TYPHOID

          

            Typhoid fever is a bacterial infection caused by Salmonella enterica. It is also termed as enteric fever. It is a highly contagious disease. Typhoid can be fatal if it is not attended too quickly.  It is transmitted by the ingestion of food or water contaminated with bacterium Salmonella. Typhoid is also transmitted through the feces of an infected person. Common symptoms include high or slow fever, profuse sweating and gastroenteritis. Typhoid fever is a common worldwide illness. It can affect any person irrespective of health, background and race. There are 1000 different types of typhoid bacteria. Various drugs used to treat typhoid are unsuccessful against resistant strains of typhoid bacteria. In developing country such as India, it is a great threat and a major cause of death. Typhoid disease mainly hit on children who are in school-going age. It is not very common in adults and older people.

         Bacteria of typhoid are survived in unhygienic conditions. These bacteria are spread by typhoid patients and carriers in large quantities through stools and vomit. The bacteria then travel to food, drinks and water through house-flies and other insects. Such foods are contaminated. When these contaminated food or drinks, are taken by healthy person, bacteria enter in to the body of person and causes typhoid fever. Person may get typhoid fever by consuming food or drink that has been carried by someone having the bacteria, or if sewage contaminated with S.typhi gets into water used for drinking or washing food. There are 107 different strains of this bacterium.

       Paratyphoid is caused by Salmonella enteritidis paratyphi A, B or C. It is generally a less infection than typhoid. A very low percent of typhoid patients remain chronic carriers regardless of treatment. Most common complications are intestinal bleeding and perforation. The source of fever is polluted water. In India, due to population explosion, water is polluted and this disease is matter of worry especially in disaster areas, where water supply and sewage disposal are disrupted. Raw vegetables grown on sewage fields also spread infection. The bacteria can survive in soil and water for several months. They grow rapidly in milk and milk-products.

         Typhoid cases are more common in developing countries due to unhygienic conditions. Early and most common symptoms include fever, malaise, abdominal pain and severe diarrhea which could worse conditions more. Other symptoms include abdominal tenderness, bloody stools, chills, confusion, nose bleeding, lethargic feeling and weakness.

         Salmonella causes three clinical syndromes in human being they are enteric fever, gastroenteritis and septicemia. Bacteria usually enters the body through mouth by the  contaminated food or water. Once bacteria resist host defense mechanism and manage to penetrate intestinal wall and multiplies in great number. Within 24 hours to 72 hours bacteria tries to enter into bloodstream causing septicemia and systemic infection.

           Salmonella multiplies in gall bladder abundantly and is discharged continuously into the intestine where it involves Peyers’s Patches and Lymphoid follicles. These become inflamed and undergo necrosis and slough off, leaving behind the characteristic typhoid ulcers. Ulceration of bowels leads to complication known as intestinal perforation and hemorrhage. Onset is usually gradual with headache, abdominal discomfort, lethargic etc. The typical feature is step ladder pyrexia.

         Apart from intestinal perforation and hemorrhage other complications involved is circulatory collapse. Some degree of bronchitis or bronchopneumonia is always found. Some develop psychoses, deafness or meningitis. Cholecystitis, abscesses, arthritis, periosteistis, nephritis, hemolytic anemia, venous thromboses and peripheral neuritis are other complications found. The number of such symptoms involved is quiet less but fatality rate is very high.

Treatment  

               As it is said for all diseases, prevention is the best remedy. For typhoid, proper antibiotics have to be used. There is a growing frequency of resistant strains of the bacteria. Other treatment is to reduce symptoms through drinking more fluids. This prevents the dehydration that results from a prolonged fever and diarrhea. If a patient is severely dehydrated, he may need to receive fluids intravenously. Patient must take a healthy diet. Typhoid fever in most cases is not fatal. Antibiotics, such as ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, amoxicillin and ciprofloxacin, have been commonly used to treat typhoid fever in microbiology. Even after treatment with antibiotics, some people who recover from typhoid fever continue to carry the bacteria in their intestinal tract or gallbladder for years. Such people called chronic carriers. They carry the bacteria in their feces and are capable of infecting others, although they no longer have signs or symptoms of the disease themselves.

GENE- what are they...???

        
         The children acquire the characteristic features of theirs parents. The inheritance of these hereditary characters can be explained on the basis of ancestral genes that are found to be arranged on chromosomes, and they make the total genetic make-up of the organism.

        But the question arises, What are gene? What are genes chemically composed of and their functions and how are they transmitted to the offspring's?

        The hereditary units which are transmitted from one generation to another are called genes. It is a fundamental biological unit which is called as functional factor of heredity.

        These characters are transmitted from parents to the offspring's during reproduction which forms the basis of maintaining continuity of a species. Genes responsible for transmission are located on chromosomes and through the gametes enter a diploid zygote cell which occurs in all sexually reproducing organisms. Thus, each offspring's receives 50% genes from male parent and the remaining 50% from the female parent during fusion of gametes to form zygote.

ON THE BASIS OF MODERN CONCEPT OF GENETIC KNOWLEDGE :

Genetics material of any organism is the substance that carries genetic information determining the properties of that organism. The genetic material is also responsible for transferring genetic material from parent to their offspring's.

