Vitamin D and vitamin D dependency

Administration of large doses of vitamin D2 brought about a marked increase of 25-hydroxyvitamin D in both the patients with vitamin D dependency and hypophosphatemic vitamin D-resistant rickets. During the administration of vitamin D2, increment of 1,25-dihydroxyvitamin D was marked in hypophosphatemic vitamin D-resistant rickets, but far smaller in vitamin D dependency. In the latter, however, the 1,25-dihydroxyvitamin D reached the level close to the normal adult values. 1 alpha-hydroxyvitamin D3 was found 50 approximately 100 times as effective as vitamin D2 in 2 patients with vitamin D dependency (optimum maintenance dose: 0.05 micrograms/kg/day). It was concluded that 1 alpha-hydroxylation in the renal tubules is markedly defective in the patients with vitamin D dependency, but that a large dose of vitamin D2 is able to cause a definite increase in serum concentration of 1,25-dihydroxyvitamin D resulting in improvement of the rickets.

Robust MR assessment of cerebral blood volume and mean vessel size using SPION-enhanced ultrashort echo acquisition

Intravascular superparamagnetic iron oxide nanoparticles (SPION)-enhanced MR transverse relaxation rates (∆R2(⁎) and ∆R2) are widely used to investigate in vivo vascular parameters, such as the cerebral blood volume (CBV), microvascular volume (MVV), and mean vessel size index (mVSI, ∆R2(⁎)/∆R2). Although highly efficient, regional comparison of vascular parameters acquired using gradient-echo based ∆R2(⁎) is hampered by its high sensitivity to magnetic field perturbations arising from air-tissue interfaces and large vessels. To minimize such demerits, we took advantage of the dual contrast property of SPION and both theoretically and experimentally verified the direct benefit of replacing gradient-echo based ∆R2(⁎) measurement with ultra-short echo time (UTE)-based ∆R1 contrast to generate the robust CBV and mVSI maps. The UTE acquisition minimized the local measurement errors from susceptibility perturbations and enabled dose-independent CBV measurement using the vessel/tissue ∆R1 ratio, while independent spin-echo acquisition enabled simultaneous ∆R2 measurement and mVSI calculation of the cortex, cerebellum, and olfactory bulb, which are animal brain regions typified by significant susceptibility-associated measurement errors.

A New Statistical Model Identified Two-thirds of Clinical T1 Gastric Cancers as Possible Candidates for Endoscopic Treatment

BACKGROUND

Clinical T1 gastric cancer has low metastatic potential to lymph nodes and is generally curable by local treatment. Endoscopic resection can preserve the whole stomach and does not impair the patient's quality of life; however, its indication is strictly limited to the subset of patients without nodal metastasis. The study was designed to predict reliably the patients without nodal metastasis based only on the clinical information.

METHODS

We examined patients with clinical T1 disease who were treated with surgery. The clinically available information was evaluated for its ability to predict nodal metastasis by logistic regression model. Then, the predictive ability of the logistic regression model using the risk factors for nodal metastasis was evaluated by a receiver operating characteristic curve.

RESULTS

A total of 511 patients were entered into this study. The clinical depth (cT1a or cT1b), maximal tumor diameter, and pathological type were confirmed to be significantly different between patients with and without nodal metastasis. The cutoff value of the tumor diameter differed depending on the histology and clinical depth: 79 mm for differentiated type and 48 mm for undifferentiated type in cT1a tumors, and 43 mm for differentiated type and 11 mm for undifferentiated type in cT1b tumors. According to these criteria, 348 of the 511 patients (68.1 %) were classified to have predictive N0 status. The negative predictive value was 95.7 % (95 % confidence interval 94.0-97.5 %).

CONCLUSIONS

The predictive criteria based on the multivariate logistic model identified that almost two-thirds of the patients with clinical T1 gastric cancer were possible candidates for endoscopic treatment.

