Objective: To examine the clinical presentation, diagnostic evaluation, and management of Killian–Jamieson diverticula (KJD) through literature review. Methods: A comprehensive literature review was conducted through December 2018 using keywords Killian–Jamieson diverticula/diverticulum. Data extracted included clinical presentation, imaging characteristics, surgical management, and postoperative care. Sources: PubMed and Google Scholar. Results: Sixty-eight cases of KJD in 59 reports (29M:39F; median 58 years old) were identified for review. The most common presentation was dysphagia (n = 39), suspected thyroid nodule (n = 24) and globus (n = 14). The majority of KJD (n = 51) occur on the left, with rare reports of right side (n = 11) and bilateral (n = 5) presentation. Thirty-two cases describe surgical management: 22 utilizing a transcervical approach, with (n = 13) or without (n = 9) cricopharyngeal myotomy; and 10 reported endoscopic surgery. Diverticula managed transcervically averaged 3.8 cm in size in comparison to average 2.8 cm in the endoscopic group. Time to diet initiation after transcervical surgery averaged 4 days versus 2 days after endoscopic surgery. Complications were reported in 2/68 cases; both were diverticula recurrence after endoscopic surgery. Conclusion: Killian–Jamieson diverticula is a rare diagnosis that should be considered in the evaluation of dysphagia, globus, and also suspected thyroid nodule. When patient symptoms warrant intervention, a transcervical approach, with or without cricopharyngeal myotomy, is most commonly utilized. In recent years, an endoscopic approach has been presented as an alternative for smaller diverticula. Further understanding of the optimal treatment and postoperative management for KJD requires larger cohorts. Level of Evidence: 4

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Purpose To describe our observations of granular corneal dystrophy (GCD) recurrence isolated to the posterior graft-host interface after type 1 big bubble (BB) deep anterior lamellar keratoplasty (DALK). Observations We performed a retrospective chart review of 3 eyes in 2 patients, and literature review to summarize GCD recurrence patterns after DALK. A 29-year-old man with GCD underwent DALK by type 1 BB technique. Three years following surgery, he was found to have recurrence of GCD deposits isolated to the posterior graft-host interface. Similarly, a 53-year-old woman with GCD underwent DALK by BB type 1 technique, and was noted to have trace residual deposits at the posterior graft-host interface that increased in number and size over the course of 6 years. Her fellow eye underwent DALK with type 2 BB formation, without evidence of graft-host interface recurrence over a four year period. Our literature review describes the recurrence patterns of 18 cases of GCD following DALK. Conclusions and importance DALK can be prone to GCD recurrence in the central posterior graft-host interface. Recurrent deposits isolated to the posterior graft-host interface following type 1 BB DALK supports the hypothesis that GCD recurrence may be due to residual pathologic keratocytes in the pre-Descemet layer (PDL).

Tuning the electron-transfer (ET) steps in redox reactions has proven to be an effective strategy to modulate enzyme catalysis. Here, we use 2-oxoacid:ferredoxin oxidoreductase (OFOR) as a model system to study the two-electron reduction of CO 2 and to evaluate the effect of intermolecular ET on catalysis by systematically engineering the reduction potential (E m ) of the electron donor, ferredoxin (Fd), aiming to maximize catalytic CO 2 reduction. Based on the newly determined crystal structure for Fd1 from Hydrogenobacter thermophilus (HtFd1), we expanded the E m of HtFd1 (−485 mV, vs the standard hydrogen electrode) to a range from −440 to −555 mV through changes in the hydrogen bonding network and solvent exposure of the [4Fe− 4S] cluster, with −555 mV being the lowest potential observed for a monocluster [4Fe−4S] Fd. Specifically, replacement of a polar residue (serine) with a non-polar residue (alanine or valine) at the +2 position with respect to the C4 of the C1XXC2XXC3X n C4 [4Fe−4S] cluster-ligating motif abolished an extensive hydrogen bonding network and decreased E m by 40 mV; the introduction of a non-ligating "fifth cysteine" at the +4 position of C4 decreased E m by 60 mV; and increasing the solvent exposure of the [4Fe−4S] cluster by replacement of a bulky residue (leucine) with glycine at the −1 position of C3 increased E m by 45 mV. We constructed an Fd library of 24 Fds with a "potential gradient", ranging from −378 to −555 mV, and evaluated the impact of the Fd potential on OFOR activity. Here, we found that decreasing the Fd potential and therefore providing a larger driving force are beneficial for CO 2 reduction, but only to a point. With the HtFd1_T13I_S64A variant (−515 mV), we were able to achieve a maximum turnover frequency of 81.3 min −1 (or a specific activity of 625 nmol min −1 mg −1 ) in CO 2 reduction.

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