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Haemophilus Parainfluenzae
''Haemophilus parainfluenzae'' is a species of'' Haemophilus''. It is one of the HACEK organisms. ''H. parainfluenzae'' is an opportunistic pathogen that has been associated with endocarditis, bronchitis, otitis, conjunctivitis, pneumonia, abscesses and genital tract infections. Natural genetic transformation ''H. parainfluenzae'' biotypes I and II are capable of natural genetic transformation. Natural genetic transformation is a bacterial adaptation for DNA transfer. In order for a bacterium to bind, take up and recombine exogenous DNA into its genome it must enter a special physiological state termed natural competence In microbiology, genetics, cell biology, and molecular biology, competence is the ability of a cell to alter its genetics by taking up extracellular DNA from its environment through a process called transformation. Competence can be differentiat .... In ''H. parainfluenzae'', competence is induced during the late stationary phase of growth. Natural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haemophilus
''Haemophilus'' is a genus of Gram-negative, pleomorphic, coccobacilli bacteria belonging to the family Pasteurellaceae. While ''Haemophilus'' bacteria are typically small coccobacilli, they are categorized as pleomorphic bacteria because of the wide range of shapes they occasionally assume. These organisms inhabit the mucous membranes of the upper respiratory tract, mouth, vagina, and intestinal tract. The genus includes commensal organisms along with some significant pathogenic species such as '' H. influenzae''—a cause of sepsis and bacterial meningitis in young children—and '' H. ducreyi'', the causative agent of chancroid. All members are either aerobic or facultatively anaerobic. This genus has been found to be part of the salivary microbiome. Metabolism Most members of the genus ''Haemophilus'' require at least one of these blood factors for growth: hemin (sometimes called 'X-factor') and/or nicotinamide adenine dinucleotide (NAD; sometimes called 'V-fact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HACEK Organism
The HACEK organisms are a group of fastidious Gram-negative bacteria that are an unusual cause of infective endocarditis, which is an inflammation of the heart due to bacterial infection. HACEK is an abbreviation of the initials of the genera of this group of bacteria: ''Haemophilus'', '' Aggregatibacter'' (previously '' Actinobacillus''), ''Cardiobacterium'', ''Eikenella'', ''Kingella''. The HACEK organisms are a normal part of the human microbiota, living in the oral- pharyngeal region. The bacteria were originally grouped because they were thought to be a significant cause of infective endocarditis, but recent research has shown that they are rare and only responsible for 1.4–3.0% of all cases of this disease. Organisms HACEK originally referred to ''Haemophilus parainfluenzae'', '' Haemophilus aphrophilus'', '' Actinobacillus actinomycetemcomitans'', ''Cardiobacterium hominis'', '' Eikenella corrodens'', and ''Kingella kingae''. However, taxonomic rearrangements have changed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocarditis
Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves. Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or the surfaces of intracardiac devices. Endocarditis is characterized by lesions, known as '' vegetations'', which are masses of platelets, fibrin, microcolonies of microorganisms, and scant inflammatory cells. In the subacute form of infective endocarditis, a vegetation may also include a center of granulomatous tissue, which may fibrose or calcify. There are several ways to classify endocarditis. The simplest classification is based on cause: either ''infective'' or ''non-infective'', depending on whether a microorganism is the source of the inflammation or not. Regardless, the diagnosis of endocarditis is based on clinical features, investigations such as an echocardiogram, and blood cultures demonstrating the presence of endocar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronchitis
Bronchitis is inflammation of the bronchi (large and medium-sized airways) in the lungs that causes coughing. Bronchitis usually begins as an infection in the nose, ears, throat, or sinuses. The infection then makes its way down to the bronchi. Symptoms include coughing up sputum, wheezing, shortness of breath, and chest pain. Bronchitis can be acute or chronic. Acute bronchitis usually has a cough that lasts around three weeks, and is also known as a chest cold. In more than 90% of cases, the cause is a viral infection. These viruses may be spread through the air when people cough or by direct contact. A small number of cases are caused by a bacterial infection such as '' Mycoplasma pneumoniae'' or '' Bordetella pertussis''. Risk factors include exposure to tobacco smoke, dust, and other air pollution. Treatment of acute bronchitis typically involves rest, paracetamol (acetaminophen), and nonsteroidal anti-inflammatory drugs (NSAIDs) to help with the fever. Chronic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otitis
Otitis is a general term for inflammation in ear or ear infection, inner ear infection, middle ear infection of the ear, in both humans and other animals. When infection is present, it may be viral or bacterial. When inflammation is present due to fluid build up in the middle ear and infection is not present it is considered Otitis media with effusion. It is subdivided into the following: * ''Otitis externa'', external otitis, involves inflammation (either infectious or non-infectious) of the external auditory canal, sometimes extending to the pinna or tragus. Otitis externa can be acute or chronic. It can be fungal or bacterial. The most common aetiology of acute otitis externa is bacterial infection, while chronic cases are often associated with underlying skin diseases such as eczema or psoriasis. A third form, malignant otitis externa, or necrotising otitis externa, is a potentially life-threatening, invasive infection of the external auditory canal and skull. Usually associ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjunctivitis
