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This is the only half-day local tour in Brno that the ChatGPT has suggested.

FBS vs. hPL
Platelet vs. Platelet Lysate

人類脂肪細胞的壽命
Lifespan of a human adipocyte

Once again, the difference between Oncoplastic Surgery and Ni**le Sparing Mastectomy!

Introduction of Microfluidic System

Full text: Micromachines (Basel). 2020 Mar 11;11(3):297

“In science, predicting the significance and outcome of really new work eludes many of us.”

So wrote Rose Johnstone, PhD, in 2003, when she authored a history of the first 60 years of McGill’s Department of Biochemistry. The first (and as yet only) woman to chair that department, Johnstone is known for her discovery of exosomes, a key development that has advanced the field of cell biology.

Little did she know at the time, however, that nearly fifty years later her discovery of exosomes would take on new significance by enabling the development of entirely new kinds of medicines, and with considerable potential to transform the treatment of a wide range of diseases.

Born Rose Mamelak in Poland in 1928, she arrived in Montreal with her family in 1936. Initially speaking no English, she went on to graduate top of her class from Baron Byng High School. Encouraged by her feminist mother, Rose enrolled at McGill, supporting herself with scholarships.

She majored in microbiology but soon switched to the emerging field of biochemistry. As she recalled in her 1984 autobiographical essay (Feeling Outside on the Inside), she had realized, “The study of the chemical elements in living systems filled me with excitement and interest beyond anything I had experienced before.”

A pioneer for women in science

She was awarded her PhD in 1953, the same year she married Douglas Johnstone. They moved to England for two years so she could pursue postdoctoral research. In 1961, she returned to McGill’s Department of Biochemistry as an assistant professor. Promoted to Associate Professor in 1967, she became Full Professor in 1977, and authored 132 peer-reviewed publications.

The first woman to hold the Gilman Cheney Chair in Biochemistry, Johnstone served as Chair of the Department of Biochemistry from 1980 to 1990 — the first woman to lead a basic science department at McGill, and only one of five in North America at that time.

A champion of equal pay for equal work in academia, she served on the Committee on the Status of Women at McGill, helping to challenge gender discrimination. Her son, Michael Johnstone, MDCM, established the Rose Mamelak Johnstone Research Bursary in her memory to encourage women to pursue a scientific career.

Discovery of exosomes

Through her work with red blood cells and iron uptake in the 1970s and 1980s, Johnstone and her research team discovered and named exosomes — vesicles that originate inside our cells to leave and carry proteins and genetic information between cells.

Her research showed that an iron-binding protein was absent from the surface of mature red blood cells. She identified a new vesicle structure that she named the exosome. She discovered that, through the exosome, iron-binding proteins leave reticulocytes (immature red blood cells), enabling the maturation of red blood cells. (Without iron, red blood cells cannot take up or deliver oxygen, and life ceases.)

Johnstone also discovered the unique pathway through which cells secrete exosomes, distinguishing them from other types of vesicles.

Exosomes are now recognized for their role in normal communication among cells in the immune system, the brain and the heart. They are also involved in neurodegenerative disease, liver disease, heart failure and cancer. Scientists had published more than 8,400 papers on exosomes since her discovery, according to the 2019 entry in the Canadian Encyclopedia. Astonishingly today, the number is 31,415 as indicated in the academic depository of peer-reviewed papers, PubMed.

Scientific societies, such as the American Society for Exosomes and Microvesicles and the International Society for Extracellular Vesicles, a journal (Journal of Extracellular Vesicles), databases (ExoCarta, Vesiclepedia) and a research portal (exRNA) are now dedicated to the field that Johnstone’s research helped to establish.

Today, exosomes are emerging as a promising way to deliver precision medicines.. They can be engineered to carry a variety of molecular cargoes, including proteins, lipids, DNA or RNA to recipient cells, making them an ideal vehicle for the delivery of therapeutic agents. This is particularly promising with regards to emerging modalities of RNA therapeutics, for example.

A force of nature

“Rose was a scientist’s scientist. I admired her,” says David Y. Thomas, Canada Research Chair in Molecular Genetics, who chaired the Department of Biochemistry from 2000 to 2013.

Thomas notes that Johnstone’s work provided a foundation for subsequent decades of vital biochemical research. He points to the current work of Janusz Rak, a McGill Professor of Pediatrics and Senior Scientist at the Research Institute of the McGill University Health Centre, whose research includes the study of exosomes and the interruption of intracellular connections in the progression of human cancers.

