2016年11月27日 星期日

同性戀和愛滋病有關係嗎?

前幾天某反同婚的朋友拿出一個衛福部的報告說,同性戀得 AIDS 的比例比較高,而我記得之前有個 seminar 的講者也有講到(雖然我忘了那次演講的題目是什麼),不過以病毒學的角度來看,這不合理啊,因為病毒傳染是 species-specific,不是 sex-specific,如果是一樣的傳染途徑,應該是不管性別,所有的性行為都是一樣的機率,於是剛剛就孤狗了一下看有沒有全球性的報告,而不是只有台灣的。全球的當然就是先到 WHO 官網上去找找看,結果發現因為 AIDS 的最大人口都是在非洲,所以主要以非洲為主,不過大家以為的 MSM (men who have sex with men) 為主要傳染途徑其實是因地而異的 [1],在非洲或東南亞國家,愛滋是因 MSM 傳染的比例比較少 [2],主要是以多重性伴侶和 drug injection 為主,而在西方國家或高收入國家,才是以 MSM 為主要傳染途徑。



為什麼會有這種區別呢?以目前的資料看來,是因為非洲和東南亞的性行為的安全措施觀念還不普遍,所以在各種傳染途徑都是相同競爭的情況下,多重性伴侶(也就是 heterosexual 為主)的愛滋人口還是最多的,在高收入高開發國家,因為性行為的安全措施觀念已經普及,所以這條傳染途徑被大大降低了,但是為什麼 MSM 得愛滋的比例還是比較高呢?Cold Spring Harbour 的研究報告中說 [2]:

"Both behavior and biology are relevant to the MSM epidemic. Multiple sexual partners, use of recreational drugs and alcohol proximate to sex, and the practice of unprotected anal intercourse all increase HIV risk markedly. Rectal exposure to HIV is more likely to infect than vaginal exposure (Powers et al. 2008; Boily et al. 2009; Baggaley et al. 2010). This is likely owing to the large surface area and thin epithelial layer of the rectum, its capacity for fluid absorption, trauma during anal sex, and the high numbers of immunological target cells in the gastrointestinal tract (Dandekar 2007; Brenchley and Douek 2008)."

這也是為什麼 AIDS 在高開發國家的傳染途徑,即便是在同性戀之間,也還是以男性為主,而不在於女性之間。總結來說,愛滋的傳染在性行為上,跟是否 heterosexual 還是 homosexual 沒太大關係,主要是因為沒有安全措施的性行為,如果 MSM 的保護措施普遍化的話,應該是可以降到和 heterosexual 差不多,根據 Cold Spring Harbor 的資料:

"Despite the worrisome trends among MSM as a whole, the proportion of all reported HIV/AIDS cases that have occurred among White MSM in the United States has dropped markedly from the 80% range in the early 1980s to 25% in 2010."

所以其實拿同性戀的愛滋比例高來反對是沒有道理的,因為重點不在是同性還是異性,而是在於性行為是否有做安全措施。(如果大家這麼怕得到愛滋,可以萬人連署,請總統下令全面禁止性行為。)

"It is thought that the more pragmatic sexual education approaches in Europe and Australia, with structural changes like widespread provision of condom dispensing machines in bathrooms, may explain why the heterosexual epidemic among heterosexuals has been lower than in the United States where comprehensive sex education and condom advertising and distribution have been comparatively curtailed (Dworkin and Ehrhardt 2007)."



參考資料:

1. WHO UNAIDS Global AIDS Update 2016

2. WHO: Understanding the modes of transmission model of new HIV infection and its use in prevention planning

3. SH Vermund and AJ Leigh-Brown, The HIV Epidemic: High-Income Countries. Cold Spring Harb Perspect Med (2012)










2016年11月18日 星期五

學術倫理案件:PubPeer vs. WSU 教授論文造假 (updated)

台大醫學院造假的新聞出來後,今天剛好看見這一篇新聞,其實也不算新,事情發生在兩年前,只是這兩天有新進展。是說兩年前有人用暱名在 PubPeer 質疑兩篇 WSU (Wayne State University) Dr. Sarkar 實驗室的論文有造假的嫌疑,結果之後這兩篇被刪掉了,匿名者於是問 PubPeer 的管理者為什麼刪他的文,管理者回說因為收到 legal threat,覺得再這樣下去要是對方提告,法院可能要求 PubPeer 公開匿名者身份,所以便把匿名者的那兩篇文章刪了。

