感染性休克患者降钙素原和C-反应蛋白动态变化研究

目的观察降钙素原(PCT)、C-反应蛋白(CRP)等指标在感染性休克患者中的动态变化和急性生理和慢性健康(APACHEⅡ)评分在预后评估中的作用。方法回顾性分析45例感染性休克患者入院第1、3、5天以及出院或死亡前最后一次的血清PCT、CRP及入院时APACHEⅡ评分,根据预后将患者分为死亡组及存活组,并对其进行分析。结果 45例感染性休克患者生存20例,死亡25例,病死率为55.6%。死亡组患者入院时APACHEⅡ评分明显高于存活组[(28.84±8.03)分vs(21.82±7.10)分]。两组在入组第1、3天的PCT和CRP水平比较差异均无统计学意义。死亡组PCT和CRP水平在第5天及观察终点均明显高于存活组。各组内PCT和CRP与观察第1天相比,存活组随观察时间延长而明显下降,差异有统计学意义,而死亡组则无明显变化。结论患者血清中PCT、CRP呈持续高水平提示预后不佳,指标的高低对临床指导治疗和评估预后有参考意义。     

血清肾上腺髓质素原、降钙素原、D-二聚体水平对急诊慢性阻塞性肺疾病急性加重并Ⅱ型呼吸衰竭患者预后的预测价值

目的分析血清肾上腺髓质素原(pro-ADM)、降钙素原(PCT)、D-二聚体水平对急诊慢性阻塞性肺疾病急性加重(AECOPD)并Ⅱ型呼吸衰竭患者预后的预测价值。方法选取2017年1月—2018年7月于北京市垂杨柳医院急诊科就诊留观及急诊重症监护病房(EICU)住院的AECOPD并Ⅱ型呼吸衰竭患者102例,根据28 d存活情况分为存活组71例和死亡组31例。比较两组患者就诊24 h内CURB-65评分、急性生理学与慢性健康状况评分系统Ⅱ(APACHEⅡ)评分及确诊后第1、4天血清pro-ADM、PCT、D-二聚体、C反应蛋白(CRP)水平,绘制ROC曲线以分析确诊后第1天血清pro-ADM、PCT、D-二聚体、CRP水平对急诊AECOPD并Ⅱ型呼吸衰竭患者预后的预测价值,并根据机械通气情况进行亚组分析。结果 (1)死亡组患者就诊24 h内CURB-65评分、APACHEⅡ评分高于存活组(P0.05)。(2)死亡组患者确诊后第1、4天血清pro-ADM、PCT、D-二聚体水平及确诊后第4天血清CRP水平高于存活组,而确诊后第1天血清CRP水平低于存活组(P0.05)。(3)存活组患者中行机械通气者11例,未行机械通气者60例。存活组患者中是否行机械通气者就诊24 h内CURB-65评分、APACHEⅡ评分比较,差异无统计学意义(P0.05);存活组患者中行机械通气者确诊后第1、4天血清pro-ADM水平高于未行机械通气者(P0.05),而存活组患者中是否行机械通气者确诊后第1、4天血清PCT、D-二聚体、CRP水平比较,差异无统计学意义(P0.05)。(4)ROC曲线显示,确诊后第1天血清pro-ADM、PCT、D-二聚体、CRP水平预测急诊AECOPD并Ⅱ型呼吸衰竭患者预后的曲线下面积(AUC)分别为0.983[95%CI(0.963,1.000)]、0.718[95%CI(0.670,0.819)]、0.918[95%CI(0.863,0.972)]、0.325[95%CI(0.198,0.451)];确诊后第1天血清pro-ADM、PCT、D-二聚体、CRP水平预测28 d存活的急诊AECOPD并Ⅱ型呼吸衰竭患者机械通气的AUC分别为0.720[95%CI(0.553,0.888)]、0.664[95%CI(0.512,0.817)]、0.651[95%CI(0.493,0.808)]、0.498[95%CI(0.293,0.704)]。结论 28 d死亡的急诊AECOPD并Ⅱ型呼吸衰竭患者血清pro-ADM、PCT、D-二聚体水平较高,三者对急诊AECOPD并Ⅱ型呼吸衰竭患者预后的预测价值较高并对28 d存活者机械通气有一定预测价值,因此临床对于血清pro-ADM、PCT、D-二聚体水平尤其是血清pro-ADM水平升高的急诊AECOPD并Ⅱ型呼吸衰竭患者应引起重视。     