Conjunctivitis, also known as pink eye or Madras eye, is inflammation of the conjunctiva, the thin, clear layer that covers the white surface of the eye and the inner eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may occur. The affected eye may have increased tears or be "stuck shut" in the morning. Swelling of the sclera may also occur. Itching is more common in cases due to allergies. Conjunctivitis can affect one or both eyes. The most common infectious causes in adults are viral, whereas in children bacterial causes predominate. The viral infection may occur along with other symptoms of a common cold. Both viral and bacterial cases are easily spread between people. Allergies to pollen or animal hair are also a common cause. Diagnosis is often based on signs and symptoms. Occasionally, a sample of the discharge is sent for microbial culture, culture. Prevention is partly by handwashing. Treatment depends on the underlying cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumonia
Pneumonia is an Inflammation, inflammatory condition of the lung primarily affecting the small air sacs known as Pulmonary alveolus, alveoli. Symptoms typically include some combination of Cough#Classification, productive or dry cough, chest pain, fever, and Shortness of breath, difficulty breathing. The severity of the condition is variable. Pneumonia is usually caused by infection with viruses or bacteria, and less commonly by other microorganisms. Identifying the responsible pathogen can be difficult. Diagnosis is often based on symptoms and physical examination. Chest X-rays, blood tests, and Microbiological culture, culture of the sputum may help confirm the diagnosis. The disease may be classified by where it was acquired, such as community- or hospital-acquired or healthcare-associated pneumonia. Risk factors for pneumonia include cystic fibrosis, chronic obstructive pulmonary disease (COPD), sickle cell disease, asthma, diabetes, heart failure, a history of smoking, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abscesses
An abscess is a collection of pus that has built up within the tissue of the body, usually caused by bacterial infection. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends beyond the swelling. Carbuncles and boils are types of abscess that often involve hair follicles, with carbuncles being larger. A cyst is related to an abscess, but it contains a material other than pus, and a cyst has a clearly defined wall. Abscesses can also form internally on internal organs and after surgery. They are usually caused by a bacterial infection. Often many different types of bacteria are involved in a single infection. In many areas of the world, the most common bacteria present is ''methicillin-resistant Staphylococcus aureus''. Rarely, parasites can cause abscesses; this is more common in the developing world. Diagnosis of a skin abscess is usually made based on what it looks like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transformation (genetics)
In molecular biology and genetics, transformation is the genetic alteration of a cell resulting from the direct uptake and incorporation of exogenous genetic material from its surroundings through the cell membrane(s). For transformation to take place, the recipient bacterium must be in a state of competence, which might occur in nature as a time-limited response to environmental conditions such as starvation and cell density, and may also be induced in a laboratory. Transformation is one of three processes that lead to horizontal gene transfer, in which exogenous genetic material passes from one bacterium to another, the other two being conjugation (transfer of genetic material between two bacterial cells in direct contact) and transduction (injection of foreign DNA by a bacteriophage virus into the host bacterium). In transformation, the genetic material passes through the intervening medium, and uptake is completely dependent on the recipient bacterium. As of 2014 about 8 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genome
A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as regulatory sequences (see non-coding DNA), and often a substantial fraction of junk DNA with no evident function. Almost all eukaryotes have mitochondrial DNA, mitochondria and a small mitochondrial genome. Algae and plants also contain chloroplast DNA, chloroplasts with a chloroplast genome. The study of the genome is called genomics. The genomes of many organisms have been Whole-genome sequencing, sequenced and various regions have been annotated. The first genome to be sequenced was that of the virus φX174 in 1977; the first genome sequence of a prokaryote (''Haemophilus influenzae'') was published in 1995; the yeast (''Saccharomyces cerevisiae'') genome was the first eukaryotic genome to be sequenced in 1996. The Human Genome Project ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Competence
In microbiology, genetics, cell biology, and molecular biology, competence is the ability of a cell to alter its genetics by taking up extracellular DNA from its environment through a process called transformation. Competence can be differentiated between natural competence and induced or artificial competence. Natural competence is a genetically specified ability of bacteria that occurs under natural conditions as well as in the laboratory. Artificial competence arises when cells in laboratory cultures are treated to make them transiently permeable to DNA. Competence allows for rapid adaptation and DNA repair of the cell. History Natural competence was discovered by Frederick Griffith in 1928, when he showed that a preparation of killed cells of a pathogenic bacterium contained something that could transform related non-pathogenic cells into the pathogenic type. In 1944 Oswald Avery, Colin MacLeod, and Maclyn McCarty demonstrated that this 'transforming factor' was pure DNA. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterial Growth
250px, Growth is shown as ''L'' = log(numbers) where numbers is the number of colony forming units per ml, versus ''T'' (time.) Bacterial growth is proliferation of bacterium into two daughter cells, in a process called binary fission. Providing no mutation event occurs, the resulting daughter cells are genetically identical to the original cell. Hence, bacterial growth occurs. Both daughter cells from the division do not necessarily survive. However, if the surviving number exceeds unity on average, the bacterial population undergoes exponential growth. The measurement of an exponential bacterial growth curve in batch culture was traditionally a part of the training of all microbiologists; the basic means requires bacterial enumeration (cell counting) by direct and individual (microscopic, flow cytometry), direct and bulk (biomass), indirect and individual (colony counting), or indirect and bulk (most probable number, turbidity, nutrient uptake) methods. Models reconcile theor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
