Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 90
Filtrar
1.
Front Oncol ; 13: 1292635, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074643

RESUMO

Introduction: Many well-known risk factors for breast cancer are associated with dysbiosis (an aberrant microbiome). However, how bacterial products modulate cancer are poorly understood. In this study, we investigated the effect of an exopolysaccharide (EPS) produced by the commensal bacterium Bacillus subtilis on breast cancer phenotypes. Although B. subtilis is commonly included in probiotic preparations and its EPS protects against inflammatory diseases, it was virtually unknown whether B. subtilis-derived EPS affects cancer. Methods: This work investigated effects of EPS on phenotypes of breast cancer cells as a cancer model. The phenotypes included proliferation, mammosphere formation, cell migration, and tumor growth in two immune compromised mouse models. RNA sequencing was performed on RNA from four breast cancer cells treated with PBS or EPS. IKKß or STAT1 signaling was assessed using pharmacologic or RNAi-mediated knock down approaches. Results: Short-term treatment with EPS inhibited proliferation of certain breast cancer cells (T47D, MDA-MB-468, HCC1428, MDA-MB-453) while having little effect on others (MCF-7, MDA-MB-231, BT549, ZR-75-30). EPS induced G1/G0 cell cycle arrest of T47D cells while increasing apoptosis of MDA-MB-468 cells. EPS also enhanced aggressive phenotypes in T47D cells including cell migration and cancer stem cell survival. Long-term treatment with EPS (months) led to resistance in vitro and promoted tumor growth in immunocompromised mice. RNA-sequence analysis showed that EPS increased expression of pro-inflammatory pathways including STAT1 and NF-κB. IKKß and/or STAT1 signaling was necessary for EPS to modulate phenotypes of EPS sensitive breast cancer cells. Discussion: These results demonstrate a multifaceted role for an EPS molecule secreted by the probiotic bacterium B. subtilis on breast cancer cell phenotypes. These results warrant future studies in immune competent mice and different cancer models to fully understand potential benefits and/or side effects of long-term use of probiotics.

2.
Sensors (Basel) ; 23(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420558

RESUMO

Retinal optical coherence tomography (OCT) imaging is a valuable tool for assessing the condition of the back part of the eye. The condition has a great effect on the specificity of diagnosis, the monitoring of many physiological and pathological procedures, and the response and evaluation of therapeutic effectiveness in various fields of clinical practices, including primary eye diseases and systemic diseases such as diabetes. Therefore, precise diagnosis, classification, and automated image analysis models are crucial. In this paper, we propose an enhanced optical coherence tomography (EOCT) model to classify retinal OCT based on modified ResNet (50) and random forest algorithms, which are used in the proposed study's training strategy to enhance performance. The Adam optimizer is applied during the training process to increase the efficiency of the ResNet (50) model compared with the common pre-trained models, such as spatial separable convolutions and visual geometry group (VGG) (16). The experimentation results show that the sensitivity, specificity, precision, negative predictive value, false discovery rate, false negative rate accuracy, and Matthew's correlation coefficient are 0.9836, 0.9615, 0.9740, 0.9756, 0.0385, 0.0260, 0.0164, 0.9747, 0.9788, and 0.9474, respectively.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Tomografia de Coerência Óptica/métodos , Retina/diagnóstico por imagem , Valor Preditivo dos Testes
3.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-36534625

RESUMO

Melanotic neuroectodermal tumor of infancy (MNTI) is a neonatal tumor with progressive growth and high recurrence rate. Aggressive growth and localization of tumor often lead to significant cosmetic defects of cranial and facial bones. The authors report MNTI in a 6-month-old boy with lesion of the large fontanel. Total resection was followed by recurrence after 3 weeks. Repeated resection with subsequent radiotherapy was performed. The follow-up period was 6 months after repeated resection. There was no tumor growth throughout this period. Considering this case and world experience, we can conclude that treatment strategy for MNTI is still unclear.


