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1.
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.

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 ; 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.

4.
Nature ; 594(7861): 33-36, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34002091

RESUMO

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

5.
Phys Rev Lett ; 132(13): 131002, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613275

RESUMO

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

6.
Clin Radiol ; 79(5): 363-370, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38290939

RESUMO

AIM: To compare 1-year outcomes of computed tomography venography (CTV) combined with ultrasound-guided minimally invasive treatment with ascending phlebography and ultrasound-guided treatment for recurrent varicose veins. MATERIALS AND METHODS: Consecutive patients with unilateral recurrent varicose veins were matched by gender, age, C classification, and degree of obesity, and randomised in a 1:1 ratio to receive either CTV (CTV group) or ascending phlebography (control group) combined with ultrasound-guided minimally invasive treatment. Patients were followed up by clinical and ultrasound examination. Follow-up was scheduled at 1 week, and 3, 6, and 12 months. The primary outcome measure was the Venous Clinical Severity Score (VCSS) at 12 months. Measures of secondary outcome included Chronic Insufficiency Venous International Questionnaire-20 (CIVIQ-20) score, recurrence of varicose vein or ulcer during 12 months, ulcer healing time, detection and location of treated veins. RESULTS: Eighty patients were enrolled. Median VCSS in the CTV group was lower than it in the control group (p=0.04) and the CIVIQ-20 score was higher than the control group (p=0.02). By 12 months, no symptomatically recurrent varicose veins or ulcers had occurred. The ulcer healing time in CTV group was shorter (p<0.01). A greater number of patients had treated veins detected using CTV than by ascending venography (p=0.01), especially among patients with recurrence reflux veins in the groin, perineum, and vulva (p<0.01). CONCLUSION: CTV combined with ultrasound may be more helpful than ascending phlebography combined with ultrasound to improve treatment efficacy for recurrent varices. These results should be verified by an future study with more patients and long-term follow-up.


Assuntos
Úlcera , Varizes , Feminino , Humanos , Flebografia/métodos , Recidiva Local de Neoplasia , Varizes/diagnóstico por imagem , Varizes/cirurgia , Resultado do Tratamento , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção
7.
Clin Radiol ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38849236

RESUMO

AIMS: The objective of our study was to establish and verify a novel combined model based on multiparameter magnetic resonance imaging (MRI) radiomics and clinical features to distinguish intraspinal schwannomas from meningiomas. MATERIALS AND METHODS: This research analyzed the preoperative magnetic resonance (MR) images and clinical characteristics of 209 patients with intraspinal tumors who received tumor resection at three institutions. 159 individuals from institutions 1 and 2 were randomly assigned into a training group (n=111) and a test group (n=48) in a 7-3 ratio. A nomogram was constructed using the training cohort and was internally and externally verified in the test cohort and an independent validation cohort (n=50). Model performance was assessed utilizing the area under the curve (AUC) of receiver operating characteristics (ROC), decision curve analysis (DCA), and calibration curves. RESULTS: The nomogram exhibited superior predictive efficacy in distinguishing between spinal schwannomas and meningiomas when compared to both the radiomics model and the clinical model. The nomogram yielded AUCs of 0.994, 0.962, and 0.949 in the training, test, and external validation cohorts, respectively, indicating its exceptional differentiating ability. The DCAs demonstrated that the nomogram yielded the best net benefit. The calibration curves indicated that the nomogram got good agreement between the predicted and the actual observation. CONCLUSION: This research suggests that the nomogram incorporating clinical and radiomic features may be an effective auxiliary tool for distinguishing between intraspinal schwannomas and meningiomas, and has important clinical significance for clinical decision-making and prognosis prediction.

