Brain Banking for Research into Neurodegenerative Disorders and Ageing / 神经科学通报·英文版

Advances in cellular and molecular biology underpin most current therapeutic advances in medicine. Such advances for neurological and neurodegenerative diseases are hindered by the lack of similar specimens. It is becoming increasingly evident that greater access to human brain tissue is necessary to understand both the cellular biology of these diseases and their variation. Research in these areas is vital to the development of viable therapeutic options for these currently untreatable diseases. The development and coordination of human brain specimen collection through brain banks is evolving. This perspective article from the Sydney Brain Bank reviews data concerning the best ways to collect and store material for different research purposes.

Hegazy’ Simplified Method of Tissue Processing (Consuming Time and Chemicals).

Background: Processing is the next step in the histological process after tissue fixation. There are three methods commonly used for such tissue processing. They are the routine manual, rapid manual and the microwave methods. This study aimed to proceed a simple new manual method in a trial to take the advantages of rapid manual and microwave methods and avoid their disadvantages. Methods: One hundred samples of different tissues and cell blocks were included in this study. They were divided into two equal halves. One half is processed by the routine manual method and the other managed by new suggested technique. Results: The time consuming in the new method was about 7 hours vs. 20 hours in the routine processing. Also, the histologic quality was better in the new method as compared to the routine manual technique. Conclusions: The current simplified method of tissue and cell block processing using mild temperature and moderate agitation possess the advantages of reduction of time of processing, as well as the economic benefit of the utilization of fewer fluids.

Histo-architechtural Evaluation of Conventional Versus Two Rapid Microwave Processing Techniques.

Aims: This work aims to reduce the time of tissue processing, exclude xylene from tissue processing as well as to reduce the total quantity of reagents used per cycle of paraffin wax processing technique. Study Design: Harvesting and fixation of tissues. Grossing into triplicates, processing using three different techniques. Staining and grading of sections. Place and Duration of Study: Apparently healthy rabbits from the animal house, National Veterinary research Institute, Vom, Jos, Nigeria, between August and December, 2014. Methodology: Two apparently healthy rabbits were sacrificed and the Trachea, Lungs, Heart, Liver, Kidney, Stomach, Skin, Brain, and the Spleen were harvested and fixed in 10% buffered formalin for three days. They were grossed into triplicates, labeled and processed using the conventional, microwave without vacuum and microwave with vacuum respectively. They were sectioned and stained simultaneously using the haematoxylin and eosin staining technique as well as the Gordon and Sweet’s method. They were graded as excellent if they permitted microscopy, fair if not very good but can permit microscopy and poor if they cannot permit microscopy at all. Results: There is a drastic reduction in the duration of processing as well as the quantity of reagents used in the microwave techniques as compared to the conventional method. Xylene was completely eliminated in the microwave techniques. Tissue histo-architechture, special features as well as silver impregnation were clearly demonstrated without significant differences. Dye uptake as well as section thickness were comparable among the three techniques. Conclusion: Same-day turn-around is possible in histology, with reduced reagent consumption and elimination of xylene, without compromising section quality, dye uptake or ability to reduce silver to its metallic form. This will result to quick diagnosis hence quick intervention at a cheaper rate to both laboratories and clients. It is a good innovation in forensic and diagnostic histopathology and should be encouraged. Its compatibility with histochemical, immunohistochemical and molecular techniques should be evaluated to give a wider application.

A comparative study on microwave and routine tissue processing.

Aim and Objective: The present study was aimed at assessing the rapid microwave-assisted tissue processing and staining to determine if it can replace standard formalin-fixed and paraffin-embedded processing and staining technique. Materials and Methods: The study group consisted of 15 oral mucosal biopsies. The specimens were fixed in 10% formalin for 24 hours to ensure adequate fixation and their gross features were recorded, photographed, and then the specimens were cut into equal halves to be processed by both conventional and microwave histoprocessing methods and then subsequently stained with H and E by microwave and conventional methods. The stained slides in each group processed by both microwave and routine methods were randomly numbered for a blind study and circulated among six observers. All the observers were asked to grade each parameter into Excellent/Good/Average/Poor in a data sheet comprising a total of six parameters. These gradings were given a numerical value of 4, 3, 2 and 1, respectively. The parameters included in the data sheet were cellular clarity, cytoplasmic details, nuclear details, color intensity, interface of epithelium and connective tissue. Wilcoxon-matched pairs signed rank test (non-parametric) was used to calculate the test of significance (P value). Results: The total processing time involved in microwave was 42 minutes and 270 minutes for the conventional method. H and E staining in microwave took 33 minutes and 40 minutes for conventional method. Conclusions: The individual scores by different observers regarding the various parameters included in the study were statistically insignificant, the overall quality of microwave-processed and microwave-stained slides appeared slightly better than conventionally processed and stained slides.

Selection and evaluation of the methods of tissue processing on mucosa tissue from small intestine transplantation / 肠外与肠内营养

Objective: To improve the limitation and stability of tissue processing on mucosa from small intestine transplantation and to provide better evidence of pathological diagnosis for the acute rejection on small intestine transplantation. Method:92 samples of mucosa from small intestine transplantation were reviewed.There were three methods of tissue processing (ultrasonic wave and microwave as well as routine) were adopted.The results were analyzed with statistical methods. Results: Among 18 samples processed by the method of ultrasonic wave,4 samples were A grade (22.22%). Among 50 samples processed by the method of microwave,30 samples were A grade (60.00%). Among 24 samples processed by the method of routine,13 samples were A grade (54.17%).The Chi Square Test suggested that there was statistic difference among three processing methods. Conclusions: Microwave is the best method of tissue processing on mucosa of small intestine transplantation and for the diagnosis acute rejection.

Cryopreservation of Cardiovascular Tissue

Since Dr. Angell introduced cryopreservation method for tissue preservation in 1980s, it became a preferred method for cardiovascular tissues. Cryopreservation has been proven to provide better cell viavility and clinical result than any other preservation method. The quality of cryopreserved cardiovascular tissue is a very critical point of patients' survival when transplanted. To obtain high quality cryopreserved tissue, each processing methods from harvesting to delivery should be standardized. Various factors, such as range of possible tissues, acceptable ischemic time, temperature during transportation, facility for processing, method of freezing, use of cryoprotectant, method of storage, condition of delivery, and method of thawing for cardiovascular tissues should be standardized. Different standards should be established and applied to different tissues. Various kinds of tissues can be harvested from each living or cadaveric donor. Therefore, it is reasonable to harvest and handle all tissues in one laboratory by one tissue bank. In U.S.A, tissue banks are operated under standardized condition. The American Association of Tissue Banks affords the certification of specialist and tissue banks on very strict conditions, and provides the Food and Drug Administration with consultation in making regulations regarding tissue transplantation. In Korea, tissues have been simply stored in refrigerator since mid 1990s, and cryopreservation method is getting popular. Tissue banking has been started recently and now six major hospitals treat the cardiovascular tissues and are equipped with good facilities. Korean Association of Tissue Banks was established last year and now setting up regulations and standards. In Conclusion, I suggest that the cardiovascular tissue bank should belong to a university hospital till regulations and standards are completed. And then commercial tissue bank will be able to take it over to manage more tissues. The financial state of tissue banking is also an important point to be considered to balance between quality control and easy access to the public. Also the cost of cryopreserved allograft should be covered by medical insurance.