Reduced metallic artefacts in 3 T knee MRI using fast spin-echo multi-point Dixon compared to fast spin-echo T2-weighted sequences

AIM

To compare multi-point Dixon magnetic resonance imaging (MRI) and fast spin-echo (FSE) T2-weighted imaging (WI) with regard to the size of metallic artefacts when imaging the knee joint.

MATERIALS AND METHODS

A total of 42 patients who underwent anterior cruciate ligament (ACL) reconstruction and follow-up imaging with 3 T MRI using the multi-point Dixon technique was included in this retrospective study. The maximal distance of the image distortion area around the metallic artefact was measured (interference screw of femoral tunnel area) on sagittal images of both FSE T2WI (T2WI and fat-suppressed [FS] T2WI) and multi-point Dixon (water only image and in-phase image) sequences. The maximal distance of the image distortion were compared using paired t-tests across the image sequences (multi-point Dixon water only image versus FS T2WI and multi-point Dixon in-phase image versus T2WI).

RESULTS

The mean distance of the image distortion from metallic artefacts regardless of the image sequence ranged from 16.6 mm to 24.5 mm (Table 2). The mean distances measured by two readers on multi-point Dixon (water only image) sequences were significantly shorter than those in FS T2WI sequences (p<0.001). In contrast, the mean distances measured by two readers on multi-point Dixon (in-phase image) sequences did not differ from those of T2WI (p>0.05) sequences.

CONCLUSION

The water-only image of multi-point Dixon technique reduces the amount of metallic artefacts compared to that in FS FSE T2WI sequences; however, the metallic artefacts were not significantly different between in-phase images of multi-point Dixon and FSE T2WI.

Prognostic impact of the length of the longitudinal resection margin in colon cancer

AIM

Although several guidelines recommend a longitudinal resection margin (LRM) of at least 5 cm, the impact of the LRM on survival is still unknown. The study assessed the prognostic significance of the LRM in patients with colon cancer.

METHOD

We retrospectively reviewed 1343 primary colon cancer patients without distant metastasis who underwent curative resection between January 2004 and December 2012. Patients were classified into three groups: LRM < 3 cm (n = 186), LRM ≥ 3 and <5 cm (n = 376) and LRM ≥5 cm (n = 781). Clinicopathological characteristics and the oncological outcome in the three groups were compared.

RESULTS

The median LRM length was 5.0 cm (range 0.5-26.0 cm). With increasing LRM, the number of retrieved lymph nodes (LNs) tended to increase (19.5 ± 12.0, 22.1 ± 12.8 and 30.0 ± 16.2; P < 0.001). After a median follow-up period of 45 (1-128) months, 3-year disease-free survival (DFS) (89.2%, 89.0% and 87.0%; P = 0.629) and 5-year overall survival (OS) (89.0%, 92.1% and 91.8%; P = 0.679) were not significantly different between the three groups. When confounders were adjusted, LRM was not significantly associated with either DFS or OS, but the number of retrieved LNs (< 12) was an independent risk factor for both DFS (hazard ratio 1.748, 95% confidence interval 1.048-2.917) and OS (hazard ratio 1.929, 95% confidence interval 1.046-3.559).

CONCLUSION

LRM was not associated with oncological outcome, but care should be taken to obtain an adequate number of LNs for better survival.

A CASE OF ADRENAL MYELOLIPOMA A PATIENT WITH BREAST CANCER

Background

Adrenal myelolipoma is a rare benign tumor composed of adipose tissue and hematopoetic elements resembling bone marrow. The majority of myelolipoma do not produce adrenal hormones and are only found as a result of evaluation for another disorder. With the widespread use of non-invasive abdominal imaging for various reason, its incidental detection has become more common. There are a few cases of breast cancer with concomitant adrenal myelolipoma in the literature.

