Effects of a wireless local area network (LAN) system, a telemetry system, and electrosurgical devices on medical devices in a hospital environment

Concerns have been raised about interference of wireless local area network (LAN) systems and telemetry systems with medical devices in hospitals. The authors have investigated the susceptibility of 65 electromedical devices to a wireless LAN system and a telemetry system in preselected areas of a hospital. Testing was based on the American National Standards Institute Standard C63.18. The wireless LAN system operated at 2.42 GHz with an output power of 100 mW. The telemetry system operated at 466 MHz with an output power of 4 mW. Of the 65 devices tested, only two hand-held Doppler units, a Mini Doppler Model D900 (Huntleigh Healthcare Ltd) and a Ultrasonic Doppler Model 811 (Parks Medical Electronics, Inc.), were affected by the LAN system. Placed within 10 cm of the LAN system in standby mode, both units emitted periodic high-pitched beating sounds, which could be misinterpreted as normal beating sounds from the patient. These changed to random static noise during data transmission by the LAN. Under normal conditions of use, a LAN system would never be placed this close to a medical device. The quality of data transmission from the LAN system changed from "good" to "acceptable" in the colonoscopy room. This deterioration in transmission quality could have been caused by the lead shielding in the room. Electrosurgical devices operating at 0.5 to 1 MHz did not affect the LAN system at distances up to 3 m. None of the devices was affected by the telemetry system. These findings suggest that wireless LAN systems and telemetry systems can be acceptable for use in hospitals. Nevertheless, other systems should be tested on potentially susceptible devices by the hospital before use.     

Perinatal death recording: time for a change?

The new perinatal death certificate proposed by the World Health Organisation was examined in relation to existing measures for recording perinatal death statistics and also with regard to new information gathered. Present procedures appear to underestimate the number of perinatal deaths by roughly 10%, though late registrations may lower this figure slightly. The use of a minimum birth weight as the criterion for inclusion in perinatal statistics removed much of the uncertainty associated with definitions of live birth and stillbirth. The new certificate led to duplication of some information already recorded through birth notification yet failed to provide information on some other factors generally considered relevant to perinatal mortality. The format proposed for recording cause of death provided a more logical presentation of events. Standardizing birth information recorded on all infants, modifying death certificates, and developing efficient record-linkage schemes would be more valuable than introducing the WHO certificate. Useful interpretation of the meaning of the characteristics of infants dying in the perinatal period awaits these timely changes.     

Chronic exposure to dim light at night suppresses immune responses in Siberian hamsters

Species have been adapted to specific niches optimizing survival and reproduction; however, urbanization by humans has dramatically altered natural habitats. Artificial light at night (LAN), termed 'light pollution', is an often overlooked, yet increasing disruptor of habitats, which perturbs physiological processes that rely on precise light information. For example, LAN alters the timing of reproduction and activity in some species, which decreases the odds of successful breeding and increases the threat of predation for these individuals, leading to reduced fitness. LAN also suppresses immune function, an important proxy for survival. To investigate the impact of LAN in a species naive to light pollution in its native habitat, immune function was examined in Siberian hamsters derived from wild-caught stock. After four weeks exposure to dim LAN, immune responses to three different challenges were assessed: (i) delayed-type hypersensitivity (DTH), (ii) lipopolysaccharide-induced fever, and (iii) bactericide activity of blood. LAN suppressed DTH response and reduced bactericide activity of blood after lipopolysaccharide treatment, in addition to altering daily patterns of locomotor activity, suggesting that human encroachment on habitats via night-time lighting may inadvertently compromise immune function and ultimately fitness.     

