• Title/Summary/Keyword: oral exposure

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Ameliorating Effect of Selenium against Arsenic Induced Male Reproductive Toxicity in Rats

  • Jalaludeen, Abdulkadhar Mohamed;Lee, Ran;Lee, Won Young;Kim, Dong Hoon;Song, Hyuk
    • Reproductive and Developmental Biology
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    • v.38 no.3
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    • pp.107-114
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    • 2014
  • Oral exposure of humans by excess amounts of arsenic may cause disturbances of the reproductive system. In the present study, such exposure was modelled in rats, with the support of sperm principal parameters and histopathological observations. Male Sprague-Dawley rats were randomly divided into three groups where the group I was served as a normal control, group II was received sodium meta-arsenite as arsenic (10 mg/kg b.w/day) and a combination of sodium meta-arsenite and sodium selenite (3 mg/kg b.w/day) in group III. After 6 weeks, there was no significant change in testis weight and in total motility of all the three experimental groups, whereas, rapid moving spermatozoa, moderately moving spermatozoa and slow moving spermatozoa were significantly decreased in arsenic treated rats as compared to control rats. The other sperm principal parameters like progressiveness, average path velocity, straightness linear velocity (VSL), curvilinear velocity (VCL), straightness, linearity sperm head elongation ratio, area, linearity amplitude of lateral head department (ALH) and beat cross frequency (BCF) were found to be reduced in arsenic intoxicated rats. These results are not correlated with the histological studies. On oral administration of selenium ameliorated the adverse effects of arsenic as compared to arsenic alone treated rats. Our findings clearly demonstrate that administration of selenium could prevent some of the deleterious effects of arsenic in the testis.

Emerging and Established Global Life-Style Risk Factors for Cancer of the Upper Aero-Digestive Tract

  • Gupta, Bhawna;Johnson, Newell W.
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.15
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    • pp.5983-5991
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    • 2014
  • Introduction: Upper aero-digestive tract cancer is a multidimensional problem, international trends showing complex rises and falls in incidence and mortality across the globe, with variation across different cultural and socio-economic groups. This paper seeks some explanations and identifies some research and policy needs. Methodological Approach: The literature illustrates the multifactorial nature of carcinogenesis. At the cellular level, it is viewed as a multistep process involving multiple mutations and selection for cells with progressively increasing capacity for proliferation, survival, invasion, and metastasis. Established and emerging risk factors, in addition to changes in incidence and prevalence of cancers of the upper aero-digestive tract, were identified. Risk Factors: Exposure to tobacco and alcohol, as well as diets inadequate in fresh fruits and vegetables, remain the major risk factors, with persistent infection by particular so-called "high risk" genotypes of human papillomavirus increasingly recognised as also playing an important role in a subset of cases, particularly for the oropharynx. Chronic trauma to oral mucosa from poor restorations and prostheses, in addition to poor oral hygiene with a consequent heavy microbial load in the mouth, are also emerging as significant risk factors. Conclusions: Understanding and quantifying the impact of individual risk factors for these cancers is vital for health decision-making, planning and prevention. National policies and programmes should be designed and implemented to control exposure to environmental risks, by legislation if necessary, and to raise awareness so that people are provided with the information and support they need to adopt healthy lifestyles.

Long-Term Exposure of Sildenafil Citrate on Sperm Parameters in Rat

  • Suresh, Sekar;Prithiviraj, Elumali;Venkatalakshmi, Nagella;Ganesh, Mohanraj Karthik;Ganesh, Lakshmanan;Lee, Hyun-Jeong;Prakash, Seppan
    • Reproductive and Developmental Biology
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    • v.35 no.4
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    • pp.435-439
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    • 2011
  • Sildenafil citrate (SIL) a phosphodiesterase 5 inhibitor (PDE5I) has been used for long time as a first line oral drug for erectile dysfunction. Though it has beneficial effects on erectile organ it also has some adverse effects in other cells and/or tissues related to reproductive system when exposed to longer duration. The objective of the present study is to evaluate the long term effect of SIL on sperm parameters in Wistar albino rat. The animals are divided into two groups, for group I - rats were treated with saline (vehicle alone) and group - II oral administration of 5 mg/kg b.w. of SIL was administrated orally once in a day for 120 days. At the end of the trial period animals were sacrificed and epididymal sperm were subjected to various analysis. Results showed significant reduction in sperm count, motility, viability and morphologically intact sperm in long term PDE5I exposed animals when compared to control. Acrosomal status and fertility test also showed significant reduction in long term PDE5I exposed animals. The present study clearly indicated that long term SIL has shown to induce alteration in sperm quality and quantity, leading to decline in fertility rate. Indicate that SIL impinge on spermatogenesis as well as epididymal function. Understanding the molecular down-stream events involved in long-term exposure to PDE5 inhibitor can be valuable to supervise on related infertility issues and to suggest corrective measures.

