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1.  Radiological findings and clinical features of thoracic immunoglobulin G4-positive plasma cell granuloma: two cases 
The British Journal of Radiology  2010;83(991):e150-e153.
Plasma cell granulomas, inflammatory pseudotumours and myofibroblastomas are synonymous with characteristic plasma cell infiltration in various body organs including the pancreas, liver, retroperitoneum and mediastinal structures causing idiopathic fibrosclerosis. Recently, a new concept has arisen regarding the relationship between immunoglobulin (Ig)G4-positive cell infiltration and idiopathic systemic fibrosclerosis. We report two cases showing IgG4-positive cell infiltration in the lung presenting as lung nodules with or without extrapulmonary manifestations.
PMCID: PMC3473664  PMID: 20603401
2.  Genetic susceptibility to COPD 
Thorax  2000;55(8):722.
PMCID: PMC1745824  PMID: 10950722
3.  Epidemiologic and clinical survey of Behcet's disease in Korea: the first multicenter study. 
Journal of Korean Medical Science  2001;16(5):615-618.
The prevalence of Behcet's disease is the highest in the East Asian and the Mediterranean countries. Behcet's disease is also distributed in the Asian countries, but the nationwide survey has not been performed in Korea yet. The Korean Study Group for Behcet's Disease, founded in 1999, conducted a multicenter, retrospective survey on epidemiologic and clinical features of the patients with Behcet's disease from 20 hospitals around the nation from 1997 to 1999. Of 3,497 patients, 1,527 were classified into complete or incomplete type of Behcet's disease according to the revised Shimizu's classification. The sex ratio was 1:1.75 with the female predominance. Geographical distribution showed the highest frequency in Seoul (38.5%). Clinically, 98.8% had oral ulcers, 83.2% had genital ulcers, 84.3% had skin lesions and 50.9% had ocular lesions. As for the minor clinical manifestations, articular symptoms were the most frequent. The pathergy test showed positive in 15.4% of patients and revealed a higher positive rate in males (20.2%) than in females (12.7%). In conclusion, we performed the first multicenter study on Behcet's disease in Korea and revealed the female predominance, higher frequency of ocular lesions, and lower positivity of pathergy test in the patients.
PMCID: PMC3057606  PMID: 11641532
4.  Epinephrine-induced arrhythmias: effects of thoracic epidural anesthesia and vagotomy during enflurane anesthesia in rabbits. 
Journal of Korean Medical Science  1999;14(2):133-137.
For evaluating the effects of thoracic epidural anesthesia, with or without bilateral vagotomy, epinephrine-induced arrhythmias were studied in 31 rabbits anesthetized with 1 minimum alveolar concentration of enflurane. We divided the rabbits into 5 groups: Group I (epidural saline as control group; n=6), Group II (epidural lidocaine without vagotomy; n=6), Group III (intravenous lidocaine; n=7), Group IV (epidural saline with vagotomy; n=6), and Group V (epidural lidocaine with vagotomy; n=6). Using logdose protocol, epinephrine was infused at an initial rate of 0.67 microg/kg/min and increased by Exp[0.4] until arrhythmias occurred; if arrhythmias occurred at any of these doses, a smaller dose, divided by Exp[0.2], was tested. Arrhythmic dose of epinephrine was defined as the smallest infusion rate needed to produce four or more arrhythmias within 15 sec during epinephrine infusion. Arrhythmic dose of epinephrine and its plasma concentration in epidural lidocaine group were significantly higher than control (p<0.05). Similarity of results was also noted amongst the intravenous lidocaine group, vagotomy only group, and vagotomized epidural lidocaine group with respect to the control. These results suggest that thoracic epidural anesthesia raises the threshold for enflurane-epinephrine induced arrhythmias in rabbits and that this effect is eliminated by bilateral vagotomy.
