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290                              Jose M. Prieto

                       Antiviral Activities
                          Viruses are still a major, poorly addressed challenge in medicine. The prediction of
                       antiviral  properties  of  chemical  entities  or  the  optimisation  of  current  therapies  to
                       enhance  patient  survival  would  be  of  great  impact  but  the  application  of  AI  to  this
                       conundrum has been less explored than in the case of antibacterials. Perhaps the most
                       pressing issue is the search for improved combination, antiretroviral drugs to suppress
                       HIV  replication  without  inducing  viral  drug  resistance.  The  choice  of  an  alternative
                       regimen may be guided by a drug-resistance test. However, interpretation of resistance
                       from  genotypic  data  poses  a  major  challenge.  Larder  and  co-workers  (2007)  trained
                       ANNs with genotype, baseline viral load and time to follow-up viral load, baseline CD4+
                       T-cell  counts  and  treatment  history  variables.  These  models  performed  at  low-
                       intermediate level, explaining 40-61% of the variance. The authors concluded that this
                       was  still  a  step  forward  and  that  these  data  indicate  that  ANN  models  can  be  quite
                       accurate  predictors  of  virological  response  to  HIV  therapy  even  for  patients  from
                       unfamiliar clinics.
                          We recently tried to model the activity of essential oils on herpes viruses (types 1 and
                       2) by both MLR and ANNs (Tanir & Prieto, unpublished results). Our results could not
                       find a clear subset of chemicals with activity, but rather the best results were given by
                       datasets  representing  all  major  components.  This  highlights  that  viruses  are  a  much
                       harder problem to model and more work must be done towards solving it.


                       Prediction of Pharmacological/Toxicological Effects and Disease Biomarkers

                          The  prediction  of  pharmacological  or  toxicological  effects  should  ideally  involve
                       whole living organisms or at least living tissues. However, the current approach is the use
                       of culture mammal cells, favouring single proteins as targets. Therefore, predicting these
                       effects is clearly more complex than the prediction of purely chemical reactions (such as
                       antioxidant activities) or antimicrobial ones (bacteria, fungi, viruses).
                          Inflammation  is  the  response  of  a  living  tissue  to  an  injury.  Therefore,  is
                       fundamentally  a  multifactorial  process  which  may  pose  extreme  complexity  on  its
                       modeling. An approximation to the problem is to target the inhibition of key enzymes
                       responsible for the onset and maintenance of such process such as cyclooxygenases and
                       lipoxygenases. Nonsteroidal anti-inflammatory drugs inhibiting either of those targets are
                       the  most  used  anti-inflammatory  medicines  in  the  world.  Dual  inhibitors  of
                       cyclooxygenase-1 and 5-lipoxygenase are proposed as a new class of anti-inflammatory
                       drugs with high efficacy and low side effects. In a recent work, Chagas-Paula and co-
                       workers (2015) selected c.a. 60 plant leaf extracts from Asteraceae species with known in
                       vitro  dual  inhibition  of  cyclooxygenase-1  and  5-lipoxygenase  and  analyzed  them  by
                       HPLC-MS-MS analysis. Chromatographic peaks of the extracts were correlated to their
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