The Role of Cyberknife Radiosurgery/Radiotherapy for Brain Metastases of Multiple or Large-Size Tumors

OBJECTIVE

Focused, highly targeted radiosurgery and fractionated radiotherapy using the Cyberknife are useful treatments for multiple or large metastases. Here we present our results of Cyberknife radiosurgery for 71 patients with 148 metastatic brain lesions.

METHODS

There were 32 women and 39 men with a median age of 63 (range: 30-88) years. Radiographic follow-up was available for 60 patients with 104 lesions. The mean and median initial volumes of the tumor per lesion were 6.6 and 2.9 cm(3) (range: 0.1-53.2 cm(3)), respectively, at the time of the initial Cyberknife treatment. Forty patients (56%) had a single lesion, and 31 (44%) had multiple lesions (range: 2-7) at initial treatment. The number of fractions ranged from 1 to 3, and forty (27%) of 148 lesions were treated by a fractionated course of Cyberknife therapy. The mean marginal dose was 20.2 Gy (range 7.8-30.1 Gy, median: 20.7 Gy).

RESULTS

At 44 weeks of median follow-up, there were no permanent symptoms resulting from radiation necrosis. Overall 6-month and 1-year survival rates were 74% and 47%, respectively, and the median survival time was 56 weeks. The Karnofsky performance score and extracranial metastasis were significant prognostic factors at 6 months and 1 year, respectively, in both univariate and multivariate analyses. Age or multiple metastases did not influence prognosis at 6 months and 1 year. Local control was achieved in 83% (86 lesions). After additional radiosurgical or surgical salvage, no patient died as a result of intracranial disease. Twenty-five patients developed 92 new metastases (range 1-13) outside of the treated lesions with 22.4 weeks of median follow-up. Among them, 21 patients (84 lesions) were treated by salvage Cyberknife.

CONCLUSION

Despite the inclusion of an unfavorable group of patients with large tumors, our results for survival and tumor control rates are comparable to those of published series. The Cyberknife provides the advantage of allowing for fractionated treatment to multiple or large-size tumors.

Different results of the Salmonella umu test between three isomers of phenylenediamine (PDA) derivatives

A post-treatment assay of the umu test was performed to detect genotoxicity of 10 phenylenediamine (PDA) derivatives using Salmonella typhimurium TA1535/pSK1002 with/without S9 mix. Seven chemicals (o-PDA, 4-chloro-o-PDA, 4-nitro-o-PDA, p-PDA, 2-chloro-p-PDA, 2-nitro-p-PDA, and 2,5-diaminotoluene) showed positive results with S9 mix, but three chemicals (m-PDA, 4-chloro-m-PDA, and 2,4-diaminotoluene) were negative with and without S9 mix. Four of 7 chemicals (o-PDA, 4-chloro-o-PDA, 4-nitro-o-PDA, and 2-nitro-p-PDA) that gave positive results with S9 mix were also positive without S9 mix. These results indicate that the genotoxicity of PDA derivative possessing m-position amino substituents was not detected in the umu post-treatment assay using TA1535/pSK1002.

Relationship between apical membrane elasticity and stress fiber organization in fibroblasts analyzed by fluorescence and atomic force microscopy

To investigate the relationship between cellular microelasticity and the structural features of cytoskeletons (CSKs), a microindentation test for apical cell membranes and observation of the spatio-distribution of actin CSKs of fibroblasts were performed by fluorescence and atomic force microscopy (FM/AFM). The indentation depths of apical cell membranes were measured from AFM force-indentation (f-i) curves under equal final loads and mapped two-dimensionally to show the relative distribution of local microelasticity on cell membranes. Intracellular spatial distribution of actin CSKs was visualized fluorescently by high Z-resolution cross-sectional observation of a cell on which indentation mapping analysis had been performed in advance. Structural features of stress fibers (SFs) were observed as three typical patterns of dense SF, sparse SF and sparser SF cell groups, which were quantitated using the degree of orientation in apical SFs (ASFs) that had been defined using two-dimensional Fourier analysis. In indentation depth maps, the upper nuclear region was markedly softer than the pseudopodium region. The mean indentation depth of the upper nuclear region decreased with increased SF density in whole cells and the degree of orientation of ASF, although the pseudopodium region did not exhibit such a trend. The apical membrane of adhered cells was found to tend to stiffen with the increase in both density and degree of orientation of SFs.

CyberKnife Stereotactic Radiotherapy for Patients with Malignant Glioma

OBJECTIVE

The CyberKnife is a new frameless image-guided radiosurgical modality. The authors report on their experience using the CyberKnife in 25 patients with malignant gliomas.

METHODS

Twenty-five patients with histologically proven malignant gliomas (18 glioblastoma: GB, 7 anaplastic astrocytoma: AA) were treated with the CyberKnife at Konan St. Hill Hospital between June 1998 and November 2002. CyberKnife therapy was performed on 44 lesions (31 GB lesions, 13 AA lesions) in the 25 patients. The median target volume was 19.1 mL (range: 0.3 - 90.2). The median prescribed dose was 20.3 Gy (range: 13.9 - 26.4). Patient-, tumor-, and treatment-related variables were analyzed by univariate analysis, and survival curves were generated by the Kaplan-Meier product limit.

