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1.
Nature ; 625(7996): 722-727, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38110573

RESUMO

Ecosystems generate a wide range of benefits for humans, including some market goods as well as other benefits that are not directly reflected in market activity1. Climate change will alter the distribution of ecosystems around the world and change the flow of these benefits2,3. However, the specific implications of ecosystem changes for human welfare remain unclear, as they depend on the nature of these changes, the value of the affected benefits and the extent to which communities rely on natural systems for their well-being4. Here we estimate country-level changes in economic production and the value of non-market ecosystem benefits resulting from climate-change-induced shifts in terrestrial vegetation cover, as projected by dynamic global vegetation models (DGVMs) driven by general circulation climate models. Our results show that the annual population-weighted mean global flow of non-market ecosystem benefits valued in the wealth accounts of the World Bank will be reduced by 9.2% in 2100 under the Shared Socioeconomic Pathway SSP2-6.0 with respect to the baseline no climate change scenario and that the global population-weighted average change in gross domestic product (GDP) by 2100 is -1.3% of the baseline GDP. Because lower-income countries are more reliant on natural capital, these GDP effects are regressive. Approximately 90% of these damages are borne by the poorest 50% of countries and regions, whereas the wealthiest 10% experience only 2% of these losses.


Assuntos
Mudança Climática , Países Desenvolvidos , Países em Desenvolvimento , Ecossistema , Produto Interno Bruto , Mudança Climática/economia , Mudança Climática/estatística & dados numéricos , Modelos Climáticos , Países Desenvolvidos/economia , Países em Desenvolvimento/economia , Plantas , Densidade Demográfica , Fatores Socioeconômicos
2.
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.

3.
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.

4.
Clin Radiol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944542

RESUMO

AIM: Radiomics involves the extraction of quantitative data from medical images to facilitate the diagnosis, prognosis, and staging of tumors. This study provides a comprehensive overview of the efficacy of radiomics in prognostic applications for head and neck cancer (HNC) in recent years. It undertakes a systematic review of prognostic models specific to HNC and conducts a meta-analysis to evaluate their predictive performance. MATERIALS AND METHODS: This study adhered rigorously to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for literature searches. The literature databases, including PubMed, Embase, Cochrane, and Scopus were systematically searched individually. The methodological quality of the incorporated studies underwent assessment utilizing the radiomics quality score (RQS) tool. A random-effects meta-analysis employing the Harrell concordance index (C-index) was conducted to evaluate the performance of all radiomics models. RESULTS: Among the 388 studies retrieved, 24 studies encompassing a total of 6,978 cases were incorporated into the systematic review. Furthermore, eight studies, focusing on overall survival as an endpoint, were included in the meta-analysis. The meta-analysis revealed that the estimated random effect of the C-index for all studies utilizing radiomics alone was 0.77 (0.71-0.82), with a substantial degree of heterogeneity indicated by an I2 of 80.17%. CONCLUSIONS: Based on this review, prognostic modeling utilizing radiomics has demonstrated enhanced efficacy for head and neck cancers; however, there remains room for improvement in this approach. In the future, advancements are warranted in the integration of clinical parameters and multimodal features, balancing multicenter data, as well as in feature screening and model construction within this field.

5.
Public Health ; 234: 24-32, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38936116

RESUMO

OBJECTIVES: This study aimed to characterize the most updated utilization of eye care services and obtain a holistic understanding of barriers among patients with diabetes in China. STUDY DESIGN: This was a convergent mixed methods study. METHODS: A convergent triangulation mixed methods approach was used, with a quantitative cross-sectional survey of patients with diabetes and semistructured interviews involving patients and health workers. Following the conceptual framework of the World Health Organization Determinants of Health Behaviours, multivariate logistic regression for quantitative analysis and thematic analysis for qualitative data were used to examine barriers to seeking eye care among patients with diabetes. Triangulation was used to integrate quantitative and qualitative results. RESULTS: Among 1167 surveyed patients who participated in the quantitative component, 29.1% had undergone eye examinations within the last 12 months, and 9.3% had received eye surgery. Awareness that diabetes causes eye diseases (P < 0.001) and knowing laser treatment can treat diabetic retinopathy (DR; P < 0.001) were associated with higher examination rates. In the qualitative component, involving 20 patients and 11 health workers, barriers were identified from individual, social, and cultural environmental factors. Integration of data highlighted the complex interplay of these factors in shaping care-seeking behaviors and the importance of non-economic factors, including patients' information about costs of DR services and cultural environmental factors. CONCLUSIONS: Diabetic eye care utilization remains suboptimal in China, emphasizing the impact of cultural and contextual factors. Comprehensive education strategies, along with training for primary health workers and task-shifting, are likely to enhance eye care service utilization in underserved settings.

