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The individualized precision management of hereditary pheochromocytoma (PHEO) and paraganglioma (PGL) syndromes (PPGLs) based on molecular diagnosis and molecular subtype is becoming more popular. The newly discovered MAX germline mutation-associated PPGLs are autosomally dominant and rare. To raise awareness and explore the effective management of individual diagnosis and treatment, the relevant literature published between January 2011 and February was systematically reviewed. There were a total of 101 patients in the 77 families, involving all 5 exons, containing 44 types of MAX germline mutations and mostly concentrated in exons 3 and 4 (64.4%), the main mutations were nonsense mutations and missense mutations (72.3%), and some were large fragment deletions or insertions, intron variant, gene fusion mutations were relatively infrequent. Furthermore, about 10% of the patients had a paternal parent-of-origin effect. Among the 101 patients, 96 (95.0%) developed PHEO including 15 metastatic PHEO, 61 bilateral PHEO and 35 unilateral PHEO. The age of diagnosis was (31.7±10.9) years (range: 13 to 80 years). The male to female ratio was 1.2â¶1. Eleven were accompanied with chest and abdominal PGL. Eight (7.9%) were accompanied by functional pituitary adenoma. And 12 (11.9%) developed other neuroendocrine tumors (NET), of which 8 were accompanied by PHEO, including 4 hyperparathyroidism, 1 gangliocytoma and neuroblastoma, 1 pancreatic NET, 1 medullary thyroid carcinoma and 1 C cell hyperplasia. Six presented concomitant non-NET, including 1 tongue squamous cell carcinoma, 1 papillary thyroid carcinoma, 1 prostate cancer, 1 renal oncocytoma, 1 breast cancer with renal oncocytoma, and 1 thoracic chondrosarcoma with multifocal adenocarcinoma of lung. The remaining 5 cases (5.0%), including 4 other NET (2 ganglioblastoma, 1 abdominal neuroblastoma and 1 pancreatic NET) and 1 asymptomatic child, did not present PHEO. The MAX germline mutation may cause a novel multiple endocrine neoplasia, which can be described as type 5. A comprehensive baseline assessment of neural crest cell-derived diseases such as PPGL, pituitary adenoma, hyperparathyroidism, and/or gangliocytoma (neuroblastoma) was recommended for all people with MAX germline mutations, and the risk of bilateral and/or metastatic PHEO should also be considered. In contrast, patients with PPGLs combined with other NET, such as functional pituitary adenoma, should undergo genetic testing and pedigree screening that includes at least the MAX gene.
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Neoplasias das Glândulas Suprarrenais , Mutação em Linhagem Germinativa , Paraganglioma , Feocromocitoma , Humanos , Feocromocitoma/genética , Paraganglioma/genética , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/diagnóstico , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Masculino , FemininoRESUMO
Objective: To study the correlation between patients with type 2 diabetes mellitus combined with nonalcoholic steatohepatitis in order to provide theoretical support for the treatment of NAFLD through aerobic exercise performance. Methods: 253 cases with T2DM combined with NAFLD were selected. 93 cases consented to undergo a liver biopsy. Among them, 74 cases with liver biopsy successfully passed the symptom-limited cardiopulmonary exercise test (CPET) and respiratory quotient (RQ)≥1.05. Patients were divided into two groups according to the NAFLD activity score (NAS) of the pathological biopsy: the non-NASH group (NAS < 4) and the NASH group (NAS≥4). The differences in general clinical and biochemical indicators and exercise parameters were compared between the two groups. The relevant factors that affect aerobic exercise performance in NAFLD patients were explored by correlation and regression analysis. Results: The peak oxygen uptake [VO2 @ peak, (17.82 ± 5.61) ml·kg(-1)·min(-1) and (23.14 ± 5.86) ml·kg(-1)·min(-1)] and anaerobic threshold [VO2 @ AT, (11.47 ± 3.12) ml·kg(-1)·min(-1) and (13.81 ± 3.53) ml·kg(-1)·min(-1)] were lower in the NASH group than those in the non-NASH group in T2DM patients, with P < 0.01, indicating a significant decrease in aerobic exercise performance in NASH patients compared to non-NASH patients. Correlation analysis showed that patients with T2DM combined with NAFLD VO2@peak was positively correlated with RQ, carbohydrate oxidation rate (%CHO), daily carbohydrate energy supply (CHO Kcal/d), high-density lipoprotein cholesterol (HDL-C), and maximal voluntary ventilation (MVV) (r 0.360, 0.334, 0.341, 