RESULTS

In the 18 GB patients, the median survival after diagnosis was 20.7 months (82.6 weeks) with a mean follow-up of 85.7 weeks. Of the 7 AA patients, 6 were alive at the time of analysis with follow-up periods ranging from 11.4 to 52.8 months. Patients younger than 70 years had a median survival after diagnosis of 37.1 months, compared to 12.4 months for older patients (p = 0.003). Similarly, patients with well-controlled lesions had a median survival after diagnosis of 39.8 months compared to 16.0 months for those with uncontrolled lesions (p = 0.031). Late delayed radiation necrosis was seen in 1 GB patient. No other patient suffered acute or delayed neurological morbidity after CyberKnife therapy.

CONCLUSION

This is the first report of CyberKnife stereotactic radiotherapy applied to the treatment of malignant gliomas. The frameless and painless CyberKnife stereotactic radiotherapy has the potential to be as useful for treatment of malignant glioma as other radiosurgical modalities.

Structural transition of actin filament in a cell-sized water droplet with a phospholipid membrane

Actin filament, F-actin, is a semiflexible polymer with a negative charge, and is one of the main constituents of cell membranes. To clarify the effect of cross talk between a phospholipid membrane and actin filaments in cells, we conducted microscopic observations on the structural changes in actin filaments in a cell-sized (several tens of micrometers in diameter) water droplet coated with a phospholipid membrane such as phosphatidylserine (PS; negatively charged head group) or phosphatidylethanolamine (PE; neutral head group) as a simple model of a living cell membrane. With PS, actin filaments are distributed uniformly in the water phase without adsorption onto the membrane surface between 2 and 6 mM Mg2+, while between 6 and 12 mM Mg2+, actin filaments are adsorbed onto the inner membrane surface. With PE, the actin filaments are uniformly adsorbed onto the inner membrane surface between 2 and 12 mM Mg2+. With both PS and PE membranes, at Mg2+ concentrations higher than 12 mM, thick bundles are formed in the bulk water droplet accompanied by the dissolution of actin filaments from the membrane surface. The attraction between actin filaments and membrane is attributable to an increase in the translational entropy of counterions accompanied by the adsorption of actin filaments onto the membrane surface. These results suggest that a microscopic water droplet coated with phospholipid can serve as an easy-to-handle model of cell membranes.

Elongation/compaction of giant DNA caused by depletion interaction with a flexible polymer

Structural changes in giant DNA induced by the addition of the flexible polymer Polyethylene Glycol (PEG) were examined by the method of single-DNA observation. In dilute DNA conditions, individual DNA assumes a compact state via a discrete coil-globule transition, whereas in concentrated solution, DNA molecules exhibit an extended conformation via macroscopic phase segregation. The long-axis length of the stretched state in DNA is about 10(3) times larger than that of the compact state. Phase segregation at high DNA concentrations occurs at lower PEG concentrations than the compaction at low DNA concentrations. These opposite changes in the conformation of DNA molecule are interpreted in terms of the free energy, including depletion interaction.

Comparative analysis of transcriptional responses to saline stress in the laboratory and brewing strains of Saccharomyces cerevisiae with DNA microarray

To construct yeast strains showing tolerance to high salt concentration stress, we analyzed the transcriptional response to high NaCl concentration stress in the yeast Saccharomyces cerevisiae using DNA microarray and compared between two yeast strains, a laboratory strain and a brewing one, which is known as a stress-tolerant strain. Gene expression dynamically changed following the addition of NaCl in both yeast strains, but the degree of change in the gene expression level in the laboratory strain was larger than that in the brewing strain. The response of gene expression to the low NaCl concentration stress was faster than that to the high NaCl concentration stress in both strains. Expressions of the genes encoding enzymes involved in carbohydrate metabolism and energy production in both strains or amino acid metabolism in the brewing strain were increased under high NaCl concentration conditions. Moreover, the genes encoding sodium ion efflux pump and copper metallothionein proteins were more highly expressed in the brewing strain than in the laboratory strain. According to the results of transcriptome analysis, candidate genes for the creation of stress-tolerant strain were selected, and the effect of overexpression of candidate genes on the tolerance to high NaCl concentration stress was evaluated. Overexpression of the GPD1 gene encoding glycerol-3-phosphate dehydrogenase, ENA1 encoding sodium ion efflux protein, and CUP1 encoding copper metallothionein conferred high salt stress tolerance to yeast cells, and our selection of candidate genes for the creation of stress-tolerant yeast strains based on the transcriptome data was validated.