6.
J Perianesth Nurs ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38520467

RESUMO

PURPOSE: Heated discussions have divided health care providers and policymakers on the risks versus benefits of general anesthesia in pediatric populations. We conducted this study to provide a comprehensive bibliometric analysis of general anesthesia in this specific population over the past decade. DESIGN: We summarized and quantitatively analyzed the studies related to general anesthesia in children and infants over the past decade. METHODS: Using the Web of Science Core Collection as the data source, we analyzed the literature using CiteSpace software, focusing on authors, countries, institutions, keywords, and references to identify hotspots and predict research trends. FINDINGS: A total of 2,364 publications on pediatric anesthesia were included in the analysis. The number of related publications and citations steadily increased from 2013 to 2022. The United States was the leading country in terms of output, and University of Toronto was the primary contributing institution. Co-citation analysis revealed that over the past decade research has mainly focused on the long-term adverse effects of general anesthesia on neurodevelopment and acute perioperative crisis events. Keyword analysis identified infant sedation and drug selection and compatibility as promising areas for development. In addition, improving the quality of perioperative anesthesia will be a major research focus in the future. CONCLUSIONS: Recent research in pediatric anesthesia has focused on mitigating the adverse effects of general anesthesia in infants and young children and studying the pharmacological compatibility of anesthetics. Our study results would assist researchers and clinicians in understanding the current research status and optimizing clinical practice in this field.

7.
Zhonghua Yi Xue Za Zhi ; 104(21): 2003-2006, 2024 Jun 04.
Artigo em Zh | MEDLINE | ID: mdl-38825945

RESUMO

To investigate the clinical characteristics of metastatic tumors in small intestine. The clinical manifestations, imaging and endoscopic findings, treatment methods and follow-up of patients with small bowel metastatic tumors admitted to the First Affiliated Hospital of Zhengzhou University from January 1, 2018 to December 31, 2022 were retrospectively analyzed. A total of 10 patients were included, including 7 males and 3 females, aged 33-77 (56.4±12.6) years. The main clinical manifestations were intestinal obstruction (8 cases), such as abdominal pain, abdominal distension, nausea, vomiting, and reduced defecation. Some patients had intussusception (abdominal pain, vomiting, black stool and other symptoms, 1 case) or gastrointestinal bleeding (1 case) with early symptoms imperceptible. The primary tumors include gastric cancer (3 cases), malignant melanoma (2 cases), ovarian cancer (2 cases), colon cancer (1 case), rectal cancer (1 case), and lung cancer (1 case). Most of the primary tumors were poorly differentiated (6 cases) or moderately to poorly differentiated (2 cases). The median time from primary tumor surgery to detection of small bowel metastasis [M (Q1, Q3)] was 22 (18, 28) months.The metastatic lesions were single (6 cases) or multiple (4 cases), in both jejunum and ileum. Positron emission tomography-computed tomography (PET-CT, 3 cases) and endoscopy (2 cases) were helpful for detection of small intestinal metastases. The main treatment methods were surgical resection (9 cases), supplemented by radiotherapy, targeted drugs, immunotherapy, etc. Postoperative recurrence and metastasis occurred in some patients (5 cases). Most patients died within 4 to 29 months after diagnosis. Metastatic tumors in small intestine are rare in clinical practice with atypical early symptoms. The patients often present with complications such as intestinal obstruction, which is prone to delayed diagnosis and poor prognosis.


