A new technique for the culture of fern gametophytes

Fern gametophytes initiated from spores grew successfully when immobilised in reticulate polyurethane foam in liquid shake cultures. Colonisation of this matrix was complete seven days after medium inoculation and appeared to be a completely passive process. Yield (dry weight) was greater than that from liquid grown cultures.     

脊髓薄片器官型培养的方法研究（简报）

脊髓的器官培养技术是借助体外培养技术,将脊髓或其一部分分离出来进行培养、研究的技术。因其保留有脊髓神经元及其周围的组织结构,与体内的生理环境相似,是探讨脊髓形态发生、构筑特点、生理功能及病理改变等问题的一条重要途径,在近年来得到飞速发展,成为国际神经科领域的一大研究热点。本文旨在利用脊髓薄片器官型培养技     

Culture of fetal mouse liver in plastic chambers: A new technique for organ culture

Summary A new technique for organ culture which uses plastic culture chambers and the advantages of the cellophane-sheet technique is described with the results of a study of cultivations of fetal mouse liver. Two chambers, each containing cells, were placed in gas permeable roller tubes and rotated at 0.1 rpm in a CO₂-air gassed incubator. The fetal mouse liver cells developed electron microscopic features similar to those of the in vivo adult liver by 9 days of cultivation. The albumin content and tyrosine aminotransferase (TAT) activity were detected in the cultivated liver. TAT activity was further induced by prednisolone. These results indicate the potential of this culture method for the study of physiological and pathological processes. This work was supported in part by a Grant-in-Aid for Cancer Research from the Ministry of Education, Science and Culture, Japan and Science Technology Agency, Japan.     

红花草莓的组织培养与快繁技术研究

以红花草莓叶片为外植体,通过筛选诱导愈伤组织、不定芽及壮苗、生根的培养基,建立一套实用且易推广的红花草莓组培快繁技术体系。结果表明:在愈伤组织的诱导过程中TDZ的诱导效果优于6-BA,TDZ与NAA配合使用效果优于与IBA的组合。6-BA浓度为0.5 mg·L~(-1)时不定芽诱导率高达86.6%。低浓度的6-BA和8 g·L~(-1)的琼脂更有利于壮苗培养,NAA比IBA更有利诱导生根。综上述,最适红花草莓愈伤组织的诱导培养基为MS+1.0 mg·L~(-1)TDZ+0.5 mg·L~(-1)NAA+30 g·L~(-1)蔗糖+7 g·L~(-1)琼脂;最适不定芽分化的培养基为MS+0.5 mg·L~(-1)6-BA+0.1 mg·L~(-1)NAA+30 g·L~(-1)蔗糖+7 g·L~(-1)琼脂;最适壮苗培养基为MS+0.1 mg·L~(-1)6-BA+0.1 mg·L~(-1)NAA+30 g·L~(-1)蔗糖+8g·L~(-1)琼脂;最适生根培养基为MS+0.5mg·L~(-1)NAA+30 g·L~(-1)蔗糖+8 g·L~(-1)琼脂。试管苗移栽生长20 d后,成活率高达93%,且后期草莓苗生长壮健。此体系的建立为优质红花草莓种苗大规模生产提供了科学依据和技术支持。     

Type II alveolar cells in organotypic culture: A model system for the study of surfactant synthesis

• 1.1. Type II cells, maintained in an organotypic system where in vivo morphologic characteristics are retained, were utilized to study surfactant phospholipid and protein synthesis. Cellular components were separated into a surfactant and a residual fraction by sucrose density centrifugation. The major phospholipid of the surfactant fraction is phosphatidylcholine (70%). Phosphatidylglycerol accounts for 4.0% of the total surfactant phospholipids. Phosphatidylcholine is also the major phospholipid of the residual fraction, constituting 50% of this fraction's phospholipids; phosphatidylglycerol is also present (4.2%).
• 2.2. Type II cells in organotypic culture are capable of metabolizing exogenous glucose. The uptake of glucose from the incubation medium is concentration dependent. Glucose can be utilized by the type II cell for surfactant and residual phosphatidylcholine synthesis. The rate of incorporation of glucose into residual phosphatidylcholine is three times the incorporation rate into surfactant phosphatidylcholine.
• 3.3. Palmitate and choline can also be utilized for surfactant and residual phosphatidylcholine synthesis. Palmitate incorporation into residual phosphatidylcholine is five times greater than the incorporation into surfactant phosphatidylcholine. Surfactant phosphatidylcholine is labelled with choline at a rate one-fourth that of residual phosphatidylcholine. In contrast to glucose and palmitate, choline incorporation into surfactant phosphatidylcholine is linear only after a 15 min lag period. The labelling of residual phosphatidylcholine with choline is biphasic.
• 4.4. Type II cells in organotypic culture can also synthesize the protein moiety of surfactant. Leucine was found to incorporate linearly into surfactant proteins for approx. 8 h.

     

A new technique for brachioplasty

A new technique for brachioplasty is proposed, aiming at correction of ptosis without excision. It is based on rolling a deepithelialized flap around from the rear and sliding it underneath the inside frontal skin of the arm, recreating the roundness of the arm and a firmer consistency. This technique has been utilized in 12 patients so far, with a follow-up ranging from 8 months to 4 years. No postoperative edema were observed, but one case of hyperesthesia appeared for a period of 2 months. The main preoccupation is scar sequelae, which must limit the intervention to patients clearly aware of the possibility of healing complications.     

A new role for the sieve plate

The sieve plate may act as an anchor for the plasmalemma preventing its disruption by the viscous drag of the flowing sieve tube sap. This function is envisaged as being probably in addition to some of the other functions for the sieve plate already suggested by various workers.     

A two-centre evaluation of the human organotypic skin explant culture model for screening contact allergens

Animal models are considered to be the "gold standard" for determining the potential contact allergenicity of low molecular weight chemicals. However, governmental regulations and ethical considerations limit the use of animals for such purposes. There is therefore a need for in vitro alternative models. The human organotypic skin explant culture (HOSEC) model is reported to be a promising alternative method for the predictive testing of contact allergens. The accelerated migration of Langerhans cells from the epidermis upon exposure to contact allergens is used to identify chemicals that are potentially capable of inducing a delayed-type hypersensitivity. In the study described in this paper, the model was further refined, and used, in two independent laboratories, to screen 23 low molecular weight compounds of known classification for their allergenicity. Each laboratory was able to accurately detect the contact allergens, despite small variations in the protocols used. However, the classification of dermal irritants, which have often been falsely classified as allergens, varied between the two laboratories. Despite the current limitations of the HOSEC model, the accuracy of the predictions made (sensitiser or non-sensitiser) compare favourably with classifications obtained with commonly used animal models. The HOSEC model has the potential to be developed further as an in vitro alternative to animal models for screening for contact allergens.