0.255, 0.294, P < 0.05 or P < 0.01, respectively) and negatively correlated with NAS score, fat attenuation, liver stiffness, fat oxidation rate (%FAT), daily fat energy supply (FAT Kcal/d), aspartate aminotransferase (AST), alanine aminotransferase (ALT), body mass, and body mass index (BMI) (r -0.558, -0.411, -0.437, -0.340, -0.270, -0.288, -0.331, -0.295, -0.469, P < 0.05 or P < 0.01, respectively). VO2@AT were positively correlated with RQ, %CHO, total cholesterol (TC), and HDL-C (r 0.351, 0.247, 0.303, 0.380, P < 0.05 or P < 0.01, respectively), while it was negatively correlated with NAS score, fat attenuation, liver stiffness, %FAT, FAT (Kcal/d), ferritin (Fer), ALT, AST, body weight, and BMI (r -0.330, -0.384, -0.428, -0.270, -0.318, 0.320, -0.404, -0.416, -0.389, -0.520, P < 0.05 or P < 0.01, respectively). Stepwise multiple regression analyses revealed that BMI, RQ, and NAS scores were independent correlated factors of aerobic exercise performance. Conclusion: Hepatic inflammation and fibrosis affect the aerobic exercise performance of patients with T2DM combined with NAFLD.
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Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Diabetes Mellitus Tipo 2/complicações , Colesterol , Exercício Físico , Carboidratos , Fígado/patologiaRESUMO
The article "MiR-195-5p inhibits the cell migration and invasion of cervical carcinoma through suppressing ARL2", by S.-S. Pan, H.-E. Zhou, H.-Y. Yu, L.-H. Xu, published in Eur Rev Med Pharmacol Sci 2019; 23 (24): 10664-10671-DOI: 10.26355/eurrev_201912_19764-PMID: 31858533 has been retracted by the Authors for the following reasons: The authors found some inaccuracies in the research due to the number of experiments, as well as problems in the editing process of pictures. These errors may mislead readers and affect scientific research in this field. Figures 2D and 5D have also been questioned on PubPeer in April 2023. https://www.europeanreview.org/article/19764 This manuscript has been withdrawn. The Publisher apologizes for any inconvenience this may cause.
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Objective: To investigate the expression level and clinical significance of cSMARCA5 in the patients with acute myocardial infarction (AMI). Methods: This study was a case-control study. A total of 100 patients with AMI and 100 patients without coronary heart disease who received treatment in the Department of Cardiology, Peking University Third Hospital from September to December 2021 were included in the study according to the principle of 1â¶1 frequency matching. The expression levels of cSMARCA5 in the peripheral blood of AMI patients and control groups were measured by real-time quantitative polymerase chain reaction (RT-qPCR). The receiver operating characteristic (ROC) curve was used to calculate the diagnostic ability of cSMARCA5 for AMI. Spearman or Pearson correlation analysis was used to explore the correlation between cSMARCA5 and the degree of myocardial necrosis, coronary lesion severity and GRACE risk stratification score. Bioinformatics analysis was used to predict the possible mechanism of cSMARCA5 in pathological changes of AMI. Results: The age [M (Q1,Q3)] of AMI patients and control group was 63.0 (56.0, 71.5) and 63.0 (53.0, 75.5) (P=0.622), and the proportion of males was 75.0% (75 cases) and 46.0% (46 cases) (P<0.001), respectively. The expression level [M (Q1,Q3)] of cSMARCA5 was significantly lower in AMI patients compared with the control group [0.37 (0.22, 0.73) vs 1.03(0.71, 1.75), P<0.001]. ROC analysis showed that the area under the curve of cSMARCA5 in diagnosing AMI was 0.83 (95%CI: 0.77-0.89, P<0.001), with a sensitivity of 89.0% and specificity of 67.7%. cSMARCA5 was negatively correlated with creatine kinase isoenzyme MB (r=-0.203, P=0.041), troponin T (r=-0.230, P=0.023) and N-terminal brain natriuretic peptide precursor (r=-0.250, P=0.012), and positively correlated with left ventricular ejection fraction (r=0.201, P=0.042). In addition, the expression level of cSMARCA5 was negatively correlated with SYNTAX score (r=-0.196, P=0.048) and GRACE risk score (r=-0.321, P=0.001). Bioinformatic analysis suggested that cSMARCA5 might be involved in the process of AMI through regulating the gene expression of tumor necrosis factor. Conclusions: The expression of cSMARCA5 is significantly decreased in peripheral blood of AMI patients compared with control group, and its expression level is negatively correlated with the severity of myocardial infarction. cSMARCA5 is expected to be a potential biomarker of AMI.