Perinatal photoperiod organizes adult immune responses in Siberian hamsters (Phodopus sungorus)

Individuals of many nontropical rodent species display reproductive, immunological, and somatic responses to day length. In general, short day (SD) lengths inhibit reproduction and enhance immune function in the laboratory when all other conditions are held constant. Most studies to date have focused on seasonal variation in immune function in adulthood. However, perinatal photoperiods also communicate critical day length information and serve to establish a developmental trajectory appropriate for the time of year. Nontropical rodents born early in the breeding season undergo rapid reproductive development, presumably to promote mating success during their first reproductive season. Rodents born late in the breeding season suspend somatic growth and puberty until the following vernal breeding season. We tested the hypothesis that perinatal day lengths have similar enduring effects on the immune system of rodents. Siberian hamsters (Phodopus sungorus) were maintained prenatally and until weaning (21 days) in either SDs (8 h light:16 h dark) or long days (LD) (16 h light:8 h dark), then they were weaned into either the opposite photoperiod or maintained in their natal photoperiod, forming four groups (LD-LD, LD-SD, SD-LD, and SD-SD). After 8-wk in these conditions, cell-mediated immune activity was compared among groups. SD-SD hamsters of both sexes enhanced immune function relative to all other groups. The reproductive effects of perinatal photoperiod were not evident by the end of the experiment; circulating testosterone and cortisol sampled at the end of the experiment reflected the postweaning, but not the perinatal photoperiod. This experiment demonstrates long-lasting organizational effects of perinatal photoperiod on the rodent immune system and indicates that photoperiod-induced changes in the immune system are dissociable from changes in the reproductive system.     

Neural control of human motor development

It has been possible to expand considerably our understanding of human motor development by making a detailed analysis of various types of movement and muscular activation patterns during different stages of development. Alterations in development subsequent to the appearance of brain lesions have enabled valuable information to be collected about the underlying neural mechanisms, in addition to new information concerning the pathophysiology of cerebral palsy. Studies on the development of the corticospinal system indicate that plastic changes can take place after perinatal brain damage.     

Light at night co-distributes with incident breast but not lung cancer in the female population of Israel

Recent studies of shift-working women have reported that excessive exposure to light at night (LAN) may be a risk factor for breast cancer. However, no studies have yet attempted to examine the co-distribution of LAN and breast cancer incidence on a population level with the goal to assess the coherence of these earlier findings with population trends. Coherence is one of Hill's "criteria" (actually, viewpoints) for an inference of causality. Nighttime satellite images were used to estimate LAN levels in 147 communities in Israel. Multiple regression analysis was performed to investigate the association between LAN and breast cancer incidence rates and, as a test of the specificity of our method, lung cancer incidence rates in women across localities under the prediction of a link with breast cancer but not lung cancer. After adjusting for several variables available on a population level, such as ethnic makeup, birth rate, population density, and local income level, a strong positive association between LAN intensity and breast cancer rate was revealed (p<0.05), and this association strengthened (p<0.01) when only statistically significant factors were filtered out by stepwise regression analysis. Concurrently, no association was found between LAN intensity and lung cancer rate. These results provide coherence of the previously reported case-control and cohort studies with the co-distribution of LAN and breast cancer on a population basis. The analysis yielded an estimated 73% higher breast cancer incidence in the highest LAN exposed communities compared to the lowest LAN exposed communities.     

Light at Night Co‐distributes with Incident Breast but not Lung Cancer in the Female Population of Israel

Recent studies of shift‐working women have reported that excessive exposure to light at night (LAN) may be a risk factor for breast cancer. However, no studies have yet attempted to examine the co‐distribution of LAN and breast cancer incidence on a population level with the goal to assess the coherence of these earlier findings with population trends. Coherence is one of Hill's “criteria” (actually, viewpoints) for an inference of causality. Nighttime satellite images were used to estimate LAN levels in 147 communities in Israel. Multiple regression analysis was performed to investigate the association between LAN and breast cancer incidence rates and, as a test of the specificity of our method, lung cancer incidence rates in women across localities under the prediction of a link with breast cancer but not lung cancer. After adjusting for several variables available on a population level, such as ethnic makeup, birth rate, population density, and local income level, a strong positive association between LAN intensity and breast cancer rate was revealed (p<0.05), and this association strengthened (p<0.01) when only statistically significant factors were filtered out by stepwise regression analysis. Concurrently, no association was found between LAN intensity and lung cancer rate. These results provide coherence of the previously reported case‐control and cohort studies with the co‐distribution of LAN and breast cancer on a population basis. The analysis yielded an estimated 73% higher breast cancer incidence in the highest LAN exposed communities compared to the lowest LAN exposed communities.     

