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1.
J Cell Biochem ; 119(11): 9006-9016, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30015387

RESUMO

Isothiocyanates (ITCs) are natural chemoprotective products found abundantly in cruciferous vegetables. However, the cancer-relevant targets and molecular mechanisms of ITCs remain unclear. We hypothesize that ITCs, as electrophiles, can interact with the catalytic triads (CYS, HIS, and ASP) of the proteasomal cysteine deubiquitinases USP14 and UCHL5, ultimately inhibiting their activities. In the current study, we exploited this possibility by performing both computational docking and biochemical validation assays using human breast and prostate cancer cell models. Docking results suggest that benzyl isothiocyanate, phenethyl isothiocyanate, and DL-sulforaphane are more potent inhibitors of UCHL5 than USP14, and these ITCs could interact with the catalytic triads of UCHL5 and USP14. Indeed, ubiquitin vinyl sulfone assay confirmed the inhibitory activity of each ITC on the ubiquitin-binding activity of UCHL5 and USP14. We also found that inhibition of USP-14 and UCHL5 activities by the ITCs caused increased levels of USP14 and UCHL5 proteins, but not the third 19S-deubiquitinating enzyme (DUB), POH1/RPN11, suggesting feedback loop activation and further supporting that ITCs are inhibitors of proteasomal cysteine DUBs. Associated with DUB inhibition by ITCs, ubiquitinated proteins were significantly increased, accompanied with induction of apoptosis, inhibition of proliferation and suppression of cell invasion. Our findings of ITCs as proteasomal cysteine DUB inhibitors should provide insightful information for designing, discovering and developing potent, specific 19S-DUB inhibitors for cancer therapies.


Assuntos
Enzimas Desubiquitinantes/metabolismo , Isotiocianatos/farmacologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , Humanos , Masculino , Transativadores/metabolismo , Ubiquitina Tiolesterase/metabolismo
2.
J Med Virol ; 89(4): 653-659, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27591428

RESUMO

Hepatitis C Virus (HCV) promotes lipid droplet (LD) formation and perturbs the expression of the LD associated PAT proteins ADRP and TIP47, to promote its own lifecycle. HCV enhances TIP47 and suppresses ADRP by displacing it from LD surface in infected cell models. We have previously shown that suppression of TIP47 by miR-148a and miR-30a decreased intracellular LDs and HCV RNA. Thus, this study aimed at examining whether this microRNA-mediated suppression of HCV would limit HCV-dependent displacement of ADRP from LDs. ADRP expression was examined in 21 HCV-infected liver biopsies and 9 healthy donor liver tissues as well as in HCV-infected Huh7 cells using qRT-PCR. miR-148a and miR-30a expression was manipulated using specific oligos in JFH-1 infected, oleic acid treated cells, to study their impact on ADRP expression using qRT-PCR, and immunofluorescence microscopy. Intracellular HCV RNA was assessed using qRT-PCR. ADRP is down regulated in patients as well as HCVcc-JFH-I infected cell models. Forcing the expression of both miRNAs induced ADRP on the mRNA and protein levels. This study shows that HCV suppresses hepatic ADRP expression in infected patients and cell lines. Forcing the expression of miR-148a and miR-30a limits the suppressive effect of HCV on ADRP. J. Med. Virol. 89:653-659, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Hepacivirus/patogenicidade , Interações Hospedeiro-Patógeno , MicroRNAs/metabolismo , Perilipina-2/antagonistas & inibidores , Adulto , Biópsia , Linhagem Celular , Feminino , Perfilação da Expressão Gênica , Hepatite C/patologia , Hepatócitos/virologia , Humanos , Fígado/patologia , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Perilipina-3/metabolismo , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real
3.
Saudi Dent J ; 36(6): 947-953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38883903

