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1.
Nature ; 601(7891): 49-52, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34987214

RESUMO

Magnetic fields have an important role in the evolution of interstellar medium and star formation1,2. As the only direct probe of interstellar field strength, credible Zeeman measurements remain sparse owing to the lack of suitable Zeeman probes, particularly for cold, molecular gas3. Here we report the detection of a magnetic field of +3.8 ± 0.3 microgauss through the H I narrow self-absorption (HINSA)4,5 towards L15446,7-a well-studied prototypical prestellar core in an early transition between starless and protostellar phases8-10 characterized by a high central number density11 and a low central temperature12. A combined analysis of the Zeeman measurements of quasar H I absorption, H I emission, OH emission and HINSA reveals a coherent magnetic field from the atomic cold neutral medium (CNM) to the molecular envelope. The molecular envelope traced by the HINSA is found to be magnetically supercritical, with a field strength comparable to that of the surrounding diffuse, magnetically subcritical CNM despite a large increase in density. The reduction of the magnetic flux relative to the mass, which is necessary for star formation, thus seems to have already happened during the transition from the diffuse CNM to the molecular gas traced by the HINSA. This is earlier than envisioned in the classical picture where magnetically supercritical cores capable of collapsing into stars form out of magnetically subcritical envelopes13,14.

2.
Nature ; 609(7928): 685-688, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36131036

RESUMO

Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (AU; Earth-Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.

3.
Nature ; 606(7916): 873-877, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35676486

RESUMO

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately [Formula: see text] parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies2,6, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.

4.
Nature ; 607(7918): 256-259, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831603

RESUMO

Fast radio bursts (FRBs) are millisecond-duration flashes of radio waves that are visible at distances of billions of light years1. The nature of their progenitors and their emission mechanism remain open astrophysical questions2. Here we report the detection of the multicomponent FRB 20191221A and the identification of a periodic separation of 216.8(1) ms between its components, with a significance of 6.5σ. The long (roughly 3 s) duration and nine or more components forming the pulse profile make this source an outlier in the FRB population. Such short periodicity provides strong evidence for a neutron-star origin of the event. Moreover, our detection favours emission arising from the neutron-star magnetosphere3,4, as opposed to emission regions located further away from the star, as predicted by some models5.

5.
Nature ; 598(7880): 267-271, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34645999

RESUMO

The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown1,2. As the first precisely localized source, FRB 121102 (refs. 3-5) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution6-8. However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h-1, in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 1037 erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions.

6.
Nature ; 587(7832): 63-65, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33149293

RESUMO

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

7.
Nature ; 577(7789): 190-194, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31907402

RESUMO

Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes1,2. Their physical origin remains unknown, but dozens of possible models have been postulated3. Some FRB sources exhibit repeat bursts4-7. Although over a hundred FRB sources have been discovered8, only four have been localized and associated with a host galaxy9-12, and just one of these four is known to emit repeating FRBs9. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source6, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure6 further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.

8.
Clin Radiol ; 79(8): 618-627, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797608

RESUMO

AIM: We aimed to compare the diagnostic performance of transvaginal sonography (TVS) versus magnetic resonance imaging (MRI) in identifying deep infiltrating endometriosis (DIE) in the rectovaginal septum (RVS) of affected patients. MATERIALS AND METHODS: An extensive search was conducted in the PubMed, Embase databases to identify available publications up to November 2023. Studies evaluating the diagnostic perfor-mance of TVS and MRI for DIE in patients with rectovaginal septum involvement were all included. Sensitivity and specificity analyses employed the DerSi-monian and Laird method, complemented by the Freeman-Tukey double arc-sine trans-formation. Additionally, the study quality was rigorously evaluated using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) method. RESULTS: The meta-analysis encompassed 8 articles with a total of 721 patients. It revealed that the overall sensitivity of TVS was 0.51 (95% CI: 0.31-0.72), contrasted with 0.74 (95% CI: 0.66-0.82) for MRI. This finding suggests a higher sensitivity of MRI compared to TVS (P=0.04). Conversely, the overall specificity was 0.97 (95%CI: 0.94-1.00) for TVS and 0.93 (95% CI: 0.84-0.99) for MRI, indicating a comparable level of specificity between the two modalities (P=0.22). CONCLUSION: Our meta-analysis reveals that MRI exhibits higher sensitivity and comparable specificity to TVS in patients with DIE of the RVS. However, the limited number of articles included may affect the evidence of these results. Therefore, further d number of articles included may affect the evidence of these results. Therefore, further research with larger sample sizes and prospective designs is essential to validate these findings.