Optimal sampling with prior information of the image geometry in microfluidic MRI

Recent advances in MRI acquisition for microscopic flows enable unprecedented sensitivity and speed in a portable NMR/MRI microfluidic analysis platform. However, the application of MRI to microfluidics usually suffers from prolonged acquisition times owing to the combination of the required high resolution and wide field of view necessary to resolve details within microfluidic channels. When prior knowledge of the image geometry is available as a binarized image, such as for microfluidic MRI, it is possible to reduce sampling requirements by incorporating this information into the reconstruction algorithm. The current approach to the design of the partial weighted random sampling schemes is to bias toward the high signal energy portions of the binarized image geometry after Fourier transformation (i.e. in its k-space representation). Although this sampling prescription is frequently effective, it can be far from optimal in certain limiting cases, such as for a 1D channel, or more generally yield inefficient sampling schemes at low degrees of sub-sampling. This work explores the tradeoff between signal acquisition and incoherent sampling on image reconstruction quality given prior knowledge of the image geometry for weighted random sampling schemes, finding that optimal distribution is not robustly determined by maximizing the acquired signal but from interpreting its marginal change with respect to the sub-sampling rate. We develop a corresponding sampling design methodology that deterministically yields a near optimal sampling distribution for image reconstructions incorporating knowledge of the image geometry. The technique robustly identifies optimal weighted random sampling schemes and provides improved reconstruction fidelity for multiple 1D and 2D images, when compared to prior techniques for sampling optimization given knowledge of the image geometry.

204 A COMPARATIVE ANALYSIS OF CALCIUM TRANSPORT GENES EXPRESSION IN HOLSTEIN AND HANWOO (KOREAN CATTLE) IN THE DUODENUM AND KIDNEY

Transmembranous calcium (Ca2+) channels such as Trpv5/6,Ncx1,Pmca1b are known to play an important role in maintaining homeostasis and metabolizing Ca2+ ions. Transient receptor potential cation channel subfamily V members 5 and 6 (Trpv5/6) play an important role in Ca2+ absorption. Na+/Ca2+ exchanger 1 (Ncx1) and plasma membrane Ca2+-transporting ATPase1 (Pmca1b) play a role in Ca2+ excretion. Holstein cattle are known to provide higher milk production than other cattle breeds. In this respect, a higher susceptibility to hypocalcaemia that is a risk factor for many of calcium-related diseases such as milk fever has been observed. In contrary, Hanwoo cattle are relatively resistant to the calcium-related diseases. The aim of this study was to evaluate the expression of calcium transport genes in the duodenum and kidney of Hanwoo (Korean cattle) and Holstein cattle. All samples were obtained from Holstein and Hanwoo cattle from 36 to 60 months of age at a local slaughterhouse. The collected duodenum and kidney were rapidly excised and washed in cold sterile saline (0.9% NaCl). Total RNA was prepared from duodenum and kidney tissues using TRIzol Reagent (Invitrogen, Carlsbad, CA, USA), according to the manufacturer's protocol. Protein was extracted using Pro-prep (iNtRON Bio), according to the manufacturer's protocol. Expression of Trpv5/6, Ncx1 and Pmca1b was analysed by real-time RT–PCR, Western blot analysis, and immunohistochemistry. In dairy cattle's kidney (Holstein), the level of Trpv5 mRNA was ~3-fold more than Hanwoo's kidney while Pmca1b mRNA was one-fifth less than Hanwoo's kidney. However, no difference in Trpv6 and Ncx1 mRNA expression was observed in the kidney of Holstein compared with Hanwoo. Duodenal Trpv5 and Trpv6 mRNA were scarcely expressed in both Hanwoo and Holstein cattle. In addition, the mRNA expression of Pmca1b and Ncx1 were also not different between Hanwoo and Holstein. The protein expression of calcium transport genes were similar to the mRNA levels of calcium transport genes in both Hanwoo and Holstein. Localization of calcium transporter genes were identified, the glomerulus, and proximal and distal convoluted tubules expressed TRPV5, 6, Pmca1b, and Ncx1 in the kidney. These four calcium transport genes may play an important role in the bovine duodenum and kidney. The difference between Holstein and Hanwoo animals which express different gene expression patterns may be helpful in studying diseases associated with calcium metabolism, e.g. milk fever.

Plasmaphresis therapy for pulmonary hemorrhage in a pediatric patient with IgA nephropathy

IgA nephropathy usually presents as asymptomatic microscopic hematuria or proteinuria or episodic gross hematuria after upper respiratory infection. It is an uncommon cause of end-stage renal failure in childhood. Pulmonary hemorrhage associated with IgA nephropathy is an unusual life-threatening manifestation in pediatric patients and is usually treated with aggressive immunosuppression. Pulmonary hemorrhage and renal failure usually occur concurrently, and the pulmonary manifestation is believed to be caused by the same immune process. We present the case of a 14-year-old patient with IgA nephropathy who had already progressed to end-stage renal failure in spite of immunosuppression and presented with pulmonary hemorrhage during oral prednisone treatment. His lung disease was comparable to diffuse alveolar hemorrhage and was successfully treated with plasmapheresis followed by oral prednisone. This case suggests that pulmonary hemorrhage may develop independently of renal manifestation, and that plasmapheresis should be considered as adjunctive therapy to immunosuppressive medication for treating IgA nephropathy with pulmonary hemorrhage.

