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1.
Org Biomol Chem ; 19(3): 635-644, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33367392

RESUMO

A palladium-catalyzed redox-neutral allylic alkylation of indoles with cyclopropyl acetylenes has been disclosed. Various 1,3-diene indolenine framework bearing a quaternary stereocenter at the C3 position were synthesized straightforwardly in good to excellent yields with high regio- and stereoselectivities. The reaction could be further expanded to the dearomatization of naphthols to synthesize functionalized cyclohexadienones with 1,3-diene motifs. The reaction exhibited high atom economy and good functional group tolerance.

2.
Cell Physiol Biochem ; 51(5): 2275-2289, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30537735

RESUMO

BACKGROUND/AIMS: Parkinson's disease (PD) is a frequently occurring condition that resulted from the loss of midbrain neurons, which synthesize the neurotransmitter dopamine. In this study, we established mouse models of PD to investigate the expression of microRNA-128 (miR-128) and mechanism through which it affects apoptosis of dopamine (DA) neurons and the expression of excitatory amino acid transporter 4 (EAAT4) via binding to axis inhibition protein 1 (AXIN1). METHODS: Gene expression microarray analysis was performed to screen differentially expressed miRNAs that are associated with PD. The targeting relationship between miR-128 and AXIN1 was verified via a bioinformatics prediction and dual-luciferase reporter gene assay. After separation, DA neurons were subjected to a series of inhibitors, activators and shRNAs to validate the mechanisms of miR-128 in controlling of AXIN1 in PD. Positive protein expression of AXIN1 and EAAT4 in DA neurons was determined using immunocytochemistry. miR-128 expression and the mRNA and protein levels of AXIN1 and EAAT4 were evaluated via RT-qPCR and Western blot analysis, respectively. DA neuron apoptosis was evaluated using TUNEL staining. RESULTS: We identified AXIN1 as an upregulated gene in PD based on the microarray data of GSE7621. AXIN1 was targeted and negatively mediated by miR-128. In the DA neurons, upregulated miR-128 expression or sh-AXIN1 increased the positive expression rate of EAAT4 together with mRNA and protein levels, but decreased the mRNA and protein levels of AXIN1, apoptosis rate along with the positive expression rate of AXIN1; however, the opposite trend was found in response to transfection with miR-128 inhibitors. CONCLUSION: Evidence from experimental models revealed that miR-128 might reduce apoptosis of DA neurons while increasing the expression of EAAT4 which might be related to the downregulation of AXIN1. Thus, miR-128 may serve as a potential target for the treatment of PD.


Assuntos
Proteína Axina/genética , Neurônios Dopaminérgicos/patologia , Transportador 4 de Aminoácido Excitatório/genética , Regulação da Expressão Gênica , MicroRNAs/genética , Doença de Parkinson/genética , Animais , Apoptose , Neurônios Dopaminérgicos/metabolismo , Redes Reguladoras de Genes , Humanos , Masculino , Camundongos Endogâmicos C57BL , Doença de Parkinson/patologia , Regulação para Cima
3.
J Basic Microbiol ; 56(7): 753-61, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26422794

RESUMO

In this study, a superoxide dismutase gene (PsSOD) from Pseudoalteromonas sp. ANT506 was cloned and over expressed in Escherichia coli. The PsSOD has an open reading frame of 582 bp with a putative product of 193 amino acid residue and an estimated molecular size of 21.4 kDa. His-tagged PsSOD was subsequently purified 12.6-fold by Ni-affinity chromatography and the yield of 22.9%. The characterization of the purified rPsSOD exhibited maximum activity at 30 °C and pH 8.0. The enzyme exhibited 13.9% activity at 0 °C and had high-thermo lability at higher than 50 °C. rPsSOD exhibited well capability to 2.5 M NaCl (62.4%). These results indicated that rPsSOD exhibited special catalytic properties.


