Light exposure from microscope versus intracameral illumination during cataract surgery

Purpose: To evaluate light exposure from microscope versus intracameral illuminations to patient's and surgeon's retina during cataract surgery. Methods: Thirty consecutive patients who had cataract surgery using microscope and intracameral illuminations. At the point of the ocular of an operating microscope, optical illuminance and irradiance from the microscope illumination (60, 40, 20% intensity) and the intracameral illumination (60% intensity) were measured using a light meter and a spectrometer at a pause after lens capsule polishing in cataract surgery. Results: Average illuminance (lux) was 1.46, 0.66, 0.27, and 0.1 from 60%, 40%, 20% intensity microscope illuminations and 60% intracameral illumination. Average total spectral irradiance (?W/cm2) was 1.25, 0.65, 0.26, and 0.03 from 60%, 40%, 20% intensity microscope illuminations and 60% intracameral illumination. Conclusion: Microscope ocular illuminance and irradiance during cataract surgery were higher in the microscope illumination than in the intracameral illumination. It suggests that light exposure reaching patient's and surgeon's retina during cataract surgery is lower in the intracameral illumination than in the microscope illumination.

Light-induced injury in mouse embryos revealed by single-cell RNA sequencing

BACKGROUND: Light exposure is a common stress factor in in vitro manipulation of embryos in the reproductive center. Many studies have shown the deleterious effects of high-intensity light exposure in different animal embryos. However, no transcriptomic studies have explored the light-induced injury and response in preimplantation embryos. RESULTS: Here, we adopt different time-courses and illumination intensities to treat mouse embryos at the 2-cell stage and evaluate their effects on blastulation. Meanwhile, single-cell transcriptomes from the 2-cell to blastocyst stage were analyzed after high-intensity light exposure. These data show that cells at each embryonic stage can be categorized into different light conditions. Further analyses of differentially expressed genes and GO terms revealed the light-induced injury as well as the potential repair response after high-intensity lighting. Maternal-to-zygote transition is also affected by the failure to remove maternal RNAs and deactivate zygotic genome expression. CONCLUSION: Our work revealed an integrated response to high-intensity lighting, involving morphological changes, long-lasting injury effects, and intracellular damage repair mechanisms.

Effects of Light on Daytime Sleep in 12 Hours Night Shift Workers: A Field Study

OBJECTIVES: Night shift workers suffer from sleep and daytime disturbances due to circadian misalignment. To investigate the role of environmental light in daytime sleep following 12 h-night shift work. METHODS: We enrolled 12 h-shift female nurses working at one university-affiliated hospital (n=10, mean age 26.6 years, shift work duration 3.8 years). This is a cross-over study to compare sleep between under light exposure (30 lux) and in the dark (<5 lux) following 12 h-night duty. Two sessions of experiments were underwent and the interval between sessions was about a month. Psychomotor vigilance test (PVT) had performed on awakening from sleep at each session and sleep-wake pattern had been monitored by actigraphy throughout the study period. Daytime sleep was also compared with night sleep of age-and gender matched daytime workers (n=10). RESULTS: Sleep parameters and PVT scores were not different between two light conditions. Activities during sleep seemed to be more abundant under 30 lux condition than in the dark, which was not significant. Compared to night sleep, daytime sleep of shift workers was different in terms of rapid eye movement (REM) sleep. Three shift workers showed sleep onset REM sleep and first REM sleep period was the longest during daytime sleep. CONCLUSIONS: Unexpectedly, daytime sleep of 12 h night shift workers was well-maintained regardless of light exposure. Early occurrence of REM sleep and shorter sleep latency during daytime sleep suggest that shift workers meet with misalignment of circadian rhythm as well as increased homeostatic sleep pressure drive.

