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An embedded spherical dot taper structure (EDT) based on the MZI principle is proposed in this paper, which is mainly fabricated by using two special arc discharges in the preparation process. The proposed structure involves two specialized arc discharge techniques. First, an oversaturated discharge fusion process creates a micro-arc spherical area on the fiber end face to form the first link type. Second, an unsaturated discharge-pulling taper fusion joint creates a local micro-extrusion operation on this micro-arc fiber end face to form the second link. The thermal stress from instantaneous discharge causes a reverse spherical expansion zone to form in the end face structure, similar to the micromachining of long-period fiber gratings that use local CO2 laser etching to create modulated zones. The study involves a mathematical and theoretical analysis of how geometric parameters in the spherical modulation zone impact the structure's characteristic spectrum. The research demonstrates the potential for this structure to function as a light-intensity modulated strain sensor device through both theoretical and experimental means. As per the experimental findings, the optimized structure displays a high level of strain sensing sensitivity at 0.03â dB/µÎµ and temperature sensing sensitivity of 73 pm/°C (20°C-75°C) and 169 pm/°C (75°C-120°C). Additionally, it possesses excellent cross-sensitivity at only â¼0.0015 µÎµ/°C. Therefore, this sensor presents a favorable option for strain and temperature synchronization sensing and monitoring components, and exhibits notable application prospects in precision engineering, which encompasses mechanical manufacturing, the power and electrical industry, healthcare domain, and certain specialized areas of small-scale precision engineering.
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OBJECTIVE: To observe the dynamic change in expression of protease-activated receptor 2 (PAR2) during onset and progression of liver fibrosis by using a rat model. METHODS: A cholestatic liver fibrosis model was established in Sprague-Dawley rats (aged 8-9 weeks, body weight 350 - 400 g) by bile duct ligation surgery. Rats receiving a sham operation and unoperated rats served as the negative and normal control groups, respectively. At baseline (pre-surgery) and post-surgery weeks 2, 4, 6, and 8, five rats from each group were sacrificed for whole liver resection. The protein and mRNA expressions of PAR2 and collagen I/III were detected by western blotting and RT-PCR, respectively. Between-group differences were assessed by analysis of variance testing. RESULTS: At post-surgery week 2, the liver fibrosis group showed higher expression of PAR2 mRNA and protein than either control group. The expression levels of PAR2 continued to rise over time in the liver fibrosis group (peaking at week 8), and were significantly higher than those detected in the control groups (weeks 4-6: P less than 0.05; week 8, P less than 0.05). A similar trend was observed for the expression of collagen I/III. CONCLUSION: Dynamic expression of PAR2 observed in a cholestatic liver fibrosis rat model may indicate a role for this factor in the formation of liver fibrosis.
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Cirrose Hepática Biliar/metabolismo , Fígado/metabolismo , Receptor PAR-2/metabolismo , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Fígado/patologia , Cirrose Hepática Biliar/patologia , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To elucidate the therapeutic effect of subtemporal decompressive craniotomy with large flap resection on serious craniocerebral injury associated with cerebral infarction. METHODS: Forty-eight cases of serious head injury accompanied by cerebral infarction were classified into two groups with each having 24 cases: treatment group, in which large bone-flap decompressive craniotomy was performed; control group, in which routine craniotomy and hematoma evacuation were adopted. The status of cerebral infarction pre- and post-operation, as well as the curative effect 3 months after operation were comparatively analysed between the two groups. RESULTS: There was no significant difference regarding the status of cerebral infarction on the first day after operation; while one week after operation, the size of cerebral infarction was significantly smaller in treatment group than control one (P less than 0.05). Postoperative 3 months, the mortality rate was 20.8% in treatment group, being evidently superior to that of control group (33.3%, P less than 0.05). The mo- derate disability (good and fair) rate was 41.7% in treatment group, significantly higher than that in control group (25.0%, P less than 0.05). CONCLUSION: Large bone-flap decompressive craniotomy is confirmed effective and hence it offers us a preferable alternative of treatment by which to reduce disability and fatality rates for patients with serious head injury accompanied by cerebral infarction.
