Sphingosine 1-phosphate stimulates tyrosine phosphorylation of focal adhesion kinase and chemotactic motility of endothelial cells via the G(i) protein-linked phospholipase C pathway

We have previously shown that sphingosine 1-phosphate (S1P) stimulates motility of human umbilical vein endothelial cells (HUVECs) (O.-H. Lee et al., Biochem. Biophys. Res. Commun. 264, 743-750, 1999). To investigate the molecular mechanisms by which S1P stimulates HUVEC motility, we examined tyrosine phosphorylation of p125 focal adhesion kinase (p125(FAK)) which is important for cell migration. S1P induces a rapid increase in tyrosine phosphorylation of p125(FAK). Compared with other structurally related lipid metabolites such as sphingosine, C2-ceramide, and lysophosphatidic acid, S1P uniquely stimulated p125(FAK) tyrosine phosphorylation and migration of HUVECs. The effect of S1P on p125(FAK) tyrosine phosphorylation was markedly reduced by treatment with pertussis toxin or U73122, a phospholipase C (PLC) inhibitor. As a downstream signal of PLC, p125(FAK) tyrosine phosphorylation in response to S1P was totally blocked by depletion of the intracellular calcium pool. However, protein kinase C (PKC) inhibitor had no effect on the response to S1P. Finally, chemotaxis assays revealed that inhibition of PLC but not PKC significantly abrogated S1P-stimulated HUVEC migration. These results suggest that the G(i)-coupled receptor-mediated PLC-Ca(2+) signaling pathway may be importantly involved in S1P-stimulated focal adhesion formation and migration of endothelial cells.

Interaction between IL13 genotype and environmental factors in the risk for allergic rhinitis in Korean children

BACKGROUND

The prevalence of allergic rhinitis (AR) is increasing worldwide. Allergic diseases develop in susceptible subjects when they are exposed to specific environmental factors.

OBJECTIVE

We analyzed changes in the prevalence of AR and identified genetic and environmental factors in early childhood that affect risk.

METHODS

We used the International Study of Asthma and Allergies in Childhood questionnaire to collect data on AR, allergies, and environmental exposures from 4554 elementary school students from 5 areas of Seoul, Korea, in 2008. We also obtained DNA from 1050 subjects from 1 area of Seoul for genotype analysis of IL13.

RESULTS

We identified genetic and environmental factors during infancy and early childhood that increased the risk for current AR (resulting in a diagnosis of AR and AR symptoms in the past 12 months) in elementary school-aged children. These included allergic disease in parents and antibiotic use in infants, allergic disease in parents and exposure of infants to mold, and allergic disease in parents and moving an infant to a newly built house. The risk of current AR also increased in subjects with GA or AA at nucleotide 2044 in IL13 who had been exposed to mold in the home during infancy (adjusted odds ratio, 3.27; 95% CI, 1.75-6.11) compared with subjects who had GG at this position and had not been exposed to mold (adjusted odds ratio, 3.27; 95% CI, 1.75-6.11).

CONCLUSION

The prevalence of AR is increasing in Korean children. Children with a family history of allergic disease and exposure to specific environmental risk factors during infancy are more likely to have AR. Children with GA or AA at IL13(+2044) are at increased risk for AR when exposed to mold in the home during the first year of life.

Solid pseudopapillary carcinoma of the pancreas: differentiation from benign solid pseudopapillary tumour using CT and MRI

AIM

To describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings that differentiate solid pseudopapillary carcinomas (SPC) from benign solid pseudopapillary tumours (SPT) of the pancreas.

MATERIALS AND METHODS

Preoperative CT or MRI images for 26 patients (eight patients with SPC and 18 patients with SPT) were retrospectively reviewed. In addition to the general morphological features, the presence of pancreatic duct dilation, vascular invasion, and extrapancreatic metastases were comparatively assessed.

RESULTS

There were no significant differences between pancreatic SPC and benign SPT with respect to tumour size, location, capsule thickness, internal composition, and pattern of calcification, nor was there any correlation with the age and gender of the patients. Pancreatic duct dilation was present in four of the eight (50%) SPC patients, and was absent in all benign SPT patients (p=0.005). Vascular encasement by the tumour (n=2) and hepatic metastases (n=2) were also exclusively demonstrated in SPC patients. Multivariate logistic regression analysis showed that pancreatic duct dilation (p=0.001), vessel encasement (p=0.027), and metastasis (p=0.027) were the variables that can be used to differentiate SPC from benign SPT.

CONCLUSION

SPC of the pancreas may help to differentiate from benign SPT using the imaging features of aggressive behaviour of pancreatic duct dilation and vessel encasement with or without extrapancreatic metastases.

