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1.
Neurosci Lett ; 820: 137592, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38103631

RESUMO

Despite affecting over 1.5 billion people globally, hearing loss (HL) has been referred to as an "invisible disability", with noise exposure being a major causative factor. Accumulating evidence suggests that HL can induce cognitive impairment. However, relatively little is known about the effects of noise-induced hearing loss (NIHL) on social memory. This study aimed to further investigate the effect of NIHL on social behaviours in mice. We established a rodent model of NIHL using 4-week-old C57BL/6J mice who experienced narrow noise exposure at 116 dB for 3 h per day over two consecutive days. Hearing ability was subsequently evaluated through auditory brainstem response (ABR) testing, and potential changes in the morphology of cochlear hair cells were assessed using immunofluorescence. The sociability and social memory of the mice were evaluated using the three-chamber social interaction test. Noise exposure resulted in complete and persistent HL in C57BL/6J mice, accompanied by severe loss of cochlear hair cells. More importantly, social memory was impaired in adult NIHL mice, whereas their sociability remained intact, these changes were accompanied by a decrease in the protein levels of the inhibitory neuron marker glutamic acid decarboxylase 67 (GAD67) in the ventral hippocampus. This study is the first to confirm that long-term auditory deprivation from HL induced by noise exposure results in social memory deficits in mice without altering their sociability.


Assuntos
Perda Auditiva Provocada por Ruído , Humanos , Adulto , Animais , Camundongos , Perda Auditiva Provocada por Ruído/metabolismo , Camundongos Endogâmicos C57BL , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Hipocampo/metabolismo , Transtornos da Memória/etiologia , Neurotransmissores/farmacologia , Limiar Auditivo/fisiologia , Cóclea/metabolismo
2.
Chinese Journal of Endemiology ; (12): 269-273, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991618

RESUMO

Objective:To observe multiple locus variable-number tandem repeat analysis (MLVA) typing of Brucella isolated from Himalayan marmot in Qinghai-Tibet Plateau of Qinghai Province, and to explore the relationship between the strains and strains previous isolated from Qinghai Province. Methods:Blood samples of Himalayan marmot were collected in Qinghai-Tibet Plateau of Qinghai Province from March 2019 to October 2020. Pathogens were isolated and cultured from Brucella antibody positive samples identified by using the rose bengal test (RBT). Conventional biological methods and molecular biological methods (BCSP31-PCR and AMOS-PCR) were used for strain identification. At the same time, MLVA method was used to genotype the isolated strains, and cluster analysis was used to analyze the genetic relationships between the strains based on the genotype of 70 Brucella isolated from different hosts in Qinghai Province. Results:A total of 1 466 blood samples of Himalayan marmot were collected from Qinghai-Tibet Plateau. Two strains of Brucella were isolated and cultured from 64 RBT-positive samples, named QH2013054 and QH2013062, respectively. They were identified as Brucella ovis biotype Ⅲ by conventional and molecular biological methods. The MLVA genotyping results showed that QH2013054 and QH2013062 were different at the Bru16 locus, indicating different MLVA genotypes. Cluster analysis showed that strain QH2013054 had the same MLVA genotype as 7 strains, among which 6 strains were from 3 farmers and 3 sheep from the same family in Gonghe County, and 1 strain was from a farmer in Menyuan Hui Autonomous County. The strain QH2013062 had the same MLVA genotype as 4 strains, including 3 strains from 3 farmers in Menyuan Hui Autonomous County and 1 strain from a farmer in Tu Autonomous County of Huzhu. Conclusions:The strains of Brucella isolated from Himalayan marmot in Qinghai-Tibet Plateau of Qinghai Province have the same MLVA genotype as some strains of Brucella isolated from humans and sheep in Qinghai Province. It is speculated that the host humans, sheep and Himalayan marmot in Qinghai-Tibet Plateau may have a common source of infection.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991572