Assuntos
Tumor Neuroectodérmico Melanótico , Masculino , Recém-Nascido , Humanos , Lactente , Tumor Neuroectodérmico Melanótico/patologia , Tumor Neuroectodérmico Melanótico/cirurgia , Crânio/patologia
4.
RSC Adv ; 12(17): 10198-10203, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36200125

RESUMO

A simple, new, green, and sensitive approach was established and validated for assay of the recently approved antineoplastic medication; darolutamide (DAR) in its authentic form, pharmaceutical formulation, and biological fluids fluorimetrically. This experiment relied on the native fluorescence of the cited drug and detects the ideal solvent utilized throughout the approach. The proposed approach was validated regarding linearity, accuracy, and precision. The calibration graph showed linearity over the range of 0.1-2.0 µg mL-1. The limit of detection and quantitation (LOD and LOQ) were 0.032 µg mL-1 and 0.09 µg mL-1, respectively. Because of the approach's high sensitivity, it was decided to spike the mentioned drug in plasma and urine samples. At last, checking for content uniformity was performed regarding the United States Pharmacopoeia (USP) by adjusting the proposed approach.

5.
Biomed Chromatogr ; 36(11): e5476, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35918842

RESUMO

A sensitive and simple sample pretreatment method based on a two-phase solvent bar microextraction (SBME) technique coupled with HPLC-diode array detector (DAD) was developed for simultaneous extraction and determination of trace amounts of furosemide and carbamazepine in human urine and plasma samples. The significance of operational factors on carbamazepine and furosemide extraction efficiency % (EE%) was screened using full factorial design (FFD) while central composite design (CCD) was used to model the entire process. A quadratic model was found convenient to correlate the extraction EE% of selected drugs with dominant experimental factors. A Pareto chart was also used to examine the importance of factors on drugs' EE%. The analytical performance of the method in urine and plasma samples demonstrated good linearity (R2 ˃ 0.992) with detection limits ranging from 4.2 to 10.9 µg L-1 , and extraction recovery over 89.45% for both drugs in urine and plasma samples. A comparison against published methods was also performed and the results revealed that the developed method exhibits a confident sensitivity, feasible operation, and simple analysis for both drugs. Finally, the practicability of the validated SBME-HPLC-DAD method was demonstrated by successfully applying it to the analysis of furosemide and carbamazepine in real patient urine samples.


Assuntos
Microextração em Fase Líquida , Benzodiazepinas , Carbamazepina , Cromatografia Líquida de Alta Pressão/métodos , Furosemida , Humanos , Microextração em Fase Líquida/métodos , Solventes
6.
Artigo em Russo | MEDLINE | ID: mdl-35170282

RESUMO

Depressed skull fractures (ping-pong) in the fetus and newborn are associated with birth canal pathology, maternal trauma and birth trauma following instrumental delivery. The authors report a newborn with a depressed skull fracture (ping-pong) who underwent minimally invasive neurosurgical lifting of bone fragment through a burr hole. Strategy and methods of treatment of similar depressed skull fractures were comprehensively discussed. Moreover, the authors proposed a brief algorithm for the use of vacuum systems and various surgical techniques, including follow-up depending on type, cause, size of the fracture and concomitant intracranial lesions.


Assuntos
Fratura do Crânio com Afundamento , Fraturas Cranianas , Humanos , Recém-Nascido , Crânio , Fratura do Crânio com Afundamento/diagnóstico por imagem , Fratura do Crânio com Afundamento/cirurgia , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/cirurgia , Trepanação
7.
Cureus ; 14(1): e21350, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35198267

RESUMO

Background After the emergence of the novel coronavirus disease pandemic, Saudi Arabia implemented lockdown restrictions to counter this infection and prevent its spread. There have been a lot of challenges to the majority of people, especially diabetic patients, which might result in an increased risk of developing complications and significant lifestyle changes, including physical inactivity, unhealthy diet, and psychological distress. Objective This study aims to assess the impact of coronavirus disease lockdown on children with type 1 diabetes (T1D) mellitus in Al-Khobar, Saudi Arabia. Methods This is a questionnaire-based cross-sectional study which was conducted in pediatric patients, aged ≤18 years old, with type I diabetes, who were attending the endocrine clinic at the King Fahd Hospital of the University (KFHU) in Al-Khobar, Saudi Arabia. A total of 250 patients were identified from the hospital databases, a total of 164 patients were included in the study, and one of the parents/guardians was interviewed through mobile phone after taking their consent. Results The medication compliance during the lockdown has significantly increased as the percentage of children who did not miss any dose of medications increased to 92.7% in comparison to 70.7% before the lockdown (P=0.000). Also, diabetic ketoacidosis (DKA)-related intensive care unit admission had significantly decreased during the lockdown (P=0.001). Regarding the number of consumed meals, it increased from 53.7% up to 68.3% before and during the lockdown period, respectively (P=0.005). In addition, there was no significant change in children's psychological health during the lockdown period (p= 0.123). Conclusion The study indicates that there was an increase in compliance to medications, a significant decrease in intensive care unit and emergency department admission due to hypo/hyperglycemia during the lockdown period. Medical practitioners are encouraged to educate diabetic patients regarding the importance of self-blood glucose monitoring, healthy lifestyle, psychological wellbeing, and regular follow-up through virtual clinics.

