Programmed cellular response to ionizing radiation damage

Typically, economic evaluation compares the costs and benefits of two or more interventions and seeks to identify the single superior option on the basis of relative cost-effectiveness. It is then anticipated that all patients will receive the more or most cost-effective option. This 'all or nothing' approach can be departed from when sub-groups of patient exist, defined on the basis of clinical or demographic characteristics which are considered to influence benefit, for whom an option is cost-effective whilst not being so for the population of patients as a whole. However, patients' preferences concerning the different process characteristics and outcomes of an intervention will also influence the benefit they derive from health care. This paper explores the concept of preference-based sub-group analysis in economic evaluation to assess the potential cost-effectiveness of using patients' preferences to determine treatment allocation. The clinical example used to explore these methods is the comparison of abdominal hysterectomy (AH) and transcervical resection of the endometrial (TCRE) for the treatment of menorrhagia.     

Solar ultraviolet radiation and skin damage: an epidemiological study among a Chinese population

In the last 20 years the treatment results of testicular cancer has been improved. At the present time up to 90% of patients are cured. Following successful treatment young men want to assess their fertility and possibility to have children. 18 men with testicular cancer has been treated in Institute of Oncology in Warsaw. Before and/or after orchidectomy semen analysis and assessment of serum levels of FSH, LH, testosterone has been performed. The quality of the semen is much worse in the group with cancer compared to healthy controls. Semen analysis following orchidectomy revealed that spermatozoa count did not change, FSH, LH levels increased and testosterone level decreased.     

Measurement of DNA damage after exposure to 2450 MHz electromagnetic radiation

Recent reports suggest that exposure to 2450 MHz electromagnetic radiation causes DNA single-strand breaks (SSBs) and double-strand breaks (DSBs) in cells of rat brain irradiated in vivo (Lai and Singh, Bioelectromagnetics 16, 207-210, 1995; Int. J. Radiat. Biol. 69, 513-521, 1996). Therefore, we endeavored to determine if exposure of cultured mammalian cells in vitro to 2450 MHz radiation causes DNA damage. The alkaline comet assay (single-cell gel electrophoresis), which is reportedly the most sensitive method to assay DNA damage in individual cells, was used to measure DNA damage after in vitro 2450 MHz irradiation. Exponentially growing U87MG and C3H 10T1/2 cells were exposed to 2450 MHz continuous-wave (CW) radiation in specially designed radial transmission lines (RTLs) that provided relatively uniform microwave exposure. Specific absorption rates (SARs) were calculated to be 0.7 and 1.9 W/kg. Temperatures in the RTLs were measured in real time and were maintained at 37 +/- 0.3 degrees C. Every experiment included sham exposure(s) in an RTL. Cells were irradiated for 2 h, 2 h followed by a 4-h incubation at 37 degrees C in an incubator, 4 h and 24 h. After these treatments samples were subjected to the alkaline comet assay as described by Olive et al. (Exp. Cell Res. 198, 259-267, 1992). Images of comets were digitized and analyzed using a PC-based image analysis system, and the "normalized comet moment" and "comet length" were determined. No significant differences were observed between the test group and the controls after exposure to 2450 MHz CW irradiation. Thus 2450 MHz irradiation does not appear to cause DNA damage in cultured mammalian cells under these exposure conditions as measured by this assay.     

The emerging Hispanic population: a foundation for cancer prevention and control

Although making up only 9% of the U.S. population and concentrated in urban areas of a few states, Hispanics are found throughout the country and represent a mix of historical and cultural backgrounds. This diverse group cuts across racial and ethnic lines, with origins in various countries of Europe and North, Central, and South America. The Hispanic population has several distinguishing demographic characteristics, including its rapid growth rate, relative youth, and low educational and socioeconomic levels. However, considerable differences exist among Hispanic groups, particularly in median age, household size, education, and family income. The majority of Hispanics face barriers to health care access, including a lack of health insurance coverage, underrepresentation in health care fields, and cultural and language differences. These distinct demographic characteristics and barriers have a direct impact on the risk of cancer in Hispanics and on the development of prevention and control strategies. The purpose of this review is to examine the demographic and socioeconomic characteristics of Hispanics and issues of access to health care among this population within the context of cancer prevention and control.     

应用激光多普勒测振仪的岩块体累计损伤评价试验研究

岩块体崩塌破坏的突发性使其成为最难预防的地质灾害,严重威胁人类的生命财产安全.边坡岩块体崩塌破坏多是系统不稳定导致的动力破坏,而用振动特征参数来进行安全监测和损伤评价更为有效.本文应用激光多普勒测振技术,通过固有振动频率对危岩块体主控结构面的黏结力损伤进行定量分析.通过改进后的极限平衡模型,得出结构面不断劣化块体的安全系数由原来的1.17下降到1.04,与实际破坏结果相符.试验结果表明：固有振动频率一方面可对危岩块体累积损伤进行有效识别,另一方面可以为黏结力参数的合理确定提供客观的数据支持.因此,基于固有振动频率分析的激光多普勒测振技术可实现边坡岩块体的累计损伤评价,并将在未来的工程应用中发挥巨大的作用.     

