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Mycoplasma Penetrans
''Mycoplasma penetrans'' is a species of Gram-positive bacteria. It is pathogenic, though many infected show no symptoms. It is a sexually transmitted disease, though an infant may be infected during birth. Description It has an elongated shape and its cells possess two internal compartments, one packed with granules, the other filled with coarse granules (consistent with ribosomal structures). The organism has properties of adherence through a specific organelle called the tip organelle. ''M. Penetrans'' has a coding sequence (MYPE1570) similar to that of MYPE470 in ''Mycoplasma pneumoniae'' which codes for an accessory protein that aids in cytadherence, the adherence to respiratory epithelium. This similarity suggests ''M. penetrans'' could attach to host cells through cytadherence. Also, the CDS MYPE1550, which is near MYPE1570, of ''M. penetrans'' is orthologous to the hemadsorption protein HMW2 of ''M pneumoniae'', suggesting the potential for ''M. penetrans'' to attach to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenic
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time frames, but soil has the longest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emerging Infectious Diseases
''Emerging Infectious Diseases'' (EID) is an open-access, peer-reviewed journal published by the Centers for Disease Control and Prevention (CDC). EID is a public domain journal and covers global instances of new and reemerging infectious diseases, putting greater emphasis on disease emergence, prevention, control, and elimination. According to Journal Citation Reports, the journal's 2016 impact factor is 6.99, ranking it 4th out of 82 journals in the infectious disease category. The journal also has a 2016 Google Scholar h5-index score of 79, ranking it 2nd in both the epidemiology category and among open-access epidemiological journals, as well as 4th in the communicable diseases category and 1st among open-access communicable disease journals. Abstracting and Indexing The journal is indexed in PubMed, MEDLINE, Web of Science: Science Citation Index Expanded, and Scopus. The journal has a 2021 impact factor The impact factor (IF) or journal impact factor (JIF) of an ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virulence Factor
Virulence factors (preferably known as pathogenicity factors or effectors in plant science) are cellular structures, molecules and regulatory systems that enable microbial pathogens (bacteria, viruses, fungi, and protozoa) to achieve the following: * colonization of a niche in the host (this includes movement towards and attachment to host cells) * immunoevasion, evasion of the host's immune response * immunosuppression, inhibition of the host's immune response (this includes leukocidin-mediated cell death) * entry into and exit out of cells (if the pathogen is an intracellular one) * obtain nutrition from the host Specific pathogens possess a wide array of virulence factors. Some are chromosomally encoded and intrinsic to the bacteria (e.g. capsules and endotoxin), whereas others are obtained from mobile genetic elements like plasmids and bacteriophages (e.g. some exotoxins). Virulence factors encoded on mobile genetic elements spread through horizontal gene transfer, and ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antigenic Variation
Antigenic variation or antigenic alteration refers to the mechanism by which an infectious agent such as a protozoan, bacterium or virus alters the proteins or carbohydrates on its surface and thus avoids a host immune response, making it one of the mechanisms of antigenic escape. It is related to phase variation. Antigenic variation not only enables the pathogen to avoid the immune response in its current host, but also allows re-infection of previously infected hosts. Immunity to re-infection is based on recognition of the antigens carried by the pathogen, which are "remembered" by the acquired immune response. If the pathogen's dominant antigen can be altered, the pathogen can then evade the host's acquired immune system. Antigenic variation can occur by altering a variety of surface molecules including proteins and carbohydrates. Antigenic variation can result from gene conversion, site-specific DNA inversions, hypermutation, or recombination of sequence cassettes. The res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promoter (genetics)
In genetics, a promoter is a sequence of DNA to which proteins bind to initiate transcription of a single RNA transcript from the DNA downstream of the promoter. The RNA transcript may encode a protein (mRNA), or can have a function in and of itself, such as tRNA or rRNA. Promoters are located near the transcription start sites of genes, upstream on the DNA (towards the 5' region of the sense strand). Promoters can be about 100–1000 base pairs long, the sequence of which is highly dependent on the gene and product of transcription, type or class of RNA polymerase recruited to the site, and species of organism. Promoters control gene expression in bacteria and eukaryotes. RNA polymerase must attach to DNA near a gene for transcription to occur. Promoter DNA sequences provide an enzyme binding site. The -10 sequence is TATAAT. -35 sequences are conserved on average, but not in most promoters. Artificial promoters with conserved -10 and -35 elements transcribe more slowly. Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malignant Pleural Effusion
Malignant pleural effusion is a condition in which cancer causes an abnormal amount of fluid to collect between the thin layers of tissue (pleura) lining the outside of the lung and the wall of the chest cavity. Lung cancer and breast cancer account for about 50-65% of malignant pleural effusions. Other common causes include pleural mesothelioma and lymphoma. Diagnosis Clinical evaluation Clinical factors predicting the diagnosis of malignant pleural effusions are symptoms lasting more than 1 month and the absence of fever. Imaging This is needed to confirm the presence of a pleural effusion. Chest radiograph is usually performed first and may demonstrate an underlying lung cancer as well as the pleural effusion. Ultrasound has a sensitivity of 73% and specificity of 100% at distinguishing malignant pleural effusions from other causes of pleural effusion, based on the presence of visible pleural metastases, pleural thickening greater than 1 cm, pleural nodularity, diaphr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelvic Inflammatory Disease
Pelvic inflammatory disease, also known as pelvic inflammatory disorder (PID), is an infection of the upper part of the female reproductive system, namely the uterus, fallopian tubes, and ovaries, and inside of the pelvis. Often, there may be no symptoms. Signs and symptoms, when present, may include lower abdominal pain, vaginal discharge, fever, burning with urination, pain with sex, bleeding after sex, or irregular menstruation. Untreated PID can result in long-term complications including infertility, ectopic pregnancy, chronic pelvic pain, and cancer. The disease is caused by bacteria that spread from the vagina and cervix. Infections by '' Neisseria gonorrhoeae'' or '' Chlamydia trachomatis'' are present in 75 to 90 percent of cases. Often, multiple different bacteria are involved. Without treatment, about 10 percent of those with a chlamydial infection and 40 percent of those with a gonorrhea infection will develop PID. Risk factors are generally similar to thos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria Described In 1992
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