Assuntos
Endometriose , Imageamento por Ressonância Magnética , Reto , Ultrassonografia , Vagina , Humanos , Endometriose/diagnóstico por imagem , Feminino , Imageamento por Ressonância Magnética/métodos , Ultrassonografia/métodos , Vagina/diagnóstico por imagem , Reto/diagnóstico por imagem , Sensibilidade e Especificidade
9.
Appl Opt ; 63(4): 976-981, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437394

RESUMO

The synthetic aperture infrared radio imaging method based on laser local oscillator coherent detection has potential application value for astronomical observations. This paper studies the multi-channel synthetic aperture infrared imaging method and conducts experimental verification using a principle prototype. In the short-wave infrared band, five beam-expanding fiber collimators are used to build an observation structure of five laser local oscillator coherent detection channels at a near-field distance of 5 m to carry out physical experiments. The laser local oscillator wavelength is 1.55 µm, and the AD sampling rate is 4 GHz. For the infrared radiation source signal, the phase relationship of the infrared signals between channels acquired by the prototype principle is stable, and the five-channel synthetic aperture imaging results are consistent with the computer simulated results. The experiment verified the effectiveness of the laser local oscillator comprehensive aperture infrared radio imaging method.

10.
Public Health ; 227: 202-209, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241901

RESUMO

OBJECTIVES: This study aims to reveal the single and mixed associations of PM2.5 and its components with very, moderately, and late preterm births and to explore the potential mediating role of pregnancy complications in PM2.5-induced preterm birth. STUDY DESIGN: This was a retrospective cohort study. METHODS: We enrolled 168,852 mothers and matched the concentrations of PM2.5 and its five components (OM, SO42-, BC, NO3-, and NH4+) based on their geographical location. Next, we used generalized linear models, quantile g-computation, and mediation analysis to evaluate the associations of PM2.5 and its components with very, moderately, and late preterm births and the mediating role of pregnancy complications. RESULTS: Prenatal exposure to PM2.5 and its components was associated with preterm birth, and the association was strongest in the third trimester. Preterm birth was associated with co-exposure to a mixture of PM2.5 components in the third trimester, and the contributions of NO3-, NH4+, and BC to the risk of preterm birth were positive. Meanwhile, pregnancy complications mediated PM2.5-induced preterm birth. Moreover, very and moderately preterm births were associated with PM2.5 and its components in the second and third trimesters, and very and late preterm births were associated with co-exposure to a mixture of PM2.5 components in the third trimester. CONCLUSIONS: Later exposure to PM2.5 during pregnancy will cause earlier preterm birth. Targeted and positive interventions for anthropogenic sources of specific PM2.5 components and pregnancy complications are helpful for preterm birth prevention.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Complicações na Gravidez , Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Feminino , Recém-Nascido , Humanos , Nascimento Prematuro/epidemiologia , Estudos de Coortes , Material Particulado/efeitos adversos , Material Particulado/análise , Estudos Retrospectivos , Exposição Materna/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China
11.
Zhonghua Yi Xue Za Zhi ; 104(29): 2767-2772, 2024 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-39075997

