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Automated vehicles could increase the risk of motion sickness because occupants are not involved in driving and do not watch the road. This paper aimed to investigate the influence of motion predictability on motion sickness in automated vehicles, as better motion anticipation is believed to mitigate motion sickness. In a simulator-based study, twenty participants experienced two driving conditions differing only in turn directions. The repetitive condition featured a repeating turn direction pattern. The non-repetitive condition contained pseudo-randomly ordered turn directions. To mimic an 'eyes-off-the-road' setting and prevent visual motion anticipation, road visuals were omitted. No significant differences in sickness or head motion, a metric for motion anticipation, were found between the conditions. No participant recognised the repeating turn pattern. This suggests no increased motion anticipation in the repetitive condition, possibly due to a reduced ability to recognise a repeating motion pattern in one degree of freedom within more complex motion.
Motion anticipation is believed to mitigate motion sickness. However, in this simulator-based study on automated vehicles, no significant differences in motion anticipation or sickness were observed between repetitive and non-repetitive turn directions. Recognition of a repeating motion pattern in one degree of freedom might be diminished when it is part of more complex motion.
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Highly polished 3, 4, and 5 mol% yttria-stabilized zirconia and CAD/CAM composite resin samples were prepared, and the influence of surface roughness (Ra and Sa, 21 areas/group), wettability (contact angle and surface energy, 3 samples/group), and surface chemical composition (2 samples/group) on single-strain bacterial adhesion models (Porphyromonas gingivalis, Streptococcus oralis, Streptococcus sanguinis, Streptococcus gordonii, and Streptococcus mutans) were compared via fluorescent staining with graphical analysis (21 areas/group). Statistical analysis was performed using the Shapiro-Wilk test followed by one-way analysis of variance with Tukey's test or the Kruskal-Wallis test with Dunn's test (α=0.05) and linear regression. For dental zirconia with the same surface roughness, the yttria content did not significantly influence the initial bacterial adhesion. However, higher bacterial adhesion was detected for the composite resin owing to its high C, O, and Si contents. There was no correlation between surface energy and bacterial adhesion for any bacterial strain (p<0.005).
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Aderência Bacteriana , Resinas Compostas , Materiais Dentários , Propriedades de Superfície , Zircônio , Zircônio/química , Resinas Compostas/química , Materiais Dentários/química , Técnicas In Vitro , Ítrio/química , Polimento Dentário/métodos , Teste de Materiais , Streptococcus , Streptococcus mutans , Molhabilidade , Streptococcus gordonii/fisiologia , Streptococcus sanguis , Porphyromonas gingivalis , Corantes FluorescentesRESUMO
PURPOSE: The effect of chronic low dose-rate radiation exposure on cancers was investigated by analyzing the data of mice experiments conducted at the Institute for Environmental Sciences (IES). This analysis focuses on the differences between malignant lymphomas and solid cancers. MATERIALS AND METHODS: The analysis is conducted based on the mathematical model introduced in our previous work. The model is expanded to analyze malignant lymphomas and solid cancers separately. Using the expanded model, the effect of chronic low dose-rate radiation on malignant lymphomas and solid cancers are discussed based on their occurrences, progressions, and mortalities. RESULTS: Non-irradiated control group and 20 mGy/day × 400 days irradiated groups are analyzed. The analysis showed that radiation exposure shortened mean life expectancy for both malignant lymphomas and solid cancers (shorter by 89.6 days for malignant lymphomas and 149.3 days for solid cancers). For malignant lymphomas, both the occurrence and the progression are affected by radiation exposure. The mean age at which malignant lymphoma developed in mice was shortened by 32.7 days and the mean progression period was shortened by 57.3 days. The occurrence of solid cancer is also affected by radiation exposure, wherein the mean age at which solid cancer develops was shortened by 147.9 days. However, no significant change in progression period of solid cancers was seen in the analysis. CONCLUSIONS: The analysis showed that the occurrence and mean lifespan are affected in both malignant lymphomas and solid cancers. The shortening of the progression period is only seen in malignant lymphoma, no significant change was observed in solid cancers.
