Modified Lothrop procedure in cystic fibrosis patients: does it have a role?

BACKGROUND: The management of frontal sinus disease in cystic fibrosis patients represents a challenge for many surgeons. Procedures can vary from the minimally invasive to those involving extensive open surgery. OBJECTIVE: This study describes the outcomes of the endoscopic modified Lothrop procedure, in terms of safety and morbidity, for cystic fibrosis patients with frontal sinus disease who did not improve following traditional functional endoscopic sinus surgery. METHOD AND RESULTS: The study setting was a tertiary referral unit in a London teaching hospital, the largest national base for adult cystic fibrosis patients. Two patients diagnosed in childhood with cystic fibrosis presented with histories of recurrent, severe frontal sinusitis; both had previously undergone multiple endoscopic sinus surgical procedures. The modified Lothrop procedure was performed on both patients. The outcome measures were symptom resolution and post-operative complications. CONCLUSION: The endoscopic modified Lothrop procedure was beneficial in the cystic fibrosis patients with frontal sinus disease who failed to respond to standard functional endoscopic sinus surgery procedures.

Image-guided, endoscopic removal of migrated titanium dental implants from maxillary sinus: two cases.

OBJECTIVE: We present two cases of dental implant migration into the maxillary sinus, with subsequent removal via image-guided, transnasal endoscopy. METHOD: Presentation of clinical cases, together with a literature review of alternative surgical techniques, the theories behind implant migration, and the benefits of an image-guided, endoscopic approach. RESULTS: One patient was asymptomatic, and the other had begun to experience sinogenic symptoms after implant displacement. Both patients presented to the ENT clinic, and both underwent the BrainLab protocol to generate computed tomography images for navigational reconstruction. Transnasal endoscopy was carried out with this guidance, and the implants were removed successfully in both cases. Previously used surgical techniques such as the Caldwell-Luc procedure or extraction through the tooth socket have higher rates of conversion to open procedures, more damage to the nasal sinuses and higher post-operative complication rates compared with the transnasal endoscopic approach. CONCLUSION: Both patients underwent successful removal of their migrated dental implants with no complications, and neither required any follow-up intervention.

Directed evolution of Tk-subtilisin from a hyperthermophilic archaeon: identification of a single amino acid substitution responsible for low-temperature adaptation.

Tk-subtilisin from the hyperthermophilic archaeon Thermococcus kodakaraensis is synthesized in a prepro-form (prepro-Tk-subtilisin), secreted in a pro-form (pro-Tk-subtilisin), and matured to an active form (mat-Tk-subtilisin*; a Ca(2+)-bound active form of matured domain of Tk-subtilisin) upon autoprocessing and degradation of the propeptide [Tk-propeptide; propeptide of Tk-subtilisin (Gly1-Leu69)]. Pro-Tk-subtilisin exhibited halo-forming activity only at 80 degrees C, but not at 70 and 60 degrees C, because Tk-propeptide is not effectively degraded by mat-Tk-subtilisin* and forms an inactive complex with mat-Tk-subtilisin* at <80 degrees C. Random mutagenesis in the entire prepro-Tk-subtilisin gene, followed by screening for mutant proteins with halo-forming activity at 70 and 60 degrees C, allowed us to identify single Gly56 --> Ser mutation in the propeptide region responsible for low-temperature adaptation of pro-Tk-subtilisin. SDS-PAGE analyses and mat-Tk-subtilisin* activity assay of pro-G56S-subtilisin indicated more rapid maturation than pro-Tk-subtilisin. The resultant active form was indistinguishable from mat-Tk-subtilisin* in activity and stability, indicating that Gly56 --> Ser mutation does not seriously affect the folding of the mature domain. However, this mutation greatly destabilized the propeptide, making it unstructured in an isolated form. As a result, Tk-propeptide with Gly56 --> Ser mutation (G56S-propeptide) was more susceptible to proteolytic degradation and less effectively inhibited mat-Tk-subtilisin* activity than Tk-propeptide. These results suggest that pro-G56S-subtilisin is more effectively matured than pro-Tk-subtilisin at lower temperatures, because autoprocessed G56S-propeptide is unstructured upon dissociation from mat-Tk-subtilisin* and is therefore effectively degraded by mat-Tk-subtilisin*.

[Rapid diagnosis of infection by cytomegalovirus using early-antigen detection (shell vial)]. / Diagnóstico rápido de la infección por citomegalovirus mediante detección de antígeno temprano (shell-vial).

We performed an evaluation of early cytomegalovirus antigen detection (Shell-vial method) for rapid diagnosis of cytomegalovirus infection in patients at risk. A comparative, parallel, prospective study against conventional cell culture in 913 clinical specimens was carried out. Shell-vial technique detected an early cytomegalovirus antigen in culture using an indirect immunofluorescent method with monoclonal antibodies. Cytomegalovirus was detected in 210 specimens (23.0%). In 24 instances (11.4%), cytomegalovirus was only detected by culture, in contrast with 54 specimens (25.7%) that were only positive in Shell-vial (p less than 0.001; McNemar test). Mean detection time for cell culture was 9.2 days, and 16-24 h for the Shell-vial technique. This is a rapid, sensitive, specific and simple to perform method for diagnosis of cytomegalovirus infection. Nevertheless, the predictivity of cytomegalovirus disease was not improved by this technique.