Perinatal olfactory learning in the domestic dog

The ability of individuals to learn about chemosensory stimuli in the prenatal, or immediate postnatal, period may be advantageous in acquiring information about "safe" foods after weaning. In this study, we examined the influence of perinatal exposure to aniseed via the mother's diet on a two-choice food test in the domestic dog. Pups were tested at 10 weeks of age following "prenatal" exposure to aniseed (the last 20 days of gestation), "postnatal" exposure to aniseed (the first 20 days after birth), "perinatal" exposure to aniseed (pre- and postnatal exposure combined), or no exposure to aniseed prenatally or postnatally (control). Perinatal exposure resulted in a significantly greater preference for the aniseed food than the other types of exposure. At 10 weeks, there was no evidence for the retention of any prenatal learning of the aniseed. It is suggested that exposure to a chemosensory stimulus across the perinatal period results in a greater effect than simply the sum of pre- and postnatal exposure due to priming of the chemosensory system via prenatal chemosensory experience. Such a system may confer survival advantages by promoting the acquisition of information about safe foods.     

Occupational magnetic field exposure and melatonin: interaction with light-at-night

The evidence of magnetic field (MF) effects on melatonin production in humans is limited and inconsistent. Part of the inconsistencies might be explained by findings suggesting interaction with light in pineal responses to MFs. To test this hypothesis, we reanalyzed data from a previously published study on 6-hydroxy melatonin sulfate (6-OHMS) excretion in women occupationally exposed to extremely low-frequency MFs. Based on questionnaire data on exposure to light-at-night (LAN), and measurement-based MF data, the 60 women were classified to four groups: no MF, no LAN; MF, no LAN; no MF, LAN; MF, LAN. The lowest excretion of 6-OHMS was observed in the group of women who were exposed to both MF and LAN, and the differences between the four groups were significant (P < .0001). The result is based on low numbers, but supports the hypothesis that daytime occupational exposure to MF enhances the effects of nighttime light exposure on melatonin production.     

Metabolic Implications of Exposure to Light at Night: Lessons from Animal and Human Studies

Lately, the incidence of overweight, obesity, and type 2 diabetes has shown a staggering increase. To prevent and treat these conditions, one must look at their etiology. As life on earth has evolved under the conditions of nature’s 24‐hour light/dark cycle, it seems likely that exposure to artificial light at night (LAN) would affect physiology. Indeed, ample evidence has shown that LAN impacts many metabolic parameters, at least partly via the biological clock in the suprachiasmatic nucleus of the hypothalamus. This review focuses on the impact of chronic and acute effects of LAN of different wavelengths on locomotor activity, food intake, the sleep/wake cycle, body temperature, melatonin, glucocorticoids, and glucose and lipid metabolism. While chronic LAN disturbs daily rhythms in these parameters, experiments using short‐term LAN exposure also have shown acute negative effects in metabolically active peripheral tissues. Experiments using LAN of different wavelengths not only have indicated an important role for melanopsin, the photopigment found in intrinsically photosensitive retinal ganglion cells, but also provided evidence that each wavelength may have a specific impact on energy metabolism. Importantly, exposure to LAN has been shown to impact glucose homeostasis also in humans and to be associated with an increased incidence of overweight, obesity, and atherosclerosis.     