Assuntos
Neoplasias Intestinais , Intestino Delgado , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Idoso , Intestino Delgado/patologia , Adulto , Estudos Retrospectivos , Neoplasias Intestinais/patologia , Obstrução Intestinal/etiologia , Melanoma/patologia , Neoplasias Gástricas/patologia
8.
Zhonghua Yi Xue Za Zhi ; 104(1): 57-62, 2024 Jan 02.
Artigo em Zh | MEDLINE | ID: mdl-38178769

RESUMO

Objective: To investigate the clinical and prognostic characteristics of newly diagnosed multiple myeloma (NDMM) patients with myelofibrosis (MF). Methods: The clinical data of 160 NDMM patients admitted to Henan Provincial People's Hospital from January 2012 to July 2022 were analyzed retrospectively. They were divided into MF group(n=74) and non-MF group(n=86) according to whether combined with MF. Patients in MF group were further splited into MF-1 group (n=47) and MF-2/3 group (n=27). All patients were treated with bortezomib and immunomodulatory-based combination therapy. The efficacy was evaluated after 4 courses, and the clinical features and prognosis between the two groups were compared. The deadline for follow-up was December 30, 2022 and the median follow-up period [M (Q1, Q3)] was 23.5 (14.4, 40.5) months. Kaplan-Meier method was used for survival analysis, and Cox regression model was used to analyze the influencing factors of survival. Results: Among 160 patients with NDMM, 91 were males and 69 were females, with a median age [M (Q1, Q3)] of 59 (54, 69) years. In MF group, the bone marrow immature plasma cell percentage, total plasma cell percentage were 9.6% (3.2%, 28.5%) and 36.4% (18.5%, 51.1%), respectively, which were higher than 6.0% (1.2%, 17.2%) and 24.0% (12.0%, 46.0%) of the non-MF group (both P<0.05). Hb level was 84.0(74.5, 100.5)g/L and PLT was (151.99±90.68) ×109/L in the MF group, which were lower than 96.0 (81.0, 112.0)g/L and (180.38±85.32) ×109/L of non-MF group (both P<0.05). But there were no significant differences in ISS stage, karyotypic and fluorescence in situ hybridization (FISH) high-risk genetic abnormalities between the two groups (all P>0.05). Objective response rate (ORR), overall survival (OS) and progression-free survival (PFS) were not significantly different between the two groups (all P>0.05). The rate of 17p- was 25.9% (7/27) in MF-2/3 group, which was higher than 8.1% (7/86) of non-MF group (P=0.049). The median OS of the MF-2/3 group was 25.0 (95%CI: 23.6-26.4) months, which was shorter than that of the non-MF group (54.0 months, P=0.031). Multivariate Cox regression analysis showed that grade MF-2/3 was not a risk factor for OS in NDMM patients (HR=1.507, 95%CI: 0.624-3.993, P=0.425). Conclusions: The ratio of bone marrow immature plasma cells and total plasma cells in NDMM patients with MF are higher than that in patients without MF, and the Hb and PLT are lower than that in patients without MF. NDMM patients with grade 2/3 MF have shorter survival than those without MF.


Assuntos
Mieloma Múltiplo , Mielofibrose Primária , Masculino , Feminino , Humanos , Prognóstico , Mieloma Múltiplo/diagnóstico , Hibridização in Situ Fluorescente , Estudos Retrospectivos
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(6): 839-846, 2024 Jun 06.
Artigo em Zh | MEDLINE | ID: mdl-38955731

