Myelin and Axonal Damage in Normal-Appearing White Matter in Patients with Moyamoya Disease

BACKGROUND AND PURPOSE

Although chronic ischemia is known to induce myelin and axonal damage in animal models, knowledge regarding patients with Moyamoya disease is limited. We aimed to investigate the presence of myelin and axonal damage in Moyamoya disease and their relationship with cognitive performance.

MATERIALS AND METHODS

Eighteen patients with Moyamoya disease (16-55 years of age) and 18 age- and sex-matched healthy controls were evaluated with myelin-sensitive MR imaging based on magnetization transfer saturation imaging and 2-shell diffusion MR imaging. The myelin volume fraction, which reflects the amount of myelin sheath; the g-ratio, which represents the ratio of the inner (axon) to the outer (axon plus myelin) diameter of the fiber; and the axon volume fraction, which reflects axonal components, were calculated and compared between the patients and controls. In the patients with Moyamoya disease, the relationship between these parameters and cognitive task-measuring performance speed was also evaluated.

RESULTS

Compared with the healthy controls, the patients with Moyamoya disease showed a significant decrease in the myelin and axon volume fractions (P < .05) in many WM regions, while the increases in the g-ratio values were not statistically significant. Correlations with cognitive performance were most frequently observed with the axon volume fraction (r = 0.52-0.54; P < .03 in the right middle and posterior cerebral artery areas) and were the strongest with the g-ratio values in the right posterior cerebral artery region (r = 0.64; P = .004).

CONCLUSIONS

Myelin-sensitive MR imaging and diffusion MR imaging revealed that myelin and axonal damage exist in patients with Moyamoya disease. The relationship with cognitive performance might be stronger with axonal damage than with myelin damage.

AB0154 MERTK AND THE RESOLUTION OF INFLAMMATION IN IGG4-RELATED DISEASE

Background:

IgG4-Related Disease (IgG4-RD) is characterized by fibrotic lesions, serum IgG4 elevation, and prompt response to glucocorticoids. B and T lymphocytes are considered the initiators of tissue inflammation in IgG4-RD, but the prominent stromal reaction observed at disease sites suggest that a dysregulation of processes involved in the resolution of inflammation could be pathologically relevant as well. Mer receptor tyrosine kinase (MerTK) and its ligands protein S (Pros1) have a pivotal role in the resolution of inflammation through the activation of a well-characterized signaling pathway that ultimately dampens the immune response and promotes the recovery of tissue function. MerTK and the processes involved in the resolution of inflammation have never been addressed in IgG4-RD.

Objectives:

To investigate MerTK involvement in the pathogenesis of IgG4-RD by evaluating (a) the expression of MerTK and of its endogenous ligands in IgG4-RD tissues; (b) the presence of circulating precursors of MerTK+ cells infiltrating IgG4-RD lesions in the peripheral blood of IgG4-RD patients; (c) the effects of immunosuppressive therapies on MerTK expression in IgG4-RD tissues.

Methods:

Three distinct cohorts of IgG4-RD patients were included in this study. 8 active patients were used for immunohistochemistry studies for MerTK expression. 16 IgG4-RD and 14 Sjögren syndrome patients, together with 6 control tonsils, were used for multicolor immunofluorescence studies and TissueQuest software quantification of the expression of MerTK, CD68, CD163, Pros1, Gas6, CD4, SLAMF7, CD19, IgG4, cleaved caspase-3. 10 untreated IgG4-RD patients were used to evaluate MerTK expression in circulating monocytes subsets and fibrocytes by flow cytometry.

Results:

MerTK was highly expressed in IgG4-RD affected organs. MerTK+ cells accounted on average for 16% (range 5-35%) of all cells in the tissue, and the majority of them expressed CD68,reflecting a monocyte-macrophage origin. 33.5 % (interquartile range (IQR) 26-41%) of MerTK+ cells co-expressed CD68 and CD163, while 30.5% (IQR 19-41.5%) expressed CD68 but not CD163. CD68+MerTK+ cells displayed two main morphological appearances, compatible with those of macrophages and of myofibroblasts. In addition, MerTK+ cell number was significantly increased in salivary glands from IgG4-RD patients compared to Sjögren syndrome (p < 0.0001). Circulating precursors of CD68+MerTK+ cells infiltrating IgG4-RD lesions were identified by flow cytometery in the peripheral blood of patients with active IgG4-RD as MerTK+ populations of intermediate monocytes, nonclassical monocytes and collagen expressing fibrocytes. MerTK ligand Pros1 was exposed on 52% (IQR 42-57%) of infiltrating B lymphocytes, 74% (IQR 54-89%) of infiltrating T lymphocytes, and, likely, on apoptotic cells that were detected in IgG4-RD tissues. CD68+MerTK+ cells were found in physical contact with Pros1+ cells in IgG4-RD lesions and their number decreased by 56% after successful treatment with rituximab.

Conclusion:

MerTK is abundant in IgG4-RD affected organs and is preferentially expressed on CD68+ macrophages and myofibroblasts that infiltrate IgG4-RD lesions. MerTK+ cells might interact with apoptotic cells and Pros1 expressing T and B lymphocytes in IgG4-RD tissues, leading to the persistent activation of processes involved in the resolution of inflammation and promoting the development of tissue fibrosis.

