Computer-Assisted Detection of Cerebral Aneurysms in MR Angiography in a Routine Image-Reading Environment: Effects on Diagnosis by Radiologists

BACKGROUND AND PURPOSE

Experiences with computer-assisted detection of cerebral aneurysms in diagnosis by radiologists in real-life clinical environments have not been reported. The purpose of this study was to evaluate the usefulness of computer-assisted detection in a routine reading environment.

MATERIALS AND METHODS

During 39 months in a routine clinical practice environment, 2701 MR angiograms were each read by 2 radiologists by using a computer-assisted detection system. Initial interpretation was independently made without using the detection system, followed by a possible alteration of diagnosis after referring to the lesion candidate output from the system. We used the final consensus of the 2 radiologists as the reference standard. The sensitivity and specificity of radiologists before and after seeing the lesion candidates were evaluated by aneurysm- and patient-based analyses.

RESULTS

The use of the computer-assisted detection system increased the number of detected aneurysms by 9.3% (from 258 to 282). Aneurysm-based analysis revealed that the apparent sensitivity of the radiologists' diagnoses made without and with the detection system was 64% and 69%, respectively. The detection system presented 82% of the aneurysms. The detection system more frequently benefited radiologists than being detrimental.

CONCLUSIONS

Routine integration of computer-assisted detection with MR angiography for cerebral aneurysms is feasible, and radiologists can detect a number of additional cerebral aneurysms by using the detection system without a substantial decrease in their specificity. The low confidence of radiologists in the system may limit its usefulness.

Salivary pathogen and serum antibody to assess the progression of chronic periodontitis: a 24-mo prospective multicenter cohort study

BACKGROUND AND OBJECTIVE

A diagnosis of periodontitis progression is presently limited to clinical parameters such as attachment loss and radiographic imaging. The aim of this multicenter study was to monitor disease progression in patients with chronic periodontitis during a 24-mo follow-up program and to evaluate the amount of bacteria in saliva and corresponding IgG titers in serum for determining the diagnostic usefulness of each in indicating disease progression and stability.

MATERIAL AND METHODS

A total of 163 patients with chronic periodontitis who received trimonthly follow-up care were observed for 24 mo. The clinical parameters and salivary content of Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans were assessed using the modified Invader PLUS assay, and the corresponding serum IgG titers were measured using ELISA. The changes through 24 mo were analyzed using cut-off values calculated for each factor. One-way ANOVA or Fisher's exact test was used to perform between-group comparison for the data collected. Diagnostic values were calculated using Fisher's exact test.

RESULTS

Of the 124 individuals who completed the 24-mo monitoring phase, 62 exhibited periodontitis progression, whereas 62 demonstrated stable disease. Seven patients withdrew because of acute periodontal abscess. The ratio of P. gingivalis to total bacteria and the combination of P. gingivalis counts and IgG titers against P. gingivalis were significantly related to the progression of periodontitis. The combination of P. gingivalis ratio and P. gingivalis IgG titers was significantly associated with the progression of periodontitis (p = 0.001, sensitivity = 0.339, specificity = 0.790).

CONCLUSIONS

It is suggested that the combination of P. gingivalis ratio in saliva and serum IgG titers against P. gingivalis may be associated with the progression of periodontitis.

Periostin of human periodontal ligament fibroblasts promotes migration of human mesenchymal stem cell through the αvβ3 integrin/FAK/PI3K/Akt pathway

BACKGROUND AND OBJECTIVE

The periodontal ligament (PDL) is characterized by rapid turnover, high remodeling capacity and high inherent regenerative potential compared with other connective tissues. Periostin, which is highly expressed in the fibroblasts in the PDL, has been widely discussed in relation to collagen fibrillogenesis in the PDL. Recently, several reports have indicated periostin in cell migration. The aim of this study was to examine whether human PDL fibroblasts (hPDLFs) with high levels of periostin expression promote the migration of human bone marrow mesenchymal stem cells (hMSCs).