Association between vitamin D deficiency and age-related macular degeneration / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To explore the correlation between vitamin D(Vit-D)deficiency and age-related macular degeneration(ARMD).<p>METHODS: A total of 423 cases of middle-aged and aged outpatients(age>45 years)who participated in the physical examination in ophthalmology clinic of Yuncheng First Hospital during February 2018 to February 2019 were included in the cross-sectional study. The clinical information(including sex, age, family history of ARMD, <i>etc.</i>)and biochemical indices(including 25-hydroxyvitamin D \〖25(OH)D\〗, <i>etc.</i>)were collected. The correlations between serum 25(OH)D level and clinical information, as well as biochemical indices, were analyzed. The outpatients were divided into ARMD group(231 cases)and non-ARMD group(192 cases)according to the ARMD situation in the study. The correlation between Vit-D deficiency and ARMD was analyzed.<p>RESULTS: Serum 25(OH)D level was positively correlated with the male, duration of outdoor light exposure(<i>P</i><0.05), and negatively correlated with age, smoking and drinking(<i>P</i><0.05). Binary Logistic regression analysis showed that Vit-D deficiency was a risk factor associated with ARMD(<i>OR</i>=1.980, 95% <i>CI</i>: 1.829-2.201, <i>P</i><0.01). Other associated factors included age, sex, hypertension, diabetes, low-density lipoprotein cholesterol(LDL-C), and duration of outdoor light exposure >5h/d, which were also risk factors associated with ARMD.<p>CONCLUSION: Nutritional imbalance due to Vit-D deficiency might be associated with the occurrence of ARMD. Appropriate sun exposure or vit-D supplements could contribute to preventing the development of ARMD.

Influence of Light Exposure on Inflammatory Bowel Disease / 胃肠病学

Light exposure is a very important environmental factor. Increased light exposure may lead to disturbed circadian rhythm or sleep, resulting in dysregulation of the circadian clock gene, secretion of melatonin, intestinal immunity, and bacterial flora, which in turn affect the condition of IBD patients. This article reviewed the effect of light exposure on IBD.

Effects of constant light exposure on obesity in high fat diet rats / 中华内分泌代谢杂志

Objective To observe the effects of constant light exposure on the obesity in high fat diet rats. Methods Thirty-two male SD rats were randomly divided into four groups:rats on a normal chow exposed to standard light-dark cycle ( group A) , rats on a normal chow exposed to constant light ( group B) , rats on a high fat diet exposed to standard light-dark cycle ( group C) , and rats on a high fat diet exposed to constant light ( group D) . Body weights and food intakes were recorded weekly throughout the 12-week study. Body weight, fat mass, visceral adipose tissue weight, intraperitoneal glucose tolerance test ( IPGTT) results, insulin resistance parameters, serum lipids and levels of interleukin 6 (IL-6), tumor necrosis factor-α(TNF-α) were compared among groups. Epididymal adipose tissues mRNA expression of circadian clock genes, i. e. clock, bmal1, rorα, rev-erbα, cry1, per1, and per2 were analyzed by realtime PCR. Results From the 9th week, body weights of rats in group D were significantly higher than those in group C (all P<0. 05). At the 12th week, area under curve of IPGTT (AUC-IPGTT) in groups B, C, and D were significantly higher than that in group A. AUC-IPGTT in group D was significantly higher than that in group C (all P<0.05). Compared with group C,asignificant increase in fat mass,visceral adipose tissue weight,homeostasis model assessment for insulin resistance, serum cholesterol, TNF-α levels were observed in group D ( all P<0. 05). And a significant decrease in quantitative insulin sensitivity check index ( QUICKI) and high density lipoprotein-cholesterol were observed in group D in comparison with group C (both P<0. 05). Circadian clock genes (clock, rorα, rev-erbα, cry1, per1) mRNA expressions in group B and D were significantly different from those in group A (all P<0. 05) . Expression of cry1 in group D was significantly higher than that in group C. In group C, rev-erbαmRNA expression was significantly down-regulated in comparison with group A (P<0. 05). Conclusion Constant light exposure exaggerates obesity, glycolipid metabolism abnormality, inflammation, and insulin resistance in high fat diet rats.

