Association of depression and smoking cessation: outcomes of an 18-year retrospective cohort study.

BACKGROUND: Depression is frequently associated with unsuccessful smoking cessation. OBJECTIVE: In this study, we investigated the impact of depression history on smoking cessation success in a clinical setting. METHODS: This retrospective study included 726 patients who visited our smoking cessation clinic between January 1, 2001, and December 31, 2018. Kaplan-Meier analyses and Cox proportional hazards regression models were used to perform univariate and multivariate analyses of smoking cessation success factors. RESULTS: Among the 726 patients, 76 had a history of depression and demonstrated significantly lower 12-week quit rate compared to those without (33.6% vs. 69.6%, p < .001). Multivariate Cox analysis revealed a significant association between abstinence rate and history of depression (hazard ratio 2.251, 95% CI 1.505-3.315, p < .001), history of schizophrenia (hazard ratio 2.716, 95% CI 1.427-4.840, p = .003), and Fagerström Nicotine Dependence Test scores (hazard ratio 1.519, 95% CI 1.053-2.197, p = .025). CONCLUSIONS: Our findings suggested that a history of depression is a significant prognostic factor for smoking cessation, underscoring the need for targeted interventions for patients with a history of depression. The findings of this study are subject to potential selection bias due to recruitment from a single hospital, which may limit the generalizability of our results. This study highlights the necessity for novel, specialized smoking cessation therapies to support patients with a history of depression in their cessation journey.

Corynebacterium kroppenstedtii in granulomatous mastitis: Analysis of formalin-fixed, paraffin-embedded biopsy specimens by immunostaining using low-specificity bacterial antisera and real-time polymerase chain reaction.

Granulomatous mastitis (GM) is a rare inflammatory disease of the post-lactation breast, clinically mimicking breast cancer. GM is microscopically characterized by formation of epithelioid granulomas and abscess (suppurative granulomas) with lipid droplet-centered inflammation. Corynebacterium kroppenstedtii (Ck) is known as a causative bacterium of GM, and identification of Ck infection within the lesion should thus be essential for confirming the diagnosis. In the present study, we analyzed formalin-fixed, paraffin-embedded (FFPE) biopsy specimens of a total of 18 GM lesions with immunostaining and real-time PCR for Ck genome. Widely cross-reactive rabbit antisera against Bacillus Calmette-Guerin (BCG), Bacillus cereus, Treponema pallidum and Escherichia coli were chosen. With real-time PCR, Ck genome was demonstrated in 7 of 18 GM lesions. Immunohistochemically, the low-specificity antisera reacted with the cytoplasm of phagocytes and/or granuloma-engulfed lipid droplets in 12 of 18 GM lesions. Antigenic positivity was observed in the following order: BCG > B. cereus > T. pallidum > E. coli. Real-time PCR using DNA extracted from FFPE sections was useful but not consistent for identifying the Ck genome in GM, while immunostaining using cross-reactive antisera against four kinds of bacteria was not Ck-specific but was applicable to visualizing bacterial infection within the GM lesions.

Regulation of pH attenuates toxicity of a byproduct produced by an ethanologenic strain of Sphingomonas sp. A1 during ethanol fermentation from alginate.

Marine macroalgae is a promising carbon source that contains alginate and mannitol as major carbohydrates. A bioengineered ethanologenic strain of the bacterium Sphingomonas sp. A1 can produce ethanol from alginate, but not mannitol, whereas the yeast Saccharomyces paradoxus NBRC 0259-3 can produce ethanol from mannitol, but not alginate. Thus, one practical approach for converting both alginate and mannitol into ethanol would involve two-step fermentation, in which the ethanologenic bacterium initially converts alginate into ethanol, and then the yeast produces ethanol from mannitol. In this study, we found that, during fermentation from alginate, the ethanologenic bacterium lost viability and secreted toxic byproducts into the medium. These toxic byproducts inhibited bacterial growth and killed bacterial cells and also inhibited growth of S. paradoxus NBRC 0259-3. We discovered that adjusting the pH of the culture supernatant or the culture medium containing the toxic byproducts to 6.0 attenuated the toxicity toward both bacteria and yeast, and also extended the period of viability of the bacterium. Although continuous adjustment of pH to 6.0 failed to improve the ethanol productivity of this ethanologenic bacterium, this pH adjustment worked very well in the two-step fermentation due to the attenuation of toxicity toward S. paradoxus NBRC 0259-3. These findings provide information critical for establishment of a practical system for ethanol production from brown macroalgae.

Bacterial pyruvate production from alginate, a promising carbon source from marine brown macroalgae.

Marine brown macroalgae is a promising source of material for biorefining, and alginate is one of the major components of brown algae. Despite the huge potential availability of alginate, no system has been reported for the production of valuable compounds other than ethanol from alginate, hindering its further utilization. Here we report that a bacterium, Sphingomonas sp. strain A1, produces pyruvate from alginate and secretes it into the medium. High aeration and deletion of the gene for d-lactate dehydrogenase are critical for the production of high concentrations of pyruvate. Pyruvate concentration and productivity were at their maxima (4.56 g/l and 95.0 mg/l/h, respectively) in the presence of 5% (w/v) initial alginate, whereas pyruvate produced per alginate consumed and % of theoretical yield (0.19 g/g and 18.6%, respectively) were at their maxima at 4% (w/v) initial alginate. Concentration of pyruvate decreased after it reached its maximum after cultivations for 2 or 3 days at 145 strokes per minute. Our study is the first report to demonstrate the production of other valuable compounds than ethanol from alginate, a promising marine macroalgae carbon source.