Disclosure of Interests:

None declared

Bayesian Estimation of CBF Measured by DSC-MRI in Patients with Moyamoya Disease: Comparison with 15O-Gas PET and Singular Value Decomposition

BACKGROUND AND PURPOSE

CBF analysis of DSC perfusion using the singular value decomposition algorithm is not accurate in patients with Moyamoya disease. This study compared the Bayesian estimation of CBF against the criterion standard PET and singular value decomposition methods in patients with Moyamoya disease.

MATERIALS AND METHODS

Nineteen patients with Moyamoya disease (10 women; 22-52 years of age) were evaluated with both DSC and ¹⁵O-gas PET within 60 days. DSC-CBF maps were created using Bayesian analysis and 3 singular value decomposition analyses (standard singular value decomposition, a block-circulant deconvolution method with a fixed noise cutoff, and a block-circulant deconvolution method that adopts an occillating noise cutoff for each voxel according to the strength of noise). Qualitative and quantitative analyses of the Bayesian-CBF and singular value decomposition-CBF methods were performed against ¹⁵O-gas PET and compared with each other.

RESULTS

In qualitative assessments of DSC-CBF maps, Bayesian-CBF maps showed better visualization of decreased CBF on PET (sensitivity = 62.5%, specificity = 100%, positive predictive value = 100%, negative predictive value = 78.6%) than a block-circulant deconvolution method with a fixed noise cutoff and a block-circulant deconvolution method that adopts an oscillating noise cutoff for each voxel according to the strength of noise (P < .03 for all except for specificity). Quantitative analysis of CBF showed that the correlation between Bayesian-CBF and PET-CBF values (ρ = 0.46, P < .001) was similar among the 3 singular value decomposition methods, and Bayesian analysis overestimated true CBF (mean difference, 47.28 mL/min/100 g). However, the correlation between CBF values normalized to the cerebellum was better in Bayesian analysis (ρ = 0.56, P < .001) than in the 3 singular value decomposition methods (P < .02).

CONCLUSIONS

Compared with previously reported singular value decomposition algorithms, Bayesian analysis of DSC perfusion enabled better qualitative and quantitative assessments of CBF in patients with Moyamoya disease.

Intratumoural immune cell landscape in germinoma reveals multipotent lineages and exhibits prognostic significance

AIMS

Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown.

METHODS

We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases.

RESULTS

Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%).

CONCLUSIONS

The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.

Clinical features and mechanistic insights regarding IgG4-related dacryoadenitis and sialoadenitis: a review

Immunoglobulin G4-related disease (IgG4-RD), recognized only recently as a single diagnostic entity, is a chronic inflammatory condition of unknown etiology. The diagnosis of IgG4-RD relies heavily on histopathological analysis and the correlation of histology findings with clinical, serological, and radiological data. CD4⁺ T and B cells, including IgG4-expressing plasmablasts, constitute the major inflammatory cell populations in IgG4-RD and are believed to cause organ damage and tissue fibrosis. Patients with IgG4-RD, who have active, untreated disease, exhibit marked expansion of IgG4-secreting plasmablasts in the blood. Important mechanistic insights correlated with the pathogenesis of IgG4-RD have been disclosed in recent years through the application of novel molecular biology approaches, including next-generation and single-cell RNA sequencing. Exploration of the interactions between these CD4⁺ T cells and cells of the B lymphocyte lineage is critical to understanding the pathophysiology of IgG4-RD. The establishment of pathogenic T cell clones and the identification of antigens specific to these clones constitute the first steps in determining the pathogenesis of this disease. This review focuses on clinical features and mechanistic insights regarding IgG4-related dacryoadenitis and sialoadenitis, from a perspective suitable for oral and maxillofacial surgeons.

Noninvasive Evaluation of CBF and Perfusion Delay of Moyamoya Disease Using Arterial Spin-Labeling MRI with Multiple Postlabeling Delays: Comparison with 15O-Gas PET and DSC-MRI

BACKGROUND AND PURPOSE

Arterial spin-labeling MR imaging with multiple postlabeling delays has a potential to evaluate various hemodynamic parameters. To clarify whether arterial spin-labeling MR imaging can identify CBF and perfusion delay in patients with Moyamoya disease, we compared arterial spin-labeling, DSC, and ¹⁵O-gas PET in terms of their ability to identify these parameters.

MATERIALS AND METHODS

Eighteen patients with Moyamoya disease (5 men, 13 women; ages, 21-55 years) were retrospectively analyzed. CBF values of pulsed continuous arterial spin-labeling using 2 postlabeling delays (short arterial spin-labeling, 1525 ms; delayed arterial spin-labeling, 2525 ms) were compared with CBF values measured by ¹⁵O-gas PET. All plots were divided into 2 groups by the cutoff of time-based parameters (the time of the maximum observed concentration, TTP, MTT, delay of MTT to cerebellum, and disease severity [symptomatic or not]). The ratio of 2 arterial spin-labeling CBFs (delayed arterial spin-labeling CBF to short arterial spin-labeling CBF) was compared with time-based parameters: time of the maximum observed concentration, TTP, and MTT.

RESULTS

The short arterial spin-labeling-CBF values were significantly correlated with the PET-CBF values (r = 0.63; P = .01). However, the short arterial spin-labeling-CBF value dropped in the regions with severe perfusion delay. The delayed arterial spin-labeling CBF overestimated PET-CBF regardless of the degree of perfusion delay. Delayed arterial spin-labeling CBF/short arterial spin-labeling CBF was well correlated with the time of the maximum observed concentration, TTP, and MTT (ρ = 0.71, 0.64, and 0.47, respectively).