Sensing the distance to a source of periodic oscillations in a nonlinear chemical medium with the output information coded in frequency of excitation pulses

A spatially distributed excitable chemical medium can collect and process information coded in the propagating pulses of excitation. We consider the problem of distance sensing with the use of a nonlinear chemical medium. We demonstrate that a sensor that can feel the distance separating it from a source of periodic excitations can be constructed by a proper geometrical arrangement of excitable and nonexcitable regions. The sensor returns information about the distance in the frequency of outgoing pulses. The sensor functionality is tested by simulations based on the Rovinsky-Zhabotinsky model. The results are confirmed in experiments performed for a ruthenium-catalyzed Belousov-Zhabotinsky reaction.

Different pathways in mechanical unfolding/folding cycle of a single semiflexible polymer

Kinetics of conformational change of a semiflexible polymer under mechanical external field were investigated with Langevin dynamics simulations. It is found that a semiflexible polymer exhibits large hysteresis in mechanical folding/unfolding cycle even with a slow operation, whereas in a flexible polymer, the hysteresis almost disappears at a sufficiently slow operation. This suggests that the essential features of the structural transition of a semiflexible polymer should be interpreted at least on a two-dimensional phase space. The appearance of such large hysteresis is discussed in relation to different pathways in the loading and unloading processes. By using a minimal two-variable model, the hysteresis loop is described in terms of different pathways on the transition between two stable states.

Bone marrow cells differentiate into wound myofibroblasts and accelerate the healing of wounds with exposed bones when combined with an occlusive dressing

BACKGROUND

The usefulness of bone marrow cells in accelerating wound healing has not been evaluated despite increasing evidence that bone marrow contains mesenchymal stem cells that have multipotentiality to differentiate into various types of cells after they enter the microenvironment of a specific tissue (niche).

OBJECTIVES

To determine the effects of bone marrow cells and occlusive dressings in promoting wound healing in rats.

METHODS

We investigated by grafting, biopsy and immunohistochemistry whether various types of cells derived from green fluorescent protein (GFP)-transgenic rats would differentiate into wound component cells when administered topically on the wounds of rats. We also investigated whether topical application of bone marrow cells with an occlusive dressing would accelerate the healing of wounds with exposed bones, as measured by planimetry.

RESULTS

GFP-labelled bone marrow cells contained multipotent stem cells that sufficiently differentiated into wound myofibroblasts presenting with alpha-smooth muscle actin in granulation tissue. Other types of cells, including myocytes, adipocytes, peripheral blood cells from buffy coat and dermal fibroblasts, did not express myofibroblast characteristics morphologically or immunohistochemically. Application of bone marrow cells and an occlusive dressing accelerated the repair of wounds with exposed bones, compared with an occlusive dressing only or with the topical administration of bone marrow cells plus a semidry to dry dressing.

CONCLUSIONS

Our study indicates that bone marrow cells accelerate the healing of wounds at least in part through their differentiation into wound myofibroblasts. Thus, treatment of wounds with bone marrow cells and a supportive occlusive dressing is effective in promoting the formation of healthy granulation tissue and also for the preparation of an ideal wound bed.

Morphological variation in a toroid generated from a single polymer chain

A single semiflexible polymer chain folds into a toroidal object under poor solvent conditions. In this study, we examined the morphological change in such a toroidal state as a function of the cross-sectional area and stiffness of the chain together with the surface energy, which characterizes the segmental interaction parameter. Changes in the thickness and outer/inner radius on a toroid are interpreted in terms of these parameters. Our theoretical expectation corresponds to the actual morphological changes in a single giant DNA molecule as observed by electron microscopy.

Contrast-enhanced dynamic MR imaging parameters and histological types of invasive ductal carcinoma of breast

The diagnosis of breast cancer has progressed owing to the improvement of both MRI equipments and MR techniques. CE-MRI is expected to be more useful for diagnosis of the existence and characteristics of breast cancer than mammography and ultrasound. Forty-three breast cancer patients, who underwent breast MRI examination before surgery and had histologically confirmed invasive ductal carcinomas, were included in this study. In 19, seven and 17 of them, carcinomas were histologically classified as papillotubular, solid-tubular, and scirrhous type, respectively. In dynamic MRI studies, the MR parameters were calculated from the signal intensity determined before and at five time-points after a bolus of 0.1 mmol Gd-DTPA/kg in the chosen region of interest (ROI). The differential analysis of MR parameters with reference to histopathology was performed by one-way analysis of variance (ANOVA) in dynamic studies. Four of 15 parameters analyzed, ENH1-2, ENH1, MSLP, and SAT3, were significantly different between papillotubular and scirrhous carcinoma. The dynamic curve of papillotubular carcinoma reached a maximum in the very early phase and then decreased slowly (linear pattern), while that of scirrhous carcinoma peaked in the slightly later phase and then decreased (parabolic pattern). In the differential analysis by Kruskal-Wallis test, although no significant differences were found in any morphological parameters among three histological types, spicula formation and rim enhancement tended to appear comparatively frequently in scirrhous and solid-tubular carcinoma. CE-MRI might reveal the differences of growth characteristics among different histological types of breast carcinomas and provide a diagnostic method useful for estimation of the prognosis of breast cancer.

