• 제목/요약/키워드: Health Risk Factor

검색결과 1,475건 처리시간 0.034초

Hormesis as a Confounding Factor in Epidemiological Studies of Radiation Carcinogenesis

  • Sanders Charles L.
    • Journal of Radiation Protection and Research
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    • 제31권2호
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    • pp.69-89
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    • 2006
  • Biological mechanisms for ionizing radiation effects are different at low doses than at high doses. Radiation hormesis involves low-dose-induced protection and high-dose-induced harm. The protective component is associated with a reduction in the incidence of cancer below the spontaneous frequency, brought about by activation of defensive and repair processes. The Linear No-Threshold (LNT) hypothesis advocated by the International Commission on Radiological Protection (ICRP) and the Biological Effects of ionizing Radiation (BEIR) Report VII for cancer risk estimations Ignores hormesis and the presence of a threshold. Cancer incidences significantly less than expected have been found in a large number of epidemiological studies including, airline flight personnel, inhabitants of high radiation backgrounds, shipyard workers, nuclear site workers in scores of locations throughout the world, nuclear power utility workers, plutonium workers, military nuclear test site Participants, Japanese A-bomb survivors, residents contaminated by major nuclear accidents, residents of Taiwan living in $^{60}Co$ contaminated buildings, fluoroscopy and mammography patients, radium dial painters, and those exposed to indoor radon. Significantly increased cancer was not found at doses <200 $mSv^*$. Evidence for radiation hormesis was seen in both sexes for acute or chronic exposures, low or high LET radiations, external whole- or partial body exposures, and for internal radionuclides. The ubiquitous nature of the Healthy Worker Effect (HWE)-like responses in cellular, animal and epidemiological studies negates the HWE as an explanation for radiation hormesis. The LNT hypothesis is wrong and does not represent the true nature of the dose-response relationship, since low doses or dose-rates commonly result in thresholds and reduce cancer incidences below the spontaneous rate. Radiation protection organizations should seriously consider the cost and health implications of radiation hormesis.

부분적 체중부하를 통한 트레드밀 훈련이 만성요통환자의 균형능력과 기능장애, 통증에 미치는 영향 (Effect of Partial Weight Supported Treadmill Training on Balance, Dysfunction and Pain in Patients With Chronic Low Back Pain)

  • 김대현;김선엽
    • 한국전문물리치료학회지
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    • 제23권1호
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    • pp.1-10
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    • 2016
  • Background: Patients with chronic low back pain (CLBP) functionally adapt to decreased postural control due to impaired processing of sensory information. Standing postural control has been the focus of recent research in CLBP. Change in postural control may be a risk factor for CLBP, although available studies are not conclusive. Objects: This study aimed to identify the role of partial weight supported treadmill training (PWSTT) in improving balance, dysfunction, and pain in patients with chronic low back pain. Methods: The study included 22 patients with CLBP. Patients in the control group ($n_1=8$) performed three 20 min stabilization exercise sessions per week, for 4 weeks. Patients in the full weight treadmill training group ($n_2=7$) performed treadmill training for 30 min after stabilization exercise. Patients in the PWSTT group ($n_3=7$) performed PWSTT with 20% of their body weight unloaded after stabilization exercises. By using the Biodex balance system, the dynamic balance abilities of the patients in the three groups were assessed in the quiet standing position under combined conditions of visual feedback (eyes open and closed) and platform stability (level 8). The Korean version of the Oswestry Disability Index and visual analogue scale score were used as the main measure. Results: The results of this study showed that dysfunction and pain were significantly improved in all groups. Although dynamic postural stability with eyes closed was significantly improved only in the PWSTT group (p<.05), no significant difference was found in the other groups. Conclusion: The results of this study indicate that PWSTT improved balance, dysfunction and pain in the patients with CLBP. Thus, this intervention is necessary for patients with CLBP with decreased postural control.

Angiographic and Clinical Factors Related with Good Functional Outcome after Mechanical Thrombectomy in Acute Cerebral Artery Occlusion

