Cytokines- Mechanism of action and Functions

Cytokines- Mechanism of action and Functions

Cytokines Cytokines are a family of small proteins that mediate an organism’s response to injury or infection. Cytokines operate by transmitting signals between cells in an organism. Minute quantities of cytokines are secreted, each by a single cell type, and regulatory functions in other cells by binding with specific receptors. Their interactions with the receptors produce secondary signals that inhibit or enhance the action of certain genes within the cell. Unlike endocrine hormones, which can act throughout the body, most … Read more

Habitat and Morphology of Chlamydia trachomatis

Habitat of Chlamydia trachomatis It is an obligate intracellular human pathogens. Humans are the only natural host. It cannot survive outside of a eukaryotic host. Chlamydia trachomatis is transmitted by oral, vaginal or anal sex, and can also be transmitted from mother to newborn during a vaginal delivery. They can cause discharge from the penis, pain and burning during urination, infection or inflammation in the ducts of testicles, and tenderness or pain in the testicles. Morphology of Chlamydia trachomatis It … Read more

Protein Structure- Primary, Secondary, Tertiary and Quaternary

Protein Structure- Primary, Secondary, Tertiary and Quaternary

Four levels of hierarchy in protein conformation can be described. A. PRIMARY STRUCTURE PRIMARY STRUCTURE refers to the order of the amino acids in the peptide chain. 1. The free α-amino group, written to the left, is called the amino-terminal or N-terminal end. 2. The free α-carboxyl group, written to the right, is called the carboxyl-terminal or C-terminal end. B. SECONDARY STRUCTURE SECONDARY STRUCTURE is the arrangement of hydrogen bonds between the peptide nitrogens and the peptide carbonyl oxygens of … Read more

What is Immunology?

Immunology

What is Immunology? Immunology is the study of how the body responds to foreign substances and fights off infection and other disease. Immunologists study the molecules, cells, and organs of the human body that participate in this response. Immunity Immunity is a condition of being able to resist a particular disease especially through preventing the development of pathogenic microorganism or by counteracting the effects of its products. Innate immunity is something already present in the body and non-specific. Innate immunity is … Read more

Biochemical Test of Streptococcus canis

Biochemical Test of Streptococcus canis Basic Characteristics Properties (Streptococcus canis) CAMP Negative (-ve) Catalase Negative (-ve) Gram Staining Positive (+ve) OF (Oxidative-Fermentative) Facultative anaerobes Shape Cocci Urease Negative (-ve) VP (Voges Proskauer) Negative (-ve) Fermentation of Adonitol Negative (-ve) Arabinose Negative (-ve) Arabitol Negative (-ve) Arbutin Positive (+ve) Dulcitol Negative (-ve) Erythritol Negative (-ve) Fructose Positive (+ve) Galactose Positive (+ve) Glucose Positive (+ve) Glycogen Negative (-ve) Hippurate Negative (-ve) Inositol Negative (-ve) Inulin Negative (-ve) Lactose Positive (+ve) Maltose Positive … Read more

Characteristics of Fungi

Characteristics of Fungi

Characteristics of Fungi Fungi are eukaryotic organisms means they have true nucleus which are enclosed in membranes. They are non-vascular organisms. They do not have vascular system. Xylem and Phloem are absent. Fungi have cell walls (plants also have cell walls, but animals have no cell walls). There is no embryonic stage for fungi. They reproduce by means of spores. There are sexual and asexual spores. Sexual spores are Oospores, Zygospores, Ascospores, Basidiospores, etc. and Asexual spores are Sporangiospores, Aplanospores, … Read more

Biochemical Test of Providencia stuartii

Biochemical Test of Providencia stuartii

Biochemical Test of Providencia stuartii Basic Characteristics Properties (Providencia stuartii) Capsule Non-Capsulated Catalase Positive (+ve) Citrate Positive (+ve) Flagella Flagellated Gas from glucose Negative (-ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Negative (-ve) Growth in KCN Positive (+ve) H2S Negative (-ve) Indole Positive (+ve) Motility Positive (+ve) MR (Methyl Red) Positive (+ve) Nitrate Reduction Positive (+ve) OF (Oxidative-Fermentative) Fermentative Oxidase Negative (-ve) Pigment Negative (-ve) Shape Rods Spore Non-Sporing Urease Negative (-ve) VP (Voges Proskauer) Negative (-ve) Fermentation of Adonitol … Read more

Aerobic and Facultatively Anaerobic Gram-Positive Cocci

Aerobic and Facultatively Anaerobic Gram-Positive Cocci

Enterococcus faecalis and Enterococcus faecium Clinical Features Urinary tract infections, peritonitis, bacteremia, endocarditis Virulence Factors Relatively avirulent Staphylococcus aureus Clinical Features Suppurative infections: impetigo, folliculitis, furuncles, carbuncles, wounds Disseminated infections: bacteremia, endocarditis, pneumonia, empyema, osteomyelitis, septic arthritis Toxin-mediated infections: toxic shock syndrome, scalded skin syndrome, food poisoning Virulence Factors Possess thick peptidoglycan layer, capsule, protein A, various toxins (cytotoxins, exfoliative toxins, enterotoxins, toxic shock syndrome toxin, Panton- Valentine leukocidin) and hydrolytic enzymes Staphylococcus, coagulase-negative Clinical Features Wound infections, urinary tract … Read more

Biochemical Test of Hafnia alvei

Biochemical Test of Hafnia alvei Basic Characteristics Properties (Hafnia alvei) Capsule Non-Capsulated Catalase Positive (+ve) Citrate Positive (+ve) Flagella Flagellated Gas from Glucose Positive (+ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Negative (-ve) Growth in KCN Positive (+ve) H2S Negative (-ve) Indole Negative (-ve) Motility Motile MR (Methyl Red) Variable Nitrate Reduction Positive (+ve) OF (Oxidative-Fermentative) Fermentative Oxidase Negative (-ve) Pigment Negative (-ve) Shape Rod Spore Non-Sporing Urease Negative (-ve) VP (Voges Proskauer) Positive (+ve) Fermentation of Adonitol Negative (-ve) … Read more