PMCID: PMC3054358  PMID: 10331557
5.  Arthritic manifestations of inflammatory bowel disease. 
Inflammatory bowel disease (IBD) is commonly associated with arthritic manifestations. They are divided into three clinical categories; peripheral arthritis, spondylitis, and sacroiliitis. To evaluate the incidence of arthritis associated with IBD in Korea, we retrospectively reviewed one hundred and twenty-nine patients with IBD, 77 with ulcerative colitis (UC) and 52 with Crohn's disease (CD). Arthritis occurred in twenty-two patients (17.1%); 15 with UC(19.6%), 7 with CD (13.5%). Patients with arthritis had more active inflammations and all were seronegative except one patient. Peripheral arthritis was found in twenty patients (15.5%) and more common in UC (19.6%) than in CD (9.6%). Joint involvements tended to be monoarticular or pauciarticular, and most frequently developed in the knee and ankle. Spondylitis was diagnosed in one patient (1.6%) who showed HLA B27 positivity. Radiographic sacroiliitis was observed in eight patients (6.2%) who revealed HLA B27 negativity. Both peripheral arthritis and sacroiliitis were found in six patients (4.6%). In CD, arthritis occurred in 20% of the patients with colonic involvement but in none of the patients without colonic involvement. In conclusion, arthritis was frequent in patients with IBD. Peripheral arthritis was more common in patients with UC than CD. All the patients with CD and arthritis had colonic involvement.
PMCID: PMC3054342  PMID: 9539317
6.  The activity of the high-affinity K+ uptake system Kdp sensitizes cells of Escherichia coli to methylglyoxal. 
Journal of Bacteriology  1996;178(13):3957-3961.
Expression of the Kdp system sensitizes cells to methylglyoxal (MG) whether this electrophile is added externally or is synthesized endogenously. The basis of this enhanced sensitivity is the maintenance of a higher cytoplasmic pH (pHi) in cells expressing Kdp. In such cells, MG elicits rapid cytoplasmic acidification via KefB and KefC, but the steady-state pHi attained is still too high to confer protection Lowering pHi further by incubation with acetate increases the sensitivity of cells to MG.
PMCID: PMC232660  PMID: 8682804
7.  Incidence estimation of genitourinary cancer in Korea. 
A nation-wide study was performed to estimate the incidence of bladder, kidney, renal pelvis and ureter, prostate, testicular and other genitourinary cancer among Koreans in Korea using medical records of the inpatients of the beneficiaries of the Korea Medical Insurance Corporation (KMIC) from Jan. 1, 1989 to Dec. 31, 1989. The crude incidence rate of bladder cancer (ICD-9 188) is estimated to be 4.43 and 0.98 per 100,000 in males and females, respectively. Around 1,093 new cases of bladder cancer (895 male and 198 female) are estimated to occur in a year. The adjusted rate for the world population is 7.76 in males and 1.19 in females which is similar to that of Japanese in Osaka and Chinese in Shanghai, but lower than in American whites and blacks. The crude incidence of kidney, renal pelvis and ureteral cancer (ICD-9 189) is estimated to be 1.61 and 0.87 in males and females, respectively. Around 507 new cases of kidney, renal pelvis and ureteral cancer (332 male and 175 female) are estimated to occur in a year. The adjusted rate for the world population is 2.69 in males and 1.04 in females. In the prostate (ICD-9 185), the crude incidence rate of cancer is estimated to be 1.36. Around 274 new cases of prostate cancer are occurring in a year. The adjusted rate for the world population is 2.98 which is similar to the Chinese rate. The incidence of genitourinary cancer continuously increases with age.
PMCID: PMC3053813  PMID: 1524728
8.  Chemical Atherogenesis: Role of Endogenous and Exogenous Poisons in Disease Development 
Toxics  2014;2(1):17-34.
Chemical atherogenesis is an emerging field that describes how environmental pollutants and endogenous toxins perturb critical pathways that regulate lipid metabolism and inflammation, thus injuring cells found within the vessel wall. Despite growing awareness of the role of environmental pollutants in the development of cardiovascular disease, the field of chemical atherogenesis can broadly include both exogenous and endogenous poisons and the study of molecular, biochemical, and cellular pathways that become dysregulated during atherosclerosis. This integrated approach is logical because exogenous and endogenous toxins often share the same mechanism of toxicity. Chemical atherogenesis is a truly integrative discipline because it incorporates concepts from several different fields, including biochemistry, chemical biology, pharmacology, and toxicology. This review will provide an overview of this emerging research area, focusing on cellular and animal models of disease.
PMCID: PMC4333738
chemical atherogenesis; endogenous toxins; environmental pollutants; atherosclerosis; carboxylesterases; inflammation; oxidative stress
9.  Activated STING in a Vascular and Pulmonary Syndrome 
The New England journal of medicine  2014;371(6):507-518.
The study of autoinflammatory diseases has uncovered mechanisms underlying cytokine dysregulation and inflammation.
