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1.
Zhongguo Zhen Jiu ; 44(4): 441-448, 2024 Apr 12.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38621732

RESUMO

OBJECTIVES: To observe the effects of electroacupuncture (EA) with "intestinal disease prescription" on the intestinal mucosal barrier and NLRP3 inflammasome in rats with dextran sulfate sodium (DSS)-induced acute ulcerative colitis (UC), and explore the underlying mechanism of EA with "intestinal disease prescription" for the treatment of UC. METHODS: Thirty-two healthy male SPF-grade SD rats were randomly divided into a blank group, a model group, a medication group, and an EA group, with 8 rats in each group. Except for the blank group, the UC model was established by administering 5% DSS solution for 7 days. After modeling, the rats in the medication group were treated with mesalazine suspension (200 mg/kg) by gavage, while the rats in the EA group were treated with acupuncture at bilateral "Tianshu" (ST 25), "Shangjuxu" (ST 37) and "Zhongwan" (CV 12), with the ipsilateral "Tianshu" (ST 25) and "Shangjuxu" (ST 37) connected to the electrodes of the EA instrument, using disperse-dense wave, with a frequency of 10 Hz/50 Hz, and each intervention lasted for 20 minutes. Both interventions were performed once daily for 3 days. The general conditions of rats were observed daily. After intervention, the disease activity index (DAI) score was calculated; colon tissue morphology was observed using HE staining; serum levels of pro-inflammatory cytokines (interleukin [IL]-18, IL-1ß) were measured by ELISA; protein expression of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1 in colon tissues was detected by Western blot; positive expression of zonula occludens-1 (ZO-1) and Occludin in colon tissues was examined by immunofluorescence. RESULTS: Compared with the blank group, the rats in the model group exhibited poor general conditions, slow body weight gain, shortened colon length (P<0.01), increased DAI score and spleen index (P<0.01), elevated serum IL-18 and IL-1ß levels, and increased protein expression of NLRP3, ASC, and Caspase-1 in colon tissues (P<0.01), along with decreased positive expression of ZO-1 and Occludin in colon tissues (P<0.01). Compared with the model group, the rats in the medication group and the EA group exhibited improved general conditions, accelerated body weight gain, increased colon length (P<0.05), reduced DAI scores and spleen indexes (P<0.05), decreased serum IL-18 and IL-1ß levels, and lower protein expression of NLRP3, ASC and Caspase-1 in colon tissues (P<0.05), as well as increased positive expression of ZO-1 and Occludin in colon tissues (P<0.05). There were no significant differences in the above indexes between the medication group and the EA group (P>0.05). Compared with the blank group, the rats in the model group exhibited disrupted colon mucosal morphology, disordered gland arrangement, and atrophy of crypts, along with significant inflammatory cell infiltration. Compared with the model group, the rats in both the medication group and the EA group showed relatively intact colon mucosal morphology, with restored and improved gland and crypt structures, and reduced inflammatory cell infiltration. CONCLUSIONS: EA with "intestinal disease prescription" has a significant therapeutic effect on DSS-induced UC, possibly by regulating the expression of NLRP3 inflammasome and proteins related to the intestinal mucosal barrier, thereby alleviating symptoms of ulcerative colitis.


Assuntos
Colite Ulcerativa , Eletroacupuntura , Ratos , Masculino , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/terapia , Inflamassomos/efeitos adversos , Interleucina-18 , Ratos Sprague-Dawley , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Ocludina , Peso Corporal , Caspases/efeitos adversos
2.
J Environ Manage ; 355: 120488, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38457892

