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1.
Opt Lett ; 49(11): 2994-2997, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824311

RESUMO

We reported on the spectral properties and dual-wavelength laser performances of a novel, to the best of our knowledge, Nd:Gd1.8Y1.2ScAl4O12 (Nd:GYSAG) crystal for the first time. The absorption spectra, emission spectra, and fluorescence lifetime were systematically investigated. Further, a continuous-wavelength (CW) laser output power up to 5.02 W was obtained under an absorbed pump power of 9.45 W with slope and optical-to-optical efficiencies of 59.4% and 53.1%, respectively, at 1061.2 and 1063.2 nm. A stable passively Q-switched (PQS) laser employing Cr:YAG as a saturable absorber (SA) was realized. The maximum average output power of 0.756 W with a slope of near 34.4% was obtained with the pulse width, pulse energy, and peak power of 14.0 ns, 128.1 µJ, and 9.15 kW, respectively. The results indicate that the Nd:GYSAG crystal is an excellent laser medium for generating a high-efficiency dual-wavelength laser and has potential in terahertz (THz) laser generation.

2.
Opt Express ; 32(5): 7865-7872, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439456

RESUMO

We report on the investigation of continuous-wave (CW) and SEmiconductor Saturable Absorber Mirror (SESAM) mode-locked operation of a Yb:GdScO3 laser. Using a single-transverse-mode, fiber-coupled InGaAs laser diode at 976 nm as a pump source, the Yb:GdScO3 laser delivers 343 mW output power at 1062 nm in the CW regime, which corresponds to a slope efficiency of 52%. Continuous tuning is possible across a wavelength range of 84 nm (1027-1111 nm). Using a commercial SESAM to initiate mode-locking and stabilize soliton-type pulse shaping, the Yb:GdScO3 laser produces pulses as short as 42 fs at 1065.9 nm, with an average output power of 40 mW at 66.89 MHz. To the best of our knowledge, this is the first demonstration of passively mode-locking with Yb:GdScO3 crystal.

3.
Inorg Chem ; 63(8): 3807-3814, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38345921

RESUMO

Thorium-doped vacuum ultraviolet (VUV) transparent crystals is a promising candidate for establishing a solid-state nuclear clock. Here, we report the research results on high-concentration doping of 232Th:CaF2 single crystals. The structures, defects, and VUV transmittance performances of highly doped Th:CaF2 crystals are investigated by theoretical and experimental methods. The defect configurations formed by Th and the charge compensation mechanism (Ca vacancy or interstitial F atoms) located at its first nearest neighbor position are mainly considered and studied. The preferred defect configuration is identified according to the doping concentration dependence of structural changes caused by the defects and the formation energies of the defects at different Ca or F chemical potentials. The cultivated Th:CaF2 crystals maintain considerable high VUV transmittance levels while accommodating high doping concentrations, showcasing an exceptional comprehensive performance. The transmittances of 1-mm-thick samples with doping concentrations of 1.91 × 1020 and 2.76 × 1020 cm-3 can reach ∼62% and 53% at 150 nm, respectively. The VUV transmittance exhibits a weak negative doping concentration dependence. The system factors that may cause distortion and additional deterioration of the VUV transmittance are discussed. Balancing and controlling the impacts of various factors will be of great significance for fully exploiting the advantages of Th:CaF2 and other Th-doped crystals for a solid-state nuclear optical clock.

4.
Opt Lett ; 48(21): 5507-5510, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910689

RESUMO

The emission cross section of Nd:LuAG was evaluated using two different methods: the Füchtbauer-Ladenburg equation and the threshold-slope measurements; similar results were obtained with both methods. All measurements and calculations were compared with those of Nd:YAG to reduce uncertainty. Detailed spectroscopic properties of Nd:LuAG were demonstrated. The results showed that the peak emission cross section of Nd:LuAG is approximately 20 × 10-20 cm2, approximately 2/3 the emission cross section of Nd:YAG, instead of the previously reported 9.67 × 10-20 cm2. Additionally, the corresponding saturation flux is 0.9 J/cm2. Therefore, the energy storage capacity of Nd:LuAG is not significantly improved, and it is not sufficient for large-scale amplifiers.

