A DN-mda5 transgenic zebrafish model demonstrates that Mda5 plays an important role in snakehead rhabdovirus resistance

Melanoma Differentiation-Associated protein 5 (MDA5) is a member of the retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) family, which is a cytosolic pattern recognition receptor that detects viral nucleic acids. Here we show an Mda5-dependent response to rhabdovirus infection in vivo using a dominant-negative mda5 transgenic zebrafish. Dominant-negative mda5 zebrafish embryos displayed an impaired antiviral immune response compared to wild-type counterparts that can be rescued by recombinant full-length Mda5. To our knowledge, we have generated the first dominant-negative mda5 transgenic zebrafish and demonstrated a critical role for Mda5 in the antiviral response to rhabdovirus.

Vertical components of head-shaking nystagmus in vestibular neuritis, Meniere's disease and migrainous vertigo

OBJECTIVES

To describe vertical and horizontal components of head-shaking nystagmus (HSN) in various vestibular disorders.

DESIGN

Retrospective case review.

SETTING

Tertiary care academic referral centre.

PARTICIPANTS

Head-shaking nystagmus was assessed in 66 vestibular neuritis (VN) patients at acute (<7 days) and follow-up (2 months), and 65 Meniere's disease (MD) and 76 migrainous vertigo (MV) in interictal period.

MAIN OUTCOME MEASURES

Head-shaking nystagmus was categorised as pure horizontal, pure vertical or mixed. Horizontal HSN was classified as monophasic or biphasic and paretic or recovery. Vertical HSN was classified as upbeat or downbeat.

RESULTS

Abnormal HSN (pathologic monophasic, biphasic or delayed-peak HSN) showed different positive rates depending on the vestibular disorders and compensation (94% in acute VN; 89% in FU VN; 78% in MD; 50% in MV). Paretic HSN with the nystagmus towards the lesioned side was the most common type in VN and MD; however, recovery HSN with the nystagmus towards the intact side could be rarely observed especially in patients with MD or compensated VN. Vertical nystagmus could be combined with horizontal HSN, and upbeat HSN was observed in most (83%) of the patients with acute VN, but downbeat HSN was common in follow-up VN (83%), MD (97%) and MV (85%). Weak perverted HSN, which is assumed to be a central nystagmus, was rarely observed in MD and MV (6-9%), but not in VN.

CONCLUSIONS

Head-shaking nystagmus (HSN) in horizontal plane is a valuable tool in the assessment of vestibular imbalance. Common observation of upbeat HSN in acute VN and downbeat HSN in follow-up VN, MD and MV suggests that vertical components are possibly related to the involvement of vestibular apparatus and compensation. Weak perverted HSN and delayed-peak HSN were rarely observed in MD and MV, and never observed in VN, suggesting that it is possibly related to either asymmetrically impaired vertical canals or misorientation of the velocity-storage system.

A genetic variation in microRNA target site of KRT81 gene is associated with survival in early-stage non-small-cell lung cancer

BACKGROUND

MicroRNAs (miRNAs) have a key role in carcinogenesis through negative regulation of their target genes. Therefore, genetic variations in miRNAs or their target sites may affect miRNA-mRNA interactions, thereby result in altered expression of target genes. This study was conducted to investigate the associations between single-nucleotide polymorphisms (SNP) located in the miRNA target sites (poly-miRTSs) and survival of patients with early-stage non-small-cell lung cancer (NSCLC).

METHODS

Using public SNP database and miRNA target sites prediction program, 354 poly-miRTSs were selected for genotyping. Among these, 154 SNPs applicable to Sequenom's MassARRAY platform were investigated in 357 patients. A replication study was carried out on an independent patient population (n = 479). Renilla luciferase assay and reverse transcription-polymerase chain reaction were conducted to examine functional relevance of potentially functional poly-miRTSs.