8.
Climacteric ; 27(3): 305-313, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38275172

RESUMO

OBJECTIVES: This study aimed to investigate the effect and the mechanism of recombinant human fibroblast growth factor 18 (rhFGF18) on postmenopausal osteoporosis. METHODS: The effect of rhFGF18 on the proliferation and apoptosis of osteoblasts and the mechanism underlying such an effect was evaluated using an oxidative stress model of the MC3T3-E1 cell line. Furthermore, ovariectomy was performed on ICR mice to imitate estrogen-deficiency postmenopausal osteoporosis. Bone metabolism and bone morphological parameters in the ovariectomized (OVX) mice were evaluated. RESULTS: The results obtained from the cell model showed that FGF18 promoted MC3T3-E1 cell proliferation by activating the extracellular signal-regulated kinase (ERK) and p38 instead of c-Jun N-terminal kinase (JNK). FGF18 also prevented cells from damage inflicted by oxidative stress via inhibition of apoptosis. After FGF18 administration, the expression level of anti-apoptotic protein Bcl-2 in the mice was upregulated, whereas those of the pro-apoptotic proteins Bax and caspase-3 were downregulated. Administering FGF18 also improved bone metabolism and bone morphological parameters in OVX mice. CONCLUSIONS: FGF18 could effectively prevent bone loss in OVX mice by enhancing osteoblastogenesis and protecting osteoblasts from oxidative stress-induced apoptosis.


Assuntos
Apoptose , Proliferação de Células , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos , Osteoblastos , Osteoporose Pós-Menopausa , Ovariectomia , Estresse Oxidativo , Proteínas Recombinantes , Animais , Fatores de Crescimento de Fibroblastos/farmacologia , Camundongos , Feminino , Apoptose/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Osteoblastos/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos , Osteoporose Pós-Menopausa/prevenção & controle , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos ICR , Linhagem Celular
9.
Public Health ; 227: 282-290, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38238130

RESUMO

OBJECTIVES: To assess the prevalence, all-cause mortality and determinants of advanced HIV disease (AHD) or severe immunosuppression (SIS) in the rural-urban communities of Southwestern China. STUDY DESIGN: Retrospective cohort study. METHOD: Data on HIV/AIDS cases reported in 2005-20 were collected from Case Report System. A binary logistic regression model assessed the risk factors of AHD/SIS prevalence. Survival curves across rural-urban regions were compared using Kaplan-Meier estimates and log-rank tests. Determinants of all-cause mortality were identified using the Cox proportional hazard model. RESULTS: Among 14,533 newly diagnosed HIV/AIDS patients, 7497 (51.6%) presented with AHD and 2564 (17.6%) with SIS. Compared with urban patients, rural patients had a higher prevalence of AHD (56.7% vs 40.7%) and SIS (20.1% vs 12.4%), all-cause mortality (AHD 12.3 vs 5.6, SIS 16.3 vs 5.5, per 100 person-years). Their 5-year survival probability (AHD 59.5% vs 77.1%; SIS 54.4% vs 76.3%) and mean survival time (AHD 106.5 vs 140.6 months, SIS 95.3 vs 144.2 months, p < 0.0001) were lower. Rural patients had an increased risk of SIS prevalence (adjusted odds ratios 1.45, 95% confidence interval [CI] 1.28-1.64; p < 0.0001) and mortality of the total cohort (adjusted hazard ratios 1.41, 95% CI 1.29-1.55; p < 0.0001), AHD cohort (1.38, 1.24-1.54; p < 0.0001), and SIS cohort (1.49, 1.23-1.81; p < 0.0001). CONCLUSIONS: A high prevalence of AHD/SIS was a severe phenomenon that caused high mortality in rural areas. A regional point-of-care strategy targeting AHD/SIS detection and management is essential for reducing the mortality risk.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Estudos Retrospectivos , Infecções por HIV/epidemiologia , Infecções por HIV/diagnóstico , Fatores de Risco , Modelos de Riscos Proporcionais
10.
Br Poult Sci ; 65(1): 44-51, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37772759

