粪便中双歧杆菌和大肠杆菌含量对肝癌患者预后的预测价值分析

摘要 目的：探讨与分析粪便中双歧杆菌和大肠杆菌含量对肝癌患者预后的预测价值。方法：研究时间为2016年12月到2019年12月,采用回顾性研究方法,选择在本院重症监护病房(Intensive Care Unit,ICU)诊治的肝癌患者78例作为研究对象,检测粪便中双歧杆菌和大肠杆菌含量,调查患者的预后并进行预测价值分析。结果：在78例患者中,死亡18例,死亡率为23.1 %。存活组与死亡组的性别、年龄、体重指数、白细胞(white blood cell,WBC)、血小板(Platelets,PLT)计数计数等对比差异无统计学意义(P>0.05),两组的急性生理学及慢性健康状况评分系统(acute physiology andchronic health evaluation scoring system,APACHE Ⅱ)评分、临床分期等对比差异有统计学意义(P<0.05),死亡组的血清甲胎蛋白(?琢-fetoprotein,AFP)值显著高于存活组(P<0.05)。死亡组的双歧杆菌含量与双歧杆菌/大肠杆菌比值低于存活组,大肠杆菌含量高于存活组,对比差异都有统计学意义(P<0.05)。直线相关分析显示患者预后死亡与双歧杆菌/大肠杆菌比值、AFP、APACHE Ⅱ评分、临床分期有相关性(P<0.05)。双歧杆菌/大肠杆菌比值对肝癌患者预后死亡的预测ROC曲线下总面积为0.865。结论：肝癌患者预后死亡患者多伴随有粪便中菌群失衡状况,粪便中双歧杆菌和大肠杆菌含量能很好预测肝癌患者的预后。     

粪便中肠球菌SYBR GreenI荧光定量PCR检测方法的建立

目的利用SYBR GreenI荧光定量PCR方法,建立肠球菌实时荧光PCR检测方法,并初步应用于粪便中肠球菌的检测。方法根据GenBank发表的肠球菌23S rRNA基因序列的保守区域设计合成特异性的引物;利用构建的质粒标准品绘制两种标准曲线,构建基因拷贝数、细菌数为分析指标的定量分析模型并初步应用于粪便标本的检测分析。结果所建立的SYBR GreenI荧光定量PCR方法检测灵敏度可达7个拷贝数/reaction。粪便样本根据实时荧光定量PCR方法所得的理论数值与培养菌值之间差异无显著性(P>0.05)。非炎性腹泻标本中菌数与健康成人标本中菌数差异无显著性(P>0.05)。灵敏度曲线所得的数值大于菌数标准曲线,可能由于DNA提取过程中存在部分的损失。检测粪便标本结果显示SYBR GreenI荧光定量PCR方法较平板计数法敏感、快捷、简便。结论本研究建立了一种灵敏、特异、简便易行的肠球菌定量检测方法。     

Measurement of phenol and p-cresol in urine and feces using vacuum microdistillation and high-performance liquid chromatography

In this article, we describe a simple, sensitive, accurate, and repeatable method for the measurement of phenol and p-cresol (4-methylphenol) in human urine and feces. We examined a number of parameters to identify an optimal extraction protocol. Purification of sample extracts was achieved by low-temperature vacuum microdistillation. Separation was achieved in approximately 15 min by high-performance liquid chromatography (HPLC) with quantification by fluorescence at 284/310 nm. Limits of detection for phenol were 2 ng/ml for urine and 20 ng/g for feces, and those for p-cresol were 10 ng/ml for urine and 100 ng/g for feces. For comparison, approximate mean values for urine are 3 μg/ml for phenol and 30 μg/ml for p-cresol, and those for feces are 1 μg/g for phenol and 50 μg/g for p-cresol. An experienced analyst can process 60 samples each day using this method.     

Organic matter processing by the shrimp Palaemonetes sp.: Isotopic and elemental effects

Aquatic crustaceans often play a major role in organic matter (OM) transformation and recycling through their feeding and excretory activities. In this study, we measured the isotopic and elemental composition of organic matter fed to Palaemonetes sp. shrimp and the fecal pellets they produced. Nitrogen (N) content of the food (8.2 ± 0.2%, mean ± SD) was significantly higher than the fecal pellets (2.0 ± 0.9%), a pattern that also applied to the carbon (C) content of food (46.7 ± 1.0%) and fecal pellets (14.3 ± 6.8%). We also found a significant decrease in the N content of undigested, macerated food (6.1 ± 0.9 %) relative to food that had been soaked in artificial seawater (ASW) and artificial seawater that had previously contained shrimp (CASW) in the absence of feeding shrimp. We found no significant difference in N or C isotopic composition between the dry food, ASW- and CASW-soaked control food, and fecal pellets. We did, however, observe a significant increase in δ¹⁵N of the undigested, macerated food (δ¹⁵N = 6.3 ± 0.6‰) relative to both the dry flake food (δ¹⁵N = 5.6 ± 0.2‰) and controls incubated in the absence of shrimp in either ASW (δ¹⁵N = 5.6 ±0.3‰) or CASW (δ¹⁵N = 5.8 ± 0.1‰). Our results differ from previous findings of isotopic alteration of OM during processing by crustaceans (copepods), suggesting that isotopic changes related to feeding might be either taxon- or food-specific. This study also provides information on the influence of grazers/shredders on both the elemental and isotopic composition of POM, suggesting that larger aquatic shredders can influence the chemical composition of particles by either physical manipulation of the POM (release of DOM) or by facilitating microbial colonization of the POM.     

