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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 58(12): 1281-1290, 2023 Dec 09.
Article in Chinese | MEDLINE | ID: mdl-38061871

ABSTRACT

Objective: To systematically assess the durability of the 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) pretreated resin-to-zirconia bonding and conducted a meta-analysis to provide clinical guidance on zirconia bonding strategies. Methods: A comprehensive search was conducted on PubMed, Scopus, Web of Science, CNKI, and Wanfang database to identify relevant studies on the resin-to-zirconia bonding after surface pretreatment with 10-MDP. Strict inclusion and exclusion criteria were applied to select appropriate literature and extract essential information and data. The included studies were categorized based on aging methods (water storage, thermocycling, or both), 10-MDP application methods (within primer, adhesive, resin cement, or both), and additional surface treatments (alumina sandblasting, tribochemical silica coating, acid etching, laser etching, and plasma treatment) and were analyzed by Review Manager 5.4. The evaluation indicator was the bonding strength of zirconia after surface pretreatment with 10-MDP. Results: A total of 72 studies were included in the systematic review, with 68 studies eligible for the meta-analysis. The bonding strength of zirconia decreased significantly after aging [P<0.001; mean difference (MD): 5.58; 95%CI: 5.11-6.05]. No significant differences in bonding strength of zirconia were observed after aging when employing various application methods of 10-MDP (all P>0.05). The bonding strength of zirconia was significantly enhanced after aging when 10-MDP was applied in conjunction with additional surface treatments, as compared to the application of 10-MDP alone (P<0.001; MD: 10.17; 95%CI: 8.20-12.14). Conclusions: The bonding strength of zirconia pretreated with 10-MDP exhibited a reduction after undergoing water storage or thermocycling. The application of 10-MDP with additional surface treatments enhanced the bonding strength of zirconia after aging, while the application methods of 10-MDP did not exert an influence.


Subject(s)
Dental Bonding , Shear Strength , Surface Properties , Methacrylates , Resin Cements , Zirconium , Water , Materials Testing
2.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(5): 516-522, 2022 May 09.
Article in Chinese | MEDLINE | ID: mdl-35484675

ABSTRACT

Objective: To evaluate the effects of pre-sintering heating rate and powder size on dental recycled zirconia. Methods: Recycled zirconia powders were sieved to obtain the large (50 µm0.05). When the pre-sintering heating rates were 2 ℃/min, 5 ℃/min, and 8 ℃/min, the flexural strengths of the large-particle recycled zirconia were (421.2±54.7), (444.2±70.1) and (427.5±68.4) MPa, the flexural strengths of the small-particle recycled zirconia were (750.1±74.1), (777.2±95.5) and (746.7±73.0) MPa, respectively. The flexural strength of commercial zirconia was (988.4±129.8) MPa. The flexural strengths of the recycled zirconia were significantly lower than that of the commercial zirconia (P<0.05). At the same pre-sintering heating rate, the flexural strengths of the small-particle recycled zirconia were significantly higher than that of the large-particle recycled zirconia (P<0.05). Conclusions: Compared with the large particles, small-particle recycled zirconia powders can effectively improve the properties of recycled zirconia, while the pre-sintering heating rate has no effect on the properties of the recycled zirconia.


Subject(s)
Ceramics , Dental Materials , Dental Materials/chemistry , Heating , Materials Testing , Powders , Surface Properties , Yttrium , Zirconium
3.
Data Brief ; 30: 105524, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32322637

ABSTRACT

Two types of cements were selected as the reference cement in the priority program 2005 of the German Research Foundation (DFG SPP 2005). A thorough characterization of CEM I 42.5 R has been made in a recent publication [1]. In this paper, the characterization data of the other reference cement CEM III/A 42.5 N are presented from the aspects of chemical and mineralogical compositions as well as physical and chemical properties. The characterization data of the slag, which is the second main constituent of this specific cement besides the clinker, are presented independently. For all data received, the mean values and the corresponding errors were calculated. The data shall be used for the ongoing research within the priority program. Also, researchers from outside this priority program can benefit from these data if the same materials are used.

