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Ejercicio 1 Análisis de una cuenca vinculado a un evento de tormenta para evaluar el caudal pico

6. SIATL, Simulador de Flujos de Agua de Cuencas Hidrográficas Versión 2.2

7.1 Ejercicio 1 Análisis de una cuenca vinculado a un evento de tormenta para evaluar el caudal pico

 

Collectively,  these  events  allow  for  an  early  response  that  is  not  only  mediated  by  early   proinflammatory  mediators  to  occur  but  for  early  shaping  of  a  long-­‐term  adaptive  response.  As   the  development  of  a  Th1  versus  a  Th2  response  leads  to  development  of  specific  adaptive  re-­‐ sponses  and  different  pathological  outcomes  when  disregulated,  it  is  important  to  look  at  the   Th1/Th2  paradigm  of  secreted  cytokines  after  infection  and  how  it  play  a  roles  in  protection  and   pathogenesis  for  vaccine  development  and  therapeutic  interventions.  Generally  Th1  responses   function  to  drive  cell-­‐mediated  immunity  whilst  the  Th2  responses  influence  the  IgM  to  IgG  and   IgE  antibody-­‐mediated  response.  

The  present  study  was  not  without  its  limitations  and  though  each  MAPK  (JNK  and  p38)   has  a  role  and  can  influence  several  events  including  the  transcriptional  program  within  the  cell   after  infection.  The  effect  observed  in  the  efficiency  of  viral  replication  and  the  levels  and  types   of  cytokines  secreted  in  response  to  the  infection,  suggests  collectively  the  contribution  of  type   differences  and  other  factors  influence  the  overall  outcome  of  the  infection.  It  is  plausible  that   the  effects  of  factors  influenced  by  the  pathway  are  being  inhibited  by  the  IE  and  E  viral  pro-­‐ teins  that  alternate  downstream  targets  of  p38  and  JNK  for  efficient  replication  are  being  af-­‐ fected;   that   the   importance   of   the   transcription   factors   upregulated   in   a   cell-­‐type   and   time-­‐ dependent  manner  are  masked  by  the  culture  system  used  and  that  the  MAPK  network,  which   is  known  like  other  pathways  to  have  areas  of  cross-­‐talk  coupled  with  redundancy  for  regula-­‐ tion,  is  robust  enough  to  mask  the  true  effect  of  inhibition  of  a  select  arm  of  the  pathway.  Also,   though  each  inhibitor  has  specificty  regarding  their  mechanism  of  action,  care  must  be  taken  as   research  has  shown  that  p38  inhibitors  can  activate  or  influence  the  levels  of  activated  JNK  and   as  such  care  must  be  taken  in  extrapolating  information  from  inhibition  the  studies.  However,   with  the  development  of  peptide  based  inhibitors  and  allosteric  modifiers  of  activated  p38  and   JNK  (rather  than  ATP  competitors)  one  may  be  able  to  not  only  have  better  targeting  in  inhibi-­‐ tion  but  also  increase  efficacy.  

7.5 Potential  benefit  of  the  investigated  events  

Virus   infection   leads   to   defined   responses   that   are   host-­‐dependent   and   cell-­‐type-­‐ dependent.  The  infection  leads  to  numerous  manipulations  within  cells  such  that  mRNA,  pro-­‐ teins,  metabolites,  channel  activity  and  potentials  as  well  as  cell  scaffold  structures  and  mem-­‐ branes  are  changed.  All  of  theses  changes  can  be  characterized  as  a  molecular  signature.  The  

changes  are  a  biochemical  signature  of  the  infection  and  they  will  have  certain  alterations  that   are  restricted  to  the  pathogen  in  a  stated  cell  type.  By  investigating  these  signatures  and  dis-­‐ secting  the  role  of  the  pathways  involved,  we  will  not  only  be  able  to  develop  technology  that   can  decipher  what  pathogen  a  cell  type  or  person  has  come  into  contact  with  (diagnostic  appli-­‐ cation)  but  also  be  able  to  define  types  of  proteins  involved  in  specific  biochemical  changes  that   are  either  beneficial  for  the  virus  or  lead  to  detrimental  effects  within  the  host.  

Also  this  work  highlights  the  importance  of  MAPK  signaling  post  infection  and  the  host   dependent  role  factors  regulated  by  the  MAPK  have  in  B  virus  infection.  More  importantly,  the   observed  influence  of  inhibition  on  relative  increases  in  proinflammatory  cytokines  IL6  and  IL8,   again  suggests  that  the  MAPK  p38  and  JNK  may  either  directly  or  indirectly  influence  cytokine   secretion  and  progression  towards  apoptosis  in  host  cells.  The  observed  p38  dampening  of  the   replication  in  the  natural  host,  and  reduction  of  infectious  virus  in  the  foreign  host  after  p38   inhibition  points  to  a  novel  area  not  previously  considered  for  therapeutics  to  B  virus  infection   to  be  investigated.  The  propagation  of  signals  that  lead  to  a  TH1  or  a  TH2  mediated  response   early  after  infection,  can  be  a  means  for  host  survival  and  though  we  generally  associate  TH1   responses  with  antiviral  clearance  early  after  infection,  it  may  be  that  the  host  survival  is  de-­‐ pendant  on  the  TH1  and  TH2  balance  such  that  the  monkey  (as  shown  in  the  data)  is  able  to   express  factors  associated  with  both  responses  and  as  such  has  cellular  immunity  and  humoral   immunity  to  control/limit  the  infection  and  spread  of  B  virus.  

The  overall  induction  of  MAPKs  and  role  of  MAPKs  in  B  virus  infection  has  been  shown  in   this  study  to  occur  in  a  host  dependent  manner,  and  though  not  all  induced  events  are  virus  

specific,  the  study  highlighted  the  importance  of  MAPK’s  in  virus  replication  and  cytokine  secre-­‐ tion,  as  summarized  in  Figure  6.48.  This  regulation  and  modulation  involves  a  constant  shift  in   the  balance  of  transcription  factors  and  cytokines  such  that  their  net  effect  is  dependant  on  the   time  of  release,  the  location  of  the  effect,  the  responsiveness  of  cell  within  the  area  of  the  in-­‐ fection,  the  density  of  receptors  for  the  region  of  its  effect  and  the  overall  composition  of  other   competing  or  synergistic  cytokines  within  the  defined  area.  As  such,  future  studies  to  address   each  of  theses  areas  and  how  the  interaction  of  primary  fibroblast  cells  with  other  circulating   cells  found  in  the  area  post  infection  to  limit  replication  and  spread  will  assist  in  dissecting  the   overall  mechanism  by  which  the  natural  host  is  able  to  control  the  infection  and  survive.  

   

 

   

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