RESUMO

Objective: To analyze the imaging characteristics and surgical effect for symmetrical lumbar hemivertebrae in pediatric patients. Methods: The data of 13 patients with hemivertebrae locating in the lumbar spine symmetrically were retrospectively analyzed, and all the patients were treated in Beijing Children's Hospital from January 2015 to September 2021. The mean age of the patients was 6.2 (2.9, 9.3) years. There were 8 males and 5 females. The data of coronal/sagittal plane including segmental Cobb angle, cranial/caudal compensatory curve, thoracic kyphosis, thoracolumbar kyphosis, sacral obliquity, and lumbar lordosis were recorded through long cassette spinal radiographs. Associated anomalies and the relationship between hemivertebrae and posterior component were recorded through computerized tomography (CT) and magnetic resonance imaging (MRI). All the patients received surgery, and their pre-and postoperative imaging data were compared. Results: A total of 26 hemivertebraes were found, in which 80.8% (21/26) located below L2. Hemivertebraes in 10 patients were separated by a mean 1-2 normal vertebrae. Most hemivertebraes along with the corresponding posterior component were unison (21/26, 80.8%). The Cobb angles of cranial compensatory curve (13.9°±7.2°) was more serious than that of caudal compensatory curve (5.5°±5.0°)(P=0.04). The lumbar lordosis and thoracic kyphosis was 20.2°±15.0° and 18.7°±9.2°, respectively. Six patients complicated with sacral obliquity, while 7 patients complicated with thoracolumbar lordosis. Associated anomalies were found in 6 (46.2%) patients through CT and MRI. Eleven patients received one-or two-stage posterior hemivertebrae resection with short segmental fusion, and 2 patients received one-stage hemivertebrae resection with long segmental fusion. All the surgery were completed successfully without serious complications such as nerve injury, infection, and implant failure. The mean follow-up period was (42.4±10.2) months. At the last follow-up point, the correction rate of segmental Cobb angle and cranial compensatory curve was 83.3%±15.6% and 38.1%±10.4%, respectively, showing significant improvement (P<0.05). Although the caudal compensatory curve, sacral obliquity, and thoracic kyphosis improved after surgery, the data showed no significant difference compared to that before surgery. Thoracolumbar lordosis in all patients were corrected. Conclusions: Most hemivertebraes in such spinal deformity locate in lower lumbar region with a high incidence of anomalies. Individualized treatment based on patients' condition is essential for the complicated spinal deformity.


Assuntos
Cifose , Vértebras Lombares , Escoliose , Humanos , Masculino , Feminino , Estudos Retrospectivos , Criança , Vértebras Lombares/anormalidades , Vértebras Lombares/cirurgia , Vértebras Lombares/diagnóstico por imagem , Escoliose/cirurgia , Escoliose/diagnóstico por imagem , Pré-Escolar , Cifose/cirurgia , Cifose/diagnóstico por imagem , Vértebras Torácicas/anormalidades , Vértebras Torácicas/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Corpo Vertebral/anormalidades , Corpo Vertebral/diagnóstico por imagem , Lordose/diagnóstico por imagem
12.
Zhonghua Yi Xue Za Zhi ; 104(20): 1825-1830, 2024 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-38782750

RESUMO

Objectives: To analyze the clinical characteristics and prognosis of medullary thyroid microcarcinoma (MTMC). Methods: A case series studies. The clinical data of patients with medullary thyroid carcinoma (MTC) diagnosed by postoperative pathology and with complete follow-up data who were initially treated in Tianjin Medical University Cancer Hospital from January 2013 to December 2019 were retrospectively analyzed. There were a total of 170 cases, including 70 males and 100 females, aged (49.7±12.3) years old. Among them, there were 61 patients with MTMC. They were divided into group A (with a maximum tumor idameter of ≤0.5 cm, n=13) and group B (with a maximum tumor diameter >0.5~≤1.0 cm, n=48) based on whether the maximum diameter of the tumor was >0.5 cm. Analysis was conducted on their pathological results and prognosis. Results: Among the MTC, MTMC accounted for 26.4% (61/231) with 26 males and 35 females aged Mï¼»Q1,Q3ï¼½51.0 (41.0, 59.0) years. Among the MTMC patients, 57.4% (35/61) were in stage Ⅰ, 16.4% (10/61) were in stage Ⅲ, and 26.2% (16/61) were in stage Ⅳ. For MTMC with a maximum diameter of≤0.5 cm and a maximum diameter of >0.5-≤1.0 cm, there was no statistically significant difference between the two groups in terms of gender, age, mixed cancer, invasion of glandular lobes, multifocal, central lymph node metastasis, lateral neck lymph node metastasis rate and other pathological characteristics(both P>0.05). In terms of prognosis, the recurrence free survival time of MTMC patients was 83.1 (68.0, 97.0) months. Among them, structural tumor recurrence occurred in 5 patients (8.2%) after surgery, and 1 patient (1.6%) died. The expected 5-year and 10-year survival rates were 93.4% and 89.0%, respectively. There was no statistically significant difference in recurrence free survival time among MTMC patients, MTC patients with a maximum diameter of >1.0-≤2.0 cm, and MTC patients with a maximum diameter of >2.0 cm (all P>0.05). Conclusion: MTMC has strong invasiveness, and although the prognosis of most MTMCs is relatively good, the risk of long-term recurrence and death is still high.