Prevention of amputation caused by rheumatic diseases following a novel therapy of exposing bone marrow, occlusive dressing and subsequent epidermal grafting

BACKGROUND

Wounds with exposed bones caused by rheumatic diseases commonly result in amputation despite progress in our understanding of wound-healing mechanisms.

OBJECTIVES

To determine whether an experimental therapy of bone marrow exposure, an occlusive dressing and subsequent grafting of epidermal sheets accelerates healing and reduces the need for amputation in patients with rheumatic diseases.

METHODS

Fifteen patients, including those with rheumatoid arthritis or systemic sclerosis, who had wounds with exposed bones were treated either with the standard procedure, consisting of local wound care, debridement with a scalpel, bed rest and parenteral antibiotics (n = 8), or with a newly developed experimental procedure (n = 7). In that new procedure, the affected bone was initially exposed by debridement with a scalpel, followed by partial excision with a bone scraper until bleeding was observed from the exposed bone. The lesions were immediately covered with an occlusive dressing, and were eventually treated with epidermal grafts obtained from suction blisters.

RESULTS

A comparison with standard therapy demonstrated that the time needed for wound healing was similar, but that the newly developed combination therapy reduced the risk of amputation (P = 0.020). No skin ulcers or erosions were observed for at least 1 year in five of seven patients (72%) due to the adoption of stable palmoplantar-type characteristics in grafts derived from the trunk epidermis.

CONCLUSIONS

Our study indicates that exposure of bone marrow cells plus an occlusive dressing accelerates the healing of skin ulcers at least partly through the preparation of a healthy well-granulated wound bed and that subsequent epidermal grafting achieves site-specific differentiation through epithelial-mesenchymal interactions.

Image-Guided Stereotactic Radiosurgery with the CyberKnife for Pituitary Adenomas

This study demonstrates the clinical usefulness of image-guided fractionated stereotactic radiosurgery with the CyberKnife system. Twenty-one patients with pituitary adenomas received image-guided stereotactic radiosurgery with the CyberKnife, and were followed up for more than 18 months. The patients consisted of 14 with non-functioning adenomas, 3 with prolactinomas, 2 with acromegaly, and 2 with ACTH-producing tumors. In 20 cases, fractionated radiosurgery was performed. The change in the tumor volume, visual acuity, hormonal function, and complications by this therapy were analyzed in each case. The volume of the tumors ranged from 0.2 cm (3) to 34.9 cm (3) (mean +/- SD: 11.3 +/- 9.2 cm (3)). The mean volumes of the non-functioning and functioning adenomas were 13.3 cm (3) and 7.5 cm (3), respectively. The marginal irradiation dose ranged from 6.4 Gy to 27.7 Gy (mean: non-functioning adenomas 12.6 Gy, functioning adenomas 17.5 Gy), as a dose of a single fraction. The follow-up periods ranged from 18 months to 59 months (mean +/- SD: 35.3 +/- 10.7 months). The tumor control rate was 95.2 %. In 1 case, visual acuity worsened due to cystic enlargement of the tumor. Hormonal function improved in all of the 7 functioning adenomas. The hormone level normalized in 1 prolactinoma, and decreased to less than normal in 1 ACTH-producing adenoma. In 2 cases, hypopituitarism occurred after the therapy. Image-guided stereotactic radiosurgery with the CyberKnife is effective and safe against relatively large pituitary adenomas. Careful long-term follow-up of the patients is necessary because of delayed cystic enlargement of the tumor in rare cases.

Rapid healing of intractable diabetic foot ulcers with exposed bones following a novel therapy of exposing bone marrow cells and then grafting epidermal sheets

BACKGROUND

Diabetic foot ulcers with exposed bones commonly result in amputation.

OBJECTIVES

To determine whether exposure of bone marrow cells and subsequent grafting of epidermal sheets accelerates healing and reduces the need for amputation.

METHODS

Thirty-eight patients with chronic wounds caused by diabetes mellitus were enrolled in this study. Epidermal sheets obtained from suction blisters of each patient were grafted on to diabetic foot ulcers without exposed bones (n = 10) and were compared with the standard treatment of local wound care, debridement with a scalpel when indicated, bed rest and parenteral antibiotics (n = 8). In another group of patients, diabetic wounds with exposed bones were treated either with the standard procedure (n = 9) or with a newly developed experimental procedure (n = 11). In that new procedure, the affected bone was initially exposed by debridement with a scalpel, followed by partial excision with a bone scraper until fresh bleeding was observed from the exposed bone. The lesions were then immediately covered with an occlusive dressing, and finally the wound was covered with an epidermal graft of skin harvested from suction blisters. Patients in each group were matched with their counterparts by age, sex, wound size, wound infection and wound duration, to compare the time needed for total skin repair and rates of amputation.