Fecal 20-oxo-pregnane concentrations in free-ranging African elephants (Loxodonta africana) treated with porcine zona pellucida vaccine

Because of overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. In this regard, the potential use of the porcine zona pellucida (pZP) vaccine as an effective means for population control is explored. While potential effects of pZP treatment on social behavior of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. In this study, ovarian activity of free-ranging, pZP-treated African elephant females was monitored noninvasively for 1 yr at Thornybush Private Nature Reserve, South Africa, by measuring fecal 5α-pregnan-3β-ol-20-on concentrations via enzyme immunoassay. A total of 719 fecal samples from 19 individuals were collected over the study period, averaging 38 samples collected per individual (minimum, maximum: 16, 52). Simultaneously, behavioral observations were made to record the occurrence of estrous behavior for comparison. Each elephant under study showed 5α-pregnan-3β-ol-20-on concentrations rising above baseline at some period during the study indicating luteal activity. Average 5α-pregnan-3β-ol-20-on concentrations were 1.61 ± 0.46 μg/g (mean ± SD). Within sampled females, 42.9% exhibited estrous cycles within the range reported for captive African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average estrous cycle duration was 14.72 ± 0.85 wk. Estrous behavior coincided with the onset of the luteal phase and a subsequent rise in 5α-pregnan-3β-ol-20-on concentrations. Average 5α-pregnan-3β-ol-20-on levels positively correlated with rainfall. No association between average individual 5α-pregnan-3β-ol-20-on concentrations or cyclicity status with age or parity were detected. Earlier determination of efficacy was established via fecal hormone analysis with no pregnancies determined 22 mo post-treatment and onward. Results indicate the presence of ovarian activity amongst pZP-treated female African elephants in 2 yr after initial immunization. Further study should now be aimed toward investigating the long-term effects of pZP vaccination on the reproductive function of female African elephants.     

Fecal corticosteroids in a territorial bird selected for different personalities: daily rhythm and the response to social stress

In this study we tested the hypothesis that in a passerine bird (great tit, Parus major) individuals differing for coping strategies differ in the magnitude of the adrenocortical response to social stress as well. Furthermore, we aimed at characterizing daily rhythms in corticosteroid release before and after social stress. We used 16 males from either of two lines bidirectionally selected for different coping strategies (fast and slow explorers). Social stress was induced by confrontation with an aggressive resident male. Corticosteroid metabolites were analyzed in feces collected at 90-min intervals from 900 to 1630 h on a baseline day, on the day of the social conflict, and on the following day. In both days and in both lines levels varied with time of day in a robust rhythm with a peak in the first sample of the morning and a trough at the end of the light phase. This rhythm correlates with activity (perch hopping). An overall increase in levels relative to baseline day was observed between 30 and 140 min after the challenge. Birds of the less aggressive and more cautious line (slow explorers) showed a trend for a higher response compared to birds of the more aggressive and bolder line (fast explorers), which showed almost no response. On the day after the challenge the birds of the slow line exhibited significantly reduced corticosteroid secretion, probably due to an increased negative feedback. The results provide evidence for a physiological basis of different coping strategies in birds, emerging in response to social stress and with a pattern similar to that in other vertebrates.     

Analyzing corticosterone metabolites in fecal samples of mice: a noninvasive technique to monitor stress hormones

In small animals like mice, the monitoring of endocrine functions over time is constrained seriously by the adverse effects of blood sampling. Therefore, noninvasive techniques to monitor, for example, stress hormones in these animals are highly demanded in laboratory as well as in field research. The aim of our study was to evaluate the biological relevance of a recently developed technique to monitor stress hormone metabolites in fecal samples of laboratory mice. In total, six experiments were performed using six male and six female mice each. Two adrenocorticotropic hormone (ACTH) challenge tests, two dexamethasone (Dex) suppression tests and two control experiments [investigating effects of the injection procedure itself and the diurnal variation (DV) of glucocorticoids (GCs), respectively] were conducted. The experiments clearly demonstrated that pharmacological stimulation and suppression of adrenocortical activity was reflected accurately by means of corticosterone metabolite (CM) measurements in the feces of males and females. Furthermore, the technique proved sensitive enough to detect dosage-dependent effects of the ACTH/Dex treatment and facilitated to reveal profound effects of the injection procedure itself. Even the naturally occurring DV of GCs could be monitored reliably. Thus, our results confirm that measurement of fecal CM with the recently established 5alpha-pregnane-3beta,11beta,21-triol-20-one enzyme immunoassay is a very powerful tool to monitor adrenocortical activity in laboratory mice. Since mice represent the vast majority of all rodents used for research worldwide and the number of transgenic and knockout mice utilized as animal models is still increasing, this noninvasive technique can open new perspectives in biomedical and behavioral science.     

