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1.
Huan Jing Ke Xue ; 45(7): 4122-4136, 2024 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-39022960

ABSTRACT

Assessment and monitoring of the quality of the ecological environment in the area is a very important fundamental task in the development of ecological civilization in the Xiaojiang River Basin in Yunnan Province, which serves as a demonstration area for ecological restoration in the upper reaches of the Yangtze River. The Landsat remote sensing images from 1990, 1995, 2000, 2005, 2010, 2014, 2018, and 2022 were chosen, and the four indexes of greenness (NDMVI), humidity (WET), dryness (NDBSI), and heat (LST) were extracted. The remote sensing ecological index (RSEI) was created using the principal component analysis method, then the spatial and temporal patterns and trends of ecological quality in the Xiaojiang River Basin between 1990 and 2022 were examined using the GEE platform, ArcGIS 10.7 platform, and Python platform, combining the analysis methods of geographic information mapping, coefficient of variation, Mann-Kendall trend test, Sen's slope estimation, and Hurst's index. The findings demonstrated that: ① the ecological quality of the study area had more obvious geographic differentiation spatially, and by 2022, the areas with excellent and good ecological quality grades were primarily distributed in the areas with better alpine vegetation cover, and those with poor ecological quality were primarily distributed in the areas of the mudslide ravines with relatively low terrain. On a time scale, the study area's RSEI index increased from 0.41 in 1990 to 0.55 in 2022, with a fluctuating overall trend of ecological quality improvement and an average increase of 0.048(10 a) -1; this progress was directly related to a number of ecological construction initiatives that have been energetically carried out, such as converting farms to forests, preventing mudslides, saving soil and water, managing heavy metal contamination, etc. ② The RSEI was more appropriate for the evaluation of ecological quality in alpine ravine areas because, in comparison to the NDVI index, the NDVMI adopted in this study was more sensitive to vegetation information in topographic undulation areas, especially in shaded areas, and could more accurately and quantitatively describe the vegetation information. ③ The RSEI in the Xiaojiang River Basin had a mean coefficient of variation of 0.202. Overall, its volatility was low, and its high volatility was mostly concentrated in the mudslide gully area along both sides of the Xiaojiang River fracture zone, where the surface was made up of bare rocks and sediment that was easily impacted by the changing of the seasons, the climate, and human activity. ④ The quality of the ecological environment in the region was significantly improving, with the rising area reaching 85.72% of the total area and the declining area accounting for approximately 10.15% of the total area. The future trend of change will be dominated by ongoing improvement and future degradation, accounting for 44.75% and 39.97%, respectively. It is important to pay close attention to areas that could potentially degrade. The findings of this study can serve as a theoretical foundation for additional ecological environmental conservation, management, and sustainable development in the Xiaojiang River Basin.

2.
J Orthop Surg Res ; 19(1): 82, 2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38245753

ABSTRACT

BACKGROUND: Lateral wall fractures represent crucial risk factors for postoperative internal fixation failure in intertrochanteric femoral fractures. However, no consensus exists on the type of lateral wall fracture requiring interventional management. This study aimed to investigate the effect of residual lateral wall volume on the postoperative stability of intertrochanteric femur fractures with associated lateral wall fractures, providing valuable reference for the clinical management of the lateral wall. METHODS: Eleven bone defect models of intertrochanteric femur fractures with varying residual lateral wall volumes were constructed using finite element analysis. These models were fixed with proximal femoral nail antirotation (PFNA). Simulations of von Mises stress and displacement distribution of the PFNA and femur during normal walking were conducted. Statistical analysis was performed to assess the correlation between volume and the maximum von Mises stresses and displacements of the PFNA and femur. RESULTS: In all 11 models, the maximum von Mises stress and displacement of the helical blade, intramedullary nail, and femur occurred at the same locations. As residual lateral wall volume increased, the maximum von Mises stress and displacement of the helical blade, intramedullary nail, and maximum femoral displacement gradually decreased. However, the overall trend of the maximum femoral von Mises stress gradually decreased. At 70% retention of the residual lateral wall volume, there was a more pronounced change in the value of the maximum stress change of the helical blade and the intramedullary nail. Statistical analysis, including the Shapiro-Wilk test and Pearson correlation analysis, demonstrated a significant negative correlation between volume and the maximum von Mises stress and displacement of the helical blade, intramedullary nail, and femur. Linear regression analysis further confirmed this significant negative correlation. CONCLUSION: Finite element analysis of the residual lateral wall revealed a significant correlation between volume and the postoperative stability of intertrochanteric femur fractures. A volume of 70% may serve as the threshold for stabilizing the residual lateral wall. Volume emerges as a novel index for evaluating the strength of the residual lateral walls.


