Experimental studies of strong dipolar interparticle interaction in monodisperse Fe3O4 nanoparticles

Interparticle interaction of monodisperse Fe3 O4 nanoparticles has been experimentally investigated by dispersing the nanoparticles in solvents. With increasing the interparticle distances to larger than 100 nm in a controlled manner, the authors found that the blocking temperature (TB) of the nanoparticles drops continuously and eventually gets saturated with a total drop in TB of 7-17 K observed for 3, 5, and 7 nm samples, compared with their respective nanopowder samples. By carefully studying the dependence of TB on the interparticle distance, the authors could demonstrate that the experimental dependence of TB follows the theoretical curve of the dipole-dipole interaction. © 2007 American Institute of Physics.open313

Satellite cell-specific ablation of Cdon impairs integrin activation, FGF signalling, and muscle regeneration

Background: Perturbation in cell adhesion and growth factor signalling in satellite cells results in decreased muscle regenerative capacity. Cdon (also called Cdo) is a component of cell adhesion complexes implicated in myogenic differentiation, but its role in muscle regeneration remains to be determined. Methods: We generated inducible satellite cell-specific Cdon ablation in mice by utilizing a conditional Cdon allele and Pax7 CreERT2. To induce Cdon ablation, mice were intraperitoneally injected with tamoxifen (tmx). Using cardiotoxin-induced muscle injury, the effect of Cdon depletion on satellite cell function was examined by histochemistry, immunostaining, and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay. Isolated myofibers or myoblasts were utilized to determine stem cell function and senescence. To determine pathways related to Cdon deletion, injured muscles were subjected to RNA sequencing analysis. Results: Satellite cell-specific Cdon ablation causes impaired muscle regeneration with fibrosis, likely attributable to decreased proliferation, and senescence, of satellite cells. Cultured Cdon-depleted myofibers exhibited 32 ± 9.6% of EdU-positive satellite cells compared with 58 ± 4.4% satellite cells in control myofibers (P < 0.05). About 32.5 ± 3.7% Cdon-ablated myoblasts were positive for senescence-associated β-galactosidase (SA-β-gal) while only 3.6 ± 0.5% of control satellite cells were positive (P < 0.001). Transcriptome analysis of muscles at post-injury Day 4 revealed alterations in genes related to mitogen-activated protein kinase signalling (P < 8.29 e−5) and extracellular matrix (P < 2.65 e−24). Consistent with this, Cdon-depleted tibialis anterior muscles had reduced phosphorylated extracellular signal-regulated kinase (p-ERK) protein levels and expression of ERK targets, such as Fos (0.23-fold) and Egr1 (0.31-fold), relative to mock-treated control muscles (P < 0.001). Cdon-depleted myoblasts exhibited impaired ERK activation in response to basic fibroblast growth factor. Cdon ablation resulted in decreased and/or mislocalized integrin β1 activation in satellite cells (weak or mislocalized integrin1 in tmx = 38.7 ± 1.9%, mock = 21.5 ± 6%, P < 0.05), previously linked with reduced fibroblast growth factor (FGF) responsiveness in aged satellite cells. In mechanistic studies, Cdon interacted with and regulated cell surface localization of FGFR1 and FGFR4, likely contributing to FGF responsiveness of satellite cells. Satellite cells from a progeria model, Zmpste24−/− myofibers, showed decreased Cdon levels (Cdon-positive cells in Zmpste24−/− = 63.3 ± 11%, wild type = 90 ± 7.7%, P < 0.05) and integrin β1 activation (weak or mislocalized integrin β1 in Zmpste24−/− = 64 ± 6.9%, wild type = 17.4 ± 5.9%, P < 0.01). Conclusions: Cdon deficiency in satellite cells causes impaired proliferation of satellite cells and muscle regeneration via aberrant integrin and FGFR signalling. © 2020 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of Society on Sarcopenia, Cachexia and Wasting Disorders1

Echinostoma ilocanum Infection in Oddar Meanchey Province, Cambodia

Fecal examinations using the Kato Katz technique were performed on a total of 1,287 villagers (945 students and 342 general inhabitants) of Oddar Meanchey Province, Cambodia in May 2007 and November 2009. The overall intestinal helminth egg positive rate was 23.9%, and the most prevalent helminth species was hookworms (21.6%). Other helminth eggs detected included echinostomes (1.0%), Enterobius vermicularis (0.8%), small trematode eggs (0.7%), which may include Opisthorchis viverrini and Haplorchis spp., and Hymenolepis nana (0.4%). In order to recover adult echinostomes, we treated 2 patients with 10-15 mg/kg praziquantel and purged. Total 14 adult echinostomes, 1 and 13 worms from each patient, were collected. The echinostomes characteristically had 49-51 collar spines and 2 round or slightly lobated testes. They were identified as Echinostoma ilocanum (Garrison, 1908) Odhner, 1911. So far as literature are concerned, this is the first record on the discovery of human E. ilocanum infection in Cambodia