Case

A 43-year-old woman presented to endocrine clinic due to presurgical assessment of adrenal mass prior breast cancer surgery. Abdominal CT showed a 9 x 8 cm sized, lobulated contour heterogeneous fatty density mass with peripheral calcification in right adrenal gland. Hormonal studies for adrenal incidentaloma revealed: Aldosterone/Renin ratio, 0.70 ([normal range < 30]; normal DHEA-S, 85.0 µg/dL ([normal range, 80 -560 µg/dL]), ACTH 25 pg/mL ([normal range, 10 - 60 pg/mL]), morning serum cortisol 8.9 µg/dL ([normal range, 5 - 12 µg/dL]). In 24-hour urine, there revealed free cortisol 21.6 µg/day ([normal range, 10 - 50 µg/day); metanephrine 0.19 mg/day ([normal range < 0.8 mg/day]); 17-ketosteroid 14.06 mg/day ([normal range, 7 - 20 mg/day]). The hormonal results of adrenal mass revealed as nonfunctioning. The adrenal mass was surgically resected in order to rule out malignancy. Pathology report showed myelolipoma.

Conclusion

We reported a case of adrenal myelolipoma coexisting with breast cancer where the diagnosis was made incidentally based on radiological features, treated with surgical resection.

Protective Effect of Polydeoxyribonucleotide Against Renal Ischemia-Reperfusion Injury in Mice

BACKGROUND

Polydeoxyribonucleotide (PDRN) is an A2A receptor agonist that induces vascular endothelial growth factor (VEGF) production during the pathological condition of low tissue perfusion. Ischemia-reperfusion injury (IRI) is a major problem after renal transplantation. In the present study, we investigated whether PDRN exhibits reno-protective effects against ischemia-reperfusion-induced acute kidney injury in mice.

METHODS

Renal ischemia-reperfusion injury was induced in male C57BL/6 mice by bilateral renal pedicle occlusion for 30 minutes, followed by reperfusion for 48 hours. PDRN (8 mg/kg body weight intraperitoneally) was administered 30 minutes before IRI.

RESULTS

Treatment with PDRN significantly decreased neutrophil gelatinase-associated lipocalin levels in the urine, blood urea nitrogen level, and serum creatinine levels as well as kidney tubular injury. Western blotting showed that PDRN significantly increased the levels of vascular endothelial growth factor and B-cell lymphoma protein and attenuated p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, inducible nitric oxide synthase, and Bcl-2-associated X protein levels 48 hours after IRI.

CONCLUSIONS

Our findings suggest that PDRN is a potential therapeutic agent for acute ischemia-induced renal damage.

Protective Effect of Eupatilin Pretreatment Against Hepatic Ischemia-Reperfusion Injury in Mice

BACKGROUND

Eupatilin, a pharmacologically active flavone derived from Artemisia species, is known to have antioxidant and antiinflammatory activities. Ischemia-reperfusion injury (IRI) is a major critical event that commonly occurs after liver transplantation and resection. Furthermore, inflammatory responses to IRI exacerbate the resultant hepatic injury. In this study, we investigated whether eupatilin protects against IR-induced acute liver injury in mice.

MATERIALS AND METHODS

Partial (70%) hepatic IRI was induced in male C57BL/6 mice by portal triad pedicle occlusion for 90 minutes followed by reperfusion for 6 hours. Eupatilin (10 mg/kg body weight, oral) was administered 4 days before the IRI.

RESULTS

Treatment with eupatilin significantly decreased serum alanine aminotransferase and serum aspartate aminotransferase as well as liver histologic changes. Eupatilin also prevented hepatic glutathione depletion and increased malondialdehyde levels induced by IRI. Western blotting indicated that eupatilin significantly increased the levels of heat shock protein and B-cell lymphoma 2 protein, attenuated inducible nitric oxide synthase, and cleaved caspase-3 levels 6 hours after IRI. The expression of the Toll-like receptor 2/4, and phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor was significantly decreased in the eupatilin pretreatment group.