Assuntos
Proteínas de Bactérias/genética , Escherichia coli/genética , Pseudoalteromonas/enzimologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Sequência de Aminoácidos , Regiões Antárticas , Catálise , Clonagem Molecular , Escherichia coli/metabolismo , Peróxido de Hidrogênio/química , Fases de Leitura Aberta/genética , Pseudoalteromonas/genética , Pseudoalteromonas/metabolismo , Alinhamento de Sequência
4.
J Org Chem ; 79(3): 1084-92, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24393026

RESUMO

We report a novel molecular iodine-catalyzed 1,3-dipolar cycloaddition/oxidation/aromatization cascade process with hydrogen peroxide as the terminal oxidant for the construction of pyrrolo[2,1-a]isoquinolines. The product pyrrolo[2,1-a]isoquinolines were obtained from reactions between simple, readily available dipolarophiles and tetrahydroisoquinolines in moderate to excellent yields without the need for a metal catalyst.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(1): 197-201, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38387921

RESUMO

OBJECTIVE: To investigate the relationship between mutated genes and clinical features in patients with essential thrombocythemia (ET). METHODS: The clinical data of 69 patients with ET from October 2018 to March 2022 were retrospectively analyzed. According to driver mutation type, patients were divided into JAK2 group, CALR group and triple-negative group. The sex, age, cardiovascular risk factors, thrombosis, splenomegaly, routine blood test and coagulation status of patients in three groups were analyzed. RESULTS: Among 69 ET patients, 46 cases were associated with JAK2 mutation, 14 cases with CALR mutation, 8 cases with triple-negative mutation, and one with MPL gene mutation. There were no significant differences in age and sex among the three groups (P >0.05). The highest thrombotic rate was 26.09% (12/46) in JAK2 group, then 12.5% (1/8) in triple-negative group, while no thrombotic events occurred in CALR group. The incidence of splenomegaly was the highest in JAK2 group (34.78%), while no splenomegaly occurred in triple-negative group. The white blood cell (WBC) count in JAK2 group was (9.00±4.86)×109/L, which was significantly higher than (6.03±2.32)×109/L in CALR group (P <0.05). The hemoglobin (Hb) and hematocrit (HCT) in JAK2 group were (148.42±18.79) g/L and (0.44±0.06)%, respectively, which were both significantly higher than (131.00±15.17) g/L and (0.39±0.05)% in triple-negative group (P <0.05). The platelet (PLT) in JAK2 group was (584.17±175.77)×109/L, which was significantly lower than (703.07±225.60)×109/L in CALR group (P <0.05). The fibrinogen (Fg) in JAK2 and triple-negative group were (2.64±0.69) g/L and (3.05±0.77) g/L, respectively, which were both significantly higher than (2.24±0.47) g/L in CALR group (P <0.05, P <0.01). The activated partial thromboplastin time (APTT) in triple-negative group was (28.61±1.99) s, which was significantly decreased compared with (31.45±3.35) s in CALR group (P <0.05). CONCLUSIONS: There are differences in blood cell count and coagulation status among ET patients with different driver gene mutations. Among ET patients, JAK2 mutation is most common. Compared with CALR group, the thrombotic rate, WBC and Fg significantly increase in JAK2 group, while PLT decrease. Compared with triple-negative group, the incidence of splenomegaly and HCT significantly increase. Compared with CALR group, Fg significantly increases but APTT decreases in triple-negative group.


Assuntos
Trombocitemia Essencial , Trombose , Humanos , Calreticulina/genética , Janus Quinase 2/genética , Mutação , Estudos Retrospectivos , Esplenomegalia/complicações , Trombocitemia Essencial/genética , Trombocitemia Essencial/complicações
6.
J Org Chem ; 78(18): 9424-30, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23977993

RESUMO

An I2-induced 1,3-dipolar cycloaddition reaction has been developed for the synthesis of benzo[f]isoindole-1,3-dicarboxylates from quinones and N-substituted amino esters. The reaction proceeds in good to excellent yields in one step from 3 equiv of amino ester to react with the quinone structure. The utility of this transformation has been highlighted by its use for the construction of benzo[f]isoindole-1,3-dicarboxylates, which have been identified in natural products exhibiting important biological activities.


Assuntos
Ácidos Carboxílicos/química , Iodo/química , Isoindóis/síntese química , Ciclização , Isoindóis/química , Estrutura Molecular
7.
Arch Pharm (Weinheim) ; 346(5): 349-58, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23585245

RESUMO

A series of 3-aryl-4-pyrrolyl-maleimides were designed, synthesized, and evaluated for their glycogen synthase kinase-3ß (GSK-3ß) inhibitory activity. Most compounds exhibited potent activity against GSK-3ß. Among them, compounds 11a, 11c, 11h, 11i, and 11j significantly reduced Aß-induced Tau hyperphosphorylation, showing the inhibition of GSK-3ß at the cellular level. Structure-activity relationships were discussed based on the experimental data obtained.