Assuntos
Carcinoma Neuroendócrino , Neoplasias da Glândula Tireoide , Humanos , Masculino , Feminino , Neoplasias da Glândula Tireoide/patologia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/diagnóstico , Metástase Linfática , Adulto , Recidiva Local de Neoplasia
13.
Zhonghua Yi Xue Za Zhi ; 104(1): 22-30, 2024 Jan 02.
Artigo em Chinês | MEDLINE | ID: mdl-38178764

RESUMO

Objective: To investigate the correlations between cosmetic and radiographic parameters of shoulder balance, as well as the variations in cosmetic shoulder balance observed from different perspectives, among patients with adolescent idiopathic scoliosis (AIS) characterized by thoracic curves. Methods: A total of 43 patients with thoracic curves treated from July to October in 2022 in Nanjing Drum Tower Hospital were recruited in this study. There were 9 males and 34 females with a mean age of (14.3±1.5) years. All participants underwent comprehensive radiographic assessments and were photographed both from posterior and anterior views, focusing on the shoulder region as well as a higher level (maintaining a consistent vertical distance of 180 cm from the ground). Six cosmetic parameters were measured on the photographs: shoulder angle(α1), axilla angle(α2), shoulder area index 1(SAI1), shoulder area index 2 (SAI2), inner shoulder height (SHi) and outer shoulder height (SHo). Eight radiographic parameters were measured on the radiographs: radiographic shoulder height difference (RSHD), first rib angle (FRA), clavicle-rib cage intersection (CRCI), coracoid process height (CPH), T1 tilt, clavicle angle(CA), clavicle chest cage angle difference (CCAD) and Cobb angle. Differences among bilateral cosmetic indicators from different perspectives were analyzed and compared, and their correlation with bilateral radiographic indicators was studied. Results: There was no significant differences between anterior cosmetic parameters and posterior cosmetic parameters at the same level of observation(all P>0.05). However, when observing SHi, SHo, α1, and α2 at the shoulder level, it became evident that they exhibited significantly higher values compared to the corresponding higher level on the same side of the patients' bodies. This contrast was observed in both the dorsal [SHo: (0.11±1.20) cm vs (-0.44±1.39) cm, P=0.005; SHi: (0.64±0.86) cm vs (0.32±0.56) cm, P=0.003; α1:-0.47°±2.27° vs -0.77°±2.49°, P=0.014; α2:-3.06°±3.23° vs -2.21°±3.03°, P=0.034] and ventral [SHo: (0.12±1.29) cm vs (-0.48±1.35) cm, P=0.007; SHi: (0.61±0.88) cm vs (0.30±0.59) cm, P=0.006; α1:-0.46°±2.18° vs -0.69°±2.35°, P=0.018; α2:-3.26°±3.12° vs -2.05°±2.97°, P=0.029] aspects of the patients. SHi and SHo were more sensitive to this difference of height. The correlation coefficients between radiographic parameters and cosmetic aspects at the shoulder level varied from 0.374 to 0.767. Similarly, the correlation coefficients between radiographic parameters and cosmetic factors at the higher level ranged from 0.273 to 0.579 (all P<0.05). Conclusions: The cosmetic parameters had significant difference between different perspective of observation, the cosmetic parameters are needed to be observed at the shoulder level in the evaluation of patients' shoulder balance.


Assuntos
Cifose , Escoliose , Fusão Vertebral , Masculino , Feminino , Humanos , Adolescente , Criança , Ombro , Vértebras Torácicas , Clavícula , Estudos Retrospectivos
14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(8): 1197-1203, 2024 Aug 06.
Artigo em Chinês | MEDLINE | ID: mdl-39142889

RESUMO

Cerebrospinal fluid (CSF) laboratory tests are important for diagnosing central nervous system (CNS) diseases. Research on intrathecal immunoglobulin-related indexes has gradually attracted attention. The antibody index, which corrects for the effect of individual blood-brain barrier function on CSF antibody test results, is of great significance in the differential diagnosis, efficacy monitoring and prognostic assessment of CNS diseases. It is expected to become a new index for the diagnosis of CNS diseases. This article reviews the concept of antibody index and the research progress of differential diagnosis and treatment of various CNS diseases in order to provide references for the diagnosis, efficacy monitoring and disease progression assessment of CNS diseases.