Thiocoraline activates the Notch pathway in carcinoids and reduces tumor progression in vivo

Carcinoids are slow-growing neuroendocrine tumors (NETs) that are characterized by hormone overproduction; surgery is currently the only option for treatment. Activation of the Notch pathway has previously been shown to have a role in tumor suppression in NETs. The marine-derived thiodepsipeptide thiocoraline was investigated in vitro in two carcinoid cell lines (BON and H727). Carcinoid cells treated with nanomolar concentrations of thiocoraline resulted in a decrease in cell proliferation and an alteration of malignant phenotype evidenced by decrease of NET markers, ASCL-1, CgA, and NSE. Western blot analysis demonstrated the activation of Notch1 on the protein level in BON cells. Additionally, thiocoraline activated downstream Notch targets HES1, HES5, and HEY2. Thiocoraline effectively suppressed carcinoid cell growth by promoting cell cycle arrest in BON and H727 cells. An in vivo study demonstrated that thiocoraline, formulated with polymeric micelles, slowed carcinoid tumor progression. Thus, the therapeutic potential of thiocoraline, which induced activation of the Notch pathway, in carcinoid tumors was demonstrated.

Development of inorganic and organic hybrid nanocoating based on carbon nanotubes for corrosion resistance

In this study, we report the synthesis and characterization of novel hybrid nanocoating based on carbon nanotubes (CNTs) on anodized aluminum surfaces (AAO). The hybrid nanocoating was deposited by number of methods which include spray coating, spin coating and dip coating. The bonding of nanocoating with metal surface is an important parameter for successful modification of the metal surfaces. The improved adhesion of nanocoating on metal surfaces could be attributed to chemical bonding of sol-gel nanocoating with anodized surfaces. The nanocoated anodized aluminum surfaces showed superior adhesion and excellent anticorrosive properties. The nanocoated panels showed enhanced galvanic protection comparable to 80% of titanium metal as determined by galvanic corrosion measurements. It also showed higher thermal conductivities than stainless steel and bare anodized surfaces.

Elastic differential cross sections for C₄F₆ isomers in the 1.5-200 eV energy electron impact: similarities with six fluorine containing molecules and evidence of F-atom like scattering

We report absolute elastic differential cross sections for electron interactions with the C4F6 isomers, hexafluoro-1,3-butadiene (1,3-C4F6), hexafluoro-2-butyne (2-C4F6), and hexafluorocyclobutene (c-C4F6). The incident electron energy range is 1.5-200 eV, and the scattered electron angular range for the differential measurements varies from 15° to 150°. In all cases the absolute scale of the differential cross section was set using the relative flow technique, with helium as the reference species. Atomic-like behaviour in these scattering systems is shown here for the first time, and is further investigated by comparing the elastic cross sections for the C4F6 isomers with other fluorinated molecules, such as SF6 and CnF6 (n = 2, 3, and 6). We note that for all the six-F containing molecules, the scattering process for electron energies above 30 eV is indistinguishable. Finally, we report results for calculations of elastic differential cross sections for electron scattering from each of these isomers, within an optical potential method and assuming a screened corrected independent atom representation. The level of agreement between these calculations and our measurements is found to be quite remarkable in all cases.

Prioritization of the introduction of new vaccines to the national immunization program in the Republic of Korea

BACKGROUND

This study was performed to determine the priority of vaccine introduction for five vaccine-preventable diseases (VPDs) caused by Haemophilus influenzae type b (Hib), pneumococcus (Spn), hepatitis A virus (HepA), rotavirus (RV), and human papillomavirus (HPV) to the future Korean National Immunization Program (NIP) and to suggest framework programs to assist decision makers on implementation of the NIP.