Light at night and melatonin have opposite effects on breast cancer tumors in mice assessed by growth rates and global DNA methylation

Light-at-night (LAN) is a worldwide problem co-distributed with breast cancer prevalence. We hypothesized that exposure to LAN is coincided with a decreased melatonin (MLT) secretion level, followed by epigenetic modifications and resulted in higher breast cancer tumors growth-rate. Accordingly, we studied the effect of LAN exposure and exogenous MLT on breast cancer tumors growth-rate. 4T1 cells were inoculated into BALB/c short day-acclimated mice, resulting in tumors growth. Growth rates were followed under various light exposures and global DNA methylations were measured. Results demonstrated the positive effect of LAN on tumors growth-rate, reversed by MLT through global DNA methylation.     

Methods and models to determine perinatal status of Florida manatee carcasses

Differences in perinatal mortality can be indicators of differences in physiology, behavior, toxicology, population dynamics, and ecology of species and individuals. Extensive data collected under the Florida Manatee Carcass Recovery Program provide important information about manatee perinatal mortality. However, early age at death can be difficult to determine for often highly decomposed carcasses. Here, I provide quantitative methods to identify perinatal status for manatee carcasses. First, perinatal and nonperinatal mortality were defined based on physiological indicators. After review of necropsy reports, specific length classes became clear indicators of perinatal status: carcasses <82‐cm long were always perinatal, and carcasses >160‐cm long were always nonperinatal. Using data from carcasses 82–160 cm long of known perinatal status, Bayesian models quantify the relationship among age at death, carcass length, and carcass recovery month. The models predict the perinatal status of carcass 82–160 cm long when physiological indicators are unavailable. Overall, perinatal status could be determined for 98.2% of carcasses collected from 1978 to 2005. Initial examination of the fraction of perinatal mortalities within the entire carcass sample reveals interesting spatial and temporal patterns that warrant further analyses.     

Global Co‐Distribution of Light at Night (LAN) and Cancers of Prostate,Colon, and Lung in Men

The incidence rates of cancers in men differ by countries of the world. We compared the incidence rates of three of the most common cancers (prostate, lung, and colon) in men residing in 164 different countries with the population‐weighted light at night (LAN) exposure and with several developmental and environmental indicators, including per capita income, percent urban population, and electricity consumption. The estimate of per capita LAN exposure was a novel aspect of this study. Both ordinary least squares (OLS) and spatial error (SE) regression models were used in the analysis. We found a significant positive association between population exposure to LAN and incidence rates of prostate cancer, but no such association with lung cancer or colon cancer. The prostate cancer result is consistent with a biological theory and a limited number of previous studies of circadian disruption and risk. The LAN‐prostate cancer connection is postulated to be due to suppression of melatonin and/or disruption of clock gene function. An analysis holding other variables at average values across the 164 countries yielded a risk of prostate cancer in the highest LAN‐exposed countries 110% higher than in the lowest LAN exposed countries. This observed association is a necessary condition for a potentially large effect of LAN on risk of prostate cancer. However, it is not sufficient due to potential confounding by factors that increase the risk of prostate cancer and are also associated with LAN among the studied countries.     

Altered breeding biology of the European blackbird under artificial light at night

Artificial light at night (LAN) has become a stressor of global extent. Previous work has highlighted the high potential of LAN to interfere with annual and diel rhythms of seasonal organisms as well as to affect interactions at the community level. However, our understanding how LAN induced alterations of activity and breeding cycles affect the reproductive outcome and fitness of the birds is still limited. Here, we focus on the effects of night time illumination on the breeding biology of urban European blackbirds Turdus merula. Our results indicate that blackbirds prefer illuminated nest sites and advance their date of clutch initiation by 6 d per 1 lux of night time illumination. Furthermore, daily nest survival rates increased with increasing LAN although this effect was most pronounced for the transition from dark to slightly illuminated sites. We suggest that blackbirds breeding under low artificial night light conditions benefit from the LAN‐avoidance of their major predators (nocturnal) whereas predominant predators of blackbirds nesting in the city centre are diurnal and are, thus, not affected by LAN. Hence, it seems likely that both direct effects of LAN on the timing of reproduction as well as indirect effects on interspecific interactions might contribute to the observed changes in the breeding biology of European blackbirds. This study emphasizes the diverse ecological effects of the night time illumination which are – in its complexity – still poorly understood.     