We analyzed the DNA of an index patient with early-onset systemic inflammation, cutaneous vasculopathy, and pulmonary inflammation. We sequenced a candidate gene, TMEM173, encoding the stimulator of interferon genes (STING), in this patient and in five unrelated children with similar clinical phenotypes. Four children were evaluated clinically and immunologically. With the STING ligand cyclic guanosine monophosphate–adenosine monophosphate (cGAMP), we stimulated peripheral-blood mononuclear cells and fibroblasts from patients and controls, as well as commercially obtained endothelial cells, and then assayed transcription of IFNB1, the gene encoding interferon-β, in the stimulated cells. We analyzed IFNB1 reporter levels in HEK293T cells cotransfected with mutant or nonmutant STING constructs. Mutant STING leads to increased phosphorylation of signal transducer and activator of transcription 1 (STAT1), so we tested the effect of Janus kinase (JAK) inhibitors on STAT1 phosphorylation in lymphocytes from the affected children and controls.
We identified three mutations in exon 5 of TMEM173 in the six patients. Elevated transcription of IFNB1 and other gene targets of STING in peripheral-blood mono-nuclear cells from the patients indicated constitutive activation of the pathway that cannot be further up-regulated with stimulation. On stimulation with cGAMP, fibro-blasts from the patients showed increased transcription of IFNB1 but not of the genes encoding interleukin-1 (IL1), interleukin-6 (IL6), or tumor necrosis factor (TNF). HEK293T cells transfected with mutant constructs show elevated IFNB1 reporter levels. STING is expressed in endothelial cells, and exposure of these cells to cGAMP resulted in endothelial activation and apoptosis. Constitutive up-regulation of phosphorylated STAT1 in patients’ lymphocytes was reduced by JAK inhibitors.
STING-associated vasculopathy with onset in infancy (SAVI) is an autoinflammatory disease caused by gain-of-function mutations in TMEM173.
PMCID: PMC4174543  PMID: 25029335
10.  Channel-mediated astrocytic glutamate modulates hippocampal synaptic plasticity by activating postsynaptic NMDA receptors 
Molecular Brain  2015;8:7.
Activation of G protein coupled receptor (GPCR) in astrocytes leads to Ca2+-dependent glutamate release via Bestrophin 1 (Best1) channel. Whether receptor-mediated glutamate release from astrocytes can regulate synaptic plasticity remains to be fully understood.
We show here that Best1-mediated astrocytic glutamate activates the synaptic N-methyl-D-aspartate receptor (NMDAR) and modulates NMDAR-dependent synaptic plasticity. Our data show that activation of the protease-activated receptor 1 (PAR1) in hippocampal CA1 astrocytes elevates the glutamate concentration at Schaffer collateral-CA1 (SC-CA1) synapses, resulting in activation of GluN2A-containing NMDARs and NMDAR-dependent potentiation of synaptic responses. Furthermore, the threshold for inducing NMDAR-dependent long-term potentiation (LTP) is lowered when astrocytic glutamate release accompanied LTP induction, suggesting that astrocytic glutamate is significant in modulating synaptic plasticity.
Our results provide direct evidence for the physiological importance of channel-mediated astrocytic glutamate in modulating neural circuit functions.
PMCID: PMC4320468  PMID: 25645137
Astrocytes; Bestrophin 1; Ca2+-activated anion channel; Synaptic plasticity; Glutamate; NMDA receptor; LTP; PAR1
11.  Responses of Blood Glucose, Insulin, Glucagon, and Fatty Acids to Intraruminal Infusion of Propionate in Hanwoo 
This study was carried out to investigate the effects of intraruminal infusion of propionate on ruminal fermentation characteristics and blood hormones and metabolites in Hanwoo (Korean cattle) steers. Four Hanwoo steers (average body wt. 270 kg, 13 month of age) equipped with rumen cannula were infused into rumens with 0.0 M (Water, C), 0.5 M (37 g/L, T1), 1.0 M (74 g/L, T2) and 1.5 M (111 g/L, T3) of propionate for 1 hour per day and allotted by 4×4 Latin square design. On the 5th day of infusion, samples of rumen and blood were collected at 0, 60, 120, 180, and 300 min after intraruminal infusion of propionate. The concentrations of serum glucose and plasma glucagon were not affected (p>0.05) by intraruminal infusion of propionate. The serum insulin concentration at 60 min after infusion was significantly (p<0.05) higher in T3 than in C, while the concentration of non-esterified fatty acid (NEFA) at 60 and 180 min after infusion was significantly (p<0.05) lower in the propionate treatments than in C. Hence, intraruminal infusion of propionate stimulates the secretion of insulin, and decreases serum NEFA concentration rather than the change of serum glucose concentration.