RESUMO

Objective:To learn about the genotyping of human Brucella isolated from Sichuan Province. Methods:BCSP31-PCR and AMOS-PCR were used to identify the genus and biotype of the 66 strains isolated from confirmed human brucellosis cases in Sichuan Province from 2014 to 2020, respectively. The isolated strains were genotyped by multi-locus sequence typing (MLST)-9. The sequence type (ST) was compared trough the online MLST database. A minimum spanning tree (MST) was constructed to cluster the newly discovered and known ST using the BioNumerics software version 7.6.Results:The 66 strains isolated from human cases of brucellosis in Sichuan Province from 2014 to 2020 were Brucella, and 65 of them were Brucella melitensis while one strain was Brucella abortus. The MLST method identified three known STs (ST-8, ST-39 and ST-2) and one newly type (ST-101). Among them, ST-8 was the main ST in Sichuan Province (90.91%, 60/66), another 4 strains of Brucella melitensis were ST-39, and 1 strain of Brucella abortus was ST-2. The newly type ST-101 was isolated from Leshan City in 2019, belonging to the Brucella melitensis and closely related to the evolution of ST-8. Conclusion:Brucella melitensis is the main epidemic Brucella strain in Sichuan Province, ST-8 is predominant genotype, with a small amount of ST-39, ST-101 and ST-2.

4.
Front Mol Neurosci ; 15: 1031278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518186

RESUMO

Cochlear ribbon synapses formed between spiral ganglion neurons and inner hair cells in postnatal mice must undergo significant morphological and functional development to reach auditory maturation. However, the mechanisms underlying cochlear ribbon synapse remodeling remain unclear. This study found that cochlear resident macrophages are essential for cochlear ribbon synapse development and maturation in mice via the CX3CR1/CX3CL1 axis. CX3CR1 expression (a macrophage surface-specific receptor) and macrophage count in the cochlea were significantly increased from postnatal day 7 then decreased from days 14 to 28. Seven-day treatment with CX3CR1 inhibitors and artificial upregulation of CX3CL1 levels in the inner ear environment using the semicircular canal injection technique were initiated on day 7, and this resulted in a significant increase in hearing threshold on day 28. Additionally, abnormalities in the morphology and number of cochlear ribbon synapses were detected on day P14, which may be associated with hearing impairment. In conclusion, macrophage regulation of cochlear ribbon synapse remodeling via the CX3CR1/CX3CL1 axis is required during hearing development and offers a new perspective on immune-related hearing loss throughout auditory development. Importantly, it could be a new treatment target for sensorineural hearing loss.

5.
Polymers (Basel) ; 14(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36236185

RESUMO

Phenolic-matrix composites possess excellent synergistic effects on mechanical and tribological properties and can be used in the aerospace, medical, and automobile industries. In this work, a series of phenol-formaldehyde resin/hexagonal boron nitride nanocomposites (PF/BNs) were in situ synthesized using an easy method. PF/BN coatings (PF/BNCs) on 316L steels were prepared through a spin-casting method. The wear behaviors of these PF/BNCs were investigated by dry sliding with steel balls. The percentage of BN, the thickness of the coating, and the heat treatment temperature affected the coefficients of friction (COFs) and wear rates of these coatings. After heat treatment at 100 °C, the tribological properties of the PF/BNCs were remarkably improved, which might be attributed to both the transformation of carbon on the worn surfaces from C-O/C=O into C=N, carbide, and other chemical bonds and the cross-linking of the prepolymers.

6.
World J Clin Cases ; 10(12): 3951-3958, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35647138

RESUMO

BACKGROUND: Infectious mononucleosis (IM) is a disease caused by Epstein-Barr virus (EBV). EBV infection is common in children; however, it can cause IM in adults. Studies on recurrence of IM in adults after remission are limited. CASE SUMMARY: We report a 28-year-old man who presented with IM-like symptoms with mild liver damage after initial remission of IM for 3 years. He was first diagnosed with IM and treated in 2015. Follow-up tests in 2016 and 2017 did not show any abnormalities. In November 2018, he presented with swelling of the tonsils. He was misdiagnosed with acute suppurative tonsillitis and treated for 5 d. No signs of improvement were observed. He was readmitted with recurrent fever, pharyngalgia, fatigue, and systemic muscle pain. Examinations revealed enlargement of the tonsils and cervical lymph nodes. Blood tests revealed elevated transaminase levels. Anti-EBV test was positive, indicating virus reactivation. IM recurrence was confirmed on the basis of laboratory tests and clinical manifestations. He was treated with antiviral, anti-infective, and hepatoprotective drugs and vitamin supplements. His condition improved and no abnormalities were observed during follow-up. CONCLUSION: Recurrence of IM after remission is possible in adults; therefore, long-term follow-up and monitoring are essential.