RESULTS

Of the 154 SNPs analyzed in a discovery set, 14 SNPs were significantly associated with survival outcomes. Among these, KRT81 rs3660G>C was found to be associated with survival outcomes in the validation cohort. In the combined analysis, patients with the rs3660 GC + CC genotype had a significantly better overall survival compared with those with GG genotype [adjusted hazard ratio (aHR) for OS, 0.65; 95% confidence interval (CI) 0.50-0.85; P = 0.001]. An increased expression of the reporter gene for the C allele of rs3660 compared with the G allele was observed by luciferase assay. Consistently, the C allele was associated with higher relative expression level of KRT81 in tumor tissues.

CONCLUSION

The rs3660G>C affects KRT81 expression and thus influences survival in early-stage NSCLC. The analysis of the rs3660G>C polymorphism may be useful to identify patients at high risk of a poor disease outcome.

Interplay of spin-orbit interactions, dimensionality, and octahedral rotations in semimetallic SrIrO(3)

We employ reactive molecular-beam epitaxy to synthesize the metastable perovskite SrIrO(3) and utilize in situ angle-resolved photoemission to reveal its electronic structure as an exotic narrow-band semimetal. We discover remarkably narrow bands which originate from a confluence of strong spin-orbit interactions, dimensionality, and both in- and out-of-plane IrO(6) octahedral rotations. The partial occupation of numerous bands with strongly mixed orbital characters signals the breakdown of the single-band Mott picture that characterizes its insulating two-dimensional counterpart, Sr(2)IrO(4), illustrating the power of structure-property relations for manipulating the subtle balance between spin-orbit interactions and electron-electron interactions.

Radiologic and laboratory differences in patients with tuberculous and parapneumonic pleural effusions showing non-lymphocytic predominance and high adenosine deaminase levels

PURPOSE

Tuberculous pleural effusion (TPE) is characterized by lymphocytic predominance and high adenosine deaminase (ADA) levels. However, TPEs sometimes present non-lymphocytic predominance, and parapneumonic effusion (PPE) often exceeds the cutoff value of ADA for TPE. Thus, the differential diagnosis of cases with pleural fluid (PF) showing non-lymphocytic predominance and high ADA levels is challenging. However, limited data concerning the clinical differences in these patients are available.

METHODS

A retrospective study was conducted on TPE and PPE patients with PF showing non-lymphocytic predominance and ADA levels ≥40 U/L in 2009-2013 in a South Korean tertiary referral hospital. The clinical, laboratory, and computed tomography (CT) findings between the groups were analyzed using multivariate logistic regression to develop a prediction model with independent factors for TPE.

RESULTS

Among 353 patients with TPE, 24 (6.8 %) showed PF with non-lymphocytic predominance and ADA levels of ≥40 U/L. Twenty-eight PPE patients who presented PF findings comparable with those of TPE patients were included in the control group. In the final analysis, PF ADA levels >58 U/L and nodular lung lesions on CT were independent positive predictors, while loculated effusion was an independent negative predictor for TPE. Using the prediction model, a score ≥ +3 provided a sensitivity of 88 %, specificity of 93 %, positive predictive value of 91 %, and negative predictive value of 90 % for TPE.

CONCLUSION

PF ADA levels, nodular lung lesions, and loculated pleural effusion may help differentiate TPE from PPE in patients with PF showing non-lymphocytic predominance and ADA levels ≥40 U/L.

Characterization of novel microsatellite markers derived from Korean rose bitterling (Rhodeus uyekii) genomic library

Korean rose bitterling (Rhodeus uyekii) is a freshwater fish endemic to Korea. Natural populations of this species have experienced severe declines as a result of habitat fragmentation and water pollution. To conserve and restore R. uyekii, the genetic diversity of this species needs to be assessed at the population level. Eighteen novel polymorphic microsatellite loci for R. uyekii were developed using an enriched partial genomic library. Polymorphisms at these loci were studied in 150 individuals collected from three populations. The number of alleles at each locus ranged from 3 to 47 (mean = 17.1). Within the populations, the observed heterozygosity ranged from 0.032 to 1.000, expected heterozygosity from 0.082 to 0.967, and polymorphism information content from 0.078 to 0.950. Six loci showed significant deviation from Hardy-Weinberg equilibrium after Bonferroni's correction, and no significant linkage disequilibrium was detected between most locus pairs, except in three cases. These highly informative microsatellite markers should be useful for genetic population structure analyses of R. uyekii.