RESUMO

1. The bioflavonoid quercetin is a biologically active component, but its functional regulation of granulosa cells (GCs) during chicken follicular development is little studied. To investigate the effect of quercetin on follicular development in laying hens, an in vitro study was conducted on granulosa cells from hierarchical follicles treated with quercetin.2. The effect of quercetin on cell activity, proliferation and apoptosis of granulosa cells was detected by CCK-8, EdU and apoptosis assays. The effect on progesterone secretion from granulosa cells was investigated by enzyme-linked immunosorbent assay (ELISA). Expression of proliferating cell nuclear antigen (PCNA) mRNA and oestrogen receptors (ERs), as well as the expression of steroid acute regulatory protein (StAR), cytochrome P450 cholesterol side chain cleavage enzyme (P450scc) and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) mRNA during progesterone synthesis, were measured by real-time quantitative polymerase chain reaction (RT-qPCR). PCNA, StAR and CYP11A1 protein expression levels were detected using Western blotting (WB).3. The results showed that treatment with quercetin in granulosa cells significantly enhanced cell vitality and proliferation, reduced apoptosis and promoted the expression of gene and protein levels of PCNA. The levels of progesterone secretion increased significantly following quercetin treatment, as did the expression levels of StAR and CYP11A1 using the Western Blot (WB) method.4. The mRNA expression levels of ERα were significantly upregulated in the 100 ng/ml and 1000 ng/ml quercetin-treated groups, while there was no significant difference in expression levels of ERß mRNA.


Assuntos
Galinhas , Progesterona , Feminino , Animais , Progesterona/metabolismo , Progesterona/farmacologia , Galinhas/genética , Quercetina/farmacologia , Quercetina/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Antígeno Nuclear de Célula em Proliferação/farmacologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Células da Granulosa/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Br Poult Sci ; : 1-8, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727603

RESUMO

1. The accumulation of excessive fat plays a role in the development of non-alcoholic fatty liver disease (NAFLD) and phytogenic feed additives have the potential to ameliorate this. This study involved the isolation and culture of primary hepatocytes from chicken embryos to establish a model of hepatic steatosis induced by oleic acid/dexamethasone (OA/DEX). Lipid accumulation and cell viability were assessed using Nile Red staining, Oil Red O staining and cell count Kit -8 (CCK8) following treatment with varying concentrations of quercetin (Que). The potential mechanism by which Que exerts its effects was preliminarily investigated.2. The results indicated that OA effectively treated lipid accumulation in hepatocytes. There was no notable variance in cell proliferation between the normal and OA/DEX groups when subjected to Que treatment at concentrations of 1000 ng/ml and 10 000 ng/ml. Triglycerides and cholesterol (low and high density) decreased with Que treatment, with the most substantial reduction observed at 10 000 ng/ml.3. Gene expression levels decreased to levels similar to those in the control groups. Western blot data demonstrated that sterol regulatory element-binding protein 1 (SREBP-1) protein expression correlated with its mRNA expression level. Que mitigated lipid accumulation through the alpha serine/threonine protein kinase (AKT) and extracellular signal-regulated kinase (ERK) pathways. Expression levels of lipid-related genes (APOB, PPARα, CYP3A5 and SREBP-1) decreased to levels similar to the control groups. Western blot data demonstrated that the SREBP-1 protein expression correlated with its mRNA expression level.4. Supplementation with Que ameliorated lipid accumulation through AKT and ERK signalling pathway in OA/DEX-induced high-fat hepatocytes.