MATERIAL AND METHODS

The migration of hMSCs was examined by transwell chamber migration assay under different conditions: medium alone, hPDLFs, human dermal fibroblasts, recombinant periostin, integrin αvβ3 blocking antibody (anti-CD51/61 antibody) and inhibitors of FAK (PF431396) and PI3K (LY294002). Phosphorylation of FAK and Akt in hMSCs under stimulation of periostin was examined by western blotting.

RESULTS

The migration assay revealed that the number of migrated hMSCs by hPDLFs was significantly larger than those by dermal fibroblasts, periostin small interfering RNA hPDLFs and medium alone. Furthermore, recombinant periostin also strongly induced hMSC migration. The addition of anti-CD51/61 antibody, PF431396 and LY294002 caused a significant reduction in the number of migrated hMSCs respectively. The anti-CD51/61 antibody inhibited both FAK and Akt phosphorylations under periostin stimulation. PF431396 inhibited both FAK and Akt phosphorylations. LY294002 inhibited only Akt phosphorylation, and FAK phosphorylation was not influenced under periostin stimulation.

CONCLUSION

Periostin expression in hPDLFs promotes the migration of hMSCs through the αvβ3 integrin/FAK/PI3K/Akt pathway in vitro.

Circulating platelet-neutrophil aggregates play a significant role in Kawasaki disease

BACKGROUND

Circulating platelet-neutrophil aggregates play a crucial role in amplifying acute inflammation and could promote adverse effects involving vascular injury. The aim of this study was to evaluate the role of platelet-neutrophil aggregates in Kawasaki disease (KD).

METHODS AND RESULTS

Forty patients with KD (30 intravenous immunoglobulin [IVIG] responders and 10 IVIG non-responders), 7 febrile patients with bacterial infections, and 9 normal volunteers were analyzed. Thirty-three patients with KD were treated with IVIG, and 7 were treated with IVIG plus prednisolone. We evaluated the rate of platelet-neutrophil aggregates and measured the platelet factor 4 (PF4) and β-thromboglobulin (β-TG) levels. The rate of platelet-neutrophil aggregates was significantly higher in patients with KD than those with bacterial infection and normal volunteers. The rate of platelet-neutrophil aggregates was significantly higher in patients with coronary artery abnormalities (CAA) than in those without CAA, and was correlated with PF4 and β-TG levels in patients with KD. Comparing time-course analysis, the rate of platelet-neutrophil aggregates was significantly decreased in patients treated with IVIG plus prednisolone than in those treated with IVIG alone.

CONCLUSIONS

The findings demonstrate that platelet-neutrophil aggregates are significantly present in higher rates and are closely related to pathological developments of CAA in KD. Additional prednisolone treatment for patients in the acute phase of KD could suppress platelet-neutrophil aggregates, indicating that platelet-neutrophil aggregates would inhibit amplified reciprocal vascular inflammatory activation.

Fate of graft cells: what should be clarified for development of mesenchymal stem cell therapy for ischemic stroke?

Mesenchymal stem cells (MSCs) are believed to be promising for cell administration therapy after ischemic stroke. Because of their advantageous characteristics, such as ability of differentiation into neurovascular lineages, avoidance of immunological problems, and abundance of graft cells in mesodermal tissues, studies regarding MSC therapy have increased recently. However, several controversies are yet to be resolved before a worldwide consensus regarding a standard protocol is obtained. In particular, the neuroprotective effects, the rate of cell migration to the lesion, and differentiation direction differ depending on preclinical observations. Analyses of these differences and application of recent developments in stem cell biology or engineering in imaging modality may contribute to identification of criteria for optimal stem cell therapy in which reliable protocols, which control cell quality and include safe administration procedures, are defined for each recovery phase after cerebral ischemia. In this mini review, we examine controversies regarding the fate of grafts and the prospects for advanced therapy that could be obtained through recent developments in stem cell research as direct conversion to neural cells.

Immunoglobulin G values before treatment are correlated with the responsiveness to initial intravenous immunoglobulin therapy for Kawasaki disease

BACKGROUND

Low levels of serum immunoglobulin G (IgG) before intravenous immunoglobulin (IVIG) therapy for Kawasaki disease (KD) have been reported as one of the risk factors for coronary artery abnormalities (CAAs). This risk factor needs to be re-evaluated because the dosage of IVIG has changed from 0.2-0.4 g/kg/day for 5 days to a single high dose of 2 g/kg.