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Infarto do Miocárdio , RNA Circular , Masculino , Humanos , Estudos de Casos e Controles , Relevância Clínica , Volume Sistólico , Função Ventricular Esquerda , Infarto do Miocárdio/diagnóstico , Creatina Quinase Forma MB/metabolismo , BiomarcadoresRESUMO
By analyzing the epidemic characteristics of influenza during the COVID-19 epidemic in Jiangsu Province from 2020 to 2022, it found that 90 721 influenza-like case samples were collected in Jiangsu Province from 2020 to 2022, of which 6 732 were nucleic acid-positive samples, with an average positive detection rate of 7.4% in three years. The annual positive detection rate presented a U-shaped distribution, with positive detection rates of 4.4%, 3.2% and 14.7%, respectively, with statistically significant differences (χ2=12 126.00, P<0.001). During the seasonal peak period of influenza from 2020 to 2022, there was a significant decrease in the intensity of the two influenza activity peaks that occurred before the virus became fully prevalent in the population. The first peak occurred from January to February 2020, and the positive detection rate of influenza nucleic acid decreased from 54.4% (317/583) in the third week to 2.1% (12/584) in the eighth week, with a statistically significant difference (χ2=394.49, P<0.001). The second occurred in December 2022, and the positive detection rate of influenza nucleic acid decreased from 14.9% (90/605) at the 49th week to 1.9% (11/572) at the 52nd week, with a statistically significant difference (χ2=62.88, P<0.001). The influenza epidemic in Jiangsu Province from 2020 to 2022 had obvious seasonal characteristics, and the distribution differences of influenza virus-positive cases in each month were statistically significant (χ2=858.00, P<0.001), with two epidemic peaks each year: winter, spring (December to March of the following year), and summer, and autumn (July to November). The epidemic strains were the B-V strain and seasonal H3 strain, respectively. There was a statistically significant difference in the positive detection rate of influenza cases detected in different age groups (χ2=60.00, P<0.001). The age group between 5 and 14 years old had the highest influenza-positive detection rate (10.4%), while the age group≥60 years old had a relatively low influenza-positive detection rate (5.1%). The positive detection rate decreased with the increase in the age group (Ztrend=12.82, P<0.001).
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COVID-19 , Epidemias , Influenza Humana , Ácidos Nucleicos , Humanos , Pré-Escolar , Criança , Adolescente , Influenza Humana/epidemiologia , COVID-19/epidemiologia , Estações do AnoRESUMO
Methomyl is a carbamate insecticide widely used in pesticides. Most of the poisoning methods are through digestive tract, respiratory tract and skin contact. At present, there is no report of poisoning caused by intramuscular injection. A case of poisoning caused by intramuscular injection of methomyl was analyzed retrospectively. About 4 minutes later, cholinergic crisis and central inhibition occurred. Venovenous-Extracorporeal Membrane Oxygenation (VV-ECMO) and atropine were given quickly. Finally, the patient was successfully rescued and had a good prognosis. After intramuscular injection of methomyl, cholinergic crisis can occur rapidly, and the onset rate is significantly faster than that of digestive tract, respiratory tract and skin contact.
