Resources
April 18th, 2021 by Dr. Hannah Sivak
I don’t know of any papers that address this issue in skincare. But we know that microbes can adapt to the environment and even mutate, giving us bacteria that become resistant to antibiotics. I also know that even if products stay the same, the skin doesn’t. You may think that your kin has become “resistant” to an ingredient used to decrease sebum secretion, while what actually happened is that your skin has changed in response to the hormonal cycle. A product may have been bad for you from the start, and your skin may be responding to a constant change in acidity. Frequent peels will decrease the efficacy of the…
April 18th, 2021 by Dr. Hannah Sivak
We ignore the menstrual cycle at our own peril because it matters. Acne is common in postadolescent women, and an increase in lesions may be noted in the last 7-10 days of the menstrual cycle. Why? Changing hormones across the menstrual cycle produces measurable variations in immune function and susceptibility to disease. The skin and scalp have estrogen and progesterone receptors in both the dermis and epidermis. Levels of estrogen and progesterone fluctuate during the cycle and influence numerous characteristics of the epidermis, including lipid secretion and sebum production, skin thickness, fat deposition, skin hydration, and barrier function. Dermal collagen content, which contributes to skin elasticity is also affected. Estrogen…
August 19th, 2020 by Dr. Hannah Sivak
1. You are writing a detective book. 2. You wish to poison an enemy (Lieutenant Columbo will get you!) 3. You want to kill cancer cells (and the cancer patient) 4. To kill a virus, but you are likely to be killed before the virus is 5. You believe the mypillow guy and all the crackpots out there (but not the scientists and the MDs!)
August 3rd, 2020 by Dr. Hannah Sivak
Whether you are 13 or 31 you still have to think long-term: your skin will be the barrier to protect you from the environment for the rest of your life (which I hope it will be long and happy). Because you have to think long term, you have to be careful when you buy an anti-acne product. Why? Because many companies don’t think long term about your skin when they formulate their products. Many companies only think of making money fast and their interests are unlikely to fit with yours. What should be your objective? To control acne without damaging your skin or aging it prematurely. And yet, many ingredients…
July 16th, 2020 by Dr. Hannah Sivak
What’s special about eyebrows? They grow slowly. Not so special: they can die. Teenagers eager for some sort of control on their bodies often go for eyebrows, not knowing (or caring) that they can lose them, actually losing all control! On top of innocent-looking tweezers, now there is also lasers, offered by medical looking facilities that will make you sign documents with really small text where you promise not to sue them if …(here a long list of complications). Fashions come and go, but if you keep plucking your eyebrows you will not get them back. Just like the scalp can stop making hairs, so your skin can stop making…
July 12th, 2020 by Dr. Hannah Sivak
That suntan that used to be fashionable (and still is in some circles) is a signal that the UV in the sunlight has damaged your DNA. Nothing to celebrate, right? Ultraviolet light is classified into three categories: UVA (315 to 400 nm), which causes tanning, UVB (medium wave, 280 to 315 nm), which causes sunburn, and UVC (short wave, germicidal, 100 to 280 nm), which is filtered out by the atmosphere and does not reach us. Incidentally, the ozone (O3) layer of the atmosphere absorbs 97–99% of the UV in the range 200 nm to 315 nm, which is why the destruction of the ozone layer by some chemicals is…
July 5th, 2020 by Dr. Hannah Sivak
Filaggrin (filament aggregating protein) plays an essential role in the organization of keratin filaments and the development of the cornified layer (stratum cornueum) of the skin, which is an essential part of the skin barrier to epidermal water loss and to the entry of microbes and noxious substances. (There are some strange aspects to filaggrin, which point to influence beyond the skin. For example, filaggrin mutations are associated with asthma.) Figure: skin layers Dermatitis, a.k.a. eczema is the almost normal state of the skin in which the skin feels tight, itchy, even painful at times. You will see swelling, and the lesions may eventually lead to scarring. Is filaggrin involved…
June 27th, 2020 by Dr. Hannah Sivak
As we age, crucial DNA mutations accumulate in our cells, and the mechanisms that regulate cell division fail. Out of control cell division plays havoc with our bodies: it’s called cancer. As the general population ages, the incidence of cancer increases. Science had progressed enormously in the understanding and treatment of cancer, and some amazingly sophisticated therapies do exist forme some specific types of cancer. For many other types of cancer, a big part of the treatment involves removing and killing cancerous cells. Thus, surgery to remove cancerous tumors is often followed by radiation therapy. In addition to dealing with sutures still healing, the patients (us) have to contend with…
June 15th, 2020 by Dr. Hannah Sivak
Published scientific research, like any piece of writing, is a peculiar literary genre. By Carl Zimmer June 1, 2020 A lot of people are reading scientific papers for the first time these days, hoping to make sense of the coronavirus pandemic. If you’re one of them, be advised the scientific paper is a peculiar literary genre that can take some getting used to. And also bear in mind that these are not typical times for scientific publishing. It is hard to think of another moment in history when so many scientists turned their attention to one subject with such speed. In mid-January, scientific papers began trickling out with the first…
June 14th, 2020 by Dr. Hannah Sivak
Let America Be America AgainLangston Hughes – 1902-1967 Let America be America again.Let it be the dream it used to be.Let it be the pioneer on the plainSeeking a home where he himself is free. (America never was America to me.) Let America be the dream the dreamers dreamed—Let it be that great strong land of loveWhere never kings connive nor tyrants schemeThat any man be crushed by one above. (It never was America to me.) O, let my land be a land where LibertyIs crowned with no false patriotic wreath,But opportunity is real, and life is free,Equality is in the air we breathe. (There’s never been equality for me,Nor…