METHODS

We reviewed the clinical records of KD patients admitted to our hospital from January 2001 to August 2011. Patients who were given a single high dose of IVIG within 7 days of illness, and who had blood collected for serum immunoglobulin values before treatment, were selected. The serum immunoglobulin levels and coronary artery diameters measured by echocardiogram were transformed to z-scores.

RESULTS

The subjects were 197 KD patients, including 22 IVIG nonresponders and 16 patients with CAAs. Of these, 150 (76%) had a z-score for IgG (IgGz) of ≤0. There were no differences in IgGz values between patients with CAAs and those without CAAs. However, nonresponders had higher IgGz values than responders (median, 25th percentile and 75th percentile: -0.26, -0.83 and 0.34 vs. -0.79, -1.40 and -0.03; p = 0.020). Logistic regression analysis showed that the IgGz value was an independent risk factor for resistance to IVIG (OR 1.36, 95% CI 1.002-1.849; p = 0.048).

CONCLUSIONS

Low IgGz values were not a risk factor for CAAs in this study. However, KD patients with relatively high IgGz values before treatment may have an increased risk of resistance to initial IVIG therapy. © 2014 S. Karger AG, Basel.

Sequence variations at I260 and A1731 contribute to persistent currents in Drosophila sodium channels

Tetrodotoxin-sensitive persistent sodium currents, INaP, that activate at subthreshold voltages, have been detected in numerous vertebrate and invertebrate neurons. These currents are believed to be critical for regulating neuronal excitability. However, the molecular mechanism underlying INaP is controversial. In this study, we identified an INaP with a broad range of voltage dependence, from -60mV to 20mV, in a Drosophila sodium channel variant expressed in Xenopus oocytes. Mutational analysis revealed that two variant-specific amino acid changes, I260T in the S4-S5 linker of domain I (ILS4-S5) and A1731V in the voltage sensor S4 of domain IV (IVS4), contribute to the INaP. I260T is critical for the portion of INaP at hyperpolarized potentials. The T260-mediated INaP is likely the result of window currents flowing in the voltage range where the activation and inactivation curves overlap. A1731V is responsible for impaired inactivation and contributes to the portion of INaP at depolarized potentials. Furthermore, A1731V causes enhanced activity of two site-3 toxins which induce persistent currents by inhibiting the outward movement of IVS4, suggesting that A1731V inhibits the outward movement of IVS4. These results provided molecular evidence for the involvement of distinct mechanisms in the generation of INaP: T260 contributes to INaP via enhancement of the window current, whereas V1731 impairs fast inactivation probably by inhibiting the outward movement of IVS4.

Evaluation of hamstring muscle strength and morphology after anterior cruciate ligament reconstruction

This study aimed to clarify the relationship between knee flexor strength and hamstring muscle morphology after anterior cruciate ligament (ACL) reconstruction using the semitendinosus (ST) tendon and to determine the causative factors of decreased knee flexor muscle strength. Fourteen male and ten female patients who resumed sports activities after surgery participated in the experiment. Isometric knee flexion torque was measured at 30°, 45°, 60°, 90°, and 105° of knee flexion. Magnetic resonance imaging (MRI) was used to calculate ST muscle length and hamstring muscle volume, and to confirm the status of ST tendon regeneration. The correlation between the MRI findings and flexor strength was analyzed. Regenerated ST tendon was confirmed in 21 of the 24 patients, but muscle volume (87.6%) and muscle length (74.5%) of the ST in the operated limb were significantly smaller than those in the normal limb. The percentage of the knee flexion torque of the operated limb compared with that of the normal was apparently lower at 105° (69.1%) and 90° (68.6%) than at 60° (84.4%). Tendon regeneration, ST muscle shortening, and ST muscle atrophy correlated with decreased knee flexion torque. These results indicated that preserving the morphology of the ST muscle-tendon complex is important.