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Inseticidas , Praguicidas , Humanos , Estudos Retrospectivos , Metomil , ColinérgicosRESUMO
Objective: To understand the related factors of new-type drug use and recent HIV infection among men who have sex with men (MSM), and provide a reference for formulating targeted strategies for HIV/AIDS prevention and control. Methods: MSM were recruited in sentinel surveillance sites of nine cities in Shandong province from April to July 2021, with a sample size of 400 in each city. A face-to-face questionnaire was conducted to collect demographic characteristics, high-risk behaviors, acceptance of HIV intervention services, etc. Blood samples were collected for HIV and syphilis antibodies detection. Limiting-antigen avidity enzyme immunoassay (LAg-Avidity EIA) was used to detect recent HIV infection, and the rate of recent HIV infection was calculated. Results: 3 624 MSM were under study with the following characteristics as: aged (32.70±9.33) years old, the aged 30 and above (59.52%, 2 157/3 624), with high school education or below (55.99%, 2 029/3 624), being unmarried/divorced/widowed (57.70%, 2 091/3 624) and as having homosexual orientation (86.26%, 3 126/3 624) accounted for the more mainly. Of 32.95% (1 194/3 624) had same-sex unprotected anal sex in recent six months; 27.48% (993/3 613) ever used new-type drugs, and the HIV antibody positive rate was 3.12% (113/3 624). The recent HIV infection rate appeared as 2.61% (95%CI: 1.73%-3.49%). The multivariable logistic regression analysis indicated that the related factors of new-type drug use were unmarried/divorced/widowed (compared with being married/cohabitating, aOR=1.43, 95%CI: 1.22-1.69), educational level of college or above (compared with educational level of high school or below, aOR=1.47, 95%CI: 1.25-1.72), mainly through the Internet/dating software to find male sex partners (compared with mainly through bars/baths/parks and other places to find male sex partners, aOR=1.76, 95%CI: 1.41-2.19). Those who had unprotected anal sex in the last six months (compared with no unprotected anal sex, aOR=1.33, 95%CI: 1.13-1.57), had sexually transmitted diseases in the past year (compared with no sexually transmitted disease, aOR=2.77, 95%CI: 2.04-3.76) were more likely to use new-type drugs. The multinominal logistic regression showed that MSM who had unprotected anal sex in the last six months (compared with no unprotected anal sex, aOR=2.51, 95%CI: 1.25-5.01) or did not receive HIV intervention services in the past year (compared with those who received HIV intervention services, aOR=3.89, 95%CI: 1.30-11.60), were syphilis positive (compared with syphilis negative, aOR=8.18, 95%CI: 2.98-22.48), used new-type drugs (compared with those who did not use new-type drugs, aOR=4.75, 95%CI: 2.32-9.70) had a higher risk of recent HIV infection. Conclusions: New-type drugs have been widely used in MSM in Shandong province. The abuse of new-type drugs increases the risk of recent HIV infection.
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Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias , Sífilis , Masculino , Humanos , Adulto Jovem , Adulto , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Transtornos Relacionados ao Uso de Substâncias/epidemiologiaRESUMO
Objective: To reveal the crucial toxic components of ambient fine particles (PM2.5) that affect the maturation and differentiation of megakaryocytes. Methods: Human megakaryocytes were exposed to the organic fractions, metallic fractions and water-soluble fractions of PM2.5 at two exposure doses (i.e. actual air proportion concentration or the same concentration), respectively. The cell viability was performed to screen the non-cytotoxic levels of toxic components of PM2.5 using the CCK-8 assay. CellTiter-Blue assay, morphological observation, flow cytometry analysis and WGA staining assay were used to evaluate the cell morphological changes, occurrence of DNA ploidy, alteration in the expressions of biomarkers and platelet formation, which were key indicators of the maturation and differentiation of megakaryocytes. Results: Compared to the control group, both metallic and organic components of PM2.5 resulted in a lag in megakaryocytes with an increase in cell volume and the onset of DNA ploidy. Flow cytometry analysis showed that CD33 (the marker of myeloid-specific) decreased and CD41a (a megakaryocyte maturation-associated antigen) increased in metallic and organic components of PM2.5 treatment groups. Moreover, compared to the control group, budding protrusions increased in metallic and organic components of PM2.5 treatment groups. The water-soluble components had no effect on the maturation and differentiation of macrophages. Conclusion: Metallic and organic components of PM2.5 are the crucial toxic components that promote the maturation and differentiation of megakaryocytes.