  • Park, Jong Hyuk;Han, Young Min;Jang, Kyeong Sool;Yoon, Wan Soo;Jang, Dong Kyu;Park, Sang Kyu
    • Journal of Korean Neurosurgical Society
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    • 제58권3호
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    • pp.192-196
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    • 2015
  • Objective : The aim of this study is to investigate good prognostic factors for an acute occlusion of a major cerebral artery using mechanical thrombectomy. Methods : Between January 2013 to December 2014, 37 consecutive patients with acute occlusion of a major cerebral artery treated by mechanical thrombectomy with stent retrievers were conducted. We analyzed clinical and angiographic factors retrospectively. The collateral flow and the result of recanalization were sorted by grading systems. Outcome was assessed by National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) at 90 days. We compared the various parameters between good and poor angiographic and clinical results. Results : Twenty seven patients demonstrated good recanalization [Thrombolysis in Cerebral Infarction (TICI) 2b or 3] after thrombectomy. At the 90-day follow up, 19 patients had good (mRS, 0-2), 14 had moderate (3-4) and four had poor outcomes (5-6). The mRS of older patients (${\geq}75years$) were poor than younger patients. Early recanalization, high Thrombolysis in Myocardial Infarction risk score, and low baseline NIHSS were closely related to 90-day mRS, whereas high TICI was related to both mRS and the decrease in the NIHSS. Conclusion : NIHSS decreased markedly only when recanalization was successful. A good mRS was related to low initial NIHSS, good collateral, and early successful recanalization.

일부 남녀 대학생에서 혈장 호모시스테인 농도와 산화 스트레스 지표와의 상관관계 (Relationships of Plasma Homocysteine Concentration and Oxidative Stress Markers in Korean Collage Students)

  • 김정신;박은주;민혜선;강명희
    • Journal of Nutrition and Health
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    • 제43권5호
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    • pp.443-452
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    • 2010
  • Elevated plasma concentration of total homocysteine (ptHcy) is known as an independent risk factor of cardiovascular disease (CVD) and oxidative stress is also commonly implicated in CVD. An association between ptHcy and oxidative stress has recently been suggested. The study objective is to examine the relationship between ptHcy and oxidative stress markers in 103 healthy college students (62 males and 41 females). Plasma levels of ptHcy, oxidative stress markers (conjugated diene, erythrocyte catalase, TRAP, lymphocyte DNA damage), antioxidant vitamins ($\alpha$-tocopherol, $\gamma$-tocopherol, carotenoids), and lipid parameters (total cholesterol, triglyceride, HDL cholesterol) were determined. The results show that the concentration of ptHcy was significantly higher in male subjects ($22.17\;{\pm}\;2.14\;{\mu}mole/L$) than in female subjects ($12.28\;{\pm}\;0.45\;{\mu}mole/L$). There was a negative association between ptHcy and plasma ${\beta}$-carotene in male subjects (p $lt; 0.05), but no correlation between ptHcy and other plasma antioxidant vitamin levels in either gender. However, there were the negative correlations between ptHcy and plasma ${\alpha}$-carotene or ${\beta}$-carotene, and a positive correlation between ptHcy and lymphocyte DNA damage. A significantly low level of ${\alpha}$-carotene or ${\beta}$-carotene was found in male subjects with elevated ptHcy (${\geq}\;15\;{\mu}mol/L$), as compared to those with lower plasma homocysteine. These study results confirmed the views on the association between plasma homocysteine and oxidative stress markers in humans and support the hypothesis that homocysteine promotes the oxidative environment by counteracting the antioxidant defense mechanism.

Identification of Transition Characteristics and Bio-concentration Factors of Heavy Metal (loid)s in the Selected Perennial Root Medicinal Plants

  • Kim, Won-Il;Noh, Hyun Myung;Hong, Chang-Oh;Kim, Da-Young;Kim, Kwon-Rae;Oh, Kyeong-Seok;Moon, Byeong-Churl;Kim, Ji-Young
    • 한국토양비료학회지
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    • 제50권4호
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    • pp.251-258
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    • 2017
  • This study was conducted to identify transition characteristics of arsenic (As), cadmium (Cd), and lead (Pb) and to calculate bio-concentration factors (BCF) in the three perennial root medicinal plants, namely Codonopsis lanceolata (Deoduck), Platycodon grandiflorum (Balloon flower) and Panax ginseng (Korean ginseng) grown in major medicinal plant producing districts in Korea. Average BCF values ranged from 0.009~0.029 in As, 0.334~1.453 in Cd, and 0.021~0.023 in Pb in three perennial root medicinal plants. The BCF values increased in the order of ginseng (0.029) > deodeok (0.012) > balloon flower (0.009) for As, balloon flower (1.453) > deodeok (0.685) > ginseng (0.334) for Cd, and ginseng (0.023) > deodeok (0.022) > balloon flower (0.021) for Pb. The BCF values calculated in this study will be useful for predicting the uptake of heavy metal (loid)s. Further study on uptake and accumulation mechanism of toxic metal (loid)s by agricultural products is required to assess the human health risk associated with soil contamination.