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Infarto Cerebral , Craniotomia , Traumatismos Craniocerebrais , Descompressão Cirúrgica , Humanos , Retalhos CirúrgicosRESUMO
Background: Globally, several generations of doctors in the field of lymphedema have created numerous publications. To date, no bibliometric analysis has been performed specifically on these publications. For the further promotion of research on lymphedema and to align with the international research frontiers, it is essential to understand the current state of Lymphedema research output. Objective: This study aims to statistically and visually analyze the characteristics of publications output, distribution of contributions and development process of lymphedema, enriching the knowledge base of Lymphedema, and then seek potential research topics and collaborators. Methods: Based on the Web of Science core collection database, we firstly analyzed the quantity and quality of publications in the field of lymphedema, secondly profiled the publishing groups in terms of country, institution, author's publication and cooperation network, and finally sorted out and summarized the hot topics of research. Results: A total of 8569 papers were retrieved from 1900-2021. The top4 journals with the most publications were LYMPHOLOGY, LYMPHATIC RESEARCH AND BIOLOGY, PLASTIC AND RECONSTRUCTIVE SURGERY and ANNALS OF SURGICAL ONCOLOGY. The top 4 countries with the most publications were USA, Japan, UK, and China. The United States dominates the total number of publications and the international cooperation network. The most productive research institution is Harvard University, and the research institution with the most collaborating institutions is Memorial Sloan Kettering Cancer Center. Mortimer, Peter S contributes the most research in this field. The research achievements of Japanese scholars in this field are of great significance. The top 5 ranked keywords are "Breast Cancer", "Health-Related Quality Of Life", "Lymphscintigraphy", "Lymphovenous Anastomosis", and "Lymphangiogenesis". Conclusion: More and more scholars are devoted to the research of cancer-related Lymphedema. It is foreseeable that breast cancer-related lymphedema and lymphangiogenesis will remain a focus of future research. Advances in Lymphatic vessel imaging and the development of lymphatic microsurgery will further play a role in the clinical workup of lymphedema. Meanwhile, This study can help researchers identify potential collaborators and partner institutions and contribute to further research.
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BACKGROUND: Cerebral ischemia-reperfusion injury (CIRI) refers to a secondary brain injury that can occur when the blood supply to the ischemic brain tissue is restored. However, the mechanism underlying such injury remains elusive. METHODS: The 150 male C57 mice underwent middle cerebral artery occlusion (MCAO) for 1 h and reperfusion for 24 h, Among them, 50 MCAO mice were further treated with Mitochondrial division inhibitor 1 (Mdivi-1) and 50 MCAO mice were further treated with N-acetylcysteine (NAC). SH-SY5Y cells were cultured in a low-glucose culture medium for 4 h under hypoxic conditions and then transferred to normal conditions for 12 h. Then, cerebral blood flow, mitochondrial structure, mitochondrial DNA (mtDNA) copy number, intracellular and mitochondrial reactive oxygen species (ROS), autophagic flux, aggresome and exosome expression profiles, cardiac tissue structure, mitochondrial length and cristae density, mtDNA and ROS content, as well as the expression of Drp1-Ser616/Drp1, RIP1/RIP3, LC3 II/LC3 I, TNF-α, IL-1ß, etc., were detected under normal or Drp1 interference conditions. RESULTS: The mtDNA content, ROS levels, and Drp1-Ser616/Drp1 were elevated by 2.2, 1.7 and 2.7 times after CIRI (P < 0.05). However, the high cytoplasmic LC3 II/I ratio and increased aggregation of p62 could be reversed by 44% and 88% by Drp1 short hairpin RNA (shRNA) (P < 0.05). The low fluorescence intensity of autophagic flux and the increased phosphorylation of RIP3 induced by CIRI could be attenuated by ROS scavenger, NAC (P < 0.05). RIP1/RIP3 inhibitor Necrostatin-1 (Nec-1) restored 75% to a low LC3 II/LC3 I ratio and enhanced 2 times to a high RFP-LC3 after Drp1 activation (P < 0.05). In addition, although CIRI-induced ROS production caused no considerable accumulation of autophagosomes (P > 0.05), it increased the packaging and extracellular secretion of exosomes containing p62 by 4 - 5 times, which could be decreased by Mdivi-1, Drp1 shRNA, and Nec-1 (P < 0.05). Furthermore, TNF-α and IL-1ß increased in CIRI-derived exosomes could increase RIP3 phosphorylation in normal or oxygen-glucose deprivation/reoxygenation (OGD/R) conditions (P < 0.05). CONCLUSIONS: CIRI activated Drp1 and accelerated the p62-mediated formation of autophagosomes while inhibiting the transition of autophagosomes to autolysosomes via the RIP1/RIP3 pathway activation. Undegraded autophagosomes were secreted extracellularly in the form of exosomes, leading to inflammatory cascades that further damaged mitochondria, resulting in excessive ROS generation and the blockage of autophagosome degradation, triggering a vicious cycle.
