Surveillance of the Middle East respiratory syndrome (MERS) coronavirus (CoV) infection in healthcare workers after contact with confirmed MERS patients: incidence and risk factors of MERS-CoV seropositivity

Given the mode of transmission of Middle East respiratory syndrome (MERS), healthcare workers (HCWs) in contact with MERS patients are expected to be at risk of MERS infections. We evaluated the prevalence of MERS coronavirus (CoV) immunoglobulin (Ig) G in HCWs exposed to MERS patients and calculated the incidence of MERS-affected cases in HCWs. We enrolled HCWs from hospitals where confirmed MERS patients had visited. Serum was collected 4 to 6 weeks after the last contact with a confirmed MERS patient. We performed an enzyme-linked immunosorbent assay (ELISA) to screen for the presence of MERS-CoV IgG and an indirect immunofluorescence test (IIFT) to confirm MERS-CoV IgG. We used a questionnaire to collect information regarding the exposure. We calculated the incidence of MERS-affected cases by dividing the sum of PCR-confirmed and serology-confirmed cases by the number of exposed HCWs in participating hospitals. In total, 1169 HCWs in 31 hospitals had contact with 114 MERS patients, and among the HCWs, 15 were PCR-confirmed MERS cases in study hospitals. Serologic analysis was performed for 737 participants. ELISA was positive in five participants and borderline for seven. IIFT was positive for two (0.3%) of these 12 participants. Among the participants who did not use appropriate personal protective equipment (PPE), seropositivity was 0.7% (2/294) compared to 0% (0/443) in cases with appropriate PPE use. The incidence of MERS infection in HCWs was 1.5% (17/1169). The seroprevalence of MERS-CoV IgG among HCWs was higher among participants who did not use appropriate PPE.

Evaluation of Circulating Markers of Neutrophil Extracellular Trap (NET) Formation as Risk Factors for Diabetic Retinopathy in a Case-Control Association Study

Background: Inflammatory stimuli can induce neutrophils to release nuclear DNA combined with histones into the extracellular space, forming neutrophil extracellular traps. Because inflammation contributes to diabetic retinopathy, it is plausible that neutrophil extracellular trap formation actively occurs in diabetic retinopathy. This case-control study investigated the clinical relevance of circulating levels of neutrophil extracellular trap components as risk factors of diabetic retinopathy, and further evaluated whether glucose induced neutrophil extracellular trap formation in vitro using whole blood from healthy volunteers. Methods: Circulating levels of DNA-histone complexes, cell free double-stranded DNA, and polymorphonuclear neutrophil elastase, considered to be markers of neutrophil extracellular trap formation, were measured in patients with diabetic retinopathy (n=28) and without (n=62) and in 28 healthy controls. Results: Circulating DNA-histone complex and polymorphonuclear neutrophil elastase levels were significantly increased in patients with diabetic retinopathy compared with those without retinopathy. Multivariable logistic regression analysis, adjusted for glycated hemoglobin levels and fasting blood glucose, revealed that DNA-histone complex and polymorphonuclear neutrophil elastase levels were significant independent risk factors of retinopathy. In vitro experiments also showed that glucose significantly increased markers of neutrophil extracellular trap formation in a dose-dependent manner. Conclusions: Markers of neutrophil extracellular trap formation were independent risk factors of diabetic retinopathy. This finding provides a new insight into the potential therapeutic and preventive approaches to dampen neutrophil extracellular trap formation.