RESUMO

This in vitro study aimed to evaluate the additive manufacturing (AM) of cobalt chromium Co-Cr and titanium Ti alloy clasps for clinical use. After scanning the Ni-Cr die of the first molar, Akers' clasps were designed using computer-aided design/ computer-aided manufacturing (CAD/CAM). The clasps were manufactured from Co-Cr-W dental alloy and Ti-6Al-4V alloy powder using AM machines. Then, they were divided into two groups. The initial retentive force of the clasps was measured using a universal testing machine. Cyclic loading of the clasps was carried out by a specially designed insertion-removal testing apparatus in wet condition up to 5000 cycles. Retentive force was measured at 1000, 2000, 3000, 4000, and 5000 cycles. Moreover, the intaglio surface of each clasp was scanned using the scanner; and superimposition between the pre- and post-cycling clasp files was performed to evaluate deformation after cyclic loading. The fitting surfaces of retentive clasp tips were examined with a scanning electron microscope (SEM). Finally, it has been found that the initial retentive force for the Co-Cr group was 10.81 ± 0.37 N, and for the Ti group was 5.41 ± 0.18 N. Additionally, during the testing periods, both Co-Cr and Ti clasps continued to lose retentive force within the cycles of placement and removal. This effect was more prominent in the Co-Cr than in the Ti clasps. The distances between pre- and post-cycling in the retentive arm were -0.290 ± 0.11 mm and -0.004 ± 0.01 mm in Co-Cr and Ti alloys, respectively, and in the reciprocal arm were -0.072 ± 0.04 mm and -0.032 ± 0.04 mm in Co-Cr and Ti alloys, respectively. The retentive force required to remove the Ti clasps was found to be significantly lower than those required to dislodge the Co-Cr clasps. Co-Cr and Ti clasps lost significant amounts of retentive force from the initial use to the 3.5-year periods of simulated clinical use.

4.
Neuroimage ; 59(2): 1315-23, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-21889995

RESUMO

Brain morphometric studies often incorporate comparative hemispheric asymmetry analyses of segmented brain structures. In this work, we present evidence that common user guided structural segmentation techniques exhibit strong left-right asymmetric biases and thus fundamentally influence any left-right asymmetry analyses. In this study, MRI scans from ten pediatric subjects were employed for studying segmentations of amygdala, globus pallidus, putamen, caudate, and lateral ventricle. Additionally, two pediatric and three adult scans were used for studying hippocampus segmentation. Segmentations of the sub-cortical structures were performed by skilled raters using standard manual and semi-automated methods. The left-right mirrored versions of each image were included in the data and segmented in a random order to assess potential left-right asymmetric bias. Using shape analysis we further assessed whether the asymmetric bias is consistent across subjects and raters with the focus on the hippocampus. The user guided segmentation techniques on the sub-cortical structures exhibited left-right asymmetric volume bias with the hippocampus displaying the most significant asymmetry values (p<<0.01). The hippocampal shape analysis revealed the bias to be strongest on the lateral side of the body and medial side of the head and tail. The origin of this asymmetric bias is considered to be based in laterality of visual perception; therefore segmentations with any degree of user interaction contain an asymmetric bias. The aim of our study is to raise awareness in the neuroimaging community regarding the presence of the asymmetric bias and its influence on any left-right hemispheric analyses. We also recommend reexamining previous research results in the light of this new finding.


Assuntos
Algoritmos , Artefatos , Transtorno Autístico/patologia , Encéfalo/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Pré-Escolar , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Polymers (Basel) ; 14(2)2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35054708

RESUMO

The wear of acrylic denture teeth is a serious problem that can change the vertical dimensions of dentures. This study evaluates the effect of adding salinized nano ZrO2 particles on the microstructure, hardness, and wear resistance of acrylic denture teeth. Heat polymerizing polymethyl methacrylate resin was mixed with salinized ZrO2 at concentrations of 5 wt.% and 10 wt.%. Acrylic resin specimens without filler addition were used as a control group. SEM/EDS analyses were performed and the Vickers' hardness was evaluated. Two-body wear testing was performed using a chewing simulator with a human enamel antagonist. After subjecting the samples to 37,500 cycles, both height loss and weight loss were used to evaluate the wear behavior. The microstructural investigation of the reinforced-denture teeth indicates sound nanocomposite preparation using the applied regime without porosity or macro defects. The addition of zirconium oxide nanofillers to PMMA at both 5% and 10% increased the microhardness, with values of up to 49.7 HV. The wear mechanism in the acrylic base material without nanoparticle addition was found to be fatigue wear; a high density of microcracks were found. The addition of 5 wt.% ZrO2 improved the wear resistance. Increasing the nanoparticles to 10 wt.% ZrO2 further improved the wear resistance, with no microcracks found.