4.
Zhonghua Yi Xue Za Zhi ; 100(9): 710-712, 2020 Mar 10.
Article in Chinese | MEDLINE | ID: mdl-32187917

ABSTRACT

Reports a case of diabetic foot patient with right toe pain, ulceration for 4 years and aggravation for 1 month. After rigorous medical treatment and related examinations, transeversal bone transfer of tibia was proposed. However, the skin condition on the inner side of the lower leg was not good before the operation, so the transversal bone removal of the fibula was performed. Two segments of the lateral fibula were osteotomized with miniature osteotomies. The two osteotomy lines were about 10 cm apart. The distal osteotomy line is about 10 cm from the tip of the lateral malleolus. On the 8th day after the surgery, the bone was moved every 6 hours and was extended inwards by 1 mm every day. After 14 days, the bone was moved back for another 14 days. Skin temperature from preoperative to postoperative, ankle brachial index, CT angiography, CT value, visual analogue scale (VAS) of pain and wound healing were evaluated by comparison. The wound was completely healed 28 days after the operation.


Subject(s)
Diabetic Foot , Tarsal Bones , Diabetic Foot/surgery , Fibula , Humans , Osteotomy , Tibia
5.
Data Brief ; 27: 104699, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31720343

ABSTRACT

A thorough characterization of starting materials is the precondition for further research, especially for cement, which contains various phases and presents quite a complex material for fundamental scientific investigation. In the paper at hand, the characterization data of the reference cement CEM I 42.5 R used within the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented from the aspects of chemical and mineralogical compositions as well as physical and chemical properties. The data were collected based on tests conducted by nine research groups involved in this cooperative program. For all data received, the mean values and the corresponding errors were calculated. The results shall be used for the ongoing research within the priority program.

6.
Insect Mol Biol ; 27(1): 123-132, 2018 02.
Article in English | MEDLINE | ID: mdl-29030999

ABSTRACT

The Bemisia tabaci Mediterranean (MED) cryptic species is an invasive pest, distributed worldwide, with high ecological adaptability and thermotolerance. DNA methylation (a reversible chromatin modification) is one possible change that may occur within an organism subjected to environmental stress. To assess the effects of temperature stress on DNA methyltransferase 3 (Dnmt3) in MED, we cloned and sequenced BtDnmt3 and identified its functions in response to high and low temperatures. The full-length cDNA of BtDnmt3 was 3913 bp, with an open reading frame of 1962 bp, encoding a 73.89 kDa protein. In situ hybridization showed that BtDnmt3 was expressed mainly in the posterior region. BtDnmt3 messenger RNA expression levels were significantly down-regulated after exposure to heat shock and significantly up-regulated after exposure to cold shock. Furthermore, after feeding on double-stranded RNA specific for BtDnmt3, both heat resistance and cold resistance were significantly decreased, suggesting that BtDnmt3 is associated with thermal stress response and indicating a differential response to high- and low-temperature stress in MED. Together, these results highlight a potential role for DNA methylation in thermal resistance, which is a process important to successful invasion and colonization of an alien species in various environments.


Subject(s)
DNA Modification Methylases/genetics , Heat-Shock Response/genetics , Hemiptera/physiology , Insect Proteins/genetics , Amino Acid Sequence , Animals , Cold Temperature , DNA Modification Methylases/metabolism , Female , Hemiptera/genetics , Hot Temperature , Insect Proteins/metabolism , Male , Phylogeny , Sequence Alignment
7.
Genet Mol Res ; 14(1): 2055-62, 2015 Mar 20.
Article in English | MEDLINE | ID: mdl-25867351