Another present-day example is the work of McGill alumnus Antonin (Tony) De Fougerolles, PhD, the CEO of Evox Therapeutics, a biotech company focused on “improving the natural delivery capabilities of exosomes and developing an entirely new class of therapeutics,” according to their website.

Notes Thomas Duchaine, PhD, Chair of McGill’s Department of Biochemistry and Director of the McGill Centre for RNA Sciences (MCRS), launched in 2022, “It’s thanks to the foundational work of scientists like Rose Johnstone that the MCRS is harnessing the tremendous potential of RNA functions in biotechnologies and treatments for a broad variety of human diseases.”

The road to curiosity-based science

In 2005, Johnstone authored a paper, “Revisiting the road to the discovery of exosomes.” In it, she describes the long, uncertain process of trial and error, as she and her team discovered, “these small structures, of relatively modest protein content.”

Her closing remarks reflect upon the nature of scientific exploration:

“It may take years for a newly described biological phenomenon to become more than a curiosity and its potential recognized. Once recognized, the growth of interest may be very rapid. Perhaps we are on the doorstep of this latter stage.”

“在科學領域，我們很多人都無法預測真正新工作的意義和結果。”

2003 年，羅絲•約翰斯通 (Rose Johnstone) 博士如此寫道，當時她撰寫了麥吉爾生物化學系前 60 年的歷史。約翰斯通是該部門第一位（也是迄今為止唯一一位）女性系主任，她因發現外泌體而聞名，這是推動細胞生物學領域發展的關鍵進展。

然而，她當時幾乎不知道，近五十年後，她對外泌體的發現將具有新的意義，能夠開發全新的藥物，並且具有改變多種疾病治療方法的巨大潛力。

她於 1928 年出生於波蘭，原名羅絲•馬梅拉克 (Rose Mamelak)，1936 年與家人一起抵達蒙特利爾。 最初她不會說英語，後來以班級第一名的成績從 Baron Byng 高中畢業。在女權主義母親的鼓勵下，羅斯就讀麥吉爾大學，並靠著獎學金養活自己。

她主修微生物學，但很快就轉向新興的生物化學領域。正如她在 1984 年的自傳文章《由內而外的感覺》中回憶的那樣，她意識到：“對生命系統中化學元素的研究讓我充滿了前所未有的興奮和興趣。”

科學界女性的先驅
1953 年，她獲得博士學位，同年與道格拉斯•約翰斯通 (Douglas Johnstone) 結婚。他們搬到英國兩年，以便她可以從事博士後研究。 1961年，她回到麥吉爾生物化學系擔任助理教授。 1967 年晉升為副教授，1977 年成為正教授，並撰寫了 132 篇同儕審查出版品。

約翰斯通是第一位擔任吉爾曼切尼生物化學系主任的女性，1980 年至1990 年間擔任生物化學系系主任，是麥吉爾大學第一位領導基礎科學系的女性，也是當時北美五名女性之一。

她是學術界同工同酬的倡導者，曾在麥吉爾婦女地位委員會任職，幫助挑戰性別歧視。她的兒子 Michael Johnstone（MDCM）為紀念她設立了 Rose Mamelak Johnstone 研究獎學金，以鼓勵女性追求科學事業。

外泌體的發現
透過1970 年代和1980 年代對紅血球和鐵吸收的研究，約翰斯通和她的研究團隊發現並命名了外泌體——起源於我們細胞內部的囊泡，用於在細胞之間留下並攜帶蛋白質和遺傳訊息。

她的研究表明，成熟紅血球表面不存在鐵結合蛋白。她發現了一種新的囊泡結構，並將其命名為外泌體。她發現，透過外泌體，鐵結合蛋白離開網織紅血球（未成熟的紅血球），使紅血球成熟。 （沒有鐵，紅血球就無法吸收或輸送氧氣，生命就會停止。）

約翰斯通也發現了細胞分泌外泌體的獨特途徑，將其與其他類型的囊泡區分開來。

外泌體現在因其在免疫系統、大腦和心臟細胞之間正常通訊中的作用而受到認可。它們也與神經退化性疾病、肝臟疾病、心臟衰竭和癌症有關。根據加拿大百科全書 2019 年的條目，自從她發現外泌體以來，科學家們已經發表了 8,400 多篇關於外泌體的論文。令人驚訝的是，今天，同行評審論文學術庫 PubMed 中顯示的數字為 31,415 篇。