Comparative study of the treatment outcomes of osteoporotic compression fractures without neurologic injury using a rigid brace, a soft brace, and no brace : a prospective randomized controlled non-inferiority trial

BACKGROUND:The efficacy of brace application for the treatment of osteoporotic compression fractures remains unclear. The purpose of this study was to compare the treatment outcomes in patients with osteoporotic compression fractures with regard to whether the patients had no braces, rigid braces, or soft braces.METHODS:We randomly assigned sixty patients with acute one-level osteoporotic compression fractures within three days of injury to the no-brace, soft-brace, and rigid-brace groups through 1:1:1 allocation. The primary outcome was the baseline adjusted Oswestry Disability Index score at twelve weeks after compression fracture. The non-inferior margin of the Oswestry Disability Index was set at an average of 10 points.RESULTS:The baseline adjusted Oswestry Disability Index score at twelve weeks after compression fracture in the no-brace group was not inferior to that in the soft-brace or rigid-brace groups. The mean adjusted Oswestry Disability Index score was 35.95 points (95% confidence interval, 25.42 to 46.47 points) in the no-brace group and 37.83 points (95% confidence interval, 26.77 to 48.90 points) in the soft-brace group, with a difference of -1.88 points (95% confidence interval, -7.02 to 9.38 points) between the groups. Similarly, the mean adjusted Oswestry Disability Index score was 35.95 points (95% confidence interval, 25.42 to 46.47 points) in the no-brace group and 33.54 points (95% confidence interval, 23.79 to 43.29 points) in the rigid-brace group, with a difference of 2.41 points (95% confidence interval, -7.86 to 9.27 points) between the groups. During the follow-up assessment period, there was no significant difference among the groups for the overall Oswestry Disability Index scores (p = 0.260), visual analog scale for pain scores for back pain (p = 0.292), and anterior body compression ratios (p = 0.237). However, the Oswestry Disability Index scores and the visual analog scale scores for back pain significantly improved with time after the fractures (p < 0.001), and the body compression ratios significantly decreased with time in all three groups (p < 0.001).CONCLUSIONS:The Oswestry Disability Index scores for the treatment of compression fractures without a brace were not inferior to those with soft or rigid braces. Moreover, the improvement in back pain and progression of anterior body compression were similar among the three groups.OAIID:oai:osos.snu.ac.kr:snu2014-01/102/0000004226/15SEQ:15PERF_CD:SNU2014-01EVAL_ITEM_CD:102USER_ID:0000004226ADJUST_YN:NEMP_ID:A079510DEPT_CD:801CITE_RATE:4.309DEPT_NM:의학과SCOPUS_YN:NCONFIRM:

Prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for non-metastatic right colon cancer (PIONEER study): study protocol of a multicentre single-arm trial

Abstract Background The introduction of complete mesocolic excision (CME) with central vascular ligation (CVL) for right-sided colon cancer has improved the oncologic outcomes. Recently, we have introduced a modified CME (mCME) procedure that keeps the same principles as the originally described CME but with a more tailored approach. Some retrospective studies have reported the favourable oncologic outcomes of laparoscopic mCME for right-sided colon cancer; however, no prospective multicentre study has yet been conducted. Methods This study is a multi-institutional, prospective, single-arm study evaluating the oncologic outcomes of laparoscopic mCME for adenocarcinoma arising from the right side of the colon. A total of 250 patients will be recruited from five tertiary referral centres in South Korea. The primary outcome of this study is 3-year disease-free survival. Secondary outcome measures include 3-year overall survival, incidence of surgical complications, completeness of mCME, and distribution of metastatic lymph nodes. The quality of laparoscopic mCME will be assessed on the basis of photographs of the surgical specimen and the operation field after the completion of lymph node dissection. Discussion This is a prospective multicentre study to evaluate the oncologic outcomes of laparoscopic mCME for right-sided colon cancer. To the best of our knowledge, this will be the first study to prospectively and objectively assess the quality of laparoscopic mCME. The results will provide more evidence about oncologic outcomes with respect to the quality of laparoscopic mCME in right-sided colon cancer. Trial registration ClinicalTrials.gov ID: NCT03992599 (June 20, 2019). The posted information will be updated as needed to reflect protocol amendments and study progress