5.
PLoS One ; 18(10): e0293582, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37906580

RESUMO

In many developing economies, high and increasing public debt profile constitutes an essential means of financial risk. An appropriate debt management is germane for survival of business and good international reputation though its effect on private sector credit mobilization had been seldomly investigated. This study seeks to know whether strategic debt management approach exacts a significant effect on the Nigerian private sector and Africa at large resulting to higher credit availability for sustainable enterprise establishment. The study used a time-series observation spanning from 1981-2021. The method of data analysis employed the unit root test for stationarity. Johansen cointegration and vector error correction approach. The result of the unit root test indicates the series were all stationary after first difference and thus were integrated of order1. The Johansen cointegration test support the existence of a cointegrating series between the private credit and its determinants. More empirical evidence from the study shows that proper debt management and increase revenue generation through net taxes on products accounted for 0.93 and 1.32% increase in private sector credit mobilization, while total external debt stock was responsible for a significant negative influence of 0.60% on private sector credit mobilization. The study recommends that the government should always be proactive in their strategic and innovative approach to debt management, revenue generation and sources of funds. This will help not only to avoid crowding out of the private sector but will enhance adequate credit mobilization for effective operations of the private sector.


Assuntos
Administração Financeira , Setor Privado , Comércio , Governo , África
6.
Opt Lett ; 48(16): 4344-4347, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582028

RESUMO

A photonic integrated waveguide amplifier fabricated on erbium-ytterbium (Er-Yb) codoped thin-film lithium niobate (TFLN) has been investigated in this work. A small-signal internal net gain of 27 dB is achieved at a signal wavelength of 1532 nm in the fabricated Er-Yb TFLN waveguide amplifier pumped by a diode laser at ≈980 nm. Experimental characterizations reveal the suitability of waveguide fabrication by the photolithography-assisted chemo-mechanical etching (PLACE) technique and also the gain in an Yb-sensitized-Er material. The demonstrated high-gain chip-scale TFLN amplifier is promising for interfacing with established lithium niobate integrated devices, greatly extending the spectrum of TFLN photonic applications.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-998274

RESUMO

ObjectiveTo evaluate the main structural and content features of four instruments for motor function and motor ability assessment and their psychometric properties for children and adolescents with disabilities, based on International Classification of Functioning, Disability and Health-Children and Youth Version (ICF-CY). MethodsPubMed, Medline and Web of Science databases were searched for literature on motor function and motor ability assessment for children and adolescents with disabilities published from establishment to May, 2023. The main structural and content characteristics of the tools were analyzed using ICF-CY, and the quality of measurement tools was assessed using COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). ResultsNine papers were eventually included, and four assessment tools were identified, including Gross Motor Function Measure-88 (GMFM-88), Peabody Developmental Motor Scales second edition (PDMS-2), Bruininks-Oseretsky Test of Motor Proficiency second edition (BOT-2), and Movement Assessment Battery for Children second edition (MABC-2). The GMFM-88 consisted of 88 items in five dimensions: zone A (lying and rolling), zone B (sitting), zone C (crawling and kneeling), zone D (standing), and zone E (walking and running and jumping); it involved joint movement function (b710), random movement control function (b760), etc., in body function; and the change of basic body posture to maintain a body posture (d410) and maintain a body posture (d415) in activity and participation, with good to excellent levels of internal consistency reliability, test-retest reliability, content validity, and structural validity. The PDMS-2 consisted of six subtests, including reflexes, posture, movement, physical manipulation, grasping and visuomotor integration, with a total of 249 items; it involved memory function (b144) and joint mobility function (b710) in body function; as well as looking (d110) and imitation (d130) in activity and participation; with good psychometric properties in terms of internal consistency reliability, test-retest reliability, content validity, structural validity, and hypothesis testing and cross-cultural feasibility. There are two versions of BOT-2: long form and short form. The long form consisted of eight subtests with 53 items, involving joint mobility function (b710) and joint stability function (b715) in body function; as well as imitation (d130) and learned calculation (d150) in activity and participation; it achieved excellent levels of psychometric properties in terms of internal consistency reliability, content validity, and structural validity, and good level in reliability and test-retest reliability. MABC-2 consisted of two parts: an activity ability test and a checklist with 30 items; it involved joint mobility function (b710), joint stability function (b715), etc., in body function; as well as fine-hand use (d440), hand and arm use (d445) in activity and participation; with good psychometric properties such as reliability, content validity, and structural validity. ConclusionThis systematic review analyzed the main structural and content characteristics of four types of measurement tools for assessing motor function and motor ability in children and adolescents with disabilities based on the ICF-CY, and evaluated the quality of psychometric properties (internal consistency reliability, test-retest reliability, content validity, structural validity, and cross-cultural consistency, etc.) of the four types of measurement tools using the COSMIN criteria. For the structure and content, PDMS-2 appears the broadest content, and measures fine hand movements, dynamic and static balance, along with the BOT-2 and MABC-2. GMFM-88 focuses more on gross motor functions such as postural control. Four instruments show high internal consistency reliability, test-retest reliability, content validity and structural validity, while the BOT-2 and PDMS-2 show better reliability. To ensure the reliability and validity of the measures, rehabilitation workers and educators need to receive standardized training and qualification before using the standardized instruments for motor function and motor ability for children with disabilities. With norm-referenced measures, the results need to be converted to standard scores.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-998210

