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1.
Article in English | MEDLINE | ID: mdl-37933868

ABSTRACT

The defective structure and high oxygen vacancy concentration of SrFeO3-δ perovskite enable fast ion-electron transport, but its low conductivity still hinders the high electrochemical performance. Herein, to enhance the conductivity of SrFeO3-δ-based electrodes, polypyrrole-modified SrFeO3-δ perovskite on carbon cloth (PPy@SFO@CC) has been successfully fabricated by electrodeposition of polypyrrole (PPy) on the surface of SFO@CC. The optimal PPy700@SFO@CC electrode exhibits a specific capacitance of 421 F g-1 at 1 A g-1. It was found that the outside PPy layer not only accelerates the electron transport and ion diffusion but also creates more oxygen vacancies in SrFeO3-δ, enhancing the charge storage performance significantly. Moreover, the NiCo2O4@CC//PPy700@SFO@CC device maintains a specific capacitance of 63.6% after 3000 cycles, which is ascribed to the weak adhesion forces between the active materials and carbon cloth. Finally, the all-solid-state flexible supercapacitor NiCo2O4@CC//PPy700@SFO@CC is constructed with PVA-KOH as the solid electrolyte, delivering an energy density of 16.9 W h kg-1 at a power density of 984 W kg-1. The flexible supercapacitor retains 69% of its specific capacitance after 1000 bending and folding times, demonstrating a certain degree of foldability. The present study opens new avenues for perovskite oxide-based flexible all-solid-state supercapacitors.

2.
Hepatobiliary Pancreat Dis Int ; 22(5): 498-503, 2023 Oct.
Article in English | MEDLINE | ID: mdl-35534341

ABSTRACT

BACKGROUND: Remote ischemic perconditioning (RIPerC) has been demonstrated to protect grafts from hepatic ischemia-reperfusion injury (IRI). This study investigated the role of exosomes in RIPerC of liver grafts in rats. METHODS: Twenty-five rats (including 10 donors) were randomly divided into five groups (n = 5 each group): five rats were used as sham-operated controls (Sham), ten rats were for orthotopic liver transplantation (OLT, 5 donors and 5 recipients) and ten rats were for OLT + RIPerC (5 donors and 5 recipients). Liver architecture and function were evaluated. RESULTS: Compared to the OLT group, the OLT + RIPerC group exhibited significantly improved liver graft histopathology and liver function (P < 0.05). Furthermore, the number of exosomes and the level of P-Akt were increased in the OLT + RIPerC group. CONCLUSIONS: RIPerC effectively improves graft architecture and function, and this protective effect may be related to the increased number of exosomes. The upregulation of P-Akt may be involved in underlying mechanisms.


Subject(s)
Exosomes , Liver Transplantation , Reperfusion Injury , Rats , Animals , Liver Transplantation/adverse effects , Proto-Oncogene Proteins c-akt , Exosomes/pathology , Reperfusion Injury/etiology , Reperfusion Injury/prevention & control , Reperfusion Injury/pathology , Ischemia , Liver/surgery , Liver/pathology , Reperfusion
4.
Appl Opt ; 61(26): 7547-7551, 2022 Sep 10.
Article in English | MEDLINE | ID: mdl-36256351

ABSTRACT

Directly modulated vector beam lasers are increasingly desirable for wide applications ranging from optical manipulation to optical communications. We report the first, to our knowledge, high-speed directly modulated vector beam laser with azimuthally polarized emission. It is a microcylinder cavity interacted with a proper second-order grating on top, which enables single mode lasing and efficient surface emission. Through theoretical and numerical analysis, the laser is designed in detail. With an optimized top grating, the emission of the laser is an azimuthally polarized vector beam. With high-differential-gain material and a small active region, the laser can be directly modulated with a high 3 dB bandwidth reach of 40 GHz in simulation. The proposed high-speed directly modulated semiconductor laser with an azimuthally polarized vector beam is promising for applications in fiber space communications or quantum information.