RESUMO

Objective: To investigate the association of urinary cadmium levels with peripheral leukocyte classification counts among middle-aged and older adults aged 40 to 89 years in selected areas of China. Methods: The research was based on the survey of the impact of soil quality of agricultural land on human health in typical areas conducted in 2019-2020. A total of 5 600 middle-aged and older adults aged 40 to 89 years were included by using a multi-stage stratified random sampling method. Baseline characteristics of the subjects were collected and physical examinations were performed. Random midstream urine was collected to measure urinary cadmium and urinary creatinine and fasting venous blood was collected to measure the leukocyte count, neutrophil count, lymphocyte count, monocyte count and eosinophil count. The linear mixed effect model was used to analyse the association of urinary cadmium levels with leukocyte classification counts, and the dose-response relationship between them was analyzed by using the restricted cubic spline (RCS) function. Results: The age of the subjects was (63.17±12.02) years; 2 851 (50.91%) were males; and the M (Q1, Q3) of urinary creatinine-corrected urinary cadmium levels was 2.69 (1.52, 4.69) µg/g·creatinine. After adjusting for confounding factors, the results of linear mixed effects model analysis showed that for each 1-unit increase in urinary creatinine-corrected urinary cadmium level, the percentage change [% (95%CI)] of leukocyte count and lymphocyte count was -1.70% (-2.61%, -0.79%) and -1.57% (-2.86%, -0.26%), respectively. RCS function showed a negative linear relationship between urinary creatinine-corrected urinary cadmium levels and leukocyte counts and lymphocyte counts, respectively (all Pnon-linear>0.05). Conclusion: Urinary cadmium levels are negatively associated with leukocyte count and lymphocyte count among middle-aged and older adults aged 40 to 89 years in selected areas of China.


Assuntos
Cádmio , Humanos , Cádmio/urina , Pessoa de Meia-Idade , China , Idoso , Masculino , Contagem de Leucócitos , Feminino , Adulto , Idoso de 80 Anos ou mais , Creatinina/urina
10.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(6): 529-534, 2024 Jun 12.
Artigo em Zh | MEDLINE | ID: mdl-38858202

RESUMO

Objective: To evaluate the application value of portable pulse oximeter in adult obstructive sleep apnea (OSA). Methods: This study prospectively enrolled adult patients who underwent polysomnography (PSG) due to snoring at the Respiratory and Sleep Medicine Department of Peking University People's Hospital from July 2022 to July 2023. During PSG monitoring, CS-WOxi was continuously used to monitor blood oxygen levels. The consistency between 3% oxygen desaturation index (ODI3) measured by portable pulse oximeter and ODI3 of polysomnography was evaluated using difference test, Pearson's correlation coefficient, and Bland-altman method. Receiver operating characteristic curve was used to determine the optimal threshold for diagnosing OSA. Results: A total of 184 subjects were included, including 121 males (65.8%) and 63 females (34.2%). The mean age was 46.0 (34.3, 59.0) years, body mass index was 26.0 (23.3, 29.6) kg/m², and the apnea-hypopnea index was 18.2 (5.8, 40.8) events/h. There was a significant difference between CS-ODI3 and PSG-ODI3 [17.1(6.2, 42.7) vs. 14.0(2.9, 32.6), P<0.001], and the Pearson correlation coefficient was 0.93 (P<0.001). There was a good correlation between CS-ODI3 and PSG-AHI (r=0.92, P<0.001). Bland-Altman consistency test showed that the average difference between the two was 0.7 events/h, and the 95% consistency limit was (-17.9, 19.3 events/h). When the CS-ODI3≥5 events/h was used to identify OSA, the sensitivity was 94.4%, the specificity was 80.0%, and the accuracy was 91.3%. When PSG-AHI≥5 events/h was used as the diagnostic criteria, the area under the receiver operating characteristic curve was 0.933. Conclusion: Portable pulse oximeter can monitor pulse oxygen saturation accurately and has good sensitivity and specificity for OSA high-risk patients, and is a reliable tool for OSA screening.


Assuntos
Oximetria , Polissonografia , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/sangue , Oximetria/métodos , Oximetria/instrumentação , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Polissonografia/métodos , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Índice de Massa Corporal , Oxigênio/sangue
11.
Zhonghua Gan Zang Bing Za Zhi ; 32(4): 332-339, 2024 Apr 20.
Artigo em Zh | MEDLINE | ID: mdl-38733188