CONCLUSIONS

Arterial spin-labeling using 2 postlabeling delays may detect PET-measured true CBF and perfusion delay in patients with Moyamoya disease. Provided its theoretic basis and limitations are considered, noninvasive arterial spin-labeling could be a useful alternative for evaluating the hemodynamics of Moyamoya disease.

Embolisation of a Persistent Primitive Trigeminal Artery for a Large Cavernous Aneurysm

We report a case of large cavernous aneurysm associated with persistent primitive trigeminal artery (PPTA). Thrombosis of the aneurysm was obtained only by occlusion of the PPTA. Aneurysms associated with PPTA have not previously been treated only by the occlusion of PPTA with GDC, and this report presents the first such intervention. A radiological follow-up study with MRI and angiography demonstrated marked shrinkage of the thrombosed aneurysm 17 months later, although clinical symptoms were not improved. From our experience, we suggest that the occlusion of the PPTA can be the first step in the therapeutic protocol for aneurysms associated with PPTA.

Endovascular Treatment of Vein of Galen Aneurysmal Malformations

We report two cases of vein of Galen aneurysmal dilatation (VGAD) and four cases of vein of Galen aneurysmal malformation (VGAM) with special reference to clinical features and therapeutic indications of endovascular treatment.

A case with VGAD was treated by radiosurgery in 1985 with no amelioration to the patient, A case of choroidal type VGAM underwent an operation in 1987, but died of massive hemorrhage 2 years later. The other case of VGAD has been followed-up conservatively.

The remaining cases of VGAM (two choroidal type and one mural type) were treated by endovascular treatment. The two cases of choroidal type were successfully embolized but died of systemic complications, and the only case of mural type was cured.

Recurrent mutations of CD79B and MYD88 are the hallmark of primary central nervous system lymphomas

AIMS

Primary central nervous system lymphoma (PCNSL) manifest aggressive clinical behaviour and have poor prognosis. Although constitutive activation of the nuclear factor-κB (NF-κB) pathway has been documented, knowledge about the genetic alterations leading to the impairment of the NF-κB pathway in PCNSLs is still limited. This study was aimed to unravel the underlying genetic profiles of PCNSL.

METHODS

We conducted the systematic sequencing of 21 genes relevant to the NF-κB signalling network for 71 PCNSLs as well as the pyrosequencing of CD79B and MYD88 mutation hotspots in a further 35 PCNSLs and 46 glioblastomas (GBMs) for validation.

RESULTS

The results showed that 68 out of 71 PCNSLs had mutations in the NF-κB gene network, most commonly affecting CD79B (83%), MYD88 (76%), TBL1XR1 (23%), PRDM1 (20%) and CREBBP1 (20%). These mutations, particularly CD79B and MYD88, frequently coincided within each tumour in various combinations, simultaneously affecting diverse pathways within the network. No GBMs had hotspot mutation of CD79B Y196 and MYD88 L265.

CONCLUSIONS

The prevalence of CD79B and MYD88 mutations in PCNSLs was considerably higher than reported in systemic diffuse large B-cell lymphomas. This observation could reflect the paucity of antigen stimuli from the immune system in the central nervous system (CNS) and the necessity to substitute them by the constitutive activation of CD79B and MYD88 that would initiate the signalling cascades. These hotspot mutations may serve as a genetic hallmark for PCNSL serving as a genetic marker for diagnose and potential targets for molecular therapy.

The diagnostic utility of biopsies from the submandibular and labial salivary glands in IgG4-related dacryoadenitis and sialoadenitis, so-called Mikulicz's disease

IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS) is characterized by serum IgG4 elevation and the infiltration of IgG4-positive plasma cells in glandular tissues. For definitive diagnosis of IgG4-DS, biopsies of local lesions are recommended to exclude Sjögren's syndrome (SS), malignant tumours, and similar disorders. In this study, we examined the diagnostic utility of submandibular gland (SMG) and labial salivary gland (LSG) biopsies in IgG4-DS. Fourteen patients presenting with swelling of the SMG (eight females and six males) underwent both SMG and LSG biopsies. The sensitivity, specificity, and accuracy of SMG biopsies were all 100.0%. In contrast, those of LSG biopsies were 69.2%, 100.0%, and 71.4%, respectively. Thirty-three out of 61 LSG biopsies (54.1%) from all 14 patients were positive for the diagnostic criteria of IgG4-DS (IgG4-positive/IgG-positive plasma cells >0.4). None of the patients experienced complications such as facial nerve palsy, sialocele, or hyposalivation. The IgG4/IgG ratio showed no significant correlation between the LSG and SMG. The final diagnosis was IgG4-DS in 13 patients and marginal zone B-cell lymphoma (MZL) in one. These results suggest that incisional biopsy of the SMG is useful and appropriate for the definitive diagnosis of IgG4-DS, while diagnosis by LSG biopsy alone requires more caution.

Clinical relevance of Küttner tumour and IgG4-related dacryoadenitis and sialoadenitis

Objectives

Küttner tumour (KT), so-called chronic sclerosing sialoadenitis, is characterised by concomitant swelling of the submandibular glands secondary to strong lymphocytic infiltration and fibrosis independent of sialolith formation. However, recent studies have indicated that some patients with KT develop high serum levels of IgG4 and infiltration of IgG4-positive plasma cells, namely IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS), so-called Mikulicz's disease. The aim of this study was to clarify the clinical and pathological associations between KT and IgG4-DS.