5.
Front Med (Lausanne) ; 9: 870926, 2022.
Article in English | MEDLINE | ID: mdl-35572984

ABSTRACT

Background: Facial skin is exposed to the environment, which marks it with obvious signs of aging. Based on multi-dimensional non-invasive evaluation data, female facial skin can be characterized in detail. However, there are few studies on the general aging rules of facial skin. Most skin aging studies divide the ages into 5-10-year intervals, so they have lacked dynamic matching with facial skin aging. Aim: To explore facial skin aging rules, discuss the main parameters of facial skin aging, propose an unequal-distance aging division method based on the main skin parameters, and study the skin characteristics of Chinese women of different aging stages. Methods: We comprehensively described the skin status as 24 non-invasive skin parameters belonging to five dimensions: skin wrinkles, texture, stain, color and barrier function. We performed polynomial fitting on the 21 skin parameters that were significantly correlated with age and derived the rules of aging in the different dimensions. Based on the wrinkle dimension, the facial skin aging process was divided into four stages, and the skin characteristics of the different stages were compared. Results: Skin wrinkles increased, texture deteriorated, acne decreased, pigment spots increased, skin tone darkened, and sebum secretion decreased with age, according to the polynomial fitting. The aging stage was divided into an incubation period (18-30 years old), an aging occurrence period (31-42 years old), a rapid aging period (43-47 years old), and a stable aging period (48-60 years old), according to the wrinkles. Different aging stages had different skin characteristics. Conclusion: The incubation period is the critical period for the appearance of skin stains; the skin texture gradually deteriorates during the aging occurrence period; the rapid aging period is a critical period for the aging of skin parameters; skin status during the stable aging period is the worst.

6.
Nano Lett ; 21(16): 7005-7011, 2021 Aug 25.
Article in English | MEDLINE | ID: mdl-34350759

ABSTRACT

The Mott state in 1T-TaS2 is predicted to host quantum spin liquids (QSLs). However, its insulating mechanism is controversial due to complications from interlayer coupling. Here, we study the charge transfer state in monolayer 1T-NbSe2, an electronic analogue to TaS2 exempt from interlayer coupling, using spectroscopic imaging scanning tunneling microscopy and first-principles calculations. Monolayer NbSe2 surprisingly displays two types of star of David (SD) motifs with different charge transfer gap sizes, which are interconvertible via temperature variation. In addition, bilayer 1T-NbSe2 shows a Mott collapse by interlayer coupling. Our calculation unveils that the two types of SDs possess distinct structural distortions, altering the effective Coulomb energies of the central Nb orbital. Our calculation suggests that the charge transfer gap, the same parameter for determining the QSL regime, is tunable with strain. This finding offers a general strategy for manipulating the charge transfer state in related systems, which may be tuned into the potential QSL regime.

7.
ACS Nano ; 15(5): 8184-8191, 2021 May 25.
Article in English | MEDLINE | ID: mdl-33723991

ABSTRACT

Exploring two-dimensional (2D) van der Waals (vdW) systems is at the forefront of materials of physics. Here, through molecular beam epitaxy on graphene-covered SiC(0001), we report successful growth of AlSb in the double-layer honeycomb (DLHC) structure, a 2D vdW material which has no direct analogue to its 3D bulk and is predicted to be kinetically stable when freestanding. The structural morphology and electronic structure of the experimental 2D AlSb are characterized with spectroscopic imaging scanning tunneling microscopy and cross-sectional imaging scanning transmission electron microscopy, which compare well to the proposed DLHC structure. The 2D AlSb exhibits a band gap of 0.93 eV versus the predicted 1.06 eV, which is substantially smaller than the 1.6 eV of bulk. We also attempt the less-stable InSb DLHC structure; however, it grows into bulk islands instead. The successful growth of a DLHC material here demonstrates the feasibility for the realization of a large family of 2D DLHC traditional semiconductors with characteristic excitonic, topological, and electronic properties.