LIGHT AT NIGHT ALTERS THE PARAMETERS OF THE ECLOSION RHYTHM IN A TROPICAL FRUIT FLY,DROSOPHILA JAMBULINA

We investigated the effects of natural light at night (LAN) in the field and artificial LAN in the laboratory on the circadian rhythm of pupal eclosion in a tropical wild type strain of Drosophila jambulina captured at Galle, Sri Lanka (6.1^oN, 80.2^oE). The influence of natural LAN, varying in intensity from 0.004 lux (starlight intensity) to 0.45 lux (moonlight intensity), on the entrainment pattern of the circadian rhythm of eclosion at 25^o?±?0.5^oC was examined by subjecting the mixed-aged pupae to natural cycles of light and darkness at the breeding site of this strain in the field. The eclosion peak was ～2?h prior to sunrise, and the 24?h rhythmicity was the most robust. Effects of artificial LAN at 25^o?±?0.5^oC were determined in the laboratory by subjecting pupae to LD 12:12 cycles in which the light intensity of the photophase was 500 lux in all LD cycles, while that of the scotophase was either 0 lux (complete darkness, DD), 0.5, 5, or 50 lux. In the 0 lux LAN condition (i.e., the control experiment), the eclosion peak was ～2?h after lights-on, and the 24?h eclosion rhythm was not as strong as in the 0.5 lux LAN condition. The entrainment pattern in 0.5 lux LAN was strikingly similar to that in the field, as the 0.5 lux LAN condition is comparable to the full moonlight intensity in the tropics. LAN at 0.5 lux dramatically altered both parameters of entrainment, as the eclosion peak was advanced by ～4?h and the 24?h eclosion rhythm was better than that of the control experiment. LAN at 5 lux, however, resulted in a weak eclosion rhythm that peaked in the subjective forenoon. Interestingly, the 50 lux LAN condition rendered the eclosion events unambiguously arrhythmic. After-effects of LAN on the period (τ) of the free-running rhythm and the nature of eclosion rhythm were also determined in DD by a single LD 12:12 to DD transfer. After-effects of the LAN intensity were observed on both the τ and nature of the eclosion rhythm in all four experiments. Pupae raised in 0.5 lux LAN exhibited the shortest τ (20.6?±?0.2?h, N?=?11 for this and subsequent values) and the most robust rhythm, while pupae raised in 50 lux LAN had the longest τ (29.5?±?0.2?h) and weakest rhythm in DD. Thus, these results demonstrate the intensity of LAN, varying from 0 to 50 lux, profoundly influences the parameters of entrainment as well as free-running rhythmicity of D. jambulina. Moreover, the observed arrhythmicity in LD 12:12 cycles caused by the 50 lux LAN condition appeared to be the masking effect of relatively bright light at night, as the LD 12:12 to DD transfer restored the rhythmicity, although it was rather weak. (Author correspondence: drdsjoshi08@gmail.com)     

Value and quality of perinatal and infant postmortem examinations: cohort analysis of 400 consecutive deaths.