Materials and Methods

Fifty-four patients pathologically diagnosed with KT or chronic sialoadenitis were divided into two groups according to the presence or absence of sialolith (KT-S (+) or KT-S (−), respectively).

Results

There were no significant differences in the clinical findings, including the mean age, sex and disease duration, between the two groups. All patients in the KT-S (+) group showed unilateral swelling without infiltration of IgG4-positive plasma cells or a history of other IgG4-related diseases (IgG4-RD), while those in the KT-S (−) group showed bilateral swelling (37.5%), strong infiltration of IgG4-positive plasma cells (87.5%) and a history of other IgG4-RD (12.5%).

Conclusions

These results suggest an association between the pathogeneses of KT-S (−) and IgG4-DS, but not KT-S (+).

Selective localization of T helper subsets in labial salivary glands from primary Sjögren's syndrome patients

The aim of this study was to investigate the initiation and progression of autoimmune damage in the lesions of labial salivary glands (LSGs) from primary Sjögren's syndrome (SS) patients by examining the selective localization of T helper (Th) subsets such as Th1, Th2, Th17 regulatory T cells (T_regs) and follicular T helper cells (Tfh). The expression of cytokines and transcription factors associated with these Th subsets in the LSGs from 54 SS patients and 16 healthy controls was examined using real-time polymerase chain reaction (PCR) and immunostaining. Additionally, infiltrating lymphocytes without germinal centre (GC^-) and with GC (GC⁺) in the LSGs specimens from eight SS patients were extracted selectively by laser capture microdissection (LCM). The mRNA expression of these molecules was compared between the two sample groups of GC^- and GC⁺ by real-time PCR. The mRNA expression of cytokines and transcription factors of all T helper (Th) subsets in the LSGs from the SS patients was increased significantly in comparison with controls. In LSGs from the SS patients, Th2 and Tfh was associated closely with strong lymphocytic infiltration; however, Th1, Th17 and T_regs was not. In the selectively extracted lesions of LSGs, Th1 and Th17-related molecules were detected strongly in the GC^-, while Th2 and Tfh-related molecules were detected in the GC⁺. In contrast, no significant association with strong lymphocytic infiltration was observed in T_reg-related molecules. These results indicate that SS has selective localization of Th subsets such as Th1, Th2, Th17 and Tfh in the LSGs, which is associated closely with disease severity and/or status. SS might be initiated by Th1 and Th17 cells, and then progressed by Th2 and Tfh cells via GC formation.

Cytokine/chemokine profiles contribute to understanding the pathogenesis and diagnosis of primary Sjögren's syndrome

To investigate the pathogenesis of localized autoimmune damage in Sjögren's syndrome (SS) by examining the expression patterns of cytokines, chemokines and chemokine receptors at sites of autoimmune damage. mRNA expression of these molecules in the labial salivary glands (LSGs) and peripheral blood mononuclear cells (PBMCs) from 36 SS patients was examined using a real-time polymerase chain reaction-based method. Subsets of the infiltrating lymphocytes and chemokines/chemokine receptors expression in the LSG specimens were examined by immunohistochemistry. Cytokines/chemokine concentrations in the saliva were analysed using flow cytometry or enzyme-linked immunosorbent assay. mRNA expression of T helper type 1 (Th1) cytokines, chemokines and chemokine receptors was higher in LSGs than in PBMCs. In contrast, mRNA expression of Th2 cytokines, chemokines [thymus and activation-regulated chemokine (TARC/CCL17), macrophage-derived chemokine (MDC/CCL22)] and chemokine receptor (CCR4) was associated closely with strong lymphocytic accumulation in LSGs. Furthermore, TARC and MDC were detected immunohistochemically in/around the ductal epithelial cells in LSGs, whereas CCR4 was detected on infiltrating lymphocytes. The concentrations of these cytokines/chemokines were significantly higher in the saliva from SS patients than those from controls, and the concentrations of Th2 cytokines/chemokines were associated closely with strong lymphocytic accumulation in LSGs. These results suggest that SS might be initiated and/or maintained by Th1 and Th17 cells and progress in association with Th2 cells via the interaction between particular chemokines/chemokine receptors. Furthermore, the measurement of cytokines/chemokines in saliva is suggested to be useful for diagnosis and also to reveal disease status.

Development of ti-coated ferromagnetic needle, adaptable for ablation cancer therapy by high-frequency induction heating

To develop a novel ablation therapy for human solid cancer, the heating properties of a ferromagnetic carbon steel rod and a prototype Ti-coated needle using this carbon steel rod, were investigated in several high-frequency outputs at 300 kHz. In the former, the heating property was drastically different among the three inclination angles (θ = 0°, 45° and 90°) relative to the magnetic flux direction as a result of the shape magnetic anisotropy. However, the effect of the inclination angles was completely eliminated in the latter. It is considered that the complete non-oriented heating property relative to the magnetic flux direction allows the precise control of the ablation temperature during minimally invasive thermotherapy without a lead-wire connected to a fiber-optic thermometer. This newly designed Ti-coated device will be suitable for clinical use combined with its superior biocompatibility for ablation treatments using high-frequency induction heating.