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Relação Dose-Resposta à Radiação , Linfoma , Neoplasias Induzidas por Radiação , Animais , Camundongos , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/patologia , Linfoma/etiologia , Linfoma/patologia , Neoplasias/radioterapia , Neoplasias/patologia , Neoplasias/etiologia , Exposição à Radiação/efeitos adversos , Doses de Radiação , Feminino , MasculinoRESUMO
The patient was a 54-year-old male at the time of initial examination. He was aware of numbness and weakness in the left hemisphere of his body and came to see the hospital. He was diagnosed with brain metastasis of lung cancer and started treatment(cT2N0M1[Brain]). He underwent gamma knife for the head lesion and nivolumab for the lung lesion. The patient's lesions shrank with the success of the medical treatment, but recurred with small intestinal metastasis. He underwent a partial resection of the small intestine and was treated again with nivolumab, which resulted in a complete response. He is currently alive without recurrence. We have experienced a very rare case of recurrence-free survival after treatment for brain metastasis and small intestinal metastasis of lung cancer.
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Neoplasias Encefálicas , Neoplasias Intestinais , Neoplasias Pulmonares , Humanos , Masculino , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Pessoa de Meia-Idade , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Neoplasias Intestinais/cirurgia , Neoplasias Intestinais/patologia , Neoplasias Intestinais/secundário , Neoplasias Intestinais/terapia , Terapia Combinada , Fatores de Tempo , Recidiva , Radiocirurgia , Nivolumabe/uso terapêutico , Intestino Delgado/patologia , Antineoplásicos Imunológicos/uso terapêuticoRESUMO
We explored how body movements influence illusory body motion intensity and their association with motion sickness. Twelve individuals who were seated in the back of a passenger car, performed a visual task and were subjected to continuous rotations followed by driving in a straight line. The body movements during and immediately after rotation were categorized as follows: (A) upright posture; (B) leaning the body in the yaw direction towards the rotation center, returning the yaw angle to zero upon transitioning to straight line travel, and tilting in the roll condition and gradually returning to upright; and (C) tilting in roll conditions towards the centripetal direction during rotation and becoming upright upon transitioning to straight line travel. In experiment-1, after spanning half a lap, participants reported the intensity of the illusory motion experienced during straight line travel immediately after rotation. In experiment-2, after travelling up to eight laps, the participants reported the symptom level of motion sickness experienced during two straight sections per lap using the MIsery SCale (MISC). Experiment-1 revealed that condition (C) had significantly larger illusions than Conditions (A) and (B). Experiment-2 revealed that motion sickness progressed significantly more in Condition (C) than in Condition (A). A significant positive correlation was found between the observed MISC and the illusion strength. Our findings suggest that body movements during and immediately after continuous rotation have a significant impact on the illusion strength. Additionally, illusory motion could serve as an indicator of impending motion sickness.
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Ilusões , Percepção de Movimento , Enjoo devido ao Movimento , Humanos , Enjoo devido ao Movimento/fisiopatologia , Masculino , Feminino , Rotação , Adulto , Ilusões/fisiologia , Adulto Jovem , Percepção de Movimento/fisiologia , Movimento/fisiologia , Condução de Veículo , Postura/fisiologiaRESUMO
Cellulose nanofibrils (CNFs) exhibit excellent mechanical properties and are used to reinforce various composites. The effects of incorporating CNFs into commercial mineral trioxide aggregate (MTA) cements (NEX MTA (NEX) and ProRoot® MTA (PR)) on the underwater setting properties, compressive strength, and flowability were estimated in this study. NEX mixed without CNFs disintegrated after water immersion. NEX mixed with CNF-suspended solutions showed good setting properties under water immersion and a similar compressive strength, which was kept in air (100% relative humidity). PR did not degrade after water immersion, regardless of the presence of CNFs, and no significant difference in the compressive strength caused by CNFs incorporation was detected. The relative flowability of the NEX mixture decreased with increasing CNFs content up to 1.0 w/v%. The application of CNF-incorporated MTA in various dental cases is promising because CNFs prevent the water-immersion-dependent collapse of some MTA cements immediately after mixing.