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Megacariócitos , Biomarcadores , DNA/análise , DNA/farmacologia , Humanos , Megacariócitos/química , Material Particulado/toxicidade , Água/farmacologiaRESUMO
Objective: To investigate the clinicopathological features of proliferations with mesonephric features (PMF) of the gynecologic tract. Methods: A retrospective analysis was performed on the clinical and pathological data of 16 cases with PMF that were diagnosed from October 2016 to January 2022 at a single institution. The relevant literature was reviewed. Results: Among the 16 cases, with an average of 53 years (31-68 years), there were 5 cases of mesonephric hyperplasia, 4 cases of mesonephric adenocarcinoma and 7 cases of mesonephric-like adenocarcinoma. The five cases of mesonephric hyperplasia were located in the lateral wall of the cervix and composed of simple tubules with growth patterns of diffuse or lobular clusters, without obvious stromal reaction. Four cases of mesonephric adenocarcinoma consisted of a mixture of papillary, cribriform, solid and other architectures, the nuclei resembling these of papillary thyroid carcinoma, and strong fibroproliferative reaction. They were located deep in the cervical and vaginal stroma. One of the tumors showed atypical mesonephric hyperplasia adjacent to the tumor. Five uterine and two ovarian mesonephric-like adenocarcinoma cases had similar histological morphology with mesonephric adenocarcinoma, but no mesonephric remnants/mesonephric hyperplasia were found near the tumors. In addition, four (4/5) uterine mesonephric-like adenocarcinoma cases originated from the endometrium with secondary involvement of myometrium, including one case with clear demarcation between the normal endometrium and the neoplastic glands. One (1/5) uterine mesonephric-like adenocarcinoma case was mainly located in the deep myometrium, along with adenomyosis around the tumor, without mesonephric remnants. Two ovarian mesonephric-like adenocarcinoma cases were associated with endometriotic cyst/endometrioid cystadenoma, including one case with an abrupt transition between normal epithelium and atypical mesonephric cells within the single individual cyst directly adjacent to tumor. All mesonephric hyperplasia and mesonephric adenocarcinoma cases were positive for GATA3, PAX8 and CD10 in a varying degree, and negative for ER, PR and TTF1. Although mesonephric-like adenocarcinoma showed a considerable overlap of immunohistochemical expression with mesonephric adenocarcinoma, seven mesonephric-like adenocarcinoma cases were positive for TTF1 and negative for GATA3. Conclusions: PMF is a class of rare proliferative lesions with morphological and immunophenotypic characteristics of mesonephric duct. Its commonly involved site, microscopic morphology, associated benign and/or atypical lesions, and immunophenotype may contribute to its diagnosis and differential diagnosis.
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Adenocarcinoma , Lesões Pré-Cancerosas , Adenocarcinoma/patologia , Biomarcadores Tumorais/análise , Colo do Útero/patologia , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia/patologia , Lesões Pré-Cancerosas/patologia , Estudos RetrospectivosRESUMO
In recent years, chlorfenapyr poisoning has gradually increased in clinical practice, but the case fatality rate remains high. At present, the research on its poisoning mechanism and clinical characteristics is limited, and there is no effective treatment. In order to summarize the clinical characteristics of chlorfenapyr poisoning, in order to guide the clinical treatment, this article reported 2 cases of acute chlorfenayr poisoning and 21 cases of literature review, and summarized the clinical characteristics of chlorfenapyr poisoning.Most of the symptoms of gastrointestinal symptoms, profuse sweating, high fever, and changes in consciousness after chlorfenapyr poisoning, and delayed exacerbations are common, which can involve multiple organ systems such as the central nervous system, providing a basis for clinical diagnosis and treatment.
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Inseticidas , PiretrinasRESUMO
Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.
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Criptorquidismo , Transtornos do Desenvolvimento Sexual , Hipospadia , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Criança , China/epidemiologia , Criptorquidismo/genética , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/genética , Feminino , Doenças dos Genitais Masculinos , Genótipo , Humanos , Hipospadia/genética , Masculino , Proteínas de Membrana/genética , Pênis/anormalidades , Fenótipo , Estudos Retrospectivos , Esteroide 21-Hidroxilase/genéticaRESUMO
The article "Protective effect of miR-146 against kidney injury in diabetic nephropathy rats through mediating the NF-κB signaling pathway", H.-Y. Yu, L.-F. Meng, X.-H. Lu, L.-H. Liu, X. Ci, Z. Zhuo, published in Eur Rev Med Pharmacol Sci 2020; 24 (6): 3215-3222-DOI: 10.26355/eurrev_202003_20688-PMID: 32271439, has been retracted by the authors due to some inaccuracies (some data cannot be repeated by further research). The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20688.