RESULTS

Epidermal grafting significantly accelerated the healing of diabetic foot ulcers (P = 0.042) without exposed bones, with site-specific differentiation. The newly developed combination therapy resulted in the healing of all diabetic ulcers with exposed bones without the occurrence of osteomyelitis or the necessity for amputation (P < 0.0001).

CONCLUSIONS

Our study indicates that early aggressive debridement of diabetic foot ulcers with exposed bones down to a bleeding vascularized base and then grafting epidermal sheets significantly improves healing and reduces the rate of amputation.

Magnetic resonance and biochemical studies during pentylenetetrazole-kindling development: the relationship between nitric oxide, neuronal nitric oxide synthase and seizures

The major aim of this study was to elucidate the role of nitric oxide (NO) in the development of pentylenetetrazole (PTZ)-kindling as an animal model of primary generalized epilepsy. The daily administration of PTZ is associated with an increase in the amount of neuronal nitric oxide synthase (nNOS). NO generation was measured directly by in vivo and ex vivo electron paramagnetic resonance on rodents undergoing progressive convulsions. We found that primary generalized epilepsy is caused by NO induction during the persistent up-regulation of nNOS expression, but that NO induction is not associated with severe generalized seizures following long-term kindling phenomena after PTZ withdrawal. Morphological changes in the brain structure of rats were measured by magnetic resonance imaging during epileptic convulsions induced by repetitive administration of PTZ. Cerebellum volume for kindled rats decreased 20% but not in rats treated with the nNOS inhibitor, 3Br-7NI, suggesting that generation of NO in the cerebellum is related to decrease in cerebellum volume following PTZ-kindling.

MR tractography for the evaluation of functional recovery from lenticulostriate infarcts

OBJECTIVE

To evaluate the anatomic and clinical relationship between the lenticulostriate artery (LSA) territory and the corticospinal tract (CST) in patients with acute infarcts in this territory using MR tractography.

METHODS

Thirteen consecutive patients who presented with acute infarcts in the LSA territory and who also had undergone an MRI study within 3 days after symptom onset were studied. Visualization of the CST was achieved by postprocessing the acquired diffusion tensor imaging data. To classify lesion location, the LSA territory was divided into four subsegments, the boundaries of which were drawn by axial and coronal planes crossing through the foramen of Monro. Infarct volume and extent of CST involvement were measured and compared with neurologic findings.

RESULTS

All of the infarcts were located in the posterior segment. All of the depicted CSTs crossed the LSA territory only at the posterosuperior quadrant. The extent of CST involvement within the infarcts was correlated with the severity of the patient's motor deficit (p < 0.01) and with the clinical outcome (p < 0.05).

CONCLUSIONS

The corticospinal tracts (CSTs) crossed the lenticulostriate artery territory exclusively at the posterosuperior quadrant, and the degree of CST involvement within the infarcts was directly related to stroke severity and functional recovery.

Physical characteristics of low and medium energy collimators for 123I imaging and simultaneous dual-isotope imaging

Septal penetration of high energy photons may degrade 123I images obtained with a low energy collimator. We evaluated the physical characteristics of a low energy, high resolution (LEHR) collimator, special LEHR (SLEHR) collimator, and medium energy collimator for 123I studies. The cross-talk of 99mTc and 123I into the 201Tl window was also examined. Sensitivity and spatial resolution were measured with each collimator. Point sources of 99mTc and 123I were imaged at various source-collimator distances using multiple energy windows, and the effects of collimator choice on energy spectrum and spatial distribution of photopeak counts were assessed. For 99mTc, both sensitivity and resolution were similar with the low energy collimators, and higher sensitivity and lower resolution were observed with the medium energy collimator. For 123I, the full width at tenth maximum was larger for 123I than for 99mTc when using the LEHR collimator. Acquisitions with multiple energy windows revealed severe degradation due to septal penetration in imaging 123I with the LEHR collimator, especially at short distances. The degradation was reduced with the SLEHR collimator and further with the medium energy collimator. In both 99mTc and 123I imaging, cross-talk into the 201Tl window was larger at shorter distances and the largest with the LEHR collimator. In conclusion, variation in collimator geometry causes differences in the effect of septal penetration on 123I images and in cross-talk into the 201Tl window. The SLEHR collimator may be suitable for use in high resolution 123I imaging and simultaneous 99mTc/201Tl imaging. Use of the medium energy collimator appears to be preferable in quantitative 123I studies.

Quantitative evaluation of cerebrovascular reactivity in brain tissue by a refill kinetic method of transcranial ultrasonic perfusion imaging: a comparison with Doppler sonography

To confirm the reliability of a refill kinetic method of ultrasonic harmonic perfusion imaging (HPI) capable of quantifying separate parameters of microvascular blood flow velocity and volume in brain tissue, we evaluated acetazolamide (ACZ) cerebrovascular reactivity by transcranial HPI in comparison with Doppler sonography (TCD). Methods. HPI during continuous Levovist infusion with changing pulsing intervals (t) and TCD time-averaged maximum velocity (TAMX) in the middle and posterior cerebral arteries were evaluated before and after ACZ administration in 12 patients, 8 without and 4 with a temporal skull defect. Plateau value (A) and rise rate (beta) of intensity (I) represented by HPI time-intensity curves of I(t) = A(1 - e(-beta*t)) were analyzed on the axial diencephalic plane.