June 13th, 2020 by Dr. Hannah Sivak
When you look at statistics, please remember that they are built on people like you and me. If the number of hospitalized Covid 19 patients is increasing in the intensive care units of your State’s hospitals, it is because people like you and I caught the virus. The virus is still here and it came to stay until it goes away, which may be in a few years or never. Please be careful and weigh the importance of the activity you are going to do today against the certainty that the virus is around. Wear a mask and try to maintain social distance. By now, we do know that facial…
June 12th, 2020 by Dr. Hannah Sivak
We Still Go Back and Read Darwin’ Scientist David Baltimore, 82 It’s like a bad dream come true. I started off as a virologist, have read a lot about the influenza epidemic of 1918–19, and I’ve always felt a wonderment that it doesn’t happen more frequently. There are so many viruses out there in the world. Between my junior and senior years of high school, I did a visit at a mouse-research laboratory in Bar Harbor, Maine. It was on a whim, a suggestion of my mother’s. What I discovered over that summer was that the forefronts of research were available to me. I could work on a problem that…
May 19th, 2020 by Dr. Hannah Sivak
The basics of skin pigmentation are the same for different skin colors. Here they are. My skin color is different from my daughter’s. In fact, all skin colors are different, because there are infinite combinations of amounts and types of pigments present in human skin. The color of our skin is partly due to the pigment called melanin. Other factors are the content of diet carotenoids, the bluish-white color of connective tissue, and the abundance of blood vessels in the dermis and the color of blood flowing in them (oxy- and deoxy-hemoglobin). Other minor pigments (minor unless you have a bruise) are bilirubin (the yellow hemoglobin degradation product that colors…
May 10th, 2020 by Dr. Hannah Sivak
An infectious outbreak can conclude in more ways than one, historians say. But for whom does it end, and who gets to decide? Picture. A Sicilian fresco from 1445. In the previous century, the Black Death killed at least a third of Europe’s population.Credit…Werner Forman/Universal Images Group/Getty Images By Gina Kolata When will the Covid-19 pandemic end? And how?According to historians, pandemics typically have two types of endings: the medical, which occurs when the incidence and death rates plummet, and the social, when the epidemic of fear about the disease wanes.“When people ask, ‘When will this end?,’ they are asking about the social ending,” said Dr. Jeremy Greene, a historian…
May 9th, 2020 by Dr. Hannah Sivak
I can tell you, what my mother (gone a while ago) would tell me. She would tell me to take care of myself, keep my hair tidy, that I look very different from what I used to look but still beautiful. She would congratulate me for my children and grandchildren and what a great job I am doing at work and home. When our mothers are no longer with us, it is good to “keep them around”. I do it in a number of ways: cook the old recipes, listen to the old music, photos, talk (on Skype) with my cousins (my brothers are also gone). I also, always, keep…
April 24th, 2020 by Dr. Hannah Sivak
Pulse oximetry is used to measure the oxygenation level of the blood. It is an easy, non-invasive and painless measure of how well oxygen is moved from your lungs to parts of your body furthest from your heart, like arms and legs. A clip-like device, the probe, is placed on a finger or ear lobe. Nowadays, the modest (about $60, used to be $20 before the pandemic) pulse oximeter is becoming a star. For a healthy person, the probe should read 95 or higher. Surprisingly, people who are sick with Covid-19 seem to have very low readings while seemingly doing still OK. What is going on? To understand you have…
April 22nd, 2020 by Dr. Hannah Sivak
Note: this is an old post that I thought would be useful on Earth Day. You are not having déjà vu! The recipe for success: read the ingredient list of whatever you are planning to use. The problem is that sometimes the manufacturers “forget” to list an ingredient or two and then you need to read between the lines. First, let me tell you that herbicides are based on the same principle as antibiotics: they have to be selective, i.e. kill the baddie without harming the goodie, For antibiotics (and antifungals) the baddie is the microbe, and we humans are the goodies. For herbicides, the goodie is your pretty garden…
April 19th, 2020 by Dr. Hannah Sivak
These days you can’t believe everything you read. Or maybe you never could. With the internet as a medium we are bombarded with messages telling us that whatever we are doing is wrong (and to buy that other product). Stop. The person (or bot, for robot) who is telling you that is only after your “click”. There is no real information behind the panicky message. Whatever the reason for the message, the result is a flood of misinformation. The target today is sunscreen, yesterday it was antiperspirant or petrolatum or preservatives or, worst of the worse, vaccines. Don’t trust them. But you can trust me. I read the scientific literature…
April 18th, 2020 by Dr. Hannah Sivak
Your roots may be showing but you can’t get to the hair dresser? Now it’s the time to fix that area that is looking a bit forlorn. A couple of weeks is all you need to get hair regrowth and strengthening. There are so many reasons why we can lose hair at one time or another. It may be just a small area or a more generalized problem but it is usually reversible. Illness, stress or menopause are the most common causes. Chemotherapy will usually result in hair loss. What to do? Use this time when you have to stay at home to apply hair serum with keratinocyte growth factor…
April 10th, 2020 by Dr. Hannah Sivak
Ignacio López-Goñi Regardless of whether we classify the new coronavirus as a pandemic, it is a serious issue. In less than two months, it has spread over several continents. Pandemic means sustained and continuous transmission of the disease, simultaneously in more than three different geographical regions. Pandemic does not refer to the lethality of a virus but to its transmissibility and geographical extension. What we certainly have is a pandemic of fear. The entire planet’s media is gripped by coronavirus. It is right that there is deep concern and mass planning for worst-case scenarios. And, of course, the repercussions move from the global health sphere into business and politics. But…