降钙素原在重症监护患者细菌感染的预后价值

目的探讨血清降钙素原(PCT)对重症患者细菌感染性疾病预后评估和病情严重程度判断的价值。方法选取116例细菌感染性疾病患者,采用免疫色谱法检测入院后24 h内的血清PCT水平,记录患者24 h急性生理学与慢性健康状况Ⅱ(APACHEⅡ)评分。根据28 d临床结局,分为死亡组(36例)和存活组(80例),比较两组间PCT、APACHEⅡ评分的差异,分析血清PCT水平与APACHEⅡ评分的相关性,用受试者工作特征曲线(ROC)下面积(AUC)评估PCT单独应用及联合PCT和APACHEⅡ评分预测28 d生存情况的效能。对PCT和APACHEⅡ评分预测28 d生存情况的效能进行比较。结果死亡组PCT水平明显高于存活组(Z=5.598,P0.001),死亡组APACHEⅡ评分亦显著高于存活组(t=6.148,P0.01)。PCT与APACHEⅡ评分存在显著正相关(r=0.388,P0.001),PCT和APACHEⅡ评分预测重症患者细菌感染性疾病28 d生存情况的AUC分别为0.804和0.792,PCT的AUC值高于APACHEⅡ评分,但差异无统计学意义(U=0.2073,P=0.802)。联合PCT和APACHEⅡ评分预测28 d生存情况的ACU较单一指标高,为0.817,敏感度90.7%,特异度75.2%,均优于单一指标的预测效能。结论血清PCT能反映重症患者细菌感染性疾病病情严重程度及预后,是预测28 d生存情况的有效指标,联合PCT检测和APACHEⅡ评分可提高预测效能。     

CRP、PCT与APACHEⅡ评分判断ICU老年重症感染患者预后的价值

目的探讨C反应蛋白(CRP)、降钙素原(PCT)及急性生理和慢性健康状况评分(APACHE)Ⅱ对重症监护病房(ICU)老年重症感染患者预后的判断价值。方法回顾性分析老年脓毒症患者175例临床资料,按照患者病情严重程度将其分为脓毒症组70例、严重脓毒症组59例、脓毒症休克组46例,根据患者临床预后分为存活组133例、死亡组42例,比较分析各组CRP、PCT及APACHEⅡ评分,并采用受试者工作特征(ROC)曲线分析各指标对患者临床预后判断价值。结果不同病情严重程度患者CRP、PCT及APACHEⅡ评分差异有统计学意义(P0.05),随着患者病情严重程度增加,CRP、PCT及APACHEⅡ评分明显升高(P0.05)。死亡组CRP、PCT及APACHEⅡ评分均显著高于存活组(P0.05)。PCT、CRP及APACHEⅡ评分两两互呈显著正相关(P0.05)。采用ROC曲线分析CRP、PCT、APACHEⅡ评分及三者联合对患者预后的预测价值,CRP曲线下面积为0.817,PCT曲线下面积为0.798,APACHEⅡ评分曲线下面积为0.809,三项指标联合曲线下面积为0.893。结论联合运用CRP、PCT及APACHEⅡ评分对ICU老年重症感染患者临床预后具有较高的评估价值。     

C-反应蛋白和前白蛋白评估社区获得性肺炎患者预后的应用

目的探讨社区获得性肺炎(CAP)患者前白蛋白(PA)及C-反应蛋白(CRP)的变化和其与病情严重程度及预后的关系。方法测定我院内科92例CAP患者入院第1天与第7天的CRP、PA、SIRS评分和APACHEⅡ评分,按预后把患者分成死亡组和存活组。结果死亡组入院第1天CRP、PA与存活组比较无差异,SIRS和APACHEⅡ评分均大于存活组(P0.05);死亡组第7天PA较前降低(P0.05),CRP、SIRS评分和APACHEⅡ较前相比无差异(P0.05);存活组第7天CRP、SIRS和APACHEⅡ评分较第1天降低,PA较前升高(P0.05),与死亡组相比有显著性差异。结论CRP持续高水平与PA持续低水平是预后不良的表现,动态观察CRP和PA水平对预测CAP患者预后有重要意义。     

