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1.
Braz. J. Pharm. Sci. (Online) ; 59: e21233, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1429964

RESUMO

Abstract Telomerase enzyme is necessary for the elongation of telomeres while telomerase being critical for aging and cancer. Metformin, ibuprofen, and acetylsalicylic acid used in this research are drugs that millions of people already use and that many are likely to use in future. In this study, the effects of these drugs on telomerase activity of Mus musculus swiss albino mice in liver tissue were investigated and the telomerase activity was measured with a PCR-ELISA based kit. In the study a possible connection between telomerase enzyme activity and activities of antioxidant enzymes was also investigated by determining the activity of superoxide dismutase (SOD) and catalase enzymes. The data obtained show that metformin slightly decreased telomerase enzyme activity in low dose application; however, this change was not statistically significant. In ibuprofen application, there was a significant inhibitory effect when high doses were used; whereas, there was a slight inhibitory effect at low doses. In acetylsalicylic acid application, a slight activator effect was detected; it was not statistically significant, though. Metformin was observed to increase catalase and SOD activities in general while low and high doses of acetyl salicylic acid showed different effects. In addition, ibuprofen caused a statistically significant increase in liver SOD values. It is important to note that this study demonstrated a significant inhibitory effect of ibuprofen on telomerase enzyme activity in animal models..


Assuntos
Animais , Masculino , Feminino , Camundongos , Aspirina/efeitos adversos , Ibuprofeno/efeitos adversos , Telomerase/análise , Metformina/efeitos adversos , Catalase
2.
Clin Exp Dent Res ; 8(6): 1315-1321, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36069295

RESUMO

OBJECTIVE: To compare the surface roughness of sandblasted, large grit, acid-etched (SLA) surfaced titanium discs, after implantoplasty (IP) with different combinations of rotating instruments without or with the subsequent use of a silicone polisher. METHODS: Titanium discs (n = 12 per group) with an SLA surface were treated with the following IP protocols: (1) Tungsten carbide bur sequence from company 1 (Komet Dental) without or with polishing (P) with a silicone polisher (Brownie®), (2) tungsten carbide bur sequence from company 2 (Hager & Meisinger GmbH) without or with P, and (3) diamond bur sequence (125, 40, 15-µm grit) without or with P. Pristine turned (T) and SLA titanium discs were used as negative and positive controls, respectively. Surface roughness measurements were taken with a contact profilometer rendering Ra and Rz values. RESULTS: All IP protocols, even without P, resulted in significantly reduced surface roughness compared to the SLA group. The tungsten carbide bur protocols, even without P, resulted in a surface roughness similar to or significantly lower than that in the T group in terms of Ra and Rz , respectively. IP with the diamond bur sequence resulted in a significantly rougher surface compared to that achieved with the carbide burs. In all IP groups, P with a silicone polisher resulted in a significantly smoother surface. CONCLUSIONS: IP with dedicated tungsten carbide burs without or with the subsequent use of a silicone polisher resulted in a surface roughness similar to or significantly lower than that of commercially available turned surfaces. IP with a diamond bur sequence required additional polishing to achieve a comparable surface roughness to that of commercially available turned surfaces.


Assuntos
Implantes Dentários , Polimento Dentário , Polimento Dentário/métodos , Titânio , Propriedades de Superfície , Diamante , Silicones
3.
Heliyon ; 8(4): e09311, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35520623

RESUMO

Purpose: This study aims to evaluate the potential of machine learning algorithms built with radiomics features from computed tomography urography (CTU) images that classify RB1 gene mutation status in bladder cancer. Method: The study enrolled CTU images of 18 patients with and 54 without RB1 mutation from a public database. Image and data preprocessing were performed after data augmentation. Feature selection steps were consisted of filter and wrapper methods. Pearson's correlation analysis was the filter, and a wrapper-based sequential feature selection algorithm was the wrapper. Models with XGBoost, Random Forest (RF), and k-Nearest Neighbors (kNN) algorithms were developed. Performance metrics of the models were calculated. Models' performances were compared by using Friedman's test. Results: 8 features were selected from 851 total extracted features. Accuracy, sensitivity, specificity, precision, recall, F1 measure and AUC were 84%, 80%, 88%, 86%, 80%, 0.83 and 0.84, for XGBoost; 72%, 80%, 65%, 67%, 80%, 0.73 and 0.72 for RF; 66%, 53%, 76%, 67%, 53%, 0.60 and 0.65 for kNN, respectively. XGBoost model had outperformed kNN model in Friedman's test (p = 0.006). Conclusions: Machine learning algorithms with radiomics features from CTU images show promising results in classifying bladder cancer by RB1 mutation status non-invasively.