Effects of an immuno-enhanced diet containing antioxidants in esophageal cancer surgery following neoadjuvant therapy

Neoadjuvant therapy-induced immunological deterioration may be a key factor in postoperative morbidity in patients with esophageal cancer. This study aimed to determine the effects of perioperative feeding with an immuno-enhanced diet on immune competence in patients treated with neoadjuvant therapy followed by surgery. Because an immuno-enhanced diet that contained several antioxidants was used, perioperative oxidative stress and the effects of the immuno-enhanced diet on this stress were also investigated. Of 39 patients with esophageal cancer who underwent similar surgical procedures, 26 patients who received chemotherapy or chemoradiation therapy before surgery were randomly divided into two groups: group 1 (n= 14) was given an immuno-enhanced diet for 5 days before surgery, and group 2 (n= 12) received no enteral feeding products before surgery. Group 3 (n= 13) consisted of patients that did not receive neoadjuvant therapy and received no enteral feeding products before surgery. Several markers for coagulation and fibrinolysis were determined and immunological assessments were performed for each patient. To measure reactive oxygen metabolites and the total antioxidant capacity, diacron-reactive oxygen metabolites (d-ROMs) and OXY-adsorbent tests were performed using a free radical elective evaluator. Significant depression in lymphocyte numbers was observed in groups 1 and 2 before and early after surgery as compared to group 3. Numbers of B cells, CD4/CD8 ratio, and phytohemagglutinin-induced lymphocyte transformation tests were also significantly decreased in groups 1 and 2 on postoperative day 1. Fibrin and fibrinogen degradation products were significantly elevated in group 2 compared to group 1. d-ROMs and OXY-adsorbent test values were elevated before surgery and were decreased transiently early after surgery. Compared to groups 2 and 3, d-ROMs values were significantly lower in group 1 patients throughout the postoperative period, while OXY-adsorbent test values were significantly higher in group 2 patients. Oxidative index was significantly suppressed in group 1 compared to group 3. No significant intergroup differences were observed with regard to morbidity after surgery. Although the baseline levels of immunological function might have been different because of less-advanced cancer stages in group 3, neoadjuvant therapy significantly affected several immunological parameters. Preoperative administration of an immuno-enhanced diet did not significantly prevent neoadjuvant therapy-induced immunological deterioration prior to esophageal cancer surgery. Patients with esophageal cancer had elevated levels of oxidant and antioxidant activities before surgery, which were transiently decreased early after surgery. Although the underlying mechanisms for these perioperative changes are unclear, this study showed that an immuno-enhanced diet containing several antioxidants may reduce oxidative stress following esophageal cancer surgery. After these mechanisms are studied further, oxidative stress control may become another tool for perioperative management to reduce morbidity after esophageal cancer surgery.

Tumor local chemohyperthermia using docetaxel-embedded magnetoliposomes: Interaction of chemotherapy and hyperthermia

BACKGROUND AND AIM

We have studied and reported the usefulness of tumor local chemohyperthermia at a low-grade temperature below 43°C with docetaxel-embedded magnetoliposome (DML) and an applied alternating current magnetic field. However, the mechanisms of this treatment and the dynamics of the injected docetaxel were not investigated in our previous study. Thus, we investigated the interaction of chemotherapy and hyperthermia in the treated tumor.

METHODS

Human MKN45 gastric cancer cells were implanted in the hind limbs of Balb-c/nu/nu mice. DML, magnetite-loaded liposome, and docetaxel were injected into the tumors with or without being exposed to an alternating current magnetic field. Docetaxel and tumor necrosis factor-α concentrations, the cell cycle, and cell death rates in the tumor were examined.

RESULTS

Docetaxel concentrations were significantly higher in the DML-injected group than in the docetaxel-injected group 3 days after injection. A G2/M peak was observed 1 day after treatment in the DML-injected and exposed group and the docetaxel-injected group, while it was observed 3 days after treatment in the DML-injected without heating group and the magnetite-loaded liposome group. The tumor cell death rate gradually increased in the DML-injected group, with or without being exposed, while it gradually decreased after its peak in other groups. The tumor necrosis factor-α concentration in the tumor treated with DML with heating remained at a high level on the 7th day after treatment, while it decreased after its peak in other groups.

CONCLUSION

The antitumor effect of this treatment derives from a combination of hyperthermia and chemotherapy locally in the tumor.

[Surgical treatment and outcome of multiple primary lung cancers]

We assessed the selection of the type of pulmonary resection, operative morbidity, mortality and the outcome of our 14 cases who underwent surgical treatment for multiple primary lung cancer. Eleven cases underwent lobectomy with limited surgery, 3 cases underwent combination of limited surgery. Only 1 case had prolonged air leakage after surgery, but other cases had no postoperative complication and there was no operative death. The survival rate was higher than that of T4 (metastasis to the same lung lobe) cases and M1 (metastasis to another lung lobes) cases. With this result, we consider that postoperative good survival can be expected by the aggressive surgical approach for cases of multiple primary lung cancer, despite it is difficult to distinguish multiple primary lung cancers and metastatic cancers preoperatively. On the other hand, the opportunity to treat early-stage lung cancer is possibly increase with the spread of medical checkup using computed tomography (CT), it will be necessary to introduce limited surgery at 1st operation to keep post-operative pulmonary function, considering another surgery for the 2nd primary lung cancer.

