About Virus

1. Define virus. Ans: virus are unicellular ultramicroscopic particles contain either DNA &RNA that reproduce inside the living cell by replication is called virus. General character: 1. Do not process cellular organization. 2. contain one type of nucleic acid either DNA or RNA but never both. 3. Can not grow in culture media. 4. Multiply by replication in to the living cell. 5. Generally resistant to antimicrobial antibiotics. 6. Sensitive to interferon. Morphology of Virus: 1. Size: Viruses are very small in size.(20nm-300nm) 2. Shape: Viruses are are various types of shape – • Bullet • Brick • Sperm • Spherical Structure of virus: The hole virus particle is called virion. 1. Nucleic acid: A central core of nucleic acid(DNA or RNA) is called nucleic acid. 2. Capsid: A central core of nucleic acid surrounded by a protin coat is called capsid. 3. Capsomere: The capsid is composed of subunits is called capsomer. 4. Envlop:Viron may be enveloped or non coat of li...

The human papilloma virus, or human papillomavirus, is more commonly referred to as HPV. The human papilloma virus is a name that represents a group of viruses that includes more than 100 different strains of the virus (see human papilloma virus pictures below). There are more than 100 different types of the human papillomavirus currently known. As commonly believed the human papilloma virus is not a new discovery. The papilloma virus dates back many centuries. Infections with this virus are known throughout the world. This virus is considered to be the most common sexually transmitted disease in the United States. Approximately 20 million people in the United States have the human papilloma virus infection. Human papilloma virus pictures

What does HIV look like? In this computer generated image, the large object is a human CD4+ white blood cell, and the spots on its surface and the spiky blue objects in the foreground represent HIV particles. Outside of a human cell, HIV exists as roughly spherical particles (sometimes called virions). The surface of each particle is studded with lots of little spikes. An HIV particle is around 100-150 billionths of a metre in diameter. That's about the same as: • 0.1 microns • 4 millionths of an inch • one twentieth of the length of an E. coli bacterium • one seventieth of the diameter of a human CD4+ white blood cell. Unlike most bacteria, HIV particles are much too small to be seen through an ordinary microscope. However they can be seen clearly with an electron microscope. HIV particles surround themselves with a coat of fatty material known as the viral envelope (or membrane). Projecting from this are around 72 little spikes, which are formed from the proteins gp120...

Dr Gasson admits that the trial is a proof of principle A British scientist says he is the first man in the world to become infected with a computer virus. Dr Mark Gasson from the University of Reading had a chip inserted in his hand which was then infected with a virus. The device, which enables him to pass through security doors and activate his mobile phone, is a sophisticated version of ID chips used to tag pets. In trials, Dr Gasson showed that the chip was able to pass on the computer virus to external control systems. If other implanted chips had then connected to the system they too would have been corrupted, he said. Medical alert Dr Gasson admits that the test is a proof of principle but he thinks it has important implications for a future where medical devices such as pacemakers and cochlear implants become more sophisticated, and risk being contaminated by other human implants. "With the benefits of this type of technology come risks. We may improve ourse...

HEPATITIS_A Properties A Picornavirus, now classified as a heptovirus, formerly known as enterovirus 72 Naked icosahedral ssRNA virus Genome consists of a single +ve stranded RNA with 7478 nucleotides, which codes for 4 proteins ;- VP1 VP2 VP3 VP4 1 serotype only, although there are 4 genotypes virus can be propagated in primary marmoset cell culture and also in vivo in chimpanzees and marmosets EPIDEMIOLOGY Hepatitis A occurs endemically in all parts of the world, the exact incidence is hard to estimate because of the high proportion of subclinical infections. At least 1.5 million new cases are reported each year. While the actual incidence in developed countries is decreasing, the infection is almost universal in developing countries. Hepatitis A virus (HAV) is a faecal-oral pathogen and transmission is particularly associated with faecally contaminated food and water. Shellfish is particularly notorious as a vehicle for the spread of HAV. In a recent epidemic in Shangh...

Structure and genome of HIV From Wikipedia, the free encyclopedia The genome and proteins of HIV have been the subject of extensive research since the discovery of the virus in 1983.[1][2] The discovery of the virus itself was not until two years after the first major cases of AIDS associated illnesses were reported in 1981.[3][4] Contents [hide] 1 Structure 2 Genome organization 3 RNA secondary structure 4 References 5 External links Structure Figure 1. Diagram of HIV HIV is different in structure from other retroviruses. It is around 120 nm in diameter (around 60 times smaller than a red blood cell) and roughly spherical. HIV-1 is composed of two copies of single-stranded RNA enclosed by a conical capsid comprising the viral protein p24, typical of lentiviruses (Figure 1). The RNA component is 9749 nucleotides long.[5] This is in turn surrounded by a plasma membrane of host-cell origin. The single-strand RNA is tightly bound to the nucleocapsid proteins, p6, p7 and en...