56℃孵育30min处理全血样本对红细胞血型抗原及血清抗体影响

探讨56℃孵育30min处理全血样本对红细胞血型抗原凝集强度及其抗体效价的影响,以降低传染风险,提高生物安全系数。方法 随机抽取衡水地区2022年6月-2023年1月期间共756例,其中来自无偿献血者血液样本200人份及来站检测的疑难血型鉴定及交叉配血的患者样本52人份,共252人份。将同一人份样本分为三组:对照组、灭活组-1、灭活组-2各252例。其ABO血型分布情况为 :A型61人份,B型60人份,AB 型61人份,O型60人份,ABO亚型10人份;其RhD血型分布情况为:RhD阳性235人份,D变异型13人份, RhD阴性4人份;直接抗球蛋白试验(简称直抗)分布情况为:直抗阳性样本32人份,直抗阴性样本220人份。经56 ℃孵育后,检测正反定型试验,抗A,抗B、意外抗体效价变化。结果 离心样本经56℃孵育30min后,红细胞平均溶血率为0.24%±0.08%;红细胞表面A、B、D抗原凝集强度变化不大,孵育后血清中抗-A、抗-B、意外抗体效价影响不大。结论 对于抗体筛查试验阴性,直抗阴性,正反定型相符的血样,56℃孵育30min处理血样,抗筛仍为阴性,正反定型相符。

人血液经56℃孵育处理后溶血率及血型抗原抗体变化

目的为降低传染风险,对疑似或确诊新型冠状病毒(SARS-Cov-2)患者血样,部分实验室采用56℃孵育30分钟后再进行血型血清学检测,该处理方法对输血前检测的影响未见评估研究。本研究对血液样本经56℃孵育后的溶血率、红细胞A、B、D抗原凝集强度及其抗体效价进行评估。方法从上海地区随机抽取正常献血者A型20例,B型20例,AB型10例,O型20例,均为RhD阳性;ABO亚型7例,D变异型6例,经56℃孵育后,检测游离血红蛋白水平,评估溶血率;正定型试验,抗原抗体中和试验,抗体效价试验评价A、B、D抗原凝集强度及抗A,抗B效价变化。结果经56℃孵育处理后,红细胞平均溶血率为1.87%±2.02%;血清学红细胞表面A、B抗原凝集强度均存在减弱现象,正常D阳性个体的D抗原未见减弱,D变异型个体D抗原存在减弱现象;孵育后血清中抗-A、抗-B抗体效价降低。结论血液样本经56℃孵育后,均有较低程度溶血,溶血程度不影响血型血清学实验;A、B抗原与抗-A、抗-B抗体均有减弱,但减弱的程度不足以干扰实验室常规血型正反定型试验;ABO亚型抗原在定型试验中可能受到影响。

Effects of Temperature on Determination of Protein Concentration with Coomassie Brilliant Blue Method

[Objective] This study aimed to investigate the effects of temperature on determination of protein concentration with Coomassie Brilliant Blue method,thus proving advice and guidance for accurate determination of protein concentration.[Method] With Coomassie Brilliant Blue method,the concentrations of different bovine serum albumin samples were determined under different temperatures and incubation time.[Result] According to the standard curve,when the determination range of protein concentration was 0-100 mg/ml,the determined protein concentration was relatively stable after incubation at 20 ℃ for 20-30 min.Furthermore,the determination result of higher protein concentration with Coomassie Brilliant Blue method was less affected by various factors.[Conclusion] In determination of protein concentration with Coomassie Brilliant Blue method,temperature,sample concentration and incubation time were important factors affecting the accuracy of experimental results.

Research on Embryonic Development of Loach

[Objective] Aim to know the whole process of embryonic development of loach. [Method] DOM + LHRH-A2 was used to induce spawning of loach,then after fertilization,the embryos were cultured into freshwater water with temperature from 24 to 26 ℃ and pH from 7.0 to 7.5. The embryonic development of loach was observed and 27 concrete morphological characteristics and development time of loach from fertilized egg to newly hatched larval period were described in detail. [Result] The embryonic development of loach could be divided into cleavage stage,blastocyst stage,gastrula stage,neurula stage and organogenesis stage. The loach embryo from fertilized egg to out membrane period was 30 h 45 min in fresh water from 24 to 26 ℃ and pH from 7.0 to 7.5. [Conclusion] It provided important reference for studying artificial propagation and genetic breeding of loach.

Morphological changes and allometric growth in hatcheryreared Chinese loach Paramisgurnus dabryanus(Dabry de Thiersant, 1872)

The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach, Paramisgurnus dabryanus(Dabry de Thiersant, 1872), were determined from hatching to 60 days after hatching. A best power model was estimated for the length-weight relationship during the early life stages. Positive allometric growth for the head segment, trunk length, tail length and eye diameter was also found in the early life stages, while body depth, tail depth, tail fi n length, pectoral fi n length and barbel length displayed a negative coeffi cient. During the subsequent early developmental stage, the growth coeffi cients showed a clear and common tendency towards isometry for all measured body ratios. The allometric growth changes in Chinese loach during the early stage are possibly the result of selective organogenesis directed towards survival priorities.

Effects of temperature and salinity on the development of embryos and larvae of the veined rapa whelk Rapana venosa(Valenciennes, 1846)

The major population of the veined rapa whelk Rapana venosa （Valenciennes, 1846）, which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature （16-34℃ at salinity 30） and salinity （5-45 at 25℃） on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34℃, the lower temperature limit was 16~C, the longest mean shell length （1 193＋17 pan） occurred at 25℃ and the highest survival rate 72.28%＋5.62% was observed at 28℃. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15-40, the longest mean shell length （855-4-9 μm） and the highest survival rate 72.93%~4.85% were both observed at 35. This study demonstrated that, during the egg-mass stage, temperature and salinity regimes influence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa.