PMCID: PMC4283164  PMID: 25557815
Rumen; Propionate Infusion; Hormones; Steer
12.  Intermediate-risk grouping of cervical cancer patients treated with radical hysterectomy: a Korean Gynecologic Oncology Group study 
British Journal of Cancer  2013;110(2):278-285.
In this study, we sought to identify a criterion for the intermediate-risk grouping of patients with cervical cancer who exhibit any intermediate-risk factor after radical hysterectomy.
In total, 2158 patients with pathologically proven stage IB–IIA cervical cancer with any intermediate-risk factor after radical hysterectomy were randomly assigned to two groups, a development group and a validation group, at a ratio of 3 : 1 (1620 patients:538 patients). To predict recurrence, multivariate models were developed using the development group. The ability of the models to discriminate between groups was validated using the log-rank test and receiver operating characteristic (ROC) analysis.
Four factors (histology, tumour size, deep stromal invasion (DSI), and lymphovascular space involvement (LVSI)) were significantly associated with disease recurrence and included in the models. Among the nine possible combinations of the four variables, models consisting of any two of the four intermediate-risk factors (tumour size ⩾3 cm, DSI of the outer third of the cervix, LVSI, and adenocarcinoma or adenosquamous carcinoma histology) demonstrated the best performance for predicting recurrence.
This study identified a ‘four-factor model' in which the presence of any two factors may be useful for predicting recurrence in patients with cervical cancer treated with radical hysterectomy.
PMCID: PMC3899760  PMID: 24357798
cervical cancer; intermediate-risk group; four-factor model
13.  Tumor-reactive CD8+ T cells in metastatic gastrointestinal cancer refractory to chemotherapy 
To evaluate whether patients with metastatic gastrointestinal (GI) adenocarcinomas refractory to chemotherapy harbor tumor-reactive cytotoxic T cells.
Experimental design
Expansion of CD8+ tumor-infiltrating lymphocytes (TIL) and cancer cell lines was attempted from GI cancer metastases in 16 consecutive patients for the study of anti-tumor immune recognition. Retroviral transduction of genes encoding T-cell receptors (TCR) was used to define HLA-restriction elements and specific reactivity.
TIL were expanded from metastases in all patients, and new tumor cell lines generated in five patients. Autologous tumor-recognition without cross-reactivity against allogeneic HLA-matched GI tumors was found in CD8+ TIL from three of these five patients. In a patient with gastric cancer liver metastases, the repertoire of CD8+ TIL was dominated by cytolytic sister clones reactive to 2 out of 4 autologous cancer cell lines restricted by HLA-C*0701. From the same patient, a rare CD8+ TIL clone with a distinct TCR recognized all four cancer cell lines restricted by HLA-B*4901. In a patient with bile duct cancer, two distinct anti-tumor cytolytic clones were isolated from a highly polyclonal CD8+ TIL repertoire. TCRs isolated from these clones recognized epitopes restricted by HLA-A*0201. In a third patient, CD8+ TIL reactivity was progressively lost against an autologous colon cancer cell line that displayed loss of HLA haplotype.
This study provides a basis for the development of immunotherapy for patients with advanced GI malignancies by first establishing the presence of naturally occurring tumor-reactive CD8+ TIL at the molecular level.
PMCID: PMC3927404  PMID: 24218514
Gastrointestinal neoplasms; Metastasis; CD8-positive T-lymphocytes; Tumor-infiltrating lymphocytes; Adoptive cellular immunotherapy
14.  A Case of Oropharyngeal Bullous Pemphigoid Presenting with Haemoptysis 
Case Reports in Otolaryngology  2015;2015:631098.
Objective. Bullous pemphigoid is well known for its cutaneous features; however in rare cases it may present with mucosal involvement. We report a case of bullous pemphigoid presenting with haemoptysis, initially presenting to the Ear, Nose and Throat Department for investigation. Methods. An 87-year-old lady was admitted with haemoptysis. She also complained of a spreading, pruritic, bullous rash, which first began three weeks previously. Initial investigations, which included nasendoscopy, revealed a normal nasal mucosa and a normal postnasal space. A large deroofed blister was observed on the soft palate. The presenting symptoms and signs raised the suspicion of an immunobullous disease including bullous pemphigoid. Conclusion. Bullous pemphigoid (BP) is a subepidermal immunobullous disease that typically manifests in elderly patient populations. Although rare, BP can present in a mucocutaneous fashion akin to its more aggressive variant, mucous membrane pemphigoid (MMP). Differentiation of the two is based on clinical grounds, with the prevailing feature for the latter being the predominance of mucosal involvement, which may be extensive. The mainstay of treatment for bullous pemphigoid is steroid therapy, which may be administered both topically and systemically. A deeper understanding into the pathophysiology of the various immunobullous diseases may assist in our understanding of how the various disease entities manifest themselves.