Assuntos
Doenças do Sistema Nervoso Central , Humanos , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/terapia , Anticorpos
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(1): 18-24, 2024 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-38228545

RESUMO

Objective: To investigate the distribution and hantavirus (HV) carrying state in host animals of hemorrhagic fever with renal syndrome (HFRS) in Henan Province from 2019 to 2022. Methods: Host animal monitoring was carried out at the monitoring sites of HFRS in Henan Province. The real-time fluorescence quantitative PCR was used to detect hantavirus in rat lungs. The types of hantavirus were analyzed. The positive samples were sequenced and then sequence homology and variation were analyzed. Results: A total of 1 308 rodents were captured from 2019 to 2022, 16 specimens of rat lungs tested positive for hantavirus nucleic acid. The positive rate of HV was 1.22% (16/1 308). According to type, the positive rate of HV in Apodius agrarius was the highest (68.75%, 11/16). According to distribution, the positive rate of HV in field samples was the highest (2.50%, 12/480), and the positive rate of HV in residential samples was 0.53% (4/759). The typing results of 16 positive samples showed that all viruses were hantavirus type Ⅰ (hantaan virus). The positive samples were sequenced and eight S gene fragments (GenBank number: OQ681444-OQ681451) and six M gene fragments (OQ681438-OQ681443) were obtained. The S and M gene fragments were similar to the Shaanxi 84FLi strain and Sichuan SN7 strain. Phylogenetic analysis of S and M gene fragments showed that they all belonged to the hantaan virus-H5 subtype. Amino acid sequence analysis revealed that, compared with the hantaan virus vaccine strain 84FLi, the 74th amino acid encoded by eight S fragments was replaced by aspartamide with serine. Tryptophan was replaced by glycine at the 14th position of Gn region in XC2022047, and isoleucine was replaced by alanine at the 359 position of XC2022022 and XC2022024. Conclusion: The hantavirus carried by host animals in Henan Province from 2019 to 2022 belongs to the type Ⅰ (hantaan virus), and Apodemus agrarius is still the dominant host animal of the hantaan virus. Compared with the vaccine strains, amino acid sites are replaced in the immune epitopes of the S and M gene fragments.


Assuntos
Febre Hemorrágica com Síndrome Renal , Orthohantavírus , Vacinas , Animais , Febre Hemorrágica com Síndrome Renal/epidemiologia , Filogenia , Orthohantavírus/genética , Murinae , Aminoácidos/genética
16.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(6): 560-566, 2024 Jun 12.
Artigo em Chinês | MEDLINE | ID: mdl-38858208

RESUMO

The presence of significant complex heterogeneity among patients with acute respiratory distress syndrome (ARDS) is a major reason for the failure of drug treatments. Precision medicine seeks to elucidate the potential mechanisms of ARDS heterogeneity, define subtypes of ARDS patients with specific characteristics, and rapidly identify the patient groups most likely to benefit from targeted treatments, thereby maximizing treatment efficiency and minimizing adverse reactions. This review discusses on the current state of research on ARDS subtypes from multiple perspectives, including etiology, onset time, radiology, pathology, oxygenation index, respiratory mechanics, protein biomarkers, genetics, transcriptomics, and microbiomics, with the aim of deepening the understanding of the pathogenesis of ARDS and thereby guiding precision treatment of ARDS.


Assuntos
Medicina de Precisão , Síndrome do Desconforto Respiratório , Humanos , Síndrome do Desconforto Respiratório/terapia , Medicina de Precisão/métodos , Biomarcadores , Fenótipo
17.
Zhonghua Gan Zang Bing Za Zhi ; 32(6): 532-544, 2024 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-38964896