Observer variability in RECIST-based tumour burden measurements: a meta-analysis

BACKGROUND

Response Evaluation Criteria in Solid Tumours (RECIST)-based tumour burden measurements involve observer variability, the extent of which ought to be determined.

METHODS

A literature search identified studies on observer variability during manual measurements of tumour burdens via computed tomography according to the RECIST guideline. The 95% limit of agreement (LOA) values of relative measurement difference (RMD) were pooled using a random-effects model.

RESULTS

Twelve studies were included. Pooled 95% LOAs of RMD in measuring unidimensional longest diameters of single lesions ranged from -22.1% (95% confidence interval [CI], -30.3% to -14.0%) to 25.4% (95% CI, 17.2% to 33.5%) between observers and -17.8% (95% CI, -23.6% to -11.9%) to 16.1% (95% CI, 10.1% to 21.8%) for a single observer. Pooled 95% LOAs of RMD in measuring the sum of multiple lesions ranged from -19.2% (95% CI, -23.7% to -14.9%) to 19.5% (95% CI, 15.2% to 23.9%) between observers, and -9.8% (95% CI, -19.0% to -0.3%) to 13.1% (95% CI, 3.6% to 22.6%) for a single observer. Pooled 95% LOA of RMD in calculating the interval change of tumour burden with a single lesion ranged from -31.3% (95% CI, -46.0% to -16.5%) to 30.3% (95% CI, 15.3% to 44.8%) between observers. Studies on calculating the interval change of tumour burden for a single observer or with multiple lesions were lacking.

CONCLUSION

Interobserver RMD in measuring single tumour burden and calculating its interval change may exceed the 20% cut-off for progression. Variability decreased when tumour burden was measured by a single observer or assessed by the sum of multiple lesions.

The effects of dexamethasone on insulin release and biosynthesis are dependent on the dose and duration of treatment

Complex results concerning the effect of glucocorticoids on insulin secretion have been reported. The aim of this study is to clarify the direct effects of glucocorticoids on pancreatic islets and to determine whether the effect of glucocorticoids on insulin biosynthesis or release is dependent on the dose and duration of treatment with glucocorticoid. Studies on insulin secretion and biosynthesis were performed with different concentrations (0, 1, 10, 100 nmol/l) and durations (1 and 6 h) of treatment with dexamethasone (dexa) in rat pancreatic islets. (1) One nmol/l dexa had no inhibitory effect on insulin secretion and biosynthesis. Ten and 100 nmol/l had an inhibitory effect on insulin secretion, which was mainly due to suppression of the first phase of insulin secretion. (2) Insulin content was significantly increased regardless of the concentration in 1-h treated islets. However, insulin content was markedly diminished with 100 nmol/l dexa in 6-h treated islets. (3) The preproinsulin mRNA expression of 6-h treated islets was suppressed in a dose-dependent manner. Our data revealed that, in the condition of short-term and low-dose glucocorticoid exposure, insulin secretion and biosynthesis are not affected. The secretory process of insulin seems to be the initial step of the inhibitory action of glucocorticoid. Both insulin release and biosynthesis are inhibited by chronic exposure to high dose dexamethasone. It can be concluded that glucocorticoid might be involved in the multisteps of insulin release and biosynthesis.

Effect of seasonal changes on the transition between subclinical hypothyroid and euthyroid status

CONTEXT

The widespread use of thyroid tests in asymptomatic individuals identifies many patients with transient subclinical hypothyroidism.

OBJECTIVE

Our objective was to determine the effect of seasonal change on serum TSH levels and the transition between subclinical hypothyroid and euthyroid status.

DESIGN, SETTING, AND SUBJECTS

This was a retrospective longitudinal study of 1751 subclinical hypothyroid and 28 096 euthyroid subjects aged over 18 years who underwent serial thyroid function tests at a health screening center between October 2003 and May 2011.

MAIN OUTCOME MEASURES

Age-adjusted geometric mean values of the TSH level by month were calculated using linear mixed models. Adjusted odds ratios of test season and multiple baseline clinical factors were determined using generalized estimating equations.

RESULTS

During a median 36 months of follow-up, 57.9% of subclinical hypothyroid subjects reverted to euthyroidism, and 4.3% of euthyroid subjects developed subclinical hypothyroidism. The monthly distribution of follow-up TSH levels indicated a biphasic pattern, ie, an increase during the winter-spring season and a decrease during the summer-fall season, with a maximal TSH difference of 0.69 mIU/L in subclinical hypothyroid and 0.30 mIU/L in euthyroid subjects. Normalization of subclinical hypothyroidism was increased 1.4-fold in follow-up tests during the summer-fall follow-up, whereas subclinical hypothyroidism increased 1.4-fold in euthyroid subjects during the winter-spring follow-up.