7.
J Neurosci Methods ; 378: 109641, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35688295

RESUMO

BACKGROUND: Cochlear ablation is one of the most classic methods for the animal model establishment of hearing loss (HL), but the vast majority of rodents taken by cochlear ablation have been rats and adult mice so far. Given the importance of mice in HL studies, it is urgently necessary to expand the application of cochlear ablation in mice at different ages. NEW METHOD: Bilateral cochlear ablation surgery was performed in C57BL/6 J mice before the onset of hearing at postnatal (P) day 10. Auditory brainstem response was performed to evaluate the hearing of mice. Open field test and swimming test were performed to examine the vestibular function of mice. RESULTS: A permanent HL model was built by bilateral cochlear ablation in C57BL/6 J mice at P10. This method could successfully destroy cochlear hair cells and cause no vestibular deterioration in the adulthood of mice. COMPARISON WITH EXISTING METHOD(S): In addition to transgenic mice, permanently deaf mice used in this field in the existing studies are restricted to a time point after their ear canal opening. This study is the first to establish a congenital and permanent HL mouse model by cochlear ablation without gene modification. CONCLUSIONS: Bilateral cochlear ablation in mice at P10 is an ideal and effective way for congenital HL mice model foundation, and the vestibular function seems not to be deteriorated.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Animais , Cóclea/cirurgia , Modelos Animais de Doenças , Audição/fisiologia , Perda Auditiva Neurossensorial/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos
8.
Asian J Androl ; 24(5): 525-532, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35042311

RESUMO

Primary signet ring cell carcinoma (SRCC) of the prostate is a rare neoplasm. However, its potential tumorigenic mechanism, clinicopathological features, and prognostic outcome have not been systematically described. To determine the pathogenic mechanism, we detected distributions of programmed cell death-ligand 1 (PD-L1), programmed death 1 (PD-1), and cellular components in the tumor microenvironment, including tumor-infiltrating lymphocytes (CD4 and CD8), tumor-associated macrophages (TAMs; CD163 and CD68), and tumor-associated fibroblasts (vimentin and alpha-smooth muscle actin [α-SMA]), in tumor tissues from four patients with primary prostatic SRCC compared with corresponding adjacent tissues and tumor tissues from 30 patients with prostate adenocarcinoma (PCa) by immunohistochemical staining. We found higher expression of PD-L1, CD163, and CD68 in primary SRCC specimens than that in both corresponding adjacent nontumor specimens and PCa specimens with different Gleason scores, indicating that TAMs may participate in the malignant biological behavior of primary SRCC of the prostate. For further analysis, we searched electronic journal databases and Surveillance, Epidemiology, and End Results (SEER) to identify 200 eligible patients including our four cases. According to Kaplan-Meier survival curve analysis, patients <68 years old, with radical prostatectomy (RP), Gleason score of 7-8, and lower clinical stage had longer overall survival (OS). Moreover, Cox multivariate analysis indicated that race (hazard ratio [HR] = 1.422), surgical approach (HR = 1.654), and Gleason score (HR = 2.162) were independent prognostic factors for OS. Therefore, primary SRCC of the prostate represents a distinct and aggressive subtype of prostate cancer associated with a higher distribution of PD-L1 and TAMs, which warrants further clinical investigation.


Assuntos
Carcinoma de Células em Anel de Sinete , Neoplasias da Próstata , Idoso , Antígeno B7-H1 , Humanos , Linfócitos do Interstício Tumoral , Masculino , Prognóstico , Próstata , Microambiente Tumoral
9.
Asian J Surg ; 45(2): 718-724, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34426062

RESUMO

INTRODUCTION: To analyze the clinicopathological characteristics, immunohistochemistry, genotyping and prognosis of patients in the multicenter GIST data in Inner Mongolia, China. METHODS: Retrospective analysis was performed on GIST data from January 2013 to January 2018 in Inner Mongolia. Descriptive statistics were used to analyze the clinical characteristics of GIST patients. The Chi-square test was performed on the modified NIH criteria by age distribution, and Kaplan-Merie method was used for survival analysis. RESULTS: A total of 804 patients were included in the GIST database in Inner Mongolia, with a male to female ratio of 1.1102:1. The most common location was the gastric (465). Mitotic count ≤5/50HPFs was found in 67.3 % patients. There were 276 patients with tumor diameter of 2-5 cm and 354 patients with tumor diameter of 5.1-10 cm.The modified NIH criteria was mainly of intermediate risk (210) and high risk (342). The recurrence and metastasis of patients were related to the tumor location, mitotic index, tumor size, and modified NIH criteria. All patients were followed up for 1-10 years, in which 63.1 % of them were followed up for at least three years. The 3-year survival rates of patients with modified NIH criteria of very low risk, low risk, intermediate risk, and high risk were 100 %, 100 %, 100 %, and 96.3 %, respectively. CONCLUSIONS: The incidence of GIST in middle-aged and elder people in Inner Mongolia is high, and the long-term prognosis of patients after surgical treatment is good, which can objectively reflect the incidence, diagnosis and treatment of GIST in Inner Mongolia.