8.
Chinese Herbal Medicines ; (4): 396-402, 2021.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-953637

ABSTRACT

Objective: Most of the studies on the herb Chuanxiong Rhizoma (CR) have focused on the L-arginine-nitric oxide (NO) pathway, but the nitrate-nitrite-NO (NO

9.
Zhongguo Gu Shang ; 33(8): 745-9, 2020 Aug 25.
Article in Chinese | MEDLINE | ID: mdl-32875766

ABSTRACT

OBJECTIVE: To explore the safety of classic Acupotomy in the treatment of carpal tunnel syndrome. METHODS: Twenty six adult specimens (15 males and 11 females), aged 60 to 95(82.54±6.94) years old, were selected from 10% formalin antiseptic fixation. There were 52 sides(two of them could not be tested). The study period was from November 2017 to May 2018. The specimens were collected from the body donation center of the school of basic medicine, Peking University. The operation of releasing the transverse carpal ligament on the human body specimen was simulated by the classic acupotomy, and the distance from the four points to the surrounding anatomical structure was measured to calculate the direct injury rate to the nerve and blood vessels, and the shortest distance between the acupotomy and the nerve and blood vessels was defined as ≥2 mm as safety. RESULTS: In the experimental operation, the direct injury rate of nerve and blood vessel was 14% and 12% respectively. There was significant difference in the rate of direct nerve injury between the four injection points (P<0.05). There was no significant difference in the rate of direct vascular injury between the four injection points (P>0.05). Among the four points, there was a statistically significant difference in the safety of nerves(P<0.05), and the safety of point 1 and point 3 of radial injection was higher than that of point 2 and point 4 of ulnar injection(P<0.05). There was significant difference in the safety of blood vessels between the four points(P<0.05), and the safety of radial point 1 was higher than that of ulnar point 2 and point 4 (P<0.05). CONCLUSION: The safety of the classic Acupotomy for carpal tunnel syndrome is related to the location of the needle entry point, and the safety of theradial proximal end of the needle is the highest.


Subject(s)
Acupuncture Therapy , Carpal Tunnel Syndrome , Adult , Aged , Aged, 80 and over , Female , Humans , Ligaments, Articular , Male , Median Nerve/injuries , Middle Aged , Needles , Wrist Joint
10.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-828213

ABSTRACT

OBJECTIVE@#To explore the safety of classic Acupotomy in the treatment of carpal tunnel syndrome.@*METHODS@#Twenty six adult specimens (15 males and 11 females), aged 60 to 95(82.54±6.94) years old, were selected from 10% formalin antiseptic fixation. There were 52 sides(two of them could not be tested). The study period was from November 2017 to May 2018. The specimens were collected from the body donation center of the school of basic medicine, Peking University. The operation of releasing the transverse carpal ligament on the human body specimen was simulated by the classic acupotomy, and the distance from the four points to the surrounding anatomical structure was measured to calculate the direct injury rate to the nerve and blood vessels, and the shortest distance between the acupotomy and the nerve and blood vessels was defined as ≥2 mm as safety.@*RESULTS@#In the experimental operation, the direct injury rate of nerve and blood vessel was 14% and 12% respectively. There was significant difference in the rate of direct nerve injury between the four injection points (0.05). Among the four points, there was a statistically significant difference in the safety of nerves(<0.05), and the safety of point 1 and point 3 of radial injection was higher than that of point 2 and point 4 of ulnar injection(<0.05). There was significant difference in the safety of blood vessels between the four points(<0.05), and the safety of radial point 1 was higher than that of ulnar point 2 and point 4 (<0.05).@*CONCLUSION@#The safety of the classic Acupotomy for carpal tunnel syndrome is related to the location of the needle entry point, and the safety of theradial proximal end of the needle is the highest.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Acupuncture Therapy , Carpal Tunnel Syndrome , Ligaments, Articular , Median Nerve , Wounds and Injuries , Needles , Wrist Joint
11.
Zhongguo Gu Shang ; 32(5): 479-484, 2019 May 25.
Article in Chinese | MEDLINE | ID: mdl-31248247