Assuntos
Inibidores Enzimáticos/farmacologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Maleimidas/farmacologia , Linhagem Celular Tumoral , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glicogênio Sintase Quinase 3 beta , Humanos , Maleimidas/síntese química , Maleimidas/química , Fosforilação/efeitos dos fármacos , Relação Estrutura-Atividade , Proteínas tau/metabolismo
8.
J Clin Transl Hepatol ; 11(7): 1465-1475, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38161505

RESUMO

Background and Aims: Direct evidence on the outcomes of hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) patients with normal alanine transaminase after long-term antiviral treatment is lacking. Methods: HBeAg-negative patients with normal ALT and positive HBV DNA (≥20 IU/mL) were retrospectively enrolled. The endpoints included virological response (HBV DNA<100 IU/mL), changes in aspartate aminotransferase to platelet ratio index (APRI) and fibrosis-4 index (FIB-4), and the incidence of liver nodules, cirrhosis, and hepatocellular carcinoma (HCC). Results: This cohort (n=194) was divided into three subgroups, untreated (n=67), treatment-continued (n=87), and treatment-discontinued patients (n=40), with a median follow-up of 54 months. The treatment-continued group achieved 100% (95% CI: 94.7-100) virological response, and significantly reduced APRI and FIB-4 scores (both p<0.001). The risk of liver nodules and cirrhosis in that group was reduced by 76% (HR: 0.24, 95% CI: 0.11-0.54, p<0.001) and 89% (HR: 0.11, 95% CI: 0.14-0.91, p=0.041) vs. the untreated group and by 77% (HR: 0.23, 95% CI: 0.10-0.49, p<0.001) and 95% (HR: 0.05, 95% CI: 0.01-0.44, p=0.006) vs. the treatment-discontinued group. For patients with HBV DNA≥2,000 IU/mL, adherence to treatment lowered the risks of liver cirrhosis by 92% (95% CI: 0.01-0.67) and 93% (95% CI: 0.01-0.53) vs. the untreated and treatment-discontinued patients, respectively. No patient adhering to treatment developed HCC, but one in each of the remaining groups did. Conclusions: Continuous nucleos(t)ide analog (NA) treatment has a satisfactory effectiveness and helps to lower the risk of liver cirrhosis in HBeAg-negative CHB patients with normal alanine transaminase, especially in those with HBV DNA≥2,000 IU/mL.

9.
Org Biomol Chem ; 10(43): 8720-9, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23037937

RESUMO

Thermal reactions of [60]fullerene with a series of amino acids and amino acid esters under aerobic and dark conditions have been investigated. Fulleropyrrolidines can be obtained from these reactions although an aldehyde is not added purposely. Possible reaction mechanisms involving uncommon C-N bond cleavages have been proposed to generate aldehydes, which then react with amino acids and amino acid esters to provide azomethine ylides, followed by 1,3-dipolar cycloaddition to [60]fullerene affording fulleropyrrolidines. Control experiments support our proposed mechanisms, and elucidate the innate nature of C-N bond cleavages of amino acids and amino acid esters.


Assuntos
Aminoácidos/química , Ésteres/química , Fulerenos/química , Temperatura , Estrutura Molecular
10.
Infect Drug Resist ; 15: 5509-5517, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36158232

