Pharmaceutical Agents: Mechanisms, Development, and Resistance
Anticancer Drugs: Mechanisms and Resistance
Anticancer drugs, also known as chemotherapy agents, are pharmacological substances designed to treat malignant diseases by inhibiting the growth and proliferation of cancer cells. These drugs operate through various mechanisms, targeting specific cellular processes essential for cancer cell survival and replication. The primary goals of anticancer therapies include damaging the DNA of cancer cells, inhibiting the synthesis of new DNA strands, and disrupting
Read MoreUnderstanding Food Browning: Maillard Reaction and Enzymatic Processes
Food Browning: Types and Mechanisms
Overview of Food Changes
Food undergoes various changes that can affect its quality, safety, and appearance. These changes can be broadly categorized as physical, chemical, or biotic.
Physical Factors
- UV Light
- Oxygen
- Temperature
- pH
Chemical Factors
- Oxidation of lipids
- Browning reactions
- Toxic pollutants
- Natural additives
Biotic Factors
- Microbiological activity
- Parasitological contamination
The Maillard Reaction: Non-Enzymatic Browning
Definition and Characteristics
The Maillard
Read MoreOrganic Chemistry: Carboxylic Acids, Amines, and Heterocycles
Unit 1: Carboxylic Acids and Their Derivatives
Preparation of Carboxylic Acids
Oxidation Reactions
- Primary alcohols → Carboxylic acids (using KMnO4, CrO3, etc.)
- Aldehydes → Carboxylic acids
- Ketones (via haloform reaction in methyl ketones)
Ester Hydrolysis
- Acidic hydrolysis: RCOOR’ + H2O → RCOOH + R’OH
- Alkaline hydrolysis (saponification): RCOOR’ + OH− → RCOO− + R’OH
Important Reactions of Carboxylic Acids
Hell-Volhard-Zelinsky Reaction
- α-halogenation of carboxylic acids using Br2 + PBr3
- Mechanism:
Cellular Transport and Plasma Membrane Structures
Macrotransport: Cellular Uptake and Release
Characteristics of Macrotransport
- Transport of large molecules/particles into and out of the cell
- Involving deformation/folding of the plasma membrane
Types of Macrotransport
- Endocytosis: Transport into the cell
- Pinocytosis (“cell drinking”)
- Phagocytosis (“cell eating”)
- Exocytosis: Transport out of the cell
Endocytosis
Phagocytosis vs. Pinocytosis: Key Differences
- Size of the material engulfed:
- Phagocytosis: > 250 nm vacuoles
- Pinocytosis: < 150 nm vesicles
- Size
Stem Cells: Understanding Types and Therapeutic Potential
Understanding Stem Cells: Types and Applications
A stem cell is an undifferentiated cell that can self-renew and differentiate into various specialized cell types. Stem cells serve as a continuous source for the diverse cells that constitute the tissues and organs of animals and plants. There is significant interest in stem cells due to their powerful potential for developing therapeutic approaches to replace damaged or diseased cells resulting from various disorders and injuries.
Stem cells are totipotent
Read MoreDNA Sequencing Technologies: Methods and Applications
DNA Sequencing Methods and Technologies
Classical Sequencing: The Sanger Method
DNA sequencing methodologies can typically be classified into two major categories: classical sequencing techniques and high-throughput sequencing approaches. A prime example of the classical approach is the Sanger sequencing method. First introduced in 1977 by British biochemist Frederick Sanger and his colleagues, Sanger sequencing holds the distinction of being among the earliest DNA sequencing technologies.
This technique
Read More