RESUMO

Objective: To evaluate the long-term efficacy of percutaneous microwave ablation (MWA) therapy for hepatocellular carcinoma. Methods: 2054 cases with Barcelona Clinic Liver Cancer (BCLC) stage 0~B at the Fifth Medical Center of the Chinese People's Liberation Army General Hospital from January 2006 to September 2020 were retrospectively collected. All patients were followed up for at least 2 years. The primary endpoint of overall survival and secondary endpoints (tumor-related survival, disease-free survival, and postoperative complications) of patients treated with ultrasound-guided percutaneous MWA were analyzed. Kaplan-Meier method was used for stratified survival rate analysis. Fine-and-Gray competing risk model was used to analyze overall survival. Results: A total of 5 503 HCC nodules [mean tumor diameter (2.6±1.6) cm] underwent 3 908 MWAs between January 2006 and September 2020, with a median follow-up time of 45.6 (24.0 -79.2) months.The technical effectiveness rate of 5 375 tumor nodules was 97.5%. The overall survival rates at 5, 10, and 15-years were 61.6%, 38.8%, and 27.0%, respectively. The tumor-specific survival rates were 67.1%, 47.2%, and 37.7%, respectively. The free tumor survival rates were 25.8%, 15.7%, and 9.9%, respectively. The incidence rate of severe complications was 2.8% (108/3 908). Further analysis showed that the technical effectiveness and survival rate over the passing three time periods from January 2006-2010, 2011-2015, and 2016-September 2020 were significantly increased, with P < 0.001, especially for liver cancer 3.1~5.0 cm (P < 0.001). Conclusion: Microwave ablation therapy is a safe and effective method for BCLC stage 0-B, with significantly enhanced technical efficacy and survival rate over time.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Micro-Ondas , Humanos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/cirurgia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Intervalo Livre de Doença , Ablação por Cateter/métodos , Feminino , Complicações Pós-Operatórias/epidemiologia , Masculino , Pessoa de Meia-Idade
12.
Zhonghua Wai Ke Za Zhi ; 62(7): 697-702, 2024 Jul 01.
Artigo em Zh | MEDLINE | ID: mdl-38808437

RESUMO

Objectives: To evaluate the efficacy and safety of the self-fixing and self-detachable drainage stent in pancreaticojejunostomy and to provide supportive data for the follow clinical trials. Methods: This is an experimental research in animals which completed from February 2022 to September 2022. A self-fixing and self-detachable pancreaticojejunostomy drainage stent was designed for Hong's pancreaticojejunostomy technique based on the theory of "fistula healing" in pancreaticojejunostomy. Ten biocompatibility tests were completed in vitro before this study. Twenty-five Bama minipigs were selected and double-ligated in the neck of the pancreas to dilate the distal main pancreatic duct. Twenty-three of them were successfully modelled and divided into three groups by a stratified random method: pancreaticojejunostomy drainage stent group (referred to as stent group) with 11 pigs, pancreatic duct to jejunal mucosa anastomosis group (referred to as manual suture group) with 8 pigs, sham operation group with 4 pigs. The anastomic time,amylase content in postoperative abdominal drainage fluid and the tolerable pressure value of pancreaticojejunostomy were compared between the stent group and the manual suture group. An abdominal X-ray fluoroscopy examination was adopted to detect the detach time of the stent. A postoperative pathological examination was performed to verify the healing time,the type of treatment and the stricture rate of pancreaticojejunostomy. Quantitative data was analyzed by independent sample t-test. The classified data were analyzed by Fisher's exact test. Results: There were no significant differences in the diameter of the pancreatic duct and pancreatic texture,the time of pancreaticojejunostomy,the amylase content in postoperative peritoneal drainage fluid,and the tolerable pressure value of the pancreaticojejunostomy between the stent group and the manual suture group(all P>0.05). Abdominal X-ray fluoroscopy showed that the stents gradually detached and were removed from the body 21 days after operation,and all stents were detached in the follow 3 months after operation. Pancreaticojejunostomy healed 7 days after operation based on fistula formation in the stent group,and 14 days in the manual suture group. The incidence of anastomotic stricture within 35 days after operation was 2/8 in the stent group and 6/8 in the manual suture group (Fisher's exact test: P=0.132). Conclusion: The stent method is safer and simpler than the manual suture method in pancreaticojejunostomy of Bama minipigs, with shorter anastomotic healing time and lower stricture rate.