OBJECTIVES--To evaluate the contribution that perinatal and infant necropsy makes to clinical practice and to see how this might be influenced by the quality of the investigation. DESIGN--Cohort analysis, with data from the all Wales perinatal survey, of perinatal and infant deaths during 1993 of babies born to mothers usually resident in Wales. The clinicopathological classification of death based on clinical details was compared with the classification after necropsy. Similarly, cases in which necropsy yielded new information were identified. The quality of the necropsy was assessed by scoring six aspects of the examination. SUBJECTS--400 consecutive deaths at 20 weeks of gestation to 1 year of age. MAIN OUTCOME MEASURES--Necropsy rate, effect of necropsy on clinicopathological classification, new information disclosed by necropsy, quality of necropsies, and the link between new information and quality of the necropsy. RESULTS--Necropsy was performed in 232 cases (58%). The clinicopathological classification was altered by necropsy in 29 cases (13%). New information was obtained in 60 cases (26%), and in 42 (18%) it disclosed the cause of death. The quality of necropsy was substantially higher when the main cause of death was detected than when nothing new was found. CONCLUSION--Necropsy is underused. Clinicians should be more positive about necropsies and realise how much clinically relevant information can be obtained from a good quality examination.     

Asian mothers' risk factors for perinatal death--the same or different? A 10 year review of Leicestershire perinatal deaths.

A case-control study of all perinatal deaths in Leicestershire was established in 1976. By 1985 some 1342 singleton perinatal deaths had occurred. Perinatal mortality among patients of Asian origin was consistently higher than that among European women. Many of the sociomedical risk factors for perinatal death known at booking were common to both population groups. In this population of Asian women, however, low social class was not associated with perinatal risk and illegitimacy hardly ever occurred. In contrast, previous infertility among the Asian women was associated with risk of perinatal death, while no such association was found with European women. In 19% of perinatal deaths care was either inadequately provided or taken up. The case-control design in these circumstances provides a practicable way to evaluate causal factors and at the same time to provide information of value to educators and health service planners.     

183例早产儿围产期高危因素及并发症分析

目的：探讨早产儿发生的围产期高危因素及并发症。方法：收集我院2006．1—2009．12出生的早产儿183例的临床资料,总结其早产的相关围产期高危因素及并发症。结果：胎膜早破、多胎妊娠、妊娠高血压综合征是早产发生的主要原因;早产儿的主要并发症为肺炎和颅内出血等。结论：加强围生期保健,早期干预各种围产期高危因素,积极防治早产儿各种并发症,是提高早产儿存活率降低致残率的关键。     

The Influence of Lentinan on the Capacity of Repair of DNA Damage and Apoptosis Induced by Paclitaxel in Mouse Bone Marrow Cells

The ability of the flavonoid lentinan (LAN) to enhance the repair of paclitaxel (PAC)‐induced DNA damage and apoptosis in mouse bone marrow cells was investigated. Moreover, the possible mechanism underlying this modulation was determined. LAN was neither genotoxic nor apoptogenic at doses equivalent to 1 or 2 mg/kg/day. Pretreatment of mice with LAN significantly enhances the repair of PAC‐induced DNA damage and bone marrow suppression in a dose dependent manner. Moreover, LAN affords significant protection against PAC‐induced apoptosis. A significant increase of reactive oxygen species and a decrease in reduced glutathione levels were observed after PAC treatment and prior administration of LAN before PAC challenge ameliorated these oxidative stress markers. Conclusively, our study provides, for the first time, that LAN enhances the repair of PAC‐induced DNA damage and apoptosis that resides, at least in part, on its ability to modulate the cellular antioxidant levels and consequently protect bone marrow cells from PAC genotoxicity. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:370‐377, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21499     

夜间光照对褪黑激素抑制的量化计算

作为人体的重要激素之一,褪黑激素具备重要的生理功能．不适当的夜间光照会造成人体生物钟节律的异常,进而导致褪黑激素内分泌的抑制．夜间光照引起的褪黑激素抑制与光的波长和色温关系密切．此前尚仍缺乏一个夜间光照对褪黑激素抑制效果的量化计算方案．提出了一种夜间光照对褪黑激素抑制的量化算法,拟合了人体血液褪黑激素抑制率的相对光谱灵敏度归一化曲线,建立了夜间光照与褪黑激素抑制量化计算的算法模型．研究结果为室内安全光照环境的设计提供了理论依据和计算方法,并可在光污染的控制、夜间安全环境照明标准的制定等方面得到应用．