RESUMO

Sulfidation enhances the reactivity of zero-valent iron (ZVI) for Cr(VI) removal from groundwater. Current sulfidation methods mainly focus on chemical and mechanical sulfidation, and there has been little research on biosulfidation using sulfate-reducing bacteria (SRB) and its performance in Cr(VI) removal. Herein, the ability of the SRB-biosulfidated ZVI (SRB-ZVI) system was evaluated and compared with that of the Na2S-sulfidated ZVI system. The SRB-ZVI system forms a thicker and more porous FeSx layer than the Na2S-sulfidated ZVI system, resulting in more sufficient sulfidation of ZVI and a 2.5-times higher Cr(VI) removal rate than that of the Na2S-sulfidated ZVI system. The biosulfidated-ZVI granules and FeSx suspension are the major components of the SRB-ZVI system. The SRB-ZVI system exhibits a long-lasting (11 cycles) Cr(VI) removal performance owing to the regeneration of FeSx. However, the Na2S-sulfidated ZVI system can perform only two Cr(VI) removal cycles. SRB attached to biosulfidated-ZVI can survive in the presence of Cr(VI) because of the protection of the biogenic porous structure, whereas SRB in the suspension is inhibited. After Cr(VI) removal, SRB repopulates in the suspension from biosulfidated-ZVI and produce FeSx, thus providing conditions for subsequent Cr(VI) removal cycles. Overall, the synergistic effect of SRB and ZVI provides a more powerful and environmentally friendly sulfidation method, which has more advantageous for Cr(VI) removal than those of chemical sulfidation. This study provides a visionary in situ remediation strategy for groundwater contamination using ZVI-based technologies.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Ferro/química , Cromo/química , Bactérias , Sulfatos , Poluentes Químicos da Água/química
3.
Int J Gen Med ; 16: 6051-6064, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38148887

RESUMO

Background: Psoriasis is a common chronic, recurrent, and inflammatory skin disease. Identifying novel and potential biomarkers is valuable in the treatment and diagnosis of psoriasis. The goal of this study was to identify novel key biomarkers of psoriasis and analyze the potential underlying mechanisms. Methods: Psoriasis-related datasets were downloaded from the Gene Expression Omnibus database to screen differential genes in the datasets. Functional and pathway enrichment analyses were performed on the differentially expressed genes (DEGs). Candidate biomarkers for psoriasis were identified from the GSE30999 and GSE6710 datasets using four machine learning algorithms, namely, random forest (RF), least absolute shrinkage and selection operator (LASSO) logistic regression, weighted gene co-expression network analysis (WGCNA), and support vector machine recursive feature elimination (SVM-RFE), and were validated using the GSE41662 dataset. Next, we used CIBERSORT and single-cell RNA analysis to explore the relationship between ADAM23 and immune cells. Finally, we validated the expression of the identified biomarkers expressions in human and mouse experiments. Results: A total of 709 overlapping DEGs were identified, including 426 upregulated and 283 downregulated genes. Enhanced by enrichment analysis, the differentially expressed genes (DEGs) were spatially arranged in relation to immune cell involvement, immune-activating processes, and inflammatory signals. Based on the enrichment analysis, the DEGs were mapped to immune cell involvement, immune-activating processes, and inflammatory signals. Four machine learning strategies and single-cell RNA sequencing analysis showed that ADAM23, a disintegrin and metalloprotease, may be a unique, critical biomarker with high diagnostic accuracy for psoriasis. Based on CIBERSORT analysis, ADAM23 was found to be associated with a variety of immune cells, such as macrophages and mast cells, and it was upregulated in the macrophages of psoriatic lesions in patients and mice. Conclusion: ADAM23 may be a potential biomarker in the diagnosis of psoriasis and may contribute to the pathogenesis by regulating immunological activity in psoriatic lesions.