Assuntos
Anastomose Cirúrgica , Drenagem , Pancreaticojejunostomia , Stents , Animais , Suínos , Pancreaticojejunostomia/métodos , Drenagem/métodos , Anastomose Cirúrgica/métodos , Pâncreas/cirurgia , Ductos Pancreáticos/cirurgia
13.
Artigo em Zh | MEDLINE | ID: mdl-38964914

RESUMO

Sustained low-intensity muscle fatigue (SULMF) refers to the phenomenon that skeletal muscle continues to contract at less than 10% of maximum voluntary contraction during work activities, resulting in decreased muscle contractile function, which is one of the main causes of occupational neck, shoulder, waist and back discomfort and pain symptoms. Although surface electromyography is a key physiological technique for assessing the efficiency of neuromuscular activity, its effectiveness in objectively detecting SULMF remains controversial. Therefore, this paper describes the neurophysiological mechanism and related hypotheses of SULMF, and reviews the research progress of electromyography detection indicators and detection methods of SULMF, which is of great significance for the early prevention and accurate detection of work-related musculoskeletal disorders.


Assuntos
Eletromiografia , Fadiga Muscular , Humanos , Eletromiografia/métodos , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Músculo Esquelético/fisiopatologia , Contração Muscular/fisiologia
14.
Phys Rev Lett ; 130(11): 112301, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-37001106

RESUMO

We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.

15.
Phys Rev Lett ; 130(8): 082301, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36898098

RESUMO

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, µ_{B}≤110 MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, µ_{B}∼750 MeV at sqrt[s_{NN}]=3 GeV is starkly different from those at vanishing µ_{B}∼24 MeV at sqrt[s_{NN}]=200 GeV and higher collision energies.

16.
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.

17.
FASEB J ; 36(10): e22529, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36036554

RESUMO

Hepatic fibrosis occurs in response to prolonged tissue injury in the liver, which results in abnormal accumulation of extracellular matrix. Hepatic stellate cells (HSCs) have been suggested to play a major role in liver fibrosis. However, the molecular mechanisms remain incompletely understood. Sirtuin 6 (SIRT6), an NAD+ -dependent deacetylase, has been previously implicated in the regulation of the transforming growth factor ß (TGFß)-SMAD3 pathway that plays a significant role in liver fibrosis. In this work, we aimed to identify other important players during hepatic fibrogenesis, which are modulated by SIRT6. Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ or WWTR1), key players in the Hippo pathway, have been implicated in the promotion of hepatic fibrosis. Our data show that HSC-specific Sirt6 knockout mice are more susceptible to high-fat-cholesterol-cholate diet-induced hepatic fibrosis than their wildtype counterparts. Our signaling analyses suggest that in addition to the TGFß-SMAD3 pathway, YAP and TAZ are also highly activated in the SIRT6-deficient HSCs. As it is not clear how SIRT6 might regulate YAP and TAZ, we have decided to elucidate the mechanism underlying the regulation of YAP and TAZ by SIRT6 in HSCs. Overexpression or knockdown of SIRT6 corroborates the role of SIRT6 in the negative regulation of YAP and TAZ. Further biochemical analyses reveal that SIRT6 deacetylates YAP and TAZ and reprograms the composition of the TEA domain transcription factor complex to suppress their downstream target genes, particularly those involved in hepatic fibrosis. In conclusion, our data suggest that SIRT6 plays a critical role in the regulation of the Hippo pathway to protect against hepatic fibrosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Sirtuínas , Animais , Proteínas de Ciclo Celular , Cirrose Hepática , Camundongos , Fosfoproteínas , Fator de Crescimento Transformador beta
18.
FASEB J ; 36(1): e22125, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34958687

RESUMO

Aging is associated with gradual changes in liver structure and physiological/pathological functions in hepatic cells including hepatocytes, cholangiocytes, Kupffer cells, hepatic stellate cells (HSCs), and liver sinusoidal endothelial cells (LSECs). LSECs are specialized hepatic endothelial cells that regulate liver homeostasis. These cells actively impact the hepatic microenvironment as they have fenestrations and a thin morphology to allow substance exchange between circulating blood and the liver tissue. As aging occurs, LSECs have a reduction in both the number and size of fenestrations, which is referred to as pseudocapillarization. This along with the aging of the liver leads to increased oxidative stress, decreased availability of nitric oxide, decreased hepatic blood flow, and increased inflammatory cytokines in LSECs. Vascular aging can also lead to hepatic hypoxia, HSC activation, and liver fibrosis. In this review, we described the basic structure of LSECs, and the effect of LSECs on hepatic inflammation and fibrosis during aging process. We briefly summarized the changes of hepatic microcirculation during liver inflammation, the effect of aging on the clearance function of LSECs, the interactions between LSECs and immunity, hepatocytes or other hepatic nonparenchymal cells, and the therapeutic intervention of liver diseases by targeting LSECs and vascular system. Since LSECs play an important role in the development of liver fibrosis and the changes of LSEC phenotype occur in the early stage of liver fibrosis, the study of LSECs in the fibrotic liver is valuable for the detection of early liver fibrosis and the early intervention of fibrotic response.