6.
Medicine (Baltimore) ; 101(25): e29287, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35758358

RESUMO

ABSTRACT: Syncope is a temporary loss of consciousness usually related to insufficient blood flow to the brain. It's also called fainting or "passing out." Syncope is responsible for 3% to 5% of emergency department visits, with a hospitalization rate in about 40% of cases, with an average stay of 5.5 days. The Canadian Syncope Risk Score showed good discrimination and calibration for 30-day risk of serious adverse events after disposition from the emergency department.The aim was to assess Canadian Syncope Risk Score in predicting outcomes and mortality at the emergency department of Suez Canal University Hospitals.A prospective observational cohort study was carried out in emergency department in Suez Canal University Hospital. After approval by the Ethical and Research Committee of Faculty of Medicine, Suez Canal University, 60 patients with syncope attending to emergency department were included to this study. All included participants were assessed by history taking and they also assessed by the Canadian Syncope Risk Score.The Canadian Syncope Risk Score's mean of the study group was 4.9 and the range of the scores was from -2 to 11. The mean of the percentage of risk of serious events at 30 days in the study group was 29.17% and it ranged from 0.7% to 83.6%.There was a statistically significant difference between means Canadian Syncope Risk Score's score regarding complication occurrence. Cases which showed complications had a mean score of 7.33 compared to a mean score of 1.25 in case of no complication occurrence P-value <.001. At a cut-off point of more than 3 for the Canadian Syncope Risk Score's, sensitivity of that score in complication's occurrence prediction was 100% and the specificity was 87.5% P-value <.001.The Canadian Syncope Risk Score's is strong predictor for risk of serious adverse events and a good indicator for admission, with 100% sensitivity and 87.5% specificity at cut off point more than 3.


Assuntos
Serviço Hospitalar de Emergência , Síncope , Canadá/epidemiologia , Humanos , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Síncope/diagnóstico , Síncope/epidemiologia , Síncope/etiologia
7.
J Genet Eng Biotechnol ; 19(1): 15, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33474680

RESUMO

BACKGROUND: Detecting the genetic and physiological variations in two Japanese quail strains could be used to suggest a new avian model for future breeding studies. Consequently, two estimations were performed on two Japanese quail strains: gray quail strain (GJQS) and white jumbo quail strain (WJQS). The first estimation was conducted on carcass characteristics, breast muscles, breast concentration of collagen type I, and body measurements. In contrast, blood samples were collected for the second estimation for genomic DNA extraction and genetic analysis. RESULTS: A total of 62 alleles out of 97 specific alleles (63.92%) were detected overall loci (14 microsatellite loci) for the two strains. A total of 27 specific alleles of WJQS were observed, and 35 were obtained for GJQS. The percentage of similarity was 48.09% ranged from 4.35 with UBC001 to 100% with GUJ0051. WJQS had greater body weights and a higher value of pectoral muscle and supracoracoideus muscle than GJQS. The breast muscles of GJQS exhibited a higher concentration of type I collagen than the WJQS. Furthermore, males showed higher concentrations of collagen type I than females. WJQS showed a higher body length, chest girth, chest length, thigh length, thigh girth, drumstick length, and drumstick girth (cm) than GJQS. WJQS showed more significant differences in carcass traits compared with GJQS. CONCLUSION: The physiological differences between WJQS and GJQS were ascertained with microsatellite markers, which indicated high polymorphism between these strains. These observations provided a scientific basis for evaluating and utilizing the genetic resources of WJQS and GJQS in a future genetic improvement program.