12.
Zhonghua Zhong Liu Za Zhi ; 46(7): 663-675, 2024 Jul 23.
Artigo em Zh | MEDLINE | ID: mdl-39034802

RESUMO

Objective: To investigate the influence of circ_BACH2 on the malignant biological behavior of papillary thyroid cancer and its molecular mechanism. Methods: Cancer tissues and paracancer tissues of 51 patients with papillary thyroid carcinoma from the Fourth Central Hospital of Tianjin between 2017 and 2019 were collected. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect the expressions of circ_BACH2, miR-370-3p and G protein coupled receptor kinase interacting factor 1 (GIT1) mRNA in tissues and cells; flow cytometry to detect cell apoptosis and cell cycle; plate clone formation experiment to detect the number of cell clones; cell counting kit 8 (CCK-8) to detect cell proliferation; Transwell array to detect cell migration and invasion; western blot to detect protein expressions; dual luciferase report experiment to detect the targeting relationship between circ_BACH2, miR-370-3p and GIT1; the nude mouse tumor formation experiment to detect the effect of circ_BACH2 on tumors in mice. Results: Compared with adjacent tissues, the expressions of circ_BACH2 and GIT1 in papillary thyroid cancer tissues was increased, while the expression of miR-370-3p was decreased. Compared with Nthy-ori3-1 cells, the expressions of circ_BACH2 in papillary thyroid cancer cells TPC-1 and SW579 were increased, the mRNA and protein levels of GIT1 were increased, miR-370-3p expression was decreased. The expression level of GIT1 mRNA was negatively correlated with that of miR-370-3p (r=-0.634), and the expression level of circ_BACH2 was positively correlated with that of GIT1 (r=0.635). The expression level of circ_BACH2 was negatively correlated with that of miR-370-3p (r=-0.394, P<0.05). Circ_BACH2 and miR-370-3p has a binding site at the 3' UTR of GIT1. After knocking down circ_BACH2, the proportion of G0/G1 cells in papillary thyroid cancer cells TPC-1 and SW579 was increased, the proportion of S-phase cells was decreased and the proportion of G2/M-phase cells did not change significantly. The cell absorbance value was lower than that in si-NC group. The number of cell clone formation was decreased (43±5 vs 100±6, 54±8 vs 100±9); the cell apoptosis rate was increased [(19.60±2.40)% vs (4.30±0.20)%, (18.10±2.10)% vs (5.10±0.23)%]; cell migration number was decreased (61±7 vs 134±15, 58±6 vs 112±11), the invasion number was also decreased (45±6 vs 113±11, 47±4 vs 92±9); the expressions of Snail and Twist1 were decreased, and the expression of E-cadherin was increased (P<0.000). Inhibition of miR-370-3p expression reversed the effect of circ_BACH2 knockdown on proliferation, migration, invasion and apoptosis of thyroid papillary cancer cells. Overexpression of GIT1 reversed the effects of overexpression of miR-370-3p on proliferation, migration, invasion and apoptosis of thyroid papillary cancer cells. Mice injected with TPC-1 cells stably transfected with sh-circ_BACH2 showed a reduction in tumor volume [(535±91) mm3 vs (857±114) mm3] after 35 days of culture; tumor weight was decreased [(0.62±0.13) mg vs (1.06±0.15) mg, P<0.05]; the expressions of circ_BACH2 and GIT1 were decreased, and the expression of miR-370-3p was increased in nude mouse tumor tissue. Conclusion: Silencing circ_BACH2 may inhibit the proliferation, migration and invasion of papillary thyroid cancer cells in vitro, promote cell apoptosis, and inhibit tumor growth in vivo through targeted regulation of miR-370-3p/GIT1.


Assuntos
Proliferação de Células , Camundongos Nus , MicroRNAs , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , MicroRNAs/metabolismo , MicroRNAs/genética , Humanos , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/patologia , Animais , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Camundongos , Linhagem Celular Tumoral , Apoptose , RNA Circular/metabolismo , RNA Circular/genética , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Ciclo Celular , RNA Mensageiro/metabolismo , RNA Mensageiro/genética
13.
Zhonghua Yi Xue Za Zhi ; 104(9): 695-703, 2024 Mar 05.
Artigo em Zh | MEDLINE | ID: mdl-38418169

