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1.
J Cardiothorac Surg ; 19(1): 171, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566106

RESUMEN

BACKGROUND: Acute Type A aortic dissection (ATAAD) is a life-threatening cardiovascular disease associated with high mortality rates, where surgical intervention remains the primary life-saving treatment. However, the mortality rate for ATAAD operations continues to be alarmingly high. To address this critical issue, our study aimed to assess the correlation between preoperative laboratory examination, clinical imaging data, and postoperative mortality in ATAAD patients. Additionally, we sought to establish a reliable prediction model for evaluating the risk of postoperative death. METHODS: In this study, a total of 384 patients with acute type A aortic dissection (ATAAD) who were admitted to the emergency department for surgical treatment were included. Based on preoperative laboratory examination and clinical imaging data of ATAAD patients, logistic analysis was used to obtain independent risk factors for postoperative in-hospital death. The survival prediction model was based on cox regression analysis and displayed as a nomogram. RESULTS: Logistic analysis identified several independent risk factors for postoperative in-hospital death, including Marfan syndrome, previous cardiac surgery history, previous renal dialysis history, direct bilirubin, serum phosphorus, D-dimer, white blood cell, multiple aortic ruptures and age. A survival prediction model based on cox regression analysis was established and presented as a nomogram. The model exhibited good discrimination and significantly improved the prediction of death risk in ATAAD patients. CONCLUSIONS: In this study, we developed a novel survival prediction model for acute type A aortic dissection based on preoperative clinical features. The model demonstrated good discriminatory power and improved accuracy in predicting the risk of death in ATAAD patients undergoing open surgery.


Asunto(s)
Disección Aórtica , Síndrome de Marfan , Humanos , Mortalidad Hospitalaria , Estudios Retrospectivos , Disección Aórtica/cirugía , Factores de Riesgo
2.
Sci Rep ; 14(1): 7845, 2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570622

RESUMEN

Temporary neurological dysfunction (TND), a common complication following surgical repair of Type A Aortic Dissection (TAAD), is closely associated with increased mortality and long-term cognitive impairment. Currently, effective treatment options for TND remain elusive. Therefore, we sought to investigate the potential of postoperative relative band power (RBP) in predicting the occurrence of postoperative TND, with the aim of identifying high-risk patients prior to the onset of TND. We conducted a prospective observational study between February and December 2022, involving 165 patients who underwent surgical repair for TAAD at our institution. Bedside Quantitative electroencephalography (QEEG) was utilized to monitor the post-operative brain electrical activity of each participant, recording changes in RBP (RBP Delta, RBP Theta, RBP Beta and RBP Alpha), and analyzing their correlation with TND. Univariate and multivariate analyses were employed to identify independent risk factors for TND. Subsequently, line graphs were generated to estimate the incidence of TND. The primary outcome of interest was the development of TND, while secondary outcomes included intensive care unit (ICU) admission and length of hospital stay. A total of 165 patients were included in the study, among whom 68 (41.2%) experienced TND. To further investigate the independent risk factors for postoperative TND, we conducted both univariate and multivariate logistic regression analyses on all variables. In the univariate regression analysis, we identified age (Odds Ratio [OR], 1.025; 95% CI, 1.002-1.049), age ≥ 60 years (OR, 2.588; 95% CI, 1.250-5.475), hemopericardium (OR, 2.767; 95% CI, 1.150-7.009), cardiopulmonary bypass (CPB) (OR, 1.007; 95% CI, 1.001-1.014), RBP Delta (OR, 1.047; 95% CI, 1.020-1.077), RBP Alpha (OR, 0.853; 95% CI, 0.794-0.907), and Beta (OR, 0.755; 95% CI, 0.649-0.855) as independent risk factors for postoperative TND. Further multivariate regression analyses, we discovered that CPB time ≥ 180 min (OR, 1.021; 95% CI, 1.011-1.032), RBP Delta (OR, 1.168; 95% CI, 1.105-1.245), and RBP Theta (OR, 1.227; 95% CI, 1.135-1.342) emerged as independent risk factors. TND patients had significantly longer ICU stays (p < 0.001), and hospital stays (p = 0.002). We obtained the simplest predictive model for TND, consisting of three variables (CPB time ≥ 180 min, RBP Delta, RBP Theta, upon which we constructed column charts. The areas under the receiver operating characteristic (AUROC) were 0.821 (0.755, 0.887). Our study demonstrates that postoperative RBP monitoring can detect changes in brain function in patients with TAAD during the perioperative period, providing clinicians with an effective predictive method that can help improve postoperative TND in TAAD patients. These findings have important implications for improving clinical care in this population.Trial registration ChiCTR2200055980. Registered 30th Jan. 2022. This trial was registered before the first participant was enrolled.