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Celulose , Materiais Restauradores do Canal Radicular , Óxidos , Compostos de Cálcio , Água , Silicatos , Compostos de Alumínio , Combinação de MedicamentosRESUMO
PURPOSE: In this paper, we described our mathematical model for radiation-induced life shortening in detail and applied the model to the experimental data on mice to investigate the effect of radiation on cancer-related life-shortening. MATERIALS AND METHODS: Our mathematical model incorporates the following components: (i) occurrence of cancer, (ii) progression of cancer over time, and (iii) death from cancer. We evaluated the progression of cancer over time by analyzing the cancer incidence data and cumulative mortalities data obtained from mice experiments conducted at the Institute for Environmental Sciences (IES). RESULTS: We analyzed non-irradiated control and 20 mGy/day × 400 days irradiated groups. In the analysis, all malignant neoplasms were lumped together and referred to as 'cancer'. Our analysis showed that the reduction in lifespan (104 days in median) was the result of the early onset of cancer (68 days in median) and the shortening of the cancer progression period (48 days in median). CONCLUSIONS: We described in detail our mathematical model for radiation-induced life-shortening attributed to cancer. We analyzed the mice data obtained from the experiment conducted at the IES using our model. We decomposed radiation-induced life-shortening into the early onset of cancer and the shortening of the cancer progression period.
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Neoplasias Induzidas por Radiação , Camundongos , Animais , Doses de Radiação , Relação Dose-Resposta à Radiação , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/patologia , Raios gama , Modelos TeóricosRESUMO
In this study, fine powders of tristrontium aluminate (S3A) and distrontium cerate (S2Ce) cement were prepared using a dry grinding process, and their mechanical and ion dissolution properties were estimated. Fine cements showed the particles about 10 µm in diameter or smaller with sharp particle size distribution curves. The setting reaction of the fine cements was rapid; therefore, a 0.1% w/v of citric acid solution was used as the retarder. The compressive strengths of the fine cements were improved compared to those of the coarse cements at both 1 and 28 days after mixing at a water/powder ratio (W/P) of 0.4. The dissolution of Sr and Al ions from fine S3A cement was enhanced. However, the relative flowability decreases with fine grinding. Further studies on flowability, handling property are required. Additionally, the biological effects of endodontic cement should be studied both in vitro and in vivo.
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Cimentos Dentários , Estrôncio , Cimentos de Ionômeros de Vidro , Água , Cimentos Ósseos , Força Compressiva , Pós , Teste de MateriaisRESUMO
A 78-year-old male patient was referred to another hospital for cecal cancer and metastatic liver tumor. After open ileocecal resection, he was referred to our hospital for treatment of liver lesions. CT scan showed a lesion with contrast effect of approximately 60 mm in S8, and the patient was judged to be resectable by right lobe resection. However, considering his age and the possibility of latent disease, it was decided to introduce preoperative chemotherapy. After 4 courses of XELOX, although the ICG worsened from 9% to 18% after chemotherapy, the tumor was reduced to approximately 30 mm. The patient underwent an open anterior segment resection of the liver. Colorectal cancer guidelines recommend that surgical resection is the first-line treatment for resectable liver metastases and that preoperative adjuvant chemotherapy should not be given to patients. In this report, we describe a case in which a liver metastasis was safely resected with chemotherapy.
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Neoplasias do Ceco , Neoplasias Hepáticas , Masculino , Humanos , Idoso , Neoplasias do Ceco/tratamento farmacológico , Neoplasias do Ceco/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Hepatectomia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/secundárioRESUMO
There is a liver damage in a serious side effect of regorafenib. Case 1 was a 54-year-old woman, and she had an operation of rectal cancer and metastasized to multiple organs afterwards and started regorafenib as third-line. Erythema exudativum multiform developed on the 8th day after a start and regorafenib was canceled once and reduced on the 21st day when a skin symptom was relieved and restarted. However, because a significant rise of AST, ALT, T -Bil was recognized afterwards, regorafenib was canceled on the 27th day and enforced steroid pulse therapy and was relieved afterwards. Case 2 was a 61-year-old woman, and she had an operation of ascending colon cancer, ovarian metastasis and peritoneum dissemination. Regorafenib was started by frequent occurrence lung metastasis, cancerous pleurisy afterwards as fifth-line. Dissemination erythema developed on the 16th day and a liver damage developed on the 22nd day. Because a rise of AST, ALT went and was prolonged, liver biopsy was enforced in a cause close inspection purpose on the 45th day. A medicamentosus liver damage was diagnosed. The liver enzyme decreased afterwards. It may be easy to make the liver damage by regorafenib serious, and attention is necessary.