RESULTS

1) A significantly decreased in proportion to the region of interest location depth only in the intact skull cases. 2) Despite inter- and intra-individual data scattering, in correspondence with TAMX increases after ACZ, significant beta increases were more frequently identified than increases of A.

CONCLUSIONS

Cerebral vasoreactivity analysis utilizing refill kinetics of transcranial HPI can potentially provide separate quantification based on microvascular blood velocity and volume (capillary patency) with consideration of depth-dependant ultrasound attenuation. This should be suitable for bedside evaluation of neurointensive care patients.

CyberKnife Radiosurgery for Vestibular Schwannoma

OBJECTIVE

The CyberKnife is newly developed equipment for radiosurgery and fractionated radiosurgery. The authors report on their experience using the CyberKnife in 38 patients with vestibular schwannoma who were treated between 1998 to 2002.

METHODS

During this period, 38 patients with vestibular schwannoma were treated using CyberKnife fractionated radiosurgery. Before undergoing fractionated radiosurgery, 14 patients had Gardner Robertson classes I or II hearing (the serviceable hearing group), and 24 patients had classes III to V hearing (the non-serviceable hearing group). The treatment volumes of these two groups were 0.5 to 24.0 cm (3) (mean 4.7 cm (3)), and 0.5 to 41.6 cm (3) (mean 8.2 cm (3)). Target irradiation was administered in 1 - 3 fractions (mean 2.5 fractions). The total marginal radiation doses were 15.0 to 20.5 Gy (mean 17.0 Gy), and 11.9 to 20.1 Gy (mean 16.9 Gy), respectively.

RESULTS

After a mean follow-up period of 31.9 months (range 12 to 59 months, median 27 months), 94 % of the tumors were controlled. Only one patient in the group with non-serviceable hearing underwent additional surgical resection for a presumed increase in tumor size. The hearing preservation rate was 93 %. Facial weakness did not develop in any of the patients in the serviceable hearing group. New trigeminal symptoms did not develop in any patients in either group.

CONCLUSION

Although a longer and more extensive follow-up is needed, CyberKnife fractionated radiosurgery is considered to be safe and effective, even in patients with large tumors.

Cyclooxygenase-2 is a possible target of treatment approach in conjunction with photodynamic therapy for various disorders in skin and oral cavity

BACKGROUND

Anti-cancer effects of cyclooxygenase (COX)-2 inhibitors have been reported, but not fully investigated in skin and oral diseases. 5-aminolaevulinic acid (ALA)-based photodynamic therapy (PDT) for treating those patients with skin and oral lesions is a highly sophisticated procedure, but the incidence of disease recurrence after treatment is rather significant.

OBJECTIVE

To confirm that COX-2 could be a molecular target in adjunctive therapy to ALA-based PDT, we investigated (i) COX-2 expression in various skin and oral diseases, and (ii) the inhibitory effects on cellular growth of COX-2 selective inhibitor (nimesulide), ALA-based PDT and their combination on human oral squamous cell carcinoma (SCC) cell lines.

METHODS

A total of 129 biopsy samples from the skin and oral mucosal lesions were tested immunohistochemically for COX-2 expression. Then the in vitro effects of nimesulide, ALA-based PDT, and their combination were determined on two SCC cell lines, HSC-2 and HSC-4. Three different methods (MTT assay, double-staining for annexin V and propidium iodide, caspase-3/CPP32 fluorometric protease assay) were applied for evaluation of their inhibitory effects on these two cell lines.

RESULTS

Among the skin diseases, a considerable number of COX-2 high expressers were found in actinic keratosis (15 of 25, 60%), Bowen's disease (13 of 17, 76%) and extramammary Paget's disease (15 of 15, 100%). In contrast, only one of 33 (3%) basal cell carcinoma tumours was a COX-2 high expresser. Among the oral mucosal biopsies, the proportion of COX-2 high expressers increased gradually from hyperplasia (one of six, 17%) through mild dysplasia (five of eight, 63%) and moderate dysplasia (20 of 23, 87%) to severe dysplasia (two of two, 100%). Nimesulide had an inhibitory effect in vitro on HSC-2 (proven to be a COX-2 high expresser), but not on HSC-4 (a COX-2 non-expresser). While ALA-based PDT showed an inhibitory effect on both HSC-2 and HSC-4, most importantly the combination of nimesulide and ALA-based PDT demonstrated a significant synergistic effect on the cellular growth inhibition of only HSC-2, but not of HSC-4.

CONCLUSIONS

Our study strongly suggests that COX-2 can be one of the molecular targets in treating various skin and oral diseases. The results from our in vitro experiments also prompt us to develop a new protocol with a combination of COX-2 selective inhibitor and ALA-based PDT for more effective treatment of those diseases.