CONCLUSIONS

The season in which thyroid testing was performed was independently related to the transition between subclinical hypothyroid and euthyroid status. Seasonal variations in TSH concentration should be considered before deciding on treatment of subclinical hypothyroidism, particularly in the areas with a wide annual temperature range.

Chitinase 3-like 1 drives allergic skin inflammation via Th2 immunity and M2 macrophage activation

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disorder characterized by defective skin barrier and Th2 immune responses. Chitinase 3-like 1 (CHI3L1), also known as breast regression protein 39 (BRP-39) in mice and human homologue YKL-40, plays important roles in Th2 inflammation and allergen sensitization. CHI3L1 has been implicated in a variety of diseases including asthma characterized by inflammation, apoptosis and tissue remodelling, but its role in AD remains elusive.

OBJECTIVE

The aim of this study was to investigate the role of CHI3L1 in the development and progression of AD.

RESULTS

We investigated YKL-40 levels in the serum and skin of AD patients by ELISA and immunofluorescence, respectively. Using a murine model of AD induced by ovalbumin (OVA), we investigated Th2 immune responses, M2 macrophage activation and skin barrier gene expression using wild-type (WT) and BRP-39 null mutant (BRP-39^-/- ) mice. YKL-40 level was significantly increased in serum of AD patients. In addition, both mRNA and protein expression levels of BRP-39 were higher in OVA-sensitized WT mice than in control mice. OVA-sensitized BRP-39^-/- mice showed decreased epidermal thickness, lower total serum IgE, Th2 cytokine levels and CD4⁺ effector T cell populations than OVA-sensitized WT mice. Induction of BRP-39 was dominant in dermal macrophages. BRP-39 deficiency was found to be involved in M2 macrophage activation. Consistently, the YKL-40 level in the skin of AD patients was higher than in normal subjects and it was expressed in dermal macrophages. BRP-39 deficiency attenuated dysregulation of skin barrier and tight junction genes.

CONCLUSIONS AND CLINICAL RELEVANCE

These findings demonstrate that CHI3L1 mediates the development of AD induced by OVA, affecting Th2 inflammation, M2 macrophage activation and skin barrier function.

Role of Ras/ERK-dependent pathway in the erythroid differentiation of K562 cells

The chronic myelogenous leukemic K562 cell line carrying Bcr-Abl tyrosine kinase is considered as pluripotent hematopoietic progenitor cells expressing markers for erythroid, granulocytic, monocytic, and megakaryocytic lineages. Here we investigated the signaling modulations required for induction of erythroid differentiation of K562 cells. When the K562 cells were treated with herbimycin A (an inhibitor of protein tyrosine kinase), ras antisense oligonucleotide, and PD98059 (a specific inhibitor of MEK), inhibition of ERK/MAPK activity and cell growth, and induction of erythroid differentiation were observed. The ras mutant, pZIPRas61leu-transfected cells, K562-Ras61leu, have shown a markedly decreased cell proliferation rate with approximately 2-fold doubling time, compared with the parental K562 cells, and about 60% of these cells have shown the phenotype of erythroid differentiation. In addition, herbimycin A inhibited the growth rate and increased the erythroid differentiation, but did not affect the elevated activity of ERK/MAPK in the K562-Ras61leu cells. On the other hand, effects of PD98059 on the growth and differentiation of K562-Ras61leu cells were biphasic. At low concentration of PD98059, which inhibited the elevated activity of ERK/MAPK to the level of parental cells, the growth rate increased and the erythroid differentiation decreased slightly, and at high concentration of PD98059, which inhibited the elevated activity of ERK/MAPK below that of the parental cells, the growth rate turned down and the erythroid differentiation was restored to the untreated control level. Taken together, these results suggest that an appropriate activity of ERK/MAPK is required to maintain the rapid growth and transformed phenotype of K562 cells.

Reliable and robust method for abdominal muscle mass quantification using CT/MRI: An explorative study in healthy subjects

Background

Quantification of abdominal muscle mass by cross-sectional imaging has been increasingly used to diagnose sarcopenia; however, the technical method for quantification has not been standardized yet. We aimed to determine an optimal method to measure the abdominal muscle area.

