var request = null;

   function createRequest() {
     try {
       request = new XMLHttpRequest();
     } catch (trymicrosoft) {
       try {
         request = new ActiveXObject("Msxml2.XMLHTTP");
       } catch (othermicrosoft) {
         try {
           request = new ActiveXObject("Microsoft.XMLHTTP");
         } catch (failed) {
           request = null;
         }
       }
     }

     if (request == null)
       alert("Error creating request object!");
   }

   function getNews() {
     createRequest();
     var url = "includes/envianews.php";
     var email=  document.getElementById("email").value;
     var nome = document.getElementById("nome").value;
     url = url + "?nome=" + nome + "&email=" + email;
     url = url + "&dummy=" + new Date().getTime();
     request.open("GET", url, true);
     request.onreadystatechange = updatePage;
     request.send(null);
  }

  function updatePage() {
    if (request.readyState == 4) {
        if(request.status==200){
              var result = request.responseText;
              alert(result);
        }
    }
  }