RESUMO

Objective: To explore the mechanism of cross-linked hyaluronic acid-dexamethasone hydrogel (cHA-Dex) in inhibiting chondrocyte apoptosis and alleviating early post-traumatic osteoarthritis (PTOA). Methods: To generate PTOA model, anterior cruciate ligament transection (ACLT)was performed on SD rats (n=70), and the sham surgery group (n=70) was set as control. The changes in inflammatory indicators such as interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), matrix metalloproteinase-3 (MMP-3), and matrix metalloproteinase-13 (MMP-13) in the joint lavage fluid were measured at different time points (1-14 days, 5 rats at each time point) after surgery. The cHA-Dex (0.5 mg/ml) hydrogel (experimental group, n=70) and ordinary low-molecular-weight hyaluronic acid (HA) hydrogel premixed with Dex, that was, HA-Dex (0.5 mg/ml) hydrogel (control group, n=70) were injected into the joint cavity of PTOA rats, and the release amount and cumulative release amount of Dex in the joint fluid of rats at each time point(1-14 days, 5 rats at each time point) were detected to reveal the release mechanism of cHA-Dex hydrogel. The cartilage of knee joint of patients with osteoarthritis (OA) who underwent knee arthroplasty in the Second Hospital of Shanxi Medical University from January 2020 to December 2022 was taken for in vitro tissue block culture (Outbridge score=1 or 2,n=18). After the cartilage tissue block was treated with cHA-Dex hydrogel premixed with 0.1, 0.2, and 0.5 mg/ml Dex, the mRNA expression levels of IL-1ß, IL-6, TNF-α, MMP-3, and MMP-13 in the articular cartilage tissue block were detected. OA chondrocytes were isolated from cartilage samples using enzymatic hydrolysis and cultured in vitro (n=18). Chondrocytes were divided into 4 groups: saline, cHA hydrogel, Dex (0.5 mg/ml), and cHA-Dex (0.5 mg/ml) hydrogel group. The effects of different interventions on chondrocyte proliferation and apoptosis were tested. Results: The Osteoarthritis Research Society International (OARSI) score of safranine O-solid green staining in PTOA group was 3.34±0.35, and it was 1.17±0.21 in Sham group(P=0.010). The Meachim score of knee joint osteophytes in PTOA rats was significantly higher than that in the Sham group (2.66±0.41 vs 0.22±0.17, P=0.010), indicating PTOA model in rat was established successfully. The cHA-Dex hydrogel, which corresponded to the peak changes of inflammatory factors in the joints of PTOA rats in the early stage, was also released in the early stage and sustained-released in the late stage. After the OA articular cartilage tissue block was treated with cHA-Dex hydrogel premixed with 0.1, 0.2, and 0.5 mg/ml Dex, the mRNA expression levels of IL-1 ß, IL-6, TNF-α, MMP-3, and MMP-13 in the tissue block were reduced significantly (all P<0.05) and in a dose-dependent manner. Compared with Dex (0.5 mg/ml) alone group, the apoptosis rate of cHA-Dex (0.5 mg/ml) hydrogel group was significantly reduced (0.60±0.07 vs 6.63±0.98, P=0.010).Compared with the normal saline or the cHA hydrogel alone group, the cHA-Dex (0.5 mg/ml) hydrogel group had significant cell proliferation, and the difference at each time point were all significant statistically (all P<0.05). Conclusion: For the early inflammation of PTOA, cHA-Dex hydrogel can not only inhibit cartilage inflammation, but also reverse the increased apoptosis and decreased proliferation rate of chondrocytes caused by Dex, and finally alleviate the progress of PTOA by releasing Dex.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Ratos , Animais , Ácido Hialurônico/farmacologia , Metaloproteinase 3 da Matriz/farmacologia , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 13 da Matriz/farmacologia , Interleucina-6 , Fator de Necrose Tumoral alfa/metabolismo , Ratos Sprague-Dawley , Osteoartrite/metabolismo , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Inflamação , Condrócitos , Dexametasona/farmacologia , Hidrogéis/farmacologia , RNA Mensageiro
14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(2): 248-253, 2024 Feb 06.
Artigo em Zh | MEDLINE | ID: mdl-38387958

