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What happens when the coronavirus enters your body? Why we react so differently

Larry Segura

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What happens when the coronavirus enters your body? Why we react so differently

The immune system protects us, but in the most serious cases of coronavirus it seems to be overreacting and counterproductive, as it happens in other diseases

From the cases that go unnoticed because they do not give symptoms until death: the range of reactions caused by SARS-CoV-2 is wide and perplexing. Why does the same infection have such disparate effects? If statistics tell us anything, it is that age has a lot to do with it. In the first decades of life, there are hardly any complications, although some specific cases are difficult to explain. On the other hand, as the years of the patient’s increase, hospital admissions, cases in the ICU and deaths multiply.

Can everything be explained by the existence of previous pathologies? Hypertension, diabetes and cardiovascular diseases have been identified as risk factors, but there is a more basic question: what does the immune system do when attacked by an external enemy. In the face of an unknown virus, an innate response occurs, and, later, when our defenses already recognize the pathogen, the adaptive response arrives, which acts specifically against that threat. However, something seems to be failing in the most serious patients of this new coronavirus in this second phase: an exaggerated response that ends up causing damage to the body and does not prevent the virus from multiplying.

“It is striking that there is a lot of heterogeneity in the clinic of this virus, and this may be related to a wide variety of immune responses, some are more effective and neutralize the virus, and others lead to the disease, ” José Manuel told Teknautas Bautista, a molecular biologist from the Complutense University of Madrid, “but we really still know very little, each virus can behave differently even if there are common characteristics among those of the same family.”

“Viruses behave differently in each individual and challenge their immune system, ” explains virologist Raúl Ortiz de Lejarazu, former director of the National Flu Center in Valladolid. “What happens in each body has to do with individual factors that we do not know well, we know in the flu and in other diseases already studied, but not in this coronavirus,” he admits.

As an example of the heterogeneity in the response to viruses, this expert gives an example he knows well: “ In the 2009 influenza A pandemic, it was soon seen that the obese reacted worse, among this group there were many more people who fell ill with seriously because they had a different inflammatory profile than people with normal weight. ”

How the immune system reacts

At the beginning of an infection, the innate response occurs — it is called that because it is common to all people against a pathogenic microorganism, even if we have not been exposed before. This works “by a very primary system: I know you or I don’t know you, you are strange or you are not .” If we do not recognize it, a series of mechanisms are set in motion, for example, we secrete proteins called interferons and cytokines. “If this occurs normally, the result is a good physiological response that tends to heal the individual,” explains the expert.

The next step is the adaptive response. “It is a response adapted to the new pathogen as if the tailor had already taken the measurements and made the right suit against the aggression, ” he says. That is why, in almost any infection, antibodies (substances to combat it) are generated from day 12 or 13, which makes the primary and innate response more effective.

However, severe cases of coronavirus appear to be related to an exaggerated response by the immune system, which experts call a “cytokine storm.” This term was coined around 15 years ago when serious cases of avian influenza in Asia were being investigated. People who reacted badly and died had secreted many inflammatory cytokines, that is, a type of protein that generates inflammatory phenomena indiscriminately in the lung and other organs. Instead of collaborating with each other, they “ generated friendly fire damage ”.

Ortiz de Lejarazu’s research group observed that the same was true in severe cases of influenza A, according to articles they published in 2011 and 2012. That cytokine storm also happens again in severe Covid-19 cases. “ Our immune system, in the effort to eliminate the virus, damages cells and organs. The end result is that it does not control the virus, which continues to multiply, “he says.

In very different diseases, it also occurs. Bautista knows the case of cerebral malaria thoroughly. “There are many people who become infected in Africa, but only a specific population group dies, children who react aggressively with their immune response. All this is very similar to what is being described ”, he points out.

Does exposure influence gravity?

Other external factors do not influence the fact that a patient reaches this serious situation, such as having been in greater contact with the disease, as happens to health professionals, according to Ortiz de Lejarazu, who warns about the confusion that is generating the viral load concept. “It is only a parameter used in medicine as if we were talking about fever. What the viral load tells us is whether a virus is multiplying too much or too little in an organism. For example, in HIV, the viral load is used to know if the person who is infected is responding well to treatments or if, on the contrary, the amount of virus in their body increases. ”

When one acquires the infecting dose, one becomes infected. If you buy three doses, 10 or 20, you get the same infection but you will not be more serious

However, in this crisis, this concept is being misrepresented, and some are implying that the virus can accumulate through continued exposure. “The toilets do not go with a backpack carrying viruses,” he clarifies, “a person becomes infected because they acquire an infectious dose, that is, a certain amount of microorganism.” Scientists calculate what viral load is needed for contagion in mouse experiments.