4.
J Comput Assist Tomogr ; 45(5): 782-787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34176881

RESUMO

OBJECTIVE: The aim of the study was to evaluate the interobserver agreement and diagnostic accuracy of COVID-19 Reporting and Data System (CO-RADS), in patients suspected COVID-19 pneumonia. METHODS: Two hundred nine nonenhanced chest computed tomography images of patients with clinically suspected COVID-19 pneumonia were included. The images were evaluated by 2 groups of observers, consisting of 2 residents-radiologists, using CO-RADS. Reverse transcriptase-polymerase chain reaction (PCR) was used as a reference standard for diagnosis in this study. Sensitivity, specificity, area under receiver operating characteristic curve (AUC), and intraobserver/interobserver agreement were calculated. RESULTS: COVID-19 Reporting and Data System was able to distinguish patients with positive PCR results from those with negative PCR results with AUC of 0.796 in the group of residents and AUC of 0.810 in the group of radiologists. There was moderate interobserver agreement between residents and radiologist with κ values of 0.54 and 0.57. CONCLUSIONS: The diagnostic performance of CO-RADS for predicting COVID-19 pneumonia showed moderate interobserver agreement between residents and radiologists.


Assuntos
COVID-19/diagnóstico por imagem , Internato e Residência/estatística & dados numéricos , Radiologistas/estatística & dados numéricos , Sistemas de Informação em Radiologia/normas , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , SARS-CoV-2 , Sensibilidade e Especificidade
5.
J Back Musculoskelet Rehabil ; 30(5): 1061-1067, 2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-28505960

RESUMO

BACKGROUND: Lumbar lordosis is required for bipedalism. OBJECTIVES: To investigate age-related changes in lumbar lordosis and to clarify the relationships between lumbar lordosis and vertebral wedging and disc degeneration. METHODS: A total of 300 women were included in this retrospective study, 50 in each of six age groups (20-, 30-, 40-, 50-, 60- and 70-year-olds). Patients with vertebral collapse, instable fracture or disc sequestration were excluded. In each patient, lumbar lordosis angle, posterior vertebral wedging, L5-S1 intervertebral disc angle, L5/L1 vertebral height ratio and L5-S1 intervertebral disc/L1-L2 intervertebral disc height ratio were examined. Significance level was set at p< 0.05 and two-sided tests were used. RESULTS: Significant differences were found in lumbar lordosis according to age group (p< 0.001). Lumbar lordosis correlated most strongly with L4 posterior vertebral wedging, L5 posterior vertebral wedging and L5-S1 intervertebral disc angle, in that order (r= 0.50, r= 0.40, r= 0.32, respectively; p< 0.001). CONCLUSION: In this cohort, strong spinal structure was maintained during physiological aging from 20 to 40 years of age; lumbar lordosis increased by 50 years of age. Increased lordosis correlated with increased posterior vertebral wedging and loss of posterior disc height.


Assuntos
Envelhecimento/fisiologia , Lordose/fisiopatologia , Vértebras Lombares/fisiologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/fisiologia , Lordose/diagnóstico , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos
6.
J Clin Ultrasound ; 45(6): 332-336, 2017 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-28186621