Methods

Among 50 consecutive subjects who underwent abdominal CT and MRI for possible liver donation, total abdominal muscle area (TAMA) and total psoas muscle area (TPA) at the L3 inferior endplate level were measured by two blinded readers. Inter-scan agreement between CT and MRI and inter-reader agreement between the two readers were evaluated using intraclass correlation coefficient (ICC) and within-subject coefficient of variation (WSCV). To evaluate the effect of measurement level, one reader measured TAMA and TPA at six levels from the L2 to L4 vertebral bodies.

Results

TAMA was a more reliable biomarker than TPA in terms of inter-scan agreement (ICC: 0.928 vs. 0.788 for reader 1 and 0.853 vs. 0.821 for reader 2, respectively; WSCV: 8.3% vs. 23.4% for reader 1 and 10.4% vs. 22.3% for reader 2, respectively) and inter-reader agreement (ICC: 0.986 vs. 0.886 for CT and 0.865 vs. 0.669 for MRI, respectively; WSCV: 8.2% vs. 16.0% for CT and 11.6% vs. 29.7% for MRI, respectively). In terms of the measurement level, TAMA did not differ from the L2_inf to L4_inf levels, whereas TPA increased with a decrease in measurement level.

Conclusions

TAMA is a better biomarker than TPA in terms of inter-scan and inter-reader agreement and robustness to the measurement level. CT was a more reliable imaging modality than MRI. Our results support the use of TAMA measured by CT as a standard biomarker for abdominal muscle area measurement.

Efficacy and Safety of Microwave Ablation for Malignant Renal Tumors: An Updated Systematic Review and Meta-Analysis of the Literature Since 2012

Objective

To systematically determine the treatment outcomes of percutaneous microwave ablation (MWA) in patients with malignant renal tumor.

Materials and Methods

Original studies that reported the clinical outcomes of MWA in patients with malignant renal tumors were identified in MEDLINE and EMBASE from 2012 to June 30, 2017. Inverse variance and random-effects models were used to evaluate and acquire meta-analytic summary estimates of various clinical outcomes, including technical outcomes (technical success rate [TSR] and technical efficacy rate [TER]), oncologic outcomes (local tumor recurrence rate [LRR], cancer-specific survival rate [CSSR], and overall survival rate [OSR]), and complications.

Results

Among the 145 articles screened, 13 articles including 567 patients carrying 616 malignant renal tumors were included in the meta-analysis. The meta-analytic pooled TSR and TER were 97.3% (95% confidence interval, 94.3-99.4%; I² = 0.0%) and 97.6% (95.0-99.4%, I² = 48.5%), respectively. The meta-analytic pooled LRR was 2.1% (0.3-4.7%, I² = 54.1%). At 1-, 2-, 3-, and 5-year follow-up time points, the meta-analytic pooled CSSRs were 99.1% (97.2-100.0%; I² = 0.0%), 98.4% (95.1-100.0%; I² = 31.2%), 97.6% (93.4-99.9%; I² = 52.3%), and 96.9% (93.3-99.2%; I² = 0.0%) respectively, while the OSRs were 98.3% (96.1-99.8%; I² = 0.0%), 94.9% (91.7-97.5%; I² = 0.0%), 86.8% (81.9-91.1%; I² = 22.1%), and 81.9% (75.4-87.6%; I² = 0.0%). In terms of major complications, a 1.8% (0.6-3.3%; I² = 0.0%) rate of meta-analytic pooled incidence was found.

Conclusion

Microwave ablation showed favorable technical and oncologic outcomes with a low incidence of major complications. Hence, image-guided percutaneous MWA can be considered as a safe and effective treatment for malignant renal tumors.

Peritoneal lymphomatosis: CT and PET/CT findings and how to differentiate between carcinomatosis and sarcomatosis

Peritoneal lymphomatosis is a rare manifestation of lymphoma, seen most frequently with non-Hodgkin lymphoma, and it is important to be familiar with this condition, because early diagnosis directly affects the management of patients. This review illustrates the spectrum of imaging findings in peritoneal lymphomatosis, highlighting the use of positron emission tomography/computed tomography, showing common and uncommon subtypes of lymphoma associated with this entity, and how to differentiate it from peritoneal carcinomatosis and peritoneal sarcomatosis.