“When you get the infectious dose, you become infected. If you get three infectious doses, 10 or 20, you get the same infection, and that does not have any significance on what will happen next, because in reality on the second or third day of being infected, a person produces millions of infective doses. In the body, we amplify the infective dose a lot of times and there we do talk about the viral load. The only consequence of viral load is that a person who is producing more viruses has a greater ability to transmit them, “he adds.

On the other hand, José Manuel Bautista does not rule out that prolonged exposure to the virus could have something to do with severe cases. “If only a few units of the virus infect you, they could reach a few cells and perhaps the immune response would be activated progressively so that it could contain itself better,” he says. However, “this is only a hypothesis because no experiment has been done to prove it, to see if this is the case, it would be necessary to subject mice to different viral loads and that, as they increase, there comes a time when the answer immune was not efficient. ”

The coronavirus viral load appears to peak in the first week of illness, and in mild cases, it would clear rapidly. However, seriously ill patients tend to have a high viral load and a longer period of virus shedding, according to an article published in ‘The Lancet ‘. Therefore, the viral load could be a marker to assess severity and prognosis (although this is not related to the possibility that viral load is related to prolonged exposure).

In any case, in the absence of experiments that can confirm or deny this idea, the researcher at the Complutense University considers that the reason why health professionals get sick is more likely due to other factors, such as stress decreases their immune response.

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Membrane filters you need to know and their properties

Bryan Nesbit

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Membrane filters or commonly known as “membranes” are microporous membranes with specific pore size ratings. It is also called a sieve, microporous filter, or screen. Cellulose acetate membrane filter preserves or filter particles bigger than the pore size. If there are particles slighter than the pore size, other mechanisms will be used. There are different types of membrane filters, such as nylon, cellulose acetate, mixed cellulose ester, or MCE membrane filters. Here are more membrane filter types and their attributes.

The mixed cellulose ester

MCE is composed of cellulose acetate and nitrocellulose. It has a high porosity and can provide a higher flow rate. It also has a high level of protein binding, which can be prohibited by pretreatment or application. MCE is a standard membrane that can be used in many laboratory applications, such as filtration and sterilization of biological fluids, pollution analysis, microbiology, and air monitoring. The membrane is able to be converted into transparent to view the particles collected during the filtration process.

Cellulose acetate-

coated cellulose acetate consists of cellulose acetate cast on a non-woven polyester carrier. It has a non-fiber releasing ability, and the protein binding level associated with nitrocellulose is low. It also has a low level of static charge and chemically enhances compatibility with low molecular weight alcohols. The coated cellulose acetate is used as a pre-filter or clarification filter.

Hydrophilic PTFE

Hydrophilic PTFE has characteristics described as having the greatest resistance to chemicals and pH. The membrane has a high level of flow rate and almost no water-extractable. When the membrane is wetted with water, it is transparent to the naked eye, so it is very suitable for use in HPLC, organic solvents, and other aqueous mixtures.

Hydrophobic

PTFE The characteristic of hydrophobic PTFE is that it has a high porosity is very thin and behaves like a monolithic retention membrane. It also has a passive effect on most corrosive chemical solvents, alkalis, and strong acids. The membrane traps water-containing aerosols by sterilizing the gas. It is also used for gas and air discharge so that gas can freely pass through the membrane, and at the same time prohibit liquid from entering. This protects the best samples and vacuum pumps. In addition, hydrophobic PTFE clarifies and sterilizes strong acids and other solvents that are incompatible with other membrane filters.

Nylon

nylon membrane filters are made by impregnating polyester fiber webs with polymers made of nylon. This makes the membrane durable, heat-resistant, and essentially hydrophilic. Because it is hydrophilic, it is suitable for alcohol and aqueous samples. The membrane filter can be used to sterilize, filter, and clarify organic aqueous solutions.

Cellulose acetate

The membrane filter is composed of diacetate and cellulose triacetate. It is characterized by high strength and low electrostatic charge. The advantage of using it is that it can be repeatedly disinfected without losing its integrity or changing its bubble point. Associated with MCE membrane filters in stipulations of their solvent confrontation to alcohol molecular weight increase at low levels.  Cellulose acetate is used to enhance the recovery of positive organisms and filter enzyme solutions. It is also used for cytological diagnosis and receptor binding research.