ABSTRACT

Stenosing tenosynovitis of styloid process of radius(de Quervain's disease) which abductor pollicis longus and extensor pollicis brevis in the first extensor chamber are affected by resistance when sliding, the incidence is affected by anatomical variations. Symptoms, signs and auxiliary examinations can diagnose the disease. Slight dQS can be improved by rest, brace, restriction activities, and oral medications. Chinese medicine and physiotherapy also reduce the disease. Needle knife therapy is a Traditional Chinese medicine minimally invasive surgery, which is also a step-by-step treatment between conservative treatment and open surgery to loosening the compression of the first extensor chamber. Steroid injection is a more common treatment in this disease, and its efficacy is related to the accuracy of the injection and is affected by the severity of the patient's anatomical variation. Identifying the spacing within the first extensor chamber under ultrasound can help patients better choose conservative or surgical treatment. Surgical treatment can more completely change the condition of dQD from anatomical structure, and clinical should pay attention to the choice of surgical procedure to improve the efficacy and reduce the occurrence of surgical complications. This article discusses the pathogenesis, diagnosis and treatment of the disease from the perspective of anatomical structure. It mainly analyzes the therapeutic targets and the clinical application, which aims to provide reference for the diagnosis and treatment of de Quervain disease.


Subject(s)
De Quervain Disease , Tendon Entrapment , Tenosynovitis , Humans , Radius , Wrist Joint
12.
Zhongguo Gu Shang ; 32(2): 130-135, 2019 Feb 25.
Article in Chinese | MEDLINE | ID: mdl-30884928

ABSTRACT

OBJECTIVE: To investigate the clinical characteristics and mechanism of cervicogenic headache. METHODS: Fifty-seven patients with cervicogenic headache who were treated from May 2013 to December 2017 and had complete imaging data were selected, including 18 males and 39 females with an average age of(43.26±10.39) years old ranging from 20 to 63 years old. The duration of the disease was 4 months to 35 years with a mean of (11.74±9.47) years. The pain situation, iconography and Tinel sign were analyzed. RESULTS: The patients with cervicogenic headache often had bilateral pain. The regions mainly concentrated in the temporal region, with occipital, head or orbit pains. The VAS scores decreased with the duration of the disease. There were many cases of disc herniation(91.30%), vertebral instability(73.91%), atlantoaxial displacement(56.52%), curvature change of cervicogenic vertebra(54.35%). The number of positive Tinel sign points was between 3 and 24 (13.58±5.8) per patient. The number and extent of Tinel sign were significantly different between the affected side and healthy side(P<0.05). C2,3 facet joints(92.98%), post mastoid(89.47%), occipital concavity(89.47%), C3,4 facet joints(84.21%), third occipital nerve(80.70%) were the positive Tinel sign points in patients with cervicogenic headache. CONCLUSIONS: The iconography changes of cervicogenic headache and Tinel sign may contribute to the clinical diagnosis and mechanism of the disease.


Subject(s)
Post-Traumatic Headache , Adult , Cervical Vertebrae , Female , Humans , Male , Middle Aged , Spinal Nerves , Young Adult
13.
J Colloid Interface Sci ; 533: 561-568, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30179834

ABSTRACT

Pervious photocatalysis application of nanostructured suspensions reveals high recombination rates of photogenerated electron-hole pairs, low recycling efficiency and secondary pollution problems. Herein, MoS2@CdS nanocomposites thin films on FTO (fluorine-doped tin oxide) substrates are fabricated using facile electrodeposition by decorating a layer of highly-active MoS2 cocatalyst on CdS film to optimize the interface modification. The hybrid film exhibits enhanced photoelectrocatalytic activity compared to pristine CdS film. The synthesized CdS exhibits a bandgap of 2.42 eV with the conduct band at ca. -0.25 V vs. RHE, while MoS2 reveals a bandgap of 1.73 eV with the valance band at ca. 1.59 V vs. RHE. The appropriate band alignment between the hybrid films favours the electrons transfer thus the charge recombination are suppressed. The MoS2@CdS film yields a highest photocurrent of 15.2 mA/cm2 at 0 V vs. Ag/AgCl under visible light illumination (λ ≧ 420 nm), exhibiting a 5.2 times enhancement as compared to that of CdS film (2.9 mA/cm2). The structural integration of MoS2 with CdS will be a promising strategy to develop a high-efficient and low-cost non-noble metal cocatalyst for solar energy conversion.