Shape change in viable eggs of the collembolan Folsomia candida provides insight into the role of Wolbachia endosymbionts

The endosymbiotic bacteria of the genus Wolbachia that infect the collembolan species Folsomia candida are responsible for facilitating parthenogenetic reproduction in their hosts. This study made empirical observations of the development of eggs of F. candida which contained normal populations of Wolbachia and of eggs which were cured of Wolbachia by treatment with the antibiotic rifampicin. A marked increase in egg size accompanied by a significant change in shape from spherical to discoid occurred in viable eggs three to four days after laying. These changes did not occur in the universally inviable eggs which came from the antibiotic treatment or in the 7% of untreated eggs which were naturally inviable. We infer that Wolbachia plays a critical role in zygotic or embryonic development during or before the first three days after laying and we draw on existing knowledge in speculating on the developmental mechanisms that Wolbachia may influence.

Embryonic and larval development in barfin flounder Verasper moseri (Jordan and Gilbert)

Broodstock of Verasper moseri （Jordan and Gilbert） aged 3-4 years old were selected, and reinforced cultivation was conducted to promote maturation under controlled water temperature and photoperiod conditions. Fertilized eggs were obtained by artificial fertilization, and the development of embryos, larvae and juveniles was observed continuously. The results showed that the fertilized eggs of V. moseri were spherical, with transparent yolk and homogeneous bioplasm, and had no oil globule inside. The average diameter of the eggs was 1.77＋0.02 mm. The eggs of V. moseri were buoyant in water with salinity above 35. The cleavage type was typical discoidal. Young pigment cells appeared when olfactory plates began to form. Hatching occurred at 187 h after fertilization at a water temperature of 8.5℃. The newly hatched larvae, floating on the water surface, were transparent with an average total length of 4.69±0.15 mm. During the cultivation period, when the water temperature was raised from 9 to 14.5℃, 4-day old larvae showed more melanophores on the body surface, making the larvae gray in color. The pectoral fins began to develop, which enabled the larvae to swim horizontally and in a lively manner. On days 7-8, the digestive duct formed. The yolk sac was small and black. The yolk sac was absorbed on day 11. Larvae took food actively, and body length and body height clearly increased. The rudiments of dorsal and anal fin pterygiophores were discernible and caudal fin ray elements formed on day 19. On day 24, the larval notochord flexed upwards, and the rays of unpaired fins began to differentiate. Pigment cells converged on the dorsal and anal fin rays, and the mastoid teeth on the mandible appeared. On day 29, the left eyes of juveniles began to move upwards. Depigmentation began in some juveniles and they became sandy brown in color on day 37. Most juveniles began to settle on the bottom of the tank. The left eyes of juveniles migrated completely to the right side on day 50, when the average body length attained 2.5±0.18 cm, and juveniles accomplished metamorphosis to young. The embryonic and larval characters of several flounder species are compared.

The Breeding Status of the Glossy Ibis Plegadis falcinellus in the Lebna Dam in Cap Bon, Tunisia

The study of the reproduction of the Glossy Ibis （Plegadisfalcinellus） in Tunisia was undertaken from 2008 to 2010. Until the discovery of nesting in 2008, this species had only been considered as wintering in Tunisia. The Tunisian breeding population resides in the Lebna Dam in the north east of the country where it forms a mixed nesting colony with other species of the family Ardeidae （（Bubulcus ibis （Bi）： 388 pairs, Ardeola ralloides （Ar）： 17 pairs, Egretta garzetta （Eg）： 27 pairs）, （Bi： 300 pairs, At： 25 pairs, Eg： 40 pairs） and （Bi： 400 pairs, Ar： 30 pairs, Eg： 10 pairs） recorded in 2008, 2009 and 2010 respectively）. All nests were constructed on Acacia horrida. Laying began in early May. The average clutch size over the three years of the study was 3.44 ± 0.73 eggs （N = 29 nests）. Hatching success was 83 % （2.86 ± 1.18 eggs hatched/nest） and 2.65 ± 1.17 hatchlings/nest survived until the age of 10 to 12 days. Egg mortality was 17% during the incubation phase and chick mortality was 7.2%. No interannual variation was detected in these parameters.

Nominal effective immunoreaction volume of magnetic beads at single bead level

Immunomagnetic bead（IMB）-based enzyme-linked immunosorbent assay（ELISA） has been the tool frequently used for protein detection in research and clinical laboratories.For most ELISA reactions the recommended dosage of IMBs is usually according to their weight（mg） or mass fraction（w/v） instead of the bead number.Consequently, the processes occurring in the immediate vicinity of the IMBs have always been ignored by researchers and they cannot be revealed in detail during the ELISA reaction.In this paper, we established the relationship between number of IMBs and colorimetric results, and further proposed a new concept of ＂nominal effective immunoreaction volume（NEIV）＂ to characterize a single IMB during ELISA reaction.Results showed that the NEIV of a single IMB has a constant value, which is unrelated to the amount of beads and the concentration of antigen.Optimal results of the colorimetric ELISA are achieved when the incubation volume meets each IMB＇s NEIV and is no longer enhanced by increasing the incubation volume.Thus, the reliable and relatively precise number of IMBs for ELISA detection during practical application could be determined.Most importantly, a study using IMB＇s NEIV would lay the foundation for a kinetics analysis of IMBs and antigens for future study.