RESUMO

PURPOSE: To investigate the relationship among great saphenous vein (GSV) anatomic type, segmental aplasia, and reflux. METHODS: Color Doppler ultrasonography (CDUS) was performed on 475 legs of 277 consecutive patients with venous symptoms between November 2015 and August 2016. Exclusion criteria were previous venous surgery and venous thrombosis. Five GSV types were identified based on the saphenous compartment at thigh level, and segment aplasia and reflux were investigated. RESULTS: The most frequent GSV type was type A, ie, a single GSV extending within the saphenous compartment with no accompanying large parallel tributary (53%), and the least frequent type was type B, GSV duplication (1.3%). Patients with and without reflux showed similar distributions of GSV type (p = 0.389). Segmental aplasia was observed in 117 (24.63%) of 475 legs. The mean age of patients with GSV reflux was compared between patients with and without aplasia (p = 0.798). CONCLUSIONS: The frequency of venous reflux was nearly identical across GSV types. The frequency of segmental aplasia was similar in patients with and without reflux. Despite these similarities, defining GSV type and identifying segmental aplasia can provide guidance for treatment. In particular, type D GSVs, defined by the presence of an anterior accessory branch, should be investigated when performing CDUS. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:332-336, 2017.


Assuntos
Veia Safena/anatomia & histologia , Ultrassonografia Doppler em Cores/métodos , Varizes/diagnóstico por imagem , Insuficiência Venosa/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Veia Safena/diagnóstico por imagem
7.
Springerplus ; 5(1): 1500, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652073

RESUMO

PURPOSE: The medial patellofemoral ligament (MPFLL)/lateral patellar retinaculum (LPR) ratio were assessed in knees as a means to detect patellar malalignment. We also aimed to evaluate the prevalence of the various types of trochlear dysplasia in patients with patellar malalignment. MATERIALS AND METHODS: After approval of our institutional ethics committee, we conducted a retrospective study that included 450 consecutive patients to evaluate them for the presence of patellar malalignment. Parameters investigated were the trochlear type, sulcus angle, presence of a supratrochlear spur, MPFLL, LPR, patella alta, and patella baja by means of 1.5T magnetic resonance imaging (MRI). Overall, 133 patients were excluded because of the presence of major trauma, multiple ligament injuries, bipartite patella, and/or previous knee surgery. The Dejour classification was used to assess trochlear dysplasia. Two experienced radiologists (HKY, EEE) evaluated the images. Their concordance was assessed using the kappa (κ) test. RESULTS: The frequencies of patellar malalignment and trochlear dysplasia were 34.7 and 63.7 %, respectively. The frequency of trochlear dysplasia associated with patellar malalignment was 97.2 %. An MPFLL/LPR ratio of 1.033-1.041 had high sensitivity and specificity for malalignment. The researchers' concordance was good (κ = 0.89, SE = 0.034, P < 0.001). CONCLUSION: Trochlear dysplasia is frequently associated with patellar malalignment. An increased MPFLL/LPR ratio is useful for detecting patellar malalignment on knee MRI, which is a novel quantitative method based on ligament length.

8.
Diagn Interv Radiol ; 22(3): 273-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27035591

RESUMO

PURPOSE: We aimed to investigate the prevalence of lumbar multifidus muscle (LMM) atrophy in patients having mechanical low back pain with and without disc hernia. METHODS: In total, 2028 lumbar magnetic resonance imaging scans of low back pain patients (age range, 18-88 years) were re-evaluated retrospectively. LMM atrophy was visually assessed in axial sections of L4-L5 and L5-S1 levels. RESULTS: LMM atrophy prevalence at both levels was significantly higher in subjects ≥40 years compared with younger adults (P < 0.001). LMM atrophy was significantly more frequent in women than in men (P < 0.001). Among patients with low back pain without hernia, LMM atrophy was significantly more frequent than normal muscle (n=559 vs. n=392; P < 0.001). Frequency of LMM atrophy in low back pain patients without disc hernia was 13%. Hernia was more frequent in patients with LMM atrophy compared with patients without atrophy (P < 0.001). CONCLUSION: LMM atrophy is more common in women; its prevalence and severity are observed to increase with advancing age, and disc hernia is found more frequently in individuals with LMM atrophy.