4.
Zhen Ci Yan Jiu ; 48(10): 1033-1040, 2023 Oct 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37879954

RESUMO

OBJECTIVES: To investigate the effect of electroacupuncture(EA) at "Changbing Decoction" on alleviating ulcerative colitis (UC) and regulating the polarization of colonic macrophages in rats, so as to explore its mechanisms underlying improvement of UC. METHODS: Twenty-six male SD rats were randomly divided into 4 groups:normal group(6 rats), model group(8 rats), EA group(6 rats), and western medication group(6 rats). The rat model of UC was established by using 5% dextran sulfate sodium (DSS) solution drinking water for 7 days, followed by drinking 1% DSS solution during treatment period. After 7-day model establishment, EA treatment(10 Hz/50 Hz, 20 min) was applied to "Zhongwan"(CV12), bilateral "Tianshu"(ST25) and "Shangjuxu"(ST37) for 3 d, and rats in the western medication group were given mesalazine suspension(200 mg/kg) by gavage for 3 d. The body weight, spleen weight and colon length of rats were measured. The disease activity index (DAI) score was evaluated. The morphological changes and inflammatory cell infiltration of colon were detected after HE staining and pathological scores were eva-luated. The contents of tumor necrosis factor α(TNF-α), interleukin(IL)-1ß, IL-2 and IL-10 in serum were detected by ELISA. The protein expressions of M1 and M2 macrophage markers nitric oxide synthase (iNOS) and arginase 1(Arg1) were detected by fluorescence double staining and Western blot, respectively. Quantitative real-time PCR was used to detect iNOS and Arg1 mRNA expressions. RESULTS: Compared with the normal group, rats in the model group had increased pathological damage degree and inflammatory cell infiltration in the colon tissue, slowed-down body weight gain, decreased colon length, spleen weight, serum anti-inflammatory factors IL-2 and IL-10 contents, colonic Arg1/CD68 fluorescence positive expression, and Arg1 protein and mRNA expressions(P<0.01, P<0.05), as well as increased DAI scores, colon histopathological scores, contents of serum pro-inflammatory factors TNF-α and IL-1ß, colonic iNOS/CD68 fluorescence positive expression, iNOS protein and mRNA expressions(P<0.01). Compared with the model group, the above indicators were significantly improved in rats of the EA group and the western medication group(P<0.01, P<0.05). CONCLUSIONS: EA of "Changbing Decoction" can improve UC of rats by regulating the polarization of colonic macrophages, inhibiting the generation of M1 macrophages and promoting the generation of M2 macrophages.


Assuntos
Colite Ulcerativa , Eletroacupuntura , Ratos , Masculino , Animais , Colite Ulcerativa/genética , Colite Ulcerativa/terapia , Interleucina-10/genética , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Interleucina-2 , Macrófagos , RNA Mensageiro , Peso Corporal
5.
Zhen Ci Yan Jiu ; 48(8): 818-24, 2023 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-37614141

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zhongwan" (CV12), "Tianshu" (ST25) and "Shangjuxu" (ST37) (an acupoint prescription "Changbingfang" for treatment of intestinal disorders) on autophagy and expression of AMPK/mTOR signaling pathway in rats with ulcerative colitis (UC), so as to explore its mechanism underlying improvement of UC. METHODS: Thirty-two male SD rats were randomly divided into control, model, medication and EA groups, with 8 rats in each group. The UC model was established by free drinking of 5% dextran sulfate sodium salt solution for 7 days. EA stimulation (10 Hz/50 Hz) was delivered to CV12, ST25 and ST37 for 20 min, once a day for 3 consecutive days. Rats of the medication group received gavage of mesalazine suspension (200 mg/kg) once a day, 3 times in total. The rats' general conditions were recorded for calculating the disease activity index (DAI) score (0-4 points). Histomorphological changes of colon were observed via HE staining. The levels of serum interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) and IL-10 were measured by ELISA. The mRNA expressions of LC3B and p62 were tested by fluorescence quantitative PCR. Western blot was used to detect the expression levels of LC3B, p62 and AMPK/mTOR pathway related proteins in colon tissues. RESULTS: Compared with the control group, the DAI score, contents of serum IL-6 and TNF-α, the expression levels of p62 protein and mRNA, ratio of p-mTOR/mTOR were significantly increased (P<0.01); while the content of serum IL-10, the expression levels of LC3B mRNA, ratio of LC3BⅡ/LC3BⅠ and p-AMPK/AMPK were decreased (P<0.01, P<0.05) in the model group. Relevant to the model group, modeling-induced increases of DAI score, serum IL-6, TNF-α and IL-10 contents, expressions of p62 protein and mRNA, LC3B mRNA, ratio of p-mTOR/mTOR, LC3BⅡ/LC3BⅠ and p-AMPK/AMPK were reversed in both medication and EA groups (P<0.01, P<0.05). The effect of EA was apparently superior to that of mesalazine in up-regulating ratio of LC3BⅡ/LC3BⅠ and p-AMPK/AMPK, p62 mRNA expression (P<0.01, P<0.05), and in down-regulating ratio of p-mTOR/mTOR (P<0.05). H.E. staining showed severe damage of the colonic mucosal barrier with infiltration of a large number of inflammatory cells in the model group, which was milder in medication and EA groups. CONCLUSION: EA of acupoint recipe "Changbingfang" can improve the symptoms in UC rats, which may be related to its functions in promoting colonic autophagy, increasing AMPK phosphorylation level, and decreasing mTOR phosphorylation level.