Degradation of methylene blue by radio frequency plasmas in water under ultraviolet irradiation

The degradation of methylene blue by radio frequency (RF) plasmas in water under ultraviolet (UV) irradiation was studied experimentally. When the methylene blue solution was exposed to RF plasma, UV irradiation from a mercury vapor lamp enhanced degradation significantly. A lamp without power supply also enhanced degradation since weak UV light was emitted weakly from the lamp due to the excitation of mercury vapor by stray RF power. Such an enhancement is explained by the fact that after hydrogen peroxide is produced via the recombination process of OH radicals around the plasma, OH radicals reproduced from hydrogen peroxide via the photolysis process degrade methylene blue.

Experimental evaluation of photocrosslinkable chitosan hydrogel as injection solution for endoscopic resection

BACKGROUND AND STUDY AIMS

Saline as an injection solution for endoscopic resection techniques has several disadvantages such as a short-lasting effect leading to a potentially higher risk of bleeding and perforation. The new substance of photocrosslinkable chitosan hydrogel in a DMEM/F12 medium (PCH) can be converted into an insoluble hydrogel by ultraviolet irradiation for 30 s, and was evaluated in two sets of animal experiments.

METHODS

18 pigs were used in the two parts of the study. First, mucosal resections were done with either PCH or hypertonic saline; the effects of both agents on wound healing were examined endoscopically and histologically. Second, in vivo degradation of PCH was examined using six pig stomachs.

RESULT

PCH injection led to a longer-lasting elevation with clearer margins, compared with hypertonic saline, thus enabling precise endoscopic submucosal dissection (ESD) along the margins of the elevated mucosa. The endoscopic appearance after ESD was similar in both groups. PCH biodegradation was completed within 8 weeks according to endoscopic and histologic analyses.

CONCLUSION

PCH is a promising agent for submucosal injection prior to various techniques of endoresection. It should be evaluated in clinical trials after biocompatibility testing for PCH is completed.

Novel tumor-ablation device for liver tumors utilizing heat energy generated under an alternating magnetic field

BACKGROUND AND AIMS

We have developed a novel tumor-ablation device for liver tumors utilizing heat energy induced by magnesium ferrite (MgFe(2)O(4)) particles under an alternating magnetic field (AMF) produced by electric currents. This novel device can repeatedly heat liver tumors at lower temperature than usual heating devices, such as radiofrequency ablation therapy, with slight infliction of pain. This study assesses its heating effect on rat liver tumors as local therapy.

METHOD

The small needle was manufactured from MgFe(2)O(4) particles by sintering at 1100 degrees C. After a MgFe(2)O(4) needle was inserted into liver tumors comprising of dRLh-84 cells, the tumors were heated for 30 min under an AMF. We examined cellular activity by using nicotinamide adenine dinucleotide (NADH) diaphorase staining and terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling (TUNEL) staining, and evaluated the effect of suppressing tumor growth by sequentially comparing the tumor diameter with that of the control group.

RESULTS

The mean temperature of the heated tumors was 60.2 +/- 1.8 degrees C. The tumor cells were constricted, and chromatin of nuclei had shrunk immediately after heating. The heat-injury area that contained the tumors was negative for NADH diaphorase activity. After 3 days, the tumor cells in the heat-injury area became positive for TUNEL staining, which detects cell death. At 7 days, the mean tumor diameters were significantly smaller in the heating group than in the control group (6.15 +/- 0.47 mm vs 16.89 +/- 2.69 mm; P < 0.05).

CONCLUSION

This device, utilizing heat energy induced by ferromagnetic metal under an AMF, appears useful as local thermotherapy for human liver cancer.

Feasibility of induction heating using a sintered MgFe2O4 needle for minimally invasive breast cancer therapy

BACKGROUND

This study investigated a novel approach for tumor ablation therapy using an alternating magnetic field combined with a sintered MgFe2O4 needle. This method differs from radiofrequency ablation (RFA) by dielectric heating with regard to the heating mechanism and improves some weak points of these conventional thermotherapies.

MATERIALS AND METHODS

Nude mice mimicking human breast cancer BT474 were treated using this method. The extent of tumor death was assessed after ablation.

RESULTS

Staining with hematoxylin and eosin showed gradual expansion of the pyknotic area until 48 h after ablation. Nicotinamide adenine dinucleotide diaphorase staining also showed complete tumor death by 48 h after treatment. The ablation area was well controlled and reablation was not necessary. The tumor could be completely controlled using this method without any risk of skin burn.

CONCLUSION

This novel ablation therapy appeared to be more effective and less invasive for treatment of breast cancer treatment than RFA.

A supercritical carbon dioxide plasma process for preparing tungsten oxide nanowires

A supercritical carbon dioxide (CO(2)) plasma process for fabricating one-dimensional tungsten oxide nanowires coated with amorphous carbon is presented. High-frequency plasma was generated in supercritical carbon dioxide at 20 MPa by using tungsten electrodes mounted in a supercritical cell, and subsequently an organic solvent was introduced with supercritical carbon dioxide into the plasma. Electron microscopy and Raman spectroscopy investigations of the deposited materials showed the production of tungsten oxide nanowires with or without an outer layer. The nanowires with an outer layer exhibited a coaxial structure with an outer concentric layer of amorphous carbon and an inner layer of tungsten oxide with a thickness and diameter of 20-30 and 10-20 nm, respectively.