CONCLUSIONS

Eupatilin improved the acute hepatic IRI by reducing inflammation and apoptosis. These findings suggest that eupatilin is a promising therapeutic agent against acute IR-induced hepatic damage.

Red Ginseng Administration Before Islet Isolation Attenuates Apoptosis and Improves Islet Function and Transplant Outcome in a Syngeneic Mouse Marginal Islet Mass Model

BACKGROUND

Transplantation of isolated islets is a promising treatment for diabetes. Red ginseng (RG) is steamed ginseng and has been reported to enhance insulin secretion-stimulating and anti-apoptotic activities in pancreatic β-cells. In this study, we examined the hypothesis that pre-operative RG treatment enhances islet cell function and anti-apoptosis and investigated whether RG improves islet engraftment by transplant of a marginal mass of syngeneic islets pretreated with RG in diabetic mice.

METHODS

Balb/c mice were randomly divided into 2 groups, and 1 group was administered RG (400 mg/kg/day orally) for 7 days before islet isolation. In vitro islet viability and function were assessed. After cytokine treatment, cell viability, function, and apoptosis of islet cells were analyzed. Furthermore, we studied the effects of RG in a syngeneic islet graft model. A marginal mass of syngeneic mouse islets was transplanted into diabetic hosts.

RESULTS

Islet pretreatment with RG showed 1.4-fold higher glucose-induced insulin secretion than did control islets. RG pretreatment upregulated B-cell lymphoma 2 (Bcl-2) expression and downregulated Bcl-associated X protein (BAX), caspase-3, and inducible nitric oxide synthase (iNOS) expression. Glucose-induced insulin release, NO, and apoptosis were significantly improved in RG-pretreated islets compared with cytokine-treated islets. RG-pretreated mice exhibited improved marginal mass islet graft survival compared with controls.

CONCLUSIONS

These results suggest that pre-operative RG administration enhanced islet function before transplantation and attenuated cytokine-induced damage associated with apoptosis. These studies indicate that inhibition of apoptosis by RG significantly improved islet cell and graft function after isolation and transplantation, respectively.

Multilayering of Calcium Aerosol-OT at the Mica/Water Interface Studied with Neutron Reflection: Formation of a Condensed Lamellar Phase at the CMC

Using specular neutron reflection, the adsorption of sodium and calcium salts of the surfactant bis(2-ethylhexyl) sulfosuccinate (Aerosol-OT or AOT) has been studied at the mica/water interface at concentrations between 0.1 and 2 CMC. The pH dependence of the adsorption was also probed. No evidence of the adsorption of Na(AOT) was found even at the critical micelle concentration (CMC) while the calcium salt was found to adsorb significantly at concentrations of 0.5 CMC and above. This interesting and somewhat unexpected finding demonstrates that counterion identity may be used to tune the adsorption of anionic surfactants on anionic surfaces. At the CMC, three condensed bilayers of Ca(AOT)₂ were adsorbed at pH 7 and 9 and four bilayers adsorbed at pH 4. Multilayering at the CMC of Ca(AOT)₂ on the mica surface is an unusual feature of this surfactant/surface combination. Only single bilayer adsorption has been observed at other surfaces at the CMC. We suggest this arises from the high charge density of mica which must provide an excellent template for the surfactant.

Two different phase-change origins with chemical- and structural-phase-changes in C doped (1.5 wt.%) In3Sb1Te2

We fabricated C-doped (1.5 wt.%) In₃Sb₁Te₂ (CIST) thin films with amorphous phase (a-CIST) using a sputter method. Two electrical-phase-changes at 250 and 275 °C were observed in the sheet resistance measurement. In order to understand the origin of these electrical-phase-changes, all samples were characterized by XRD, TEM, and HRXPS with synchrotron radiation. In a-CIST, only weak Sb-C bonding was observed. In the first electrical-phase-change at 250 °C, strong Sb-C bonding occurred without an accompanying structural/phase change (still amorphous). On the other hand, the second electrical-phase-change at 275 °C was due to the structural/phase change from amorphous to crystalline without a chemical state change.