Early pathological changes in the parkinsonian brain demonstrated by diffusion tensor MRI

OBJECTIVE

To determine whether the fractional anisotropy (FA) of magnetic resonance diffusion tensor imaging is decreased in the nigrostriatal projection in parkinsonian patients.

METHODS

FA values were compared in the extrapyramidal system of 12 patients with Parkinson's disease and eight age matched normal controls.

RESULTS

Patients with Parkinson's disease had significantly decreased FA in the region of interest along a line between the substantia nigra and the lower part of the putamen/caudate complex, in which most of the nigrostriatal dopaminergic neurones are included. Loss of FA in this region was obvious even during the early clinical stages of Parkinson's disease.

CONCLUSIONS

Assuming that the loss of FA parallels the neuronal change in the brain, the results are consistent with the view that more than half the dopaminergic neurones in the nigrostriatal projection are lost before the onset of Parkinson's disease. Close comparison of FA in the basal ganglia may contribute to the early diagnosis of Parkinson's disease.

Enhanced CT for initial localization of active lower gastrointestinal bleeding

BACKGROUND

Active lower gastrointestinal (GI) bleeding is a potentially dangerous situation because patients with this condition may fall into shock. Colonoscopy, angiography, and scintigraphy have been used widely to localize the source of bleeding, but time is needed to perform these examinations. The purpose of this study was to illustrate how vividly enhanced computed tomography (CT) may show active lower GI bleeding in a short time.

METHODS

Five of 10 patients with active lower GI bleeding underwent dynamic enhanced CT. Scans were obtained 0.5 and 5 min after intravenous contrast.

RESULTS

Pooling of contrast medium was found in four of five patients. Among the five patients, three had diverticular disease of the colon, one had a rectal ulcer, and one had a small intestinal ulcer. The localization procedure completed within 15 min in all patients. Extravasations of medium were confirmed by two surgeons.

CONCLUSION

Enhanced helical CT was useful for the detection of an active lower GI bleeding source. The procedure was brief, less invasive, and less demanding. Enhanced CT may be the first step for diagnosing lower GI tract bleeding.

Fluorescence microscopic visualization of a DNA-cationic fullerene complex

Cationic fullerene derivative 1, which is soluble in aqueous medium, bound to double stranded DNA. Observation of Coliphage T4 DNA in the absence and presence of 1 by fluorescence microscopy suggested that 1 bound to DNA along its groove. Upon irradiation of visible light on the DNA complex of 1, DNA was cleaved dramatically. The process of DNA photo-cleavage could be monitored continuously by fluorescence microscopy.

Competition between interchain and intrachain phase segregation

Single-molecule observations of giant DNA have clarified that individual molecules undergo a marked discrete transition between an elongated coil state and a compact globule state. There is a relatively wide region of coexistence between the coil and the globule states, i.e., interchain phase segregation, with a change in intensive variables such as the concentration of the condensing agent, salt concentration, temperature. Very recently, the coexistence of coil and globule conformations within a single long DNA chain, i.e., intrachain phase segregation, has been reported under certain experimental conditions. In this study, we investigated general conditions for intrachain phase segregation in a single polyelectrolyte molecule, based on a simple statistical model. We consider the contribution of condensed counterions and the interaction energy of a charged coiled region. Intrachain phase segregation is stable with regard to free energy within a suitable parameter region. Our results suggest that intrachain phase segregation occurs when the electrostatic screening effect by the salt solution is negligible or when the screening effect is large and there is attractive interaction between polyelectrolyte segments.

A case of manganese induced parkinsonism in hereditary haemorrhagic telangiectasia

A 44 year old right handed woman complained of difficulty in moving. She and her relatives had skin telangiectasia or recurrent epistaxis. On neurological examination, she had a mask-like facies and bradykinesia in both extremities. Laboratory examinations showed iron deficiency anaemia and mild liver dysfunction with raised serum manganese. On T1 weighted cranial magnetic resonance imaging there were hyperintense areas in the globus pallidus bilaterally, suggesting manganese deposition. Abdominal angiography confirmed multiple portal-systemic shunts in the liver, and a needle biopsy of the liver showed diffuse dilatation of the sinusoids with fatty change. Levodopa did not improve the bradykinesia. This appears to be a case of hereditary haemorrhagic telangiectasia with manganese induced parkinsonism, which may be a new type of neurological disorder in such patients.

Detection of circulating MN/CA9 positive renal cell carcinoma cells during operation

Our previous study demonstrated the clear detection of MN/CA9 mRNA in peripheral blood samples from RCC patients. However, approximately 30 % of control blood samples from healthy volunteers showed MN/CA9 expression. We have developed a new primer set and optimized the PCR conditions, now resulting in a specificity of 100 %. In tissue samples, all clear cell type carcinomas but none of the spindle cell type and pleomorphic cell type tumors expressed the MN/CA9 message. Analysis of MN/CA9 messages in peripheral blood samples from RCC patients gave positive results for 0/2, 1/9, 0/4 and 4/12 of stage I, II, III and IV cases, respectively. RT-PCR analysis using preoperative renal venous blood samples resulted in clear detection of MN/CA9 positive cells in 2/4, 3/13, 2/6 and 1/1 of stage I, II, III and IV cases, respectively. Our results suggest that assessment of MN/CA9 expression by RT-PCR is a promising method for detecting cancer cells in the circulation of patients with RCC.