METHODS

Following analysis of the disease burden and economics of the five VPDs by the core team and Korean Advisory Committee on Immunization Practices sub-committee members, a Delphi survey was administered to 94 Korean experts using structured questionnaires that provided the reference data. The two evaluation frameworks for NIP prioritization were (1) a disease-related framework and (2) a vaccine-related framework. After analyzing the responses, a meeting of experts was held to build a consensus for determining how to prioritize NIP implementation.

RESULTS

The average scores for relative importance were 63.29 for the disease-related framework and 36.71 for the vaccine-related framework. Within the disease-related framework, the mortality and case fatality rate was the highest scored factor (8.97), whereas within the vaccine-related framework, efficacy of the vaccine was considered the most important factor (9.56). On average, Spn, Hib, and HepA had the highest priority scores.

CONCLUSION

The Korean experts suggested that the main factors influencing the decision to adopt new vaccines in the Korean NIP should be disease mortality, case fatality, and the efficacy and effectiveness of the vaccine. Among the five selected VPDs, Spn, Hib, and HepA were considered to be of higher priority than RV and HPV.

Ultrafast 3D spin-echo acquisition improves Gadolinium-enhanced MRI signal contrast enhancement

Long scan times of 3D volumetric MR acquisitions usually necessitate ultrafast in vivo gradient-echo acquisitions, which are intrinsically susceptible to magnetic field inhomogeneities. This is especially problematic for contrast-enhanced (CE)-MRI applications, where non-negligible T₂* effect of contrast agent deteriorates the positive signal contrast and limits the available range of MR acquisition parameters and injection doses. To overcome these shortcomings without degrading temporal resolution, ultrafast spin-echo acquisitions were implemented. Specifically, a multiplicative acceleration factor from multiple spin echoes (×32) and compressed sensing (CS) sampling (×8) allowed highly-accelerated 3D Multiple-Modulation-Multiple-Echo (MMME) acquisition. At the same time, the CE-MRI of kidney with Gd-DOTA showed significantly improved signal enhancement for CS-MMME acquisitions (×7) over that of corresponding FLASH acquisitions (×2). Increased positive contrast enhancement and highly accelerated acquisition of extended volume with reduced RF irradiations will be beneficial for oncological and nephrological applications, in which the accurate in vivo 3D quantification of contrast agent concentration is necessary with high temporal resolution.

MARCH5-mediated quality control on acetylated Mfn1 facilitates mitochondrial homeostasis and cell survival

Mitochondrial dynamics and quality control have a central role in the maintenance of cellular integrity. Mitochondrial ubiquitin ligase membrane-associated RING-CH (MARCH5) regulates mitochondrial dynamics. Here, we show that mitochondrial adaptation to stress is driven by MARCH5-dependent quality control on acetylated Mfn1. Under mitochondrial stress conditions, levels of Mfn1 were elevated twofold and depletion of Mfn1 sensitized these cells to apoptotic death. Interestingly, overexpression of Mfn1 also promoted cell death in these cells, indicating that a fine tuning of Mfn1 levels is necessary for cell survival. MARCH5 binds Mfn1 and the MARCH5-dependent Mfn1 ubiquitylation was significantly elevated under mitochondrial stress conditions along with an increase in acetylated Mfn1. The acetylation-deficient K491R mutant of Mfn1 showed weak interaction with MARCH5 as well as reduced ubiquitylation. Neither was observed in the acetylation mimetic K491Q mutant. In addition, MARCH5-knockout mouse embryonic fibroblast and MARCH5(H43W)-expressing HeLa cells lacking ubiquitin ligase activity experienced rapid cell death upon mitochondrial stress. Taken together, a fine balance of Mfn1 levels is maintained by MARCH5-mediated quality control on acetylated Mfn1, which is crucial for cell survival under mitochondria stress conditions.

Diagnostic value of computed tomography for staging of clinical T1 gastric cancer

BACKGROUND

T1 gastric cancer can be diagnosed only by endoscopy and is almost curable by local treatment. It has been unclear how a multidetector-row computed tomography (CT) evaluation is valuable for clinical T1 patients.

METHODS

Patients with clinical T1 disease, as diagnosed by endoscopy and treated with endoscopic submucosal dissection (ESD) or surgery between October 2000 and October 2007, were examined. The efficacy of CT was evaluated by the reversal rate of endoscopic T1 by CT, the incidence of clinical M1 disease, and the accuracy of diagnosing pathological N+ disease in patients who received surgery. To confirm metachronous distant and nodal metastases, the disease-free survival (DFS) also was evaluated.