RESUMO

ObjectiveTo analyze the occurrence of sport injury in Paralympic athletes during the Summer or Winter Paralympic Games, as well as the risk factors for sport injuries and possible interventions. MethodsThe literatures related to sport injuries of Paralympic athletes were searched in PubMed, Web of Science, EBSCO and CNKI from January, 2013 to July, 2022, and a scoping review of the retrieved literature was performed. ResultsFinally, eight English articles from China, Sweden, South Africa, Poland and the United States were included, involving 4 769 atheletes. They included one interview study, five survey studies, one retrospective study and one prospective cohort study, which were mainly from journals in the fields of sport medicine, adaptive sport and sport science, and the publication date was mainly from 2016 to 2022. The types of disability of Paralympic athletes mainly involved physical disability (upper and lower limb amputation, cerebral palsy, spinal cord injury, poliomyelitis, dysplasia and neuromuscular dystrophy, central nervous system injury, myelomeningocele, etc.), intellectual disability and visual disability. The incidence of sport injury was high in Paralympic athletes, and most of the injury occured during competitions. Acute injury, chronic overuse injury and chronic to acute injury were the three most common types of injury. Sports injuries mainly involved head and neck, upper limbs (shoulders, upper arms/forearms, elbows, wrists and fingers), trunk (abdomen, back and waist), and lower limbs (hips/groin, thighs, knees, calves, ankles and toes). Risk factors for sport injuries in Paralympic athletes mainly included previous injury history, illness, fatigue and decreased physical strength, spasticity and muscle weakness; emotional states of inattention or distraction, excessive anxiety or excitement; improper exercise training methods, lack of knowledge related to sport training and injury prevention, and motor skill deficiencies; weather, competition venues, sport facilities, use of equipment and assistive devices, age factors, etc. Injuries of Paralympic athletes could be prevented by providing rehabilitation services for Paralympic athletes, optimizing training design, conducting collective training for coaches and athletes on various types of injuries, conducting research related to sport injuries of disabled athletes, formulating prevention programs and strategies, improving the physical fitness and sport skills of Paralympic athletes, improving emergency treatment techniques for injuries, and strengthening coordination and governance structures between sport medicine and rehabilitation therapists. ConclusionThe incidence of sport injury is high in Paralympic athletes. Chronic overuse injury is the most common injury type, and the injuries most involve head, neck and upper extremities. The risk factors for sport injuries of Paralympic athletes mainly involve physical function, psychological, activities and participation, environment and other factors. The main intervention strategies include providing emergency treatment intervention and monitoring services, sport medicine treatment and rehabilitation, guidance and specialized support, and health education on sport injury prevention.

9.
Opt Express ; 30(12): 21943-21951, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224904

RESUMO

A broader emission band of the novel Nd: CaY0.9Gd0.1AlO4 (Nd: CYGA) mixed crystal was proved by the introduction of Gd3+ ions in Nd: CaYAlO4 (Nd: CYA) crystal, and a diode-pump tunable Nd: CYGA laser operation was achieved successfully. Due to the broad emission spectrum with the full width at half maximum (FWHM) of 23 nm, a tuning range of 32 nm from 1075 nm to 1107 nm was achieved, and the results were considered to be the first time for Nd-doped crystals to be tuned to such a long wavelength at 1107 nm, which promotes the further development of near-infrared tunable lasers. The maximum output power was 1.05 W at the center wavelength of 1081.4 nm, corresponding to the slope efficiency of 26.6%. Furthermore, we also demonstrated a continuous-wave 1105 nm laser with the output power of 53 mW. Our work indicates that Nd: CYGA crystal is a potential Nd-doped gain medium for generating all-solid-state near-infrared lasers.