Subject(s)
Fracture Fixation, Intramedullary , Hip Fractures , Humans , Finite Element Analysis , Bone Nails , Hip Fractures/diagnostic imaging , Hip Fractures/surgery , Femur/diagnostic imaging , Femur/surgery , Fracture Fixation, Internal
3.
J Cancer Res Ther ; 19(4): 876-880, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37675711

ABSTRACT

Background: Soft-tissue sarcomas during infancy are rare and understudied. With no data on this specific condition, we performed a retrospective study of infant-onset sarcomas based on a multi-institutional cohort in Beijing, China, collected over the past decade. We reviewed infantile soft-tissue sarcomas' clinical characteristics, treatments, and outcomes. Materials and Methods: The patients with soft-tissue sarcoma diagnosed from 0 to 12 months in four primary children's hospitals in Beijing from January 2010 to December 2019 were evaluated. Results: Fifty-one patients were enrolled, including 31 males and 20 females. The median age at the diagnosis was five months (range, 0-12), and seven (13.7%) patients were diagnosed in the first month of their life. Histologically, twenty-five patients were diagnosed with rhabdomyosarcoma (RMS), six were diagnosed with extraosseous Ewing sarcoma (EES), and twenty were diagnosed with nonrhabdomyosarcoma soft-tissue sarcoma (NRSTS). The treatment principles and details of RMS focused on reference to the Intergroup Rhabdomyosarcoma Study Group (IRSG) protocols. For EES and NRSTS, chemotherapy was prescribed according to children's oncology group protocols. The five-year EFS/OS rates of RMS were 26.4% ± 19.5%/56.2 ± 17.8%, the five-year EFS/OS rate of EES was 50% ± 20.4%, and the five-year EFS/OS of NRSTS was 85.2% ± 9.8%/100%. Conclusions: Infant-onset soft-tissue sarcoma is heterogeneous. The primary location of the abdominal or pelvic cavity of RMS and EWS was at a later stage and had a poorer prognosis. Multimodal therapy resulted in successful disease control for the majority of patients. Standardization of treatment protocols will facilitate care for such challenging conditions.


Subject(s)
Rhabdomyosarcoma , Sarcoma, Ewing , Sarcoma , Soft Tissue Neoplasms , Child , Female , Humans , Infant , Infant, Newborn , Male , China/epidemiology , Multicenter Studies as Topic , Retrospective Studies , Sarcoma/diagnosis , Sarcoma/epidemiology , Sarcoma/therapy , Sarcoma, Ewing/diagnosis , Sarcoma, Ewing/epidemiology , Sarcoma, Ewing/therapy , Soft Tissue Neoplasms/diagnosis , Soft Tissue Neoplasms/epidemiology , Soft Tissue Neoplasms/therapy , Child, Preschool
4.
Eur J Pediatr ; 180(7): 2055-2063, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33580827

ABSTRACT

Neuroblastoma (NB) is the most common extracranial solid tumor in childhood, with 37% of patients diagnosed during infancy. This study is aimed at evaluating the survival outcome in infants diagnosed with neuroblastoma. This was a retrospective cohort study including patients under the age of 12 months with neuroblastoma from four tertiary referral centers in Beijing, China (Beijing Children's Hospital, Beijing Tongren Hospital, Peking University First Hospital, and Capital Institute of Pediatrics). Two hundred and forty-seven infants with neuroblastoma were included (male = 132 and female = 115). 91.1% (n = 225) patients were classified as having low-risk or intermediate-risk disease and 8.9% (n = 22) as having high-risk disease. The most common metastatic site is distant lymph node (n=89, 36.0%), followed by liver (n=57, 23.1%), bone (n=42, 17.0%), bone marrow (n=37, 15.0%), soft tissue (n=25, 10%), and central nervous system (n=4, 1.6%). MYCN amplification was present in 9.9% of tumor samples, chromosome 1p or 11q aberration in 14%. Treatment involved surgery alone in 9.7% of patients (n=24, all with low-risk disease), surgery followed by adjuvant chemotherapy in 50.2% (n=124), neoadjuvant chemotherapy followed by surgery in 40.1% (n=97), and chemotherapy alone in 0.8% (n=2). 4.9% (n=12) patients died, and the major cause of death is disease progression. Three-year event-free and overall survival were 91.6%±2.1% and 97.4%±1.1%, respectively, in patients with low- or intermediate-risk disease, and 58.7%±11.5% and 63.6%±11.2%, respectively, in those with high-risk disease.Conclusions: Infants with neuroblastoma achieve a reasonable clinical outcome when treated with surgery with or without chemotherapy using a risk-stratified approach in China. Such information will facilitate counseling, therapeutic decision-making, and development of adapted standard-of-care guidelines for future patients in the country. What is Known: • NB is a disease of infancy; 37% of patients are diagnosed as infants. • Most children younger than 12 months of age have a good prognosis even in the presence of metastatic disease. What is New: • Infants with neuroblastoma achieve reasonable clinical outcome when treated with surgery with or without chemotherapy using a risk-stratified approach in China. • CNS metastasis in infants with neuroblastoma is very rare at diagnosis and had a worse prognosis than those without metastasis.