8.
Surg Infect (Larchmt) ; 21(8): 709-715, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32096688

RESUMO

Background: Descending necrotizing mediastinitis [DNM] is a serious complication of odontogenic infections, being associated with a high mortality rate. The diagnosis, classification, and management depend on computed tomography [CT] findings. Incision, drainage, and debridement represent the principal management. This study aimed to assess the prognosis in odontogenic DNM. Methods: The DNM type I was managed by transcervical mediastinal drainage, while in DNM type II, a right or left posterolateral thoracotomy was used. Data were compared among survivors and deceased to detect the risk factors affecting the prognosis. Results: This study included 63 patients. Transcervical mediastinal drainage was performed in 57 patients with Endo Type I while drainage through a right posterolateral thoracotomy was performed in the other five patients with Endo Type I and one patient with Endo Type IIA. Of patients in the study, 82.5% survived while 17.5% died because of multiple organ failure. Multiple complications and severe sepsis or septic shock as risk factors were statistically significant. Conclusion: A CT scan is the modality of choice for diagnosis and classification of DNM. Incision and drainage of the maxillofacial infection with mediastinal drainage and debridement represent the main management. Multiple complications and severe sepsis or septic shock were associated with poor prognosis.


Assuntos
Infecção Focal Dentária/complicações , Mediastinite/etiologia , Mediastinite/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Egito , Feminino , Humanos , Estudos Longitudinais , Masculino , Mediastinite/classificação , Mediastinite/diagnóstico , Pessoa de Meia-Idade , Necrose , Estudos Retrospectivos , Fatores Socioeconômicos , Adulto Jovem
9.
Immunol Lett ; 169: 52-60, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26518141

RESUMO

BACKGROUND AND AIM: Natural killer cells are part of the innate immunity involved in viral eradication and were shown to be greatly affected by HCV infection. Epigenetic regulation of NK cell function by microRNAs was not efficiently studied before and was never studied in HCV infection; therefore the aim of this study was to assess for the first time the role of microRNAs in regulating the function of NK cells of HCV-infected patients and hence viral replication in the target HCV-infected Huh7 cells. METHODOLOGY: NK cells were isolated from PBMCs of HCV-infected patients as well as controls, and HCV-infected liver biopsies as well as Huh7 cells infected with the virus were used. For the infection of Huh7 cells, first viral vector was in-vitro transcribed into viral RNA that was then used to infect naїve Huh7 cells. Supernatant from the infected cells was then collected and used for further infection. For manipulation of NK cells or Huh7 cells, miR-182 mimics and inhibitors were transfected via lipofection method. RNA was extracted from each cell population, reverse transcribed. Gene expression as well as viral load was quantified using qPCR. RESULTS: Screening of NKG2A and NKG2D between patients and controls showed no difference in expression of NKG2A, while NKG2D was found to be downregulated. In view of that, bioinformatics analysis was performed and showed that miR-182 has potential binding sites on both the inhibitory receptor NKG2A and the activating receptor NKG2D, and on its ligand ULBP2, as well as on the viral genome itself. In NK cells of HCV-infected patients, miR-182 was found to be over-expressed compared to controls; its ectopic expression was found to decrease NKG2D mRNA level, while miR-182 inhibitors were able to decrease NKG2A mRNA compared to untransfected cells. In addition, co-culturing genotype 4 or 2 HCV-infected Huh7 cells with miR-182 mimicked NK cells of HCV-infected patients showed decreased viral replication, suggesting an enhanced NK cell function. On the other hand, miR-182 and ULBP2 were both found to be downregulated in HCV liver tissues and HCV-infected Huh7 cells compared to their controls. miR-182 mimics were found to decrease ULBP2 mRNA and increase viral replication in genotypes 4 and 2 HCV-infected target (Huh7) cells compared to controls, while miR-182 inhibitor decreased viral replication in the cell models. CONCLUSION: miR-182 was never investigated before, neither in HCV infection nor in NK cells, and we found it to have dysregulated expression in both liver tissues and NK cells of HCV-infected patients compared to control. In addition to that, miR-182 was found to have a contradicting effect in both effector cell and its HCV-infected target cell regarding HCV replication.