Patiromer: A Review in Hyperkalaemia

Patiromer (Veltassa(™)) for oral suspension is a sodium-free potassium binder that is approved in the USA for the treatment of hyperkalaemia. In clinical trials, patiromer significantly reduced serum potassium levels from baseline to week 4 in patients with chronic kidney disease (CKD) and mild to severe hyperkalaemia (OPAL-HK), or CKD, mild to moderate hyperkalaemia and type 2 diabetes mellitus (AMETHYST-DN), who were receiving renin-angiotensin-aldosterone system inhibitors (RAASis; drugs that inhibit the renal excretion of potassium). Among patients in OPAL-HK who had moderate to severe hyperkalaemia at baseline and normokalaemia on patiromer and RAASis at week 4, continuing patiromer for a further 8 weeks maintained reductions in potassium levels more effectively than switching to placebo (i.e. withdrawing patiromer); consequently, fewer patiromer than placebo recipients experienced recurrent hyperkalaemia during this period. Furthermore, almost all patiromer (vs. less than half of placebo) recipients were still receiving RAASi therapy at the end of this trial. In AMETHYST-DN, the significant reduction from baseline in serum potassium levels seen at week 4 was sustained for up to 52 weeks. Patiromer was generally well tolerated in these trials, with no treatment-related serious adverse events or deaths. Commonly occurring treatment-related adverse events include mild to moderate constipation and hypomagnesaemia, and there is a low risk of hypokalaemia. In conclusion, oral patiromer is a useful new option for patients with hyperkalaemia.

Expression of autotaxin and lysophosphatidic acid receptors 1 and 3 in the developing rat lung and in response to hyperoxia

We sought to evaluate lysophosphatidic acid (LPA) signaling improvement in lung development by assessing the expression of autotaxin and LPA receptor 1 and 3 (LPAR1 and LPAR3) in the neonatal rat lung during normal perinatal development and in response to hyperoxia. In the developmental study, rats were sacrificed on days 17, 19, and 21 of gestation; on postnatal days 1, 4, and 7; and at adulthood (postnatal 9 weeks). In the hyperoxia study, 42 postnatal 4-day-old rat pups were divided into seven groups and exposed to either 85% O2 for 24, 72, or 120 h or room air for 0, 24, 72, or 120 h. The rats were then euthanized after 0, 24, 72, and 120 h of exposure. Immunofluorescence demonstrated that autotaxin, LPAR1, and LPAR3 proteins were broadly colocalized in airway epithelial cells, but mainly distributed in vascular endothelial and mesenchymal cells during the first postnatal week. The expression of autotaxin, LPAR1, and LPAR3 were increased during late gestation and then decreased after birth. Autotaxin expression and enzymatic activity were significantly increased at 72 and 120 h after exposure to hyperoxia. LPAR1 and LPAR3 expression was also increased after 120 h of hyperoxic exposure. These findings suggest that LPA-associated molecules were upregulated at birth and induced by hyperoxia in the developing rat lung. Therefore, the LPA pathway may be involved in normal lung development, including vascular development, as well as wound-healing processes of injured neonatal lung tissue, which is at risk of neonatal hyperoxic acute lung injury.

The MDM2 small-molecule inhibitor RG7388 leads to potent tumor inhibition in p53 wild-type neuroblastoma

Neuroblastoma is an aggressive pediatric malignancy which is >98% p53 wild-type at diagnosis. As a primary repressor of p53 activity and part of a p53-activated negative feedback loop, targeting of mouse double minute 2 homolog (MDM2) is an attractive therapeutic approach to reactivation of p53. Since development of the first selective MDM2 inhibitor, Nutlin-3a, newer compounds have been developed for increased potency and improved bioavailability. Herein, we sought to determine the efficacy and specificity of a second-generation MDM2 inhibitor, RG7388, in neuroblastoma cell lines and xenografts and examine its effect on the p53-independent pathway of hypoxia-inducible factor-1 alpha (HIF-1α)/vascular endothelial growth factor (VEGF). Cell viability and apoptosis studies were performed on the neuroblastoma cell lines, NGP, SH-SY5Y, LAN-5, LAN-5 si-p53 (p53 silenced), and SK-N-AS (p53 null). RG7388 potently decreased cell proliferation and activated p53-dependent apoptosis. Tumor-bearing mice treated with RG7388 demonstrated significant tumor inhibition by 59% in NGP (P=0.003), 67% in SH-SY5Y (P=0.006), and 75% in LAN-5 (P=0.0019) p53 wild-type xenograft tumors, but no inhibitory effect on LAN-5 si-p53 or SK-N-AS p53-silenced/null xenograft tumors. Moreover, RG7388 was found to inhibit the p53-independent pathway of HIF-1α/VEGF with decreased gene expression and alteration of angiogenesis. Our study supports the further evaluation of RG7388 as a novel treatment option in p53 wild-type neuroblastoma at diagnosis and relapse.

