What is the effect of a changed plea of not guilty to all charges in a criminal case?

After a jury had been empanelled and testimony started, appellant changed his plea of not guilty to all the charges in the six-count information filed against him to one of no contest to three of those counts and their respective charged enhancements. He was, pursuant to the negotiated plea bargain, sentenced to a total of 25 years in state prison. Appellant filed a timely notice of appeal and an application for the issuance of a certificate of probable cause. The trial court denied the application for a certificate of probable cause. Appellant then filed a brief pursuant to People v. Wende (1979) 25 Cal.3d 436 asking this court to review the record in the court below and determine if there are any issues deserving of further briefing and then review by us. We have done so, but found no such issues and hence affirm the judgment of the superior court.