Assuntos
Hepacivirus/fisiologia , Hepatite C/imunologia , Hepatócitos/fisiologia , Células Matadoras Naturais/fisiologia , MicroRNAs/metabolismo , Linhagem Celular , Epigênese Genética , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Regulação da Expressão Gênica , Hepatite C/genética , Hepatócitos/virologia , Especificidade de Hospedeiro , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células Matadoras Naturais/virologia , Ativação Linfocitária , MicroRNAs/genética , Subfamília C de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Especificidade de Órgãos , Carga Viral , Replicação Viral
10.
J Infect ; 70(1): 78-87, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25218426

RESUMO

OBJECTIVE: The tetraspanin CD81 is one of the main receptors involved in hepatitis C virus entry. Herein, we aimed to explore the role of microRNAs in regulating CD81 receptor expression and function. PATIENTS AND METHODS: Bioinformatics analysis was carried out to select potential mircroRNAs that binds CD81 3'untranslated region. Liver biopsies taken from 28 HCV genotype- 4 patients and 10 healthy donors were screened. Naïve, JFH1 and ED43/JFH1- infected- Huh7 cells were transfected with mimics and inhibitors followed by analyzing CD81 protein and mRNA expression. This was done using flow cytometry and Q-RT PCR, respectively. HCV entry into Huh7 cells was investigated post-transfection. Binding confirmation was done using luciferase reporter vector harboring wild/mutant target sites of microRNA. The impact of Epigallocatechin-gallate on modulating microRNA/CD81 expression was assessed. RESULTS: Bioinformatics revealed that CD81 is a potential down-stream target for miR-194. A significant inverse correlation was found between miR-194 and CD81 expression in liver biopsies of HCV patients. Forcing the expression of miR-194 showed a down-regulation of CD81 protein, mRNA expression and significantly abrogated the HCV infectivity of Huh7 cells. Stimulation with EGCG enhanced mir-194 expression and down-regulated CD81 expression. CONCLUSION: This study showed that mir-194 hinders HCV entry through targeting CD81 receptors.


Assuntos
Hepacivirus/metabolismo , MicroRNAs/metabolismo , Tetraspanina 28/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Biologia Computacional , Citometria de Fluxo , Hepacivirus/genética , Hepatite C , Humanos , Fígado/patologia , Transplante de Fígado , MicroRNAs/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
11.
FEBS Lett ; 589(17): 2266-73, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26170028

RESUMO

This study aimed at identifying potential microRNAs that modulate hepatic lipid droplets (LD) through targeting the Tail interacting protein of 47 kDa (TIP47) in HCV infection. Bioinformatics analysis revealed that miR-148a and miR-30a potentially target TIP47. Expression profiling showed that both microRNAs were downregulated, while TIP47 was upregulated in liver biopsies of HCV-infected patients. Forcing the expression of both microRNAs in JFH-I infected, oleic acid-treated Huh7 cells, significantly suppressed TIP47 expression and reduced cellular LDs with marked decrease in viral RNA. This study shows that miR-148a and miR-30a, regulate TIP47 expression and LDs in HCV infected cells.


Assuntos
Hepacivirus/genética , Gotículas Lipídicas/metabolismo , MicroRNAs/genética , Proteínas de Transporte Vesicular/genética , Regiões 3' não Traduzidas/genética , Adulto , Idoso , Sequência de Bases , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Hepacivirus/fisiologia , Interações Hospedeiro-Patógeno/genética , Humanos , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Perilipina-3 , Interferência de RNA , RNA Viral/genética , RNA Viral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Proteínas de Transporte Vesicular/metabolismo
12.
J AAPOS ; 19(3): 286-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25900770

RESUMO

Of 170 children who underwent 248 glaucoma procedures at a single center between 2005 and 2012, 13 eyes of 12 children (5.24%) developed decompression retinopathy, which resolved spontaneously, leaving no visible structural damage to the fundus structures. The mean age of children with hemorrhages was 39.2 ± 63.5 months; of those without, 8.0 ± 9.7 months. The fundus hemorrhages were peripapillary, subfoveal, dot-and-blot, and diffuse. Combined angle and filtering surgery with antimetabolite was the most common procedure performed in all eyes. There were no statistically significant differences between eyes with and without hemorrhages with respect to demographics or preoperative and operative characteristics. No definite ocular risk factor was identified for the occurrence of decompression retinopathy.