Effects of $CoCl_2$ on Osteogenic Differentiation of Human Mesenchymal Stem Cells

  • Moon, Yeon-Hee;Son, Jung-Wan;Moon, Jung-Sun;Kang, Jee-Hae;Kim, Sun-Hun;Kim, Min-Seok
    • International Journal of Oral Biology
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    • v.38 no.3
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    • pp.111-119
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    • 2013
  • Objective. To investigate the effects of the hypoxia inducible factor-1 (HIF-1) activation-mimicking agent cobalt chloride ($CoCl_2$) on the osteogenic differentiation of human mesenchymal stem cells (hMSCs) and elucidate the underlying molecular mechanisms. Study design. The dose and exposure periods for $CoCl_2$ in hMSCs were optimized by cell viability assays. After confirmation of $CoCl_2$-induced HIF-$1{\alpha}$ and vascular endothelial growth factor expression in these cells by RT-PCR, the effects of temporary preconditioning with $CoCl_2$ on hMSC osteogenic differentiation were evaluated by RT-PCR analysis of osteogenic gene expression, an alkaline phosphatase (ALP) activity assay and by alizarin red S staining. Results. Variable $CoCl_2$ dosages (up to $500{\mu}M$) and exposure times (up to 7 days) on hMSC had little effect on hMSC survival. After $CoCl_2$ treatment of hMSCs at $100{\mu}M$ for 24 or 48 hours, followed by culture in osteogenic differentiating media, several osteogenic markers such as Runx-2, osteocalcin and osteopontin, bone sialoprotein mRNA expression level were found to be up-regulated. Moreover, ALP activity was increased in these treated cells in which an accelerated osteogenic capacity was also verified by alizarin red S staining. Conclusions. The osteogenic differentiation potential of hMSCs could be preserved and even enhanced by $CoCl_2$ treatment.

AN ELECTRON MICROSCOPIC STUDY ON THE COBALT-60 IRRADIATION EFFECTS ON THE SALIVARY GLAND OF THE WHITE RAT (Cobalt-60 방사선조사가 백서의 타액선에 미치는 영향에 관한 전자현미경적 연구)

  • Park Chang Seo
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.15 no.1
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    • pp.27-40
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    • 1985
  • This study was undertaken to observe the histopathologic changes in salivary gland of the white rats when exposed to megavoltage fractionated dose of cobalt-60 irradiation and 78 female white rats, weighing approximately 180gm, were divided into control and 3 experimental groups. Irradiation on experimental groups was delivered by using 6000 curies MeV ALCYON cobalt-60 teletherapy unit with exposure rate 183 rads per minute, in source skin distance 80cm, 600 rads every 3 days. In experimental groups, Group Ⅰwas irradiated of total dose 1200 rads for a period of 6 days, Group Ⅱ was irradiated of total dose 2400 rads for a period of 12 days and Group Ⅲ was irradiated of total dose of 4800 rads for a period of 24 days. The animals were sacrificed serially at 3 hours, 6 hours, 10 hours, 1st day, 4th day, 7th day after each completion of irradiation exposure. At sacrifice, salivary glands were excised and examined microscopically and electromicroscopically. The results were as follows: 1. The acinar cells of parotid and submaxillary gland showed damage varied with dose, 1200 rads resulted in very mild injury while 4800 rads caused most extensive injury. 2. The acinar cells of parotid and submandibular gland showed similar ultrastructural alterations, appeared as pleomorphic nucleus, decreased numbers and pleomorphism of secretory granules, distention of rough endplasmic reticulum, expansion and pallor appearance of mitochondria, and hypertrophy of Golgi complex. 3. Parotid serous cells were the most sensitive components, displaying morphological alterations of radiation damage as early as 3 hours, followed by submandibular seromucinous cells and secretory tubular cells. 4. The mucous cells of sublingual gland, as well as the whole ductal lining cells of each salivary gland, displayed no significant alterations. No evidence of microvascular injury through whole experimental groups indicated that microvascular impairment does not contribute to early salivary gland injury.