Sensibilidade de isolados de fungos entomopatogênicos às radiações solar, ultravioleta e à temperatura / Sensibility of isolates of entomopathogenic fungi to solar radiation, ultraviolet rays and temperature

Este trabalho teve por objetivo avaliar a sensibilidade de isolados dos fungos Metarhizium anisopliae (Metsch.) Sorok. e Beauveria bassiana (Bals). Vuill. ao efeito das radiações solar e ultravioleta e da temperatura. Conídios dos isolados foram expostos, por vários períodos, aos raios de um simulador solar em diversas irradiâncias e a uma lâmpada de raios ultravioleta germicida. Os conídios do isolado de M. anisopliae foram também expostos às temperaturas de 19,5; 24,2 e 31,0ºC, e os do isolado de B. bassiana a 19,4; 20,8 e 28,3ºC, e 18,7; 23,8 e 30,9ºC. Avaliou-se a germinação de conídios pelo teste de viabilidade. Os isolados dos fungos se mostraram bastantes sensíveis aos raios do simulador solar e aos raios ultravioleta. A germinação de ambos sofreu significativa redução a partir de 30 minutos de exposição à radiação do simulador solar. O efeito mais severo foi evidenciado pelo isolado de B. bassiana, com grande redução da germinação dos conídios em todas as irradiâncias testadas. A sensibilidade à radiação ultravioleta também foi grande, pois ocorreu acentuada redução da germinação dos conídios do isolado de M. anisopliae (38,2%) e de B. bassiana (65%) já aos 30 segundos de exposição. A temperatura afetou a viabilidade de ambos os fungos. Temperaturas entre 23,8 e 31ºC favoreceram a germinação dos conídios, enquanto temperaturas próximas de 20ºC dificultaram a germinação.(AU)

This study aimed to access the sensibility of isolates of the fungus Metarhizium anisopliae (Metsch.) Sorok. and Beauveria bassiana (Bals.) Vuill. to the effect of solar and ultraviolet radiation and temperature. Conidia were exposed for various periods to the rays from a solar simulator at various irradiances, and to light germicidal ultraviolet rays. Conidia of the isolate of M. anisopliae were also exposed to temperatures of 19.5, 24.2 and 31.0ºC and the isolate of B. bassiana to 19.4, 20.8 and 28.3ºC, and also to 18.7, 23.8 and 30.9ºC. The germination of conidia was evaluated by the viability test. The fungal isolates showed to be very sensitive to the solar simulator and ultraviolet rays. Germination of both was significantly decreased starting from 30 minutes of exposure to the rays of the solar simulator. The most severe effect was evidenced by the isolate of B. bassiana with great reduction in conidia germination in all the tested irradiances. Sensitivity to ultraviolet radiation was also great, showing a marked reduction in the germination of M. anisopliae (38.2%) and B. bassiana (65%) conidia after 30 seconds of exposure. The temperature affected the viability of both fungi. Temperatures ranging of 23.8 to 31ºC favor the germination of conidia while temperatures around 20ºC constrained germination.(AU)

Light Exposure and Sleep-Wake Pattern in Rapidly Rotating Shift Nurses

OBJECTIVES: Shift workers are at risk for various sleep and health-related problems. To investigate light exposure and sleep-wake pattern according to shift schedules in shift workers. METHODS: We enrolled 12 full-time, rapidly rotating three-shift female nurses (age 26.4±4.01 years). They completed sleep logs and actigraphy monitoring of sleep-wake parameters, light exposure, and activity levels for over 14 days (mean numbers of night shifts 2.5). RESULTS: Before beginning shift work, participants were healthy and had no history of hypnotics. One third of participants (33.3%) had clinically significant insomnia-related symptoms (insomnia severity index ≥15, mean 14.0). Reported health problems were irregular menstruation cycles (75%), nightmares (25%), and irritable bowel syndrome (16.7%). Mean sleep time was less than 6 h regardless of the shift periods and wakefulness after sleep onset was prolonged more than 30 min. Light exposure in night-shift periods was the lowest during working hours and the highest during non-working hours. Activity levels were not different during working hours throughout the schedules. CONCLUSIONS: Fast-rotating shift nurses sleep less and unsatisfactorily. Health-related problems were frequent in shift nurses. Rapidly rotating shift schedules and related inappropriate light exposure may be detrimental to sleep and health in shift workers.