Influence of human allogenic bone marrow and cord blood-derived mesenchymal stem cell secreting trophic factors on ATP (adenosine-5'-triphosphate)/ADP (adenosine-5'-diphosphate) ratio and insulin secretory function of isolated human islets from cadaveric donor

Successful islet transplantation (ITx) is not only dependent on the number of islets, but also their quality, including viability, metabolic activity, and function. Islet quality decreases during cultivation after the isolation procedure. To overcome this obstacle, we established the practice of islet and mesenchymal stem cells (MSCs) coculture. This coculture condition improved the ATP (adenosine-5'-triphosphate)/ADP (adenosine-5'-diphosphate) ratio and insulin secretory function in vitro. It is believed that the enhancement of islet quality in islet-MSCs cocultures may be caused by the secretion of active agents by MSCs. Herein we have shown that interleukin-6 (IL-6), vascular endothelial growth factor-A (VEGF-A), hepatocyte growth factor (HGF), and transforming growth factor-beta (TGF-beta) were significantly increased as measured by enzyme-linked immunosorbent assay (ELISA) in MSCs-cultured medium, factors that have been shown to improve the survival, function, and angiogenesis/revascularization of islets. These results indicated that the quality of human islets was enhanced by trophic molecules secreted by MSCs, which influence the intracellular islet ATP content and insulin secretory function.

Value of the dynamic and delayed MR sequence with Gd-DTPA in the T-staging of stomach cancer: correlation with the histopathology

BACKGROUND

To evaluate the usefulness of dynamic and delayed magnetic resonance (MR) imaging in the T-staging of stomach cancer and to compare the enhancement pattern of the cancerous lesion and the normal wall.

METHODS

We performed MR imaging in 46 patients with stomach cancer (including four early gastric cancers and 42 advanced gastric cancers). Axial, sagittal, or coronal two-dimensional fast low-angle shot) MR images for the water-distended stomach were obtained with dynamic protocol, including precontrast images and images obtained 30, 60, 90, and 240-300 s after intravenous injection of the 0.1 mM Gd-DTPA/kg solution. We evaluated the thickness, interruption (or not) of the low signal intensity bands, and enhancement pattern of the cancerous wall and normal gastric wall. We prospectively evaluated the depth of cancer invasion, perigastric infiltration (extraserosal invasion), perigastric organ invasion, and regional lymph nodes and determined tumor staging on MR images. These MR evaluations including MR-determined staging were correlated with the surgicopathologic findings.

RESULTS

Stomach cancer was shown as having a thickened wall with a rapid enhancing pattern after intravenous Gd-DTPA administration. The mucosa (and/or submucosa) affected by stomach cancer showed an early enhancement pattern (30-90 s after Gd-DTPA administration) in 43 of 46 patients (93%). The normal gastric mucosa demonstrated a delayed peak enhancement pattern (> 90 s after Gd-DTPA administration) in 29 of 46 patients (63%) and variable enhancement pattern in 17 of 46 patients (37%). An interrupted low signal intensity band or highly enhanced tumorous lesion penetrating through the gastric wall was seen in 17 of 19 pT3 patients (90%). Consistency between MR-determined staging and surgicopathologic staging occurred in three of four pT1 tumors (75%), 10 of 13 pT2 tumors (77%), 17 of 19 pT3 tumors (90%), and eight of 10 pT4 tumors (80%); overall accuracy was 83%. Overall accuracy of regional lymph node involvement, as determined by enhanced MR, was 52%; 24 of 46 node groups were positive.

CONCLUSIONS

Dynamic and delayed MR imaging can be useful for predicting depth of cancer invasion, perigastric infiltration (extraserosal invasion), and perigastric organ invasion by gastric cancer.

Sarcopenia as a Predictor of Future Cognitive Impairment in Older Adults

OBJECTIVES

We investigated the association between the indices of sarcopenia and future risk of cognitive impairment in older adults.

DESIGN

Community-based prospective cohort study.

SETTING

Community.

PARTICIPANTS

A total of 297 participants aged ≥65 years without cognitive impairment at baseline (mean age, 71.9 ± 6.6 years; men:women, 158:139) and who underwent cognitive evaluation at the 5-year follow-up.

MEASUREMENTS

Sarcopenia parameters including appendicular lean mass (ALM), handgrip strength, and the Short Physical Performance Battery (SPPB) score at baseline were compared according to the later progression of mild cognitive impairment (MCI) and/or dementia. The operational criteria suggested by the Foundation for the National Institutes of Health Sarcopenia Project were used. We performed multivariate logistic regression analysis to identify the independent indicators of the progression of cognitive impairment.

RESULTS

Among the 297 participants, 242 (81.5%) remained cognitively normal (nonprogression group), whereas 55 (18.5%) showed progression of cognitive impairment (50 subjects (16.8%) to MCI and 5 subjects (1.7%) to dementia) (progression group). Compared with the nonprogression group, subjects in the progression group were older, had a lower educational level, and had lower physical function as assessed by the SPPB; a higher percentage were depressed. Other baseline markers of sarcopenia, including the ALM-to-body mass index ratio and handgrip strength did not differ significantly between the groups. The association between a low SPPB score (<9) and progression of cognitive impairment was maintained after adjustment for conventional risk factors for cognitive impairment (hazard ratio 2.222, 95% confidence interval 1.047-4.716, P = 0.038).