PMCID: PMC4302357  PMID: 25632365
15.  A multifunctional protein EWS regulates the expression of Drosha and microRNAs 
Cell Death and Differentiation  2013;21(1):136-145.
EWS (Ewing's Sarcoma) gene encodes an RNA/DNA-binding protein that is ubiquitously expressed and involved in various cellular processes. EWS deficiency leads to impaired development and early senescence through unknown mechanisms. We found that EWS regulates the expression of Drosha and microRNAs (miRNAs). EWS deficiency resulted in increased expression of Drosha, a well-known microprocessor, and increased levels of miR-29b and miR-18b. Importantly, miR-29b and miR-18b were directly involved in the post-transcriptional regulation of collagen IV alpha 1 (Col4a1) and connective tissue growth factor (CTGF) in EWS knock-out (KO) mouse embryonic fibroblast cells. The upregulation of Drosha, miR-29b and miR-18b and the sequential downregulation of Col4a1 and CTGF contributed to the deregulation of dermal development in EWS KO mice. Otherwise, knockdown of Drosha rescued miRNA-dependent downregulation of Col4a1 and CTGF proteins. Taken together, our data indicate that EWS is involved in post-transcriptional regulation of Col4a1 and CTGF via a Drosha–miRNA-dependent pathway. This finding suggests that EWS has a novel role in dermal morphogenesis through the modulation of miRNA biogenesis.
PMCID: PMC3857629  PMID: 24185621
EWS; Drosha; microRNA; CTGF; dermal development
16.  Characterization of Growth, Glomerular Number, and Tubular Proteins in the Developing Rhesus Monkey Kidney 
An essential step in the translation of cell-based therapies for kidney repair involves preclinical studies in relevant animal models. Regenerative therapies in children with congenital kidney disease may provide benefit, but limited quantitative data on normal development is available to aid in identifying efficient protocols for repair. Nonhuman primates share many developmental similarities with humans and provide an important translational model for understanding nephrogenesis and morphological changes across gestation. These studies assessed monkey kidney size and weight during development and utilized stereological methods to quantitate total number of glomeruli. Immunohistochemical methods were included to identify patterns of expression of tubular proteins including Aquaporin-1 (AQP1), AQP2, Calbindin, E-Cadherin, and Uromodulin. Results have shown that glomerular number increased linearly with kidney weight, from 1.1 × 103 in the late first trimester to 3.5 × 105 near term (P < 0.001). The ratio of glomeruli to body weight tripled from the late first to early second trimester then remained relatively unchanged. Only AQP1 was expressed in the proximal tubule and descending Loop of Henle. The ascending Loop of Henle was positive for AQP2, Calbindin, and Uromodulin; distal convoluted tubules stained for Calbindin only; and collecting tubules expressed AQP2 and E-Cadherin with occasional Calbindin-positive cells. These findings provide quantitative information on normal kidney ontogeny in rhesus monkeys and further support the importance of this model for human kidney development.
PMCID: PMC4272578  PMID: 23997038
kidney; nephrogenesis; monkey; stereology; fetus
17.  Efficient Synthesis and In Vivo Incorporation of Acridon-2-ylalanine, a Fluorescent Amino Acid for Lifetime and FRET/LRET Studies 
Journal of the American Chemical Society  2013;135(50):18806-18814.
The amino acid acridon-2-ylalanine (Acd) can be a valuable probe of protein conformational change because it is a long lifetime, visible wavelength fluorophore that is small enough to be incorporated during ribosomal biosynthesis. Incorporation of Acd into proteins expressed in E. coli requires efficient chemical synthesis to produce large quantities of the amino acid and the generation of a mutant aminoacyl tRNA synthetase that can selectively charge the amino acid onto a tRNA. Here, we report the synthesis of Acd in 87 % yield over five steps from Tyr, and the identification of an Acd synthetase by screening candidate enzymes previously evolved from M. janaschii Tyr synthetase for unnatural amino acid incorporation. Furthermore, we characterize the photophysical properties of Acd, including quenching interactions with select natural amino acids and Förster resonance energy transfer (FRET) interactions with common fluorophores such as methoxycoumarin (Mcm). Finally, we demonstrate the value of incorporation of Acd into proteins, using changes in Acd fluorescence lifetimes, Mcm/Acd FRET, or energy transfer to Eu3+ to monitor protein folding and binding interactions.