RESUMO

Background: Linezolid is classed as oxazolidinone antibiotics which can be used to treat severe infections caused by vancomycin-resistant Enterococcus faecium, hospital-acquired pneumonia caused by Staphylococcus aureus, complicated skin, and uncomplicated skin structure infections (SSSIs) caused by methicillin-susceptible S. aureus or Streptococcus pyogenes, and community-acquired pneumonia caused by Streptococcus pneumoniae. However, many studies have suggested it can also cause thrombocytopenia and pancytopenia. Patients and Methods: We report on three patients with linezolid-pancytopenia. Patients in cases 1 and 2 were diagnosed with heart failure with preserved ejection fraction (HFpEF) and were both administered with dapagliflozin, one of the sodium-dependent glucose transporters 2 inhibitors (SHLT-2i). Results: Two patients were diagnosed with type 2 diabetes, pneumonia, and hyponatremia. Severe myelosuppression occurred in both patients, with a severe decrease in leukocytes and platelets and a moderate decrease in hemoglobin, who eventually passed away despite the discontinuation of linezolid and adopting appropriate treatment measures. The patient in case 3 was diagnosed with pneumonia, type 2 diabetes, and sequelae of cerebral thrombosis. After twelve days of treatment, the patient developed moderate thrombocytopenia and anemia. She recovered without any additional treatment after the discontinuation of linezolid. Conclusion: In this case series, two patients with irreversible myelosuppression were treated with both linezolid and SGLT-2i, and one diabetic patient with single linezolid use presented with reversible pancytopenia, suggesting that SGLT-2i may exacerbate myelosuppression of linezolid. Linezolid should be used with caution in infectious patients with a history of SGLT-2i. We will conduct relevant animal experiments to clarify the interaction between the two drugs.

11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(3): 836-843, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35680814

RESUMO

OBJECTIVE: To analysis the specific protein markers of essential thrombocythemia (ET) based on proteomics technology, to explore and verify the differential protein related to platelet activation. METHODS: Blood samples were obtained from ET patients and healthy people and a certain protein mass spectrometry was detected using label-free quantitative technology. The proteins relative abundance increased or down-regulated by 1.3 times in the disease group compared with the control group, and the protein abundance in the two groups t test P<0.05 were defined as differential proteins. Bioinformatics analysis of the differential proteins was performed using GO and KEGG. The difference in the average protein abundance between the two groups was analyzed by t test and P<0.05 was considered statistically significant. Differential proteins were selected for verification by parallel reaction monitoring (PRM) technology. RESULTS: A total of 140 differential proteins were found, of which 72 were up-regulated and 68 were down-regulated. KEGG enrichment showed that the differential protein expression was related to the platelet activation pathway. The differential proteins related to platelet activation were GPV, COL1A2, GP1bα, COL1A1 and GPVI. Among them, the expressions of GPV, GP1bα and GPVI were up-regulated, and the expressions of COL1A2 and COL1A1 were down-regulated. PRM verification of COL1A1, GP1bα, GPVI and GPV was consistent with LFP proteomics testing. CONCLUSION: Differential proteins in ET patients are related to platelet activation pathway activation.Differential proteins such as GPV, GPVI, COL1A1 and GP1bα can be used as new targets related to ET platelet activation.


Assuntos
Trombocitemia Essencial , Plaquetas/metabolismo , Humanos , Ativação Plaquetária , Glicoproteínas da Membrana de Plaquetas/metabolismo , Tecnologia
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(2): 522-528, 2022 Apr.
Artigo em Zh | MEDLINE | ID: mdl-35395990

RESUMO

AbstractObjective: To analyze the DNA methylation gene mutations of myeloproliferative neoplasm (MPN), and preliminarily explore its clinical features. METHODS: Next-generation sequencing technology was used to detect 31 MPN-related genes in 105 cases of MPN patients ï¼»40 cases of polycythaemia vera (PV), 65 cases of essential thrombocythemia (ET)ï¼½, and to analyze the relationship between DNA methylation gene mutations and clinical features. RESULTS: 15 mutation types were detected in 105 patients (88 mutations in total), and the total mutation detection rate was 87.6% (92/105). A total of 23 mutations in 4 DNA methylation genes (TET2, DNMT3A, IDH1, IDH2) were detected in 22 patients. The mutation rate of DNA methylation genes was 21.0%, mainly in the form of double mutations, including JAK2 V617F and TET2 (n=10), JAK2 V617F and DNMT3A (n=4), CALR and TET2 (n=2), JAK2 V617F and IDH1 (n=1). Compared with MPN patients without DNA methylation gene mutations, the proportion of women with DNA methylation gene mutations and the white blood cell count (WBC) were significantly higher (P<0.05). Compared with MPN patients with triple-negative driver genes, the proportion of women with DNA methylation gene mutations, age, WBC, platelet count (PLT), and neutrophil-to-lymphocyte ratio (NLR) were significantly higher (P<0.05). The remaining difference was not statistically significant (P>0.05). The MPN10 score, the incidence of thrombotic events, and the proportion of medium-risk and high-risk patients with DNA methylation gene mutations were significantly higher than those of MPN patients without DNA methylation gene mutations (P<0.05). CONCLUSION: The mutation rate of DNA methylation genes was 21.0%, mainly coexisting in the form of double mutations. The proportion of women with DNA methylation gene mutations in MPN patients and WBC is high, the symptom load is heavy, the incidence of thrombosis is high, and the proportion of medium-high-risk patients is high, suggesting that their prognosis may be poor.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Calreticulina/genética , Metilação de DNA , Feminino , Humanos , Janus Quinase 2/genética , Mutação , Transtornos Mieloproliferativos/genética , Policitemia Vera/genética
13.
J Thorac Dis ; 14(10): 4031-4043, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36389300