Two methods for air disinfection in neurosurgical intensive care unit / 现代临床护理

Objective To compare the effects of Chinese herbal fumigation and ultraviolet light exposure on air disinfection in neurosurgical intensive care unit.Methods The floors and the tables in the rooms of ICU were all disinfected using 0.02%84 disinfectant.The air disinfection was performed in the rooms using Chinese herbal(elsholtziae,ramulus cinnamomi,forsythia suspense,flos caryophylli)fumigation as the experiment group and those using ultraviolet light exposure as the control group,both for 30 times.The two disinfection methods were compared before air disinfection,at hours 0,1,2,4,8 and 12 in terms of bacteria tests.Results The air quality on natural bacteria in both groups met the standard of Class Ⅱ Environmental Health Criteria at hour 0,l after air disinfection,without significant difference between the two groups at each time point(P>0.05).In the control group,the bacteria began to grow in number one hour after ultraviolet light exposure and overgrew two hours after air disinfection.In the experiment group,the bacteria grew less,never exceeding the standard level at all time points.The disinfection effect of the experimental group was all significantly better than that of the control group at the time points of 2 h,4 h,8 h,12 h(P<0.05 or P<0.01). Conclusions Chinese herbal fumigation is superior to the UV light irradiation disinfection.It is safe and harmless even in case of medical staff working in the unit.

The effect of light exposure at night on retinal neovascularization in a mouse model of oxygen-induced retinopathy / 中华实验眼科杂志

Background Oxygen-induced retinal neovascularization is the main pathological basis for many retinal vascular diseases.Research showed that light exposure at night can suppress retinal neovascularization in oxygen-induced retinopathy(OIR),but there were few reports discussing its effect on ROP.Objective This study aimed to observe the effect of light exposure at night on retinal neovascularization in an OIR mouse model.Methods Sixty-four newborn C57 BL/6J mice were randomly divided into four groups,with 16 mice for each group.OIR models were established by rearing the newborn C57BL/6J mice with their mothers in a(75±2)％ oxygen environment from postnatal day 7(P7)to Pl2,and then transferred to room air.In the OIR model group,the environmental illumination level was the same as the normal control group,and the model mice were exposed to 100 lx light at night in the OIR+ light exposure group.In the simple light exposure group,normal mice were reared in room air and were exposed to light at night from P12 to P17.All the mice were sacrificed on P17,and retinal flat mounts were prepared to assess the oxygen-induced changes of retinal vessels using the adenosine diphosphatase(ADPase)histochemical technique.The amount of proliferative neovascularization was quantified by counting the number of endotheliocyte nuclei in new vessels extending from the retinal inner limiting membrane into the vitreous in ocular cross-sections.The expression of the vascular endothelial growth factor(VEGF)protein was detected by immunohistochemistry.Real-time PCR analysis was performed to examine the expression of VEGF mRNA.The rearing and usage of the animals complied with the Statement of ARVO.Results Less free-vascular areas and new blood vessels were seen in the OIR+light exposure group compared with the OIR model group.On day 17 of the mouse life,the number of the endotheliocyte nuclei in new vessels extending from retinal inner limiting membrane were 0.97±0.83,1.00±0.72,38.57±5.01 and 16.92±3.39 in the normal group,simple light exposure group,OIR model group and OIR+light exposure group,respectively,showing significant differences among them(F =78.767,P =0.000).The number of nuclei in the OIR+light exposure group were less than that of the OIR model group(t=20.446,P＜0.01).Immunochemistry showed that the expression of VEGF in retina was weaker in the OIR+light exposure group than the OIR model group.The relative expression values of VEGF mRNA were 1.00±0.00,0.94±0.07,2.08±0.50 and 1.43±0.21 in the normal group,simple light exposure group,OIR model group and OIR+light exposure group,respectively,showing a significant difference (F=11.268,P =0.003),where the VEGF mRNA level in the OIR+light exposure group was lower than that of the OIR model group(t =20.163,P＜0.05).Conclusions Light exposure at night can weaken retinal neovascularization in OIR mice

Effects of different wave-length lights on proliferation and secretion of growth factors in human retinal pigment epithelium cells / 中华实验眼科杂志