Assuntos
Deslocamento do Disco Intervertebral/diagnóstico por imagem , Dor Lombar/diagnóstico por imagem , Atrofia Muscular/diagnóstico por imagem , Músculos Paraespinais/diagnóstico por imagem , Adulto , Fatores Etários , Feminino , Humanos , Dor Lombar/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/etiologia , Músculos Paraespinais/patologia , Prevalência , Estudos Retrospectivos , Fatores Sexuais
9.
Indian J Radiol Imaging ; 26(4): 455-459, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28104937

RESUMO

BACKGROUND: Trochlear dysplasia is the most commonly encountered congenital etiologic factor of anterior knee pain. AIMS: The purpose of this study was to evaluate the relationship between trochlear dysplasia with medial patellar plica as well as to investigate the distribution of plica types according to types of dysplasia. SETTINGS AND DESIGN: This is a retrospective case-control study. MATERIALS AND METHODS: This study was conducted among 138 knee magnetic resonance imaging (MRI) scans. The presence of medial plica and its types were compared among 69 patients in whom trochlear dysplasia had been detected and 69 individuals with normal trochlear who were of the same age and gender as the patient group. STATISTICAL ANALYSIS: Trochlear dysplasia and medial plica was compared by Chi-square with Yates correction and Fisher's exact probability tests (P < 0.001). The data were presented as mean, standard deviation, minimum-maximum, frequency, and percentage. RESULTS: Of all the patients (n = 138), the number of patients in whom plica was observed was n = 104 (75.3%), and the distribution of plica type was as follows: n = 70 (67.3%) Type 1, n = 25 (24%) Type 2, and n = 9 (8.6%) Type 3. Medial plica was more frequently observed in patients with trochlear dysplasia (P < 0.001). Type 2 and Type 3 medial plica were more frequently encountered in trochlear dysplasia (P < 0.001). Type 3 plica was not seen in patients with normal trochlea. CONCLUSION: Medial patellar plica is more frequently seen in trochlear dysplasia. As the type of trochlear dysplasia progresses, the prevalence of thicker and shelf-shaped plica increases.

10.
Med Princ Pract ; 13(1): 51-3, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14657621

RESUMO

OBJECTIVE: Systemic lupus erythematosus (SLE) with leptomeningeal involvement is a rare condition. We report a case in a 17-year-old woman. CLINICAL PRESENTATION AND INTERVENTION: The patient was admitted to hospital with the complaints of vertigo, nausea, vomiting, headache, diplopia, ptosis on the left and weakness of the left leg. A diagnosis of SLE was established, with diffuse leptomeningeal involvement demonstrated by cranial magnetic resonance imaging. When treated with steroids, the clinical problems resolved almost completely. CONCLUSIONS: Although rare, leptomeningeal involvement can complicate SLE. Cranial magnetic imaging can demonstrate tissue involvement. The condition responds to steroid therapy.


Assuntos
Cistos Aracnóideos/diagnóstico , Lúpus Eritematoso Sistêmico/diagnóstico , Adolescente , Cistos Aracnóideos/complicações , Cistos Aracnóideos/diagnóstico por imagem , Cistos Aracnóideos/tratamento farmacológico , Dexametasona/uso terapêutico , Diagnóstico Diferencial , Feminino , Glucocorticoides/uso terapêutico , Cefaleia/complicações , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/fisiopatologia , Imageamento por Ressonância Magnética , Radiografia
11.
Int J Neurosci ; 113(7): 915-22, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12881184

RESUMO

Pathogenesis of leukoaraiosis (LA) is not clearly understood and its significance in patients with stroke remains undetermined. In the Neurology Department of Ankara Hospital, computed tomography (CT) examination of brain was performed for various reasons in 288 patients. LA was detected in 178 patients by the use of brain CT. Patients with LA had a higher incidence of hypertension history (70.8%) when compared with the non-LA group (57.3%; p <.05). There was no statistically significant difference in terms of sex, mean age, smoking, diabetes mellitus, history of cerebrovascular disease, cardiac failure, ischemic cardiac disease between patients with and without LA. We showed that LA is related to hypertension but not related to age, diabetes mellitus, or cardiac disease in our patient population.


Assuntos
Transtornos Cerebrovasculares/epidemiologia , Doenças Desmielinizantes/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Encéfalo/diagnóstico por imagem , Transtornos Cerebrovasculares/diagnóstico , Comorbidade , Doenças Desmielinizantes/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Tomografia Computadorizada por Raios X
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