降钙素原和APACH Ⅱ评分对老年脓毒症患者病情判断及预后评估的研究

目的探讨血清降钙素原(PCT)和急性生理学与慢性健康状况Ⅱ(APACHEⅡ)评分对老年脓毒症患者病情判断评估及预后预测的价值。方法采用前瞻性方法进行研究,选取2012年1月至2014年1月期间收住我院干部病房的老年脓毒症113例患者作为研究对象。采用免疫色谱法检测血清PCT水平,记录患者24 h APACHEⅡ评分,同时对PCT及APACHEⅡ评分进行双变量相关分析。结果依据APACHEⅡ评分共分为3组;评分20分为高危组,共34例;评分10~20分为中危组,共52例;评分10分为低危组,共27例;低危、中危、高危组APACHEⅡ评分分别为(16.50±3.89)分、(20.93±3.27)分和(26.68±6.56)分。将研究对象按照28 d预后分为存活组72例,死亡组41例。低危组、中危组和高危组血清PCT分别为(0.16±0.15)ng/ml、(0.63±0.62)ng/ml和(5.62±5.21)ng/ml,组间差异有统计学意义(P0.05或P0.01)。死亡组血清PCT[(5.21±4.88)ng/ml]和APACHEⅡ评分[(30.60±10.20)分]均高于存活组,差异有统计学意义(P0.05)。相关分析显示PCT与APACHEⅡ评分及CRP明显相关,相关系数分别为0.581和0.611(P0.05)。结论血清PCT是反映老年脓毒症患者病情严重程度及预后的有效指标,血清PCT和APACHEⅡ评分可用于预测老年脓毒症患者病情严重程度及预后预测。     

降钙素原及C反应蛋白水平在重症肺炎患者预后中的作用

目的：探讨降钙素原（Procalcitonin，PCT）及C反应蛋白水平（C-reactionprotein，CRP）在重症肺炎患者预后判断及转归中的作用 方法：2012年2月-2014年12月，回顾性分析我科收治重症肺炎患者65例，按照预后情况分为死亡组和存活组，对比分析两组间的临床一般特征、入院治疗前、48h、72h、出院前或死亡前PCT、CRP水平及APACHEⅡ评分 结果：两组患者PCT、CRP水平均较正常值明显升高，其中死亡组PCT 、CRP水平较存活组明显提高（P<0.01）。通过连续监测PCT、CRP水平发现抗生素使用有效时PCT水平明显降低，而CRP水平下降速度较PCT明显降低。血清 PCT 水平与APACHEⅡ评分的相关系数为 0.689，其相关性均高于CRP。PCT、CRP水平的升高与患者死亡具有相关性，OR值( 95% CI)分别为 2.9 (1.2- 7.8 )、7.4( 3.5 ~ 18.7) (P=0.003,0.001 )。结论：PCT、CRP水平在重症肺炎患者预后判断及转归中具有较好的作用，其中PCT水平监测效果优于CRP水平。     

降钙素原及C反应蛋白水平对重症肺炎预后的评估

目的:探讨降钙素原(PCT)及C反应蛋白(CRP)水平在重症肺炎患者预后判断及转归中的作用。方法:回顾性分析65例重症肺炎患者的临床病历资料,分为死亡组(29例)和存活组(36例),对比2组的临床特征、治疗前、入院后48、72 h、出院前或死亡前血PCT、CRP水平及APACHEⅡ评分。结果:2组患者血PCT、CRP水平均较正常值明显升高,其中死亡组血PCT、CRP水平较存活组明显升高(P0.01)。抗生素使用有效时血PCT水平明显降低,而血CRP水平下降速度较PCT慢。血清PCT水平与APACHEⅡ评分的相关系数高于CRP(r分别为0.689、0.432)。血PCT和CRP水平升高与患者死亡相关,OR值(95%CI)分别为2.9(1.2~7.8)、7.4(3.5~18.7)(P0.05)。结论:血PCT和CRP水平对判断重症肺炎患者预后及转归有较好的作用,其中血PCT优于CRP水平。     