Assessment of skin types, skin colours and cutaneous responses to ultraviolet radiation in an Asian population

Ninety normal individuals were included in this study on skin types, skin colours and cutaneous responses to ultraviolet radiation. Skin types were recorded using Fitzpatrick's classification, skin colours were measured using the Minolta Chromameter CR-300, and cutaneous responses to UV radiation were measured in terms of minimal erythema dose (MED) to UVA, UVB and the immediate pigment darkening dose to UVA (IPDDA). Skin colour measurements were taken from the right cheek to represent facultative skin colours, and from the buttock to represent constitutive skin colours. The colours measured were expressed by the L x a x b colour space. Skin types and some colour parameters (L and b from covered parts of body) correlated fairly well with the minimal erythema doses (MED) to UVA and UVB. Skin colour measurements are more objective than skin type assessment and could be better markers of photosensitivity. However, there is still considerable overlap in MEDs for persons with different skin colours, and further studies of these parameters are warranted. Our MEDs are higher than other reports on similar skin types and skin colours. This could be due to differences in methodology, genetic make-up or acclimatization from chronic sun exposure. This illustrates the importance of local controls for each institution dealing with photosensitive disorders.     

Analytical electron microscopy studies of radiation damage

Analytical electron microscopy (AEM) has provided structural, crystallographic, and compositional characterization to aid in the understanding of radiation damage processes, especially in multiphase materials. The range of AEM techniques is based on the use of as many of the signals produced by the interaction of an electron beam with a specimen as possible. This paper briefly discusses the origins, capabilities, and current developments of AEM, including the spatial resolution of the various techniques. Several important applications of AEM in radiation damage studies, including radiation-induced segregation and phase instability in austenitic stainless steels, will be reviewed. From the comparison of phase equilibria under irradiation to that under thermal aging, principles for alloy development in non-nuclear applications will be discussed. This paper is based on a presentation made in the symposium “Irradiation-Enhanced Materials Science and Engineering” presented as part of the ASM INTERNATIONAL 75th Anniversary celebration at the 1988 World Materials Congress in Chicago, IL, September 25-29, 1988, under the auspices of the Nuclear Materials Committee of TMS-AIME and ASM-MSD.     

Effect of ATP on radiation damage to DNA caused by prolonged irradiation

The influence of bradykinin and kallikrein on the action of norepinephrine, epinephrine, isoprenaline, phentolamine, propranolol, aminophylline and theophylline on blood pressure was studied. The kinins potentiated the hypertensive action of norepinephrine and epinephrine, weakened the hypotensive action of isoprenaline, potentiated the hypotensive action of propranolol, and had no effect on the action of phentolamine, aminophylline and theophylline.     

The prevention of inflammatory complications in mandibular fractures by using infrared laser and magnetic-laser radiation

Nurses and physicians practice and think differently and, as a result, the information systems they use are different. But managed care and the things it brings with it--care teams, cost control, outcomes management and the move from a "Medical Model" to a "Wellness Model"--is closing the gap between the two. This article examines some of the traditional differences between the two disciplines and the problems these differences present, as well as shared expertise, how managed care is contributing to this overlap and how information systems are evolving to support the new synergies.     

大型预焙电解槽破损原因浅析

对大型预焙槽内衬破损的现象进行分析,寻求预防电解槽破损的方法,指出延长电解槽寿命的关键在于电解槽的平稳生产。     

大型预焙电解槽破损原因浅析

对大型预焙槽内衬破损的现象进行分析，寻求预防电解槽破损的方法，指出延长电解槽寿命的关键在于电解槽的平稳生产。     

Real-time measurement of skin radiation during cardiac catheterization

A novel skin dose monitor was used to measure radiation incident on maximal X-ray exposed skin during 135 diagnostic and 65 interventional coronary procedures. For the diagnostic studies (n = 135), mean skin dose was 180 +/- 64 mGy; for PTCA (n = 35), it was 1021 +/- 674 mGy, single stents (n = 25) 1529 +/- 601 mGy, and multiple stents with rotational atherectomy (n = 5) 2496 +/- 1028 mGy. The dose independently increased with more cine runs, more fluoroscopy, and greater patient weight. Physicians should consider the potential for adverse radiation exposure when planning coronary interventional cases and deciding on the X-ray mode and angles used.     

Gabexate for the prevention of pancreatic damage related to endoscopic retrograde cholangiopancreatography. Gabexate in digestive endoscopy--Italian Group

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is associated with elevated levels of pancreatic enzymes and pancreatitis. Gabexate, a protease inhibitor, has been used to prevent pancreatic damage related to ERCP. METHODS: We conducted a multicenter, double-blind comparison of gabexate (1 g given by intravenous infusion starting 30 to 90 minutes before endoscopy and continuing for 12 hours afterward) with placebo (mannitol and sodium chloride, administered in the same fashion). A total of 435 adults scheduled to undergo ERCP and, when indicated, endoscopic sphincterotomy underwent randomization; 17 were excluded from the final analysis for various reasons. The remaining 418 patients (mean age, 60.4 years)--208 in the gabexate group and 210 in the placebo group--were analyzed. Acute pancreatitis was considered to be present if serum amylase or lipase levels (or both) were five times greater than the upper limits of normal in association with the onset of pancreatic pain. RESULTS: After the procedures, 276 patients (66 percent) had elevated pancreatic-enzyme levels; the frequency was similar in the two groups. Mean serum amylase values were higher in the placebo group than in the gabexate group through 24 hours of observation (P=0.03). Twelve patients in the gabexate group and 29 in the placebo group had abdominal pain (6 percent vs. 14 percent, P=0.009). Sixteen patients in the placebo group and five in the gabexate group had acute pancreatitis (8 percent vs. 2 percent, P=0.03). Two patients treated with gabexate and six given placebo had adverse events, all of which resolved. Two patients given placebo died of acute pancreatitis; one was excluded from the evaluation because pancreatitis was present before endoscopy. One patient in the gabexate group died, from a myocardial infarction. CONCLUSION: Prophylactic treatment with gabexate reduced pancreatic damage related to ERCP, as reflected by reductions in the extent but not the frequency of elevated enzyme levels and in the frequency of pancreatic pain and acute pancreatitis.