High normal albuminuria is associated with arterial stiffness and carotid atherosclerosis in Korean patients with type 2 diabetes

BACKGROUND AND AIMS

Current evidence suggests that high normal albuminuria is significantly associated with increased cardiovascular risk. This study investigated the association between urine albumin-to-creatinine ratio (ACR) within the normal range and subclinical atherosclerosis in Korean patients with type 2 diabetes.

METHODS AND RESULTS

This cross-sectional study involved 521 type 2 diabetic patients with normoalbuminuria. Brachial-ankle pulse wave velocity (baPWV) measurement and ultrasound assessment of carotid atherosclerosis was done. Subclinical atherosclerosis was assessed by the presence of high baPWV (>1682 cm/s), carotid atherosclerosis (intima-media thickness >0.8 mm or the presence of plaques), and carotid stenosis (≥50% of luminal narrowing). Across the tertiles of ACR, there was a trend for an increasing prevalence of high baPWV (16.8%, 20.0%, and 38.2%, P < 0.001), carotid atherosclerosis (46.9%, 55.4%, and 64.7%, P < 0.001), and carotid stenosis (12.7%, 16.0%, and 30.1%, P < 0.001). In multivariate analysis, patients in the highest ACR tertile had an odds ratio of 2.05 (95% confidence interval [CI], 1.13-3.72, P = 0.019) for high baPWV, 1.78 (95% CI, 1.08-2.93, P = 0.024) for carotid atherosclerosis, and 2.72 (95% CI, 1.44-5.11, P = 0.002) for carotid stenosis compared to those in the lowest tertile. The relation of ACR with carotid atherosclerosis and stenosis remained significant even in patients without diabetic retinopathy.

CONCLUSION

High normal albuminuria was significantly associated with atherosclerotic vascular changes, independent of retinopathy and other cardiovascular risk factors. High normal albuminuria may be an early marker for subclinical atherosclerosis in type 2 diabetes.

Clinical significance of serum bilirubin and gamma-glutamyltransferase levels on coronary atherosclerosis assessed by multidetector computed tomography

BACKGROUND AND AIMS

Low bilirubin and high gamma-glutamyltransferase (GGT), which are endogenous markers of oxidative stress, confer a higher risk of cardiovascular disease (CVD). We investigated associations between serum concentrations of bilirubin, GGT and coronary atherosclerosis.

METHODS AND RESULTS

A cross-sectional analysis was performed on 1520 subjects who underwent multidetector computed tomography scans. Coronary atherosclerosis was assessed by coronary artery calcium score (CACS) and obstructive coronary artery disease (OCAD), was defined as the presence of coronary artery stenosis of ≥50%. Total bilirubin (TB) level was negatively correlated with CACS and coronary stenosis whereas GGT level was positively correlated with CACS in men. However, there was no correlation between TB, GGT levels and either CACS or coronary artery stenosis in women. In a multivariate-adjusted model, TB level was inversely associated with a CACS > 100 [odds ratio (OR) per log standard deviation (SD), 0.67; 95% confidence interval (CI), 0.52-0.87], and OCAD (OR per log SD, 0.77; 95% CI, 0.62-0.95) in men. By contrast, GGT level was positively associated with a CACS > 100 (OR per log SD, 1.35; 95% CI, 1.05-1.73) but not with OCAD. Adding TB and GGT to the conventional risk factors increased predictive accuracy for CACS > 100 (net reclassification improvement index [NRI] = 13.1%, P = 0.026; integrated discrimination index [IDI] = 0.024, P = 0.001) and for OCAD (NRI = 12.6%, P = 0.026; IDI = 0.010, P = 0.013).

CONCLUSIONS

Low TB and high GGT levels were concomitantly associated with coronary atherosclerosis in Korean men. Future studies are needed to elucidate the causal associations of TB and GGT with CVD.

