1

Cells, Microbes & Viruses / Can antibodies be used as a vaccine against HIV?

« on: 04/12/2011 01:11:31 »

AIDs vaccines of many types has been actively pursued for a good while with little to any success. Some attribute this to lack of fcus - moneys are spread unproductively - alot of money but heavily diluted among concepts and substantial bureaucracy.

2

Cells, Microbes & Viruses / Do biological washing powders kill bacteria?

« on: 27/11/2011 23:44:56 »

Sure bored - the risk is that contaminated laundry may act as a fomite carrying viable pathogens in numbers sufficient to cause disease from a contaminated source to a susceptible individual exposed to laundry during or after laundry process - per old story think smallpox/blankets/indians.  Risk assessment would consider pathogenicity, infectious dose, mitigation (disinfection, dilution/heat in washing), susceptibility of hosts, etc.  High risk would be for example Clostridium difficile in hospital and nursing home operations.  In modern households, risk would probably be episodic and low.   In US, products are marketed to both scenarios and in both must satisfy EPA criteria and registration.

3

Complementary Medicine / Re: Are there health benefits to drinking tea?

« on: 27/11/2011 18:33:19 »

Can folks provide some technical references?  I know there are some and not something from cooks corner claiming a "growing body" of information" and alot of rumor.

4

Cells, Microbes & Viruses / Would \

« on: 27/11/2011 17:44:23 »

Can you provide details - identities of the microbes? how the combination is supposed to work, supplier literature?

Sounds like alot of hype but I guess you could try it.

5

The Environment / Why don't tornados hit downtown urban areas?

« on: 27/11/2011 17:39:30 »

They're attracted to trailer parks and downtown areas don;t have alot of these,

6

Plant Sciences, Zoology & Evolution / Why is dark skin better for hot climates?

« on: 27/11/2011 17:37:44 »

It is not a "reason" - sensible or otherwise- no superior being reasoned and established dark pigmentation as better in climates of greater exposure to radiation.  Evolution is not reasoned process and it doesn't make "mistakes"  - it is shotgun and emperical.
It happens that dark skin is more common in some of those environments and melanin pigmentation of that darker skin does provide active and passive protection vs. radiation of all types.

7

Physiology & Medicine / How can scientists tell how much of our brain we use?

« on: 27/11/2011 17:18:55 »

Think the 10% use concept is a myth.

8

Cells, Microbes & Viruses / Is there more bacterial biomass than human in my body?

« on: 26/11/2011 12:59:19 »

Interesting question.  You're probably right - folks estmate the weight of an "average" bacterial cell is about 10E-13 g vs. about 10E-9 for an "average" human cell.  Even if we were 99% microbial in composition, these four orders of magnitude would leave us weighted as human.

9

Cells, Microbes & Viruses / Can the sun kill germs?

« on: 26/11/2011 12:52:25 »

Please try to remember the original question was offered in context of clothing.  Bugs in that context would be staph, corynebacteria, Malassezia fungi and a variety of other transient and less well studied normal flora as well as dust and soil drtived bacteria.  These are not present as isolated cells but associated with soils such as dust, dried body secretions, skin cells etc.  These associations with the very small number actually be exposed to incident sunlight and with microbial repair of UV damage - would bring very little practical reduction in viability.   
Catalase, superoxide dismutase and other specific and non specific capabilittes (bacterial spores)address some of the other (irrelevant) factors offered.  Yes, pigmentation - melanin, carotenoids etc indeed do mitigate UV and oxidant based killing but are doubtfully involved in context of flora on clothing. 

10

Cells, Microbes & Viruses / Can the sun kill germs?

« on: 23/11/2011 12:43:24 »

Like to see Bored Chemist's data.  Nizzle is correct and diminished microbial survival would be more  a function of drying and some degree of heat han "sunlight".  Light will not penetrate clothing and UV dosage even at the surface would be minimal - with photoreactivation repair mitigating it's effect.  UV treament used commercially for water and air is much more intense and focused.

11

The Environment / My Idea for a Sea based carbon sink system.

« on: 23/11/2011 12:35:51 »

You say "substantial."  Give us some hard numbers - what would be the amount of carbon sequestered?

12

Cells, Microbes & Viruses / Do biological washing powders kill bacteria?

« on: 17/11/2011 01:53:52 »

You should have learned rik assessment in your 15 years.  No sure the relvance of your claim of "sterile" (most microbiologists refer to it as aseptic) technique. 

p.s - Please pay attention. I did't recommend laundry disinfection in the home.  However, products exist for this specific application. The methodology derives from hospital applications (http://www.epa.gov/oppad001/dis_tss_docs/dis-13.htm).

13

Cells, Microbes & Viruses / How do bacteria survive a mouth wash?

« on: 17/11/2011 01:42:22 »

Good point Nizzle.  Bacteria responsible for many recalls of mouthwash are primarly water-born heterotrophs such as Burkholderia cepacia.  Not aware of data for contamination in use.

14

Cells, Microbes & Viruses / Do biological washing powders kill bacteria?

« on: 12/11/2011 04:00:46 »

I'm a microbiologist - you apparently are not.  Risk means risk - whether small or large.  I'm sure even you can think of a scenario of risk - and do spare me your amateur epidemiology.

15

Cells, Microbes & Viruses / Do biological washing powders kill bacteria?

« on: 12/11/2011 02:58:52 »

Clothes dryer heat was not part of the question - do washing powders kill bacteria.
But you are correct.  Any risk would probably come with transfer of wet clothes to the dryer.

16

Cells, Microbes & Viruses / How well do hand sanitizers work?

« on: 12/11/2011 02:54:28 »

You need to consider context that bacteria are rarely encountered, beyond the artifical construct of lab cultures, as isolated cells prone to alcohol kill. Hand santizers are qualified on the basis of their kill of freshly applied lab grown single cells cultures on hands.  Bacteria under fingernails in adjacent folds and in soils are not substantially affected.

Vegetative bacteria in biofilm are also not killed even if immersed in alcohol.
Infect Control Hosp Epidemiol. 2004 Mar;25(3):231-9.  Outbreak of Burkholderia cepacia bacteremia traced to contaminated hospital water used for dilution of an alcohol skin antiseptic.

17

Cells, Microbes & Viruses / How do bacteria survive a mouth wash?

« on: 12/11/2011 02:33:18 »

Bacteria are more frequently encounter in nature as communities of cells living in a matrix - think gel - gel of polysaccharide, and other mineral and biological materials.  The matrix with cells is the "biofilm".  Here's a link to a good description - http://www.cs.montana.edu/ross/personal/intro-biofilms-s4.htm and a recent article describing the resistance of bacteria in biofilm to disinfecants.

Biofouling 2011 Oct;27(9):1017-32.  Resistance of bacterial biofilms to disinfectants: a review.

18

Cells, Microbes & Viruses / Do biological washing powders kill bacteria?

« on: 08/11/2011 15:43:15 »

I'm familiar with data indicating primary bacteria found in in the washing process are enterics.  Do you have data re. skin flora being primary?
 

19

Cells, Microbes & Viruses / Do biological washing powders kill bacteria?

« on: 06/11/2011 23:40:41 »

Perhaps you might acquaint yourself with real life microbiology/microbiological soils. In that context, you need to apply mechanical disruption of biofilm with bleach to get it "clean" presuming you've not scale.  But be my guest, you and Hoffman can add bleach and watch the biofilm not disappear.

 

20

Cells, Microbes & Viruses / How do bacteria survive a mouth wash?

« on: 05/11/2011 22:13:47 »

It was!!!!  A hospital trying to work in Beirut's turmoil and abyssmal water quality.