Assuntos
Colite Ulcerativa , Eletroacupuntura , Masculino , Animais , Ratos , Ratos Sprague-Dawley , Colite Ulcerativa/genética , Colite Ulcerativa/terapia , Proteínas Quinases Ativadas por AMP/genética , Interleucina-10 , Mesalamina , Interleucina-6 , Fator de Necrose Tumoral alfa/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , RNA Mensageiro , Autofagia
6.
Cardiovasc Diabetol ; 22(1): 98, 2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120516

RESUMO

BACKGROUND: Since the triglyceride glucose (TyG) index can reflect insulin resistance, it has been proven to be an efficient predictor of glycolipid-metabolism-related diseases. Therefore, this study aimed to investigate the predictive value of the TyG index for visceral obesity (VO) and body fat distribution in patients with type 2 diabetes mellitus (T2DM). METHODS: Abdominal adipose tissue characteristics in patients with T2DM, including visceral adipose area (VAA), subcutaneous adipose area (SAA), VAA-to-SAA ratio (VSR), visceral adipose density (VAD), and subcutaneous adipose density (SAD), were obtained through analyses of computed tomography images at the lumbar 2/3 level. VO was diagnosed according to the VAA (> 142 cm2 for males and > 115 cm2 for females). Logistic regression was performed to identify independent factors of VO, and receiver operating characteristic (ROC) curves were used to compare the diagnostic performance according to the area under the ROC curve (AUC). RESULTS: A total of 976 patients were included in this study. VO patients showed significantly higher TyG values than non-VO patients in males (9.74 vs. 8.88) and females (9.59 vs. 9.01). The TyG index showed significant positive correlations with VAA, SAA, and VSR and negative correlations with VAD and SAD. The TyG index was an independent factor for VO in both males (odds ratio [OR] = 2.997) and females (OR = 2.233). The TyG index ranked second to body mass index (BMI) for predicting VO in male (AUC = 0.770) and female patients (AUC = 0.720). Patients with higher BMI and TyG index values showed a significantly higher risk of VO than the other patients. TyG-BMI, the combination index of TyG and BMI, showed significantly higher predictive power than BMI for VO in male patients (AUC = 0.879 and 0.835, respectively) but showed no significance when compared with BMI in female patients (AUC = 0.865 and 0.835, respectively). CONCLUSIONS: . TyG is a comprehensive indicator of adipose volume, density, and distribution in patients with T2DM and is a valuable predictor for VO in combination with anthropometric indices, such as BMI.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Masculino , Feminino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Glucose , Estudos Transversais , Triglicerídeos , Obesidade Abdominal/diagnóstico , Glicemia/análise , Obesidade/complicações , Obesidade/diagnóstico
7.
Sci Bull (Beijing) ; 67(11): 1154-1169, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36545982

RESUMO

The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood. We report a cell lineage and atlas of developing mouse teeth. We performed a large-scale (92,688 cells) single cell RNA sequencing, tracing the cell trajectories during odontogenesis from embryonic days 10.5 to 16.5. Combined with an assay for transposase-accessible chromatin with high-throughput sequencing, our results suggest that mesenchymal cells show the specific transcriptome profiles to distinguish the tooth types. Subsequently, we identified key gene regulatory networks in teeth and bone formation and uncovered spatiotemporal patterns of odontogenic mesenchymal cells. CD24+ and Plac8+ cells from the mesenchyme at the bell stage were distributed in the upper half and preodontoblast layer of the dental papilla, respectively, which could individually induce nonodontogenic epithelia to form tooth-like structures. Specifically, the Plac8+ tissue we discovered is the smallest piece with the most homogenous cells that could induce tooth regeneration to date. Our work reveals previously unknown heterogeneity and spatiotemporal patterns of tooth germs that may lead to tooth regeneration for regenerative dentistry.