14.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-776124

ABSTRACT

OBJECTIVE@#To investigate the clinical characteristics and mechanism of cervicogenic headache.@*METHODS@#Fifty-seven patients with cervicogenic headache who were treated from May 2013 to December 2017 and had complete imaging data were selected, including 18 males and 39 females with an average age of(43.26±10.39) years old ranging from 20 to 63 years old. The duration of the disease was 4 months to 35 years with a mean of (11.74±9.47) years. The pain situation, iconography and Tinel sign were analyzed.@*RESULTS@#The patients with cervicogenic headache often had bilateral pain. The regions mainly concentrated in the temporal region, with occipital, head or orbit pains. The VAS scores decreased with the duration of the disease. There were many cases of disc herniation(91.30%), vertebral instability(73.91%), atlantoaxial displacement(56.52%), curvature change of cervicogenic vertebra(54.35%). The number of positive Tinel sign points was between 3 and 24 (13.58±5.8) per patient. The number and extent of Tinel sign were significantly different between the affected side and healthy side(<0.05). C₂,₃ facet joints(92.98%), post mastoid(89.47%), occipital concavity(89.47%), C₃,₄ facet joints(84.21%), third occipital nerve(80.70%) were the positive Tinel sign points in patients with cervicogenic headache.@*CONCLUSIONS@#The iconography changes of cervicogenic headache and Tinel sign may contribute to the clinical diagnosis and mechanism of the disease.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Young Adult , Cervical Vertebrae , Post-Traumatic Headache , Spinal Nerves
15.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-773894

ABSTRACT

Stenosing tenosynovitis of styloid process of radius(de Quervain's disease) which abductor pollicis longus and extensor pollicis brevis in the first extensor chamber are affected by resistance when sliding, the incidence is affected by anatomical variations. Symptoms, signs and auxiliary examinations can diagnose the disease. Slight dQS can be improved by rest, brace, restriction activities, and oral medications. Chinese medicine and physiotherapy also reduce the disease. Needle knife therapy is a Traditional Chinese medicine minimally invasive surgery, which is also a step-by-step treatment between conservative treatment and open surgery to loosening the compression of the first extensor chamber. Steroid injection is a more common treatment in this disease, and its efficacy is related to the accuracy of the injection and is affected by the severity of the patient's anatomical variation. Identifying the spacing within the first extensor chamber under ultrasound can help patients better choose conservative or surgical treatment. Surgical treatment can more completely change the condition of dQD from anatomical structure, and clinical should pay attention to the choice of surgical procedure to improve the efficacy and reduce the occurrence of surgical complications. This article discusses the pathogenesis, diagnosis and treatment of the disease from the perspective of anatomical structure. It mainly analyzes the therapeutic targets and the clinical application, which aims to provide reference for the diagnosis and treatment of de Quervain disease.


