity of a non-cooperative target was successfully measured with 40 km transmission distance. Therefore, the all-fiber self-mixing Doppler velocimeter has a great application prospect in the field of remote sensing measurement. Its unique flexibility can be applied to a variety of complex environments of non-cooperative target measurement.

17.
Opt Lett ; 46(6): 1229-1232, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720154

RESUMO

The theoretical basis and experimental realization of an all-fiber self-mixing laser Doppler velocimetry based on frequency-shifted feedback in a distributed feedback (DFB) fiber laser are presented, which employs a pair of fiber-coupled acousto-optic modulators to adjust the modulation intensity and frequency of the laser self-mixing effect. Moreover, the minimum optical feedback intensity for the velocity signal successfully measured by the interferometer is 5.12 fW, corresponding to 0.16 photons per Doppler cycle. The results demonstrate that the proposed scheme can adapt to the non-contact measurement requirements of the wide-range speed and weak feedback level in the complex environment.

18.
Neurol Sci ; 42(6): 2223-2233, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33782779

RESUMO

There are bunch of autoantibodies, particularly autoantibodies against proteins located at the node of Ranvier, have been discovered and transformed the clinical management of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Neurofascin (NF) plays an important role in both the nodal and paranodal regions of the node of Ranvier. In this review, we focus on the two characteristic forms of neurofascin: NF186 and NF155, comparing the similarities and differences between them, reviewing the current knowledge on genetic backgrounds, pathogenesis, clinical manifestations, and management of patients with anti-neurofascin positive CIDP. Autoantibodies against neurofascin were mainly IgG4 isotype. Mutation of NFASC gene in human causes severe neurodevelopment disorders, and HLA DRB1*15 may be a strong risk factor for the development of anti-NF155 antibodies. Motor impairment, sensory ataxia, and tremor were the typical presentations of patients with anti-NF155+ CIDP, while tetraplegia and cranial nerve involvement were more common in patients with anti-NF186+ CIDP. Recent studies have depicted a relatively clear picture of anti-NF155+ CIDP, and the strong clinical correlation of NF186 with CIDP remains unclear. The genetic background of neurofascin will assist in future explorations.


Assuntos
Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Autoanticorpos , Moléculas de Adesão Celular/genética , Patrimônio Genético , Humanos , Fatores de Crescimento Neural/genética , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/genética
19.
Neurol Sci ; 42(11): 4673-4681, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33723708

RESUMO

INTRODUCTION: Neurofascin (NF) is critical for the formation and maintenance of Ranvier nodes. NF186, the neuronal form of NF, localizes in the initial segment of axon and Ranvier node. NF186 antibody has been detected in demyelinating diseases of both central nervous system (CNS) and peripheral nervous system (PNS). AIMS: To evaluate the clinical features of patients with anti-NF186 IgG neuropathy. METHODS: Sixteen patients (16/138) with serum-positive anti-NF186 IgG were included and divided into groups of either CNS or PNS-involved according to their clinical manifestations. Anti-NF186 IgG was detected by cell-based assays. RESULTS: In 7 patients who were confirmed to have CNS involvement, the most frequent symptoms were dizziness (57%) and vision impairment (43%); lesions in centrum semiovale, cerebellum, and meninges were shown by magnetic resonance imaging (MRI). In comparison, limb weakness (78%) and numbness (78%) were the most common symptoms in PNS-involved patients; axonal loss and demyelination were confirmed by nerve conduction examinations. Elevated level of cerebrospinal fluid (CSF) protein was found in 12 cases without statistically significant difference between the CNS and PNS groups. Meanwhile, CSF white blood cell counts were found significantly elevated in CNS-involved patients compared with patients of PNS group. Thirteen patients received immunomodulating treatments, and patients with chronic onset and progressive course showed poor response to the therapies. CONCLUSIONS: Patients with anti-NF186 IgG neuropathy showed no specific symptoms or signs. It is worth noting that quite a few patients show CNS-impaired signs only, and cranial MRI is essential for the screening of CNS involvement.


Assuntos
Fatores de Crescimento Neural , Doenças do Sistema Nervoso Periférico , Moléculas de Adesão Celular , Sistema Nervoso Central , Humanos , Nós Neurofibrosos
20.
Appl Opt ; 60(19): 5678-5681, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263861

RESUMO

By using different active materials as gain media, we demonstrate a system aimed to measure the fluorescence lifetime of gain media in the fiber laser by utilizing the correlation between the laser's relaxation oscillation characteristics and the fluorescence lifetime of the active materials. As the advantages of extremely compact configuration, non-destructive and real time of the system, the fluorescence lifetime of gain media composed of materials of erbium-ytterbium-doped or erbium-doped have been measured, whose results are 20.2 µs and 1.62 ms, respectively. The proposed method provides a new, to the best of our knowledge, idea for real-time monitoring of fluorescence lifetime in the fiber laser.

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