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Rapid production of porous cellulose acetate membrane for water filtration using readily available chemicals

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Abstract

We describe a chemistry lab experiment using everyday elements and readily available chemicals to introduce porous polymer membranes to high school and college students. The principle of membrane filtration is illustrated by filtering solutions containing watercolor pigments or food coloring, while the food coloring is completely soluble in water and easily passes through the membrane. . The laboratory experiment can be performed in a 2 hour activity and is intended to (1) expose students to an exciting new field of materials science. He familiarizes them with porous membranes for the production of drinking water and presents them with a model elimination technique that uses the acid / base theory. In Switzerland, 52 high school students and 55 high school teachers have already successfully completed the laboratory experience and found the activity interesting and motivating.

 

introduction

Importance of safe drinking water

Access to clean and safe drinking water remains a global problem. In developing countries, around 80% of diseases are linked to poor water and sanitation conditions. Among the most common health risks of unclean drinking water are water-borne illnesses caused by pathogenic bacteria, viruses, and protozoan parasites. In a comprehensive study, Bain and colleagues examined the microbial quality of drinking water and estimated that approximately 1.8 billion people worldwide use a source of drinking water contaminated with E. coli or other bacteria. thermotolerant coliforms (TTC).

Various approaches, with their inherent advantages and disadvantages, have been studied for eliminating microorganisms linked to waterborne diseases. The portable water purification devices currently in use include systems based on ultra and microfiltration membranes, ceramic filters, activated carbon filters or chemical halogen disinfection. The disadvantages of the most efficient systems are, in general, their complex installation and their periodic maintenance, which leads to high operating costs and, consequently, makes these systems unsuitable for developing countries. In addition, many point-of-use treatment devices are not effective against all possible contaminants. Therefore, new water treatment technologies are being explored.

Water quality issues are an integral part of many high school chemistry courses, and various experiments have been developed as educational laboratory procedures. Water filtration experiments for the removal of nanomaterials have already been described and a laboratory experiment comparing various biochemical separation technologies (including filtration) has been presented. The experience presented here differs from previous approaches in that the filtering device itself (a porous membrane) is made by students from standard materials, then its separation performance is tested.

Cellulose Acetate Membrane for Water Filtration

In this article, we describe a laboratory experiment to produce a cellulose acetate membrane filter for drinking water which, in its production stages, resembles the commercially available water filter, but which is accomplished using everyday items such as a kitchen blender, glass dishes, rulers and chemicals readily available. The entire experiment can be performed in a 2 hour laboratory exercise. Supporting information for this article includes a student brochure and instructor notes for conducting the classroom experience (approximately 20 to 40 students). The production of membranes is based on the addition of calcium carbonate to a solution of cellulose acetate dissolved in acetone. Glycerol is also added to the reaction mixture and acts as a pore spacer. The polymer solution is then mixed using a kitchen mixer, and the resulting dispersion is spread on a glass plate using a stainless steel ruler. After evaporation of the solvent in ambient air, the calcium carbonate and glycerol particles are washed from the polymer matrix in an acid bath and then rinsed in a water bath.

Functional test of the membrane using watercolor and food coloring

Students test the performance of the membrane obtained with a solution of watercolor and food coloring. Although, when mixed with water, both give colored water, the color of the food used is a water-soluble dye, and watercolor is a dispersion of pigments, with particles between 40 and 80 µm in size. The watercolor solution based on pigments is first passed through the membrane. Then the filtration is repeated with the food coloring solution. In both cases, students are invited to record their observations. The experiments with the two solutions are then repeated with a standard filter for a Buchner funnel.

Procedure

Equipment and chemicals

The experiment uses the infrastructure and materials available in a university-level chemistry laboratory (see Information on teaching support and notes to students), as well as certain additions, which can be easily obtained:

• Kitchen mixer with at least 800 W of power (eg Philips HR 2195/04)

• Mirror or glass plate (148 × 210 mm2 or larger area)

•           Tape

• Ruler with stainless steel edge or aluminum profile.

• Two plastic tanks for dilute hydrochloric acid and a double boiler.

