Kimchi bacteriophages of lactic acid bacteria: population, characteristics, and their role in watery kimchi.

The bacteriophages (phages) in the watery kimchis (Baek-kimchi and Dongchimi) were characterized to determine the phage ecology of lactic acid bacteria (LAB). Kimchi obtained from the Seoul markets had an average of 2.1 log phage particles/mL, corresponding to 28% of the bacterial counts on a log scale. High counts of 5.5-6.5 log particles/mL of phages were noted in the early phase of fermentation (reaching pH 4), and 2.1-3.0 log phage particles/mL were found in the later phase, with some fluctuation in numbers. The LAB hosts changed from Weissella and Leuconostoc to Lactobacillus during Dongchimi fermentation. Fifteen phages, except for those of Lactobacillus, were isolated from diverse strains in the early phase. Five Weissella phages were Podoviridae, and all 10 Leuconostoc phages were Myoviridae. Phages had narrow and different host infection spectra to strains of the same species and high acidic stability. Therefore, the mortality and diversity of LAB during natural kimchi fermentation may be related to the specific phages of the hosts. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00930-y.

Follow-up with computed tomography after spontaneous isolated dissection of the splanchnic artery.

The aim of this study was to evaluate radiological changes after spontaneous isolated dissection of the superior mesenteric artery (SIDSMA) and spontaneous isolated dissection of the celiac artery (SIDCA) using computed tomography (CT). This single-center retrospective study was approved by the hospital institutional review board. We reviewed the medical records and morphological CT findings of 33 consecutive patients with SIDSMA or SIDCA who were diagnosed between January 2001 and February 2016. We analyzed changes on follow-up CT images including length of the dissection, presence of a thrombus in the false lumen, maximal outer diameter, degree of luminal stenosis, patency of distal flow, and end-organ injury. We classified short-term (within the first week) and long-term (between the first week and sixth month) follow-up groups and analyzed differences in radiological changes over time using Wilcoxon signed-rank tests (continuous variables) and Fisher exact probability tests (categorical variables). Additionally, we examined patients who completed follow-up CT within 3 days after symptomatic changes. Comparing initial and final CT findings, a majority of patients with SIDSMA and SIDCA showed no significant changes in most CT parameters, including dissection length, thrombus presence, dissection diameter, stenosis degree, and extended distal branch. Between the short-term and long-term CT follow-up groups, there were no significant differences in radiological changes except for in the degree of luminal stenosis at the dissected segment in SIDSMA (P = 0.043). Only 10 patients completed follow-up CT within 3 days after symptomatic changes (progression or regression); of these, 1 patient had radiological findings that matched symptom progression, showing an increase in the degree of luminal stenosis and end-organ injury. There was no splanchnic artery dissection-related mortality, symptom progression, or event recurrence. In conclusion, CT follow-up of SIDSMA and SIDCA was mainly useful in the acute phase of dissection, with no significant radiological changes occurring in the long term. Accordingly, we question the utility of long-term follow-up CT after spontaneous isolated arterial dissection, especially in the absence of symptom progression.

Differentiating primary hepatic angiosarcomas from hemangiomatosis and epithelioid hemangioendotheliomas using gadoxetic acid-enhanced and diffusion-weighted MR imaging.

OBJECTIVES: To assess the value of gadoxetic acid-enhanced and diffusion-weighted (DW) magnetic resonance (MR) imaging for differentiating primary hepatic angiosarcomas from hemangiomatosis and epithelioid hemangioendotheliomas (EHEs). METHODS: We reviewed MR images of seven patients with pathologically determined hepatic angiosarcomas, 11 patients with hemangiomatosis, and five patients with EHEs. Two radiologists assessed morphologic features, signal intensity (SI), enhancement patterns, and the presence of diffusion restriction by consensus and compared between angiosarcoma vs hemangiomatosis and angiosarcoma vs EHEs. RESULTS: Angiosarcomas more frequently showed mixed well- and ill-defined margins (6, 85.7%), mixed strong and intermediate-high SI (5, 71.4%) on T2-weighted images, mixed peripheral and/or central nodular and rim and/or target enhancement (5, 71.4%), and mixed presence and absence of diffusion restriction (7, 100%) compared with hemangiomatosis and EHEs (P < 0.05). The overall survival rate in patients with angiosarcomas was 42.9% at 3 months and 14.3% at 14 months, whereas all patients with EHEs were alive during the follow-up period from 4 to 43 months (P = 0.002). CONCLUSION: Gadoxetic acid-enhanced and DW MR imaging may help differentiate primary hepatic angiosarcomas with hemangioma-like appearance, EHE-like appearance, or both; and poor prognosis from hemangiomatosis and EHEs.

Self-assembled and highly selective sensors based on air-bridge-structured nanowire junction arrays.

We describe a strategy for creating an air-bridge-structured nanowire junction array platform that capable of reliably discriminating between three gases (hydrogen, carbon monoxide, and nitrogen dioxide) in air. Alternatively driven dual nanowire species of ZnO and CuO with the average diameter of ∼30 nm on a single substrate are used and decorated with metallic nanoparticles to form two-dimensional microarray, which do not need to consider the post fabrications. Each individual nanowires in the array form n-n, p-p, and p-n junctions at the micro/nanoscale on single substrate and the junctions act as electrical conducting path for carriers. The adsorption of gas molecules to the surface changes the potential barrier height formed at the junctions and the carrier transport inside the straight semiconductors, which provide the ability of a given sensor array to differentiate among the junctions. The sensors were tested for their ability to distinguish three gases (H2, CO, and NO2), which they were able to do unequivocally when the data was classified using linear discriminant analysis.