Related Experiment Video
Updated: Feb 11, 2026

06:46
Isolation of Exosomes from the Plasma of HIV-1 Positive Individuals
Published on: January 5, 2016
17.9K
Cohort study of HIV-positive and -negative methamphetamine users
Journal of the American Dental Association (1939)
|April 25, 2018
Summary
Methamphetamine users, including those with HIV, have a high prevalence of severe periodontal disease. Lifestyle factors, like smoking, appear to be significant contributors alongside methamphetamine use.
Area of Science:
- Oral Health
- Periodontology
- Public Health
Background:
- Methamphetamine (MA) use is linked to dental caries, but its impact on periodontal health is less understood.
- This study investigates periodontal disease in HIV-positive MA users in an urban setting.
Purpose of the Study:
- To determine the prevalence and severity of periodontal disease among HIV-positive MA users.
- To identify risk factors associated with periodontal disease in this population.
Main Methods:
- A cross-sectional survey was conducted in Los Angeles County.
- 541 participants were recruited via street outreach and referrals.
- Periodontal assessments were performed by calibrated dentists.
Main Results:
- High prevalence and severity of periodontal disease were observed in MA users (HIV-positive and -negative).
- Cigarette smoking and older age were identified as significant risk factors.
Conclusions:
- Lifestyle factors, rather than HIV status, appeared to be the primary drivers of destructive periodontal disease in MA users.
- MA users require comprehensive dental care due to extensive periodontal and restorative needs.
Related Concept Videos
Positive, Negative, and Zero Work
22.3K
Work is done on an object when energy is transferred to the object. In other words, work is done when a force acts on a body that undergoes a displacement from one position to another. By definition, the work done by a force is the integral of the force with respect to the displacement along its path. Forces can vary as a function of position, and displacements can occur along various paths between two points. The magnitude of a force multiplied by the cosine of the angle that the force makes...
22.3K
Positive and Negative Feedback Loops
25.4K
Animal organs and organ systems constantly adjust to internal and external changes through a process called homeostasis ("steady state"). Examples of these changes include regulation of the level of glucose or calcium in the blood or internal responses to external temperatures. Homeostasis requires maintaining an internal dynamic equilibrium:
25.4K
Negative Regulator Molecules
38.6K
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
38.6K
Position-effect Variegation
7.1K
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
7.1K
Serial Position Effect
563
The serial position effect is a cognitive phenomenon where individuals are more likely to recall the first and last items in a list compared to those in the middle. This effect is divided into the primacy effect and the recency effect. The primacy effect is observed when the initial items in a list are remembered better. This occurs because these items are rehearsed more frequently or receive more elaborative processing, allowing them to be encoded into long-term memory more effectively. For...
563
Negative and Cognitive Symptoms of Schizophrenia
635
Negative symptoms of schizophrenia indicate a reduction or absence of typical behaviors and emotional responses found in healthy individuals, while positive symptoms reflect an excess or distortion of normal functioning.
Negative Symptoms
Negative symptoms of schizophrenia manifest as deficits in normal emotional and behavioral functioning, profoundly impacting daily life. Individuals with schizophrenia often display a flat affect, characterized by a near-total absence of emotional expression,...
Negative Symptoms
Negative symptoms of schizophrenia manifest as deficits in normal emotional and behavioral functioning, profoundly impacting daily life. Individuals with schizophrenia often display a flat affect, characterized by a near-total absence of emotional expression,...
635