• Cellulose acetate (Sigma-Aldrich n ° 180955)

• Calcium carbonate (Sigma-Aldrich No. 21069)

• Watercolor (for example, Artists Loft Fundamentals watercolor pans set on amazon.com)

• Food coloring (for example bright blue FCF E133)

Preparation of a solution of cellulose acetate polymer

Preparation of the cellulose acetate dispersion

All of the cellulose acetate membrane filter was transferred to a kitchen mixer. Then, 41 g of calcium carbonate and 17.6 g of glycerol were added, and the suspension was stirred for 3 minutes in the highest setting of the kitchen mixer. The dispersion was placed in a new 250 ml Schott bottle and closed to limit evaporation of the solvent. The kitchen mixer was immediately filled with water to precipitate the remaining dispersion and the polymer waste was deposited in household waste.

Removal of calcium carbonate particles

To remove the calcium carbonate particles, a plastic container was filled with 5 L of water and another container with 5 L of hydrochloric acid (0.24 M). The mirror plate containing the membrane sheet was then immersed in the hydrochloric acid bath. The membrane sheet was released from the mirror plate, and gas bubbles indicated the removal of the calcium carbonate particles. After 10 minutes, the membrane sheet was transferred to the container containing only water and washed for an additional 5 minutes. Finally, the membrane sheet was removed from the water bath and placed on a cloth. Another kitchen towel was used to dry the membrane.

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Orlando Dermatologist Reports Coronavirus Rash- Sunlight Needed for Vitamin D

Chris Rynolds

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Getting to deal with a whole new disease is very unsettling. No one has answers to anything, and that is enough to cause panic across any nation.

Well, that is precisely what is happening now with the Coronavirus. All the symptoms cropping up from different areas is bringing in more worry and doubt. The Coronavirus is an upper respiratory disease that gets in the way of your breathing, and it makes it harder for air passage in and out of the lungs. And now, there is something else worrisome — the Coronavirus rash.

So what is this rash, and where has it come from?

Is there any relation between skin rashes and Coronavirus

Doctor around the world including any Orlando dermatologist attest that it is not unusual to see skin rashes on someone infected with a viral infection. Just like herpes that appears around the lips and chickenpox that present all over the body.

The reasons this can happen is one, the rashes are a by-product of a robust immune system fighting against the virus. And two, it could be that the virus is directly affecting the skin cells as in the case of the chickenpox. Studies on the sources and targets of the coronavirus rash are still unknown.

The rashes have manifested in several ways so far. These are:

  • Head to toe rashes
  • Hive-like eruptions
  • Blisters
  • Purple rashes across the body
  • Bumps and lesions on the heels and toes

Now, what is perplexing is that these rashes are presenting on younger coronavirus patients. But any Orlando dermatologist should not make any conclusions yet as it is known that sometimes viral infections can impact almost every organ in the body, including the skin. The astonishing part is that the rashes are presenting differently from one patient to the other.

Types of rashes reported

Livedo Reticularis

The first kind of rash is the Livedo reticularis which is a vascular condition. It is characterized by mottled, purplish discolourations that mostly appear in the legs and appear to form a net-like pattern.

Petechial

This rash appears like a bright red, pinpoint rash that is commonly seen in other ailments. It is caused by bleeding under the skin.

Vesicular

A vesicular rash is diagnosed when a rash appears in the same spot as multiple vesicles with fluid trapped under the top layer of skin. The blisters are painful to touch, which make it hard to resist touching because they are itchy.

Acral Ischemia

This is a chicken-pox-like rash that appears specifically on the toes. It seems to be raised, looks like frostbite because of the purple lesions. These rashes are what has been named the COVID toes.

Morbilliform

These rashes look like measles rashes. They consist of maculopapular skin eruptions and are mostly because of hypersensitivity in patients taking antiretroviral and antiepileptic drugs. It is also a common outcome in viral infections like Coronavirus.

Urticaria

These are commonly known as hives or nettle rash. They are an outbreak of red bumps that are mostly triggered by several things, include medication reactions, allergies and infections.

Is there a cure for these rashes?

Any Orlando dermatologist would love to say that there is, but there is no known cure for the rashes. What doctors are doing is keeping the lesions in control using anti-inflammatory medications. And the fact that they are presenting in different forms makes it more challenging to come up with one specific cure.

With that said, it is still advisable for anyone showing any of the above symptoms to seek medical assistance immediately. Not all rashes are a result of Coronavirus, so it is safe to see a doctor first. So eat right and know that sunlight needed for vitamin D, especially in people of colour is essential too.

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