RESULTS

A total of 761 patients, 236 treated by ESD and 525 treated with surgery, were examined. None of the patients had an endoscopic diagnosis of clinical T1 reversed by CT. No clinical M1 disease was found. Among the 525 patients who underwent surgery, 8 showed clinical N+ disease (1.5 %), while 47 demonstrated pathological N+ disease (8.9 %). The accuracy, sensitivity, specificity, positive predictive value, and negative predictive values were 90.3, 4.3, 98.7, 25, and 91.3 %, respectively. The 5-year DFS rate was 93.6 % (95 % confidence interval 91.4-95.8 %).

CONCLUSIONS

The present study suggests that diagnostic value of CT is limited for staging of clinical T1 gastric cancer patients, because the reversal rate of endoscopic T1 by CT was very low, clinical M1 disease was rare, the diagnosis of N+ status was unreliable, and metachronous M1 and N+ findings were rare.

Cortical thickness and hippocampal shape in pure vascular mild cognitive impairment and dementia of subcortical type

BACKGROUND AND PURPOSE

The progression pattern of brain structural changes in patients with isolated cerebrovascular disease (CVD) remains unclear. To investigate the role of isolated CVD in cognitive impairment patients, patterns of cortical thinning and hippocampal atrophy in pure subcortical vascular mild cognitive impairment (svMCI) and pure subcortical vascular dementia (SVaD) patients were characterized.

METHODS

Forty-five patients with svMCI and 46 patients with SVaD who were negative on Pittsburgh compound B (PiB) positron emission tomography imaging and 75 individuals with normal cognition (NC) were recruited.

RESULTS

Compared with NC, patients with PiB(-) svMCI exhibited frontal, language and retrieval type memory dysfunctions, which in patients with PiB(-) SVaD were further impaired and accompanied by visuospatial and recognition memory dysfunctions. Compared with NC, patients with PiB(-) svMCI exhibited cortical thinning in the frontal, perisylvian, basal temporal and posterior cingulate regions. This atrophy was more prominent and extended further toward the lateral parietal and medial temporal regions in patients with PiB(-) SVaD. Compared with NC subjects, patients with PiB(-) svMCI exhibited hippocampal shape deformities in the lateral body, whilst patients with PiB(-) SVaD exhibited additional deformities within the lateral head and inferior body.

CONCLUSIONS

Our findings suggest that patients with CVD in the absence of Alzheimer's disease pathology can be demented, showing cognitive impairment in multiple domains, which is consistent with the topography of cortical thinning and hippocampal shape deformity.

Erythritol alters microstructure and metabolomic profiles of biofilm composed of Streptococcus gordonii and Porphyromonas gingivalis

The effects of sugar alcohols such as erythritol, xylitol, and sorbitol on periodontopathic biofilm are poorly understood, though they have often been reported to be non-cariogenic sweeteners. In the present study, we evaluated the efficacy of sugar alcohols for inhibiting periodontopathic biofilm formation using a heterotypic biofilm model composed of an oral inhabitant Streptococcus gordonii and a periodontal pathogen Porphyromonas gingivalis. Confocal microscopic observations showed that the most effective reagent to reduce P. gingivalis accumulation onto an S. gordonii substratum was erythritol, as compared with xylitol and sorbitol. In addition, erythritol moderately suppressed S. gordonii monotypic biofilm formation. To examine the inhibitory effects of erythritol, we analyzed the metabolomic profiles of erythritol-treated P. gingivalis and S. gordonii cells. Metabolome analyses using capillary electrophoresis time-of-flight mass spectrometry revealed that a number of nucleic intermediates and constituents of the extracellular matrix, such as nucleotide sugars, were decreased by erythritol in a dose-dependent manner. Next, comparative analyses of metabolites of erythritol- and sorbitol-treated cells were performed using both organisms to determine the erythritol-specific effects. In P. gingivalis, all detected dipeptides, including Glu-Glu, Ser-Glu, Tyr-Glu, Ala-Ala and Thr-Asp, were significantly decreased by erythritol, whereas they tended to be increased by sorbitol. Meanwhile, sorbitol promoted trehalose 6-phosphate accumulation in S. gordonii cells. These results suggest that erythritol has inhibitory effects on dual species biofilm development via several pathways, including suppression of growth resulting from DNA and RNA depletion, attenuated extracellular matrix production, and alterations of dipeptide acquisition and amino acid metabolism.