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Isquemia Encefálica , Exossomos , Traumatismo por Reperfusão , Animais , Infarto Cerebral , DNA Mitocondrial , Exossomos/metabolismo , Glucose , Humanos , Inflamação , Masculino , Camundongos , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Reperfusão , Fator de Necrose Tumoral alfaRESUMO
G-quadruplex DNA (G4DNA) structure, which widely exists in the chromosomal telomeric regions and oncogenic promoter regions, plays a pivotal role in extending telomeric DNA with the help of telomerase in human cells. Bloom (BLM) helicase, a crucial member of the family of genome surveillance proteins, plays an essential role in DNA metabolic and repair pathways, including DNA replication, repair, transcription, recombination during chromosome segregation, and assuring telomere stability. The unwinding of G4DNA requires the participation of DNA helicase, which is crucial for maintaining chromosomal stability in cancer cells. Using fluorescence polarization and the electrophoretic mobility shift assay (EMSA), this study aimed to investigate the DNA-binding and unwinding properties of BLM helicase, cloned and purified from prostate cancer cells, toward G4DNA. The results revealed that BLM helicase derived from prostate cancer cells could bind and unwind G4DNA. The molecular affinity of bond between G4DNA and the helicase was dependent on the single-stranded DNA (ssDNA) terminals in G4DNA; the helicase was effectively bound to the G4DNA when the helicase monomer sufficiently covered approximately 10 nucleotides at the 3' or 5' ssDNA tail of G4DNA. For the unwinding of G4DNA, there was an apparent requirement of a 3' ssDNA tail and ATP; a G4DNA with only a 3' ssDNA tail was identified to be the most suitable substrate to be unwound by BLM helicase and required 3' ssDNA tails of at least 10 nt in length for efficient unwinding. Besides, BLM helicase was loosely bound and partly unwound the blunt-ended G4DNA. Although further mechanistic studies are warranted, the experimental results presented in this study are beneficial to further our understanding of the functional implication of BLM helicase in prostate cancer cells.
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DNA/química , Quadruplex G , Neoplasias da Próstata/metabolismo , RecQ Helicases/metabolismo , Telômero/metabolismo , DNA/genética , DNA/metabolismo , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Humanos , Cinética , Masculino , Modelos Moleculares , Conformação de Ácido Nucleico , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ligação Proteica , RecQ Helicases/genética , Especificidade por Substrato , Telômero/genéticaRESUMO
In this study, three new germacranolide sesquiterpenes (1-3), together with six related known analogues (4-9) were isolated from the whole plant of Carpesium cernuum. Their structures were established by a combination of extensive NMR spectroscopic analysis, HR-ESIMS data, and ECD calculations. The anti-leukemia activities of all compounds towards three cell lines (HEL, KG-1a, and K562) were evaluated in vitro. Compounds 1-3 exhibited moderate cytotoxicity with IC50 values ranging from 1.59 to 5.47 µmol·L-1. Mechanistic studies indicated that 2 induced apoptosis by decreasing anti-apoptotic protein Bcl-2 and activating the caspase family in K562 cells. These results suggest that compound 2 is a potential anti-leukemia agent.