8.
J Neurol Sci ; 427: 117506, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087568

RESUMO

Epilepsy surgery is recommended in selected patients with Tuberous Sclerosis Complex (TSC). However, reports on predictive factors of seizure outcome are variable. Here we report on seizure and cognitive outcome of 35 TSC patients who received surgery for refractory epilepsy in 7 Italian centers over a period of 22 years (1997-2019). The rate of seizure-free individuals at last follow-up (mean 7.5 years, range 1-21 years) was 51%. Patients with longer follow-up (≥10 years) had a lower rate of Engel I outcome (11.1%) than those who received surgery in the last 10 years (65.4%, p = 0.003). Factors associated with Engel II, III, IV outcome in our cohort included: high number of cortical tubers (≥5); presence of subependymal nodules (SENs); seizure onset before age 1 year; and multifocal interictal epileptic discharges (IEDs) on electroencephalogram (EEG). A subset of patients evaluated with Vineland Adaptive Behaviour Scales (VABS) showed developmental gains, in line with their developmental trajectories, but no improvement in standard scores after surgery was noted. Our study demonstrates that the rates of successful seizure outcome of epilepsy surgery in TSC have improved in the last 10 years. More than half of the patients achieved seizure freedom, and a high proportion of affected individuals experienced a reduction in seizure burden and in antiseizure medications. A comprehensive assessment after surgery should be performed in TSC patients to evaluate the overall neurodevelopmental outcome, as measures that are based only on seizure control do not adequately identify the benefits of surgery on global functioning in these patients.


Assuntos
Epilepsia , Esclerose Tuberosa , Eletroencefalografia , Epilepsia/etiologia , Epilepsia/cirurgia , Humanos , Lactente , Estudos Retrospectivos , Convulsões/epidemiologia , Convulsões/etiologia , Convulsões/cirurgia , Resultado do Tratamento , Esclerose Tuberosa/complicações , Esclerose Tuberosa/cirurgia
9.
Cereb Cortex ; 27(8): 4229-4243, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28525604

RESUMO

A description of the spatiotemporal dynamics of human cortical activity during cognitive tasks is a fundamental goal of neuroscience. In the present study, we employed stereo-EEG in order to assess the neural activity during tool-action observation. We recorded from 49 epileptic patients (5502 leads) implanted with intracerebral electrodes, while they observed tool and hand actions. We deconstructed actions into 3 events-video onset, action onset, and tool-object contact-and assessed how different brain regions respond to these events. Video onset, with actions not yet visible, recruited only visual areas. Aligning the responses at action onset, yielded activity in the parietal-frontal manipulation circuit and, selectively for tool actions, in the left anterior supramarginal gyrus (aSMG). Finally, by aligning to the tool-object contact that signals the achievement of the main goal of the observed action, activations were found in SII and dorsal premotor cortex. In conclusion, our data show that during tool-action observation, in addition to the general action observation network there is a selective activation of aSMG, which exhibits internally different patterns of responsiveness. In addition, neural responses selective for the contact between the tool and the object were also observed.


