usb serial port isn't given as an option in the tools menu

I am working on a Mac book pro running sox 10.8 and had previously been able to upload programs to my arduino uno after a break of about an hour today I went back to work and it asked me to select a port when I tried to upload my sketch it did not give me the option for my usb port I checked the usb device tree which wasn't sowing the arduino, since then I have tried everything I can think of to fix the problem including

Ran the "lsof | grep usbmodem" command in the terminal which would just send me to a new line would not give me any response Trying two other usb cables including one brand new one Installed the ftdi drivers Plugged it into a pc which recognized it Reinstalled the arduino environment twice Rebooted several times And the arduino isn't showing up in the usb device tree in the system report. I would appreciate any help ya’ll could give me Thanks