Asunto(s)
Disección Aórtica , Azidas , Desoxiglucosa/análogos & derivados , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Disección Aórtica/cirugía , Resultado del Tratamiento , Factores de Riesgo , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología
3.
J Cardiothorac Surg ; 19(1): 138, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504265

RESUMEN

BACKGROUND: Postoperative hyper-inflammation is a frequent event in patients with acute Stanford type A aortic dissection (ATAAD) after surgical repair. This study's objective was to determine which inflammatory biomarkers could be used to make a better formula for identifying postoperative hyper-inflammation, and which risk factors were associated with hyper-inflammation. METHODS: A total of 405 patients were enrolled in this study from October 1, 2020 to April 1, 2023. Of these patients, 124 exhibited poor outcomes. In order to investigate the optimal cut-off values for poor outcomes, logistic and receiver operating characteristic analyses were performed on the following parameters on the first postoperative day: procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6), and systemic immune-inflammation index (SII). These cut-off points were used to separate the patients into hyper-inflammatory (n = 52) and control (n = 353) groups. Finally, the logistic were used to find the risk factors of hyper-inflammatory. RESULTS: PCT, CRP, IL-6, and SII were independent risk factors of poor outcomes in the multivariate logistic model. Cut-off points of these biomarkers were 2.18 ng/ml, 49.76 mg/L, 301.88 pg/ml, 2509.96 × 109/L respectively. These points were used to define postoperative hyper-inflammation (OR 2.97, 95% CI 1.35-6.53, P < 0.01). Cardiopulmonary bypass (CPB) > 180 min, and deep hypothermia circulatory arrest (DHCA) > 40 min were the independent risk factors for hyper-inflammation. CONCLUSIONS: PCT > 2.18, CRP > 49.76, IL-6 > 301.88, and SII < 2509.96 could be used to define postoperative hyper-inflammation which increased mortality and morbidity in patients after ATAAD surgery. Based on these findings, we found that CPB > 180 min and DHCA > 40 min were separate risk factors for postoperative hyper-inflammation.


Asunto(s)
Disección Aórtica , Interleucina-6 , Humanos , Disección Aórtica/cirugía , Inflamación , Biomarcadores , Factores de Riesgo , Polipéptido alfa Relacionado con Calcitonina , Proteína C-Reactiva , Estudios Retrospectivos
4.
Sci Total Environ ; 920: 171006, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38369137

RESUMEN

Understanding the patterns and controls regulating nitrogen (N) transformation and its response to N enrichment is critical to re-evaluating soil N limitation or availability and its environmental consequences. Nevertheless, how climatic conditions affect nitrate dynamics and the response of gross N cycling rates to N enrichment in forest soils is still only rudimentarily known. Through collecting and analyzing 4426-single and 769-paired observations from 231 15N labeling studies, we found that nitrification capacity [the ratio of gross autotrophic nitrification (GAN) to gross N mineralization (GNM)] was significantly lower in tropical/subtropical (19%) than in temperate (68%) forest soils, mainly due to the higher GNM and lower GAN in tropical/subtropical regions resulting from low C/N ratio and high precipitation, respectively. However, nitrate retention capacity [the ratio of dissimilatory nitrate reduction to ammonium (DNRA) plus gross nitrate immobilization (INO3) to gross nitrification] was significantly higher in tropical/subtropical (86%) than in temperate (54%) forest soils, mainly due to the higher precipitation and GNM of tropical/subtropical regions, which stimulated DNRA and INO3. As a result, the ratio of GAN to ammonium immobilization (INH4) was significantly higher in temperate than in tropical/subtropical soils. Climatic rather than edaphic factors control heterotrophic nitrification rate (GHN) in forest soils. GHN significantly increased with increasing temperature in temperate regions and with decreasing precipitation in tropical/subtropical regions. In temperate forest soils, gross N transformation rates were insensitive to N enrichment. In tropical/subtropical forests, however, N enrichment significantly stimulated GNM, GAN and GAN to INH4 ratio, but inhibited INH4 and INO3 due to reduced microbial biomass and pH. We propose that temperate forest soils have higher nitrification capacity and lower nitrate retention capacity, implying a higher potential risk of N losses. However, tropical/subtropical forest systems shift from a conservative to a leaky N-cycling system in response to N enrichment.