Assuntos
Tumores do Estroma Gastrointestinal , Idoso , China/epidemiologia , Feminino , Tumores do Estroma Gastrointestinal/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
10.
Zhongguo Gu Shang ; 34(12): 1158-64, 2021 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-34965635

RESUMO

OBJECTIVE: To explore the clinical efficacy of focused extracorporeal shock wave therapy with centrifugal exercise in the treatment of greater trochanteric pain syndrome. METHODS: From September 2017 to June 2019, 53 eligible cases of greater trochanteric pain syndrome were randomly divided into observation group (29 cases) and control group (24 cases). In observation group, there were 8 males and 21 females, aged from 38 to 62 years old with an average of (49.96±6.39) years old; the course of disease ranged from 6 to 13 months with an average of (8.58±1.99) months;treated with focused extracorporeal shock wave therapy with centrifugal exercise. In control group, there were 5 males and 19 females, aged from 39 to 62 years old with an average of (52.79±5.86) years old;the course of disease ranged from 6 to 14 months with an average of (9.04±2.51) months;treated with centrifugal exercise alone. Visual analogue scale (VAS) and hip Harris score were measured before ESWT treatment and at 1, 2, and 6 months to evaluate relieve degree of pain and functional recovery of hip joint, respectively. RESULTS: At 1 month after treatment, there were no significant differences in VAS, hip Harris score and treatment success rate (all P>0.05). At 2 months after treatment, VAS score in observation group (3.20±0.81) was lower than that of control group (3.87±0.61, P=0.002), there were no significant differences in hip Harris score score between observation group (81.93±2.43) and control group (82.12±2.34, P=0.770), the treatment success rate in observation group (58.62%, 17 / 29) was higher than that of control group (29.16%, 7 / 24) (P=0.032). At 6 months after treatment, VAS score in observationgroup (2.24±0.68) was lower than that of control group (3.12±0.53, P<0.001), hip Harris score score in observation group(85.10±1.75) was higher than that of control group (83.66±1.78)(P=0.005), there were no significant differences in treatment success rate between observation group (82.75%, 24 / 29) and control group (62.50%, 15 / 24)(P=0.096). CONCLUSION: In treatment of greater trochanteric pain syndrome, focused extracorporeal shock wave therapy with centrifugal exercise could significantly relieve symptoms of lateral hip pain, improve functional recovery of hip joint with good safety. This treatment strategy is worthy of application and promotion in clinical practice.


Assuntos
Bursite , Tratamento por Ondas de Choque Extracorpóreas , Adulto , Artralgia , Feminino , Quadril , Articulação do Quadril , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
Materials (Basel) ; 14(20)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34683779

RESUMO

There are still many unsolved mysteries in the thermal decomposition process of urea. This paper studied the thermal decomposition process of urea at constant temperatures by the thermal gravimetric-mass spectrometry analysis method. The results show that there are three obvious stages of mass loss during the thermal decomposition process of urea, which is closely related to the temperature. When the temperature was below 160 °C, urea decomposition almost did not occur, and molten urea evaporated slowly. When the temperature was between 180 and 200 °C, the content of biuret, one of the by-products in the thermal decomposition of urea, reached a maximum. When the temperature was higher than 200 °C, the first stage of mass loss was completed quickly, and urea and biuret rapidly broke down. When the temperature was about 240 °C, there were rarely urea and biuret in residual substance; however, the content of cyanuric acid was still rising. When the temperature was higher than 280°C, there was a second stage of mass loss. In the second stage of mass loss, when the temperature was higher than 330 °C, mass decreased rapidly, which was mainly due to the decomposition of cyanuric acid. When the temperature was higher than 380 °C, the third stage of mass loss occurred. However, when the temperature was higher than 400 °C, and after continuous heating was applied for a sufficiently long time, the residual mass was reduced to almost zero eventually.