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Antineoplásicos Fitogênicos , Asteraceae , Sesquiterpenos de Germacrano/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Compostos Fitoquímicos/farmacologiaRESUMO
OBJECTIVE: To retrospectively analyze 95 cases of traumatic carotid cavernous fistula treated by endovascular embolization. METHODS: From January 1994 to December 2008, 95 patients with traumatic carotid cavernous fistula were treated in our hospital. All patients received selective cerebral angiography through femoral artery catheterization. Accordingly, 89 cases were treated by detachable balloon embolization, 5 by platinum microcoils and 1 by covered-stent, respectively. RESULTS: In the study, 61 cases achieved successful balloon embolization at the first time. Fifty-six cases had multiple balloons due to the big fistula. Nine cases received balloon embolization twice. But among the 5 patients treated with platinum microcoils, one developed slight brainstem ischemia. After operation the patient had hemiparesis and swallow difficulty, but gradually recovered 3 months later. No neurological deficits were observed in other cases. All the cases recovered. Eighty-five cases were followed up for 1-15 years and no recurrence was found. CONCLUSIONS: The endovascular embolization for traumatic carotid cavernous fistula is minimally invasive, safe, effective and reliable. The detachable balloon embolization is the first choice in the treatment of TCCF.
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Oclusão com Balão/métodos , Fístula Carótido-Cavernosa/terapia , Embolização Terapêutica/métodos , Adolescente , Adulto , Idoso , Fístula Carótido-Cavernosa/diagnóstico , Criança , Emergências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , StentsRESUMO
OBJECTIVE: To investigate the relationship between hematoma ventricle distance (HVD) and clinical outcome in patients with intracerebral hemorrhage (ICH). METHODS: We prospectively enrolled consecutive patients with ICH in a tertiary academic hospital between July 2011 and April 2018. We retrospectively reviewed images for all patients receiving a computed tomography (CT) within 6 h after onset of symptoms and at least one follow-up CT scan within 36 h. The minimum distance of hematoma border to nearest ventricle was measured as HVD. Youden index was used to evaluate the cutoff of HVD predicting functional outcome. Logistic regression model was used to assess the HVD data and clinical poor outcome (modified Rankin Scale 4-6) at 90 days. RESULTS: A total of 325 patients were included in our final analysis. The median HVD was 2.4 mm (interquartile range, 0-5.7 mm), and 119 (36.6%) patients had poor functional outcome at 3 months. After adjusting for age, admission Glasgow coma scale, intraventricular hemorrhage, baseline ICH volume, admission systolic blood pressure, blood glucose, hematoma expansion, withdrawal of care, and hypertension, HVD ≤ 2.5 mm was associated with increased odds of clinical poor outcome [odd ratio, 3.59, (95%CI = 1.72-7.50); p = 0.001] in multivariable logistic regression analysis. CONCLUSION: Hematoma ventricle distance allows physicians to quickly select and stratify patients in clinical trials and thereby serve as a novel and useful addition to predict ICH prognosis.
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Mythimna separata (Walker) moths captured in light traps were monitored in Luohe, central-northern China, from 1980 to 2016. Annual average temperature recorded an increase of 0.298°C/10 years in this region in the period. Our results indicate that a rising April and May average temperature and earlier occurrences of days recording the highest day temperature (30°C) caused an advanced peak and increasing proportion of high ovarian development levels of first-generation females in earlier summers. Results using Johnson's formulation of "oogenesis-flight syndrome" indicate that increasing sexual maturity proportion has resulted in more emigrant individuals in the local first-generation moth becoming residents, and then increased individuals rapidly in the local second-generation moth since 2006. Consequences of this action have a boom in corn damage since 2007 in this region. Advanced peak dates of the first and second-generation moth revealed the same response to increasing average monthly temperatures in the monitoring period. Increasing temperatures, the average May temperature exceeds or equal to 22°C, during the early 2000's may represent a physiological threshold for M. separata development. Our results suggest that climate warming may impact M. separata migratory status and cause a problem of crop production in this region.