CHARACTERISTICS OR PROPERTIES OF GENETIC MATERIAL :

Genes are linearly arranged segments of DNA molecule, which determines the inheritance and expression of particular hereditary characters. The principle criteria material should therefore:

1. Possesses the ability to store and express genetic information and also transmit as required.

2. Possesses the ability to make its own replica so that a copy of it may be transmitted to the offspring.

3. Possesses the ability to transfer its information from parent cell to daughter cells with least minimal error.

4. Maintains physical and chemical stability in order to prevent loss of genetic information.

5. Possesses the capability for genetic change without major loss of parental information which generates the biological variations essential for evolution.

IRON EATING BACTERIA CAN EAT ELECTRICITY INSTEAD

         

         Scientist have developed a way to grow iron oxidizing bacteria using electricity instead of iron, an advance that will allow them to better study the organism and could one day be used to turn electricity into fuel. The study will be published in mBio.


         The method, called electrochemical cultivation, supplies these bacteria with a steady supply of electrons that the bacteria use to respire or 'breathe'. It opens the possibility that one day electricity generated from the sources like wind or solar could be funneled to iron oxidising bacteria that combine it with carbon dioxide to create biofuels, capturing the energy as a useful, storable substances.


          "Its a new way to cultivate a microorganism that's been difficult to study. But the fact that these organisms can synthesize everything they need using only electricity," says Daniel Bond of the University of Minnesota.


           To 'breathe', iron oxidisers take electrons off of dissolved iron, called Fe (II) - a process that produces copious amounts of rust, called Fe (III). Iron oxidising bacteria are found around world. Scientist think these bacteria must carry out the iron oxidation step on their surfaces. If that's true, Bond reasoned, the outsides of the organisms should be covered with proteins that interact with Fe (II), so you should be able provide a stream of pure electrons to the outsides and get them to grow.


            Bond and his colleagues added the marine iron oxidiser Mariprofundus ferrooxydans PV -1, along with some nutrient medium, to an electrode carefully tuned to provide electrons at the same energy level, or potential, as Fe (II) would provide. The idea, says Bond, was to "fool the bacteria into thinking they're at the world's best buffet of Fe (II) atoms."


            It worked. The bacteria multiplied and formed a film on the electrode, Bond says, and eventually they were able to grow M ferrooxydans with no iron in the medium.


            "Bacteria are experts at the capture of carbon dioxide. They build cells and compounds" with the carbon, he says. They might one day be exploited as microscopic energy packagers : Bacteria like M ferrooxydans could capture electricity from an electrode, combine it with carbon dioxide and package it as a carbon rich compound we could use as fuel.

Article from MUMBAI MIRROR NEWSPAPER

AUSTRALIAN EXPERTS OFFER HOPE FOR AIDS CURE

Tweaking Virus Protein Can Shield Cells From Contracting HIV Infection

          In a break through, Australian researchers claim to have discovered how to modify a protein in Human Deficiency Virus ( HIV) which could lead to a potential cure for Acquired immunodeficiency Syndrome (AIDS).

         According to researcher David Harrich from Queensland Institute of Medical Research, the protein can be modified so that instead of replicating, it protects against the deadly infection.

          "I consider that this is fighting fire with fire. What we've actually done is taken a normal virus protein that the virus needs to grow, and we've changed this protein, so that instead of assisting the virus, it actually impedes virus replication and does it quite strongly," Harrich said.

         He added that modified protein cannot cure HIV but it has protected human cells from AIDS in the laboratory.

       "This is therapy is potentially a cure for AIDS. So it's not a cure for HIV infection, but it potentially could end the disease," he said. Over 30,000 people have been diagnosed with HIV in Australia.

        If clinical trails are successful  one treatment could be effective enough to replace the multiple therapies they currently need.

        "Drug therapy targets individual enzymes or proteins and they have one drug, one protein. He added that they have to take two or three drugs, so this would be a single agent that essentially has the same effect. "So in that respect, this is world first agent at multiple steps of the virus life cycle," he added.

      He said that the new treatment has the potential to make big improvements in the quality of life for those carrying HIV. "I think what people are looking for is basically a means to go on and lives with as little intrusion as possible. You either have to eliminate the virus infection or alternatively you have to eliminate the disease process and that's what this could do, potentially for a very long time, Harrich said.

     Harrich added that animal rials are due to start this year and early indications are positive.

NEW TECH HELPS SPOT CANCER SPREAD

IT  WILL  ALLOW  SURGEONS  TO  REMOVE  TUMOURS  &  SAVE HEALTHY  CELLS  IN  PATIENTS

            Researchers have developed a new technique that will allow surgeons to identify how far the tumour has spread and help them decide which tissue to remove in order to save healthy cells in cancer patients.

          "With molecular-targeted imaging, surgeons can avoid unnecessary removal of healthy lymph nodes which is better long-term for patients." said Quyen T Nguyen, associate professor at University of California, San Diego School of Medicine. "The range of the surgeon's visual field is greatly enhanced by a molecular tool that can help achieve accurate surgical margins and detection of metastases so that no tumour is left behind," Nguyen said.