Assessing the suitability of a non-lethal biopsy punch for sampling fish muscle tissue

Samples for the analysis of stable isotopes, genetics and other tissue sampling methods of small fish are often taken via lethal techniques. The aim of this study was to determine the suitability of a non-lethal sampling method for removing muscle tissue from fish under 30 cm total length (TL). A 4-mm biopsy punch was used to remove muscle tissue from two different species, Lutjanus russelli (Lutjanidae) and Lethrinus laticaudis (Lethrinidae). Several scales were removed from the sampling location, and then the biopsy punch was inserted to remove the muscle tissue. Immediately following this, a mixture of Fish Bandage™ and three drops of Betadine™ antiseptic solution was applied to the wound to reduce the chance of infection. The biopsy punch removes an average of 8 mg of muscle tissue from the fish, more than is required for stable isotope and genetic analyses (1 mg). The condition of fish subjected to our three treatments, biopsied fish, a handling controls and a tank control, was compared via gill beat counts at the time of biopsy and 3, 6, 9, 12 and 24 h after treatment. Overall, no instances of mortality were recorded across the study for all species and all treatments. This method has been found to be a suitable non-lethal method in the removal of muscle tissue from these two fish species, potentially also other species under 30 cm TL, by eliminating mortality and minimising stress responses in sampled fishes.

Preventive behaviors by the level of perceived infection sensitivity during the Korea outbreak of Middle East Respiratory Syndrome in 2015

OBJECTIVES

This study was performed to investigate the relationship between community residents’ infection sensitivity and their levels of preventive behaviors during the 2015 Middle East Respiratory Syndrome (MERS) outbreak in Korea.

METHODS

Seven thousands two hundreds eighty one participants from nine areas in Gyeonggi-do including Pyeongtaek, the origin of the outbreak in 2015 agreed to participate in the survey and the data from 6,739 participants were included in the final analysis. The data on the perceived infection sensitivity were subjected to cluster analysis. The levels of stress, reliability/practice of preventive behaviors, hand washing practice and policy credibility during the outbreak period were analyzed for each cluster.

RESULTS

Cluster analysis of infection sensitivity due to the MERS outbreak resulted in classification of participants into four groups: the non-sensitive group (14.5%), social concern group (17.4%), neutral group (29.1%), and overall sensitive group (39.0%). A logistic regression analysis found that the overall sensitive group with high sensitivity had higher stress levels (17.80; 95% confidence interval [CI], 13.77 to 23.00), higher reliability on preventive behaviors (5.81; 95% CI, 4.84 to 6.98), higher practice of preventive behaviors (4.53; 95% CI, 3.83 to 5.37) and higher practice of hand washing (2.71; 95% CI, 2.13 to 3.43) during the outbreak period, compared to the non-sensitive group.

CONCLUSIONS

Infection sensitivity of community residents during the MERS outbreak correlated with gender, age, occupation, and health behaviors. When there is an outbreak in the community, there is need to maintain a certain level of sensitivity while reducing excessive stress, as well as promote the practice of preventive behaviors among local residents. In particular, target groups need to be notified and policies need to be established with a consideration of the socio-demographic characteristics of the community.

3D isotropic T2-weighted fast spin echo (VISTA) versus 2D T2-weighted fast spin echo in evaluation of the calcaneofibular ligament in the oblique coronal plane

AIM

To investigate whether the image quality of three-dimensional (3D) volume isotropic fast spin echo acquisition (VISTA) magnetic resonance imaging (MRI) of the calcaneofibular ligament (CFL) view is comparable to that of 2D fast spin echo T2-weighted images (2D T2 FSE) for the evaluation of the CFL, and whether 3D VISTA can replace 2D T2 FSE for the evaluation of CFL injuries.