The effect of a Foley catheter balloon on cervical ripening

The Foley catheter balloon may affect cervical ripening through changes in biochemical mediators by immunoassay and immunohistochemistry, when it is used for pre-induction cervical ripening. The aim of the study was to evaluate the changes in the biochemical mediators from the extra-amniotic space and immunohistochemistry in ripened cervical tissue after the insertion of a Foley catheter balloon (FCB) for pre-induction cervical ripening. A total of 18 pregnant women with a Bishop's score < 6, who were undergoing labour induction, were evaluated in this prospective study. The FCB was irrigated with 10 ml of phosphate buffered saline and the irrigant was collected 0, 2, 4 and 8 h after placement of the FCB or until spontaneous expulsion of the FCB occurred. Irrigant specimens were also collected from 10 spontaneous labouring (SL) women in the active phase of labour. The levels of interleukin (IL)-6, IL-8, matrix metalloproteinase (MMP)-8 and NO were measured. Cervical specimens were obtained from 12 women, including four undergoing induction; four SL and four non-pregnant (NP) women. Immunohistochemical staining was performed to localise hyaluronic acid synthase (HAS)-1, IL-6, IL-8, MMP-8, endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS). Results showed that the levels of IL-6, IL-8, and MMP-8 significantly increased over time in FCB group (p < 0.01). In the immunohistochemical analysis of cervical tissues, immunoreactivity of HAS-1 in the after FCB group was stronger than any of the other groups. The protein expressions of IL-6, IL-8, MMP-8, eNOS and iNOS were more prominent in the after FCB and SL groups than in the NP and the before FCB groups. iNOS was only observed in the after FCB and SL groups. It was concluded that FCB may affect cervical ripening through changes in biochemical mediators by immunoassay and immunohistochemistry, when it is used for pre-induction cervical ripening.

Endovascular treatment of ophthalmic artery aneurysms: assessing balloon test occlusion and preservation of vision in coil embolization

BACKGROUND AND PURPOSE

ICA-ophthalmic artery aneurysms have unique configurations corresponding to relative risks of ophthalmologic morbidities. Presented herein are clinical and radiologic outcomes of coil embolization in ophthalmic artery aneurysms.

MATERIALS AND METHODS

From January 2003 to September 2013, endovascular coiling was performed in 43 consecutive patients with ophthalmic artery aneurysms, each classified by the degree to which the ophthalmic artery was incorporated by the aneurysm and the contiguity between the ophthalmic artery entry and parent ICA. Clinical and radiologic outcomes of this approach were investigated, including the technical aspects of treatment and the efficacy of balloon test occlusion.

RESULTS

Among 14 patients (32.6%, all ophthalmic artery types) undergoing balloon test occlusion before endovascular coiling, patent collaterals between the external carotid artery and ophthalmic artery were demonstrated in 12 (85.7%) and complete compromise of the ophthalmic artery (without affecting vision) occurred in 4 patients during coiling. Steam-shaped S-configured (67.9%) or straight microcatheters (17.8%) facilitated aneurysm selection in most of the superiorly directed ophthalmic artery aneurysms (n = 28), and steam-shaped pigtail microcatheters (85.7%) were useful in medially directed aneurysms (n = 14). Balloon protection (n = 22) was generally used to facilitate coiling, or a stent (n = 9) was alternatively deployed. Satisfactory aneurysmal occlusion was achieved through coil embolization in 37 lesions (86.1%). During follow-up of 35 patients (mean interval, 12.9 ± 9.4 months), only 1 instance (2.9%) of major recanalization was observed.

CONCLUSIONS

If one tailors technical strategies, ophthalmic artery aneurysms are amenable to safe and effective endovascular coil embolization, which tends to be stable in follow-up. Balloon test occlusion may be helpful in devising treatment strategies to preserve vision when coiling ophthalmic artery aneurysms (especially those incorporating an ophthalmic artery origin) is done.