Asunto(s)
Compuestos de Amonio , Nitrógeno , Nitrógeno/análisis , Nitratos/análisis , Suelo , Bosques
7.
Infection ; 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38265608

RESUMEN

BACKGROUND AND PURPOSE: The need for dose adjustment of caspofungin in patients with hepatic impairment is controversial, especially for those with Child-Pugh B or C cirrhosis. The purpose of this study was to investigate the safety and efficacy of standard-dose caspofungin administration in Child-Pugh B and C cirrhotic patients in a real-world clinical setting. PATIENTS AND METHODS: The electronic medical records of 258 cirrhotic patients, including 67 Child-Pugh B patients and 191 Child-Pugh C patients, who were treated with standard-dose of caspofungin at the Second Affiliated Hospital of Chongqing Medical University, China, from March 2018 to June 2023 were reviewed retrospectively. The white blood cells (WBC), hepatic, renal and coagulation function results before administration and post administration on days 7, 14 and 21 were collected, and the efficacy was assessed in all patients at the end of caspofungin therapy. RESULTS: Favorable responses were achieved in 137 (53.1%) patients while 34 (13.2%) patients died. We observed that some patients experienced an increase of prothrombin time (PT) or international normalized ratio (INR), or a decrease of WBC, but no exacerbation of hepatic or renal dysfunction were identified and no patient required dose interruption or adjustment because of an adverse drug reaction during treatment with caspofungin. CONCLUSIONS: Standard-dose of caspofungin can be safely and effectively used in patients with Child-Pugh B or C cirrhosis, and we appealed to re-assess the most suitable dosing regimen in this population to avoid a potential subtherapeutic exposure.

8.
Nat Commun ; 14(1): 5438, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37673863

RESUMEN

T-box riboswitches are multi-domain noncoding RNAs that surveil individual amino acid availabilities in most Gram-positive bacteria. T-boxes directly bind specific tRNAs, query their aminoacylation status to detect starvation, and feedback control the transcription or translation of downstream amino-acid metabolic genes. Most T-boxes rapidly recruit their cognate tRNA ligands through an intricate three-way stem I-stem II-tRNA interaction, whose establishment is not understood. Using single-molecule FRET, SAXS, and time-resolved fluorescence, we find that the free T-box RNA assumes a broad distribution of open, semi-open, and closed conformations that only slowly interconvert. tRNA directly binds all three conformers with distinct kinetics, triggers nearly instantaneous collapses of the open conformations, and returns the T-box RNA to their pre-binding conformations upon dissociation. This scissors-like dynamic behavior is enabled by a hinge-like pseudoknot domain which poises the T-box for rapid tRNA-induced domain closure. This study reveals tRNA-chaperoned folding of flexible, multi-domain mRNAs through a Venus flytrap-like mechanism.


Asunto(s)
Pliegue del ARN , Riboswitch , Dispersión del Ángulo Pequeño , Difracción de Rayos X , ARN , Riboswitch/genética , Aminoácidos , Chaperonas Moleculares
9.
Sci Adv ; 9(39): eadi8606, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37756408

RESUMEN

Graft-host mechanical mismatch has been a longstanding issue in clinical applications of synthetic scaffolds for soft tissue regeneration. Although numerous efforts have been devoted to resolve this grand challenge, the regenerative performance of existing synthetic scaffolds remains limited by slow tissue growth (comparing to autograft) and mechanical failures. We demonstrate a class of rationally designed flexible network scaffolds that can precisely replicate nonlinear mechanical responses of soft tissues and enhance tissue regeneration via reduced graft-host mechanical mismatch. Such flexible network scaffold includes a tubular network frame containing inversely engineered curved microstructures to produce desired mechanical properties, with an electrospun ultrathin film wrapped around the network to offer a proper microenvironment for cell growth. Using rat models with sciatic nerve defects or Achilles tendon injuries, our network scaffolds show regenerative performances evidently superior to that of clinically approved electrospun conduit scaffolds and achieve similar outcomes to autologous nerve transplantation in prevention of target organ atrophy and recovery of static sciatic index.