Subject(s)
Humans , De Quervain Disease , Radius , Tendon Entrapment , Tenosynovitis , Wrist Joint
16.
Chemistry ; 24(32): 8205-8216, 2018 Jun 07.
Article in English | MEDLINE | ID: mdl-29528515

ABSTRACT

A highly convergent and efficient strategy was developed for the chemical synthesis of complex oligosaccharides of Streptococcus pneumoniae type 3 capsular polysaccharides that contain multiple glucuronic acid units. Once the oligoglucosides were efficiently and stereoselectively assembled, the designated glucose units were regioselectively oxidized to glucuronic acid in one step at the final synthetic stage, which helped avoid difficult glycosylations that involved glucuronic acid. The target oligosaccharides had a free amino group at the reducing terminus and varied caps at the non-reducing terminus to enable further modification and structure-activity relationship studies. Immunological evaluations of the oligosaccharide-tetanus toxoid conjugates showed that they elicited robust T-cell-dependent immunoglobulin G antibody responses and that the sugar chain length had a major impact on their immunological properties. In particular, the penta- and hexasaccharides were identified as promising antigens for vaccine development.


Subject(s)
Bacterial Capsules/chemistry , Immunoglobulin G/immunology , Oligosaccharides/chemical synthesis , Polysaccharides, Bacterial/immunology , Streptococcus pneumoniae/chemistry , Tetanus Toxoid , Glycosylation , Oligosaccharides/chemistry , Polysaccharides, Bacterial/chemistry , Serogroup
17.
Oncotarget ; 8(21): 35061-35068, 2017 May 23.
Article in English | MEDLINE | ID: mdl-28456783

ABSTRACT

We have previously shown that Gαi3 is elevated in human glioma, mediating Akt activation and cancer cell proliferation. Here, we imply that Gαi3 could also be important for irradiation resistance. In A172 human glioma cells, Gαi3 knockdown (by targeted shRNAs) or dominant-negative mutation significantly potentiated irradiation-induced cell apoptosis. Reversely, forced over-expression of wild-type or constitutively-active Gαi3 inhibited irradiation-induced A172 cell apoptosis. Irradiation in A172 cells induced Gαi3 translocation to cell nuclei and association with local protein DNA-dependent protein kinase (DNA-PK) catalytic subunit. This association was important for DNA damage repair. Gαi3 knockdown, depletion (using Gαi3 knockout MEFs) or dominant-negative mutation potentiated irradiation-induced DNA damages. On the other hand, expression of the constitutively-active Gαi3 in A172 cells inhibited DNA damage by irradiation. Together, these results indicate a novel function of Gαi3 in irradiation-resistance in human glioma cells.


Subject(s)
Brain Neoplasms/metabolism , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism , Glioma/metabolism , Radiation Tolerance , Brain Neoplasms/genetics , Brain Neoplasms/radiotherapy , Cell Line, Tumor , Cell Nucleus/metabolism , DNA Damage , DNA-Activated Protein Kinase/metabolism , GTP-Binding Protein alpha Subunits, Gi-Go/genetics , Gene Expression Regulation, Neoplastic/radiation effects , Glioma/genetics , Glioma/radiotherapy , Humans , Protein Transport
18.
Oncotarget ; 8(1): 988-998, 2017 Jan 03.
Article in English | MEDLINE | ID: mdl-27894091

ABSTRACT

Here, we assessed the anti-colorectal cancer (CRC) cell activity of cinobufagin (CBG). We found that CBG exerted potent cytotoxic and anti-proliferative activity against CRC lines (HCT-116 and HT-29) and primary human CRC cells. Meanwhile, it activated apoptosis, and disrupted cell-cycle progression in the cells. At the signaling level, CBG treatment in CRC cells provoked endoplasmic reticulum stress (ER stress), the latter was evidenced by caspase-12 activation, CHOP expression, as well as PERK and IRE1 phosphorylations. Contrarily, the ER stress inhibitor salubrinal, the caspase-12 inhibitor and CHOP shRNA remarkably attenuated CBG-induced CRC cell death and apoptosis. Further, CBG in-activated mammalian target or rapamycin complex 1 (mTORC1), which appeared responsible for proliferation inhibition in CRC cells. Introduction of a constitutively-active S6K1 ("ca-S6K1") restored proliferation of CBG-treated CRC cells. Finally, CBG intraperitoneal injection suppressed HCT-116 xenograft tumor growth in the nude mice. CHOP upregulation and mTORC1 in-activation were also noticed in CBG-treated HCT-116 tumors. The results of this preclinical study suggest that CBG could be tested as promising anti-CRC agent.


