84 Matching Annotations
  1. May 2017
    1. lipooligosaccharide (LOS) is thought to play a role in inflammation associated with otitis media. All virulent strains produce neuraminidase and an IgA protease, but the role of these extracellular enzymes in invasion is unproven. Fimbriae increase the adherence of bacteria to human mucosal cells in vitro, and they are required for successful colonization of the nasopharynx. The Anton antigen, as defined in red blood cells, appears to be the receptor.

      Virulence for haemophilus

    1. It has several virulence factors that play a crucial role in patient infl ammatory response. Its capsule, the adhesion proteins, pili, the outer membrane proteins, the IgA1 protease and, last but not least, the lipooligosaccharide, increase the virulence of H. infl uenzae by participating actively in the host invasion the host by the microrganism.

      Virulence Factors

    1. The pathogenesis of H. influenzae infections is not completely understood, although the presence of the capsule in encapsulated type b (Hib), a serotype causing conditions such as epiglottitis, is known to be a major factor in virulence. Their capsule allows them to resist phagocytosis and complement-mediated lysis in the nonimmune host. The unencapsulated strains are almost always less invasive; they can, however, produce an inflammatory response in humans, which can lead to many symptoms.

      Virulence of Haemophilus

    1. Amoxicillin, a type of penicillin, used to be the main antibiotic used for sinusitis but it has become less effective. Amoxicillin-clavulanate (Augmentin, generic) has replaced amoxicillin as the antibiotic recommended for treating acute bacterial sinusitis in both children and adults. It is a type of penicillin that works against a wide spectrum of bacteria.

      Antibiotic Treatment

    2. The elderly are at specific risk for sinusitis. Their nasal passages tend to dry out with age. In addition, the cartilage supporting the nasal passages weakens, causing airflow changes. They also have diminished cough and gag reflexes and weakened immune systems and are at greater risk for serious respiratory infections than are young and middle-aged adults.

      Elderly risk factors

  2. www.life.umd.edu www.life.umd.edu
    1. First, the presence of cell wall receptors enables K. pneumoniae to attach to the host cell, thereby altering the bacterial surface so that phagocytosis by polymorphonuclear leukocytes and macrophages is impaired and invasion of the non-phagocytic host cell is facilitated. Second, invasion of the host cell is also facilitated by the large polysaccharide capsule surrounding the bacterial cell; in addition this capsule acts as a barrier and protects the bacteria from phagocytosis. Third, K. pneumoniae produces an endotoxin that appears to be independent of factors that determine receptors and capsular characteristics.

      Virulence factors

    1. When bacteria such as Klebsiella pneumoniae produce an enzyme known as a carbapenemase (referred to as KPC-producing organisms), then the class of antibiotics called carbapenems will not work to kill the bacteria and treat the infection. Klebsiella species are examples of Enterobacteriaceae, a normal part of the human gut bacteria, that can become carbapenem-resistant. CRE, which stands for carbapenem-resistant Enterobacteriaceae, are a family of germs that are difficult to treat because they have high levels of resistance to antibiotics. Unfortunately, carbapenem antibiotics often are the last line of defense against Gram-negative infections that are resistant to other antibiotics.

      Mechanism of action/resistance?

    2. Patients whose care requires devices like ventilators (breathing machines) or intravenous (vein) catheters, and patients who are taking long courses of certain antibiotics are most at risk for Klebsiella infections. Healthy people usually do not get Klebsiella infections.

      Increased risk

    1. F. necrophorum contains particulary powerful endotoxic lipopolysaccharides in its cell wall and produces a coagulase enzyme that encourages clot formation. Additionally, it produces a variety of exotoxins, including leukocidin, hemolysin, lipase, and cytoplasmic toxin, all of which likely contribute to its pathogenicity.

      Toxins and mechanism of action

    1. Lemierre's syndrome occurs most often when a bacterial (e.g. Fusobacterium necrophorum) throat infection progresses to the formation of a peritonsillar abscess. Deep in the abscess, anaerobic bacteria can flourish. When the abscess wall ruptures internally, the drainage carrying bacteria seeps through the soft tissue and infects the nearby structures.

      Serious cases where F. necrophorum spread leads to Lemierre's Syndrome

  3. Apr 2017
    1. They typically cause significant infection only when the oral mucosa is significantly disrupted and host defense mechanisms are compromised, for example, in neutropenic patients with cancer

      Virology

    1. MERS

      "Middle East respiratory syndrome coronavirus is a viral respiratory illness that was first reported in Saudi Arabia, in 2012. Symptoms are those of a severe, acute, respiratory illness, similar to pneumonia. All known cases so far have been linked to travel or residence in and around the Arabian Peninsula...There is currently no vaccine or cure for MERS-CoV, and so far it has been fatal in around 36 percent of cases. As coronaviruses tend to mutate, there are concerns that MERS could become a pandemic."(Nichols, Medical News Today).

      http://www.medicalnewstoday.com/articles/262538.php

      "

    2. unsafe burial practices, which involve washing and preparing the body of the deceased, apparently contributed to the infection of many people who were participating in this cultural practice

      Highlights the value of understanding other cultures/values in medicine. In 2014, the president of Liberia ordered that all Ebola victims were to be cremated rather than buried (The Guardian). Even though this was ordered, many people still continued to have secret burials out of respect of their loved ones and traditions. Across various countries in Africa, people had to change their cultural practices or risk spreading Ebola further (Maxmen, National Geographic).<br> References: https://www.theguardian.com/world/2014/oct/24/ebola-cremation-ruling-secret-burials-liberia

      http://news.nationalgeographic.com/2015/01/150130-ebola-virus-outbreak-epidemic-sierra-leone-funerals/

    3. In the film, a fictional deadly virus sweeps the world after migrating from a dead pig to a chef that handles it.

      I watched the film after reading this article, it definitely made me more aware of the surfaces I was touching and the amount of times I touched my face during the day.

    4. incorrect impression about how the disease emerges in the first place and, on the other hand, insinuate that somebody should be blamed for this outbreak, when that's not really appropriate,"

      Gaetan Dugas was vilified for being identified as patient zero in the spread of HIV and AIDS. While it is useful to know the origins of a disease in order to figure out how it spreads, the point of index cases is not to place blame. With multiple routes of disease transmission and entry, some people are just more susceptible to illness from the bacteria and viruses on the surfaces people come in contact with.

    5. "patient zero" lives on, and continues to create confusion and curiosity about how disease spreads.

      Patient zero does not exist and is not real. People associate patient zero with being the person where the disease originates as a host. Index case is the correct term to use. It is the first case with the disease that can be identified and traced back to.