Asunto(s)
Biomimética , Películas Cinematográficas , Animales , Ratas , Proliferación Celular , Atrofia , Ciclo Celular
10.
Nucleic Acids Res ; 51(18): 9952-9960, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37534568

RESUMEN

RNA conformational heterogeneity often hampers its high-resolution structure determination, especially for large and flexible RNAs devoid of stabilizing proteins or ligands. The adenosylcobalamin riboswitch exhibits heterogeneous conformations under 1 mM Mg2+ concentration and ligand binding reduces conformational flexibility. Among all conformers, we determined one apo (5.3 Å) and four holo cryo-electron microscopy structures (overall 3.0-3.5 Å, binding pocket 2.9-3.2 Å). The holo dimers exhibit global motions of helical twisting and bending around the dimer interface. A backbone comparison of the apo and holo states reveals a large structural difference in the P6 extension position. The central strand of the binding pocket, junction 6/3, changes from an 'S'- to a 'U'-shaped conformation to accommodate ligand. Furthermore, the binding pocket can partially form under 1 mM Mg2+ and fully form under 10 mM Mg2+ within the bound-like structure in the absence of ligand. Our results not only demonstrate the stabilizing ligand-induced conformational changes in and around the binding pocket but may also provide further insight into the role of the P6 extension in ligand binding and selectivity.

11.
Res Sq ; 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37425706

RESUMEN

The vast percentage of the human genome is transcribed into RNA, many of which contain various structural elements and are important for functions. RNA molecules are conformationally heterogeneous and functionally dyanmics1, even when they are structured and well-folded2, which limit the applicability of methods such as NMR, crystallography, or cryo-EM. Moreover, because of the lack of a large structure RNA database, and no clear correlation between sequence and structure, approaches like AlphaFold3 for protein structure prediction, do not apply to RNA. Therefore determining the structures of heterogeneous RNA is an unmet challenge. Here we report a novel method of determining RNA three-dimensional topological structures using deep neural networks and atomic force microscopy (AFM) images of individual RNA molecules in solution. Owing to the high signal-to-noise ratio of AFM, our method is ideal for capturing structures of individual conformationally heterogeneous RNA. We show that our method can determine 3D topological structures of any large folded RNA conformers, from ~ 200 to ~ 420 residues, the size range that most functional RNA structures or structural elements fall into. Thus our method addresses one of the major challenges in frontier RNA structural biology and may impact our fundamental understanding of RNA structure.

12.
Commun Biol ; 6(1): 712, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37433832

RESUMEN

Proper organization of intracellular assemblies is fundamental for efficient promotion of biochemical processes and optimal assembly functionality. Although advances in imaging technologies have shed light on how the centrosome is organized, how its constituent proteins are coherently architected to elicit downstream events remains poorly understood. Using multidisciplinary approaches, we showed that two long coiled-coil proteins, Cep63 and Cep152, form a heterotetrameric building block that undergoes a stepwise formation into higher molecular weight complexes, ultimately generating a cylindrical architecture around a centriole. Mutants defective in Cep63•Cep152 heterotetramer formation displayed crippled pericentriolar Cep152 organization, polo-like kinase 4 (Plk4) relocalization to the procentriole assembly site, and Plk4-mediated centriole duplication. Given that the organization of pericentriolar materials (PCM) is evolutionarily conserved, this work could serve as a model for investigating the structure and function of PCM in other species, while offering a new direction in probing the organizational defects of PCM-related human diseases.


Asunto(s)
Centriolos , Centrosoma , Proteínas Serina-Treonina Quinasas , Humanos , Ciclo Celular , Peso Molecular , Dominios Proteicos , Proteínas Serina-Treonina Quinasas/metabolismo
14.
Orthop J Sports Med ; 11(6): 23259671231172977, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37378280