Analysis of aberrantly spliced transcripts of a novel de novo GNAS mutant in a male with albright hereditary osteodystrophy and PHP1A

Pseudohypoparathyroidism (PHP) is a genetic disorder due to target-organ unresponsiveness to parathyroid hormone (PTH). PHP type 1A (PHP1A) is an autosomal dominant disease characterized by Albright hereditary osteodystrophy (AHO) and PTH resistance caused by defects at the GNAS locus. We analyzed the GNAS gene in a male with typical AHO and elevated PTH levels. We identified a novel de novo heterozygous mutation at the splice donor site in intron-7 (IVS7+1G>A, c.585+1G>A) of the GNAS gene. No GNAS mutations were detected in his parents. Our patient was diagnosed with PHP1A due to a heterozygous de novo mutation in the GNAS gene. Reverse transcriptase (RT) PCR analysis and sequencing revealed that this de novo splice mutation generated alternative splicing errors leading to the formation of 2 mutant transcripts: one with exon-7 deleted, the other with whole intron-7 included. To investigate whether these aberrantly spliced transcripts were stable, we assessed the differential expression of GNAS mRNAs in the proband's blood by real-time quantitative RT-PCR. In the proband, the relative expression levels of wild-type, exon-7-deleted, and intron-7-included GNAS mRNAs were 0.21, 6.12E-07, and 1.08E-04, respectively, relative to wild-type GNAS mRNA from a healthy control (set at 1.0). This suggests that this novel de novo splicing mutation generates rapidly decaying mutant transcripts, which might affect stimulatory G-protein activity and give rise to this sporadic case. In conclusion, this is an interesting report of aberrantly spliced mRNAs from a de novo splice mutation of the GNAS gene causing PHP1A in a male.

Which tissues are best for microbiological diagnosis in patients with pyogenic vertebral osteomyelitis undergoing needle biopsy?

Identification of the causative microorganism is important in the management of pyogenic vertebral osteomyelitis (PVO). The aim of this study was to investigate whether culture positive rates differ between needle biopsy sites in patients with PVO, and which tissues are best for microbiological diagnosis. Between January 2005 and December 2013, we conducted a retrospective cohort study of PVO patients who had soft-tissue abscesses (paraspinal or psoas abscesses) and who received needle biopsy for microbiological diagnosis. Needle biopsy sites were classified into two anatomical categories: vertebral bodies, or soft tissues (intervertebral discs, paraspinal abscesses, or psoas abscesses). A generalized estimating equation model was developed to identify factors associated with tissue-culture positivity. During the study period a total of 136 tissues were obtained by needle biopsy from 128 PVO patients with soft-tissue abscesses. The culture positive rates of vertebral bodies and soft tissues were 39.7% (29/73), and 63.5% (40/63), respectively (p < 0.05). In a multivariate analysis, male gender (adjusted odds ratio (aOR) 2.24, 95% CI 1.00-5.02), higher C-reactive protein (aOR 1.07, 95% CI 1.01-1.15), positive blood culture (aOR 2.57, 95% CI 1.01-6.59), and soft tissues as biopsy site compared with vertebral bodies (aOR 2.28, 95% CI 1.08-4.78) were independent factors associated with tissue culture positivity. Soft tissues were the best sites for microbiological diagnosis in PVO patients undergoing needle biopsy.

A reusable robust radio frequency biosensor using microwave resonator by integrated passive device technology for quantitative detection of glucose level

A reusable robust radio frequency (RF) biosensor with a rectangular meandered line (RML) resonator on a gallium arsenide substrate by integrated passive device (IPD) technology was designed, fabricated and tested to enable the real-time identification of the glucose level in human serum. The air-bridge structure fabricated by an IPD technology was applied to the RML resonator to improve its sensitivity by increasing the magnitude of the return loss (S21). The resonance behaviour, based on S21 characteristics of the biosensor, was analysed at 9.20 GHz with human serum containing different glucose concentration ranging from 148-268 mg dl(-1), 105-225 mg dl(-1) and at a deionised (D) water glucose concentration in the range of 25- 500 mg dl(-1) for seven different samples. A calibration analysis was performed for the human serum from two different subjects and for D-glucose at a response time of 60 s; the reproducibility, the minimum shift in resonance frequency and the long-term stability of the signal were investigated. The feature characteristics based on the resonance concept after the use of serum as an analyte are modelled as an inductor, capacitor and resistor. The findings support the development of resonance-based sensing with an excellent sensitivity of 1.08 MHz per 1 mg dl(-1), a detection limit of 8.01 mg dl(-1), and a limit of quantisation of 24.30 mg dl(-1).