Determination of SK3497 in rat plasma and its application in a pharmacokinetic study of SK3497

In this study, a sensitive and reliable method for the quantitation of SK3497 in rat plasma was developed and validated using high performance liquid chromatography. The plasma samples were prepared by deproteinization, and sildenafil was used as an internal standard. Chromatographic separation was achieved using a reversed-phase (C18) column. The mobile phase, 0.02 M ammonium acetate buffer:acetonitrile (45:55, v/v), was run at a flow rate of 1.0 mL/min, and the column eluent was monitored using an ultraviolet detector at 254 nm at room temperature. The retention times of sildenafil (an internal standard), and SK3497 were approximately 5.6 and 8.3 min, respectively. The detection limit of SK3497 in rat plasma was 0.03 μg/mL. Pharmacokinetic parameters of SK3497 was evaluated after intravenous (i. v.; at doses of 15 mg/kg) and oral (p.o.; at doses of 30 mg/kg) administration of SK3497 in rats. After p.o. administration (30 mg/kg) of SK3497, F-value was approximately 53.0%. The protein binding of SK3497 to 4% human serum albumin were also described.

Comparison of the incidence between tuberculosis and nontuberculous mycobacterial disease after gastrectomy

PURPOSE

Gastrectomy is a well-known risk factor for tuberculosis (TB). However, little data are available regarding the relationship between gastrectomy and the risk of nontuberculous mycobacterial (NTM) disease. Here, we investigated the incidence of TB and NTM lung disease in gastrectomized patients.

METHOD

New cases of TB and NTM lung infection or disease were examined among patients who had undergone gastrectomy due to gastric cancer from 2003 to 2009 at a tertiary referral hospital in South Korea. Annualized incidence rates for cases were compared with those of the general population.

RESULTS

This study included a total of 2,684 patients. New mycobacterial cases were found in 41 patients. Cases of TB and NTM lung infection were 35 (85 %) and 6 (15 %) including 2 NTM lung disease cases, respectively. Annualized crude incidence rates for TB, NTM lung infection, and NTM lung disease were 327/100,000, 56/100,000, and 19/100,000, respectively. The age-standardized incidence rate of TB was significantly higher in gastrectomized patients than in the general population. However, the standardized incidences of NTM lung infection and disease were not significantly different from those of non-gastrectomized patients. Patients with NTM lung infection frequently exhibited comorbid chronic lung disease, while those with TB were more frequently found to have fibronodular lesions on preoperative chest radiography.

CONCLUSIONS

Gastrectomy does not appear to increase the risk of NTM lung disease. However, NTM lung infection or disease should be considered as a differential diagnosis of pulmonary TB in gastrectomized patients accompanying chronic lung disease.

Posterior Communicating Artery Compromise in Coil Embolization of Posterior Communicating Artery Aneurysms

PURPOSE

Whether the posterior communicating artery (PcomA) can be safely compromised during endovascular treatment of a PcomA aneurysm is a matter of debate. Here we present clinical and radiologic outcomes, given this scenario.

METHODS

From data prospectively accrued between January 2004 and December 2012, records of 44 patients harboring 46 PcomA aneurysms were retrieved. All had suffered PcomA compromise in the course of endovascular coil embolization. Patients/aneurysms were stratified into those with complete (Group A) and incomplete (Group B) compromise depending on the degree of PcomA flow limitation documented by postembolization ipsilateral internal carotid artery angiography. Clinical and radiologic outcomes were accordingly assessed.

RESULTS

All affected vessels were hypoplastic PcomA variants (PcomA/P1 ratio, ≤ 1.0), with exception of a single dominant PcomA (PcomA/P1 ratio, 1.1). In Group A (23 patients, 23 aneurysms), no PcomA compromise-related infarction was evident, whereas in Group B (21 patients, 23 aneurysms), two ischemic events occurred. One patient suffered thalamic infarction, although patency of the PcomA was adequate in a follow-up angiogram, and another experienced a transient ischemic attack.