RESUMEN

Background: Despite increased recognition of coexisting tibial and talar osteochondral lesions (OCLs), the risk factors influencing clinical outcomes remain unclear. Purpose: To report clinical follow-up results after arthroscopic microfracture surgery in patients with OCLs of the distal tibial plafond and talus and assess possible factors affecting these clinical outcomes. Study Design: Case series; Level of evidence, 4. Methods: A total of 40 patients with coexisting talar and tibial OCLs who underwent arthroscopic microfracture surgery were included. For analysis, the study used the American Orthopaedic Foot & Ankle Society (AOFAS) scale, Karlsson-Peterson scale, and visual analog scale (VAS) for pain for clinical evaluations on the day before surgery, 12 months after surgery, and at the last follow-up. A stepwise regression model and Spearman rank correlation were used to assess possible factors affecting these clinical outcomes. Results: The median follow-up time was 34.5 months (interquartile range [IQR], 26.5-54 months). At the final follow-up, the cohort included 40 patients (26 men and 14 women) with a mean age of 38.8 years (range, 19-60 years). The median AOFAS score increased from 57.5 (IQR, 47-65) before surgery to 88 (IQR, 83-92.5) at the final follow-up, the median Karlsson-Peterson score increased from 48 (IQR, 38.5-67) to 82 (IQR, 76-92), and the median VAS score improved from 5 (IQR, 4-6) to 1 (IQR, 0-2). All scale scores showed significant differences between the preoperative and final follow-up evaluations (P < .001). In the stepwise regression model and Spearman rank correlation analysis, the grade of tibial OCL had a significant independent effect on the final postoperative AOFAS scores of the patients (ß = -0.502, P = .001; r = -0.456, P = .003). The size of the tibial lesion also had a significant independent effect on the final postoperative Karlsson-Peterson scores of the patients (ß = -0.444, P = .004; r = -0.357, P = .024). Conclusion: Arthroscopic microfracture treatment for coexisting talar and tibial OCLs can achieve good short- to midterm clinical outcomes. The grade and size of tibial OCLs are the main risk factors affecting the prognostic functional scores of such patients.

15.
Structure ; 31(7): 848-859.e3, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37253356

RESUMEN

The thiamine pyrophosphate (TPP)-sensing riboswitch is one of the earliest discovered and most widespread riboswitches. Numerous structural studies have been reported for this riboswitch bound with various ligands. However, the ligand-free (apo) structure remains unknown. Here, we report a 3.1 Å resolution crystal structure of Escherichia coli TPP riboswitch in the apo state, which exhibits an extended, Y-shaped conformation further supported by small-angle X-ray scattering data and driven molecular dynamics simulations. The loss of ligand interactions results in helical uncoiling of P5 and disruption of the key tertiary interaction between the sensory domains. Opening of the aptamer propagates to the gene-regulatory P1 helix and generates the key conformational flexibility needed for the switching behavior. Much of the ligand-binding site at the three-way junction is unaltered, thereby maintaining a partially preformed pocket. Together, these results paint a dynamic picture of the ligand-induced conformational changes in TPP riboswitches that confer conditional gene regulation.


Asunto(s)
Riboswitch , Tiamina Pirofosfato/química , Tiamina Pirofosfato/genética , Tiamina Pirofosfato/metabolismo , Escherichia coli/metabolismo , Simulación de Dinámica Molecular , Conformación de Ácido Nucleico , Ligandos
16.
Artículo en Inglés | MEDLINE | ID: mdl-36758166

RESUMEN

Inflammation is part of the natural healing response, but persistent inflammatory events tend to contribute to pathology changes of tendon or ligament. Phenotypic switching of macrophages within the inflammatory niche is crucial for tendon healing. One viable strategy to improve the functional and biomechanical properties of ruptured tendons is to modulate the transition from inflammatory to regenerative signals during tendon regeneration at the site of injury. Here, we developed a tendon repair scaffold made of biodegradable polycaprolactone by electrospinning, which was modified to deliver Wnt3a protein and served as an implant to improve tendon healing in a rat model of Achilles tendon defect. During the in vitro study, Wnt3a protein promoted the polarization of M2 macrophages. In the in vivo experiment, Wnt3a scaffold promoted the early recruitment and counting curve of macrophages and increased the proportion of M2 macrophages. Achilles function index and mechanical properties showed that the implantation effect of the Wnt3a group was better than that of the control group. We believe that this type of scaffold can be used to repair tendon defects. This work highlights the beneficial role of local delivery of biological factors in directing inflammatory responses toward regenerative strategies in tendon healing.

17.
Nat Commun ; 14(1): 714, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36759615

RESUMEN

RNA flexibility is reflected in its heterogeneous conformation. Through direct visualization using atomic force microscopy (AFM) and the adenosylcobalamin riboswitch aptamer domain as an example, we show that a single RNA sequence folds into conformationally and architecturally heterogeneous structures under near-physiological solution conditions. Recapitulated 3D topological structures from AFM molecular surfaces reveal that all conformers share the same secondary structural elements. Only a population-weighted cohort, not any single conformer, including the crystal structure, can account for the ensemble behaviors observed by small-angle X-ray scattering (SAXS). All conformers except one are functionally active in terms of ligand binding. Our findings provide direct visual evidence that the sequence-structure relationship of RNA under physiologically relevant solution conditions is more complex than the one-to-one relationship for well-structured proteins. The direct visualization of conformational and architectural ensembles at the single-molecule level in solution may suggest new approaches to RNA structural analyses.