10.
Theranostics ; 12(13): 5645-5674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966595

RESUMO

Rationale: Sclerostin inhibition demonstrated bone anabolic potential in osteogenesis imperfecta (OI) mice, whereas humanized therapeutic sclerostin antibody romosozumab for postmenopausal osteoporosis imposed clinically severe cardiac ischemic events. Therefore, it is desirable to develop the next generation sclerostin inhibitors to promote bone formation without increasing cardiovascular risk for OI. Methods and Results: Our data showed that sclerostin suppressed inflammatory responses, prevented aortic aneurysm (AA) and atherosclerosis progression in hSOSTki.Col1a2+/G610C.ApoE-/- mice. Either loop2&3 deficiency or inhibition attenuated sclerostin's suppressive effects on expression of inflammatory cytokines and chemokines in vitro, whilst loop3 deficiency maintained the protective effect of sclerostin on cardiovascular system both in vitro and in vivo. Moreover, loop3 was critical for sclerostin's antagonistic effect on bone formation in Col1a2+/G610C mice. Accordingly, a sclerostin loop3-specific aptamer aptscl56 was identified by our lab. It could recognize both recombinant sclerostin and sclerostin in the serum of OI patients via targeting loop3. PEG40k conjugated aptscl56 (Apc001PE) demonstrated to promote bone formation, increase bone mass and improve bone microarchitecture integrity in Col1a2+/G610C mice via targeting loop3, while did not show influence in inflammatory response, AA and atherosclerosis progression in Col1a2+/G610C.ApoE-/- mice with Angiotensin II infusion. Further, Apc001PE had no influence in the protective effect of sclerostin on cardiovascular system in hSOSTki.Col1a2+/G610C.ApoE-/- mice, while it inhibited the antagonistic effect of sclerostin on bone formation in hSOSTki.Col1a2+/G610C mice via targeting loop3. Apc001PE was non-toxic to healthy rodents, even at ultrahigh dose. Apc001PE for OI was granted orphan drug designation by US-FDA in 2019 (DRU-2019-6966). Conclusion: Sclerostin loop3-specific aptamer Apc001PE promoted bone formation without increasing cardiovascular risk in OI mice.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Osteogênese Imperfeita , Animais , Apolipoproteínas E , Modelos Animais de Doenças , Fatores de Risco de Doenças Cardíacas , Camundongos , Oligonucleotídeos , Osteogênese , Osteogênese Imperfeita/tratamento farmacológico , Osteogênese Imperfeita/metabolismo , Fatores de Risco
11.
Nat Commun ; 13(1): 4241, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869074

RESUMO

Sclerostin negatively regulates bone formation by antagonizing Wnt signalling. An antibody targeting sclerostin for the treatment of postmenopausal osteoporosis was approved by the U.S. Food and Drug Administration, with a boxed warning for cardiovascular risk. Here we demonstrate that sclerostin participates in protecting cardiovascular system and inhibiting bone formation via different loops. Loop3 deficiency by genetic truncation could maintain sclerostin's protective effect on the cardiovascular system while attenuating its inhibitory effect on bone formation. We identify an aptamer, named aptscl56, which specifically targets sclerostin loop3 and use a modified aptscl56 version, called Apc001PE, as specific in vivo pharmacologic tool to validate the above effect of loop3. Apc001PE has no effect on aortic aneurysm and atherosclerotic development in ApoE-/- mice and hSOSTki.ApoE-/- mice with angiotensin II infusion. Apc001PE can promote bone formation in hSOSTki mice and ovariectomy-induced osteoporotic rats. In summary, sclerostin loop3 cannot participate in protecting the cardiovascular system, but participates in inhibiting bone formation.


Assuntos
Sistema Cardiovascular , Osteogênese , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apolipoproteínas E , Densidade Óssea , Proteínas Morfogenéticas Ósseas/metabolismo , Sistema Cardiovascular/metabolismo , Feminino , Marcadores Genéticos , Humanos , Camundongos , Ratos
12.
Front Pharmacol ; 13: 847387, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355709

