Humic acid induces the endothelial nitric oxide synthase phosphorylation at Ser1177 and Thr495 Via Hsp90α and Hsp90β upregulation in human umbilical vein endothelial cells

Humic acid (HA) has been implicated as a contributory factor for blackfoot disease, which is an endemic peripheral vascular disease. We investigated the effect of HA on the regulation of endothelial nitric oxide (NO) synthase (eNOS) in human umbilical vein endothelial cells (HUVECs) to evaluate the involvement of eNOS and related factors in peripheral vascular impairment with HA exposure. Treatment of HUVECs with HA induced upregulation of eNOS. This result coincides with those of previous studies. Furthermore this is the first study to report that HA induces upregulation of heat shock protein (Hsp)90α, Hsp90β, eNOS phosphorylation at Ser1177, and eNOS phosphorylation at Thr495, as compared to that in the control. In contrast, treatment with BAPTA, an intracellular Ca²⁺ chelator, inhibited upregulation of these proteins induced by HA. This study demonstrates that HA treatment leads to increases in both Hsp90α and Hsp90β proteins and indicates that Hsp90α leads to eNOS phosphorylation at Ser1177 and that Hsp90β leads to eNOS phosphorylation at Thr495, respectively. Upregulation of eNOS, Hsp90α, and Hsp90β in HUVECs is regulated by intracellular Ca²⁺ accumulation induced by HA. These results suggest that upregulation of eNOS phosphorylation at Ser1177 and eNOS phosphorylation at Thr495 produce NO and superoxide anions, respectively, resulting in generation of peroxynitrite, which causes impairment of vascular endothelial cells. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 223–231, 2015.     

Pediatric myositis ossificans mimicking osteosarcoma

Myositis ossificans (MO) is a rare benign cause of heterotopic bone formation in soft tissue that most commonly affects young adults, typically following trauma. We report the case of an 11‐year‐old girl who developed MO mimicking osteosarcoma in her right shoulder. Plain radiography and computed tomography showed poorly defined flocculated densities in the soft tissue and a periosteal reaction along the proximal humerus. On magnetic resonance imaging, the mass displayed an ill‐defined margin and inhomogeneous signal change. Histologically, the mass had a pseudosarcomatous appearance. Based on these findings, the patient was initially misdiagnosed with osteosarcoma at another hospital. The diagnosis was difficult because the patient was 11 years old and had no trauma history, with atypical radiographic changes and a predilection for the site of origin for osteosarcomas. We finally made the correct diagnosis of MO by carefully reviewing and reflecting on the pathological differences between stages.     

Near-infrared spectrometry analysis of fat, neutral sterols, bile acids, and short-chain fatty acids in the feces of patients with pancreatic maldigestion and malabsorption

Summary Conclusion. Near-infrared spectrometry is a new, rapid, and accurate method for measuring fecal fat that does not require a great deal of chemical knowledge and that can be used by anyone. This method is considered indispensable for the diagnosis of pancreatic steatorrhea and treatment follow-up. Methods. Fecal fats (GLC method, van de Kamer method), neutral sterols (GLC method), bile acids (GLC method) and short-chain fatty acids (HPLC method) were assayed by the respective conventional methods in 120 subjects, including patients with pancreatic dysfunction, and the results were compared with the those obtained by near-infrared spectrometry. The correlations between fecal fat excretion measured by the GLC method (x) and van de Kamer method (x) and by near-infrared spectrometry (y) were expressed by y=1.10 x-0.16 (r=0.949, P<0.01) and y=0.750x+1.654 (r=0.930, p<0.01), respectively. Results. The sensitivity and specificity of near-infrared spectrometry for fecal fats were 94.9 and 98.2%, respectively, when compared with the GLC method, and 87.5 and 90.0%, respectively, when compared with the van de Kamer method. In contrast, near-infrared spectrometry was not nearly as accurate as the conventional methods for determining neutral sterols, bile acids, and short-chain fatty acids.     

Angiotensin II stimulation of NAD(P)H oxidase activity: upstream mediators

Angiotensin II (Ang II)-stimulated hypertrophy of vascular smooth muscle cells is mediated by reactive oxygen species (ROS) derived from NAD(P)H oxidases. The upstream signaling mechanisms by which Ang II activates these oxidases are unclear but may include protein kinase C, tyrosine kinases, phosphatidylinositol-3-kinase, and Rac, a small molecular weight G protein. We found that Ang II-stimulated ROS production is biphasic. The first phase occurs rapidly (peak at 30 seconds) and is dependent on protein kinase C activation. The larger second phase of ROS generation (peak at 30 minutes) requires Rac activation, because inhibition of Rac by either Clostridium difficile toxin A or dominant-negative Rac significantly inhibits Ang II-induced ROS production. Phosphatidylinositol-3-kinase inhibitors (wortmannin or LY294002) and the epidermal growth factor (EGF) receptor kinase blocker AG1478 attenuate both Rac activation and ROS generation. The upstream activator of EGF receptor transactivation, c-Src, is also required for ROS generation, because PP1, an Src kinase inhibitor, abrogates the Ang II stimulation of both responses. These results suggest that c-Src, EGF receptor transactivation, phosphatidylinositol-3-kinase, and Rac play important roles in the sustained Ang II-mediated activation of vascular smooth muscle cell NAD(P)H oxidases and provide insight into the integrated signaling mechanisms whereby Ang II stimulation leads to activation of the growth-related NAD(P)H oxidases.     