RESUMO

Objective: To systematically evaluate the effect of hepatitis B virus (HBV) infection on the risk of adverse pregnancy outcomes. Methods: We searched PubMed, Embase, Web of Science, and Cochrane databases. Two researchers independently screened the literature, extracted data, and evaluated the quality. Meta-analysis and cumulative meta-analysis were performed using R4.4.1 software. Fixed/random effects models were used to analyze heterogeneous and non-heterogeneous results. Heterogeneous modifiers were identified by subgroup analysis. Funnel plots and Peters' test were used to analyze potential publication bias. Results: A total of 48 studies involving 92 836 HBsAg-positive pregnant women and 7 123 292 HBsAg-negative pregnant women were included. In terms of adverse pregnancy outcomes, HBV infection was significantly correlated with the occurrence of gestational diabetes mellitus [odds ratio (OR)=1.34, 95% confidence interval (CI): 1.17-1.53] and intrahepatic cholestasis (OR=2.48, 95%CI: 1.88-3.29), with statistically significant differences. In terms of adverse neonatal outcomes, HBV infection was significantly correlated with the occurrence of neonatal asphyxia (OR=1.49, 95%CI: 1.20-1.86) and preterm birth (OR=1.22, 95%CI: 1.12-1.33), with statistically significant differences. In addition, the cumulative meta-analysis demonstrated that the risk of gestational diabetes mellitus and preterm birth both tended to be stable in pregnant women with HBV infection following 2009 and 2010, respectively. The supplementary questions answered for repeated studies had limited significance. Conclusion: Intrahepatic cholestasis, gestational diabetes mellitus, neonatal asphyxia, and preterm birth occurrence risk can be raised with HBV infection in pregnant women.


Assuntos
Hepatite B , Complicações Infecciosas na Gravidez , Resultado da Gravidez , Humanos , Gravidez , Feminino , Hepatite B/epidemiologia , Hepatite B/complicações , Complicações Infecciosas na Gravidez/virologia , Complicações Infecciosas na Gravidez/epidemiologia , Vírus da Hepatite B , Diabetes Gestacional/epidemiologia , Nascimento Prematuro/epidemiologia , Recém-Nascido , Colestase Intra-Hepática/epidemiologia , Fatores de Risco
18.
Zhonghua Gan Zang Bing Za Zhi ; 32(3): 228-234, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38584104

RESUMO

Objective: To analyze the clinical application value of serum heme oxygenase (HO)-1expression level in non-alcoholic fatty liver disease (NAFLD) and, based on that, establish a diagnostic model combined with glucose regulatory protein 78 (GRP78) so as to clarify its diagnostic effectiveness and application value. Methods: A total of 210 NAFLD patients diagnosed by abdominal B-ultrasound and liver elastography were included, and at the same time, 170 healthy controls were enrolled. The general clinical data, peripheral blood cell counts, and biochemical indicators of the research subjects were collected. The expression levels of HO-1 and GRP78 were detected using an enzyme-linked immunosorbent assay. Multivariate analysis was used to screen independent risk factors for NAFLD. Visual output was performed through nomogram diagrams, and the diagnostic model was constructed. Receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA) were used to evaluate the diagnostic effectiveness of NAFLD. Measurement data were analyzed using a t-test or Mann-Whitney U rank sum test to detect data differences between groups. Enumeration data were analyzed using the Fisher's exact probability test or the Pearson χ(2) test. Results: Compared with the healthy control group, the white blood cell count, aspartate aminotransferase (AST), alanine aminotransferase, gamma-glutamyl transferase (GTT), fasting blood glucose (Glu), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), serum HO-1, and GRP78 levels were significantly increased in the NAFLD group patients (P < 0.05). Binary logistic analysis results showed that AST, TG, LDL-C, serum HO-1, and GRP78 were independent risk factors for NAFLD (P < 0.05). A nomogram clinical predictive model HGATL was established using HO-1 (H), GRP78 (G) combined with AST (A), TG (T), and LDL-C (L), with the formula P=-21.469+3.621×HO-1+0.116 ×GRP78+0.674×AST+6.250×TG+4.122 ×LDL-C. The results confirmed that the area under the ROC curve of the HGATL model was 0.965 8, with an optimal cutoff value of 81.69, a sensitivity of 87.06%, a specificity of 92.82%, a P < 0.05, and the diagnostic effectiveness significantly higher than that of a single indicator. The calibration curve and DCA both showed that the model had good diagnostic performance. Conclusion: The HGATL model can be used as a novel, non-invasive diagnosis model for NAFLD and has a positive application value in NAFLD diagnosis and therapeutic effect evaluation. Therefore, it should be explored and promoted in clinical applications.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Glucose , LDL-Colesterol , Heme Oxigenase-1 , Chaperona BiP do Retículo Endoplasmático , Triglicerídeos
19.
Zhonghua Gan Zang Bing Za Zhi ; 32(5): 474-480, 2024 May 20.
Artigo em Chinês | MEDLINE | ID: mdl-38858198