科學協會，例如美國外泌體和微泡協會和國際細胞外囊泡協會、期刊（細胞外囊泡雜誌）、資料庫（ExoCarta、Vesiclepedia）和研究入口網站（exRNA）現在致力於該領域，約翰斯通的研究有助於建立。

如今，外泌體正在成為一種有前途的精準藥物遞送方式。載體。例如，這對於新興的 RNA 療法尤其有希望。

大自然的力量
“羅斯是一位科學家中的科學家。我很欽佩她，」加拿大分子遺傳學研究主席、2000 年至 2013 年擔任生物化學系系主任的 David Y. Thomas 說。

湯瑪斯指出，約翰斯通的工作為隨後幾十年的重要生化研究奠定了基礎。他提到了麥吉爾兒科教授兼麥吉爾大學健康中心研究所的高級科學家 Janusz Rak 目前的工作，他的研究包括外泌體和人類癌症進展中細胞內連接中斷的研究。

目前的另一個例子是麥吉爾大學校友Antonin (Tony) De Fougerolles 博士的工作，他是Evox Therapeutics 的首席執行官，Evox Therapeutics 是一家生物技術公司，專注於「提高外泌體的自然遞送能力並開發全新的治療方法」。到他們的網站。

麥基爾大學生物化學系系主任兼麥吉爾 RNA 科學中心 (MCRS) 主任 Thomas Duchaine 博士指出，該中心於 2022 年成立，「感謝 Rose Johnstone 等科學家的基礎工作，MCRS 正在利用RNA 在生物技術和多種人類疾病的治療中發揮作用。

基於好奇心的科學之路
2005年，約翰斯通撰寫了一篇論文，「重溫外泌體的發現之路」。在其中，她描述了漫長且不確定的試錯過程，正如她和她的團隊所發現的那樣，“這些小結構的蛋白質含量相對較低。”

她的閉幕詞反映了科學探索的本質：

「一種新描述的生物現象可能需要數年時間才能變得不僅僅是一種好奇，並且它的潛力得到認可。一旦被認可，興趣的增長可能會非常迅速。也許我們正處於後一階段的門口。

3 Ultracentrifugation methods for isolation/purification of exosomes
"外泌體分離/純化的3種超速離心方法"

https://www.thermofisher.com/blog/life-in-the-lab/a-deep-dive-into-ultracentrifugation-techniques/

A comparison table of Differential Ultracentrifugation (DUC), Density Gradient Ultracentrifugation (DGC), and Zonal Density Gradient Ultracentrifugation (ZONE-DUC) in terms of their variations, benefits, and specific details:

差速超速離心（DUC）、密度梯度超速離心（DGC）和區域密度梯度超速離心（ZONE-DUC）在變化、優點和具體細節方面的比較表：



https://www.thermofisher.com/blog/life-in-the-lab/a-deep-dive-into-ultracentrifugation-techniques/

An updated comparison of exosome isolation methods

Do you want to know the initial concepts of two plastic surgery mentors about endoscopic lifting in early 1995?

Summary of Ramires's Concepts and Techniques in Endoscopic Surgery
Dr. Oscar M. Ramirez emphasizes the benefits of endoscopic techniques for facial rejuvenation, particularly for younger patients who find traditional open surgeries unacceptable. He advocates combining endoscopic methods with traditional approaches for older patients to minimize undesirable outcomes and complications. Key points include:
1. Subperiosteal Dissection: Widely preferred for upper face rejuvenation due to its advantages in visualization and ease of manipulation. Ramirez extends this to midface rejuvenation.
2. Forehead Lift: Ramirez prefers using three incisions instead of five for a more straightforward approach and recommends avoiding blind dissection near the orbital rim to prevent nerve damage.
3. Fixation Methods: Utilizes percutaneous screws and skin staples for precise and adjustable fixation, particularly beneficial in cases of asymmetric brows.
4. Mandibular Dissection: Performed selectively, highlighting its utility in specific cases.
5. Neck Procedures: Extensive subplatysmal dissection with the endoscope allows for effective muscle plication in the submental area.

REFERENCE:
1. Ramirez OM. Endoscopic subperiosteal browlift and facelift. Clin Plast Surg 22(4):1995 (in press).
2. Nahai F. Editor's Perspective. Perspectives in Plastic Surgery, 1995.

An earlier article (2012) in Arabia illustrated the isolating methods for exosome giving and highlighted the revolutions currently taking place.