Submucosal injection, for endoscopic mucosal resection, of photocrosslinkable chitosan hydrogel in DMEM/F12 medium

BACKGROUND AND STUDY AIMS

We studied the ability of a photocrosslinkable chitosan in DMEM/F12 medium to maintain submucosal thickness and to reduce bleeding after mucosal resection. We also investigated the behavior of chitosan hydrogels with regard to wound healing.

METHODS

The gastric submucosal layer of heparinized rats was injected with the photocrosslinkable chitosan in medium (which was then irradiated with ultraviolet light to form a hydrogel), or with sodium hyaluronate, or hypertonic saline, and three investigations were done, using three different sets of rats. The first and second were measurement of the thickness of the layer, and of the amount of bleeding induced by mucosal resection, respectively. Thirdly, the effects of the chitosan hydrogel on wound healing were examined histologically.

RESULTS

Gastric submucosal layers of chitosan hydrogel-treated animals remained significantly thicker than those of other groups for at least 6 h after injection. The total amount of bleeding 20 min after mechanical mucosal resection was 170.0 +/- 20.0 mg, 678.3 +/- 226.3 mg, and 1020.0 +/- 104.1 mg in the chitosan hydrogel, sodium hyaluronate, and hypertonic saline groups, respectively. Histological study revealed that the focus of bleeding was surrounded by chitosan hydrogel and that almost all the hydrogel was biodegraded within 4 weeks. Furthermore, a discernible, but not statistically significant effect of the chitosan hydrogel on wound healing was observed.

CONCLUSIONS

The chitosan hydrogel produced mucosal elevation after submucosal injection with ultraviolet irradiation, and it significantly reduced bleeding after mucosal resection. Our newly developed chitosan hydrogel in medium might be a promising submucosal agent for endoscopic mucosal resection.

Reduction rate of lymph node metastasis as a significant prognostic factor in esophageal cancer patients treated with neoadjuvant chemoradiation therapy

Tumor regression is used widely as a measure of tumor response following radiation therapy or chemoradiation therapy (CRT). In cases of esophageal cancer, a different pattern of tumor shrinkage is often observed between primary tumors and metastatic lymph nodes (MLNs). Regression of MLNs surrounded by normal tissue may be a more direct measure of the response to CRT than regression of a primary tumor as exfoliative mechanical clearance does not participate in shrinkage of MLNs. In this study we evaluated the significance of the reduction rate (RR) of MLNs as a prognostic factor in esophageal cancer patients treated with neoadjuvant CRT. Forty-two patients with marked MLNs were selected from 93 patients with esophageal carcinoma who had received neoadjuvant CRT. The RRs of the primary tumor and the MLNs were calculated from computed tomography scans. In 20 patients, surgical resection was carried out following CRT. Univariate analysis was used to determine which of the following variables were related to survival: size of the primary tumor and MLNs; RRs of both lesions; degree of lymph node (LN) metastasis; clinical stage; and surgical resection. Multivariate analysis was then performed to assess the prognostic relevance of each variable. The primary tumor was larger than the MLNs in 69% of patients before CRT and in 40% of patients after CRT. In 79% of the patients, the RR of the primary tumor was greater than the RR of the MLNs. The results of the univariate analyses showed that a high RR of the MLNs and surgical resection after CRT were associated with significantly improved survival. The multivariate analysis demonstrated that the RR of MLNs had the strongest influence on survival. The RR of LN metastasis should be evaluated as an important prognostic predictor in patients with marked LN metastasis of esophageal cancer treated with CRT.

[Castleman's disease in the interlobar fissure resected by video-assisted thoracoscopic surgery; report of a case]

An abnormal shadow was detected on the chest X-ray of a 33-year-old man in a medical check-up. Chest computed tomography (CT) showed a 2 x 2 x 3 cm tumor which was enhanced, round, homogeneous, and adjacent to the pulmonary artery in the right interlobar fissure. Video-assisted thoracoscopic surgery was performed in August 2002 for diagnosis and treatment. The tumor was surgically removed and grossly round, elastic and hard. The histopathological diagnosis was hyaline vascular type of Castleman's disease. Postoperative course was uneventful, and the patient was discharged on the third postoperative day. Interlobar Castleman's disease successfully resected by video-assisted thoracoscopic surgery is rare.

Staple line coverage with absorbable mesh after thoracoscopic bullectomy for spontaneous pneumothorax

BACKGROUND

Thoracoscopic simple bullectomy for primary spontaneous pneumothorax (PSP) has a relatively high postoperative recurrence rate and sometimes results in postoperative air leakage. One of the reasons for postoperative recurrence is the regrowth of bullae around the staple line. Therefore, reinforcement of the visceral pleura around the staple line is a reasonable way to prevent postoperative air leaks and recurrence. This study was done to determine the efficacy in preventing postoperative air leak and recurrent pneumothorax of widely covering the staple line with absorbable mesh after thoracoscopic bullectomy.

METHODS

Wide coverage of the staple line with absorbable mesh was performed on 114 patients with PSP. These patients were retrospectively compared with 126 patients who underwent thoracoscopic simple bullectomy alone.

RESULTS

The postoperative duration of chest drainage in the coverage group (mean, 1 day; range, 0-5) was significantly shorter than that in the simple bullectomy group (mean, 3 days; range 0-20). A prolonged air leak (>7 days) occurred in six patients in the simple bullectomy group, but there were no such leaks in the coverage group. Recurrent pneumothorax occurred in three patients (2.6%) in the coverage group and 12 patients (9.5%) in the simple bullectomy group.