Assuntos
Células-Tronco Mesenquimais , Dente , Camundongos , Animais , Odontogênese/genética , Germe de Dente , Epitélio
8.
Chemosphere ; 308(Pt 2): 136229, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36041530

RESUMO

Molasses have a prominent effect on the bioremediation of Cr(VI) contaminated groundwater. However, its reaction mechanism is not detailed. In this paper, the removal of Cr(VI) with different carbon sources was compared to explore the effect and mechanism of the molasses. The addition of molasses can completely remove 25 mg/L Cr(VI), while the removal efficiency by glucose or emulsified vegetable oil was only 20%. Molasses could rapidly stimulate the reduction of Cr(VI) by indigenous microorganisms and weakened the toxicity on bacteria. The average removal rate of Cr(VI) was 0.42 mg/L·h, 10 times that of glucose system. Compared with glucose, molasses can remediate Cr(VI) at a higher concentration (50 mg/L), and the carbohydrate acted as microbial nutrients. Direct and indirect reduction acted together, the Fe(II) content in the aquifer medium increased from 1.7% to 4.7%. The addition of molasses extract into glucose system could increased the removal rate of Cr(VI) by 2-3 times, and the ions of molasses had no significant effect on the reduction. Excitation emission matrix fluorescence spectra and electrochemical analysis proved that the molasses contained humic acid-like substances, which had the ability of electron shuttle and improved the reduction rate of Cr(VI). In the process of bioreduction, the composition of molasses changed and the electron transport capacity increased from 104.2 to 446.5 µmol/(g C), but these substances could not be used as electron transport media to continuously enhance the reduction effect. This study is of great significance to fully understand the role and application of molasses.


Assuntos
Substâncias Húmicas , Melaço , Biodegradação Ambiental , Carboidratos , Carbono , Cromo/análise , Compostos Ferrosos , Glucose , Substâncias Húmicas/análise , Melaço/análise , Oxirredução , Óleos de Plantas
10.
Int Immunopharmacol ; 102: 108411, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34891001

RESUMO

Autoimmune hepatitis (AIH) is an autoimmune disease characterized by liver parenchymal destruction and chronic fibrosis. Its exact etiology and pathogenesis are not yet fully understood.(Please connect with the following, do not leave a line) Concanavalin A (Con A)-induced mice hepatitis model is a liver injury mediated by T cell and macrophage activation, and its pathogenesis and pathological changes are similar to human AIH. The establishment of this model has greatly promoted the research progress of AIH pathogenesis. However, the exact mechanism of Con A induced liver injury in mice, and its possible defects or deficiencies, has not yet been described in a clear and detailed manner. Therefore, the model has some limitations when applied to the study of the pathogenesis and treatment mechanism of AIH. This article reveals the pathogenesis of Con A induced liver injury in mice from the aspects of immune disorder and coagulation mechanism, expounds the significance of non-coding RNA in this model, summarizes the signal transduction pathways involved in this model, and summarizes the advantages and disadvantages of the model, which provides a theoretical basis and research target for the application of Con A induced liver injury model in AIH in the future.