血清降钙素原、C-反应蛋白及乳酸对老年脓毒症患者的预后评估

目的探讨老年脓毒症患者血清降钙素原(PCT)、C-反应蛋白(CRP)及乳酸水平与急性生理学与慢性健康状况评分系统Ⅱ(APACHEⅡ)评分及序贯性器官功能衰竭评估(SOFA)评分的相关性,分析其对脓毒症患者的预后评估价值。方法选取我院收治的老年脓毒症患者186例,根据其28 d生存情况的随访结果分为存活组(110例)和死亡组(76例)。检测两组患者血清PCT、CRP及乳酸水平变化,并记录入院时APACHEⅡ、SOFA评分情况。采用t检验、重复测量的方差分析、χ~2检验或Fisher精确检验对两组数据进行分析。应用受试者工作特征(ROC)曲线分析血清PCT、CRP及乳酸对老年脓毒症患者预后的评估价值。采用Pearson相关分析法分析死亡组血清PCT、CRP及乳酸水平与APACHEⅡ、SOFA评分的相关性。结果死亡组第1、3、7天血清PCT、CRP及乳酸水平均明显高于存活组(P0.05),且死亡组第7天血清PCT、CRP及乳酸水平明显高于第1、3天(P0.05)。存活组第7天血清PCT、CRP及乳酸水平均明显低于第1、3天(P0.05)。Logistic回归分析发现,PCT、CRP、乳酸及SOFA评分是老年脓毒症患者预后不良的独立影响因素。ROC曲线显示,PCT_(d3)、CRP_(d3)及乳酸_(d3)评估老年脓毒症患者预后的最佳截值分别为9.83μg/L、86.42 mg/L和3.72 mmol/L,其敏感度和特异度较好,分别为81.7%和85.3%,77.5%和79.8%,86.3%和76.2%。相关分析显示,死亡组血清PCT_(d3)与APACHEⅡ评分、SOFA评分的相关性较好(r=0.703,P0.001;r=0.802,P0.001)。结论血清PCT、CRP及乳酸水平与老年脓毒症患者的病情严重程度及预后密切相关,第3天血清PCT水平预测患者预后的价值最大。     

脓毒症患者血清硫氧还蛋白水平检测的临床意义

目的：探讨脓毒症患者血清硫氧还蛋白（Trx)水平及其临床意义。方法：选择脓毒症患者80例,根据病情严重程度分为脓毒症组48例,脓毒性休克组32例。另选择同期健康体检者40例作为对照组。比较3组白细胞计数(WBC)、C反应蛋白(CRP)、降钙素原(PCT)、Trx水平;比较脓毒症组与脓毒性休克组急性生理与慢性健康状况评估（APACHEⅡ）评分、序贯器官衰竭评估（SOFA）评分以及住院病死率;比较死亡组与存活组血WBC、CRP、PCT、Trx水平;分析Trx与脓毒症患者血WBC、CRP、PCT水平、APACHEⅡ评分、SOFA评分以及住院病死率的相关性。结果：脓毒症组与脓毒性休克组血WBC、CRP、PCT水平显著高于对照组,Trx水平显著低于对照组（均P＜0.05）;脓毒性休克组血WBC、CRP、PCT水平、APACHEⅡ评分、SOFA评分以及病死率显著高于脓毒症组,Trx水平显著低于脓毒症组（均P＜0.05）。与死亡组比较,存活组血WBC、CRP、PCT水平显著更低,Trx水平显著更高（均P＜0.05）。Trx与WBC、CRP、PCT、APACHEⅡ评分、SOFA评分、病死率呈显著负相关（均P＜0.05）。结论:脓毒症患者血清Trx水平显著下降,且脓毒性休克患者下降更显著,Trx水平与患者病情严重程度呈显著负相关。     

Three layer functional model and energy exchange concept of aging process

Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.     

Unusual responses of nocturnal pineal melatonin synthesis and secretion to swimming: Attempts to define mechanisms

Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm²) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.     