Loss-of-function mutations in the gene encoding filaggrin underlie a Japanese family with food-dependent exercise-induced anaphylaxis

BACKGROUND

Food-dependent exercise-induced anaphylaxis (FDEIA) is a serious food allergy in which anaphylaxis develops when exercise is performed within several hours after food intake. The precise mechanism underlying allergic sensitization in FDEIA has been an important issue but remains poorly understood.

OBJECTIVES

We aimed to elucidate the pathomechanism including the route of allergen sensitization involved in FDEIA.

METHODS

A Japanese family with wheat-dependent exercise-induced anaphylaxis (WDEIA), a specific form of FDEIA, were clinically examined. Mutation analysis of the gene encoding filaggrin (FLG) was also performed.

RESULTS

Two of the family members were confirmed as WDEIA on the basis of their medical history and positive provocation test results. Notably, the two affected individuals in the family had concomitant ichthyosis vulgaris. Mutation analysis of FLG revealed that they carry one or more loss-of-function mutations that have not been described in the Japanese population.

CONCLUSION

These results indicate that FLG mutations might be involved in the pathogenesis of WDEIA in the present case.

Adipose cells induce phospho-Thr-172 AMPK production by epinephrine or CL316243 in mouse 3T3-L1 adipocytes or MAPK activation and G protein-associated PI3K responses induced by CL316243 or aluminum fluoride in rat white adipocytes

Responses of adipose cells to adrenoceptor regulation, including that of β-adrenoceptor (AR), and the signalling machinery involved in these responses are not sufficiently understood; information that is helpful for elucidating the adrenoceptor (adrenergic and β-AR)-responsive machinery is insufficient. We examined phospho-Thr-172 AMPK production in mouse-derived 3T3-L1 adipocytes treated with epinephrine or CL316243 (a β3-AR agonist) for 15 min. We also examined MAPK activation or G protein-associated PI3K activation or -associated PI3K p85 complex formation in rat epididymal (white) adipocytes treated with CL316243 for 15 min or aluminum fluoride (a G-protein signalling activator) for 20 min. Furthermore, we examined the effect of PTX (a trimeric G-protein inactivator) on p85 complex formation induced by aluminum fluoride treatment. Western blot analysis revealed that epinephrine or CL316243 treatment increased the phospho- Thr-172 AMPK (an active form of AMPK) level in 3T3-L1 adipocytes. Activated kinase analysis with a specific substrate showed that CL316243 or aluminum fluoride treatment activated MAPK in rat adipocytes. Immunoprecipitation experiments with a G-protein β subunit (Gβ) antibody showed that treatment of rat adipocytes with CL316243 activated PI3K and increased the PI3K p85 level in the Gβ antibody immunoprecipitates. Such an increase in the p85 level was similarly elicited by aluminum fluoride treatment in a PTX-sensitive manner. Our results provide possible clues for clarifying the signalling machinery involved in adrenoceptor responses, including those of β3-AR, in mouse-derived adipocytes and rat white adipocytes. Our findings advance the understanding of responses to adrenoceptor regulation in adipose cells and of the cellular signalling machinery present in the cells.

Oral administration of bovine lactoferrin attenuates ultraviolet B-induced skin photodamage in hairless mice

Lactoferrin (LF) is recognized as a host defensive glycoprotein, especially for newborn infants. The aim of this study was to investigate whether orally administered LF had protective activity against UV-induced skin damage in hairless mice. Transepidermal water loss and skin hydration were evaluated in nonirradiated mice, UVB-irradiated mice, and UVB-irradiated and LF-administered mice. Supplementation with LF (1,600 mg/kg per day) effectively suppressed the increase in transepidermal water loss, reduction in skin hydration, aberrant epidermal hyperplasia, and cell apoptosis induced by UV irradiation. Although no significant changes in superoxide dismutase-like activity or malondialdehyde levels were observed in the skin with both UV irradiation and LF administration, UV-stimulated IL-1β levels in the skin were significantly suppressed by the administration of LF. Oral supplementation with LF has the potential to reduce IL-1β levels and prevent UV-induced skin damage. Further studies are needed to elucidate the relationships between the antiinflammatory effects and skin protective function of LF.