Assuntos
Córtex Cerebral/fisiologia , Percepção de Movimento/fisiologia , Destreza Motora , Adulto , Córtex Cerebral/fisiopatologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Epilepsia Resistente a Medicamentos/cirurgia , Eletrocorticografia , Epilepsias Parciais/fisiopatologia , Epilepsias Parciais/cirurgia , Feminino , Ritmo Gama , Mãos , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa
10.
Oncotarget ; 7(47): 77291-77305, 2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27764792

RESUMO

The receptor tyrosine kinase AXL promotes migration, invasion, and metastasis. Here, we evaluated the role of AXL in endometrial cancer. High immunohistochemical expression of AXL was found in 76% (63/83) of advanced-stage, and 77% (82/107) of high-grade specimens and correlated with worse survival in uterine serous cancer patients. In vitro, genetic silencing of AXL inhibited migration and invasion but had no effect on proliferation of ARK1 endometrial cancer cells. AXL-deficient cells showed significantly decreased expression of phospho-AKT as well as uPA, MMP-1, MMP-2, MMP-3, and MMP-9. In a xenograft model of human uterine serous carcinoma with AXL-deficient ARK1 cells, there was significantly less tumor burden than xenografts with control ARK1 cells. Together, these findings underscore the therapeutic potentials of AXL as a candidate target for treatment of metastatic endometrial cancer.


Assuntos
Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Proteínas da Matriz Extracelular/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias do Endométrio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Gradação de Tumores , Invasividade Neoplásica , Transplante de Neoplasias , Fosforilação , Prognóstico , Transdução de Sinais , Análise de Sobrevida , Regulação para Cima , Receptor Tirosina Quinase Axl
11.
Sci Rep ; 6: 20597, 2016 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-26854202

RESUMO

Low heart rate variability (HRV) has been recognized to correlate with adverse cardiovascular (CV) outcomes in hemodialysis (HD) patients. It has been reported that HRV might be improved after HD, but whether the improved HRV after HD predicts a better CV prognosis remains to be determined. This study examined the ability of the change in HRV before and after HD in predicting overall and CV mortality in HD patients. This study enrolled 182 patients under maintenance HD. HRV was examined to assess changes before and after HD. The change in HRV (ΔHRV) was defined as post-HD HRV minus pre-HD HRV. During a median follow-up period of 35.2 months, 29 deaths (15.9%) were recorded. Multivariate analysis showed that decreased ΔLF% was associated with increased overall (hazard ratios [HR], 0.978; 95% confidence interval [CI], 0.961-0.996; p = 0.019) and CV mortality (HR, 0.941; 95% CI, 0.914-0.970; p < 0.001), respectively. Moreover, adding ΔLF% to a clinical model provided an additional benefit in the prediction of overall (p = 0.002) and CV mortality (p < 0.001). HRV change before and after HD (ΔHRV) is an useful clinical marker, and it is stronger than HRV before HD in predicting overall and CV mortality.


Assuntos
Doenças Cardiovasculares/etiologia , Frequência Cardíaca/fisiologia , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Idoso , Biomarcadores/análise , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/mortalidade , Eletrocardiografia , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Falência Renal Crônica/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Hormônio Paratireóideo/sangue , Modelos de Riscos Proporcionais , Fatores de Risco , Taxa de Sobrevida
12.
Aust Dent J ; 61(1): 62-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25819677

RESUMO

BACKGROUND: Tooth extractions lead to morphological changes of the alveolar ridge. For oral rehabilitation sufficient bone volume of the alveolar ridge is required. This clinical study compared the ability of Bio-Oss® Collagen to autogenous bone to preserve bone volume after tooth extraction. METHODS: A total of 17 patients with 20 extraction sites were examined. After extraction, 10 sockets were each filled with either autogenous bone or Bio-Oss® Collagen and covered with a resorbable membrane. The width of the alveolar ridge was measured postoperatively, and after 4 and 6 months respectively. Prior to implant insertion, a bone biopsy was taken from the grafted sites and evaluated histologically. RESULTS: The width of the alveolar ridge in the Bio-Oss® Collagen group decreased about 5.33 ± 6.62% after 4 months and 9.45 ± 10.51% after 6 months. The reduction in the group augmented with autogenous bone was 14.31 ± 21.41% after 4 months and 19.17 ± 8.38% after 6 months. No statistically significant differences were observed. The histological examination showed comparable area fractions of total bone in both groups (Bio-Oss® Collagen: 59.99 ± 24.23%; autogenous bone: 61.55 ± 25.13%; p = 1.0). CONCLUSIONS: The present study demonstrated that autogenous bone and Bio-Oss® Collagen are suitable for ridge preservation. However, both techniques could not entirely prevent tissue volume loss.