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Neoplasias do Colo , Neoplasias Ovarianas , Piridinas , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo/patologia , Compostos de Fenilureia/efeitos adversos , Neoplasias Ovarianas/tratamento farmacológico , Eritema/induzido quimicamente , Fígado/patologiaRESUMO
The authors performed a combined analysis using the data obtained from continuous low dose rate irradiation experiments on mice conducted at the Institute for Environmental Sciences, namely, cancer incidence data and lifespan data. They estimated the length of cancer progression period, which is difficult to assess experimentally. The combined analysis showed that the mean cancer progression period is 173 d in the control group and 103 d in the irradiated group.
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Longevidade , Neoplasias Induzidas por Radiação , Relação Dose-Resposta à Radiação , Humanos , Incidência , Longevidade/efeitos da radiação , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/etiologiaRESUMO
The concept of radiation-induced aging is revisited from the viewpoint of a mathematical model. The effect of radiation on carcinogenesis is treated based on the Armitage-Doll multi-stage theory. The formula obtained for cancer incidence rate indicates that radiation dose can be explained in terms of time. Radiation-induced aging for acute and chronic exposures is described using age-specific cancer incidence rates as a measure of aging. It shows that accelerated aging is related to the dose rate, whereas premature aging is related to the cumulative dose, providing a simple and natural interpretation of radiation-induced aging. The usefulness of this approach is demonstrated by applying the formula to cancer prevalence data from mice chronically exposed to low dose-rate radiation.
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Senilidade Prematura , Neoplasias Induzidas por Radiação , Neoplasias , Envelhecimento , Senilidade Prematura/complicações , Animais , Carcinogênese , Incidência , Camundongos , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/etiologiaRESUMO
A battery-driven micro electromechanical system (MEMS) gas sensor has been developed for household safety when using natural gas. The heart of the MEMS gas sensor is a 7.5 at % Pt-SnO2 thin film catalyst deposited on the SnO2 sensor layer. The catalyst enhances the sensitivity to methane, though its structure under working conditions is unclear. In this study, in situ XAFS was applied to a 7.5 at % Pt-SnO2 catalyst layer deposited on a Si substrate, and we demonstrated that atomically dispersed Pt maintains its lattice position in SnO2 with a small loss of surrounding lattice oxygen in the presence of 1% CH4 and a more reducing gas of 1% H2 at the reaction temperature (703 K), i.e., no Pt aggregation is observed. The lost oxygen is easily recovered by re-oxidation by air. This work has revealed that the atomically dispersed Pt in the SnO2 lattice is the active structure and it is stable even under reaction conditions, which guarantees a long lifetime for the gas sensor.
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Background/purpose: Tristrontium aluminate (S3A) is a hydraulic cement with setting behavior similar to that of mineral trioxide aggregate (MTA). This study examined the biological effects of S3A on mouse dental papilla cells (MDPs) in vitro and on rat exposed pulps in vivo. Materials and methods: Extracts of S3A and MTA were prepared by immersing each cement in ultrapure water. MDPs were cultured with S3A or MTA extracts, and cell proliferation was evaluated with a tetrazolium-salt assay. Attachment of MDPs on the set cements was examined with scanning electron microscopy (SEM). mRNA expression of bone morphogenic protein (Bmp2), osteocalcin (Oc) and osteopontin (Opn) in MDPs exposed to S3A or MTA extracts was determined with reverse transcription-quantitative polymerase chain reaction. Mineralized nodule formation was evaluated with Alizarin Red S staining. Simulated body fluid (SBF)-dipped S3A was examined with SEM and energy dispersive X-ray analysis (EDX). Exposed molar pulps of male Wistar rats capped with S3A or MTA were histologically examined. Results: S3A extract did not inhibit proliferation of MDPs. Set S3A and MTA exhibited attachment of MDPs on their surface. S3A extract showed significantly higher mineralized nodule formation and mRNA expression of Bmp2, Oc, and Opn than did MTA extract. SBF-dipped S3A exhibited formation of surface precipitates, which were composed of Ca, P, Sr, and Al. Direct pulp capping with S3A and with MTA induced mineralized tissue repair of the exposed pulp. Conclusion: S3A possesses biocompatibility and pro-mineralization effects comparable to those of MTA.