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The lung cancer incidence in the Xuanwei and neighboring region, Yunnan, China, is among the highest in China and is attributed to severe air pollution with high benzo(a)pyrene levels. We systematically and comparatively analyzed DNA methylation alterations at genome and gene levels in Xuanwei lung cancer tissues and cell lines, as well as benzo(a)pyrene-treated cells and mouse samples. We obtained a comprehensive dataset of genome-wide cytosine-phosphate-guanine island methylation in air pollution-related lung cancer samples. Benzo(a)pyrene exposure induced multiple alterations in DNA methylation and in mRNA expressions of DNA methyltransferases and ten-11 translocation proteins; these alterations partially occurred in Xuanwei lung cancer. Furthermore, benzo(a)pyrene-induced DKK2 and EN1 promoter hypermethylation and LPAR2 promoter hypomethylation led to down-regulation and up-regulation of the genes, respectively; the down-regulation of DKK2 and EN1 promoted the cellular proliferation. Thus, DNA methylation alterations induced by benzo(a)pyrene contribute partially to abnormal DNA methylation in air pollution-related lung cancer, and these DNA methylation alterations may affect the development and progression of lung cancer. Additionally, vitamin C and B6 can reduce benzo(a)pyrene-induced DNA methylation alterations and may be used as chemopreventive agents for air pollution-related lung cancer.
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Poluição do Ar/efeitos adversos , Metilação de DNA , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Animais , Anticarcinógenos/farmacologia , Ácido Ascórbico/farmacologia , Benzo(a)pireno/administração & dosagem , Benzo(a)pireno/toxicidade , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Vitamina B 6/farmacologiaRESUMO
Eleven triterpenoids were isolated from the fruits of Phellodendron chinense Schneid, and their structures were determined by spectroscopic analysis. The results show that four new tirucallane-type triterpenoids 1, 2, 5, and 6 and seven known compounds 3, 4, 7, 8, 9, 10, and 11 were isolated. Structurally, compound 6 was uncommon; it has a chlorine atom instead of a methyl group at the C-20 position. The cytotoxicities of the compounds was evaluated against the in vitro proliferation of four human tumor cell lines HEL, K562, MDA, and PC3 using adriamycin as the positive control. Compound 1 showed a similar cytotoxicity as the positive control; compounds 3 and 10 showed moderate cytotoxicities compared to the control (P<0.05). This indicates that these compounds have great potential for the development of new antitumor drugs.
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Antineoplásicos Fitogênicos/química , Frutas/química , Phellodendron/química , Triterpenos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Extratos Vegetais/química , Triterpenos/isolamento & purificaçãoRESUMO
Air pollution has been classified as Group 1 carcinogenic to humans, but the underlying tumorigenesis remains unclear. In Xuanwei City of Yunnan Province, the lung cancer incidence is among the highest in China attributed to severe air pollution generated by combustion of smoky coal, providing a unique opportunity to dissect lung carcinogenesis of air pollution. Here we analyzed the somatic mutations of 164 non-small cell lung cancers (NSCLCs) from Xuanwei and control regions (CR) where smoky coal was not used. Whole genome sequencing revealed a mean of 289 somatic exonic mutations per tumor and the frequent C:G â A:T nucleotide substitutions in Xuanwei NSCLCs. Exome sequencing of 2010 genes showed that Xuanwei and CR NSCLCs had a mean of 68 and 22 mutated genes per tumor, respectively (p < 0.0001). We found 167 genes (including TP53, RYR2, KRAS, CACNA1E) which had significantly higher mutation frequencies in Xuanwei than CR patients, and mutations in most genes in Xuanwei NSCLCs differed from those in CR cases. The mutation rates of 70 genes (e.g., RYR2, MYH3, GPR144, CACNA1E) were associated with patients' lifetime benzo(a)pyrene exposure. This study uncovers the mutation spectrum of air pollution-related lung cancers, and provides evidence for pollution exposure-genomic mutation relationship at a large scale.
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Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Benzo(a)pireno/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Idoso , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Transformação Celular Neoplásica , Carvão Mineral/efeitos adversos , Exposição Ambiental/efeitos adversos , Feminino , Frequência do Gene/genética , Genoma/genética , Humanos , Neoplasias Pulmonares/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Mutação/genética , Taxa de Mutação , Análise de Sequência de DNA , Fumaça/efeitos adversosRESUMO
The action spectrum of photosynthesis of tomato was studied with excitation and fluorescence spectra of its leaf. To simulate action spectrum of tomato the fluorescent auxiliary was specially prepared and used to make the photo-ecology film. The film was used to cover the roof of greenhouses for planting tomatoes in Jianguo village of Xinfa town, Daoli district, Harbin. The survey of ecology conditions, tomato growth and yield has been made in comparison with those in the greenhouse using normal film. It is shown that the yield of tomato in the photo-ecology film greenhouse has increased by 53.7%, which leads to a production value rise of 61.4%.