Assuntos
Descompressão , Cirurgia Filtrante , Glaucoma/cirurgia , Complicações Pós-Operatórias , Hemorragia Retiniana/etiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Pressão Intraocular , Masculino
13.
J Endod ; 30(5): 321-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15107643

RESUMO

Information concerning the anatomy of the physiological foramen is limited. The aim of this study was to investigate the distance between the physiological and anatomical apex, accessory foramina frequency, and the shape and diameter of the physiological foramen in maxillary and mandibular molars. The apical anatomy of 523 maxillary and 574 mandibular molars from an Egyptian population was investigated by means of a computer-aided stereomicroscope (40 x magnification). The following results were obtained:


Assuntos
Cavidade Pulpar/anatomia & histologia , Dente Molar/anatomia & histologia , Ápice Dentário/anatomia & histologia , Egito , Humanos , Imageamento Tridimensional , Mandíbula , Maxila , Microscopia/métodos
14.
Int J Dent ; 2012: 343712, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22666251

RESUMO

Objective. Comparing effect of different restoration techniques on fracture resistance of compromised roots. Methods. Crowns of 100 single-rooted teeth were sectioned and 10 roots were kept as negative control group (Group 1). Remaining roots were instrumented and divided into one and positive control group of 10 samples (Group 2) and 4 experimental groups of 20 samples each. Group 3: roots were obturated with gutta-percha; Group 4: roots were restored with gutta-percha, composite, and glass fiber post; Group 5: roots were obturated with Resilon; Group 6: Roots were restored with Resilon, composite, and glass fiber post. Roots were weakened before obturation in groups 2, 3, and 5 and after obturation in groups 4 and 6. Fracture strengths were measured using Dartec testing machine and fracture load was recorded in kilo-Newton. Statistical analysis was done using ANOVA and Tukeys test. Results. The fractures resistance of restored roots was significantly higher in groups 4, 5, and 6 than in Groups 2 and 3. There were no significant differences between groups 1, 4, 5, and 6. Conclusions. Restoration of weakened roots with Resilon or bonding an intermediate composite resin to coronal radicular dentin and to glass fiber post increased their fracture resistance.

15.
Int Arch Med ; 2(1): 7, 2009 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-19327152

RESUMO

INTRODUCTION: Almost 30% of patients with pancreatic cancer have locally advanced tumours in absence of distant metastasis. Surgical resection is often contraindicated. The combination of gemcitabine with concurrent radiation therapy is a promising new approach that is being investigated for treating patients' unresectable pancreatic cancer. This work aims at assessing the efficacy of preoperative gemcitabine based chemo-radiotherapy in increasing the resectability rate for patients' locally advanced pancreatic cancer. PATIENTS AND METHODS: From March 2006 to November 2007, 25 patients with locally advanced non metastatic pancreatic cancer were treated by preoperative gemcitabine based chemo-radiotherapy. The radiation dose was 54 Gray in 30 fractions over 6 weeks prescribed to the isocenter. Gemcitabine (300 mg/m2) was given through a 30 minute intravenous infusion. This was done 30 minutes before the radiation sitting on a weekly basis throughout the radiotherapy course.Approximately 6 weeks after the completion of chemo radiation, an evaluation was performed regarding tumour response and resectability as well as acute toxicity. Pancreaticoduodenectomy was performed for operable patients with surgical reconstruction. RESULTS: Patients who achieved complete resection (CR) numbered 2 (8%), while those achieving partial resection (PR) totalled 11 (44%); six of these patients were considered ro be operable. Thus Pancreaticoduodenectomy was performed on 8 patients (2 with CR and 6 with PR) with surgical reconstruction. Patients who had a stable disease numbered 4 (16%), and those with progressive diseases included a group of eight (32%). The postoperative 30 day mortality occurred only in one patient (12.5%). Acute toxicity of chemoradiation occurred in the form of grade I leucopoenia and thrombocytopenia. Hepatic toxicity, nausea, and vomiting were found in 8 patients (32%), 10 patients (40%) and 4 patients (16%), respectively. The postoperative 30 day mortality occurred only in 1 patient. Also, minor biliary leakage and leakage from gastrointestinal anaestomosis both occurred in a single patient. Out of the 8 patients who underwent radical surgical resection, only one developed local recurrence and simultaneous liver metastasis during the follow up period. The median survival of all patients was 12 months. CONCLUSION: Preoperative gemcitabine based chemoradiation might benefit patients with locally advanced non metastatic pancreatic cancer by increasing the resectability without significant acute toxicity.

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