Associated factors with surgical site infections after hepatectomy: Predictions and countermeasures by a retrospective cohort study

Background: To clarify the factors associated with post-hepatectomy surgical site infections (SSIs), the clinicopathological data of 526 patients who underwent hepatectomy was retrospectively examined as a retrospectively cohort study. Methods: Patient demographics, liver functions, histological findings, surgical records and post-hepatectomy morbidity were compared between non-SSI and SSI groups; the SSI group included superficial and deep SSIs. Results: The prevalence of SSIs (5-8%) has not changed over an 18-year period. Deep SSIs were significantly more increased in male patients with lower performance statuses and American Society of Anesthesiologists (ASA) scores (p < 0.05). SSIs tended to be less prevalent, although not significant (p = 0.10), in patients who underwent laparoscopic hepatectomies compared to those who underwent laparotomies. For patients in whom hemostatic devices were used, the prevalence of superficial SSIs was significantly lower than those in whom the devices were not used (p < 0.05). Blood loss and transfusion were significantly more frequent in the deep SSI group compared to other groups (p < 0.01). Hospital stay in the deep SSI group was significantly longer compared to other groups. The incidence of morbidity was more frequent in the SSI groups compared with the non-SSI group (p < 0.001). A multivariate analysis showed that not using a vessel sealing device was significantly associated with superficial SSIs; male gender, hepatic failure and bile leakage were significantly associated with deep SSIs (p < 0.05). Conclusions: SSIs were important indicators of patient outcomes after hepatectomies, and preventing SSI development after surgical procedures is an important step in improving the overall prevalence of SSIs

Sonazoid-enhanced intraoperative ultrasonography in patients with gall bladder diseases: A preliminary study

Background:Ultrasonography using Sonazoid, a novel contrast agent containing microbubbles, is a useful diagnostic modality for intrahepatic mass lesions with specific characteristics in two phases: contrast enhancement of early vascular perfusion and perfusion defect of the lesion in the late phase. To improve the diagnostic accuracy of intraoperative ultrasonography (IOUS) in biliary neoplasms, particularly gall bladder, we investigated the usefulness of the Sonazoid contrast agent in a preliminary study.Subjects and Methods:We examined IOUS images of 23 patients with gall bladder disease. Sonazoid was administered intravenously, and early arterial and venous phase images of the tumor were obtained during laparotomy.Results:Tumors included the localized type of adenomyomatosis in the fundus of the gallbladder (GAM) in seven patients as benign controls, adenomatous diseases in three, and gallbladder carcinoma (GC) in 13. Sonazoid IOUS scanning was performed in all patients, with no adverse effects. Although GC showed high enhancement in 77% of the tumors, GAM and adenoma also showed mild enhancement in more than half of them. Pseudo-positivity was observed in one case of hyperplastic polyps, and pseudo-negativity was observed in two patients. Cholesterol polyps and a suspicious lesion of liver metastasis by the computed tomography were not enhanced with Sonazoid treatment.Conclusion:Although there remains a problem of pseud-positivity in the intracystic lesions, Sonazoid IOUS may be a useful tool to detect vascularity and its location or extension of gallbladder diseases; however, neither significance of differential diagnosis with benign diseases nor other clinical significance was found

Increased In Vitro Intercellular Barrier Function of Lung Epithelial Cells Using Adipose-Derived Mesenchymal Stem/Stromal Cells

With the emergence of coronavirus disease-2019, researchers have gained interest in the therapeutic efficacy of mesenchymal stem/stromal cells (MSCs) in acute respiratory distress syndrome; however, the mechanisms of the therapeutic effects of MSCs are unclear. We have previously reported that adipose-derived MSCs (AD-MSCs) strengthen the barrier function of the pulmonary vessels in scaffold-based bioengineered rat lungs. In this study, we evaluated whether AD-MSCs could enhance the intercellular barrier function of lung epithelial cells in vitro using a transwell coculture system. Transepithelial electrical resistance (TEER) measurements revealed that the peak TEER value was significantly higher in the AD-MSC coculture group than in the AD-MSC non-coculture group. Similarly, the permeability coefficient was significantly decreased in the AD-MSC coculture group compared to that in the AD-MSC non-coculture group. Immunostaining of insert membranes showed that zonula occuldens-1 expression was significantly high at cell junctions in the AD-MSC coculture group. Moreover, cell junction-related gene profiling showed that the expression of some claudin genes, including claudin-4, was upregulated in the AD-MSC coculture group. Taken together, these results showed that AD-MSCs enhanced the barrier function between lung epithelial cells, suggesting that both direct adhesion and indirect paracrine effects strengthened the barrier function of lung alveolar epithelium in vitro

Visualization of acetylcholine distribution in central nervous system tissue sections by tandem imaging mass spectrometry

Metabolite distribution imaging via imaging mass spectrometry (IMS) is an increasingly utilized tool in the field of neurochemistry. As most previous IMS studies analyzed the relative abundances of larger metabolite species, it is important to expand its application to smaller molecules, such as neurotransmitters. This study aimed to develop an IMS application to visualize neurotransmitter distribution in central nervous system tissue sections. Here, we raise two technical problems that must be resolved to achieve neurotransmitter imaging: (1) the lower concentrations of bioactive molecules, compared with those of membrane lipids, require higher sensitivity and/or signal-to-noise (S/N) ratios in signal detection, and (2) the molecular turnover of the neurotransmitters is rapid; thus, tissue preparation procedures should be performed carefully to minimize postmortem changes. We first evaluated intrinsic sensitivity and matrix interference using Matrix Assisted Laser Desorption/Ionization (MALDI) mass spectrometry (MS) to detect six neurotransmitters and chose acetylcholine (ACh) as a model for study. Next, we examined both single MS imaging and MS/MS imaging for ACh and found that via an ion transition from m/z 146 to m/z 87 in MS/MS imaging, ACh could be visualized with a high S/N ratio. Furthermore, we found that in situ freezing method of brain samples improved IMS data quality in terms of the number of effective pixels and the image contrast (i.e., the sensitivity and dynamic range). Therefore, by addressing the aforementioned problems, we demonstrated the tissue distribution of ACh, the most suitable molecular specimen for positive ion detection by IMS, to reveal its localization in central nervous system tissues