CONCLUSION

Decreased physical performance, as assessed by the SPPB, but not other markers of sarcopenia, was independently associated with the risk of later cognitive impairment in older adults.

Involvement of the MAPK and PI3K pathways in chitinase 3-like 1-regulated hyperoxia-induced airway epithelial cell death

BACKGROUND

Exposure to 100% oxygen causes hyperoxic acute lung injury characterized by cell death and injury of alveolar epithelial cells. Recently, the role of chitinase 3-like 1 (CHI3L1), a member of the glycosyl hydrolase 18 family that lacks chitinase activity, in oxidative stress was demonstrated in murine models. High levels of serum CHI3L1 have been associated with various diseases of the lung, such as asthma, chronic obstructive pulmonary disease, and cancer. However, the role of CHI3L1 in human airway epithelial cells undergoing oxidative stress remains unknown. In addition, the signaling pathways associated with CHI3L1 in this process are poorly understood.

PURPOSE

In this study, we demonstrate the role of CHI3L1, along with the MAPK and PI3K signaling pathways, in hyperoxia-exposed airway epithelial cells.

METHOD

The human airway epithelial cell line, BEAS-2B, was exposed to >95% oxygen (hyperoxia) for up to 72h. Hyperoxia-induced cell death was determined by assessing cell viability, Annexin-V FITC staining, caspase-3 and -7 expression, and electron microscopy. CHI3L1 knockdown and overexpression studies were conducted in BEAS-2B cells to examine the role of CHI3L1 in hyperoxia-induced apoptosis. Activation of the MAPK and PI3K pathways was also investigated to determine the role of these signaling cascades in this process.

RESULTS

Hyperoxia exposure increased CHI3L1 expression and apoptosis in a time-dependent manner. CHI3L1 knockdown protected cells from hyperoxia-induced apoptosis. In contrast, CHI3L1 overexpression promoted cell death after hyperoxia exposure. Finally, phosphorylation of ERK1/2, p38, and Akt were affected by CHI3L1 knockdown.

CONCLUSION

This study indicates that CHI3L1 is involved in hyperoxia-induced cell death, suggesting that CHI3L1 may be one of several cell death regulators influencing the MAPK and PI3K pathways during oxidative stress in human airway epithelial cells.

Volumetric change of the graft bone after intertransverse fusion

STUDY DESIGN

Patients in whom good intertransverse fusion had been achieved were selected for the volumetric study of the fusion mass using sequential computed tomography scans.

OBJECTIVES

To assess the natural volumetric change of intertransverse fusion mass and the effect of the disease entity and spinal instrumentation on the fusion mass volume.

SUMMARY OF BACKGROUND DATA

The magnitude of volumetric change of the graft bone after intertransverse fusion is still inconclusive.

METHODS

Fifteen adult patients who underwent decompression surgery with single-level lumbar and lumbosacral intertransverse fusion were selected for this study. Preoperative diagnoses were degenerative spondylolisthesis in nine patients and isthmic spondylolisthesis in six. Seven of the 15 patients received pedicle screw fixation. They were categorized into two major groups: 1) instrumented and noninstrumented groups and 2) isthmic and degenerative groups. To assess the volumetric change of the graft bone, sequential computed tomography scans were obtained 2 weeks after surgery and again 18 months after surgery.

RESULTS

The overall initial mean graft volume was 6251 mm3, which decreased to 2842 mm3 by 18 months after surgery (P < 0.001). The overall mean volume loss between the two periods was 54.8% of the initial graft volume. Although there was no significant difference in the mean graft volume between the groups at either 2 weeks or 18 months after surgery (P > 0.05 in all comparisons), the mean graft volume in each group decreased significantly during the observation period (P < 0.01 in all comparisons). There was no significant difference in the mean volume loss or in the ratio of residual volume to the initial graft volume between the groups during the study period (P > 0.05 in all comparisons). The initial graft volume correlated positively with the graft volume at 18 months after surgery (r = 0.612, P < 0.01) and volume loss (r = 0.949, P < 0.01), but negatively with the residual volume ratio (r = -0.507, P < 0.01).

CONCLUSIONS

These results showed that more than one half of the initial graft bone volume was being absorbed during the consolidation processes of the graft bone, and that the volume loss during the period was not significantly affected by the spinal instrumentation or by the disease entity. It was also found that the greater the amount of the initial graft bone, the larger the fusion mass at 18 months after surgery. The volume loss, however, increased proportionally to an increase in the initial graft bone volume. The efficiency (ratio of residual volume to the initial graft volume) of the intertransverse fusion also tended to decline as the initial graft volume increased.