RESUMO

Background: Thoracoscopic-assisted Nuss repair is a commonly used method for treating pectus excavatum, which has always been performed under tracheal intubation and general anesthesia. However, general anesthesia with endotracheal intubation can produce intubation and anesthetic drug related complications. In non-intubation anesthesia, laryngeal mask is used instead of tracheal intubation without muscle relaxants and small doses of sedative and analgesic drugs. Therefore, non-intubation anesthesia can reduce complications and speed up postoperative recovery. This study retrospectively analyzed the clinical impact of these two anesthesia methods on thoracoscopic-assisted Nuss repair for the treatment of pectus excavatum. Methods: A total of 115 pectus excavatum patients who underwent thoracoscopic-assisted Nuss procedure repair in the Department of Thoracic Surgery of Yunnan First People's Hospital from January 2017 to January 2022 were included. All subjects in this study underwent thoracoscopic assisted Nuss repair in the same thoracic surgical team. According to different anesthesia methods, they were divided into non-intubation anesthesia group (n=62) and intubation anesthesia group (n=53). The intubation time, intraoperative mean heart rate, postoperative complications, postoperative first oral food intake, water intake, ambulation, defecation time, postoperative blood drawing results, postoperative hospital stay and total hospitalization cost were compared between the two groups. Results: There were no significant differences in clinical characteristics and preoperative examination indexes between the two groups, which were comparable. Compared with the intubation anesthesia group, the non-intubation anesthesia group had less anesthesia intubation time, lower intraoperative mean heart rate, less postoperative complications, such as pneumothorax, pleural effusion, and lung infection. In the non-intubation anesthesia group, the first time to eat, drink, get out of bed, and defecate were all earlier. Routine blood results 24 h after surgery indicated that the non-intubation anesthesia group had lower white blood cell, neutrophil and lymphocyte, an earlier postoperative discharge time, and lower total hospitalization expenses. Conclusions: Non-intubation anesthesia in thoracoscopic-assisted Nuss procedure for the repair of pectus excavatum can make the postoperative recovery of patients faster and has better safety and efficacy.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(4): 1115-8, 2011 Apr.
Artigo em Zh | MEDLINE | ID: mdl-21714272

RESUMO

Copper and lead in soil samples were measured by using inductively coupled plasma mass spectrometry(ICP-MS), and the impacts of major source of measurement uncertainty were discussed. Uncertainty components such as sample weighing in the process of digestion, the volume size, preparation of standard solutions, curve fitting, measurement repeatability were analyzed and synthesized according to JJF1059-1999 (Evaluation and Expression of Uncertainty in Measurement), and the final expanded uncertainty was given. Such expression of result was more objective and true.