12.
IEEE J Biomed Health Inform ; 25(10): 3834-3843, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34170835

RESUMO

Recently, the state-of-the-art performance in various sensor based human activity recognition (HAR) tasks have been acquired by deep learning, which can extract automatically features from raw data. In order to obtain the best accuracy, many static layers have been always used to train deep neural networks, and their weight connectivity in network remains unchanged. Pursuing the best accuracy in mobile platforms with a very limited computational budget at millions of FLOPs is impractical. In this paper, we make use of shallow convolutional neural networks (CNNs) with channel-selectivity for the use of HAR. As we have known, it is for the first time to adopt channel-selectivity CNN for sensor based HAR tasks. We perform extensive experiments on 5 public benchmark HAR datasets consisting of UCI-HAR dataset, OPPORTUNITY dataset, UniMib-SHAR dataset, WISDM dataset, and PAMAP2 dataset. As a result, the channel-selectivity can achieve lower test errors than static layers. The existing performance of deep HAR can be further improved by the CNN with channel-selectivity without any extra cost.


Assuntos
Atividades Humanas , Redes Neurais de Computação , Humanos
13.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1783-1790, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042374

RESUMO

Root exudates are important carriers for material exchange and information transfer between plant and soil, and important regulators of crop-soil-microorganism interaction in intercropping systems. We examined the interaction between crops in intercropping system by setting three treatments, monoculture Chinese milk vetch, monoculture rape and Chinese milk vetch intercropped with rape. The responses of root exudates were emphatically analyzed. The results showed that 391 root exudates were detected, with 93 of which being identified and divided into nine types of metabo-lites. Among them, organooxygen compounds were the most abundant, mainly in the form of ribitol. Under different planting patterns, root exudates of Chinese milk vetch and rape were significantly different. The characteristics of root exudates in intercropping were similar to monoculture rape, but significantly different from monoculture Chinese milk vetch. Among the root exudates in different planting modes, only 9-fluorenone 1 was negatively correlated with others. The differential root exudates were mainly benzenoids, lipids and lipid-like molecules, organic acids and derivatives, and organooxygen compounds. The benzenoids, lipids and lipid-like molecules were important types that characterized the changes of root exudates of Chinese milk vetch and rape. Chinese milk vetch intercropping with rape changed the characteristics of root exudates, which were closely related to benzenoids, lipids, and lipid-like molecules.


Assuntos
Astrágalo , Estupro , Agricultura , China , Exsudatos e Transudatos , Solo
14.
J Fluoresc ; 31(3): 807-815, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33725275

RESUMO

Two triphenylamine chalcone derivatives 1 and 2 were synthesized through the Vilsmeier-Haack reaction and Claisen-Schmidt condensation reaction. Through ultraviolet absorption spectroscopy and fluorescence emission spectroscopy experiments, it was confirmed that these two compounds exhibited good aggregation-induced emission (AIE) behavior in ethanol/water mixtures. The solvent effect test showed with the increase of the orientation polarizability of the solvent, the Stokes shift in the solvent of compound 1 and compound 2 shows a linear change trend. Through solid state fluorescence test and universal density function theory (DFT), the existence of π-π stacking interaction in the solid state of the compound has been studied, resulting in weak fluorescence emission. pH has no effect on the fluorescence intensity of the aggregate state of excited state intramolecular proton transfer (ESIPT) molecules in an acidic environment, but greatly weakens its fluorescence intensity in an alkaline environment. Cyclic voltammetry (CV) test shows that compound 1 was more prone to oxidation reaction than compound 2. The results of thermal stability test show that the thermal stability of compound 1 was better than that of compound 2, indicating that triphenylamine chalcone derivatives can improve the thermal stability of compounds by increasing the number of branches.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-921942