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OBJECTIVES: To evaluate the effect of smear layer deproteinization using hypochlorous acid (HOCl) with/without metal chlorides (SrCl2 and ZnCl2) on the microtensile bond strength (µTBS) of two simplified adhesives to dentin. METHODS: Human dentin surfaces with a standardized smear layer were pretreated using a 105 ppm HOCl solution with/without SrCl2 (0.05 M, 0.1 M, 0.2 M, 0.4 M) or ZnCl2 (0.05 M, 0.1 M, 0.2 M) for 5 s, 15 s, or 30 s. After the deproteinizing solution was washed out with water for 5 s, 15 s, or 30 s, pretreated surfaces were bonded with one-step self-etch adhesive Bond Force II or universal adhesive Clearfil Universal Bond Quick, and µTBS was measured after 24 h. Additionally, the deproteinizing effects of HOCl solutions with/without the metal chlorides were compared by measuring changes in the amide:phosphate ratio using attenuated total reflection Fourier transform infrared spectroscopy. Statistical analysis was performed using multifactor ANOVA, Tukey's post hoc tests and t-tests (p < 0.05). RESULTS: Pretreatment with pure HOCl for 15 s and 30 s significantly decreased the amide:phosphate ratio (p < 0.05), indicating effective deproteinization, but the µTBS of both adhesives increased significantly only if HOCl was washed out for 30 s (p < 0.05). Increasing the concentrations of metal chlorides enabled shortening of the wash-out time down to 5 s while maintaining the improved µTBS (p < 0.05). The deproteinizing effect of HOCl was not significantly altered by the addition of metal chlorides (p > 0.05). SIGNIFICANCE: The effectiveness of smear layer deproteinization using HOCl can be improved by the addition of metal chlorides, as their increasing concentration allowed to shorten the wash-out time from 30 s down to 5 s.
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Colagem Dentária , Camada de Esfregaço , Amidas/análise , Amidas/farmacologia , Cloretos/análise , Cloretos/farmacologia , Cimentos Dentários/farmacologia , Dentina/química , Adesivos Dentinários/química , Humanos , Ácido Hipocloroso/análise , Ácido Hipocloroso/farmacologia , Teste de Materiais , Fosfatos/farmacologia , Cimentos de Resina/química , Resistência à TraçãoRESUMO
BACKGROUND/AIM: Although resection is effective for managing resectable liver metastases from colorectal cancer, the clinical significance of chemotherapy for such metastases has remained undetermined. Therefore, we conducted a phase II trial of perioperative chemotherapy with mFOLFOX6 to examine its efficacy. PATIENTS AND METHODS: A total of 41 patients were examined. The liver resection rate was the primary endpoint, whereas the response rate, adverse events, completion rate, liver injury rate, R0 resection rate, and histological results were the secondary endpoints. RESULTS: Overall, 34 (82.9%) patients underwent liver resection, and 77.4% and 100% had synchronous and metachronous liver metastases, respectively. The seven remaining patients did not undergo resection because of progressive disease. Moreover, 2, 15, 17, and 7 patients had a complete response, partial response, stable disease, and progressive disease, respectively, which indicated that the response rate was 41.5%. Regarding adverse events, three patients exhibited Grade 3 myelosuppression and one patient had gastrointestinal symptoms. On the basis of histopathological examination, 27, 5, and 2 patients belonged to grades 1a:1b, 2, and 3, respectively. Regarding liver injury, 29.4% had liver sinusoidal injury, whereas 11.7% had steatohepatitis. Meanwhile, all patients underwent postoperative chemotherapy. CONCLUSION: mFOLFOX6 is safe and yields favorable therapeutic effects. The indication for liver resection after a certain waiting period is clinically significant.
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We report a rare case of metastatic small intestine cancer originating from penile cancer triggered by intestinal obstruction, with some review of the literature. The case was a 78-year-old man at the first visit. Partial penile resection was performed for penile cancer. Histopathological findings were squamous cell carcinoma, and the surgical margin was negative. The stage at the time of the first surgery was T2N0M0, Stage â ¡. He came to the hospital with a complaint of abdominal pain 4 years after the operation. He was diagnosed with intestinal obstruction and was treated medically. He underwent medical treatment for 12 days, but did not improve, so he underwent laparoscopic ileus release. Surgical findings showed a neoplastic lesion in the abdominal cavity, and the site was obstructed, and partial resection of the small intestine including the neoplastic lesion was performed. Pathological examination revealed small intestinal metastasis of penile cancer. Postoperative intestinal obstruction improved and he was discharged without complications. After discharge, he underwent systemic chemotherapy at an outpatient clinic, but died of the primary disease 181 days after intestinal obstruction.