ABSTRACT

The major histocompatibility complex (MHC) is one of the most important genetic systems associated with resistance to infectious diseases in vertebrates. The spotted seal (Phoca largha) is one of the most endangered species in China. In this study, we present the first step in the molecular characterization of a DRB-like locus in the spotted seal by analyzing the nucleotide sequence of the polymorphic exon 2 segments, a 288-nucleotide sequence. By examining the segment from a group of 41 individuals, 28 alleles were identified. No deletion, insertion, or exceptional stop codon was detected, suggesting that these alleles could be functional in vivo. The nucleotide and amino acid sequences of the segment both showed a relatively high level of similarity (nucleotides 97%; amino acids 98%) to those of Meles meles and Zalophus californianus. The high level of spotted seal MHC-DRB polymorphism revealed in the present study has not been reported for the Phocidae and could be a consequence of the small spotted seal population adapting to the Bohai Sea, which probably has a relatively high level of pathogens.


Subject(s)
Major Histocompatibility Complex/genetics , Phoca/genetics , Alleles , Amino Acids/genetics , Amino Acids/metabolism , Animals , China , Exons , Gene Duplication , Genetic Variation , High-Throughput Nucleotide Sequencing , Phoca/classification , Phylogeny , Polymorphism, Genetic
8.
Neotrop Entomol ; 43(4): 362-72, 2014 Aug.
Article in English | MEDLINE | ID: mdl-27193815

ABSTRACT

Bactrocera (Tetradacus) minax Enderlein is a major pest to wild and cultivated species of citrus. Bactrocera minax produces one generation per year with a long pupal diapause period of over 6 months, which hinders efforts to obtain vast numbers of insects under standard room conditions. Determining the mechanisms of diapause is significantly important for obtaining large quantities of these insects. To characterize the heat shock protein (Hsp) genes of B. minax and to unravel their potential contribution to diapause, we performed 3' and 5' RACE to isolate the complementary DNA (cDNA) sequences, bioinformatics to examine the phylogenetic relationships, and real-time quantitative PCR to detect the expression patterns of three Hsp genes during various developmental stages. These results represent the first characterization of the three Hsp genes of B. minax; the open reading frames of Bmhsp23, Bmhsp70, and Bmhsp90 were 510, 1,911, and 1,089 bp, encoding 170, 636, and 363 amino acids, respectively. BmHsp70 and BmHsp90 displayed high identity to previously identified Hsp70 and Hsp90 genes, respectively. BmHsp23 displayed varying similarity, from 28 to 83%, to previously identified small Hsps. Bmhsp23 messenger RNA (mRNA) expression was found to be upregulated during diapause initiation, maintenance, and termination. Bmhsp70 mRNA expression peaked during diapause initiation. Bmhsp90 mRNA expression remained at a relatively low level during deep diapause. Our present results suggest that Bmhsp70 might play an important role in diapause initiation, while Bmhsp23 in diapause initiation and maintenance and Bmhsp90 in diapause regulation. These results improve our understanding of the mechanism of diapause in B. minax at the molecular level.


Subject(s)
Diapause, Insect , Heat-Shock Proteins/genetics , Tephritidae/genetics , Animals , Cloning, Molecular , Phylogeny , Tephritidae/physiology
9.
Neotrop Entomol ; 42(5): 521-6, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23949985

ABSTRACT

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East-Asia Minor 1 (MEAM1) is invasive and adaptive to varied environments throughout the world. The adaptability is closely related to genomic variation such as single nucleotide polymorphisms (SNPs) and insertions/deletions (indels). In order to elucidate the feature of SNPs and indels in MEAM1, and reveal the association between SNPs/indels and adaptive capacity to various environments, a computational approach with QualitySNP was used to identify reliable SNPs and indels on the basis of 9110-expressed sequence tags of MEAM1 present in the NCBI database. There were 575 SNPs detected with a density of 10.1 SNPs/kb and 6.4 SNPs/contig. Also, 237 transitions (39.3%) and 366 transversions (60.7%) were obtained, where the ratio of transitions to transversions was 0.65:1. In addition, 581 indels with a density of 14.1 indels/kb and 9.2 indels/contig were detected. Collectively, it showed that invasive MEAM1 has high SNPs density, and higher SNPs percentage than non-invasive B. tabaci species. A high SNPs density/percentage in MEAM1 yielded a high genomic variation that might have allowed it to adapt to varied environments, which provides some support to understand the invasive nature of MEAM1 at the genomic level. High levels of genomic variation are implicated in the level of adaptive capacity and invasive species are thought to exhibit higher levels of adaptive capacity than non-invasive species.