15.
Am J Transl Res ; 13(10): 11548-11555, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34786081

RESUMO

BACKGROUND: Breast carcinoma (BC) is a commonly seen malignancy in women. Although traditional radical mastectomy can improve the survival of patients, it can cause breast loss and chest wall deformities, which seriously affects the daily life of patients and causes anxiety and depression. The purpose of this research project is to investigate the effect of breast reconstruction with latissimus dorsi myocutaneous flap (LDMF) after nipple- and areola-sparing modified radical mastectomy (MRM) on the psychological mood and quality of life (QoL) of patients with stage I BC. METHODS: A total of 102 patients with BC (research group, RG) treated in the Shanghai Fifth People's Hospital, Fudan University from January 2018 to December 2020 were selected for phase I breast reconstruction with LDMF after nipple- and areola-sparing MRM. Concurrently, 50 BC patients (control group, CG) who underwent traditional total mastectomy in our hospital were collected. The activities of daily living (ADL), self-rating anxiety scale (SAS) and self-rating depression scale (SDS) scores were observed before and 1 month after treatment. The intraoperative indicators, postoperative complications, postoperative satisfaction rate and overall survival rate were compared. RESULTS: The Functional Assessment of Cancer Therapy-Breast Cancer (FACT-B) score was higher after treatment, while SAS and SDS scores were lower in RG than in CG (P<0.05). No statistical difference was observed in intraoperative blood loss, wound drainage time, operation time, postoperative complications and overall survival rate between the two cohorts (P>0.05). RG showed higher satisfaction degree and overall satisfaction rate, as well as better QoL than CG (P<0.05). CONCLUSIONS: Breast reconstruction with LDMF after nipple- and areola-sparing MRM can alleviate adverse emotions of patients with stage I BC and improve their QoL.

16.
Materials (Basel) ; 14(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34639918

RESUMO

The failure mechanisms of Cu-Cu bumps under thermal cycling test (TCT) were investigated. The resistance change of Cu-Cu bumps in chip corners was less than 20% after 1000 thermal cycles. Many cracks were found at the center of the bonding interface, assumed to be a result of weak grain boundaries. Finite element analysis (FEA) was performed to simulate the stress distribution under thermal cycling. The results show that the maximum stress was located close to the Cu redistribution lines (RDLs). With the TiW adhesion layer between the Cu-Cu bumps and RDLs, the bonding strength was strong enough to sustain the thermal stress. Additionally, the middle of the Cu-Cu bumps was subjected to tension. Some triple junctions with zig-zag grain boundaries after TCT were observed. From the pre-existing tiny voids at the bonding interface, cracks might initiate and propagate along the weak bonding interface. In order to avoid such failures, a postannealing bonding process was adopted to completely eliminate the bonding interface of Cu-Cu bumps. This study delivers a deep understanding of the thermal cycling reliability of Cu-Cu hybrid joints.

17.
Materials (Basel) ; 14(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771919

RESUMO

In microelectronic packaging technology for three-dimensional integrated circuits (3D ICs), Cu-to-Cu direct bonding appears to be the solution to solve the problems of Joule heating and electromigration (EM) in solder microbumps under 10 µm in diameter. However, EM will occur in Cu-Cu bumps when the current density is over 106 A/cm2. The surface, grain boundary, and the interface between the Cu and TiW adhesion layer are the three major diffusion paths in EM tests, and which one may lead to early failure is of interest. This study showed that bonding strength affects the outcome. First, if the bonding strength is not strong enough to sustain the thermal mismatch of materials during EM tests, the bonding interface will fracture and lead to an open circuit of early failure. Second, if the bonding strength can sustain the bonding structure, voids will form at the passivation contact area between the Cu-Cu bump and redistribution layer (RDL) due to current crowding. When the void grows along the passivation interface and separates the Cu-Cu bump and RDL, an open circuit can occur, especially when the current density and temperature are severe. Third, under excellent bonding, when the voids at the contact area between the Cu-Cu bump and RDL do not merge together, the EM lifetime can be more than 5000 h.

18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1533-1539, 2021 Oct.
Artigo em Zh | MEDLINE | ID: mdl-34627436