Aldosterone 유도체-고혈압의 음성적 유해와 은침점전기자극의 aldosterone 억제 (Negative noxiousness of aldosterone analogue-induced hypertension and inhibition of aldosterone by silver spike point electrical stimulation)

  • 천기영;김중환;김순희;민경옥
    • 대한물리치료과학회지
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    • 제10권2호
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    • pp.199-207
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    • 2003
  • The present study examined that in vivo/vitro test is investigated in normotensive sham-operated rats(NSR) and aldosterone-analogue deoxycorticosterone acetate (DOCA)-salt hypertensive rats(ADHR) and that the antiliypertensive effect was induced by silver spike point(SSP) electrical stimulation at meridian points(CV-3, -4, Ki-12, SP-6, LR-3, BL-25, -28, -32, -52), specifically, such as aldosterone in 24 hour urine analysis from normal volunteer. The heart weight, the tickness of vascular wall, collagen fiber and the systolic blood pressure were significantly increased in ADHR than that in NSR. The required time of PSS-induced resting tone and the phosphorylation of stress-activated protein kinase/c-Jun N-terminal protein kinase(SAPK/JNK) were significantly increased in ADHR than that in NSR. However, the Kv currents were significantly decreased in ADHR than that in NSR. The current of 1 Hz continue type of SSP electrical stimulation significantly decreased in excretion of urine aldosterone from normal volunteer. These results suggest that the development of aldosterone analogue-induced hypertension is associated with changed heart weight, content of collagen fiber, tickness of vascular wall, blood pressure, resting tone, voltage-dependent K+ current(Kv) and phosphorylation of SAPK/JNK, which directly affects blood pressure. Therefore the hypertension is a risk factor on cerebrovascular disease. Moreover, These results suggest that the SSP electrical stimulation, especially current of 1 Hz continue type, significantly regulates excretion of urine aldosterone from volunteer.

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쥐에서 식이 Calcium이 대장 암화관정의 세포증식과 대장점막의 Eicosanoid 및 1,2 -diacylglycerol 수준에 미치는 영향 (Effect of Dietary Calcium on Cell Proliferation and Colonic Mucosal Levels of Eicosanoid and 1,2-diacylglycerol in Colon Carcinogenesis of Rats)

  • 김채종
    • Journal of Nutrition and Health
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    • 제31권1호
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    • pp.21-27
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    • 1998
  • The objective of this study was to observe the effect of dietary calcium(Ca) level on colonic mucosal levels of cell proliferation, 1, 2-diacylglycerol(DAG), TXB2, PGE2 and phospholipid fatty acid composition which have been known as biomarkers for colon cancer. One hundred male Sprague Dawley rats, at 7 weeks of age, were divided into two fat type groups. Each group of which was further divided into two Ca level groups. Each rt was intramuscularly injected with 1, 2,-dimenthylhydrazine(DMH) for 6 weeks (total dose of 180mg/kg body weight) and simultaneously fed one of four experimental diets containing 15% dietary fat(corn oil or perilla oil )and 0.3% or 1.0% Ca by weight for 20 weeks. Compared to corn oil, perilla oil significantly reduced cell proliferation by decreasing labeling index, proliferating zone, crypt length in colonic mucosa and colonic mucosa and colonic mucosal levels of DAG, TXB2 . PGE2 and phospolipid (PL) arachidonic acid distribution. The effect of Ca on biomarketrs was different depending on the type of dietary fat comsumed . Ca effect of Ca on biomarkers was different depending on the type of dietary fat comsumed. Ca effect was not significantly shown in the PO group, but it was significant in the CO group in which high Ca(1.0%) decreased the levels of levels of PL-C20 : 4(%), DAG and PGE2 . However , high Ca supplementation had shown only the trends of improving cell proliferation. Overall , high dietary Ca significantly reduced cell proliferation by inhibiting the synthesis of eicosanoid and DAG with reduced distribution of PL-C20 : 4 , which may have resulted in lower activation of PKC through reduced signal transduction. Since a high level of dietary Ca was more effective in reducing the risk factor against colon cancer in corn oil fed rats, it could be suggested that a higher amount of dietary Ca be consumed , especially when more vegetable oil rich in linoleic acid is included in the diet.

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Is catechol-o-methyltransferase gene polymorphism a risk factor in the development of premenstrual syndrome?