RESUMO

By conducting retrospective analysis, this study aim to investigate the resistance mechanism of quinolones in non-typhoidal Salmonella (NTS). A total of 105 strains of NTS isolated from clinical specimens from the Fifth Affiliated Hospital of Southern Medical University from May 2020 to February 2021 were used as research objects. VITEK2 Compact automatic identification drug sensitivity analysis system and serological test were used to identify the strains. The sensitivity of the strains to ciprofloxacin, levofloxacin and nalidixic acid was detected by AGAR dilution method. The whole genome of 105 strains of NTS was sequenced. Abricate and other softwares were used to analyze drug-resistant genes, including plasmid-mediated quinolone resistance gene (PMQR) and Quinolone resistance determination region (QRDR). Serotypes and ST types were analyzed using SISTR and MLST, and phylogenetic trees were constructed. The results showed that the NTS isolated in this region were mainly ST34 Salmonella typhimurium (53.3%). The drug sensitivity results showed that the drug resistance rates of NTS to ciprofloxacin, levofloxacin and nalidixic acid were 30.4%, 1.9% and 22.0%, respectively, and the intermediate rates of ciprofloxacin and levofloxacin were 27.6% and 54.2%.A total of 46 (74.2%) of the 62 quinolone non-susceptible strains carried the PMQR gene, mainly qnrS1 (80.4%), followed by aac(6')-Ib-cr(15.2%); there were 14 NTS and 8 NTS had gyrA and parC gene mutations, respectively. The gyrA was mutations at the amino acid position 87, Asp87Tyr, Asp87Asn, Asp87Gly, and Thr57Ser mutations were detected in parC. In conclusion, this study found that NTS had relatively high resistance to quinolones, carrying qnrS1 gene mainly resulted in decreased sensitivity of NTS to ciprofloxacin and levofloxacin, and gyrA:87 mutation mainly resulted in NTS resistance to Nalidixic acid; Salmonella typhimurium in clinical isolates showed clonal transmission and required further epidemiological surveillance.


Assuntos
Quinolonas , Humanos , Quinolonas/farmacologia , Ácido Nalidíxico/farmacologia , Levofloxacino/farmacologia , Filogenia , Tipagem de Sequências Multilocus , Estudos Retrospectivos , DNA Girase/genética , Salmonella , Ciprofloxacina , Plasmídeos , Mutação , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética
15.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 823-829, 2024 Jun 06.
Artigo em Zh | MEDLINE | ID: mdl-38955729

RESUMO

This study was to investigate the relationship between spring pollen distribution concentration, species and the detection results of air-borne pollen allergens in Taiyuan City, Shanxi Province during March to May 2022 and March to May 2023.A retrospective study was conducted in the Otorhinolaryngology Head and Neck Surgery Clinic of the First Hospital of Shanxi Medical University.Pollen particles will be monitored by gravity sedimentation method on the roof of the outpatient department of the First Hospital of Shanxi Medical University in downtown Taiyuan from March to May 2022-2023, and pollen species and quantity will be observed and recorded under an optical microscope.The air-borne pollen allergen detection results of all allergic rhinitis patients in the otolaryngology Head and Neck surgery Department of the First Hospital of Shanxi Medical University were extracted from the relevant outpatient system. SPSS software and Pearson correlation analysis were used to compare the correlation between the allergens and the dominant air-borne pollen monitoring results. Results are as follows: (1)A total of 18 species of spring pollen in Taiyuan City were monitored in 2022-2023, with 101 177.5 grains, and the dominant airborne pollen was poplar (16.69%) and pine (29.06%) pollen. The pollen of poplar (11.96%), elm (7.89%) and cypress (8.68%) were dominant in early spring; Pine (25.16%) pollen predominated in late spring. The two peaks of pollen dispersal in Taiyuan were in late March (15 479 grains) and early and mid May (15 094/15 343 grains).(2) The positive rates of allergens in serum specific IgE detection were: wormwood (46%, 248/541 cases), tree combination (26%, 143/541 cases), ragweed (19%, 101/541 cases), humulus scandens (9%, 49/541 cases).(3)There was a linear positive correlation between the positive rate of air-borne pollen allergens in allergic rhinitis patients in the Department of Otolaryngology Head and Neck Surgery in the First Hospital of Shanxi Medical University and the dominant air-borne pollen concentration in the same period (P<0.05, r=0.999). In conclusion, two spring pollen dispersal peaks were formed in late March and early to mid May in Taiyuan City, and the dominant air-borne pollens were poplar and pine pollens. The positive rate of air borne pollen allergen sIgE showed that wormwood allergy was the highest.There was a positive correlation between the concentration of air-borne pollen and the positive rate of air-borne pollen allergens in patients with allergic rhinitis in the Department of otorhinolaryngology and head and neck surgery in Taiyuan in 2022 and 2023.The monitoring of pollen distribution in spring can provide an important scientific basis for clinical workers to formulate prevention and treatment plans for patients with allergic rhinitis in the season, and provide data reference for the epidemiological investigation of allergic diseases in Taiyuan in the future.