Effects of warming and eutrophication on coastal phytoplankton production

Phytoplankton production in coastal waters influences seafood production and human health and can lead to harmful algal blooms. Water temperature and eutrophication are critical factors affecting phytoplankton production, although the combined effects of warming and nutrient changes on phytoplankton production in coastal waters are not well understood. To address this, phytoplankton production changes in natural waters were investigated using samples collected over eight months, and under 64 different initial conditions, established by combining four different water temperatures (i.e., ambient T, + 2, + 4, and + 6 degrees C), and two different nutrient conditions (i.e., non-enriched and enriched). Under the non-enriched conditions, the effect of warming on phytoplankton production was significantly positive in some months, significantly negative in others, or had no effect. However, under enriched conditions, warming affected phytoplankton production positively in all months except one, when the salinity was as low as 6.5. These results suggest that nutrient conditions can alter the effects of warming on phytoplankton production. Of several parameters, the ratio of initial nitrate concentration to chlorophyll a concentration [NCCA, mu M (pg L-1)(-1))] was one of the most critical factors determining the directionality of the warming effects. In laboratory experiments, when NCCA in the ambient or nutrient-enriched waters was >= 1.2, warming increased or did not change phytoplankton production with one exception; however, when NCCA was < 1.2, warming did not change or decreased production. In the time series data obtained from the coastal waters of four target countries, when NCCA was 1.5 or more, warming increased phytoplankton production, whereas when NCCA was lower than 1.5, warming lowered phytoplankton production, Thus, it is suggested that NCCA could be used as an index for predicting future phytoplankton production changes in coastal waters.11Ysciescopu

Atomic-scale dynamics of triangular hole growth in monolayer hexagonal boron nitride under electron irradiation

The production of holes by electron beam irradiation in hexagonal boron nitride (hBN), which has a lattice similar to that of graphene, is monitored over time using atomic resolution transmission electron microscopy. The holes appear to be initiated by the formation of a vacancy of boron and grow in a manner that retains an overall triangular shape. The hole growth process involves the formation of single chains of B and N atoms and is accompanied by the ejection of atoms and bundles of atoms along the hole edges, as well as atom migration. These observations are compared to density functional theory calculations and molecular dynamics simulations.open1

Carbonic anhydrase 9 is a predictive marker of survival benefit from lower dose of bevacizumab in patients with previously treated metastatic colorectal cancer

<p>Abstract</p> <p>Background</p> <p>Carbonic anhydrase 9 (CA9) is a marker for hypoxia and acidosis, which is linked to a poor prognosis in human tumors. The purpose of this comparative analysis was to evaluate whether CA9 and VEGF expression are associated with survival outcomes in patients with metastatic colorectal cancer (mCRC) after treatment with bevacizumab as second or later line treatment.</p> <p>Methods</p> <p>Thirty-one mCRC patients who were treated with bevacizumab-containing chemotherapy as second or later line treatment and who had analyzable tumor paraffin blocks were selected for this study. The planned dose of bevacizumab was 5 mg/kg/2-week. Immunohistochemical (IHC) staining of CA9 and VEGF was performed and their expression was scored by the intensity multiplied by percentage of stained area.</p> <p>Results</p> <p>The overall response rate was 19.4% and the disease control rate (DCR) was 61.3% with 6 partial responses and 13 cases of stable disease. The DCR was significantly higher in patients with a lower CA9 expression score compared to those with a higher score (80.0% vs. 27.3%, respectively, P = 0.004). The patients with a low CA9 expression score also showed better outcomes with regard to the median progression-free survival (P = 0.028) and overall survival (P = 0.026). However, VEGF expression was not associated with the DCR and survival.</p> <p>Conclusion</p> <p>Lower degree of CA9 expression was associated with better clinical outcomes in patients with mCRC treated with lower dose bevacizumab-based chemotherapy. Prospective studies are now needed to determine the correlation between CA9 expression and clinical outcomes after bevacizumab treatment, at different doses and in varied settings.</p

Структурные, электрические и люминесцентные характеристики ультрафиолетовых светодиодов, выращенных методом хлорид–гидридной эпитаксии

Electrical and luminescent properties of near−UV light emitting diode structures (LEDs) prepared by hydride vapor phase epitaxy (HVPE) were studied. Variations in photoluminescence and electroluminescence efficiency observed for LEDs grown under nominally similar conditions could be attributed to the difference in the structural quality (dislocation density, density of dislocations agglomerates) of the GaN active layers, to the difference in strain relaxation achieved by growth of AlGaN/AlGaN superlattice and to the presence of current leakage channels in current confining AlGaN layers of the double heterostructure.Изучены электрические и люминесцентные характеристики светодиодных структур (СД), излучающих в ближней ультрафиолетовой (УФ) области и выращенных методом хлорид−гидридной эпитаксии. Обнаружены различия в характеристиках УФ СД, выращенных в номинально одинаковых условиях, которые приписывают различиям в структурном совершенстве (плотности дислокаций и дислокационных агломератов) в активных слоях GaN, разнице в степени релаксации напряжений, достигаемой с помощью сверхрешеток AlGaN/AlGaN, а также существованию каналов токовых утечек в слоях AlGaN, ограничивающих заряд в двойной гетероструктуре.