Subject(s)
Hemiptera/genetics , Introduced Species , Polymorphism, Single Nucleotide , Adaptation, Physiological , Animals , Middle East
10.
J Fish Biol ; 77(5): 1071-82, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21039491

ABSTRACT

To investigate the genetic diversity and describe the population structure in Gadus macrocephalus, a 452 base pair (bp) fragment of the mitochondrial DNA control region was analysed in 259 individuals. The results showed remarkably low nucleotide diversity and a lack of genealogical structure. Small but significant genetic differentiations, however, were detected among north-western Pacific populations, but no large-scale regional differences were detected. These results indicate that populations of G. macrocephalus in the north-western Pacific are genetically subdivided and represent evolutionary lineages that should be managed individually.


Subject(s)
DNA, Mitochondrial/genetics , Gadiformes/genetics , Genetic Variation , Genetics, Population , Animals , Haplotypes , Sequence Analysis, DNA
11.
J Int Med Res ; 37(4): 975-82, 2009.
Article in English | MEDLINE | ID: mdl-19761679

ABSTRACT

Psychotherapy, including cognitive behavioural therapy (CBT), reminiscence and general psychotherapy (GPT), is viewed as effective treatment for depression, but its efficacy in older people is not well defined. This systematic review included 14 randomized controlled trials that assessed the efficacy of psychotherapy for treating depression in elderly people (> or = 55 years). The results of this meta-analysis showed that, compared with placebo, psychotherapy was more effective in reducing depression scores (standardized mean difference -0.92; 95% confidence interval -1.21, -0.36). Subgroup analysis showed that CBT, reminiscence and GPT were all more effective than placebo; psychotherapy as an adjunct to antidepressant medication did not increase effectiveness. There was no significant difference between CBT and reminiscence in improving depression. A higher drop-out rate was observed in studies that did not include psychotherapy versus those that did, although this difference was not statistically significant. Thus, various general formats of psychotherapy are effective for treating depression in older people, although psychotherapy does not significantly increase the effectiveness of anti-depressant medication.


Subject(s)
Aged/psychology , Cognitive Behavioral Therapy , Depression/therapy , Memory , Female , Humans , Male , Middle Aged , Randomized Controlled Trials as Topic , Treatment Outcome
12.
Zhonghua Zhong Liu Za Zhi ; 16(6): 451-3, 1994 Nov.
Article in Chinese | MEDLINE | ID: mdl-7720504

ABSTRACT

Anastomotic stricture has become a common complication following surgical treatment of upper gastrointestinal cancers. A technique was devised to alleviate the stricture with Nd. YAG laser beam under endoscopy. The laser beam was applied at 3-4 different points near the anastomotic stoma. The thermal effect of the beam would cut the scar tissues in and underneath the mucosa, leading to dilatation of the stoma. A total of 48 patients with cancer of the esophagus (n = 21), gastric cardia (n = 20), body of stomach (n = 6) and gastric stump (n = 1) with postoperative anastomotic stricture was so treated. According to the degree of dilatation, the result of treatment upon longterm follow-up was good (the anastomotic stoma was enlarged more than 6 mm) in 41 (85.4%), fair (the stoma enlarged 4-5 mm) in 5 (10.4%) and poor in the remaining 2. Due precautions should be made to avoid bleeding and perforation.


Subject(s)
Esophageal Stenosis/surgery , Laser Therapy/methods , Adult , Aged , Anastomosis, Surgical/adverse effects , Cardia , Dilatation , Esophageal Neoplasms/surgery , Esophagoscopy , Female , Humans , Male , Middle Aged , Stomach Neoplasms/surgery
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