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Nowadays, a large amount and variety of plastic is being produced and consumed by human beings on an enormous scale. Microplastics and nanoplastics (MNPLs) have become ubiquitous since they can be found in many ecosystem components. Plastic particles can be found in soil, water, and air. The routes of human exposure are numerous, mainly involving ingestion and inhalation. Once ingested, these particles interact with the gastrointestinal tract and digestive fluids. They can adsorb substances such as additives, heavy metals, proteins, or even microorganisms on their surface, which can cause toxicity. During inhalation, they can be inhaled according to their respective sizes. Studies have reported that exposure to MNPLs can cause damage to the respiratory tract, creating problems such as bronchitis, asthma, fibrosis, and pneumothorax. The reports of boards and committees indicate that there is little data published and available on the toxicity of MNPLs as well as the exposure levels in humans. Despite the well-established concept of MNPLs, their characteristics, and presence in the environment, little is known about their real effects on human health and the environment.

The aim of this study was to evaluate the antimutagenic and antigenotoxic potential of grape juice concentrate in rodent organs exposed to cadmium chloride intoxication. A total of 15 Wistar rats were distributed into three groups (n = 5), as follows: control group (CTRL; nontreated group), cadmium group (Cd), and cadmium-grape juice group (Cd + GJ). Exposed animals received intraperitoneal injection of cadmium chloride (1.2 mg/kg body weight) diluted in water and, after 15 days, Cd + GJ group received grape juice concentrate for 15 days, by gavage (0.8 mL, 1.18 mg of polyphenols kg(-1) day(-1)). Grape juice concentrate was able to decrease genotoxic effects induced by cadmium in peripheral blood and liver cells as depicted by single cell gel (comet) and micronucleus assays. A decrease for anti-8-hydroxy-20-deoxyguanosine (8OHdG) expression in hepatocytes of animals exposed to cadmium and treated with grape juice concentrate was also detected. Higher CuZn-SOD activity was observed in liver cells of the Cd + GJ group. No remarkable differences were seen regarding Mn-SOD activity among groups. Taken together, our results demonstrate that grape juice concentrate was able to exert antimutagenic and antigenotoxic activities in blood and liver cells of rats exposed to cadmium.

The surgical treatment of mandibular condyle fractures currently offers several possibilities for stable internal fixation. In this study, a finite element model evaluation was performed of three different methods for osteosynthesis of low subcondylar fractures: (1) two four-hole straight plates, (2) one seven-hole lambda plate, and (3) one four-hole trapezoidal plate. The finite element model evaluation considered a load applied to the first molar on the contralateral side to the fracture. Results showed that, although the three methods are capable of withstanding functional loading, the lambda plate displayed a more homogeneous stress distribution for both osteosynthesis material and bone and may be a better method when single-plate fixation is the option., (Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

The aim of this study was to evaluate the anti-tumor activity of grape juice concentrate following medium-term oral carcinogenesis assay induced by 4-nitroquinoline 1-oxide (4NQO). A total of 30 male Wistar rats were distributed into five groups, as follows (n = 6 per group): Group 1 - negative control group (non-treated group); Group 2 - received grape juice concentrate at 1% dose by gavage for eight consecutive weeks; Group 3 - received 4NQO for 8 weeks at 20 ppm dose in drinking water daily; Group 4 - received 4NQO at 20 ppm dose during 8 weeks in drinking water and treated with grape juice concentrate at 1% dose orally by gavage for first 4 weeks after 4-NQO administration; Group 5 - received 4NQO at 20 ppm dose for 8 weeks in drinking water and treated with grape juice concentrate at 1% dose orally by gavage between the 5th and 8th weeks daily. Histopathological analysis revealed a decrease in hyperplasic and dysplastic lesions in Group 4. Groups 4 and 5 showed decreased COX-2 and TNF-alpha and eNOS gene expression. Grape juice concentrate also increased SOD Cu/Zn and catalase expression. However, Ki-67 immunoexpression was reduced at the promotion step of oral carcinogenesis (G5). Taken together, our results demonstrate that grape juice concentrate modulates rat tongue carcinogenesis as a result of anti-inflammatory activity, antioxidant activity and down-regulation of oral cells proliferation.

Polyphenols are present in foods and beverages, being related to sensorial qualities such as color, bitterness, and astringency, which are relevant in products such as wine, tea, and grape juice. These compounds occur naturally in forms varying from simple phenolic acids to complex polymerized tannins. Oral cancer is the most common head and neck cancer, and it often has a poor prognosis owing to local tumor invasion and frequent lymph node metastasis. Nowadays, chemoprevention is considered as a promising approach for controlling cancer as a result of specific natural products or synthetic agents able to suppress, reverse, or even prevent premalignancy before transformation into invasive cancer. The use of polyphenols as a chemopreventive agent is a suitable tool for modulation of the oral carcinogenesis process. The aim of this article is to present data generated from the use of polyphenols as a chemopreventive agent in oral carcinogenesis using in-vivo and in-vitro test systems. These results have shown that polyphenols are able to exert some chemopreventive action as a result of inducing cellular death, apoptosis, inhibition of tumor growth, and antioxidative properties. Therefore, this area warrants further investigation as a new approach that would apply not only to polyphenols but also to other phytochemicals used as promising therapeutic agents against oral human diseases, especially cancer.

