These variants then replicate more aggressively with heightened virulence that causes rapid T cell depletion, immune system collapse, and opportunistic infections that mark the advent of AIDS. HIV-positive patients acquire an enormously broad spectrum of opportunistic infections, which was particularly problematic prior to the onset of HAART therapies; however, the same infections are reported among HIV-infected patients examined post-mortem following the onset of antiretroviral therapies. Thus, during the course of infection, viral adaptation to the use of CXCR4 instead of CCR5 may be a key step in the progression to AIDS. A number of studies with subtype B-infected individuals have determined that between 40 and 50 percent of AIDS patients can harbour viruses of the SI and, it is presumed, the X4 phenotypes.HIV-2 is much less pathogenic than HIV-1 and is restricted in its worldwide distribution to West Africa. The adoption of "accessory genes" by HIV-2 and its more promiscuous pattern of co-receptor usage (including CD4-independence) may assist the virus in its adaptation to avoid innate restriction factors present in host cells. Adaptation to use normal cellular machinery to enable transmission and productive infection has also aided the establishment of HIV-2 replication in humans. A survival strategy for any infectious agent is not to kill its host, but ultimately become a commensal organism. Having achieved a low pathogenicity, over time, variants that are more successful at transmission will be selected.
Midol is a brand of over-the-counter analgesic drugs marketed for menstrual cramping and other effects related to premenstrual syndrome and menstruation. Various subbrands are formulated using different active ingredients. Midol is distributed by Bayer. Midol was originally sold in 1911 as a headache and toothache remedy that was considered safer because it did not use the narcotics typically used at the time. It was then promoted as a cure for hiccups claiming it controlled spasms, and finally as a remedy for menstrual cramps and bloating. A formulation sold in the 1980s was made with the sympathomimetic cinnamedrine. It had been reported to have abuse potential as an appetite suppressant and sympathomimetic agent. The "Midol Complete" formulation consists of:

Acetaminophen 500 mg (pain reliever)
Caffeine 60 mg  (stimulant)
Pyrilamine maleate 15 mg (antihistamine)The "Extended Relief" formulation consists of:

Naproxen sodium 220 mg (NSAID, pain reliever/fever reducer)The "Teen" formulation consists of:

Acetaminophen 500 mg (pain reliever)
Pamabrom 25 mg (diuretic)The "Liquid Gels" formulation consists of:

Ibuprofen 200 mg (NSAID, pain reliever)The "PM" formulation consists of:

Acetaminophen 500 mg (pain reliever)
Diphenhydramine citrate 38 mg (sedative antihistamine)There are concerns drugs like Midol, which is an NSAID, increases risk of bleeding, kidney damage and has other negative effects on cardiovascular system. References
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