RESUMO

OBJECTIVE: To investigate the relationship between JAK2 gene mutation and clinical indicators in patients with myeloproliferative neoplasms (MPN). METHODS: 122 MPN patients in the Department of Hematology, Xiyuan Hospital, China Academy of Chinese Medical Sciences from September 2017 to January 2020 were retrospectively analyzed. The relationship between JAK2 gene mutation and sex, age, peripheral blood cell count, splenomegaly, and thrombosis and bleeding events were analyzed. RESULTS: In 122 patients with MPN, the patients with polycythemia vera (PV) accounted for 36 (29.5%), the patients with essential thrombocythemia (ET) accounted for 56 (45.9%), the patients with myelofibrosis (MF) accounted for 30 (24.6%). The JAK2 gene mutation rate in MPN patients was 64.6% (79/122), and the JAK2 gene mutation rate in PV, ET and MF groups were 77.7% (28/36), 60.7% (34/56) and 56.7% (17/30), the JAK2 gene mutation rate of the patients in PV group was statistically significant as compared with those in the ET group (P<0.05). The hemoglobin (Hb) count of the patients in JAK2 gene mutation group was higher than those in wild-type group ï¼»(150.0±39.6)g/L vs (129.4±38.9)g/L, P<0.05ï¼½; the white blood cell (WBC) count of the patients in JAK2 gene mutation group was higher than those in the wild type group ï¼»(9.5±4.7)×109/L vs (8.4±46.9)×109/L, P<0.05ï¼½. As for the patients in PV group, the platelet count of the patients in JAK2 gene mutation group was higher than those in the wild type group ï¼»(370.2±113.1)×109/L vs (264.8±63.9)×109/L, P<0.05ï¼½. The incidence of splenomegaly in MPN patients was 35.2% (43/122), and the incidence of splenomegaly in MF patients was 63.3% (19/30), and the incidence of splenomegaly in the patients in JAK2 gene mutation group in MF group (82.4%, 12/17) was significantly higher than those in the wild-type group (38.5%, 5/13) (P<0.05). CONCLUSION: The mutation rate of JAK2 gene in MPN patients is higher, and the mutation rate of JAK2 gene in PV patients is higher than that in ET and MF patients; JAK2 gene mutations in MPN patients are related to hemogram index; the incidence of splenomegaly is the highest in MF patients, and splenomegaly is related to the occurrence of JAK2 gene mutations in MF patients.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Humanos , Janus Quinase 2/genética , Taxa de Mutação , Transtornos Mieloproliferativos/genética , Estudos Retrospectivos
19.
Ann Transl Med ; 9(12): 970, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34277770

RESUMO

BACKGROUND: The merits of spontaneous ventilation video-assisted thoracic surgery (SV-VATS) are still controversial. Our team retrospectively evaluated the intraoperative and postoperative advantages of this surgical approach, comparing with mechanical ventilation video-assisted thoracic surgery (MV-VATS). METHODS: We did a single center retrospective study at the First Affiliated Hospital of Yunnan Province. 244 patients were eventually assigned to the SV-group and MV-group, and their intraoperative indicators and thoracic surgery postoperative data were included in the comparison. RESULTS: The SV-group exhibited markedly less intraoperative bleeding and postoperative thoracic drainage, and the bleeding volume was correlated with the volume and duration of drainage. Further analysis showed that, patients undergoing SV-VATS had less activation of white blood cells and neutrophils after surgery, but they also had lower serum albumin concentrations. Risks of short-term postoperative complications, including inflammatory reactions, malignant arrhythmias, constipation, and moderate or more pleural effusions, were also significantly reduced in the SV-group. Additionally, hospitalization cost was lower in the SV-group than that in the MV-group. CONCLUSIONS: SV-VATS is suitable for various types of thoracic surgery, and effectively reduce intraoperative bleeding and postoperative thoracic drainage. With less postoperative inflammatory response, it reduces the risk of short-term postoperative complications. It is also able to help to reduce the financial burden of patients.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(11): 2897-901, 2010 Nov.
Artigo em Zh | MEDLINE | ID: mdl-21284148

RESUMO

Differential optical absorption spectroscopy (DOAS) technique has been used to measure trace gases in the atmosphere by their strongly structured absorption of radiation in the UV and visible spectral range, and nowadays this technique has been widely utilized to measure trace polluted gases in the atmosphere e.g. SO2, NO2, O3, HCHO, etc. However, there exists lamp (xenon lamp or deuteriumlamp) spectrum structure in the measured band (300-700 nm) of the absorption spectra of atmosphere, which badly impacts on precision of retrieving the concentration of trace gases in the atmosphere. People home and abroad generally employ two ways to handle this problem, one is segmenting band retrieving method, another is remedial retrieving method. In the present paper, a new retrieving method to deal with this trouble is introduced. The authors used moving-window average smoothing method to obtain the slow part of the absorption spectra of atmosphere, then achieved the lamp (xenon lamp in the paper) spectrum structure in the measured band of the absorption spectra of atmosphere. The authors analyzed and retrieved the measured spectrum of the atmosphere, and the result is better than the forenamed ways. Chi-square of residuum is 2.995 x 10(-4), and this method was proved to be able to avoid shortcoming of choosing narrowband and disadvantage of discovering the new component of atmosphere in retrieving the concentration of air pollutants and measuring the air pollutants.

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