CONCLUSION

Our findings suggest that obstructed flow in hypoplastic PcomA variants during coil embolization of PcomA aneurysms carries no major consequence. However, incomplete compromise of the PcomA may be a source of delayed thromboembolic infarction.

Exposure to secondhand tobacco smoke and lung cancer by histological type: a pooled analysis of the International Lung Cancer Consortium (ILCCO)

While the association between exposure to secondhand smoke and lung cancer risk is well established, few studies with sufficient power have examined the association by histological type. In this study, we evaluated the secondhand smoke-lung cancer relationship by histological type based on pooled data from 18 case-control studies in the International Lung Cancer Consortium (ILCCO), including 2,504 cases and 7,276 control who were never smokers and 10,184 cases and 7,176 controls who were ever smokers. We used multivariable logistic regression, adjusting for age, sex, race/ethnicity, smoking status, pack-years of smoking, and study. Among never smokers, the odds ratios (OR) comparing those ever exposed to secondhand smoke with those never exposed were 1.31 (95% CI: 1.17-1.45) for all histological types combined, 1.26 (95% CI: 1.10-1.44) for adenocarcinoma, 1.41 (95% CI: 0.99-1.99) for squamous cell carcinoma, 1.48 (95% CI: 0.89-2.45) for large cell lung cancer, and 3.09 (95% CI: 1.62-5.89) for small cell lung cancer. The estimated association with secondhand smoke exposure was greater for small cell lung cancer than for nonsmall cell lung cancers (OR=2.11, 95% CI: 1.11-4.04). This analysis is the largest to date investigating the relation between exposure to secondhand smoke and lung cancer. Our study provides more precise estimates of the impact of secondhand smoke on the major histological types of lung cancer, indicates the association with secondhand smoke is stronger for small cell lung cancer than for the other histological types, and suggests the importance of intervention against exposure to secondhand smoke in lung cancer prevention.

Emergency medicine resident well-being: stress and satisfaction

BACKGROUND

Emergency medicine (EM) residents are exposed to many work-related stressors, which affect them both physically and emotionally. It is unknown, however, how EM residents perceive the effect of these stressors on their well-being and how often they use unhealthy coping mechanisms to manage stress.

AIMS

To evaluate EM residents' perceptions of stressors related to their overall well-being and the prevalence of various coping mechanisms.

METHODS

An online survey instrument was developed to gauge resident stress, satisfaction with current lifestyle, stress coping mechanisms and demographics. A stratified random sample of EM residents from three postgraduate years (PGY-I, PGY-II and PGY-III) was obtained. Descriptive statistics and one-way analysis of variance were used to compare residents across PGY level.

RESULTS

There were 120 potential participants in each of the three PGYs. The overall response rate was 30% (109) with mean age of 30 and 61% were male. On a 0-4 scale (0 = completely dissatisfied), respondents in PGY-I reported significantly less satisfaction with lifestyle than those in PGY-II and III (mean rating: 1.29, 1.66 and 1.70, respectively; P < 0.001). There were no significant differences in mean ratings between PGYs on each of the other stress categories: work relationships (1.37), work environment (1.10) and response to patients (1.08). Residents reported exercise (94%), hobbies (89%) and use of alcohol (71%) as coping methods.

CONCLUSIONS

Residents reported low satisfaction with current lifestyle. This dissatisfaction was unrelated to perceived work-related stress. Some undesirable coping methods were prevalent, suggesting that training programs could focus on promotion of healthy group activities.

An extended medial to lateral approach to mobilize the splenic flexure during laparoscopic low anterior resection

AIM

The aim of this retrospective study of laparoscopic low anterior resection was to compare splenic flexure mobilization (SFM) carried out by an extended medial to lateral approach with that by a lateral approach.

METHOD

Records of patients with rectal cancer on a prospectively maintained database undergoing laparoscopic low anterior resection performed between January 2009 and November 2011 by a single surgeon were analysed. The extended medial to lateral approach involved continuing the medial to lateral approach upwards to enter the lesser sac over the pancreas, thus permitting detachment of the splenic flexure.