Assuntos
Envelhecimento , Endotélio Vascular/metabolismo , Hipóxia , Cirrose Hepática , Fígado , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Doença Crônica , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia
19.
J Endocrinol Invest ; 46(8): 1633-1650, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36725810

RESUMO

PURPOSE: Anaplastic thyroid cancer (ATC) is a rare and lethal malignant cancer. In recent years, the application of molecular-driven targeted therapy and immunotherapy has markedly improved the prognosis of ATC. This study aimed to identify characteristic genes for ATC diagnosis and revealed the role of ATC characteristic genes in drug sensitivity and immune cell infiltration. METHODS: We downloaded ATC RNA-sequencing data from the GEO database. Following the combination and normalization of the dataset, we first divided the combined datasets into the training cohort and the validation cohort. We identified differentially expressed genes (DEGs) in ATC by differential expression analysis in the training cohort. We used two machine learning algorithms, least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) to identify ATC characteristic genes. The CIBERSORT algorithm was performed to calculate the abundance of various immune cells in ATC. Finally, we validated the expression of ATC characteristic genes by quantitative RT-PCR (RT-qPCR) in ATC cell lines and immunohistochemistry (IHC). RESULTS: A total of 425 DEGs were identified in the training cohort, including 240 upregulated genes and 185 downregulated genes. Four ATC characteristic genes (ADM, PXDN, MMP1, and TFF3) were identified, and their diagnostic value was validated in the validation cohort (AUC in ROC analysis > 0.75). We established a practical gene expression-based nomogram to accurately predict the probability of ATC. We also found that ATC characteristic biomarkers are associated with the tumor immune microenvironment and drug sensitivity. CONCLUSION: ADM, PXDN, MMP1, and TFF3 might serve as potential ATC diagnostic biomarkers and may be helpful for ATC molecular targeted therapy and immunotherapy.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Anaplásico da Tireoide/diagnóstico , Carcinoma Anaplásico da Tireoide/genética , Metaloproteinase 1 da Matriz , Biomarcadores , Algoritmos , Aprendizado de Máquina , Microambiente Tumoral
20.
Nucleic Acids Res ; 49(10): 5726-5742, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34023907

RESUMO

Appropriate regulation of the Integrated stress response (ISR) and mTORC1 signaling are central for cell adaptation to starvation for amino acids. Halofuginone (HF) is a potent inhibitor of aminoacylation of tRNAPro with broad biomedical applications. Here, we show that in addition to translational control directed by activation of the ISR by general control nonderepressible 2 (GCN2), HF increased free amino acids and directed translation of genes involved in protein biogenesis via sustained mTORC1 signaling. Deletion of GCN2 reduced cell survival to HF whereas pharmacological inhibition of mTORC1 afforded protection. HF treatment of mice synchronously activated the GCN2-mediated ISR and mTORC1 in liver whereas Gcn2-null mice allowed greater mTORC1 activation to HF, resulting in liver steatosis and cell death. We conclude that HF causes an amino acid imbalance that uniquely activates both GCN2 and mTORC1. Loss of GCN2 during HF creates a disconnect between metabolic state and need, triggering proteostasis collapse.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/genética , Estresse Fisiológico/genética , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Códon/genética , Ontologia Genética , Fígado/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Polirribossomos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Inibidores da Síntese de Proteínas/administração & dosagem , Inibidores da Síntese de Proteínas/farmacologia , Quinazolinonas/administração & dosagem , Quinazolinonas/farmacologia , RNA de Transferência/genética , RNA de Transferência/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos
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