Association between apolipoprotein E polymorphism and Alzheimer's disease in Koreans

We analyzed the aplolipoprotein E (APOE) genotypes of 110 probable AD patients and 226 cognitively normal controls in Koreans. The APOE epsilon4 allele was more prevalent in both early- and late-onset AD patients (P < 0.01) than in controls. The odds for the APOE epsilon4-heterozygous subjects were 2.7 (95% CI = 1.6-4.5), and those for the APOE epsilon4-homozygous subjects were 17.4 (95% CI = 2.0-147.3). But the odds were not uniform across age groups, and were higher in women than in men. Although the APOE epsilon2 allele frequency did not differ by diagnosis, the patients carrying an APOE epsilon2 allele showed delayed age-at-onset (P = 0.02). In conclusion, the APOE e4 allele increased the risk for AD in dose-dependent manner, and the APOE epsilon4-conferred AD risk was age- and sex-dependent in Koreans.

Free-breathing dynamic contrast-enhanced MRI of the abdomen and chest using a radial gradient echo sequence with K-space weighted image contrast (KWIC)

OBJECTIVES

To evaluate the feasibility of free-breathing, dynamic contrast-enhanced (DCE) MRI of the abdomen and thorax using the radial-gradient-echo sequence with k-space weighted image contrast (KWIC) reconstruction.

METHODS

Institutional review board approval was obtained. Fourteen patients underwent free-breathing radial DCE-MRI. Radial MRI yielded full-frame images by gridding all k-space data and time-resolved subframe images by using KWIC reconstruction technique. Using subframe KWIC images, voxel-wise perfusion maps were created. For comparison, the breath-hold conventional Cartesian 3D-gradient-echo sequence (VIBE) was also performed during the equilibrium phase. The image qualities of radial and conventional VIBE images were compared quantitatively and qualitatively.

RESULTS

Radial DCE-MRI provided high spatial resolution (1.4 × 1.4 mm) and temporal resolution (4.1 s for subframe images) allowing voxel-wise perfusion mapping with negligible motion or streaking artefacts. There were no significant differences in SNR between full-frame radial images and conventional VIBE images (79.08 vs 74.80, P > 0.05). Overall image quality score of full-frame radial images was slightly lower than that of conventional VIBE images (3.88 ± 0.59 vs. 4.31 ± 0.97, P < 0.05), but provided clinically useful images.

CONCLUSIONS

The free-breathing radial DCE-MRI can provide high spatial and temporal resolution while maintaining reasonably high image quality and thus is a feasible technique for DCE-MRI in the abdomen and thorax.

KEY POINTS

• Dynamic contrast-enhanced magnetic resonance imaging (DCE) MRI is important in oncological imaging • Radial MRI with k-space weighted image contrast (KWIC) reconstruction offers potential improvements • Radial DCE-MRI provides good image quality, reduced artefacts and high spatial/temporal resolution.

Vitamin D levels in allergic rhinitis: a systematic review and meta-analysis

BACKGROUND

We aimed to systematically review observational studies investigating the relationship between vitamin D levels and allergic rhinitis (AR).

METHODS

Studies were selected if they evaluated the relationship between vitamin D levels and AR, and included studies that evaluated other allergic conditions if those studies also contained data on AR. We assessed the incidence and prevalence of AR according to vitamin D levels and compared vitamin D levels in patients with AR to levels in controls.

RESULTS

Nineteen studies were selected. Of these, only seven focused solely on AR; 10 studies evaluated the other allergic diseases as well as AR; and two studies evaluated asthma primarily, but also included data on patients with AR. The pooled odds ratios (ORs) for the incidence of AR according to vitamin D levels were not statistically significant for either children or adults. Lower vitamin D levels were associated with a higher AR prevalence only in children (pooled OR [95% confidence interval (CI)], 0.75 [0.58, 0.98]). The pooled mean vitamin D level in patients with AR was lower than that of controls only in children (pooled means difference [95% CI], -7.63 [-13.08, -2.18]).

CONCLUSIONS

Prior vitamin D levels were not related to developing AR, but lower vitamin D levels were associated with a higher AR prevalence only in children. There is insufficient evidence to support vitamin D supplementation for AR prevention. However, physicians should consider evaluating patients for vitamin D deficiency during AR management, especially in children.