August 2014: PubPeer Threatened with Legal Action

事情發生的隔天,The Scientist 報導了這件事,當時這篇新聞並沒有寫發出 legal threat 的人是誰。

October 2014: Pathologist Sues PubPeer Users

但是一個月後,則由 Dr. Sarkar 的律師 Nicholas Roumel 公開向 PubPeer 提告,說這件事害 Dr. Sarkar 失去了工作,密西西比大學撤銷了原本要給他的終身教職(tenured professorship),這包括了 75 萬的 start-up package,35 萬的年薪和一萬五千塊的搬家費,另外提供一間實驗室、一間辦公室,兩個 RA 和一位行政等等。Sarkar 原本八月要開始在密西西比大學的新工作,於是在五月就辭了在 WSU 的教職,也準備好搬家了,但是在六月的時候收到密西西比大學的信說要終止給他的 offer,原因是收到來自 PubPeer.com 的轉寄匿名信,內含有關於他實驗室發表的論文的 posts。

March 2015: Judge Wants Info on PubPeer Commenter

這件事上了密西根法庭,法官要 PubPeer 提供匿名者的資料。

Oct 5, 2016: Michigan State Court of Appeals Hears Arguments in PubPeer Litigation

Dr. Sarkar 的律師要求 PubPeer 提供匿名者資料,認為他詆毀 Dr. Sarkar 的名譽,害他失去教職,但是 PubPeer 拒絕,認為這個案件關係重大,因為這代表是否以後可以匿名討論科學文獻。PubPeer 的律師 Alex Abdo 表示如果這場官司沒贏的話,他們將上訴到最高法院。

“When you’re talking about facts that are in the public domain, you’re stating your opinion,” he said. “And the First Amendment has always protected that right. Sometimes people disagree with the opinions of others, but we live in a free society. We don’t live in one in which the courts can be used to patrol the terms of scientific debate.”

Abdo 說 WSU 也開啟內部調查,確認 Dr. Sarkar 是否有造假 data。而匿名者 Clare Francis 也告訴 The Scientist [註],如果他最後還是被要求公開身份,他就會直接指責 Dr. Sarkar 是個 fraudster,證據是他有 18 篇論文被撤。

At stake is the protection of anonymous post-publication peer review. “It’s extremely important that scientists feel as comfortable as possible participating in this conversation and giving their assessment of published research so that we can change the way that science is communicated,” Stell told The Scientist.

Oct 19, 2016: Investigation Finds Pathologist Guilty of Systemic Misconduct

WSU 內部調查發現 Dr. Sarkar 實驗室的確有 fabrication, falsification, and/or plagiarism of data 的情形 -- 在 Dr. Sarkar 的默許下,而他也用這些 data 申請到不少 funding,不過 Dr. Sarkar 否認了全部,說他發表的論文並沒有 falsification 的情形。

"Most of the allegations involved the reuse and relabeling of images in figures that were published in scientific journals, used to support grant applications, employed to communicate progress on funded projects, or printed in a patent application and dissertation. The images involved western blots, electrophoretic mobility shift assay (EMSA) data, cell culture photographs, and other research outputs."

調查委員會說,Dr. Sarkar 不能以因為太忙,所以沒注意或不知道實驗室發生什麼事來推卸責任,他既然是指導教授,就要負責實驗室正常運作,嚴格檢視和確認實驗資料和數據。

“The Investigation Committee concludes that Dr. Sarkar has no basis to claim that he did not know what was happening in his laboratory because he was too busy or not paying attention,” the report stated, referring to Sarkar’s responses to questions from the panel. “The evidence shows that Dr. Sarkar failed to establish or maintain standards of quality control in record keeping, or to exercise due diligence to correct unacceptable practices. The Committee concludes, based on an examination of the evidence, that Dr. Sarkar’s failures of mentorship and laboratory management rise to levels of recklessness that enable irresponsibility, uncritical collegiality, acceptance of poor laboratory practices indiscriminant [sic] awarding of authorships, and ultimately resulted in widespread research misconduct by him and others.”

Oct 19, 2016: Misconduct Finding Could Impact PubPeer Litigation

Oct 20, 2016: PubPeer Requests that Court Consider Misconduct Investigation

註:Clare Francis 是網路匿名代號,起源請見:What to Do About “Clare Francis”


我是覺得既然都公開發表論文了,就要對自己發表的東西負責啊,理當讓大家檢視,是不是毀謗或無誣指偽造跟匿不匿名沒太大關係,科學本來就是讓人公開討論的,數據和圖片都公開在網路上,是不是偽造或是不是毀謗大家點進去看就知道了,如果最後法院判決要提供匿名者資料,這是說科學不能接收受公開討論嗎?

btw, 原來美國教授薪水年薪 35 萬啊阿阿~~
然後我覺得匿名者應該原本就是內部知情人士,只是看不慣很久了又不知道要到哪裡舉發,就直接在 PubPeer 舉發了。


12.07 update:

PubPeer wins closely watched legal battle over anonymous comments. Science Magazine (2016)