Subject(s)
Antineoplastic Agents/pharmacology , Bufanolides/pharmacology , Animals , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Disease Models, Animal , Drug Evaluation, Preclinical , Endoplasmic Reticulum Stress/drug effects , Humans , Mechanistic Target of Rapamycin Complex 1/metabolism , Mice , Mice, Nude , Xenograft Model Antitumor Assays
19.
Org Biomol Chem ; 14(48): 11462-11472, 2016 Dec 28.
Article in English | MEDLINE | ID: mdl-27883156

ABSTRACT

An efficient synthesis of the 3-aminopropyl glycoside of the biological repeating unit of Streptococcus pneumoniae serotype 23F capsular polysaccharide (CPS) was accomplished. The synthetic target contained a tetrasaccharide with a phosphoglycerol branch. Its oligosaccharide backbone was assembled via linear glycosylation, and the challenging ß-rhamnosyl linkage in its structure was achieved stereospecifically through naphthylmethyl-assisted intramolecular aglycon delivery (IAD). The remaining 1,2-trans glycosylation reactions were executed in excellent yields and stereoselectivity based on neighboring group participation. The phosphoglycerol branch was installed by the phosphoramidite method with benzylidene-protected glycerol 2-phosphoramidite as the substrate. Eventually, the target molecule was synthesized from monosaccharide building blocks in 17 longest linear steps and a 3.85% overall yield. In addition, the synthetic target also contained a free amino group at its reducing end, facilitating its conjugation with other molecules for various biological studies and applications.


Subject(s)
Polysaccharides, Bacterial/chemical synthesis , Streptococcus pneumoniae/chemistry , Molecular Structure , Polysaccharides, Bacterial/chemistry , Serogroup
20.
Biochem Biophys Res Commun ; 479(1): 54-60, 2016 10 07.
Article in English | MEDLINE | ID: mdl-27614310

ABSTRACT

Dexamethasone (Dex) causes osteoblast cell injuries. In the present research, we tested the potential effect of SC79, a novel and specific Akt activator, against Dex in osteoblasts. In primary murine osteoblasts and osteoblastic MC3T3-E1 cells, pretreatment with SC79 significantly attenuated Dex-induced cell death. Further, Dex-induced mitochondrial permeability transition pore (mPTP) opening, cytochrome C release and apoptosis activation were dramatically alleviated with SC79 pretreatment in above cells. At the molecular level, SC79 activated Akt, which was indispensable for subsequent osteoblast protection against Dex. Akt inhibitors (LY294002, perifosine and MK-2206) blocked SC79-induced Akt activation and abolished its anti-Dex actions in osteoblasts. Further, SC79 activated Akt downstream Nrf2 (NF-E2-related factor 2) signaling and attenuated Dex-induced oxidative stress in osteoblasts. Nrf2 shRNA knockdown or S40T mutation almost reversed SC79-mediated anti-oxidant and cytoprotective activities in osteoblasts. Together, these results suggest that SC79 activates Akt-Nrf2 signaling to protect osteoblasts from Dex.


Subject(s)
Acetates/pharmacology , Benzopyrans/pharmacology , Dexamethasone/pharmacology , NF-E2-Related Factor 2/metabolism , Osteoblasts/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Animals , Animals, Newborn , Anti-Inflammatory Agents/pharmacology , Apoptosis/drug effects , Apoptosis/genetics , Blotting, Western , Cell Line , Cells, Cultured , Cytochromes c/metabolism , Gene Expression/drug effects , Heterocyclic Compounds, 3-Ring/pharmacology , Humans , Mice , Mitochondrial Membrane Transport Proteins/metabolism , Mitochondrial Permeability Transition Pore , Mutation , NF-E2-Related Factor 2/genetics , Osteoblasts/cytology , Osteoblasts/metabolism , Oxidative Stress/drug effects , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/genetics
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