Assuntos
Concanavalina A/efeitos adversos , Hepatite Autoimune/etiologia , Animais , Transtornos da Coagulação Sanguínea/induzido quimicamente , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Hepatite Autoimune/patologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Camundongos , RNA não Traduzido/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Phys Rev Lett ; 127(18): 180401, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34767426

RESUMO

The time-symmetric formalism endows the weak measurement and its outcome, the weak value, with many unique features. In particular, it allows a direct tomography of quantum states without resorting to complicated reconstruction algorithms and provides an operational meaning to wave functions and density matrices. Here, we propose and experimentally demonstrate the direct tomography of a measurement apparatus by taking the backward direction of weak measurement formalism. Our protocol works rigorously with the arbitrary measurement strength, which offers improved accuracy and precision. The precision can be further improved by taking into account the completeness condition of the measurement operators, which also ensures the feasibility of our protocol for the characterization of the arbitrary quantum measurement. Our work provides new insight on the symmetry between quantum states and measurements, as well as an efficient method to characterize a measurement apparatus.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34732398

RESUMO

INTRODUCTION: Since the ratio of creatinine to cystatin C (Cre/CysC) can reflect muscle volume, it has been proven to be a predictor of sarcopenia in patients with or without diabetes. Here, we investigated the predictive value of Cre/CysC for the skeletal muscle composition and its correlations with glucose disposal ability and diabetic complications in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: The skeletal muscle index (SMI) and mean skeletal muscle attenuation (MMA) values of 193 patients with type 2 diabetes were obtained through analyses of CT images at the lumbar 3 level. RESULTS: Serum Cre/CysC was significantly correlated with both the SMI (r=0.375, p<0.001) and MMA (r=0.378, p<0.001). Multiple stepwise linear regression analysis demonstrated that Cre/CysC was the only biochemical predictor of the SMI (ß=0.48 (95% CI 0.02 to 0.94)) and MMA (ß=0.57 (95% CI 0.14 to 1.01)). Furthermore, the fat mass index (FMI) was significantly associated with the MMA (r=-0.481, p<0.001) but not the SMI (r=0.101, p=0.164). In the diabetic complications analysis, Cre/CysC was significantly lower in patients with cardiovascular disease (95% CI (-1.47 to -0.22), p=0.008) and lower extremity arterial disease (95% CI (-1.44 to -0.29), p=0.004). Moreover, in the 100 g steamed bun test, Cre/CysC was significantly correlated with glucose levels at 60 min (r=-0.162, p=0.045), 120 min (r=-0.287, p<0.001) and 180 min (r=-0.313, p<0.001). CONCLUSIONS: Cre/CysC may be a valuable predictor of skeletal muscle composition in type 2 diabetes. Patients with a higher Cre/CysC may have a better ability to dispose of postprandial glucose and are at a lower risk of macrovascular disease.


Assuntos
Diabetes Mellitus Tipo 2 , Biomarcadores , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Glucose , Humanos , Integrases , Músculo Esquelético/diagnóstico por imagem
13.
Clin Nutr ; 40(5): 3470-3478, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33309414

RESUMO

BACKGROUND: A higher body mass index (BMI) is associated with shorter telomeres. The loss of muscle mass with aging is associated with adverse outcomes. The appendicular skeletal muscle index (ASMI) is currently used to quantify muscle mass. OBJECTIVE: We investigated the association of the ASMI with leukocyte telomere length in adult Americans. METHODS: This cross-sectional study used the National Health and Nutrition Examination Survey (NHANES) 1999-2002 dataset. Body composition was measured by dual-energy X-ray absorptiometry. Low muscle mass was defined using sex-specific thresholds of the appendicular skeletal muscle mass index (ASMI). The telomere-to-single-copy gene ratio (T/S ratio) was converted to base pairs. Generalized linear models were performed to evaluate the association of ASMI with telomere length. RESULTS: In multivariable adjustment regression models, higher ASMI was associated with longer telomeres in US adults (ß = 70.2, P < 0.001, P trend<0.001). In participants with preserved muscle mass, the ASMI was related to longer telomere length (ß = 75.1, P < 0.001), but not significantly in low muscle mass participants (ß = 68.7, P = 0.30). Further subgroup analysis by a combination of age groups and muscle mass status showed positive association with young-preserved muscle mass (ß = 82.6, P < 0.001), old-preserved muscle mass (ß = 44.4, P = 0.12), young-low muscle mass (ß = 135.4, P = 0.20), and old-low muscle mass (ß = 52.7, P = 0.55). Because each additional year of chronological age was associated with telomeres that were 15.3 base pairs shorter, on average, this would equate to 5.4 fewer years of biological aging (82.6 ÷ 15.3) in the young-preserved muscle mass participants. CONCLUSIONS: A higher ASMI is associated with longer telomeres. The prevention of skeletal muscle loss has the potential to delay telomere shortening and account for less biological aging.