Characterization of the T cell antigen receptor--p60fyn protein tyrosine kinase association by chemical cross-linking

Engagement of the TCR by specific antigen results in activation of a tyrosine kinase pathway. A candidate for the kinase responsible for the rapid tyrosine phosphorylation detected with T cell activation is p60fyn, a member of the src kinase family. In an earlier study [Samelson et al. (1990) Proc. Natl Acad. Sci. USA 87:4358] this enzyme was co-immunoprecipitated with the TCR from T cells solubilized in digitonin. In that study a sensitive in vitro kinase assay was used to detect the associated p60fyn. It was subsequently found that the reproducibility of the interaction depended on lot-to-lot variations in digitonin. To eliminate the possibility that the association of antigen receptor and kinase is an artifact of solubilization with ill-defined digitonin preparations, a cross-linking protocol was developed to stabilize the interaction between the TCR and p60fyn. T cells were permeabilized with tetanolysin and proteins were cross-linked with the water soluble chemical cross-linker, 3,3' dithiobis(sulfosuccinimidylpropionate). These experiments allowed the confirmation of the interaction between the TCR, p60fyn, and several additional proteins. The cross-linking studies also enabled the mapping of the interaction of p60fyn and associated proteins to the TCR zeta-chain. This technique should have a general use in stabilizing interactions between other receptors and molecules required for intracellular signaling.

Comparison of allergic indices in monosensitized and polysensitized patients with childhood asthma

Monosensitization differs both immunologically and clinically from polysensitization, and specific immunotherapy is more effective in patients sensitized only to a single pollen than in multiple-pollen sensitized patients. To further examine the differences between monosensitized and polysensitized allergies, allergic indices were examined in 68 monosensitized and 62 polysensitized patients with childhood asthma. Measurements included symptom scores, eosinophil counts, skin prick tests, serum total and specific IgE levels, and IL-10 levels, and were used to compare allergic indices between the two groups. Patients were followed for 18 months following immunotherapy to examine the effectiveness of the treatment. Symptom scores and total IgE levels were significantly higher in the polysensitized group than those in the monosensitized group (p<0.05). The levels of skin test response decreased significantly in both groups following immunotherapy. In the monosensitized group, symptom scores and specific IgE levels were significantly reduced after immunotherapy (p<0.05). In the polysensitized group, symptom scores were reduced after immunotherapy (p<0.05), but the degree of reduction was less than that of the monosensitized group (p<0.05). Moreover, in the polysensitized group, specific IgE levels after immunotherapy did not differ from that before immunotherapy. Serum IL-10 levels were not significantly increased after immunotherapy in either group. In conclusion, polysensitized patients tend to show higher allergic indices and immunotherapy might be less effective for these patients.

Insulin-like growth factor II (IGF-II) secreted from HepG2 human hepatocellular carcinoma cells shows angiogenic activity

Hepatocellular carcinoma (HCC) is a typical hypervascular tumor. Since insulin-like growth factor II (IGF-II) has been reported to play a significant role in liver regeneration and hepatocarcinogenesis, we initially examined its angiogenic effect on the chorioallantoic membrane (CAM) of 9-day-old chick embryos. We also investigated whether IGF-II secreted from HepG2 human hepatocellular carcinoma cells induces vascularization using the chick embryo CAM. We found that the concentrated conditioned media (CCM) of HepG2 cell culture induced angiogenesis on the CAM. We also identified IGF-II protein in the CCM from HepG2 cells by Western blot analysis. However, CCM from Chang liver cells, which are normal human liver cells and were free of IGF-II, did not induce angiogenesis in the CAM. These results suggest that IGF-II secreted from hepatocellular carcinoma cells may act as an angiogenic factor for the hypervascularization of HCC.

Nodular hepatocellular carcinoma. Treatment with subsegmental intraarterial injection of iodine 131-labeled iodized oil

Internal radiation therapy with subsegmental arterial injection of iodine 131(131I)-labeled iodized oil (Lipiodol; Laboratorie, Guerbet, France) was evaluated in 24 patients with nodular hepatocellular carcinoma (HCC) ranging from 2.5 to 8.0 cm in size. 131I Lipiodol (555 to 2220 MBq in 3 to 8 ml) was injected depending on the tumor size. Tumor reduction was seen in 88.9% of tumors smaller than 4.0 cm in diameter, 65.5% of tumors between 4.1 to 6.0 cm, and 25.0% of tumors larger than 5.1 cm. The tumor size reduction corresponded to the gradual drop of serum alpha-fetoprotein (AFP) levels and devascularization on follow-up angiography. Adverse reactions from treatment included fever, mild abdominal pain, nausea, and elevation of transaminases. These were mild and well tolerated by patients. This method provided long-term local control without complications related to the thyroid, lung, gastrointestinal tract, and bone marrow.