Melatonin and photoperiodic time measurement: Seasonal breeding in the sheep

Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.     

Serological survey of HIV and syphilis in pregnant women in Madagascar

Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.     

Variabilité des concentrations plasmatiques de l’angiotensinogène et risque d’hypertension artérielle chez le rat transgénique

Aim

Genetic polymorphisms of the human angiotensinogen gene are frequent and may induce up to 30% increase of plasma angiotensinogen concentrations with a blood pressure increase of up to 5 mmHg. Their role for the pathogenesis of human arterial hypertension remains unclear. High plasma angiotensinogen levels could increase the sensitivity to other blood pressure stressors.

Methods

Male transgenic rats with a 9-fold increase of plasma angiotensinogen concentrations and male non-transgenic rats aged 10 weeks were treated or not with NG-Nitro-L-arginine-methyl ester for 3 weeks in their drinking water (n = 3/group). Systolic blood pressure and body weight were measured at baseline and at the end of the study when left ventricular weight and ventricular expression of angiotensin I-converting enzyme and procollagen Iα1 were determined (polymerase chain reaction).

Results

At baseline, transgenic rats had +18 mmHg higher bood pressure and –8% lower body weight compared to non-transgenic rats (P < 0.05) without significant changes for the vehicle groups throughout the study (P > 0.05). NG-Nitro-L-arginine-methyl ester increased blood pressure, left ventricular weight and left ventricular weight indexed for body weight by +41%, +17.6% and +18.6% (P < 0.05) in transgenic and +25%, +5.3% and +6.7% (P > 0.05) in non-transgenic rats compared to untreated animals, respectively. Cardiac gene expression showed no differences between groups (P > 0.05).

Conclusion

Increased plasma angiotensinogen levels may sensitize to additional blood pressure stressors. Our preliminary results point towards an independent role of angiotensinogen in the pathogenesis of human hypertension and associated end-organ damage.     

Morphological and immunocytochemical heterogeneity of cultured pinealocytes from one-week-and two-month-old rats: Planimetric and densitometric investigations

Abstract: In vitro preparations of rat pinealocytes are widely used for biochemical analyses of signal transduction processes. This paper deals with morphological and immunocytochemical features of such preparations. Special attention was paid to the problems of whether pinealocytes represent a heterogeneous cell population and how such heterogeneity may develop during ontogeny. The investigations were performed with cells which were obtained from the pineal organ of one-week-and two-month-old rats, attached to synthetic peptide-coated coverslips or tissue culture chamber slides, and maintained under in vitro conditions overnight. The attached cells were then fixed with paraformaldehyde. These preparations yielded monolayers of spherical cells of different sizes; most cells were isolated, but some of them were aggregated and formed small clusters. On the average, the cells from the one-week-old animals were smaller than the cells from the two-month-old animals. Immunocytochemical demonstration of S-antigen, a pinealocyte-specific marker, showed that the majority of the cells from two-month-old animals were intensely or moderately labelled. Pinealocytes from one-week-old animals were less S-antigen immunoreactive. Only very few cells (less than 1% displayed glial fibrillary acidic protein (GFAP)-immunoreactivity. Planimetric investigations of the cell size and semiquantitative densitometric investigations of the intensity of the S-antigen immunoreaction revealed that (i) pinealocytes kept in vitro form a heterogeneous cell population, and that (ii) this heterogeneity increases during postnatal development from one-week-old to two-month-old animals. Two groups of pinealocytes can be distinguished based on their developmental fate: pinealocytes of one group grow dramatically, but show only a moderate increase in S-antigen immunoreactivity, and pinealocytes of the other group retain their size, but display a distinct increment in S-antigen immunoreacti vitv.     

MUTATION FREQUENCY IN NURSES AND PHARMACISTS WORKING WITH CYTOTOXIC DRUGS

Individuals occupationally exposed to cytotoxic drugs may be at risk owing to the effects of these agents on DNA. As an index of DNA damage, in vivo mutations were measured in lymphocytes from 24 oncology nurses or pharmacists and 24 matched controls. Mutation frequency was significantly increased in exposed individuals and appeared to be related to duration of exposure. However, the overall magnitude of the increase was small and its biological significance remains to be determined.