RESUMO

Dickkopf-1 (DKK1) is a well-characterized Wnt inhibitor and component of the Wnt/ß-catenin signaling pathway, whose dysregulation is associated with multiple abnormal pathologies including osteoporosis, Alzheimer's disease, diabetes, and various cancers. The Wnt signaling pathway has fundamental roles in cell fate determination, cell proliferation, and survival; thus, its mis-regulation can lead to disease. Although DKK1 is involved in other signaling pathways, including the ß-catenin-independent Wnt pathway and the DKK1/CKAP4 pathway, the inhibition of DKK1 to propagate Wnt/ß-catenin signals has been validated as an effective way to treat related diseases. In fact, strategies for developing DKK1 inhibitors have produced encouraging clinical results in different pathological models, and many publications provide detailed information about these inhibitors, which include small molecules, antibodies, and nucleic acids, and may function at the protein or mRNA level. However, no systematic review has yet provided an overview of the various aspects of their development and prospects. Therefore, we review the DKK1 inhibitors currently available or under study and provide an outlook on future studies involving DKK1 and drug discovery.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-929680

RESUMO

ObjectiveTo investigate the injury risk of simplified 24-action Taiji Quan wild horse mane splitting practice at different postures with mechanical analysis. MethodsThe mechanical model of the action of Taiji Quan wild horse mane splitting was establishied, and then the coordinates, velocity, acceleration and horizontal angle of thigh and lower leg were determined by image analysis. The force arm of quadriceps femoris was detected by X-ray, and the quadriceps femoris tension, femoral tibial joint force and patellofemoral joint pressure of wild horse mane splitting practice with different postures were compared. ResultsCompared with the high posture, the coordination and velocity decreased, the average angle of knee joint decreased from 128° to 115° at the low posture; and the knee moment, the quadriceps femoris tension, femoral tibial joint force and patellofemoral joint pressure significantly increased (F > 37.187, P < 0.001). ConclusionWhen practicing Taiji Quan wild horse mane splitting, the risk of knee injury at the low posture is higher than that at high posture.

14.
Opt Lett ; 46(16): 3913-3916, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388773

RESUMO

A novel mid-infrared (MIR) laser crystal Co/Er:PbF2 was successfully grown. The use of Er3+ ion co-doping to sensitize a Co2+ ion and enhance the 2.1-4.2 µm broadband MIR emission of the Co2+ ion in a PbF2 crystal was studied for the first time, to the best of our knowledge. The Er3+ ion was demonstrated to be an effective sensitizer of the Co2+ ion, making the Co/Er:PbF2 crystal propitious to be pumped by commercialized laser diodes. Furthermore, with Er3+ ion co-doping, the local symmetry of Co2+ and Er3+ ions was seriously distorted, thereby enhancing the 2.1-4.2 µm MIR emissions. This study provides a path for designing MIR laser materials with optimal performance.

15.
Opt Lett ; 46(15): 3641-3644, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329246

RESUMO

We present, to the best of our knowledge, the first demonstration of thermal, optical, and laser properties of Yb:GdScO3 for potentially efficient ultrashort pulse lasers. The stimulated emission cross section at 1025 nm (E//c) is 0.46×10-20cm2 with the emission band width of 85 nm, even broader than the well-known Yb:CaGdAlO4. It has quite a high thermal conductivity of 5.54W/(m⋅K) at 50°C, comparable with Yb:YAG. In the continuous-wave regime, the maximum output power of 13.45 W at 1063.9 nm was generated with the optical-to-optical efficiency of 63.3%. These results suggest that the Yb:GdScO3 crystal is a promising candidate for ultrashort pulse lasers.

17.
Front Immunol ; 12: 658097, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093545

RESUMO

Clinical studies in a range of cancers have detected elevated levels of the Wnt antagonist Dickkopf-1 (DKK1) in the serum or tumors of patients, and this was frequently associated with a poor prognosis. Our analysis of DKK1 gene profile using data from TCGA also proves the high expression of DKK1 in 14 types of cancers. Numerous preclinical studies have demonstrated the cancer-promoting effects of DKK1 in both in vitro cell models and in vivo animal models. Furthermore, DKK1 showed the ability to modulate immune cell activities as well as the immunosuppressive cancer microenvironment. Expression level of DKK1 is positively correlated with infiltrating levels of myeloid-derived suppressor cells (MDSCs) in 20 types of cancers, while negatively associated with CD8+ T cells in 4 of these 20 cancer types. Emerging experimental evidence indicates that DKK1 has been involved in T cell differentiation and induction of cancer evasion of immune surveillance by accumulating MDSCs. Consequently, DKK1 has become a promising target for cancer immunotherapy, and the mechanisms of DKK1 affecting cancers and immune cells have received great attention. This review introduces the rapidly growing body of literature revealing the cancer-promoting and immune regulatory activities of DKK1. In addition, this review also predicts that by understanding the interaction between different domains of DKK1 through computational modeling and functional studies, the underlying functional mechanism of DKK1 could be further elucidated, thus facilitating the development of anti-DKK1 drugs with more promising efficacy in cancer immunotherapy.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias/etiologia , Neoplasias/metabolismo , Animais , Biomarcadores Tumorais , Gerenciamento Clínico , Suscetibilidade a Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunomodulação , Peptídeos e Proteínas de Sinalização Intercelular/química , Terapia de Alvo Molecular , Neoplasias/terapia , Prognóstico , Transdução de Sinais , Relação Estrutura-Atividade , Resultado do Tratamento , Via de Sinalização Wnt , beta Catenina/metabolismo
18.
Toxicology ; 451: 152694, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33493553