BackgroundThe study of myopia development is always the hotspot worldwide. Recently,scientist found that some growth factor secreted by retinal nerve epithelium cells and retinal pigment epithelium(RPE)cells are associated with the development of myopia. Whenever, the absorption of RPE cells to different wave-length lights is different. ObjectiveThis study was to investigate the effects of different wave-lengths lights on the proliferation of human RPE cells, and explore the influence of different wave-lengths lights on RPE cells secreting hepatocyte growth factor(HGF) ,basic fibroblast growth factor(bFGF) and transforming growth factor-β(TGF-β).Methods The fourth to fifth passages of human embryonic RPE cells were exposed to blue light( λ =480 nm),red light( λ =775 nm) and white light. The cells of control group were harvested in normal condition. The proliferation and growth of RPE cells were assayed by MTT,and the ultrastructure of cells was examined under the transmission electron microscopy at 48 hours after light exposure of RPE cells. Enzyme linked immunosorbent assay(ELISA) was adopted to determine the concentrations of HGF,bFGF and TGF-β in the culture medium in 12,24,48,72 hours. The expression of HGF mRNA in RPE cells was detected by RT-PCR. This study was approved by Ethic committee of Fudan University. ResultsThe A490 values of the cells exposed to blue light,red light,white light and white light were 0. 0218±0. 0014 ;0. 0353±0. 0025 ;0. 0371 ±0. 0024 and 0. 0445 +0. 0046 respectively with the significant difference among 4 groups ( F =12. 579, P＜0.05 ), and A490 value in blue light group, red light group were significantly lower than that of the control group ( t =2.043 ; t =2.024, P＜0.05 ). ELISA showed that the concentrations of HGF and TGF-β in culture medium were evidently elevated as the prolongation of light exposure in various light exposure groups in 72 hours(HGF) and 48 hours(TGF-β) compared with 12 hours with a predominating rise in the control group. The statistically significant differences were found in the concentrations of HGF and TGF-β between control group and blue light group or red light group in the( all P＜0. 05 ). The bFGF level was decreased with the time increase of various light exposure with the significant differences in 72 hours compared with 12 hours( P＜0.05 ). RT-PCR revealed the considerable difference about expression of HGF mRNA in RPE cells among these four groups( P＜0. 05 ), and the lest expression in HGF mRNA was in the blue light group compared with control group( t =3. 972,P＜0.05 ). Thinning of the chromatin, decreasing of organelle and loss of cellular membrane were seen in the blue light group, but no obvious change of ultrastructure of human embryo RPE cells was found in the ret and white light groups. ConclusionsThe irradiation of different wave-length light can effect the growth and proliferation and secretion of HGF,bFGF and TGFβ in human RPE cells in vitro,implying myopia formation is associated to exposure of different wave-length light.

THE RESPONSES OF VISUAL FUNCTION TO LUTEIN SUPPLEMENTS IN PEOPLE WITH LONG-TERM DISPLAY LIGHT EXPOSURE / 营养学报

Objective To examine the effect of lutein supplementation on visual function in people with long-term display light exposure. Method Thirty-seven persons (age 22-30) with long-term display light exposure were divided into low-dose group, high-dose group, and placebo group involving supplementation with 6 mg lutein/d, 12 mg lutein/d, and placebo for 12 w. The levels of serum lutein and visual function indices such as break-up time (BUT), critical flicker fusion frequency (CFF), visuognosis persistence, and reaction time were measured at week 0 and 12. Results After lutein supplementation serum concentrations of high-dose group and low-dose group increased from (0.328?0.120) ?mol/L to (0.733?0.354) ?mol/L, and from (0.356?0.117) ?mol/L to (0.607?0.176) ?mol/L respectively. There was significant increase of break up time in left eyes of high-dose group. Visuognosis persistence was significantly improved, and significant decrease of simple reaction time was observed in high-dose group. No statistical change was observed in critical flicker fusion frequency, discriminative reaction time and choice reaction time during the study. Conclusion Visual function indices such as break-up time, visuognosis persistence and simple reaction time in people with long-term display light exposure who received lutein supplements were significantly improved.