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In order to discuss the necessity of repeated renal arteriography in the treatment of severe bleeding after percutaneous nephrolithotomy, this study retrospectively analyzed the clinical data of patients with severe bleeding after percutaneous nephrolithotomy in the Department of Urology Surgery of the First Hospital of China Medical University from August 2010 to July 2020, summarily analyzing treatments, outcomes and follow-up results of 27 patients who were treated by renal arteriography more than twice. Of these 27 patients who underwent repeated renal arteriography, 23 of them were treated by two times, 4 by three times, all of whom were diagnosed as renal vascular injury. And 15 of them were diagnosed as pseudoaneurysm, 4 of them renal arteriovenous fistula, and 8 of them pseudoaneurysm combined with renal arteriovenous fistula. After clear diagnosis, all these patients were performed with renal artery embolization, after which the symptoms of hematuria and lumbar discomfort were relieved or disappeared immediately. These patients were followed up from 6 months to 5 years, without corresponding symptoms recurring and with the renal function equivalent to that before embolization. The results showed that repeated renal arteriography was of great significance in the treatment of patients with severe bleeding after percutaneous nephrolithotomy, helping to clarify the cause of bleeding and giving appropriate and timely treatment.
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Nefrolitotomia Percutânea , Nefrostomia Percutânea , Angiografia , Hemorragia , Humanos , Nefrolitotomia Percutânea/efeitos adversos , Estudos RetrospectivosRESUMO
Objective: To investigate the influence of digital light processing (DLP) and computer numerical controlmilling (CNC) on the mechanical behavior of zirconia. Methods: Prepared DLP samples (experimental group, n=52) and CNC samples (control group, n=52) with 12 samples in each group were randomly selected using random number table to measure density, grain size and crystal phase composition. According to the different methods fracture toughness test, the samples were divided into indentation method group (IM) and single-edge-V-notch-beam group (SEVNB), with 30 DLP and 30 CNC samples in IM group, 10 DLP and 10 CNC samples in SEVNB group. The IM group was tested under three different loads (49.03 N, 98.07 N, 196.10 N), there were 10 samples for each load and each sample was tested at 15 points, and the load with the ratio of crack length to indentation diagonal length greater than 2.5 was selected as the indentation load to calculate its IM fracture toughness. At the same time, the SEVNB group was tested with four point bending test to record the maximum load at the time of fracture and calculate the SEVNB fracture toughness. Finally, the indentation and fracture surface were observed using optical microscope and scanning electron microscope, and the results of DLP group and CNC group were further compared to explore the difference in fracture mechanism. Results: The microstructure of DLP and CNC zirconia was basically the same, the density of DLP group was (6.020±0.021) g/cm3, the grain size was (0.603±0.033) µm; the density of CNC group was (6.038±0.012) g/cm3, the grain size was (0.591±0.033) µm. Both groups were composed of tetragonal zirconia. The load of 196.10 N was chosen as the indentation load for two groups to calculate the IM fracture toughness. In terms of fracture toughness, there was no significant difference between the two groups (P>0.05). Scanning electron microscope images of fracture surface showed the intergranular fracture was the leading fracture mode of two groups. The IM and SEVNB fracture toughness of DLP zirconia were (6.111±0.179) MPa·m1/2 and (7.221±0.809) MPa·m1/2, respectively. The IM and SEVNB fracture toughness of CNC zirconia were (6.126±0.383) MPa·m1/2 and (7.408±0.533) MPa·m1/2, respectively. Conclusions: The microstructure of DLP and CNC zirconia is almost the same, and there is little difference in the fracture toughness of zirconia between two processing technologies.
