Uncharacterized Bacterial Structures Revealed by Electron Cryotomography.

Electron cryotomography (ECT) can reveal the native structure and arrangement of macromolecular complexes inside intact cells. This technique has greatly advanced our understanding of the ultrastructure of bacterial cells. We now view bacteria as structurally complex assemblies of macromolecular machines rather than as undifferentiated bags of enzymes. To date, our group has applied ECT to nearly 90 different bacterial species, collecting more than 15,000 cryotomograms. In addition to known structures, we have observed, to our knowledge, several uncharacterized features in these tomograms. Some are completely novel structures; others expand the features or species range of known structure types. Here, we present a survey of these uncharacterized bacterial structures in the hopes of accelerating their identification and study, and furthering our understanding of the structural complexity of bacterial cells.IMPORTANCE Bacteria are more structurally complex than is commonly appreciated. Here we present a survey of previously uncharacterized structures that we observed in bacterial cells by electron cryotomography, structures that will initiate new lines of research investigating their identities and roles.

Intraocular pressure and visual field damage as risk factors for visual field progression in filtering surgery.

BACKGROUND AND OBJECTIVE: To evaluate the relationship between preoperative visual field severity and postoperative intraocular pressure as risk factors for visual field progression. PATIENTS AND METHODS: Patients undergoing trabeculectomy (TRAB, n = 92 eyes of 73 patients) or combined trabeculectomy and cataract extraction by phacoemulsification (COMBO, n = 49 eyes of 41 patients) by one surgeon with at least 6 months of follow-up were reviewed. RESULTS: Both the COMBO and TRAB treatment groups experienced a substantial decrease in mean intraocular pressure (4.7 +/- 6.0 and 10.1 +/- 6.5 mm Hg) and mean number of ocular hypotensive medications (1.8 +/- 1.2 and 2.2 +/- 1.5), respectively. In the subset of 47 eyes with reliable visual fields, the COMBO group experienced a mean improvement in mean deviation of 2.75 dB, and the TRAB group experienced only minimal changes in visual fields. CONCLUSION: In general, visual fields did not worsen following trabeculectomy or combined surgery.

Twelve-month, randomized, controlled trial of bimatoprost 0.01%, 0.0125%, and 0.03% in patients with glaucoma or ocular hypertension.

PURPOSE: To evaluate the intraocular pressure (IOP)-lowering efficacy and safety of ophthalmic formulations of bimatoprost 0.01% and 0.0125% compared with bimatoprost 0.03%. DESIGN: Prospective, randomized, double-masked, multicenter clinical trial. METHODS: Patients with glaucoma or ocular hypertension were randomized to receive once-daily bimatoprost 0.01% (n = 186), bimatoprost 0.0125% (n = 188), or bimatoprost 0.03% (n = 187) for 12 months. The primary efficacy measure was IOP. Safety measures included adverse events and an objective assessment of conjunctival hyperemia. RESULTS: Baseline mean IOPs were similar among treatment groups. Differences in mean IOP between the bimatoprost 0.01% or 0.0125% groups and the bimatoprost 0.03% group were less than 0.9 mm Hg throughout follow-up. Bimatoprost 0.01%, but not bimatoprost 0.0125%, was equivalent in efficacy to bimatoprost 0.03% based on predetermined criteria (limits of the 95% confidence interval of the between-group difference in mean IOP within +/- 1.5 mm Hg at all time points and within +/- 1 mm Hg at most time points). The overall incidence of treatment-related adverse events was reduced significantly in the bimatoprost 0.01% and bimatoprost 0.0125% groups compared with the bimatoprost 0.03% group (P < or = .034). The percentage of patients with a moderate to severe increase from the baseline macroscopic hyperemia score was: bimatoprost 0.01%, 3.2%; bimatoprost 0.0125%, 9.0%; bimatoprost 0.03%, 9.1% (P = .019 for bimatoprost 0.01% vs 0.03%). CONCLUSIONS: Bimatoprost 0.01% was equivalent to bimatoprost 0.03% in lowering IOP throughout 12 months of treatment and demonstrated improved tolerability, including less frequent and severe conjunctival hyperemia. Bimatoprost 0.01% demonstrated a better benefit-to-risk ratio than bimatoprost 0.0125%.

Two-year double-masked comparison of bimatoprost with timolol in patients with glaucoma or ocular hypertension.

The object of this study was to compare the long term efficacy and safety of bimatoprost with timolol in patients with glaucoma or ocular hypertension. In a 12-month extension of two identically designed 1-year, multicenter, randomized, double-masked clinical trials, patients were treated topically with bimatoprost 0.03% QD (n=167), bimatoprost 0.03% BID (n=131), or timolol 0.5% BID (n=81). Main outcome measures were IOP at 8 am and 10 am and safety parameters. Bimatoprost QD provided significantly greater mean reduction from baseline IOP than did timolol at both measurements at each study visit (P< or =.001). At 10 am (peak timolol effect) at month 24, the mean reduction from baseline IOP was 7.8 mm Hg with bimatoprost QD and 4.6 mm Hg with timolol (P<.001). Patients treated with bimatoprost QD also sustained significantly lower mean IOP than timolol-treated patients at every follow-up visit throughout the 2-year study period (P< or =.006). At 10 am at month 24, a significantly greater proportion of bimatoprost QD than timolol patients achieved target pressures of < or =13-18 mm Hg (P< or =.010). Bimatoprost sustained an excellent safety profile during the second year of treatment. Most adverse events were mild, and there were no reports of increased iris pigmentation, uveitis, or CME. The incidence of hyperemia was significantly higher with bimatoprost QD (13.8%) than with timolol (2.5%) (P=.006). Mean reduction from baseline IOP with bimatoprost BID was not significantly different from that with timolol at month 24 at 10 am (P=.474). We conclude that bimatoprost QD provides superior IOP lowering to timolol, and is safe and well tolerated over 24 months of treatment.

Evolving paradigms in the medical treatment of glaucoma.

In the last 5 years, numerous novel ocular hypotensive agents have been introduced for the control of intraocular pressure (IOP). Clinicians now have more options than ever in medical therapy for the treatment of glaucoma and ocular hypertension. When selecting an ocular hypotensive medication for their patients, clinicians should consider not only the IOP-lowering efficacy of an agent but also the ability of the drug to achieve target levels of IOP that are low enough to stop the progression of glaucomatous damage. Other considerations should include how well the drug controls diurnal IOP, the likelihood of serious adverse events, the versatility of the medication for use as an adjunctive agent, as well as other potential attributes (e.g., neuroprotection).

Non-surgical post perforation repair with mineral trioxide aggregate: a case report.

Mineral trioxide aggregate, or MTA, is a biocompatible material that has demonstrated numerous clinical applications in endodontics. It appears to be an improvement over other materials for use in procedures that involve root repair and bone healing, as it has consistently demonstrated the ability to promote regeneration of the original tissues when it is placed in contact with the periradicular tissues. This article describes the use of MTA for the successful non-surgical repair of an iatrogenic post perforation.

Personal view:

KIE: From his perspective as a physician and as the son of an elderly, mentally incapacitated nursing home patient, the author discusses his conflicting feelings about active, voluntary euthanasia. He weighs the relief of suffering and the maintenance of dignity against religious beliefs that condemn suicide and euthanasia, the criminal status of euthanasia in Britain, and the difficulty of providing adequate safeguards against its misuse. Cohen concludes that it may be safer to combine a complete prohibition on ending life with improved care that maintains the dignity of the chronically ill and provides all reasonable relief of pain and suffering.^ieng