PMCID: PMC4041393  PMID: 24303933
18.  Anisotropy of the superconducting gap in the iron-based superconductor BaFe2(As1-xPx)2 
Scientific Reports  2014;4:7292.
We report peculiar momentum-dependent anisotropy in the superconducting gap observed by angle-resolved photoemission spectroscopy in BaFe2(As1-xPx)2 (x = 0.30, Tc = 30 K). Strongly anisotropic gap has been found only in the electron Fermi surface while the gap on the entire hole Fermi surfaces are nearly isotropic. These results are inconsistent with horizontal nodes but are consistent with modified s± gap with nodal loops. We have shown that the complicated gap modulation can be theoretically reproduced by considering both spin and orbital fluctuations.
PMCID: PMC4252890  PMID: 25465027
19.  The impact of saddle embolism on the major adverse event rate of patients with non-high-risk pulmonary embolism 
The British Journal of Radiology  2013;86(1032):20130273.
Wider application of CT angiography (CTA) improves the diagnosis of acute pulmonary embolism (PE). It also permits the visualisation of saddle embolism (SE), namely thrombi, which are located at the bifurcation of the main pulmonary artery. The aim of this study was to assess the prevalence of SE and whether SE predicts a complicated clinical course in patients with non-high-risk PE.
In total, 297 consecutive patients with non-high-risk PE confirmed using CTA in the emergency department were studied. The presence of SE and its ability to predict the occurrence of major adverse events (MAEs) within 1 month were determined.
Of the 297 patients, 27 (9.1%) had an SE. The overall mortality at 1 month was 12.5%; no significant difference was observed between the SE and non-SE groups (18.5% vs 11.9%, p=0.32). However, patients with SE were more likely to receive thrombolytic therapy (29.6% vs 8.1%, p<0.01) and had significantly more MAEs (59.3% vs 25.6%, p<0.01).
At the time of diagnosis, SE, as determined using CTA, is associated with the development of MAE within 1 month. It may be a simple method for risk stratification of patients with non-high-risk PE.
Advances in knowledge:
The prognosis of patients with SE, especially those who are haemodynamically stable, is unclear. This study shows that patients with SE, determined with CTA, is associated with the development of MAE.
PMCID: PMC3856545  PMID: 24058095
20.  Impact of Transmammary-Delivered Meloxicam on Biomarkers of Pain and Distress in Piglets after Castration and Tail Docking 
PLoS ONE  2014;9(12):e113678.
To investigate a novel route for providing analgesia to processed piglets via transmammary drug delivery, meloxicam was administered orally to sows after farrowing. The objectives of the study were to demonstrate meloxicam transfer from sows to piglets via milk and to describe the analgesic effects in piglets after processing through assessment of pain biomarkers and infrared thermography (IRT). Ten sows received either meloxicam (30 mg/kg) (n = 5) or whey protein (placebo) (n = 5) in their daily feedings, starting four days after farrowing and continuing for three consecutive days. During this period, blood and milk samples were collected at 12-hour intervals. On Day 5 after farrowing, three boars and three gilts from each litter were castrated or sham castrated, tail docked, and administered an iron injection. Piglet blood samples were collected immediately before processing and at predetermined times over an 84-hour period. IRT images were captured at each piglet blood collection point. Plasma was tested to confirm meloxicam concentrations using a validated high-performance liquid chromatography-mass spectrometry method. Meloxicam was detected in all piglets nursing on medicated sows at each time point, and the mean (± standard error of the mean) meloxicam concentration at castration was 568.9±105.8 ng/mL. Furthermore, ex-vivo prostaglandin E2 (PGE2) synthesis inhibition was greater in piglets from treated sows compared to controls (p = 0.0059). There was a time-by-treatment interaction for plasma cortisol (p = 0.0009), with meloxicam-treated piglets demonstrating lower cortisol concentrations than control piglets for 10 hours after castration. No differences in mean plasma substance P concentrations between treatment groups were observed (p = 0.67). Lower cranial skin temperatures on IRT were observed in placebo compared to meloxicam-treated piglets (p = 0.015). This study demonstrates the successful transfer of meloxicam from sows to piglets through milk and corresponding analgesia after processing, as evidenced by a decrease in cortisol and PGE2 levels and maintenance of cranial skin temperature.