RESUMO

Chronic hepatitis B virus (HBV) infection is one of the major public health issues of ongoing global concern. Due to inadequate understanding of the HBV life cycle, there is a lack of effective drugs to cure chronic hepatitis B. During HBV replication, covalently closed circular DNA (cccDNA) serves as the template for viral replication and can be transcribed to produce five viral RNAs of 3.5, 2.4, 2.1 kb and 0.7 kb in length, which are translated to produce HBeAg, core protein, polymerase (P) protein, HBsAg and HBx proteins, respectively. Among them, the 3.5 kb pregenomic RNA (pgRNA) is also the template for viral reverse transcription. Polymerase protein recognizes and binds to the capsid assembly signal on the pgRNA to initiate capsid assembly and reverse transcription. Recent studies have revealed that the processes of splicing, nuclear export, stability, translation, and pgRNA encapsidation of HBV RNAs are regulated by a post-transcriptional regulatory network within the host cell and depend on unique post-transcriptional regulatory elements in the HBV RNA structure. The aim of this review is to overview the post-transcriptional regulatory mechanisms of HBV RNA and their applications in the study of HBV antiviral therapeutics, with the aim of providing new ideas for the development of new drugs targeting HBV RNA.


Assuntos
Vírus da Hepatite B , RNA Viral , Replicação Viral , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , RNA Viral/metabolismo , Humanos , Antivirais/farmacologia , Regulação Viral da Expressão Gênica , Hepatite B Crônica/virologia , Hepatite B Crônica/tratamento farmacológico , Processamento Pós-Transcricional do RNA
20.
Zhonghua Wai Ke Za Zhi ; 62(3): 187-193, 2024 Mar 01.
Artigo em Chinês | MEDLINE | ID: mdl-38291634

RESUMO

Objectives: To investigate the clinical efficacy of unilateral biportal endoscopy (UBE) in the treatment of degenerative lumbar disease (DLD) and its impact on postoperative lumbar stability. Methods: This is a retrospective case series study. A total of 109 cases of DLD treated with UBE in the Department of Orthopaedic, Beijing Chaoyang Hospital Affiliated to Capital Medical University from July 2020 to June 2022 were analyzed retrospectively. There were 47 males and 62 females, aged (53.3±8.2) years (range: 21 to 80 years). The surgical segments were single segment in 80 cases, two segments in 25 cases, and three segments in 4 cases. The low back pain and leg pain of visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) score and Oswestry disability index (ODI) were evaluated before and after operation. The modified MacNab criteria were used for evaluation of the clinical consequences. Postoperative three-dimensional lumbar CT was performed to observe the preservation of the facet joints and the angle of the medial surface of the facetectomy(ß angle). At 12 months after surgery, X ray of the flexion and extension lumbar spine were reviewed. The comparison and analysis of the data were conducted using paired sample t tests or generalized estimation equations. Results: All 109 patients underwent operative procedures successfully. The operation time was (94.5±37.1) minutes (range:56 to 245 minutes), the times of X ray was 6.8±4.0 (range:4 to 16 times), and the days of hospitalization was (5.3±3.7) days (range:4 to 14 days). Complications included dural tears in 4 cases, transient lower limb numbness in 4 cases, epidural hematoma in 2 case. The follow-up time was (19.6±7.2) months (range:12 to 36 months). The postoperative low back pain VAS, leg pain VAS, JOA score and ODI were significantly improved(all P<0.05). According to the modified MacNab criteria, the excellent and good rate was 88.99%(97/109) at 12 months after surgery. One case underwent revision surgery because of recurrent lumbar disc herniation. In term of radiographic evaluation, the area of the surgical side facet joints after UBE surgery was reserved more than 60%. The ß angle was less than 90° in all patients. After 12 months of surgery, there was no surgical segment instability or spondylolisthesis by the X-ray of the flexion and extension lumbar spine. Conclusion: UBE can achieve satisfactory clinical efficacy in the treatment of DLD, and maintain the stability of the lumbar spine.


Assuntos
Deslocamento do Disco Intervertebral , Dor Lombar , Fusão Vertebral , Masculino , Feminino , Humanos , Estudos Retrospectivos , Dor Lombar/cirurgia , Endoscopia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Resultado do Tratamento , Vértebras Lombares/cirurgia
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