Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Sputum Studies I: Gram Stain, cytology, and Acid-fast smear and culture

Sputum Studies I: Gram Stain, cytology, and Acid-fast smear and culture

Sputum studies are a critical part of diagnosing and treating numerous respiratory conditions. These studies involve obtaining sputum samples for analysis to identify pathogenic organisms and assess the presence of abnormal cells indicative of malignant conditions. This lesson will delve into three fundamental sputum studies: Gram Stain, Cytology, and Acid-fast Smear and Culture.
Gram Stain
The Gram Stain is an integral part of sputum studies. It involves the staining of sputum, which permits...

Sputum Studies II: Culture and Sensitivity

Sputum Studies II: Culture and Sensitivity

Description
Sputum culture and sensitivity is a medical procedure used to diagnose bacterial infections in the respiratory tract and select the most appropriate antibiotics for treatment. This process involves analyzing sputum samples of thick and opaque secretions produced in the lungs and airways. These samples are collected from patients and then sent to the laboratory for analysis.
The test can identify various pathogens responsible for respiratory infections, including Streptococcus,...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Suprachiasmatic nucleus function and circadian entrainment are modulated by G protein-coupled inwardly rectifying (GIRK) channels.

The Journal of physiology·2014

Same author

Disruption of circadian rhythmicity and suprachiasmatic action potential frequency in a mouse model with constitutive activation of glycogen synthase kinase 3.

Neuroscience·2012

Same author

Nathan Smith and Typhoid Fever.

The Yale journal of biology and medicine·2011

Same author

Type I Pneumococcus Otitis Media: (A Case Report and Discussion).

The Yale journal of biology and medicine·2011

Same author

Comparative Statistical Analyses of the 1916 and 1931 Epidemics of Poliomyelitis in and About the City of New Haven.

The Yale journal of biology and medicine·2011

Same author

A Note on the Early History of Infantile Paralysis in the United States.

The Yale journal of biology and medicine·2011

Search research articles

Related Experiment Video

Updated: Jun 19, 2026

Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay

Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay

Published on: April 28, 2014

A COMPARATIVE STUDY OF SMOOTH AND ROUGH PNEUMOCOCCUS COLONIES.

¹Ayer Clinical Laboratory, Pennsylvania Hospital, Philadelphia.

The Journal of Experimental Medicine

|October 30, 2009

Summary

This study reviews pneumococcus colony appearances, distinguishing between S and R types. R pneumococci colonies show distinct characteristics, unlike S pneumococci, which can exhibit temporary changes.

Area of Science:

Microbiology
Bacteriology

Background:

Pneumococci exist in two colony forms: Smooth (S) and Rough (R).
Distinguishing between these forms is crucial for understanding pneumococcal behavior and pathogenesis.

Purpose of the Study:

To detail the characteristic colony morphologies of S and R pneumococci.
To differentiate true R pneumococci from transiently altered S pneumococci based on colony appearance and autolysis.

Main Methods:

Culturing Streptococcus pneumoniae (pneumococci) on rabbit blood agar for 24 and 48 hours.
Microscopic examination and macroscopic observation of colony morphology.
Assessing the rate of colony autolysis over 48-96 hours.

Main Results:

R pneumococci colonies exhibit distinct structures and do not rapidly autolyze within 48-96 hours.

More Related Videos

Experimental Human Pneumococcal Carriage

Experimental Human Pneumococcal Carriage

Published on: February 15, 2013

A Mouse Model for the Transition of Streptococcus pneumoniae from Colonizer to Pathogen upon Viral Co-Infection Recapitulates Age-Exacerbated Illness

A Mouse Model for the Transition of Streptococcus pneumoniae from Colonizer to Pathogen upon Viral Co-Infection Recapitulates Age-Exacerbated Illness

Published on: September 28, 2022

Related Experiment Videos

Last Updated: Jun 19, 2026

Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay

Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay

Published on: April 28, 2014

Experimental Human Pneumococcal Carriage

Experimental Human Pneumococcal Carriage

Published on: February 15, 2013

A Mouse Model for the Transition of Streptococcus pneumoniae from Colonizer to Pathogen upon Viral Co-Infection Recapitulates Age-Exacerbated Illness

A Mouse Model for the Transition of Streptococcus pneumoniae from Colonizer to Pathogen upon Viral Co-Infection Recapitulates Age-Exacerbated Illness

Published on: September 28, 2022

S pneumococci colonies typically undergo rapid autolysis.

Transient "pseudo rough" colonies from S pneumococci under suboptimal conditions do not represent true dissociation into R forms.

Conclusions:

Colony morphology and autolysis rates are key differentiating features between S and R pneumococci.
Careful observation is needed to distinguish true R pneumococci from S pneumococci exhibiting temporary morphological changes.