RESULTS

Two hundred and thirty-seven patients, including 164 undergoing a lateral SFM and 73 an extended medial to lateral SFM, were evaluated. Both patient groups had similar characteristics except for operative time (152.7 ± 32.7 min extended medial to lateral; 171.5 ± 40.8 min lateral; P < 0.001), postoperatively the interval to oral intake (3.1 ± 0.8 days extended medial to lateral; 3.7 ± 0.9 lateral; P < 0.001) and duration of hospital stay (8.2 ± 2.8 days extended medial to lateral; 10.3 ± 7.5 days lateral; P = 0.002) favoured the extended medial to lateral group.

CONCLUSION

An extended medial to lateral approach for SFM during laparoscopic low anterior resection of rectal cancer appears to be an improvement over the previously used lateral approach, because it may provide a shorter operation time and shorter hospital stay.

Predictive factors for tuberculosis in patients with a TB-PCR-negative bronchial aspirate

PURPOSE

Pulmonary tuberculosis (PTB), with a tuberculosis (TB)-polymerase chain reaction (PCR)-negative bronchial aspirate (BA), but a positive culture result is often encountered in clinical practice. However, limited data are available concerning clinical judgment in patients with suspected PTB and a TB-PCR-negative BA pending culture results. The present study aimed to identify predictors for PTB in patients with a TB-PCR-negative BA.

METHODS

A retrospective study was conducted on patients who had undergone a bronchoscopy because of suspected PTB. Clinical, laboratory, and computed tomography (CT) findings were investigated in PTB patients with TB-PCR-negative but positive culture BA results, and non-PTB patients with a radiographic lesion comparable to the former.

RESULTS

Of 250 patients screened, 31 (12 %) were diagnosed with PTB by positive culture results only. Of these 31 patients, 30 (97 %) had a lesion within one-third of the hemithorax as determined by chest radiography. In the final analysis of 30 PTB and 65 non-PTB patients with comparable radiographic lesions, a positive QuantiFERON-TB Gold In-Tube (QFT) result was independently associated with an increased risk of a positive TB culture. CT findings of consolidation were a negative predictor for PTB. Patients with a negative QFT result and consolidation had a negative predictive value of 95 % for PTB, while patients with a positive QFT result and nodular CT abnormalities without consolidation had a positive predictive value of 86 % for PTB.

CONCLUSION

The simple combination of CT findings of consolidation and QFT test results may help clinicians to refine decision-making in patients with a TB-PCR-negative BA.

Effect of dietary supplementation of Lactobacillus-fermented Artemisia princeps on growth performance, meat lipid peroxidation, and intestinal microflora in Hy-line Brown male chickens

The objective of this experiment was to investigate the effect of dietary supplementation of Lactobacillus-fermented Artemisia princeps (LFA) on growth performance, meat lipid peroxidation, and intestinal microflora in Hy-line Brown male chickens. A total of six hundred twenty-four 1-d-old Hy-Line Brown male chicks were randomly allotted to 3 dietary treatments with 4 replicated pens consisting of 52 chicks. The control diet was formulated to be adequate in energy and nutrients. Two additional diets were prepared by adding 2.5 or 5.0 g/kg of LFA to the control diet. The experimental diets were fed on an ad libitum basis to the birds during 7 wk. Body weight gain and feed intake were recorded at 2 and 7 wk. At the end of the experiment, 2 birds from each treatment were killed by cervical dislocation and the samples for ileal content, breast, and thigh meat were collected for the determination of meat lipid peroxidation and microbial population. Results indicated that increasing inclusion level of LFA in diets improved BW gain (linear and quadratic, P < 0.05) and tended to improve feed efficiency (linear and quadratic, P < 0.10) of birds during 0 to 7 wk. Feeding the diets containing increasing amounts of LFA to birds reduced (quadratic, P < 0.05) thiobarbituric acid-reactive substance (TBARS) values in breast and thigh meat during 15 d of storage. The concentrations of Lactobacillus spp. in the ileal content of birds increased (linear and quadratic, P < 0.05), but those of Salmonella spp. tended to be decreased (quadratic, P < 0.10) as inclusion level of LFA in diets increased. These results suggest that dietary LFA may be used as a functional ingredient to improve growth performance, meat lipid stability, and intestinal health of birds.