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Phycocyanin alleviates alcohol-induced testicular injury in male Wistar rats

  • Oumayma Boukari;Soumaya Ghoghbane;Wahid Khemissi;Thalja Lassili;Olfa Tebourbi;Khemais Ben Rhouma;Mohsen Sakly;Dorsaf Hallegue
    • Clinical and Experimental Reproductive Medicine
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    • v.51 no.2
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    • pp.102-111
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    • 2024
  • Objective: Given the noteworthy implications of alcohol consumption and its association with male infertility, there has been a notable focus on investigating natural alternatives to mitigate its adverse effects. Thus, this study was conducted to assess the potential protective effect of phycocyanin extract derived from the blue algae Arthrospira (Spirulina) platensis against ethanol-induced oxidative stress, disturbances in testicular morphology, and alterations in sperm production. Methods: Male rats were divided into four groups (five rats each): the control group received a saline solution, the ethanol exposed group (EtOH) was subjected to intraperitoneal injections of 10 mL/kg of ethanol solution at a concentration of 38% (v/v), the phycocyanin alone treated group (P) received oral administration of phycocyanin at a dosage of 50 mg/kg, and the phycocyanin-cotreated group (PE) was given oral phycocyanin followed by ethanol injections. All treatments were administered over a period of 14 days. Results: Our findings demonstrated that ethanol exposure induced reproductive toxicity, characterized by reduced sperm production and viability, alterations in testicular weight and morphology, increased lipid peroxidation levels, and elevated oxidative enzyme activity. In addition, the ethanol-intoxicated group showed perturbations in serum biochemical parameters. However, the simultaneous exposure to ethanol and phycocyanin exhibited a counteractive effect against ethanol toxicity. Conclusion: The results showed that supplementation of phycocyanin prevented oxidative and testicular morphological damage-induced by ethanol and maintained normal sperm production, and viability.

Inhibition of Hypoxia-induced Apoptosis in PC12 Cells by Estradiol

  • Jung, Ji-Yeon;Roh, Kwang-Hoon;Jeong, Yeon-Jin;Kim, Sun-Hun;Lee, Eun-Ju;Kim, Min-Seok;Oh, Won-Mann;Oh, Hee-Kyun;Kim, Won-Jae
    • The Korean Journal of Physiology and Pharmacology
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    • v.9 no.4
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    • pp.231-238
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    • 2005
  • Neuronal apoptotic events, which result in cell death, are occurred in hypoxic/ischemic conditions. Estradiol is a female sex hormone with steroid structure known to provide neuroprotection through multiple mechanisms in the central nervous system. This study was aimed to investigate the signal transduction pathway of $CoCl_2$-induced neuronal cell death and the inhibitory effects of estradiol. Administration of $CoCl_2$ decreased cell viability in both a dose- and time-dependent manner in PC12 cells. $CoCl_2$-induced cell death produced genomic DNA fragmentation and morphologic changes such as cell shrinkage and condensed nuclei. It was found that $CoCl_2$-treated cells increased the reactive oxygen species (ROS) as well as caspase-8, -9 and -3 activities. However, pretreatment with estradiol before exposure to $CoCl_2$ prevented the reduction in cell viability reduction and attenuated DNA fragmentation and morphologic changes caused by $CoCl_2$. Furthermore, the $CoCl_2$-induced increases of ROS levels and caspases activities were attenuated by estradiol. Gene expression analysis revealed that estradiol blocked the underexpression of the Bcl-2 and ameliorated the increase in the release of cytochrome c from mitochondria into cytoplasm and Fas-ligand (Fas-L) upregulated by $CoCl_2$. These results suggest that $CoCl_2$ induce apoptosis in PC12 cells through both mitochondria- and death receptor-mediated cell death pathway. Estradiol was found to have a neuroprotective effect against $CoCl_2$-induced apoptosis through the inhibition of ROS production and by modulating apoptotic effectors associated with the mitochondria- and death-dependent pathway in PC12 cells.

Maxillary reconstruction using tunneling flap technique with 3D custom-made titanium mesh plate and particulate cancellous bone and marrow graft: a case report