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Impressão Tridimensional , Zircônio , Cerâmica , Materiais Dentários , Porcelana Dentária , Teste de Materiais , Propriedades de SuperfícieRESUMO
We have developed a software package, namely, PASP (Property Analysis and Simulation Package for materials), to analyze the structural, electronic, magnetic, and thermodynamic properties of complex condensed matter systems. Our package integrates several functionalities including symmetry analysis, global structure searching methods, effective Hamiltonian methods, and Monte Carlo simulation methods. In conjunction with first-principles calculations, PASP has been successfully applied to diverse physical systems. In this paper, we give a brief introduction to its main features and underlying theoretical formulism. Some typical applications are provided to demonstrate the usefulness, high efficiency, and reliability of PASP. We expect that further developments will make PASP a general-purpose tool for material simulation and property calculation of condensed matters.
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Objective: To evaluate the influence of the sleeve lengths and implant lengths on accuracy of static computer-assisted implant surgery (sCAIS). Methods: Twenty-eight models of bilateral mandibular single tooth loss were included. Fifty-five implants were placed under the guidance of sCAIS (Straumann Bone Level 4.1 mm×10 mm). According to the height of metal sleeve of static guide plate, 55 implants were divided into 11 groups (free hand group, 1 mm group, 2 mm group, 3 mm group, 4 mm group, 5 mm group, 6 mm group, 7 mm group, 8 mm group, 9 mm group, 10 mm group), with 5 implants in each group. Eight research models were included. Group with 5 mm sleeve guides were used to place implants of different length, (Straumann Bone Level width 4.1 mm, height was 8 mm, 10 mm and 14 mm), 5 implants in each group. Eighteen patients with mandibular single tooth loss were included in the Department of Oral Implantology, Tianjin Stomatological Hospital from October 2018 to June 2019. There were 10 males and 8 females, 18-46(33.7±7.9) years old. A total of 18 implants were implanted and divided into 3 groups (free hand group, 3 mm group and 5 mm group) with 6 implants in each group. Digital software was used to compare the implant positions before and after implantation. Non-parametric Kruskal-Wallis test or one-way ANOVA were used to analyze the results. Results: There was no significant difference in implant vertical deviation between different sleeve height groups (1-10 mm) and free hand group, but the neck deviation in free hand group[(1.04±0.13) mm] was significantly higher than that in different sleeve height groups (1-10 mm) (P<0.05). The tip deviations of free hand group, 1 mm group and 2 mm group [(1.32±0.43), (0.83±0.10) and (0.78±0.11) mm, respectively] was significantly higher than that of 10 mm group [(0.31±0.14) mm](P<0.05). The angle deviation of free hand group and 1 mm group (3.99°±0.85° and 2.59°±0.69°), respectively] was significantly higher than that of 10 mm group (0.61°±0.03°) (P<0.05). The tip deviations of implants in the 14 mm group [(0.83±0.22) mm] was significantly higher than that in the 8 mm and 10 mm groups [(0.44±0.07) and (0.49±0.06) mm, respectively]. Clinical studies showed that there was no significant difference in neck deviation, tip deviation and angle deviation between 3 mm group and 5 mm group (P>0.05), but deviations were significantly lower than those in free hand group (P<0.05). Conclusions: The length of the sleeves has significant influence on the accuracy of the surgical guide. There was no significant difference in accuracy of the implant guide with 3 mm or 5 mm metal sleeves. The vitro study has some limitations and needs further systematic research.
Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Perda de Dente , Adolescente , Adulto , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea , Feminino , Humanos , Imageamento Tridimensional , Masculino , Mandíbula/cirurgia , Pessoa de Meia-Idade , Adulto JovemRESUMO
Accurate and measurable tooth preparation under the principle of protecting dental tissue, vital pulp and periodontal tissue health is a challenging procedure in esthetic dental restoration. The traditional protocol of tooth preparation often leads to complications after restoration because of the lack of precise preparation control. The pre-operative analysis and design, intraoperative guidance and sequence guidance technology of post-operative prosthesis production, with the target restoration space (TRS) as the core and digital technology as the support technology, embody the numerical requirements of the prosthesis space based on the actual measurement, and will lay the core foundation of the future digital prosthodontics. This paper introduces the new understanding of tooth preparation guidance, the classification and application of digital guides, the practice of micro tooth preparation guided by digital template, and summarizes the development direction of prosthodontics from experience guidance to digital guidance.