PMCID: PMC4249978  PMID: 25437866
21.  TWIK-1 contributes to the intrinsic excitability of dentate granule cells in mouse hippocampus 
Molecular Brain  2014;7(1):80.
Two-pore domain K+ (K2P) channels have been shown to modulate neuronal excitability. However, physiological function of TWIK-1, the first identified member of the mammalian K2P channel family, in neuronal cells is largely unknown.
We found that TWIK-1 proteins were expressed and localized mainly in the soma and proximal dendrites of dentate gyrus granule cells (DGGCs) rather than in distal dendrites or mossy fibers. Gene silencing demonstrates that the outwardly rectifying K+ current density was reduced in TWIK-1-deficient granule cells. TWIK-1 deficiency caused a depolarizing shift in the resting membrane potential (RMP) of DGGCs and enhanced their firing rate in response to depolarizing current injections. Through perforant path stimulation, TWIK-1-deficient granule cells showed altered signal input-output properties with larger EPSP amplitude values and increased spiking compared to control DGGCs. In addition, supra-maximal perforant path stimulation evoked a graded burst discharge in 44% of TWIK-1-deficient cells, which implies impairment of EPSP-spike coupling.
These results showed that TWIK-1 is functionally expressed in DGGCs and contributes to the intrinsic excitability of these cells. The TWIK-1 channel is involved in establishing the RMP of DGGCs; it attenuates sub-threshold depolarization of the cells during neuronal activity, and contributes to EPSP-spike coupling in perforant path-to-granule cell synaptic transmission.
Electronic supplementary material
The online version of this article (doi:10.1186/s13041-014-0080-z) contains supplementary material, which is available to authorized users.
PMCID: PMC4240835  PMID: 25406588
K2P channel; TWIK-1; Intrinsic excitability; Dentate gyrus granule cell
22.  Radiolabeling and In Vivo Imaging of Transplanted Renal Lineages Differentiated from Human Embryonic Stem Cells in Fetal Rhesus Monkeys 
The goals of this study were to optimize radiolabeling of renal lineages differentiated from human embryonic stem (hES) cells and use noninvasive imaging (positron emission tomography (PET) and bioluminescence imaging (BLI)) to detect the cells in fetal monkeys post-transplant.
hES cells expressing firefly luciferase (5×106) were radiolabeled with the optimized concentration of 10 μCi/ml 64Cu-PTSM then transplanted under ultrasound guidance into early second trimester fetal monkey kidneys. Fetuses were imaged in utero with PET and tissues collected for analysis 3 days post-transplant. Fetal kidneys were imaged ex vivo (PET and BLI) post-tissue harvest, and serial kidney sections were assessed by PCR for human-specific DNA sequences, fluorescent in situ hybridization (FISH) for human-specific centromere probes, and immunohistochemistry (IHC) to assess engrafted cells.
Transplanted cells were readily imaged in vivo and identified at the site of injection; tissue analyses confirmed the imaging findings. Using a semi-quantitative method, one in approximately 650 cells in the kidney was shown to be of human origin by PCR and FISH.
These studies suggest that hES cells differentiated toward renal lineages can be effectively radiolabeled, transplanted into fetal monkey kidneys under ultrasound guidance, monitored with PET post-transplant, and identified by PET, BLI, PCR, FISH, and IHC post-tissue harvest.
PMCID: PMC4224287  PMID: 21479709
PET; Bioluminescence imaging; Human embryonic stem cells; Fetal transplant; Rhesus monkey
23.  Quantification of Cell-Associated Atazanavir, Darunavir, Lopinavir, Ritonavir, and Efavirenz Concentrations in Human Mononuclear Cell Extracts 
An ultrasensitive assay utilizing high-pressure liquid chromatography and mass spectrometry detection was developed and validated for the quantification of the antiretrovirals atazanavir (ATV), darunavir (DRV), lopinavir (LPV), ritonavir (RTV), and efavirenz (EFV) in human mononuclear cell (MNC) extracts. The assay utilizes 20 μl of cellular extract that contains as few as 50,000 MNCs. The analytical range of the assay is 0.0200 to 10.0 fmol/μl for ATV, 0.0500 to 25.0 fmol/μl for DRV, LPV, and RTV, and 0.200 to 100 fmol/μl for EFV. The assay has proven to be a clinically useful tool for investigating antiretroviral drug concentrations in virologic sanctuaries where harvested cell numbers are extremely low. The assay provides a tool for investigators to explore the clinical pharmacology of strategies for prevention, treatment, and cure in pathophysiologically relevant sites.