CONCLUSION

Wide coverage of the staple line with absorbable mesh is effective in preventing postoperative air leak and in decreasing the recurrence rates of PSP.

Spontaneous subacute intratumoral hemorrhage of hepatic cavernous hemangioma

We report a case of giant hepatic cavernous hemangioma associated with spontaneous subacute intratumoral hemorrhage. Magnetic resonance imaging showed an oval, homogeneous, high-intensity lesion with a low-intensity rim in the original high-intensity tumor on T2-weighted images. On T1-weighted images, this oval lesion showed heterogeneous high intensity with peripheral higher intensity. The histologic specimen confirmed hepatic hemangioma with intratumoral hemorrhage.

Management of branch duct-type intraductal papillary mucinous tumor of the pancreas based on magnetic resonance imaging

BACKGROUND

We assessed the usefulness of magnetic resonance imaging (MRI) in identifying nonmalignant intraductal papillary mucinous tumors (IPMTs) of the pancreas.

METHODS

Thirty-three patients with branch duct-type IPMT diagnosed by endoscopic retrograde cholangiopancreatography were prospectively examined with magnetic resonance cholangiopancreatography followed by dynamic gadolinium-enhanced MRI examinations, and patients with no findings suggestive of malignancy, including a solid mass, mural nodules, a main pancreatic duct wider than 5 mm in diameter, and stenosis of the main pancreatic duct, were prospectively followed up with sequential MRI examinations once or twice a year.

RESULTS

Twenty-six (79%) patients showed no findings suggestive of malignancy in the initial MRI examination. The diameter (mean +/- standard error) of the main pancreatic duct was 3.9 +/- 0.7 mm and that of the ectatic branch pancreatic duct was 36.0 +/- 9.1 mm. Twenty-three patients were prospectively followed for more than 36 months and 22 of them showed no findings suggestive of malignancy during follow-up periods ranging from 39 to 77 months (mean = 55 months).

CONCLUSION

MRI was useful to identify nonmalignant IPMTs of the branch duct type, and close follow-up observation with serial MRI examinations may be appropriate in the management of such patients.

[Intraoperative conversion and postoperative complication of video-assisted thoracoscopic surgery lobectomy for primary lung cancer]

By 2002, we had attempted video-assisted thoracoscopic surgery (VATS) lobectomy or segmentectomy for 140 primary lung cancer cases. Four cases (2.9%) were converted to standard posterolateral thoracotomy for oncologic reasons and aortic injury, and 7 cases (5%) were converted to minithoracotomy with a 10 cm incision due to almost injuring the vascular system. Average blood loss in these cases was 379 ml, and there was no blood transfusion required. Seven of these 11 cases had true pleural symphysis in the thoracic cavity. The remaining 129 cases, consisted of 93 lobectomies and 34 segmentectomies, performed with a minithoracotomy of 5 cm using 2 ports. Average surgical duration was 227 minutes, and blood loss was 100 ml. Postoperative complication occurred in 15 patients (11.6%). Major complications included 1 broncho-pleural fistula, 1 pulmonary infarction, 1 cerebral infarction and 1 respiratory failure needed for mechanical ventilation. However, there were no hospital deaths. The mean postoperative hospital stay was 12 days. We recommend that surgeons should pay attention to hilar dissection, particularly in the presences of adhesion and carefully judge whether to convert to thoracotomy at the time of hemorrhage. The VATS procedure has a low mortality and morbidity for lung cancer, but particulaly in high risk patients, requires care and management the same as an open thoracotomy.

Comparison of 99mTc-MIBI uptakes on planar images with those in excised rats organs

The precision with which images reflect tracer uptake in the myocardium has been studied. Additionally, the degree to which Tc methoxyisobutylisonitrile (99mTc-MIBI) in the liver gave the effect to a myocardial image has been examined. After administering Tc-MIBI to normal male rats, we compared the myocardial uptakes obtained using a gamma camera with the actual uptakes in the excised organs. Twenty-nine rats were used. Following imaging, the anterior view at 5, 10, 15, 30, 45, 60, 90 and 120 min after administration of the tracer, uptakes in the heart, lung, liver and blood were estimated with a well-type scintillation counter (WC) and represented as the percentage of the injected dose per gram of tissue (%ID/g). The regions of interest (ROIs) were placed on planar images (PI) and the uptake in each organ was estimated as the percentage of the injected dose per pixel (%ID/pixel). The ratios of PI-to-WC and heart-to-organ were also evaluated. Cardiac uptake with WC was maximum (1.581%+/-1.893%) at 10 min post-injection. On the other hand, that with PI was maximum (1.493%+/-0.598%) at 45 min post-injection, but there were significant differences between both measurements (PI/WC ratio: about 1.0 time). Pulmonary uptake with WC was the maximum at 5 min (0.808%+/-0.015%) post-injection, and decreased gradually. PI measurement showed the maximum value at 45 min (0.760%+/-0.012%). Hepatic uptake with WC was the maximum at 30 min (0.594%+/-0.254%). On the other hand, PI measurement showed the same pattern with WC, but these values were higher value than WC as the whole. PI measurement showed higher uptakes in each organ than WC measurement. It was concluded that uptakes or the heart-to-organ ratio obtained clinically with PI might not represent a value that is always accurate.