Asunto(s)
Proteínas , ARN , Humanos , ARN/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Proteínas/química , Conformación de Ácido Nucleico
18.
Methods Mol Biol ; 2568: 165-177, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36227568

RESUMEN

RNA-level regulation by riboswitches relies on the specific binding of small metabolites to the aptamer domain to trigger substantial conformational changes that affect transcription or translation. Although several biophysical methods have been employed to study such RNAs, the utility of any one single method is limited. Hybrid approaches, therefore, are essential to better characterize these intrinsically dynamic molecules and elucidate their regulatory mechanisms driven by ligand-induced conformational changes. This chapter outlines procedures for biochemical and biophysical characterization of RNA that employs a combination of solution-based methods: isothermal titration calorimetry (ITC), small-angle X-ray scattering (SAXS), and atomic force microscopy (AFM). Collectively, these tools provide a semi-quantitative assessment of the thermodynamics associated with ligand binding and subsequent conformational changes.


Asunto(s)
Riboswitch , Ligandos , Conformación de Ácido Nucleico , ARN/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X
19.
Methods Mol Biol ; 2568: 243-249, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36227573

RESUMEN

Time-resolved structure determination of macromolecular conformations and ligand-bound intermediates is extremely challenging, particularly for RNA. With rapid technological advances in both microfluidic liquid injection and X-ray free electron lasers (XFEL), a new frontier has emerged in time-resolved crystallography whereby crystals can be mixed with ligand and then probed with X-rays (mix-and-inject) in real time and at room temperature. This chapter outlines the basic setup and procedures for mix-and-inject experiments for recording time-resolved crystallographic data of riboswitch RNA reaction states using serial femtosecond crystallography (SFX) and an XFEL.


Asunto(s)
Riboswitch , Cristalografía/métodos , Cristalografía por Rayos X , Rayos Láser , Ligandos , ARN
20.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-971131

RESUMEN

OBJECTIVE@#To explore the effect of recombinant human thrombopoietin (rhTPO) on hematopoietic reconstruction in allogeneic hematopoietic stem cell transplantation (allo-HSCT) model.@*METHODS@#The C57BL/6 mice were employed as the donors, and BALB/c mice as recipients. The bone marrow mononuclear cells of the donor mice were extracted and pretreated, which then were injected with 5×106 per mouse through the tail vein of the recipient to establish an allo-HSCT model. The implantation of hematopoietic stem cells in the recipient mice was detected by flow cytometry on the 28th day after transplantation. Next, the successfully modeled recipient mice were randomly divided into experimental group and control group. The rhTPO was injected into mice in the experimental group on the first day after transplantation, while the saline was injected into mice in the control group. Both groups were injected for 14 consecutive days. The peripheral blood and bone marrow hematopoiesis of the two groups were observed on day 1, 3, 7, 14, and 21 after transplantation.@*RESULTS@#The expression rate of H-2Kb in the bone marrow of recipient mice was 43.85% (>20%) on the 28th day after transplantation, which indicated that the recipient mice were successfully chimerized. Meanwhile, counts of PLTs on the day 3, 7, 14, and 21 after transplantation in the experimental group were higher than those in the control group with statistical significances (P<0.05). In addition, hematopoietic function of bone marrow was suppressed in both groups on day 1, 3 and 7 after transplantation, but hematopoietic bone marrow hyperplasia was better in the experimental group than in the control group. On day 14 and 21 after transplantation, the hematopoietic function of bone marrow in the two groups was recovered, and the experimental group showed more obvious than the control group.@*CONCLUSION@#rhTPO can effectively stimulate the production of PLTs and facilitate the recovery of white blood cells and hemoglobin after allo-HSCT, and promote hematopoietic recovery and reconstitution of bone marrow.


Asunto(s)
Humanos , Animales , Ratones , Trombopoyetina , Ratones Endogámicos C57BL , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas , Médula Ósea , Proteínas Recombinantes , Ratones Endogámicos BALB C
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