RESUMO

OBJECTIVE: This study was aimed to explore the possible mechanism of environmental metal cadmium (Cd) inducing apoptosis of pig lymph nodes. METHOD: 10 healthy 6-week-old weaned piglets were randomly divided into two groups (n = 5 pigs/group). The control group was fed with a basic diet, and the test group was fed with a basic diet of 20 mg/kg CdCl2. RESULTS: The Cd deposition in mesenteric lymph nodes (MLN), inguinal lymph nodes (ILN) and submaxillary lymph nodes (SLN) after Cd exposure was 2.37 folds, 1.4 folds and 1.8 folds of the control group, respectively. And the rate of MLN and ILN apoptotic cells in the Cd group was 4.11 folds and 9.18 folds of the control group, respectively. The mRNA levels of SOD1, SOD2, CAT, GPX1 and GSH in the Cd group were reduced. Similarly, the two-phase detoxification enzymes had a significant downward trend. Cd exposure decreased the activities of GSH, GSH-Px, SOD, CAT, and increased H2O2 and MDA levels. The mRNA and protein levels of Drp1 and Mff in the Cd group were higher than the corresponding control group, and the mRNA and protein levels of Mfn1 and Mfn2 were lower than those in the control group. In addition, the mRNA and protein levels of pro-apoptotic genes in the Cd group were lower than those in the control group. Cd can significantly reduce the expression of PI3K, AKT and HIF-1α in the three lymph nodes. In summary, Cd induces oxidative stress and regulates the PI3K/AKT/HIF-1α signal transduction pathway to cause mitochondrial dynamics disorder, which leads to the apoptosis of pig lymph nodes, suggesting that Cd-induced mitochondrial pathway apoptosis is related to Cd pig lymph nodes play an important role in the toxicity mechanism.


Assuntos
Cádmio/toxicidade , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Suínos
19.
Ecotoxicol Environ Saf ; 209: 111819, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360786

RESUMO

Cadmium (Cd) is a toxic trace element that can enter the environment with industrial waste and accumulate in the body but the health effects of Cd on ternary pigs are still lacking in research. In order to explore the effect of Cd on the apoptosis of pig spleen and its mechanism, this study chose ternary pig as the research object to detect relevant indicators in pig spleen under Cd exposure. The results of this study showed that Cd exposure can induce apoptosis by promoting the absorption of various toxic trace elements in the spleen and inducing oxidative stress. We also found that the mechanism of Cd-induced apoptosis is closely related to the VDR/CREB1 pathway. On the one hand, Cd exposure can activate VDR, and indirectly regulate the CYP family, affecting the normal function of the spleen. On the other hand, VDR and its downstream genes antagonize the toxicity of Cd by maintaining the stability of the mitochondrial-related endoplasmic reticulum membrane structure. Our research will help researchers to further understand the physiological toxicity of Cd.


Assuntos
Apoptose/fisiologia , Cádmio/toxicidade , Substâncias Perigosas/toxicidade , Baço/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Suínos
20.
Front Cell Dev Biol ; 8: 593269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195264

RESUMO

Connective tissue growth factor (CTGF) is a key signaling and regulatory molecule involved in different biological processes, such as cell proliferation, angiogenesis, and wound healing, as well as multiple pathologies, such as tumor development and tissue fibrosis. Although the underlying mechanisms of CTGF remain incompletely understood, a commonly accepted theory is that the interactions between different protein domains in CTGF and other various regulatory proteins and ligands contribute to its variety of functions. Here, we highlight the structure of each domain of CTGF and its biology functions in physiological conditions. We further summarized main diseases that are deeply influenced by CTGF domains and the potential targets of these diseases. Finally, we address the advantages and disadvantages of current drugs targeting CTGF and provide the perspective for the drug discovery of the next generation of CTGF inhibitors based on aptamers.

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