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Ecologia/métodos , Fotossíntese/fisiologia , Solanum lycopersicum/fisiologia , Agricultura/métodos , Luz , Solanum lycopersicum/crescimento & desenvolvimentoRESUMO
The porphyrin compound in human body mainly includes hemoglobin, protoheme, protoporphyrin, coproporphyrin, uroporphyrin and so on. As we know, the metabolism of the porphyrin in human body depends on the physical conditions. It was found that the relative content of protoporphyrin (PPIX) and carotenoid in blood varied with the developing of the malignant tumor. A system, including Ti: sapphire laser, optical fiber delivery system, fluorescence probe, spectrometer CCD and computer, has been developed to examine the porphyrin in human superficial skin tissue without trauma. It was shown that the fluorescence spectrum of the porphyrin obtained from the superficial skin tissue of human earlobe has the same feature as that from the aqueous solution with PP IX.
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Biomarcadores Tumorais/sangue , Porfirinas/sangue , Pele/irrigação sanguínea , Carotenoides/sangue , Coproporfirinas/sangue , Humanos , Protoporfirinas/sangue , Pele/química , Espectrometria de Fluorescência , Uroporfirinas/sangueRESUMO
The aim of this study was to a conduct a systematic review of carmustine wafers (Gliadel wafers) for the treatment of glioblastoma multiforme (GBM) to assess the survival benefit and safety of this therapy. The inclusion criteria were 1) prospective or retrospective clinical trial; 2) patients who had undergone resection for primary GBM or first recurrence of GBM with or without carmustine wafer implantation; 3) patients with malignant gliomas that included GBM; 4) outcomes including survival analysis of the GBM population. Six trials met the inclusion criteria; four were randomized, controlled trials and two were retrospective. The trials varied with regard to the type of patients and interventions. In three of the trials, patients with GBM who received carmustine wafers had significantly longer median survival than patients who did not receive wafers. Implantation of carmustine wafers did not significantly improve progression-free survival. Carmustine wafers did not increase adverse effects. This systematic review suggests that carmustine wafers have demonstrated promise as an effective and tolerable treatment in comparison to other treatment strategies in patients with GBM.
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Antineoplásicos Alquilantes/efeitos adversos , Antineoplásicos Alquilantes/uso terapêutico , Carmustina/efeitos adversos , Carmustina/uso terapêutico , Glioblastoma/tratamento farmacológico , Antineoplásicos Alquilantes/administração & dosagem , Carmustina/administração & dosagem , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de SobrevidaRESUMO
Epidemiological studies have evaluated the association between apolipoprotein E (ApoE) gene polymorphism and multiple sclerosis (MS) risk. However, the results remain conflicting. Therefore, in order to derive a more precise association of ApoE gene polymorphism with MS risk, we performed this meta-analysis. Systematic searches of electronic databases PubMed, Embase and Web of Science, as well as hand searching of the references of identified articles were performed. Twenty studies were identified, covering a total of 4080 MS cases and 2897 controls. The results showed evidence for significant association between ApoE ε2 mutation and MS risk (for ε2/ε4 versus ε3/ε3: OR=1.74, 95% CI=1.12-2.71, p=0.01; for ε2 allele versus ε3 allele: OR=1.16, 95% CI=1.01-1.35, p=0.04). In the subgroup analysis by ethnicity, the similar results were obtained among Europeans (for ε2/ε4 versus ε3/ε3: OR=1.81, 95% CI=1.14-2.87, p=0.01; for ε2 allele versus ε3 allele: OR=1.19, 95% CI=1.02-1.38, p=0.03). After excluding the outlier studies by observing Galbraith plot, marginal association was found between ApoE ε3/ε4 genotype and the protective factor for MS (for ε3/ε4 versus ε3/ε3: OR=0.86, 95% CI=0.75-0.99, p=0.04). In summary, the present meta-analysis provides evidence that ApoE ε2 mutation is associated with MS risk. In addition, ApoE ε3/ε4 genotype appears to be a protective factor for MS.