PMCID: PMC3993270  PMID: 24614370
24.  Clinical-guide risk prediction of hepatocellular carcinoma development in chronic hepatitis C patients after interferon-based therapy 
British Journal of Cancer  2013;109(9):2481-2488.
Interferon (IFN)-based therapies could eradicate hepatitis C (HCV) and reduce the risk of hepatocellular carcinoma (HCC). However, HCC could still happen after sustained virological response (SVR). We aimed to develop a simple scoring system to predict the risk of HCC development among HCV patients after antiviral therapies.
From 1999 to 2009, 1879 patients with biopsy-proven HCV infection treated with IFN-based therapies were analyzed.
Multivariable analysis showed old age (adjusted HR (aHR)=1.73, 95% CI=1.13–2.65 for aged 60–69 and aHR=2.20, 95% CI=1.43–3.37 for aged ⩾70), Male gender (aHR=1.74, 95% CI=1.26–2.41), platelet count <150 × 109/l (HR=1.91, 95% CI=1.27–2.86), α-fetoprotein ⩾20 ng ml−1 (HR=2.23, 95% CI=1.58–3.14), high fibrotic stage (HR=3.32, 95% CI=2.10–5.22), HCV genotype 1b (HR=1.53, 95% CI=1.10–2.14), and non SVR (HR=2.40, 95% CI=1.70–3.38) were independent risk factors for HCC. Regression coefficients were used to build up a risk score and the accuracy was evaluated by using the area under the receiver operating characteristic curve (AUC). Three groups as low-, intermediate-, and high-risk are classified based on the risk scores. One hundred sixty patients (12.78%) in the derivation and 82 patients (13.08%) in the validation cohort developed HCC with AUC of 79.4%, sensitivity of 84.38%, and specificity of 60.66%. In the validation cohort, the 5-year HCC incidence was 1.81%, 12.92%, and 29.95% in low-, intermediate-, and high-risk groups, with hazard ratios 4.49 in intermediate- and 16.14 in high-risk group respectively. The risk reduction of HCC is greatest in patients with SVR, with a 5-year and 10-year risk reduction of 28.91% and 27.99% respectively.
The risk scoring system is accurate in predicting HCC development for HCV patients after antiviral therapies.
PMCID: PMC3817320  PMID: 24084770
risk score; hepatitis C virus; interferon; hepatocellular carcinoma
25.  Role of aldehydes in the toxic and mutagenic effects of nitrosamines 
Chemical research in toxicology  2013;26(10):10.1021/tx400196j.
α-Hydroxynitrosamine metabolites of nitrosamines decompose to a reactive diazohydroxide and an aldehyde. To test the hypothesis that the aldehydes contribute to the harmful effects of nitrosamines, the toxic and mutagenic activity of three model methylating agents were compared in Chinese hamster ovary cells expressing human O6-alkylguanine DNA alkyltransferase (AGT) or not. N-Nitrosomethylurethane (NMUr), acetoxymethylmethylnitrosamine (AMMN) and 4-(methylnitrosamino)-4-acetoxy-1-(3-pyridyl)-1-butanone (NNK-4-OAc) are all activated by ester hydrolysis to methanediazohydroxide. NMUr does not form an aldehyde whereas AMMN generates formaldehyde and NNK-4-OAc produces 4-oxo-1-(3-pyridyl)-1-butanone (OPB). Since these compounds were likely to alkylate DNA to different extents, the toxic and mutagenic activity of these compounds was normalized to the levels of the most cytotoxic and mutagenic DNA adduct, O6-mG, to assess if the aldehydes contributed to the toxicological properties of these methylating agents. Levels of 7-mG indicated that the differences in cytotoxic and mutagenic effects of these compounds resulted from differences in their ability to methylate DNA. When normalized against the levels of O6-mG, there was no difference between these three compounds in cells that lacked AGT. However, AMMN and NNK-4-OAc were more toxic than NMUr in cells expressing AGT when normalized against O6-mG levels. In addition, AMMN was more mutagenic than NNK-4-OAc and MNUr in these cells. These findings demonstrate that the aldehyde decomposition products of nitrosamines can contribute to the cytotoxic and/or mutagenic activity of methylating nitrosamines.
PMCID: PMC3835663  PMID: 24066836
nitrosamines; aldehyde; mutagenicity; toxicity; DNA repair

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