Prevalence of blaZ gene types and the cefazolin inoculum effect among methicillin-susceptible Staphylococcus aureus blood isolates and their association with multilocus sequence types and clinical outcome

Cefazolin treatment failures have been described for bacteraemia caused by methicillin-susceptible Staphylococcus aureus (MSSA) with type A β-lactamase and inoculum effect (InE). We investigated the prevalence of blaZ (β-lactamase) gene types and a cefazolin InE among MSSA blood isolates in South Korea and evaluated their association with specific genotypes. The clinical impact of the cefazolin InE was also evaluated. A total of 220 MSSA isolates were collected from a prospective cohort study of S. aureus bacteraemia. A pronounced InE with cefazolin was defined as a ≥4-fold increase in the minimum inhibitory concentration (MIC) between a standard and high inoculum, resulting in a non-susceptible MIC. Sequencing of blaZ and multilocus sequence typing (MLST) were performed. Clinical outcomes were assessed in 77 patients treated with cefazolin. The blaZ gene was detected in 92 % of the 220 MSSA isolates. Type C β-lactamase was the most common (53 %), followed by type B (20 %) and type A (17 %). Certain genotypes were significantly associated with specific β-lactamase types (notably, ST30 and type A β-lactamase). A pronounced cefazolin InE was observed in 13 % of isolates. Most of these (79 %) expressed type A β-lactamase and ST30 was the predominant (55 %) clone amongst them. Cefazolin treatment failure was not observed in patients infected with strains exhibiting a pronounced InE. These strains had no impact on other clinical outcomes. In conclusion, the prevalence of a pronounced InE with cefazolin could be dependent upon distributions of MSSA genotypes. Cefazolin can likely be used for the treatment of MSSA bacteraemia (except endocarditis), without consideration of an InE.

Electro-optic switching in phase-discontinuity complementary metasurface twisted nematic cell

Electro-optic switching of refraction is experimentally demonstrated in a phase-discontinuity complementary metasurface twisted nematic cell. The phase-discontinuity complementary metasurface is fabricated by focused-ion-beam milling, and a twisted nematic cell is constructed with complementary V-shape slot antenna metasurface. By application of an external voltage, switching is achieved between ordinary refraction and extraordinary refraction satisfying the generalized Snell's law. It has a strong implication for applications in spatial light modulation and wavelength division multiplexer/demultiplexer in a near-IR spectral range.

Outbreak among healthy newborns due to a new variant of USA300-related meticillin-resistant Staphylococcus aureus

BACKGROUND

The prevalence of community-associated meticillin-resistant Staphylococcus aureus (CA-MRSA) is increasing throughout the world and is an important cause of skin and soft tissue infection (SSTI) in children and neonates.

AIM

To describe the successful control of an outbreak caused by a new strain of CA-MRSA in a newborn nursery.

METHODS

The investigation of the outbreak in July 2012 is reported with the control measures taken. Molecular typing of the MRSA isolates was performed.

FINDINGS

An outbreak of SSTI caused by CA-MRSA occurred in a newborn nursery. Six neonates were infected in a one-month period [infection rate: 8.5% (6/71)]. A new variant of CA-MRSA was responsible, which was characterized as USA300-related, Panton-Valentine Leucocidin (PVL) positive, arginine catabolic mobile element (ACME) negative, sequence type 8 (ST8), staphylococcal cassette chromosome mec (SCCmec) type IVa, agr type I and spa type t008. The outbreak among term neonates followed a rapid transmission pattern and was successfully controlled by implementing various outbreak control measures, including universal chlorhexidine bathing.

CONCLUSION

This is the first report of a hospital outbreak caused by a USA300-related CA-MRSA clone in Korea. Early recognition and reinforcement of infection control measures are important in decreasing transmission of CA-MRSA in a hospital setting.