Impact of mucosal barrier injury laboratory-confirmed bloodstream infection (MBI-LCBI) on central line-associated bloodstream infections (CLABSIs) in department of hematology at single university hospital in Japan

Background

Central line-associated bloodstream infections (CLABSIs) are among the most serious complications especially in blood cancer patients. In January 2013, Centers for Disease and Prevention (CDC) introduced a new surveillance definition of mucosal barrier injury-associated laboratory-confirmed bloodstream infection (MBI-LCBI). This study was to determine the impact of MBI-LCBI on CLABSIs and compare the clinical characteristics of MBI versus non-MBI-LCBI cases.

In vitro neuraminidase inhibitory concentration (IC50) of four neuraminidase inhibitors in the Japanese 2016–17 season: Comparison with the 2010–11 to 2015–16 seasons

To assess the extent of susceptibility to the four most commonly used neuraminidase inhibitors (NAIs) in the viruses epidemic in the 2016–17 Japanese influenza season, we measured the 50% inhibitory concentration (IC₅₀) of these NAIs for influenza virus isolates from patients and compared them with the results from the 2010–11 to 2015–16 seasons.Viral isolation was done with specimens obtained prior to treatment, and the type and subtype was determined by RT-PCR using type- and subtype-specific primers. The IC₅₀ was determined by a neuraminidase inhibition assay using a fluorescent substrate.A total of 276 virus isolates, 6 A (H1N1)pdm09 (2.2%), 249 A (H3N2) (90.2%), and 21 B (7.6%), had the IC₅₀ measured for the four NAIs. B isolates included 11 (52.4%), 9 (42.9%), and one (4.8%) of the Victoria, Yamagata, and undetermined strains, respectively.No A (H1N1)pdm09 with highly reduced sensitivity for oseltamivir was found in the 2016–17 season. No isolate with highly reduced sensitivity to the four NAIs have been found for A (H3N2) or B from the 2010–11 to 2016–17 seasons. No significant trend of increase or decrease was found in the geometric mean IC₅₀s of the four NAIs during the seven studied seasons.These results indicate that the sensitivity to the four commonly used NAIs has been maintained and that any change in the effectiveness of these NAIs would be minute. Common usage of NAIs for patient treatment has not been a driving force in the selection of NAI resistant viruses.     

Cutaneous Mycobacterium chelonae infection following autologous peripheral blood stem cell transplantation for POEMS syndrome

Although hematopoietic stem cell transplantation (HSCT) may increase the curability of refractory hematologic diseases, it requires complication management due to a long-term immunocompromised state. We experienced a case who received an autologous peripheral blood stem cell transplantation (Auto-PBSCT) for POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) and developed cutaneous Mycobacterium chelonae infection. It is clear that attention needs to be paid to prevent bacterial, fungal and viral infection after HSCT. It is also important to keep in mind that tuberculous and nontuberculous mycobacteria (NTM), in rare cases, lead to lethal complications.     

Validation trial for efficacy of ultrasonographic measurement method to predict ascitic volume using virtual ultrasonography

Purpose

The aim of this study was to clarify whether ultrasound quantitative methods were positively correlated with volume of ascites evaluated by whole abdominopelvic CT.

Methods

Sixty-eight patients with cirrhotic ascites were retrospectively analyzed. First, to confirm that virtual ultrasonography (VUS) is an alternative method to conventional ultrasound, 22 patients underwent both conventional ultrasonography and VUS. Second, the efficacy of US quantitative methods (3-point method, 4-point method, 5-point method, and Matsumoto’s method) was confirmed by VUS in 68 patients. We assessed whether the ascites volume predicted by VUS corresponded with that calculated by 3D-CT. Of the 68 patients, 23 patients were analyzed before and after administration of tolvaptan.

Results

The predictive volumes calculated by VUS were remarkably relative to those yielded by conventional US. Correlations between exact volume and those measured by VUS were significantly high (3-point method: r?=?0.882, p?<?0.001; 4-point method: r?=?0.797, p?<?0.001; 5-point method: r?=?0.836, p?<?0.001; Matsumoto’s method: r?=?0.453, p?<?0.001). Correlations between decreasing volume on 3D-CT and that measured by VUS were also significantly high in patients with administration of tolvaptan.

Conclusion

Ascites volume measured by ultrasound was effective, especially the 3-point and 5-point methods. It was useful to assess the efficacy of diuretics in cirrhotic patients.

     

Evaluation of the cell survival curve under radiation exposure based on the kinetics of lesions in relation to dose-delivery time

We have investigated the dose rate effects on cell damage caused by photon-beam irradiation. During a relatively long dose-delivery time with a low dose rate, lesions created in cells may undergo some reactions, such as DNA repair. In order to investigate these reactions quantitatively, we adopted the microdosimetric–kinetic (MK) model and deduced a cell surviving fraction (SF) formula for continuous irradiation. This model enabled us to estimate the SF from dose and dose rate. The parameters in the MK model were determined so as to generate the SF, and we attempted to evaluate the dose rate effects on the SF. To deduce the cell-specific parameters in the SF formula, including the dose rate, we performed a split-dose experiment and a single-dose experiment with a constant dose-delivery time (10 min) (to retain the condition for equivalent behavior of cell lesions) by means of a clonogenic assay. Then, using the MK model parameters, the SFs were reproduced for a variety of dose rates (1.0, 0.31, 0.18, 0.025 and 0.0031 Gy/min) and were compared with reported experimental data. The SF curves predicted by the MK model agreed well with the experimental data, suggesting that the dose rate effects appear in the kinetics of cell lesions during the dose-delivery time. From fitting the analysis of the model formula to the experimental data, it was shown that the MK model could illustrate the characteristics of log-SF in a rectilinear form at a high dose range with a relatively low dose rate.