  • Takano, Masayuki;Sugahara, Keisuke;Koyachi, Masahide;Odaka, Kento;Matsunaga, Satoru;Homma, Shinya;Abe, Shinichi;Katakura, Akira;Shibahara, Takahiko
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.41
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    • pp.43.1-43.5
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    • 2019
  • Background: Reconstructive surgery is often required for tumors of the oral and maxillofacial region, irrespective of whether they are benign or malignant, the area involved, and the tumor size. Recently, three-dimensional (3D) models are increasingly used in reconstructive surgery. However, these models have rarely been adapted for the fabrication of custom-made reconstruction materials. In this report, we present a case of maxillary reconstruction using a laboratory-engineered, custom-made mesh plate from a 3D model. Case presentation: The patient was a 56-year-old female, who had undergone maxillary resection in 2011 for intraoral squamous cell carcinoma that presented as a swelling of the anterior maxillary gingiva. Five years later, there was no recurrence of the malignant tumor and a maxillary reconstruction was planned. Computed tomography (CT) revealed a large bony defect in the dental-alveolar area of the anterior maxilla. Using the CT data, a 3D model of the maxilla was prepared, and the site of reconstruction determined. A custom-made mesh plate was fabricated using the 3D model (Okada Medical Supply, Tokyo, Japan). We performed the reconstruction using the custom-made titanium mesh plate and the particulate cancellous bone and marrow graft from her iliac bone. We employed the tunneling flap technique without alveolar crest incision, to prevent surgical wound dehiscence, mesh exposure, and alveolar bone loss. Ten months later, three dental implants were inserted in the graft. Before the final crown setting, we performed a gingivoplasty with palate mucosal graft. The patient has expressed total satisfaction with both the functional and esthetic outcomes of the procedure. Conclusion: We have successfully performed a maxillary and dental reconstruction using a custom-made, pre-bent titanium mesh plate.

Three-dimensional image analysis of the skull using variable CT scanning protocols-effect of slice thickness on measurement in the three-dimensional CT images (두개골의 3차원 영상 분석을 위한 전산화단층촬영 방법의 비교-상층 두께가 3차원 영상의 계측에 미치는 영향)

  • Jeong Ho-Gul;Kim Kee-Deog;Park Hyok;Kim Dong-Ook;Jeong Haijo;Kim Hee-Joung;Yoo Sun Koo;Kim Yong Oock;Park Chang-Seo
    • Imaging Science in Dentistry
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    • v.34 no.3
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    • pp.151-157
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    • 2004
  • Purpose : To evaluate the quantitative accuracy of three-dimensional (3D) images by means of comparing distance measurements on the 3D images with direct measurements of dry human skull according to slice thickness and scanning modes. Materials and Mathods : An observer directly measured the distance of 21 line items between 12 orthodontic landmarks on the skull surface using a digital vernier caliper and each was repeated five times. The dry human skull was scanned with a Helical CT with various slice thickness (3, 5, 7 mm) and acquisition modes (Conventional and Helical). The same observer measured corresponding distance of the same items on reconstructed 3D images with the internal program of V-works 4.0/sup TM/(Cybermed Inc., Seoul, Korea). The quantitative accuracy of distance measurements were statistically evaluated with Wilcoxons' two-sample test. Results: 11 line items in Conventional 3 mm, 8 in Helical 3mm, 11 in Conventional 5mm, 10 in Helical 5mm, 5 in Conventional 7mm and 9 in Helical 7mm showed no statistically significant difference. Average difference between direct measurements and measurements on 3D CT images was within 2mm in 19 line items of Conventional 3mm, 20 of Helical 3mm, 15 of Conventional 5mm, 18 of Helical 5mm, II of Conventional 7mm and 16 of Helical 7mm. Conclusion: Considering image quality and patient's exposure time, scanning protocol of Helical 5mm is recommended for 3D image analysis of the skull in CT.

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A dose monitoring system for dental radiography

  • Lee, Chena;Lee, Sam-Sun;Kim, Jo-Eun;Symkhampha, Khanthaly;Lee, Woo-Jin;Huh, Kyung-Hoe;Yi, Won-Jin;Heo, Min-Suk;Choi, Soon-Chul;Yeom, Heon-Young
    • Imaging Science in Dentistry
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    • v.46 no.2
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    • pp.103-108
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    • 2016
  • Purpose: The current study investigates the feasibility of a platform for a nationwide dose monitoring system for dental radiography. The essential elements for an unerring system are also assessed. Materials and Methods: An intraoral radiographic machine with 14 X-ray generators and five sensors, 45 panoramic radiographic machines, and 23 cone-beam computed tomography (CBCT) models used in Korean dental clinics were surveyed to investigate the type of dose report. A main server for storing the dose data from each radiographic machine was prepared. The dose report transfer pathways from the radiographic machine to the main sever were constructed. An effective dose calculation method was created based on the machine specifications and the exposure parameters of three intraoral radiographic machines, five panoramic radiographic machines, and four CBCTs. A viewing system was developed for both dentists and patients to view the calculated effective dose. Each procedure and the main server were integrated into one system. Results: The dose data from each type of radiographic machine was successfully transferred to the main server and converted into an effective dose. The effective dose stored in the main server is automatically connected to a viewing program for dentist and patient access. Conclusion: A patient radiation dose monitoring system is feasible for dental clinics. Future research in cooperation with clinicians, industry, and radiologists is needed to ensure format convertibility for an efficient dose monitoring system to monitor unexpected radiation dose.