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Íleus , Obstrução Intestinal , Laparoscopia , Neoplasias Penianas , Idoso , Humanos , Íleus/etiologia , Íleus/cirurgia , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Laparoscopia/efeitos adversos , Masculino , Neoplasias Penianas/complicações , Neoplasias Penianas/patologia , Neoplasias Penianas/cirurgiaRESUMO
BACKGROUND: Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) predict the effects of fluoropyrimidine. However, the effects of FOLFOX therapy from the perspective of fluorouracil plus leucovorin (FL) remain underexplored. Hence, the relationship between mFOLFOX6 therapy (mFOLFOX6) and therapeutic efficacy was evaluated in patients with advanced/recurrent colorectal cancer (CRC). METHODS: Correlations between TS and DPD and primary and metastatic lesions in recurrent CRC were analyzed. Univariate and multivariate analyses of TS and DPD in combination with response rate (RR), progression-free survival (PFS), and overall survival (OS) were performed. RESULTS: A positive correlation between DPD and primary and metastatic lesions; correlations between TS and RR, DPD and RR, and PFS and OS; and significant differences for RR and DPD and TS, PFS and DPD, and OS and DPD were obtained. CONCLUSION: Nucleic acid metabolizing enzymes in primary lesions can be used to predict mFOLFOX6 efficacy in patients with recurrent CRC.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Colorretais , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Recidiva Local de Neoplasia , Timidilato Sintase/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/patologia , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , RNA MensageiroRESUMO
BACKGROUND/PURPOSE: Custom-made mouthguards (MGs) are strongly recommended for athletes during sports activities to prevent dental injuries. Athletes undergoing orthodontic treatment and wearing brackets require specially designed MGs for better protection and to create more space that will not hinder the planned orthodontic tooth movement. The purpose of this study was to fabricate effective, specially designed, custom-made MGs for patients or athletes with ongoing orthodontic treatment and to evaluate the shock absorption abilities of these MGs by an in vitro comparison of three different designs. MATERIALS AND METHODS: Three different types of specially designed, double-layered MGs, (i) creating inter bracket space inside the MG, (ii) embedding silicon wax inside the MG, and (iii) creating a buffer space with additional hard insertion, were fabricated from a simulated bracket attached model. Impact test was performed using a free-falling object on a vertical rod, and the strain-gauge system was used to assess the strain on the dentition with the MGs for the comparison of the shock absorption abilities of the three types. Analysis of variance at a significance level of 5% and multiple comparisons were performed for statistical analysis. RESULTS: The strains on the dentition with the MG creating buffer space with hard insertion were significantly lower than those with the other two types of MG (Pâ¯<â¯0.001). CONCLUSION: Insertion of a hard material and ensuring buffer space between the MG and the teeth and/or appliance was more effective than other methods of fabricating custom-made MGs to prevent sports-related traumatic dental injuries in athletes undergoing orthodontic treatment.
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This study investigated the influence of application/wash-out times of sodium hypochlorite (NaOCl) and hypochlorous acid (HOCl) on dentin bond strength of one-step self-etch adhesives (1-SEAs). Human coronal dentin discs with a standardized smear layer were pretreated with 6% NaOCl or 100 ppm HOCl for 5 s, 15 s, or 30 s, and washed out with water for 5 s, 15 s or 30 s with or without the application of Clearfil DC Activator (CDA). No pretreatment was used as a control. The discs were bonded with a 1-SEA (Bond Force II or Clearfil Universal Bond Quick) and microtensile bond strength (µTBS) was measured after 24 h. Pretreatment with NaOCl for 15 s and 30 s significantly decreased µTBS (p<0.05), irrespective of wash-out time. The application of CDA recovered µTBS but did not outperform the control group. Conversely, pretreatment with HOCl for 15 s and 30 s followed by 30 s wash-out time significantly increased µTBS of 1-SEAs (p<0.05), regardless of CDA application.