Background and Aims Probe-based confocal laser endomicroscopy (pCLE) and volumetric laser endomicroscopy (VLE) (also known as frequency domain optical coherence tomography) are advanced endoscopic imaging modalities that may be useful in the diagnosis of dysplasia associated with Barrett’s esophagus (BE). We performed pCLE examination in ex-vivo EMR specimens and compared the diagnostic performance of using the current VLE scoring index (previously established as OCT-SI) and a novel VLE diagnostic algorithm (VLE-DA) for the detection of dysplasia. Methods A total of 27 patients with BE enrolled in a surveillance program at a tertiary-care center underwent 50 clinically indicated EMRs that were imaged with VLE and pCLE and classified into neoplastic (N = 34; high-grade dysplasia, intramucosal adenocarcinoma) and nonneoplastic (N = 16; low-grade dysplasia, nondysplastic BE), based on histology. Image datasets (VLE, N = 50; pCLE, N = 50) were rated by 3 gastroenterologists trained in the established diagnostic criteria for each imaging modality as well as a new diagnostic algorithm for VLE derived from a training set that demonstrated association of specific VLE features with neoplasia. Sensitivity, specificity, and diagnostic accuracy were assessed for each imaging modality and diagnostic criteria. Results The sensitivity, specificity, and diagnostic accuracy of pCLE for detection of BE dysplasia was 76% (95% confidence interval [CI], 59–88), 79% (95% CI, 53–92), and 77% (95% CI, 72–82), respectively. The optimal diagnostic performance of OCT-SI showed a sensitivity of 70% (95% CI, 52–84), specificity of 60% (95% CI, 36–79), and diagnostic accuracy of 67%; (95% CI, 58–78). The use of the novel VLE-DA showed a sensitivity of 86% (95% CI, 69–96), specificity of 88% (95% CI, 60–99), and diagnostic accuracy of 87% (95% CI, 86–88). The diagnostic accuracy of using the new VLE-DA criteria was significantly superior to the current OCT-SI (P < .01). Conclusion The use of a new VLE-DA showed enhanced diagnostic performance for detecting BE dysplasia ex vivo compared with the current OCT-SI. Further validation of this algorithm in vivo is warranted.

Methyl-coenzyme M reductase (MCR) is the key enzyme of methanogenesis and anaerobic methane oxidation. The activity of MCR is dependent on the unique nickel-containing tetrapyrrole known as coenzyme F430. We used comparative genomics to identify the coenzyme F430 biosynthesis (cfb) genes and characterized the encoded enzymes from Methanosarcina acetivorans C2A. The pathway involves nickelochelation by a nickel-specific chelatase, followed by amidation to form Ni-sirohydrochlorin a,c-diamide. Next, a primitive homolog of nitrogenase mediates a six-electron reduction and γ-lactamization reaction before a Mur ligase homolog forms the six-membered carbocyclic ring in the final step of the pathway. These data show that coenzyme F430 can be synthesized from sirohydrochlorin using Cfb enzymes produced heterologously in a nonmethanogen host and identify several targets for inhibitors of biological methane formation.

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Herbal medications are being increasingly used by the American population especially for common conditions like arthritis. They have been reported to cause adverse effects, including significant hepatotoxicity, but reporting remains sporadic. We report here a patient who developed drug induced liver injury following the intake of Move Free, which is an over-the-counter arthritis supplement. We propose that Chinese skullcap, which is one of the herbal ingredients of the medication, is responsible for the adverse event. There was a strong temporal association between the intake of supplement and onset of symptoms, and also there have been a few recent case reports implicating the same component. A unique observation in our case is the occurrence of pulmonary infiltrates simultaneously with the hepatotoxicity, and this side effect has not been well documented before. Both the hepatic and pulmonary complications completely resolved over few weeks after the patient stopped taking the medication. Since these supplements are readily available over the counter, we feel that it is important to document possible adverse outcomes to raise awareness in the medical community and also among patients.