Subject(s)
Neuroblastoma , Child , China/epidemiology , Disease Progression , Female , Humans , Infant , Male , Neoplasm Staging , Neuroblastoma/diagnosis , Neuroblastoma/pathology , Neuroblastoma/therapy , Prognosis , Retrospective Studies
5.
Pediatr Investig ; 4(3): 178-185, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33150311

ABSTRACT

IMPORTANCE: Cancer is the main cause of death by disease in children. Children experience the highest incidence of cancer in the first year of life. However, there is no comprehensive registration system for children with tumors in China. OBJECTIVE: To summarize the diagnosis and treatment of infant cancer and analyze the status of standardized diagnosis and management among several treatment centers in Beijing, China, thereby providing evidence to guide further clinical research. METHODS: From January 1, 2010 to December 31, 2019, patients with newly diagnosed infantile malignant solid tumors were admitted to six large tertiary pediatric solid tumor diagnosis and treatment centers in Beijing. The epidemiology, clinical features, and therapeutic effects of tumors in these patients were analyzed retrospectively. All patients were followed up until March 31, 2020. RESULTS: In total, 938 patients were enrolled in this study. There were 530 boys (56.5%) and 408 girls (43.5%); the median age was 6.0 months (range, 0-12.0 months). The three most common tumors were retinoblastoma in 366 patients (39.0%), neuroblastoma in 266 patients (28.4%), hepatoblastoma in 133 patients (14.2%), and central nervous system tumors in 52 patients (5.5%). The estimated 5-year overall survival rate was 81.3% ± 1.8%, and the 5-year event-free survival rate was 71.8% ± 2.9%. The 5-year overall survival rates of non-rhabdomyosarcoma soft tissue sarcoma, neuroblastoma, and retinoblastoma were 100%, 88% ± 2.2%, and 86.9% ±2.1%, respectively. The 5-year event-free survival rates were 81.1% ± 2.7% for neuroblastoma, 81.6% ± 9.8% for non-rhabdomyosarcoma soft tissue sarcoma, and 72.7% ± 14.1% for extracranial malignant germ cell tumors. INTERPRETATION: The three most common infantile malignant solid tumors were retinoblastoma, neuroblastoma, and hepatoblastoma. Multidisciplinary combined diagnosis and treatment is needed for infantile tumors.

6.
Proc Natl Acad Sci U S A ; 103(26): 10005-10, 2006 Jun 27.
Article in English | MEDLINE | ID: mdl-16785445

ABSTRACT

The mammalian protein kinase PKR is a critical component of the innate immune response against virus infection. Its cellular actions are mediated by modulating cell signaling and translational regulation. To be enzymatically active, latent PKR needs to be activated by binding to one of its activators, dsRNA or PACT protein. Although the structures of the N-terminal dsRNA-binding domain and the C-terminal kinase domain of PKR have been separately determined, the mode of activation of the enzyme remains unknown. To address this problem, we used biochemical, genetic, and NMR analyses to identify the PACT-binding motif (PBM) located in the kinase domain and demonstrated an intramolecular interaction between PBM and dsRNA-binding domain. This interaction is responsible for keeping PKR in an inactive conformation, because its disruption by point mutations of appropriate residues produced constitutively active PKR. Furthermore, a short decoy peptide, representing PBM, was able to activate PKR by interfering with the intramolecular interaction. These observations suggest a model for PKR activation upon binding of dsRNA or PACT.


Subject(s)
RNA, Double-Stranded/metabolism , RNA-Binding Proteins/metabolism , eIF-2 Kinase/metabolism , Amino Acid Motifs/genetics , Cells, Cultured , Enzyme Activation , Humans , Mutation , Nuclear Magnetic Resonance, Biomolecular , Nuclear Proteins/metabolism , Peptides/chemistry , Peptides/metabolism , Protein Interaction Mapping , Protein Structure, Tertiary/genetics , eIF-2 Kinase/chemistry , eIF-2 Kinase/genetics
7.
Acta Crystallogr D Biol Crystallogr ; 59(Pt 10): 1831-3, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14501129

ABSTRACT

Atrial natriuretic peptide (ANP) plays a major role in blood pressure and volume regulation owing to its natriuretic and vasodilatory activities. The ANP receptor is a single-span transmembrane receptor coupled to its intrinsic guanylyl cyclase activity. The extracellular hormone-binding domain of rat ANP receptor (ANPR) was overexpressed by permanent transfection in CHO cells and purified. ANPR complexed with ANP was crystallized at 301 K by the hanging-drop vapor-diffusion method. The crystals were frozen in 3.4 M ammonium sulfate used as a cryoprotectant. The crystals diffracted to 3.1 A resolution using synchrotron radiation and belonged to the hexagonal space group P6(1), with unit-cell parameters a = b = 100.3, c = 258.6 A.


Subject(s)
Ammonium Sulfate/chemistry , Atrial Natriuretic Factor/chemistry , Receptors, Atrial Natriuretic Factor/chemistry , Animals , CHO Cells , Cricetinae , Crystallization/methods , Crystallography, X-Ray , Extracellular Space/chemistry , Models, Molecular , Protein Structure, Tertiary , Rats , Receptors, Atrial Natriuretic Factor/biosynthesis , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Static Electricity
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