Prevalence and clinical characteristics of diabetic peripheral neuropathy in hospital patients with Type 2 diabetes in Korea

AIMS

Diabetic peripheral neuropathy is a common complication of diabetes. This cross-sectional study investigated the prevalence and clinical characteristics of this neuropathy in patients with Type 2 diabetic mellitus treated at hospitals in Korea.

METHODS

Questionnaires and medical records were used to collect data on 4000 patients with Type 2 diabetes from the diabetes clinics of 40 hospitals throughout Korea. Diabetic peripheral neuropathy was diagnosed based on a review of medical records or using the Michigan Neuropathy Screening Instrument score and monofilament test.

RESULTS

The prevalence of neuropathy was 33.5% (n = 1338). Multivariate analysis revealed that age, female sex, diabetes duration, lower glycated haemoglobin, treatment with oral hypoglycaemic agents or insulin, presence of retinopathy, history of cerebrovascular or peripheral arterial disease, presence of hypertension or dyslipidaemia, and history of foot ulcer were independently associated with diabetic peripheral neuropathy. Of the patients with neuropathy, 69.8% were treated for the condition and only 12.6% were aware of their neuropathy.

CONCLUSION

There was a high prevalence of peripheral neuropathy in patients with Type 2 diabetes in Korea and those patients were far more likely to have complications or co-morbidities. The proper management of diabetic peripheral neuropathy deserves attention from clinicians to ensure better management of diabetes in Korea.

Blood donors on teratogenic drugs and donor deferral periods in a clinical situation

Deferral of blood donors taking teratogenic drugs is critical. From March 2008 to January 2009, we analysed stored blood specimens from donors who had taken teratogenic drugs and whose blood was transfused to women of childbearing age to determine the plasma concentration at the time of donation using high-performance liquid chromatography. In total, 167 specimens were examined. The numbers of specimens exceeding the quantification limit were 7, 39, 4, 2 and 1 for finasteride, isotretinoin, acitretin, etretinate and dutasteride, respectively. Finasteride was beyond the recommended drug deferral period in one specimen. These results may help create practical deferral policies.

Cryobanking of Korean allium germplasm collections: results from a 10 year experience

This paper reviews a 10-year experience in establishing a cryopreserved Allium germplasm collection at the genebank of the National Agrobiodiversity Center, Republic of Korea. A systematic approach to Allium cryopreservation included: 1. revealing the most critical factors that affected regeneration after cryostorage; 2. understanding the mechanisms of cryoprotection by analyzing the thermal behavior of explants and cryoprotectant solutions using DSC and influx/efflux of cryoprotectants using HPLC; 3. assessing genetic stability of regenerants; and 4. revealing the efficiency of cryotherapy. Bulbil primordia, i.e. asexual bulbs formed on unripe inflorescences, proved to be the most suitable material for conservation of bolting varieties due to high post-cryopreservation regrowth and lower microbial infection level, followed by apical shoot apices from single bulbs and cloves. A total of 1,158 accessions of garlic as well as some Allium species have been cryopreserved during 2005-2010 using the droplet-vitrification technique with a mean regeneration percentage of 65.9 percent after cryostorage. These results open the door for large-scale implementation of cryostorage and for simplifying international exchange for clonal Allium germplasm.

Production of human papillomavirus type 33 L1 major capsid protein and virus-like particles from Bacillus subtilis to develop a prophylactic vaccine against cervical cancer

