title: How to make beta italic and bold in axis label and P italic and bold in text
body: <pre><code>x&lt;-c(0.2,0.4,0.8,2.3)
  y4&lt;-c(190.66,185.55,188.53,187.51)
  par(mar=c(2.0,4.5,0.5,2.5))
  plot(x,y4,type="l",xaxt="n",yaxt="n",col="navy",frame=F,lwd=2,
   xlab="levels(ppm)",ylab=expression(bold(paste("HOMA-",beta,"(%)"))),font.lab=2, 
   xlim=c(0,2.5),ylim=c(185,195))
  axis(1,at=c(0,0.5,1.0,1.5,2.0,2.5),lwd=2)
  axis(2,at=c(185,190,195),lwd=2)
  abline(h=190.66,lty=2)
  text(2.0,192, "P for trend&lt;0.01",cex=0.75)
  </code></pre>
  
  <p>How to make beta italic and bold in axis label and P italic and bold in text? Thank you.</p>