MATERIALS AND METHODS

This retrospective study included 76 patients who underwent ankle MRI with CFL views of both 2D T2 FSE MRI and 3D VISTA. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of both techniques were measured. The anatomical identification score and diagnostic performances were evaluated by two readers independently. The diagnostic performances of 3D VISTA and 2D T2 FSE were analysed by sensitivity, specificity, and accuracy for diagnosing CFL injury with reference standards of surgically or clinically confirmed diagnoses. Surgical correlation was performed in 29% of the patients, and clinical examination was used in those who did not have surgery (71%).

RESULTS

The SNRs and CNRs of 3D VISTA were significantly higher than those of 2D T2 FSE. The anatomical identification scores on 3D VISTA were inferior to those on 2D T2 FSE, and the differences were statistically significant (p<0.05). There were no significant differences in diagnostic performance between the two sequences when diagnoses were classified as normal or abnormal.

CONCLUSION

Although the image quality of 3D VISTA MRI of the CFL view is not equal to that of 2D T2 FSE for the anatomical evaluation of CFL, 3D VISTA has a diagnostic performance comparable to that of 2D T2 FSE for the diagnosis of CFL injuries.

Multiplexed and spatiotemporal measurements of glutamate secreted by neurons and bacteria

By applying an in vivo biotinylation platform, glutamate-sensing protein can be easily immobilized on streptavidin-functionalized magnetic microbeads, which expands the detection modality for the spatiotemporal measurements of glutamate secreted by adherent neuronal cells and suspension microbial cells using fluorescence microscopy and microplate photometers.

The association between perceived unmet medical need and mental health among the Republic of Korea Armed Forces

INTRODUCTION

We investigated the effect of unmet medical need on the mental health of Republic of Korea (ROK) Armed Forces personnel, as most of the service members work in remote areas and often experience such unmet needs.

METHODS

This study used secondary data from the 2014 Military Health Survey (MHS), conducted by the ROK School of Military Medicine and designed to collect military health determinants. Descriptive statistics showed the general characteristics of the study populations by variable. We specifically compared the population after stratifying participants by suicide ideation. An analysis of variance was also carried out to compare Kessler Psychological Distress Scale 10 Scores. Additionally, dependent spouses and children of both active-duty service members and retirees are included among those entitled to Military Health System healthcare.

RESULTS

Among the 4967 military personnel, 681 (13.7%) individuals reported an experience of unmet medical need within the past 12 months and gave reasons of 'no time (5.15%)', 'long office wait (2.6%)', 'no money (0.22%)', 'long distance from base (1.19%)', 'illness but not very serious (1.65%)', 'mistrust in doctors (1.95%)' and 'pressure due to performance appraisal (0.95%)'. Regression analysis revealed that unmet medical need was significantly associated with negative mental health (β=1.753, p<0.0001) and increased suicide ideation (OR=2.649, 95% CI 1.84 to 3.82). Also, soldiers reporting unmet medical need due to 'no money', 'no time' or 'pressure due to performance appraisal' were significantly more likely to experience similar negative mental health effects.

CONCLUSIONS

Our study indicates that unmet medical need is significantly associated with soldiers' mental health decline and suicide ideation, highlighting the importance of providing military personnel with timely, affordable and sufficient medical care.

From blue to black: Anthropogenic forcing of carbon and nitrogen influx to mangrove-lined estuaries in the South China Sea

Southeast Asia is the global centre of mangrove development but human activities have dramatically reduced mangrove area in the region. An analysis is made of the shift in carbon and nitrogen influxes into the South China Sea (SCS) resulting from three anthropogenic nutrient sources: domestic sewage discharge, fertilizer use in rice agriculture and environmental loss from mariculture, between 1997 and 2010. Anthropogenic C and N influxes were, respectively, 1.81× and 1.43× those in 1997, with coastal aquaculture contributing most to the increase. In contrast, fringing mangroves provided ~44% of the C but only ~3% of the N from anthropogenic sources in 2010. In 1997, influx from mangroves was 113% and 6% of anthropogenic influx for C and N, respectively. This dominance by relatively labile anthropogenic nutrients over mangrove sources would change nearshore trophodynamics, with negative implications for the resilience of mangroves and nutrient-intolerant systems such as corals.