Comparison of (11)C-methionine, (11)C-choline, and (18)F-fluorodeoxyglucose-PET for distinguishing glioma recurrence from radiation necrosis

The aim of this study is to assess the different metabolic activities characteristic of glioma recurrence and radiation necrosis (RN) and to explore the diagnostic accuracy for differentiation of the two conditions using ¹¹C-methionine (MET), ¹¹C-choline (CHO), and ¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography (PET). Fifty patients with lesions suggestive of recurrent glioma by magnetic resonance imaging (MRI) underwent MET, CHO, and FDG-PET. All patients who had previously been treated with radiotherapy for malignant glioma were subjected to open surgery and pathological diagnosis (17 recurrent grade 3- gliomas (Gr.3s) comprising 7 anaplastic astrocytomas (AAs) and 10 anaplastic oligodendrogliomas (AOs), 17 recurrent glioblastomas (Gr.4s), and 16 RNs). We measured the PET/Gd volume ratio, the PET/Gd overlap ratio, and the lesion/normal brain uptake ratio (L/N ratio) and determined the optimal index of each PET scan. The PET/Gd volume ratio and the PET/Gd overlap ratio for RN were significantly lower than those of glioma recurrence only with MET-PET (P < 0.05). The L/N ratio of RN was significantly lower than that of Gr.4 with all PET imaging (P < 0.001) and was significantly lower than that of Gr.3, especially for AO, only with MET-PET images (P < 0.005). Receiver operating characteristic (ROC) analysis showed that the area under the curve of MET, CHO, and FDG was 92.5, 81.4, and 77.4, respectively. MET L/N ratio of greater than 2.51 provided the best sensitivity and specificity for establishing glioma recurrence (91.2% and 87.5%, respectively). These results demonstrated that MET-PET was superior to both CHO and FDG-PET for diagnostic accuracy in distinguishing glioma recurrence from RN.

The conversion of lysine into piperidine, cadaverine, and pipecolic acid in the brain and other organs of the mouse

The biosynthesis of piperidine, a possible neuromodulator, and its presumed precursors cadaverine and pipecolic acid, has been investigated in the mouse under in vitro conditions. Conversion of lysine into piperidine was observed only in the intestines and is probably caused by the intestinal flora. Formation of cadaverine and pipecolic acid from lysine was observed in the brain, liver, kidney, and large intestine. In addition, pipecolic acid was formed in the heart. The possible contributions of the diet and of the intestinal bacteria to the endogenous pool(s) of piperidine are discussed.

Electrocardiographic Screening of 1-Month-Old Infants for Identifying Prolonged QT Intervals

Background—

Neonatal electrocardiographic screening is used to screen infants with prolonged QT intervals, as previously shown in whites. However, this procedure needs to be confirmed in other ethnic groups.

Methods and Results—

In 8 areas in Japan, an ECG was recorded in 4285 infants at 1-month medical checkup. A prospective study showed that a provisional criterion of QTc ≥470 ms was appropriate for infants. To assess the validity of the criterion, all infants with a QTc between 460 and 470 ms were followed up. Five infants had a QTc ≥470 ms. Four infants were diagnosed with prolonged QT intervals from follow-up ECGs. Four infants showed no symptoms and did not have a family history of long-QT syndrome. Two infants showed progressive prolongation of QT intervals, and medication was started. Genetic testing was performed in 3 of 4 infants with prolonged QT intervals, and it revealed a KCNH2 mutation (3065 delT, L1021fs+34X) in 1 infant. One infant with a QTc ≥470 ms and 2 infants with a QTc between 460 and 470 ms showed a decline in their QTc values during follow-up. The study screened another infant with Wolff–Parkinson–White syndrome who was diagnosed with noncompaction before symptoms appeared.

Conclusions—

Neonatal electrocardiographic screening can identify infants likely to be affected by long-QT syndrome in the Japanese population, as already shown in whites. This screening may also be useful in identifying other important cardiac diseases.