Estrogen deprivation in postmenopausal women increases cardiovascular risk. Cardiovascular risk as a result of atherosclerosis is able to induce an inflammatory disease as far as cyclooxygenase-2 ( COX-2) expression. The purpose of the study was to investigate the role of COX-2 on exercise training in female mice low-density lipoprotein receptor knockout ( LDL-KO) with or without ovariectomy. A total of 15 female C57BL/6 mice and 15 female LDL-KO mice were distributed into 6 groups: sedentary control, sedentary control ovariectomized, trained control ovariectomized, LDL-KO sedentary, LDL-KO sedentary ovariectomized and LDL-KO trained ovariectomized. The ascending part of the aorta was stained with H&E and COX-2 expression was assessed by immunohistochemistry. Results revealed that ovariectomy as well as exercise training were not able to induce histopathological changes in mouse aorta for all groups investigated. LDL-KO mice demonstrated plaque containing cholesterol clefts, foamy histiocytes and mild inflammatory process for all groups indistinctly. Ovariectomy induced a strong immunoexpression in atherosclerosis lesion of LDL-KO mice. Nevertheless, a down-regulation of COX-2 expression was detected in LDL-KO trained ovariectomized when compared to LDL-KO sedentary. Our results are consistent with the notion that exercise training is able to modulate COX-2 expression in LDL-KO mice as a result of COX-2 down-regulation.

Muscle crush injury is a common trauma in the modern society after as a result of mass disasters after penetration into muscle by high-velocity projectiles, blunt external trauma, or by gravity during prolonged immobilization in comatose patients after head trauma, alcoholic or drug overdose. However, the underlying mechanisms linking these alterations are still not fully understood, especially in acute phase. The aim of this study was to analyze genomic instability in multiple organs of rats after acute muscle injury by means of single cell gel (comet) assay. Rats were randomly distributed into three groups (n=6 each group): control group and experimental groups: sacrificed 6h as 12h after muscle compression. These results indicate genetic damage in peripheral blood cells as depicted by tail moment results. DNA breakage was also detected in liver, lung and kidney cells after acute muscle injury for two times evaluated. Heart cells showed genetic damage after 12h following muscle compression. Taken together, our results suggest that acute muscle injury induces genomic damage in multiple organs of Wistar rats. This novel finding offers new insights into the underlying mechanisms of the relationship between acute crush muscle injury and clinical manifestations that can occur during limb compression., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

The purpose of this study was to evaluate the influence of helium-neon laser on bone repair of femur and tibia in rabbits. For this purpose, 15 New Zealand rabbits underwent bilateral bone damage (tibia and femur) using a spherical bur. Helium-neon laser light, at a fluency of 6 J∕cm(2) and wavelength of 632.8 nm was applied on the left legs (laser group). The right tibia or femur lesions (control group) served as negative control. All sections were histopathologically analyzed using HE sections and the morphometric data from bone tissue and hyaline cartilage were achieved. Histopathological analysis showed regular bone trabeculae covered by osteoblastic cells after 1 week in the group exposed to laser therapy from femur and tibia indistinctly. After 3 weeks, the laser group showed new bone formation coming from the bony walls in the femur and tibia as well. On the 5th week, well-defined trabecula undergoing remodeling process was detected for the most intense pattern in tibia only. Morphometric analysis revealed significant statistical differences (p < 0.05) in the bone tissue for the laser-exposed group on 1st and 3rd weeks. After 5th week, bone formation was increased to tibia only. Taken together, such findings suggest that helium-neon laser is able to improve bone repair in rabbits being the most pronounced effect in tibia.

Oral cancer is a common neoplasm worldwide. Its incidence and mortality have also increased over the past decades. It is characterized by poor prognosis and a low survival rate despite sophisticated surgical and radiotherapeutic modalities. Metastasis of oral cancer is a complex process involving detachment of cells from tumor tissue, regulation of cell motility and invasion, proliferation and evasion through the lymphatic system or blood vessels. In this review, we will focus on the current knowledge in metastasis from oral cancer regarding facts, such as incidence; stage, histopathology and grade of primary tumor; clinical manifestations; diagnosis; and treatment. Certainly, such information will contribute to the understanding of oral cancer pathogenesis.