13.
Biomaterials ; 53: 634-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25890759

RESUMO

Currently, histological techniques are used to analyse implant-tissue-interactions. However, these methods are destructive and time-consuming. Furthermore, they require a large number of animals as longitudinal observations in one individual are not possible. The evaluation by non-destructive imaging techniques provides the opportunity to study the osseous integration with a reduced number of animals and a decreased biological variability. The present study examined the suitability of magnetic resonance imaging (MRI) to assess peri-implant bone formation exemplarily for a dental implant in a minipig model. Due to its compatibility to MR imaging polyetheretherketone (PEEK) coated with a thin layer of titanium was applied as implant material. Osseointegration was analysed within different peri-implant regions quantifying bone volume density and soft tissue content, which were assessed by MRI and histology, likewise. It could be proven that the examined regions showed differences in bone formation; the region adjacent to the implant apex turned out to be the most dynamic. Both methods led to comparable results with no significant differences regarding to the assessed parameters. Moreover, it was demonstrated that titanium coated PEEK showed a sufficient osseointegration and MRI provides a promising application in monitoring bone formation.


Assuntos
Implantes Dentários , Imageamento por Ressonância Magnética , Animais , Desenvolvimento Ósseo , Implantação Dentária Endóssea , Modelos Animais , Suínos , Porco Miniatura
14.
Hell J Nucl Med ; 17(3): 165-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25397621

RESUMO

Focal tracer uptake in the jaw during conventional bone scintigraphy is a quite frequent finding usually due to dental disease and seldom to other diseases including malignant disease. Methylene diphosphonate-technetium-99m ((99m)Tc-MDP) 3-phase bone scan is considered the most sensitive imaging method for the detection of jaw osteonecrosis at an early stage. This finding can also but seldom be seen in patients undergoing palliative radionuclide treatment for bone metastases. In conclusion, focal jaw lesions are usually benign and of dental origin. In a small percentage of cancer patients of about 4.3%, jaw lesions as diagnosed among 347 cases of various carcinomas may be due to malignancy. Unfortunately, the number of studies is small, most of them are retrospective and few show biopsy results.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/metabolismo , Neoplasias Maxilomandibulares/diagnóstico por imagem , Neoplasias Maxilomandibulares/metabolismo , Compostos Organometálicos/farmacocinética , Compostos Organofosforados/farmacocinética , Diagnóstico Diferencial , Humanos , Achados Incidentais , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual
15.
Int J Comput Assist Radiol Surg ; 9(6): 1087-97, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24748210

RESUMO

PURPOSE: StereoElectroEncephaloGraphy (SEEG) is done to identify the epileptogenic zone of the brain using several multi-lead electrodes whose positions in the brain are pre-operatively defined. Intracranial hemorrhages due to disruption of blood vessels can cause major complications of this procedure ([Formula: see text]1%). In order to increase the intervention safety, we developed and tested planning tools to assist neurosurgeons in choosing the best trajectory configuration. METHODS: An automated planning method was developed that maximizes the distance of the electrode from the vessels and avoids the sulci as entry points. The angle of the guiding screws is optimized to reduce positioning error. The planner was quantitatively and qualitatively compared with manually computed trajectories on 26 electrodes planned for three patients undergoing SEEG by four neurosurgeons. Quantitative comparison was performed computing for each trajectory using (a) the Euclidean distance from the closest vessel and (b) the incidence angle. RESULTS: Quantitative evaluation shows that automatic planned trajectories are safer in terms of distance from the closest vessel with respect to manually planned trajectories. Qualitative evaluation performed by four neurosurgeons showed that the automatically computed trajectories would have been preferred to manually computed ones in 30% of the cases and were judged good or acceptable in about 86% of the cases. A significant reduction in time required for planning was observed with the automated system (approximately 1/10). CONCLUSION: The automatic SEEG electrode planner satisfied the essential clinical requirements, by providing safe trajectories in an efficient timeframe.