Preliminary physical and electromagnetic design for the injector of the heavy ion superconducting linac

The Rare Isotope Science Project in Korea has developed a high current heavy ion accelerator using superconducting linacs. A normal conducting injector system was proposed to supply heavy ions to the superconducting driver linac. A beam physics and engineering design study was performed, and the beam dynamics of the injector was simulated. Optimized beam transmission and emittance were obtained from the beam dynamics simulation. Various normal conducting bunchers, such as multi-harmonic buncher, velocity equalizer, radiofrequency quadrupole, and re-bunchers, will be used and have been electromagnetically calculated.

Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

Reflection resonance switching in metamaterial twisted nematics cell

Electric switching of reflection resonances at near-IR spectral range is experimentally demonstrated in a reflective metamaterial twisted nematic liquid crystal cell. Reflective metamaterial composed of nano-sized double-split ring resonator aperture is fabricated by a focused ion beam milling. Two-fold rotational symmetry of double-split ring resonators allows for two orthogonal polarization-dependent reflection resonances in the reflective metamaterial. With an external voltage of 10V across 12μm cell gap, a full switching is achieved between two reflection resonances. Dynamic measurements show the time constants of switch-on and switch-off are in the order of 100ms and 10ms, respectively.

Obesity, diabetes, and survival outcomes in a large cohort of early-stage breast cancer patients

BACKGROUND

To determine the relationship between obesity, diabetes, and survival in a large cohort of breast cancer patients receiving modern chemotherapy and endocrine therapy.

PATIENTS AND METHODS

We identified 6342 patients with stage I-III breast cancer treated between 1996 and 2005. Patients were evaluated according to body mass index (BMI) category and diabetes status.

RESULTS

In a multivariate model adjusted for body mass index, diabetes, medical comorbidities, patient- and tumor-related variables, and adjuvant therapies, relative to the normal weight, hazard ratios (HRs) for recurrence-free survival (RFS), overall survival (OS), and breast cancer-specific survival (BCSS) for the overweight were 1.18 [95% confidence interval (CI) 1.02-1.36], 1.20 (95% CI 1.00-1.42), and 1.21 (95% CI 0.98-1.48), respectively. HRs for RFS, OS, and BCSS for the obese were 1.13 (95% CI 0.98-1.31), 1.24 (95% CI 1.04-1.48), and 1.23 (95% CI 1.00-1.52), respectively. Subset analyses showed these differences were significant for the ER-positive, but not ER-negative or HER2-positive, groups. Relative to nondiabetics, HRs for diabetics for RFS, OS, and BCSS were 1.21 (95% CI 0.98-1.49), 1.39 (95% CI 1.10-1.77), and 1.04 (95% CI 0.75-1.45), respectively.

CONCLUSIONS

In patients receiving modern adjuvant therapies, obesity has a negative impact on RFS, OS, and BCSS; and diabetes has a negative impact on RFS and OS. Control of both may be important to improving survival in obese and diabetic breast cancer patients.

Delayed post-hypoxic leucoencephalopathy presenting akinetic mutism after traumatic cervical cord injury: a case report

Delayed post-hypoxic leucoencephalopathy is a demyelinating syndrome characterized by acute onset of neuropsychiatric symptoms including parkinsonism or akinetic mutism that occurs days to weeks after recovery from cerebral hypo-oxygenation. We encountered a patient who presented with an akinetic mute state late after cervical cord injury without a definite hypoxic event.

Fabrication of polarization-dependent reflective metamaterial by focused ion beam milling

By focused ion beam milling, we fabricated near-IR reflective metamaterials consisting of nano-aperture arrays. Optimum parameters of ion beam current and accelerating voltage in the fabrication process are obtained. Nano-apertures constituting reflective metamaterial are successfully milled, and possess a reflective resonance in the near-IR spectral range. With a double-split-ring resonator structure for the nano-aperture, the intensity reflection at resonance is rendered polarization dependent. It is found that the point group symmetry of the nano-aperture array determines the amount of anisotropy in the intensity reflection. Finite-difference time-domain simulation was adopted to identify details of nano-aperture metastructures transferred from nano-aperture patterns by the focused ion beam milling.

[Grass genome and chromosome sets evolution]

This paper briefly discusses the mechanisms by which either diploid 2n or basal chromosome number x change during grass karyotype evolution.