  • Deveci, Esma Ozturk;Incebiyik, Adnan;Selek, Salih;Camuzcuoglu, Aysun;Hilali, Nese Gul;Camuzcuoglu, Hakan;Erdal, Mehmet Emin;Vural, Mehmet
    • Clinical and Experimental Reproductive Medicine
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    • 제41권2호
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    • pp.62-67
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    • 2014
  • Objective: The objective of this study was to investigate whether there was a correlation between catechol-o-methyltransferase (COMT) gene polymorphism, which is believed to play a role in the etiology of psychotic disorders, and premenstrual syndrome (PMS). Methods: Fifty-three women with regular menstrual cycles, aged between 18 and 46 years and diagnosed with PMS according to the American Congress of Obstetrics and Gynecology criteria were included in this study as the study group, and 53 healthy women having no health problems were selected as the controls. Venous blood was collected from all patients included in the study and kept at $-18^{\circ}C$ prior to analysis. Results: There was no significant difference between the groups in terms of demographic features such as age, body mass index, number of pregnancies, parity, and number of children. No statistically significant difference was observed in terms of COMT gene polymorphism (p=0.61) between women in the PMS and the control groups. However, a significant difference was found between arthralgia, which is an indicator of PMS, and low-enzyme activity COMT gene (Met/Met) polymorphism (p=0.04). Conclusion: These results suggested that there was no significant relationship between PMS and COMT gene polymorphism. Since we could not find a direct correlation between the COMT gene polymorphism and PMS, further studies including alternative neurotransmitter pathways are needed to find an effective treatment for this disease.

교대근무 간호사의 혈액과 체액 노출 사고 예측 요인과 감염예방행위의 매개효과: 영과잉 가산 자료 분석방법을 적용하여 (Predictors of Blood and Body Fluid Exposure and Mediating Effects of Infection Prevention Behavior in Shift-Working Nurses: Application of Analysis Method for Zero-Inflated Count Data)

  • 류재금;최스미
    • 대한간호학회지
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    • 제50권5호
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    • pp.658-670
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    • 2020
  • Purpose: This study aimed to identify the predictors of blood and body fluid exposure (BBFE) in multifaceted individual (sleep disturbance and fatigue), occupational (occupational stress), and organizational (hospital safety climate) factors, as well as infection prevention behavior. We also aimed to test the mediating effect of infection prevention behavior in relation to multifaceted factors and the frequency of BBFE. Methods: This study was based on a secondary data analysis, using data of 246 nurses from the Shift Work Nurses' Health and Turnover study. Based on the characteristics of zero-inflated and over-dispersed count data of frequencies of BBFE, the data were analyzed to calculate zero-inflated negative binomial regression within a generalized linear model and to test the mediating effect using SPSS 25.0, Stata 14.1, and PROCESS macro. Results: We found that the frequency of BBFE increased in subjects with disturbed sleep (IRR = 1.87, p = .049), and the probability of non-BBFE increased in subjects showing higher infection prevention behavior (IRR = 15.05, p = .006) and a hospital safety climate (IRR = 28.46, p = .018). We also found that infection prevention behavior had mediating effects on the occupational stress-BBFE and hospital safety climate-BBFE relationships. Conclusion: Sleep disturbance is an important risk factor related to frequency of BBFE, whereas preventive factors are infection prevention behavior and hospital safety climate. We suggest individual and systemic efforts to improve sleep, occupational stress, and hospital safety climate to prevent BBFE occurrence.

성상신경절차단술로 제어되지 않은 대상포진후 신경통환자 치험 1예 (A Case Report of Post-herpetic neuralgia uncontroled after Stellate Ganglion Block)

  • 이정은;배한호;한영주;임도희;채은영;조철준;박양춘
    • 대한한방내과학회지
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    • 제25권3호
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    • pp.669-676
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    • 2004
  • Post-herpetic neuralgia(PHN) is a chronic pain syndrome associated with the reactivation of a primary infection with varicella zoster virus(chinken pox), which leads to a chronic infection of dorsal root ganglia. The most common risk factor for shingles and its potential sequela, PHN, is advanced age. For a significant number of patients, the pain following healing of shingles can persist for months to years. If this pain, classified as PHN, persists longer than one month. PHN often leads to depression, disrupted sleep, decreased productivity, and utilization of health care. We treated a 60 year-old female patient who suffered pain and headache after Stellate Ganglion Blocks(SGB). In identifying points for differentiation of syndrom(辨證), this subject was diagnosed as Yangmyeong Merdian wind-heat syndrom(陽明經風熱證) and was administered Seungmagalgeuntanggamibang(revised Shengmagalgen-tang, 升麻葛根湯加味方). To ease pain, Western medication was administered as well. After fourteen days of treatment, pain and other symptoms improved.

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