Protein stability changes of the novel p.Arg180Cys mutant A glycosyltransferase resulted in a weak A phenotype

A novel A subgroup allele (c.538C>T p.Arg180Cys) showing weak A phenotype was found in a 30-year-old Korean woman with ABO discrepancy. Using 3D structural analysis, protein stability prediction and flow cytometric analysis of ABO antigen expression on HeLa cells transfected with plasmids containing the p.Arg180Cys mutant, we found that the Arg180 residue in the loop region of the A glycosyltransferases (GTA) structure plays significant role in stabilizing its closed conformation, which is required for substrate binding and catalysis study.

Low Adherence to Immunosuppressants Is Associated With Symptom Experience Among Kidney Transplant Recipients

PURPOSE

The purpose of this study was to investigate the relationship between immunosuppressant-related symptom experience (SE) and adherence to immunosuppressant regimens among kidney transplant (KT) recipients.

METHODS

A total of 239 KT recipients on an immunosuppressant regimen who were followed up after transplantation participated in this study. Data was collected through a self-reported questionnaire survey (medication adherence, SE, and quality of life) and medical record review.

RESULTS

Low adherence in the immunosuppressant group was associated with longer time since KT, less comorbidity (<3), and a higher rehospitalization rate. Low adherence among KT recipients showed significantly greater overall symptom occurrence (P = .001) and symptom distress (P = .002) levels than patients with high or medium adherence after adjusting for a number of covariates. The most common symptom both in terms of occurrence (96.4%) and distress (91.1%) among poorly adherent KT recipients was tiredness.

CONCLUSION

Low adherence to an immunosuppressant regimen was significantly associated with high SE among KT recipients. Strategies to decrease immunosuppressant-related SE are needed to improve adherence to immunosuppressants.

Evaluation report on the causal association between humidifier disinfectants and lung injury

OBJECTIVES

As of November 2011, the Korean government recalled and banned humidifier disinfectants (HDs) from the market, because four case-control studies and one retrospective epidemiological study proved the association between HDs and lung injury of unknown cause. The report reviewed the causal role of HDs in lung injury based on scientific evidences.

METHODS

A careful examination on the association between the HDs and lung injury was based on the criteria of causality inference by Hill and the US Surgeon General Expert Committee.

RESULTS

We found that all the evidences on the causality fulfilled the criteria (strength of association, consistency, specificity, temporality, biologic gradient, plausibility, coherence, experiment, analogy, consideration of alternative explanations, and cessation of exposure), which proved the unknown cause lung injury reported in 2011 was caused by the HDs. In particular, there was no single reported case of lung injury since the ban in selling HDs in November 2011 as well as before the HDs were sold in markets.

CONCLUSIONS

Although only a few epidemiological studies in Korea have evaluated the association between lung injury and the use of HDs, those studies contributed to proving the strong association between the use of the HDs and lung injury, based on scientific evidence.

Allele-specific duplex polymerase chain reaction to differentiate Mycobacterium abscessus subspecies and to detect highly clarithromycin-resistant isolates

On the basis of the structural differences of erm, we used a duplex polymerase chain reaction (PCR) to differentiate Mycobacterium abscessus subsp. abscessus and subsp. massiliense isolates and to detect the point mutations of 23S rRNA gene that confer a high level of resistance to clarithromycin. Subsp. massiliense strains occupying almost half of the clinical isolates can be simply identified, and their clarithromycin susceptibility can be rapidly determined.