RESUMO

OBJECTIVE@#To explore the clinical efficacy of focused extracorporeal shock wave therapy with centrifugal exercise in the treatment of greater trochanteric pain syndrome.@*METHODS@#From September 2017 to June 2019, 53 eligible cases of greater trochanteric pain syndrome were randomly divided into observation group (29 cases) and control group (24 cases). In observation group, there were 8 males and 21 females, aged from 38 to 62 years old with an average of (49.96±6.39) years old; the course of disease ranged from 6 to 13 months with an average of (8.58±1.99) months;treated with focused extracorporeal shock wave therapy with centrifugal exercise. In control group, there were 5 males and 19 females, aged from 39 to 62 years old with an average of (52.79±5.86) years old;the course of disease ranged from 6 to 14 months with an average of (9.04±2.51) months;treated with centrifugal exercise alone. Visual analogue scale (VAS) and hip Harris score were measured before ESWT treatment and at 1, 2, and 6 months to evaluate relieve degree of pain and functional recovery of hip joint, respectively.@*RESULTS@#At 1 month after treatment, there were no significant differences in VAS, hip Harris score and treatment success rate (all @*CONCLUSION@#In treatment of greater trochanteric pain syndrome, focused extracorporeal shock wave therapy with centrifugal exercise could significantly relieve symptoms of lateral hip pain, improve functional recovery of hip joint with good safety. This treatment strategy is worthy of application and promotion in clinical practice.


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artralgia , Bursite , Tratamento por Ondas de Choque Extracorpóreas , Quadril , Articulação do Quadril , Resultado do Tratamento
16.
Angew Chem Int Ed Engl ; 59(6): 2220-2224, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31749244

RESUMO

A rhodium(I)-BINAP-catalyzed highly enantioselective [2+2+2] cycloaddition of enynes with alkynes has been developed. Diverse fused tricyclic hydronaphthofuran scaffolds with three consecutive stereogenic centers were constructed in one step from easily available materials with excellent chemo-, regio-, diastereo-, and enantioselectivity. Notable features of these reactions include 100 % atom economy, very broad scope, and mild reaction conditions.

17.
Chem Sci ; 10(28): 6863-6867, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31391909

RESUMO

A rhodium-catalyzed highly regio- and enantioselective hydroalkynylation, generating cis-hydrobenzofuranone-tethered enynes has been developed. The reaction proceeds with a selective head-to-head insertion and symmetry breaking Michael addition cascade. One product was produced from tens of possible isomers through precise control of chemo-, regio-, and stereoselectivities using a single rhodium catalyst. Notable features of this method include 100% atom-economy, mild reaction conditions and a very broad substrate scope.

18.
Org Lett ; 21(3): 692-695, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30633533

RESUMO

With the synergistic activation of alkynyl alcohols and alkynyl enones by a single gold catalyst, diverse multisubstituted spirocyclopenta[ c]furans were synthesized in good to excellent yields under mild conditions. Three rings were constructed efficiently in one pot from easily available acyclic starting materials.

19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-751042

RESUMO

Objective @#To explore the discovery and treatment of multiple root canals in the maxillary second premolar to provide a reference for root canal therapy.@*Methods @#A case of maxillary second premolar occlusal discomfort accompanied by cold and heat stimulation pain and spontaneous pain was analyzed retrospectively.@*Results@# In this case, the number of roots and root canals in the tooth was determined by CBCT to be three roots with four canals. Root canal therapy was performed with Ni-Ti endodontic files and thermoplastic gutta-percha via root optical microscopy. The clinical symptoms disappeared after the operation.@*Conclusion@#The maxillary second premolar root canal system is complex, and additional root canals can be found and located with CBCT and optical microscopy. High-quality root canal therapy was completed.

20.
Chinese Journal of Zoonoses ; (12): 784-788, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-659529

RESUMO

The aim of the research is to investigate the genetic characteristics of Legionella pneumophila serogroup1 (LP1)in Sichuan Province.The sequence-based typing (SBT) and multiple-locus VNTR analysis (MLVA) were used to describe the genetic polymorphism of 42 strains which were isolated from 1989-2016 in Sichuan Province,China.According to the reference,PCR was used to detect the 8-VNTR loci and 7 housekeeping genes respectively.The VNTR results were determined by using capillary electrophoresis,and the SBT results were sequenced and compared with the database of EWGLI.Results showed that totally 42 stains were divided into 8 MLVA types with the advantage types were M08 (47.6 %) and M07 (23.8 %).Twelve ST types were obtained with 3 main clonal complex and 2 singleton,including 2 novel ST types,among those,ST1 was the predominant type,accounting for 52.3 %,following by ST630 (14.2 %).In conclusion,our results demonstrated MLVA and SBT were both applied to the research for molecular epidemiological investigation of LP1 and showed the high genetic polymorphism and the regional specificity.The results also suggest that the isolates are a potential threat to the public,effective control and prevention strategies are urgently needed.

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