We developed a bacterial expression system to produce human papillomavirus (HPV) type 33 L1 major capsid protein and virus-like particles from a recombinant Bacillus subtilis strain. For the first time, we have isolated self-assembled virus-like particles (VLPs) of HPV type 33 from B. subtilis, a strain generally recognized as safe (GRAS). The gene encoding the major capsid protein L1 of HPV type 33 was amplified from viral DNA isolated from a Korean patient and expressed in B. subtilis; a xylose-induction system was used to control gene activity. HPV33 L1 protein was partially purified by 40% (w/v) sucrose cushion centrifugation and strong cation exchange column chromatography. Eluted samples exhibited immunosignaling in fractions of 0.5-1.0 M NaCl. The HPV33 L1 protein was shown to be approximately 56 kDa in size by SDS-PAGE and Western blotting; recovery and purity were quantified by indirect immuno-ELISA assay. The final yield and purity were approximately 20.4% and 10.3%, respectively. Transmission electron microscopic analysis of fractions immunoactive by ELISA revealed that the L1 protein formed self-assembled VLPs with a diameter of approximately 20-40 nm. Humoral and cellular immune responses provoked by the B. subtilis/HPV33 L1 strain were approximately 100- and 3-fold higher than those of the empty B. subtilis strain as a negative control, respectively. Development of a VLP production and delivery system using B. subtilis will be helpful, in that the vaccine may be convenient production as an antigen delivery system. VLPs thus produced will be safer for human use than those purified from Gram-negative strains such as Escherichia coli. Also, use of B. subtilis as a host may aid in the development of either live or whole cell vaccines administered by antigen delivery system.

The bone marrow-expressed antimicrobial cationic peptide LL-37 enhances the responsiveness of hematopoietic stem progenitor cells to an SDF-1 gradient and accelerates their engraftment after transplantation

We report that the bone marrow (BM) stroma-released LL-37, a member of the cathelicidin family of antimicrobial peptides, primes/increases the responsiveness of murine and human hematopoietic stem/progenitor cells (HSPCs) to an α-chemokine stromal-derived factor-1 (SDF-1) gradient. Accordingly, LL-37 is upregulated in irradiated BM cells and enhances the chemotactic responsiveness of hematopoietic progenitors from all lineages to a low physiological SDF-1 gradient as well as increasing their (i) adhesiveness, (ii) SDF-1-mediated actin polymerization and (iii) MAPK(p42/44) phosphorylation. Mice transplanted with BM cells ex vivo primed by LL-37 showed accelerated recovery of platelet and neutrophil counts by ∼3-5 days compared with mice transplanted with unprimed control cells. These priming effects were not mediated by LL-37 binding to its receptor and depended instead on the incorporation of the CXCR4 receptor into membrane lipid rafts. We propose that LL-37, which has primarily antimicrobial functions and is harmless to mammalian cells, could be clinically applied to accelerate engraftment as an ex vivo priming agent for transplanted human HSPCs. This novel approach would be particularly important in cord blood transplantations, where the number of HSCs available is usually limited.

Conditioning for hematopoietic transplantation activates the complement cascade and induces a proteolytic environment in bone marrow: a novel role for bioactive lipids and soluble C5b-C9 as homing factors

We have observed that conditioning for hematopoietic transplantation by lethal irradiation induces a proteolytic microenvironment in the bone marrow (BM) that activates the complement cascade (CC). As a result, BM is enriched for proteolytic enzymes and the soluble form of the terminal product of CC activation, the membrane attack complex C5b-C9 (MAC). At the same time, proteolytic enzymes induced in irradiated BM impair the chemotactic activity of α-chemokine stromal-derived factor-1 (SDF-1). As SDF-1 is considered a crucial BM chemoattractant for transplanted hematopoietic stem/progenitor cells (HSPCs), we sought to determine whether other factors that are resistant to proteolytic enzymes have a role in this process, focusing on proteolysis-resistant bioactive lipids. We found that the concentrations of sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P) increase in the BM after conditioning for transplantation and that both S1P and, as we show here for the first time, C1P are potent chemoattractants for HSPCs. Next, we observed that C5-deficient mice that do not generate MAC show impaired engraftment of HSPCs. In support of a role for MAC in homing and engraftment, we found that soluble MAC enhances in a CR3 (CD11b/CD18)-dependent manner the adhesion of HSPCs to BM stromal cells and increases the secretion of SDF-1 by BM stroma. We conclude that an increase in BM levels of proteolytic enzyme-resistant S1P and C1P and activation of CC, which leads to the generation of MAC, has an important and previously underappreciated role in the homing of transplanted HSPCs.