Assuntos
Eletrodos Implantados , Eletroencefalografia/métodos , Epilepsia/cirurgia , Adulto , Feminino , Lobo Frontal/cirurgia , Humanos , Hemorragias Intracranianas/prevenção & controle , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Técnicas Estereotáxicas , Lobo Temporal/cirurgia
16.
Int J Surg ; 12(5): 60-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24189298

RESUMO

Reconstructing continuity defects of the mandible is still challenging for surgeons. The currently applied conventional titanium bridging plates have considerable rates of complications. Now, a new technology enables an individual shape-identical creation of a mandibular implant in a form-board design by the method of LaserCUSING using pure titanium. This technology has been successfully performed in previous examinations to individually reconstruct mandibular continuity defects. This pilot study evaluated the surgical procedure in 10 female Göttingen mini pigs. First, a computed tomography scan from a mini pig cranium was performed. A three-dimensional model of the mandible was designed by data conversion. Based on the data, a customized mandibular implant resembling the natural shape was virtually created and manufactured. Then, a continuity defect of the left mandible was created in a standardized way. The implants were inserted into the defect and the wounds were allowed to heal for 21, 35, 56 and 180 days. During the healing period, no signs of inflammation or infection were observed. After the sacrifice of the minipigs the mandibles were resected. Histological microsections using Donath's sawing and grinding technique were manufactured and stained with Masson Goldner trichrome staining. The histomorphological results showed a pronounced ossification at the outer and inner surface of the implants. This animal study describes a promising approach to optimize customized implants for the application in humans.


Assuntos
Substitutos Ósseos , Mandíbula/cirurgia , Próteses e Implantes , Desenho de Prótese , Animais , Desenho Assistido por Computador , Feminino , Cabeça/diagnóstico por imagem , Histocitoquímica , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Mandíbula/fisiologia , Projetos Piloto , Radiografia , Distribuição Aleatória , Suínos , Porco Miniatura , Titânio , Cicatrização/fisiologia
17.
J Biomed Mater Res A ; 102(7): 2334-44, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23946280

RESUMO

An improved osseous integration of dental implants in patients with lower bone quality is of particular interest. The aim of this study was to evaluate the effect of artificial extracellular matrix implant coatings on early bone formation. The coatings contained collagen (coll) in conjunction with either chondroitin sulfate (CS) or sulfated hyaluronan (sHya). Thirty-six screw-type, grit-blasted, and acid-etched titanium implants were inserted in the mandible of 6 minipigs. Three surface states were tested: (1) uncoated control (2) coll/CS (3) coll/sHya. After healing periods of 4 and 8 weeks, bone implant contact (BIC), bone volume density (BVD) as well as osteoid related parameters were measured. After 4 weeks, control implants showed a BIC of 44% which was comparable to coll/CS coated implants (48%) and significantly higher compared to coll/sHya coatings (37%, p = 0.012). This difference leveled out after 8 weeks. No significant differences could be detected for BVD values after 4 weeks and all surfaces showed reduced BVD values after 8 weeks. However, at that time, BVD around both, coll/CS (30%, p = 0.029), and coll/sHya (32%, p = 0.015), coatings was significantly higher compared to controls (22%). The osteoid implant contact (OIC) showed no significant differences after 4 weeks. After 8 weeks OIC for controls was comparable to coll/CS, the latter being significantly higher compared to coll/sHya (0.9% vs. 0.4%, p = 0.012). There were no significant differences in osteoid volume density. In summary, implant surface coatings by the chosen organic components of the extracellular matrix showed a certain potential to influence osseointegration in vivo.


Assuntos
Desenvolvimento Ósseo , Sulfatos de Condroitina/química , Materiais Revestidos Biocompatíveis , Colágeno/química , Ácido Hialurônico/química , Modelos Animais , Próteses e Implantes , Animais , Suínos , Porco Miniatura
18.
Oncogene ; 33(43): 5065-77, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24141788

RESUMO

Y-box binding protein-1 (YB-1) is highly expressed in tumors and it participates in various cellular processes. Previous studies indicated that YB-1 binds to mispaired DNA and interacts with several mismatch repair (MMR)-related factors. However, its role in the MMR system remains undefined. Here, we found that YB-1 represses mutS homolog 6 (MSH6)-containing MMR complex formation and reduces MutSα mismatch binding activity by disrupting interactions among MMR-related factors. In an effort to elucidate how YB-1 exerts this inhibitory effect, we have identified two functional proliferating cell nuclear antigen (PCNA)-interacting protein (PIP)-boxes that mediate YB-1/PCNA interaction and locate within the C-terminal region of YB-1. This interaction is critical for the regulatory role of YB-1 in repressing MutSα mismatch binding activity, disrupting MutSα/PCNA/G/T heteroduplex ternary complex formation and inhibiting in vitro MMR activity. The differential regulation of 3' and 5' nick-directed MMR activity by YB-1 was also observed. Moreover, YB-1 overexpression is associated with the alteration of microsatellite pattern and the enhancement of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced and spontaneous mutations. Furthermore, upregulation of other PIP-box-containing proteins, such as myeloid cell leukemia-1 (Mcl-1) and inhibitor of growth protein 1b (ING1b), has no impact on MMR complex formation and mutation accumulation, thus revealing the significant effect of YB-1 on regulating the MMR system. In conclusion, our study suggests that YB-1 functions as a PCNA-interacting factor to exert its regulatory role on the MMR process and involves in the induction of genome instability, which may partially account for the oncogenic potential of YB-1.