Assuntos
Composição Corporal/fisiologia , Leucócitos/citologia , Músculo Esquelético/fisiologia , Telômero/genética , Adulto , Envelhecimento/fisiologia , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais
14.
Phys Rev Lett ; 125(15): 150401, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33095624

RESUMO

In quantum mechanics, geometry has been demonstrated as a useful tool for inferring nonclassical behaviors and exotic properties of quantum systems. One standard approach to illustrate the geometry of quantum systems is to project the quantum state space onto the Euclidean space via measurements of observables on the system. Despite the great success of this method in studying two-level quantum systems (qubits) with the celebrated Bloch sphere representation, it is still difficult to reveal the geometry of multidimensional quantum systems. Here we report the first experiment measuring the geometry of such projections beyond the qubit. Specifically, we observe the joint numerical ranges of a triple of observables in a three-level photonic system, providing a complete classification of these ranges. We further show that the geometry of different classes reveals ground-state degeneracies of a Hamiltonian as a linear combination of the observables, which is related to quantum phases in the thermodynamic limit. Our results offer a versatile geometric approach for exploring the properties of higher-dimensional quantum systems.

15.
Phys Rev Lett ; 125(6): 060404, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32845691

RESUMO

Quantum coherence is a fundamental resource that quantum technologies exploit to achieve performance beyond that of classical devices. A necessary prerequisite to achieve this advantage is the ability of measurement devices to detect coherence from the measurement statistics. Based on a recently developed resource theory of quantum operations, here we quantify experimentally the ability of a typical quantum-optical detector, the weak-field homodyne detector, to detect coherence. We derive an improved algorithm for quantum detector tomography and apply it to reconstruct the positive-operator-valued measures of the detector in different configurations. The reconstructed positive-operator-valued measures are then employed to evaluate how well the detector can detect coherence using two computable measures. As the first experimental investigation of quantum measurements from a resource theoretical perspective, our work sheds new light on the rigorous evaluation of the performance of a quantum measurement apparatus.

16.
Phys Rev Lett ; 124(4): 040402, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058739

RESUMO

The accurate and reliable description of measurement devices is a central problem in both observing uniquely nonclassical behaviors and realizing quantum technologies from powerful computing to precision metrology. To date quantum tomography is the prevalent tool to characterize quantum detectors. However, such a characterization relies on accurately characterized probe states, rendering reliability of the characterization lost in circular argument. Here we report a self-characterization method of quantum measurements based on reconstructing the response range-the entirety of attainable measurement outcomes, eliminating the reliance on known states. We characterize two representative measurements implemented with photonic setups and obtain fidelities above 99.99% with the conventional tomographic reconstructions. This initiates range-based techniques in characterizing quantum systems and foreshadows novel device-independent protocols of quantum information applications.

17.
Phys Rev Lett ; 122(8): 080401, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30932576

RESUMO

Contextuality is considered as an intrinsic signature of nonclassicality and a crucial resource for achieving unique advantages of quantum information processing. However, recently, there have been debates on whether classical fields may also demonstrate contextuality. Here, we experimentally configure a contextuality test for optical fields, adopting various definitions of measurement events, and analyze how the definitions affect the emergence of nonclassical correlations. The heralded single-photon state, which is a typical nonclassical light field, manifests contextuality in our setup; whereas contextuality for classical coherent fields strongly depends on the specific definition of measurement events, which is equivalent to filtering the nonclassical component of the input state. Our results highlight the importance of the definition of measurement events to demonstrate contextuality, and they link the contextual correlations to nonclassicality defined by quasiprobabilities in phase space.

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