Morphometric analyses of non-invasive fecal samples of the Korean long-tailed goral (Naemorhedus caudatus) for species and age identification

The Korean long-tailed goral (Naemorhedus caudatus) is at risk of population decline due to habitat loss and fragmentation. Therefore, it is essential to ascertain its presence and/or the identity of individuals of the goral using non-invasive fecal samples for its conservation and management. In this study, we examined the morphology of fecal samples to provide the baseline data that can be used to distinguish species and age of goral individuals. We detected a significant difference in the length-to-width ratios of feces among the five ungulate species found in Korea. Also, we detected a significant difference in the length-to-width ratios of feces of gorals depending on the age groups. To assess the accuracy of species and age identification based on the fecal morphology, we conducted a series of blind comparison between the mean length-to-width ratios of the fecal pellets and the reference mean ratio values of the fecal pellets. Using 20 fecal pellets, our results showed 73%–86% probability of correct identification of the three species (gorals, goats, and roe deer), and 83%–90% probability of correct identification of >5 year-old goral individuals. The use of fecal morphometric analyses will be useful for the studies of Korean ungulate species, particularly the endangered gorals.     

The role of the sea urchin,Tripneustes gratilla (Linnaeus), in decomposition and nutrient cycling in a tropical seagrass bed

The sea urchin,Tripneustes gratilla, which feeds mainly on living leaves of the seagrass,Thalassia hemprichii, was studied in its habitat on the southern coast of Papua New Guinea, and its roles in decomposition and nutrient cycling in a seagrass bed were assessed through the excretion of ammonium and metabolism of feces produced by the sea urchin. Carbon content of the fresh feces (21% of dry weight) was similar to that of intact dead leaves of the same species (22–23%). Carbon/nitrogen and carbon/phosphorus ratios of the feces (21.7 and 466, respectively), however, were significantly lower than those of the dead leaves (25.9–27.7 and 656–804, respectively), indicating that the feces retain more nitrogen and phosphorus in comparison with carbon. Net consumption of ammonium and orthophosphate typically concurred with oxygen consumption during dark incubation of both the dead leaves and the sea urchin feces. Compared with the same oxygen consumption rate, however, the dead leaves consumed more orthophosphate than the feces. Under sunlight, dead leaves showed a net accumulation of carbon by epiphytic algae, while the feces showed a carbon loss. Ammonium excretion by this sea urchin (1.7–5.4 mg nitrogen/individual/day) would thus appear to make a significant contribution to nitrogen recycling since biological communities associated with dead leaves and sea urchin feces tend to demand an external supply of nitrogen, such as ammonium.     

基于粪便DNA 的九龙山黑麂种群的遗传多样性

近年来,由于人类活动的干扰使黑麂的栖息地明显减少并呈斑块状分布。因此,深入了解该物种各地理分布种群的遗传现状是制定保护及管理策略的重要科学依据。本研究运用非损伤取样技术在浙江省九龙山国家级自然保护区的黑麂分布区共采集61 份粪便样品、2 份肌肉样品和2 份皮张样品,采用8 个特异微卫星位点对61 份粪便样品中提取的DNA 进行检测,肌肉和皮张样品DNA 的检测结果作为对照,分析了九龙山国家级自然保护区黑麂种群的遗传多样性。经多次重复提取和PCR 扩增后,发现61 份粪便样本中有38 份可被稳定扩增,且不同样本间的条带大小有较大差异,因此我们认为38 份粪便样本来源于38 只不同的黑麂个体。8 个微卫星位点共检测到50 个等位基因,平均等位基因数(A)为6 (5 ～ 8);平均有效等位基因数(Ne)为5. 297 (4.031 ～6.353);平均期望杂合度(He) 为0.817 (0.763 ～ 0.855);平均多态信息含量(PIC ) 为0. 775 (0.709 ～0.822)。8 个位点的平均个体识别率(DP)为0.931,累积个体识别率(CDP)为0.999 9。有1 个微卫星位点(BM1706)极显著地偏离了Hardy-Weinberg 平衡(P < 0.01)。以上结果显示该分布区黑麂种群具有较高的遗传多样性。