However, because of N. gonorrhoeaes high affinity for horizontal gene transfer, antibiotic-resistant gonorrhea is seen as an emerging public health threat. Serum resistance
As a Gram negative bacteria, N. gonorrhoeae requires defense mechanisms to protect itself against the complement system (or complement cascade), whose components are found with human serum. There are three different pathways that activate this system however, they all result in the activation of complement protein 3 (C3). A cleaved portion of this protein, C3b, is deposited on pathogenic surfaces and results in opsonization as well as the downstream activation of the membrane attack complex. N. gonorrhoeae has several mechanisms to avoid this action. As a whole, these mechanisms are referred to as serum resistance. History
Name origin
Neisseria gonorrhoeae is named for Albert Neisser, who isolated it as the causative agent of the disease gonorrhea in 1878. Galen (130 AD) coined the term "gonorrhea" from the Greek gonos which means "seed" and rhoe which means "flow". Thus, gonorrhea means "flow of seed", a description referring to the white penile discharge, assumed to be semen, seen in male infection. Discovery
In 1878, Albert Neisser isolated and visualized N. gonorrhoeae diplococci in samples of pus from 35 men and women with the classic symptoms of genitourinary infection with gonorrhea – two of whom also had infections of the eyes. In 1882, Leistikow and Loeffler were able to grow the organism in culture.
"Tertiary trisomy" - the extra chromosome is made up of copies of arms from two other chromosomes.Trisomies are sometimes characterised as "autosomal trisomies" (trisomies of the non-sex chromosomes) and "sex-chromosome trisomies." Autosomal trisomies are described by referencing the specific chromosome that has an extra copy. Thus, for example, the presence of an extra chromosome 21, which is found in Down syndrome, is called trisomy 21. Human trisomy
Trisomies can occur with any chromosome, but often result in miscarriage, rather than live birth. For example, Trisomy 16 is the most common trisomy in human pregnancies, occurring in more than 1% of pregnancies; only those pregnancies in which some normal cells occur in addition to the trisomic cells, or mosaic trisomy 16, survive. This condition, however, usually results in spontaneous miscarriage in the first trimester. The most common types of autosomal trisomy that survive to birth in humans are:

Trisomy 21 (Down syndrome)
Trisomy 18 (Edwards syndrome)
Trisomy 13 (Patau syndrome)
Trisomy 9
Trisomy 8 (Warkany syndrome 2)Of these, Trisomy 21 and Trisomy 18 are the most common. In rare cases, a fetus with Trisomy 13 can survive, giving rise to Patau syndrome. Autosomal trisomy can be associated with birth defects, intellectual disability and shortened life expectancy. Trisomy of sex chromosomes can also occur and include:
XXX (Triple X syndrome)
XXY (Klinefelter syndrome)
XYYCompared to trisomy of the autosomal chromosomes, trisomy of the sex chromosomes normally has less severe consequences. Individuals may show few or no symptoms and have a normal life expectancy. See also
Chromosome abnormalities
Aneuploidy
Karyotype
Sexual reproduction
Monosomy

References


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