Assuntos
Alérgenos , Pólen , Humanos , China , Estudos Retrospectivos , Imunoglobulina E/sangue , Estações do Ano , Rinite Alérgica , Rinite Alérgica Sazonal
16.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(1): 87-90, 2024 Jan 12.
Artigo em Zh | MEDLINE | ID: mdl-38062702

RESUMO

Acute respiratory distress syndrome (ARDS) is a collection of clinical syndromes characterized by a variety of heterogeneous causes. It includes diffuse lung diseases of various etiologies that ultimately lead to refractory hypoxia and severe acute respiratory failure. Despite advances in research and treatment of ARDS, its incidence and mortality continue to pose significant challenges in clinical practice. Since its inception in 1967, the definition of ARDS has undergone several revisions that have generated controversy and influenced the implementation of diagnostic and treatment strategies. At present, ARDS remains a formidable obstacle to both diagnosis and treatment. This article undertakes a comprehensive review of the evolution of ARDS definitions, examines the current diagnostic paradigm, and explores its far-reaching consequences. Our aim is to identify research directions, both in the realm of basic science and clinical practice, that are consistent with the nature of this complex disorder.


Assuntos
Síndrome do Desconforto Respiratório , Humanos , Síndrome do Desconforto Respiratório/terapia , Respiração Artificial/efeitos adversos , Respiração com Pressão Positiva , Hipóxia , Fatores de Risco
17.
Phys Rev Lett ; 131(15): 151001, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897763

RESUMO

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

18.
BMC Neurol ; 23(1): 38, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36694119

RESUMO

BACKGROUND: Parkinsonism after ventriculoperitoneal shunt in patients with hydrocephalus is a rare and profound complication that is often misdiagnosed, causing treatment to be delayed. To date, the characteristics of this disease have not been well described and summarized. Here, we report a rare case of parkinsonism after ventriculoperitoneal shunt; symptoms were aggravated by antipsychotic drugs but showed a good response to Madopar. Such cases have rarely been reported previously. CASE PRESENTATION: A 44-year-old man presented with parkinsonism, bilateral pyramidal tract signs, and oculomotor impairment four years after a successful ventriculoperitoneal shunt for idiopathic aqueduct stenosis resulting in obstructive hydrocephalus. Brain magnetic resonance imaging and computed tomography showed fluctuations in the lateral ventricle and the third ventricle without any intervention. The patient's condition was aggravated by antipsychotic drugs but showed a good response to Madopar. CONCLUSION: This observation suggests that parkinsonism in this patient was caused by reversible dysfunction of the presynaptic nigrostriatal dopaminergic pathway due to fluctuations in the lateral ventricle, representing the first hit to the dopaminergic signalling pathway, and antipsychotic drugs had an antagonistic effect on dopamine D2 receptors, representing the second hit. In addition, we summarize the pathophysiological mechanisms, clinical manifestations, treatments, and prognoses of this complication in 38 patients who met the inclusion criteria in 24 previous studies to increase neurologists' understanding of the disease.


Assuntos
Antipsicóticos , Hidrocefalia , Transtornos Parkinsonianos , Masculino , Humanos , Adulto , Derivação Ventriculoperitoneal/efeitos adversos , Transtornos Parkinsonianos/etiologia , Transtornos Parkinsonianos/complicações , Hidrocefalia/cirurgia , Hidrocefalia/etiologia , Dopamina
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