Assuntos
Reparo de Erro de Pareamento de DNA , Proteínas de Ligação a DNA/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Sítios de Ligação , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Metilnitronitrosoguanidina/farmacologia , Instabilidade de Microssatélites , Mutação , Antígeno Nuclear de Célula em Proliferação/química , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Proteína 1 de Ligação a Y-Box/química , Proteína 1 de Ligação a Y-Box/genética
19.
Eur J Gynaecol Oncol ; 34(2): 197-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23781599

RESUMO

The authors describe the occurrence of a 55-year-old female patient presenting with a vulvar melanoma, endometrial polyp, and a prior history of breast carcinoma excised from the left chest wall, radiotherapy, chemotherapy, and tamoxifen maintenance for two years. This case exemplified second primary vulvar melanoma following breast cancer and supported that radiotherapy might play a role in the onset of secondary cancer. This case report also emphasizes the onset of endometrial polyp induced by tamoxifen.


Assuntos
Neoplasias da Mama/terapia , Neoplasias do Endométrio/patologia , Melanoma/patologia , Segunda Neoplasia Primária/patologia , Pólipos/patologia , Neoplasias Vulvares/patologia , Neoplasias do Endométrio/etiologia , Feminino , Humanos , Melanoma/etiologia , Pessoa de Meia-Idade , Segunda Neoplasia Primária/etiologia , Pólipos/etiologia , Radioterapia/efeitos adversos , Tamoxifeno/efeitos adversos , Neoplasias Vulvares/etiologia
20.
Clin Oral Investig ; 17(3): 887-96, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22699659

RESUMO

OBJECTIVES: Botulinum toxin A (Botox) is increasingly used for treatment of muscle hyperfunction. For a better understanding of the possible morphologic and chewing changes in patients induced by a therapy with Botox, muscle fiber and myosin heavy chain (MyHC) mRNA alterations were examined in this animal study. MATERIALS AND METHODS: The investigation was carried out on 14-week-old pigs (seven treated animals, eight controls; calculated animal size with a power of 0.5). To initialise the total immobilisation of the right masseter, the Botox injection was distributed into ten areas. After a 56-day period, muscle tissue was taken from the left and right side of the masseter (three regions), temporal (two regions), medial pterygoid and geniohyoid muscles using a standardized method. The muscle fiber cross sections were examined immunohistochemically. Fiber staining was accomplished with antibodies to specific MyHC isoforms. The MyHC mRNA changes were analysed using real-time RT-PCR. RESULTS: Muscles adapt to such stress by changing fiber types and MyHC mRNA content. Paralysed masseters display atrophic changes while other masticatory muscles show hypertrophic changes. The results indicated that the typical distributions of type IIa und IIb fiber types in masticatory muscles were increased in the masseter muscles due to Botox application. On the other hand, the masseters without Botox in the treated group showed a significant increase of type I MyHC. CONCLUSIONS: Application of Botox may lead to uncontrolled structural changes in affected and unaffected muscles. CLINICAL RELEVANCE: Treatment of muscle hypertrophy with Botox may cause muscle imbalance.


Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Paralisia Facial/tratamento farmacológico , Músculo Masseter/efeitos dos fármacos , Músculos da Mastigação/patologia , Cadeias Pesadas de Miosina/genética , Miosinas de Músculo Esquelético/genética , Animais , Toxinas Botulínicas Tipo A/uso terapêutico , Hipertrofia , Músculos da Mastigação/química , Músculos da Mastigação/efeitos dos fármacos , Denervação Muscular , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/patologia , Cadeias Pesadas de Miosina/efeitos dos fármacos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real , Suínos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...