         Lymph nodes, located throughout the body, serve as filters that contain immune cells to fight infection and clean the blood. When cancer cells break away from a tumour, the cells can travel through the lymph system and hide in these tiny organs. 

        Surgeons remove the nodes to determine if a cancer has spread. However, human nodes, only half a centimeter in size, are difficult to discern among the surrounding issue during surgery.

       Furthermore, even when surgeons are able to map the location of the nodes, there is no current technique that indicates whether or not the lymph nodes contain cancer, requiring removal of more lymph nodes than necessary.

        "This research is significant because it shows real time intra-operative detection of cancer metastases in mice. In the future, surgeons will be better able to detect and stage cancer that has spread to the patient's lymph nodes using molecules that were designed and developed at UC San Diego," he said.

          The fluorescently labelled molecules, know as ratiometric activatable cell-penetrating peptides (RACPP), are injectable. When used in mouse models, surgeons could see where the cancer had spread with high sensitivity and specificity even when the metastatic sites were only a few millimeters in size. 

WHAT IS MICROBIOLOGY...???

Actually this should have been my first post but never the less. I am sharing this so that many would know what is MICROBIOLOGY.

             

         Microbiology is the study of living organism about microscopic size, which includes bacteria, fungi, algae  protozoa and the infectious agents at the borderline of life that are called as viruses. The field is concerned with their form, structure, classification, metabolism, physiology and their distribution in environment.  To relate each of organism with each other, with environment, with other species and of-course with plants, animals and humans. The field  notes the physical, chemical and biological changes in environment.

          Microorganism have a major role to play with human health and its welfare. When various organism are taken into consideration, some organisms have beneficial effect while some have harmful effect. Organisms which are involved in making of cheese, beer, wine, vinegar, antibiotic production, curd etc are beneficial organisms. While microorganism which are responsible for food spoilage, diseases or deteriorating things like iron pipes, lenses, wood etc are harmful organisms.

         Most of microorganisms are unicellular i.e. one single cell. All the metabolism, processes for living are performed by a single cell.When compared to any multicellular organism, they have different organs and tissues which are specific for various functions. Thus one cell is capable of performing all activities necessary for its survival. Thus complexity in cell functioning is too high.

         The word cell was first used more than two centuries ago by an Englishman ROBERT HOOKE ( 1635-1703 ). Later the concept of the cell as the structural unit of life - The Cell Theory_ is credited to two Germans _ MATTHIAS SCHLEIDEN & THEODOR SCHWANN, who in 1838-1839 describe cells as the basic structural and functional unit of all organisms.

          Any kind of organisms may be present, either unicellular or multicellular, all biological system have the following characteristics in common- 1. The ability to reproduce, 2. The ability to ingest or assimilate food substances and metabolize them for energy and growth, 3.The ability to excrete waste products, 4. The ability to react to changes in the environment and 5. Susceptibility to mutation.

         Thus, a microbiologist work is large and on many parameters. As it is said "THE NEXT SMALL THING IS BIG"...!!!

PLANT CELL

HOPE OF TREATING CANCER

SCIENTISTS CREATE TUMOUR-KILLING CELLS WHICH CAN BE DIRECTLY INJECTED INTO PATIENTS

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         In a breakthrough, scientists have for the first time created cancer-killing cells which can be directly injected into patients. Researchers in Japan have created cancer-specific killer T-cell, the cells naturally occur in small numbers, but it is hoped injecting huge quantities back into a patient could turbo-charge the immune system.

         Researchers at the RIKEN Research Centre for Allergy and Immunology revealed they have succeeded for the first time in creating cancer-specific, immune system cells called killer T lymphocytes.

        To create these, the team first had to reprogramme T lymphocytes specialized in killing a certain type of cell called induced pluripotent stem cell (iPS cells). These iPS cells then generated fully active, cancer-specific T lymphocytes. These lymphocytes regenerated from iPS cells could potentially serve as cancer therapy in the future, researchers believe.

        Previous research has shown that killer T lymphocytes produced in the lab using conventional methods are inefficient in killing cancer cells mainly because they have a very short life-span, which limits their use as treatment for cancer.

        To overcome the problems, Japanese researchers, led by Hiroshi Kawamoto reprogrammed mature human killer T lymphocytes into iPS cells and investigated how these cells differentiate. The team induced killer T lymphocytes specific for a certain type of skin cancer to reprogram into iPs cells by exposing the lymphocytes to the “Yamanaka factors” – a group of compounds that induce cells to revert to a non specialized, stage.

        The iPS cells obtained were then grown in the lab and induced to differentiate into killer T lymphocytes again. This new batch of T lymphocytes was shown to be specific for the same type of skin cancer as the original lymphocytes.

        They maintained the genetic reorganization, enabling them to express the cancer-specific receptor on their surface. The new T lymphocytes were also shown to be active and to produce an anti-tumour compound.

“We have succeeded in the expansion of antigen-specific T cells by making iPS cells and differentiating them back into functional T cells.” Kawamoto said.