Stem Cells, HIV/AIDS Facts, and Environmental Ecology

Stem Cells: Types and Functions

Stem cells possess the unique ability to multiply indefinitely and generate specialized cells.

• Pluripotent cells: Capable of producing most tissues in an organism, though they cannot form an embryo.
• Totipotent cells: Can transform into any type of tissue. A totipotent cell placed in a uterus is capable of developing into a fetus and a new individual.
• Multipotent cells: Found in adults, these generate specific specialized cells, though research suggests they can sometimes produce different tissue types.

Understanding HIV and AIDS

What is AIDS?

Acquired Immunodeficiency Syndrome (AIDS) is a disease affecting humans infected with HIV. A person is diagnosed with AIDS when their body, due to immunodeficiency caused by HIV, cannot mount an adequate immune response against infections.

History of HIV

The Human Immunodeficiency Virus (HIV) was identified as the agent of the AIDS epidemic by Luc Montagnier's team in France in 1983.

HIV vs. AIDS

A person infected with HIV is HIV-positive. They develop AIDS when their CD4 T-lymphocyte count falls below 200 cells per milliliter of blood.

Methods of Transmission

1. Parenteral: Blood transfusions, needle sharing, etc.
2. Sexual: Homosexual or heterosexual contact.
3. Vertical: Transplacental transmission before birth, during birth, or through breastfeeding.

Common Symptoms

• Rapid weight loss
• Dry cough
• Fever or profuse night sweats
• Profound, unexplained fatigue
• Swollen lymph glands (armpits, groin, or neck)
• Diarrhea lasting over a week
• White spots in the mouth or throat
• Pneumonia
• Red, brown, or pink skin lesions
• Memory loss and depression

Consequences

The effects include physical wasting syndrome and psychological impacts such as depression and loneliness.

Vaccine Research

Scientists in the U.S. and Thailand discovered a vaccine capable of reducing the risk of contracting AIDS with an effectiveness of 31.2%.

The Copenhagen Summit and Ecology

Defining Ecology

Ecology is the study of interrelations between different species and their surrounding environment.

Principles of Sustainability

1. Preserve and protect
2. Find alternatives
3. Critical consumption
4. Be careful
5. Act

Objectives

Short-term: The conclusion of a legally binding global climate agreement, effective from 2012.