Wallerian degeneration of the inferior cerebellar peduncle depicted by diffusion weighted imaging

Wallerian degeneration of the inferior cerebellar peduncle has never been demonstrated on imaging studies. We describe a case in which it was depicted by thin slice diffusion weighted imaging. Location to the inferior cerebellar peduncle was confirmed by a fibre tracking method.

Washout studies of 11C in rabbit thigh muscle implanted by secondary beams of HIMAC

Heavy ion therapy has two definite advantages: good dose localization and higher biological effect. Range calculation of the heavy ions is an important factor in treatment planning. X-ray CT numbers are used to estimate the heavy ion range by looking up values in a conversion table which relates empirically photon attenuation in tissues to particle stopping power; this is one source of uncertainty in the treatment planning. Use of positron emitting radioactive beams along with a positron emission tomograph or a positron camera gives range information and may be used as a means of checking in heavy ion treatment planning. However, the metabolism of the implanted positron emitters in a living object is unpredictable because the chemical forms of these emitters are unknown and the metabolism is dependent on the organ species and may be influenced by many factors such as blood flow rate and fluid components present. In this paper, the washout rate of 11C activity implanted by injecting energetic 11C beams into thigh muscle of a rear leg of a rabbit is presented. The washout was found to consist of two components, the shorter one was about 4.2 +/- 1.1 min and the longer one ranged from 91 to 124 min. About one third of the implanted beta+ activity can be used for imaging and the rest was washed out of the target area.

Interaction of double-stranded T4 DNA with cationic gel of poly(diallyldimethylammonium chloride)

Interaction between duplex T4 DNA and a slightly cross-linked cationic gel of poly(diallyldimethylammonium chloride) in aqueous media was studied by fluorescent microscopy. While short DNA chains such as plasmid DNAs penetrate into the gel and form a phase of polyelectrolyte complex with the cationic network, the genomic giant DNA chains of T4 phages form complexes only on local areas of the gel surface. The DNA/gel complex exhibited different characteristic morphologies depending on the conditions for preparing the complex, such as the DNA concentration, flux of the solution, and surface geometry of the gel: (1) In the interaction with the flat surface of film-type gel, compact round objects, which reflected a condensed state of single DNA chains, were observed. (2) In the interaction with partly dried gel, a characteristic pattern similar to propagating waves was formed on the gel surface. (3) When flux is generated for a concentrated DNA solution, long oriented fiberlike structures were formed, which consisted of ensembles of chains. The interaction with small pieces of mechanically decomposed gel leads to complete covering of their surface by the DNA.

Epidermal expression of serine protease, neuropsin (KLK8) in normal and pathological skin samples

AIMS

The expression of human neuropsin (KLK8) mRNA in normal and pathological skin samples was analysed and the results compared with those for tissue plasminogen activator (tPA) mRNA.

METHODS

Northern blot and in situ hybridisation analyses of KLK8 mRNA in normal and lesional skin of patients with cutaneous diseases were performed.

RESULTS

A weak signal for KLK8 mRNA and no signal for tPA mRNA was seen in normal skin on northern blot analysis. Weak signals for KLK8 were localised to the superficial cells beneath the cornified layer in normal skin on in situ hybridisation. Psoriasis vulgaris, seborrheic keratosis, lichen planus, and squamous cell carcinoma skin samples, which show severe hyperkeratosis, displayed a high density of KLK8 mRNA on northern and in situ hybridisation analyses. The signals were localised in granular and spinous layers of lesional skin in all hyperkeratic samples, including the area surrounding the horn pearls of squamous cell carcinoma. To examine the relation between mRNA expression and terminal differentiation, the expression of KLK8 mRNA was analysed in cell cultures. When keratinisation proceeded in high calcium medium, a correlative increase in the expression of KLK8 mRNA was observed.

CONCLUSION

The results are consistent with a role for this protease in the terminal differentiation of keratinocytes.

Transforming growth factor-beta gene polymorphism in sarcoidosis and tuberculosis patients

SETTING

Transforming growth factor-beta (TGF-beta) plays an important role in many diseases, influencing as it does such processes as immune responses, fibrosing processes, and angiogenesis. Recently, polymorphisms have been described for TGF-beta that are associated with the risk of several diseases. In this study, we investigated whether TGF-beta 1 polymorphism has an effect on sarcoidosis and tuberculosis.

OBJECTIVE

TGF-beta 1 Codon 10 T869C polymorphism was investigated in 110 healthy control subjects, 104 sarcoidosis patients, and 101 tuberculosis patients.

DESIGN

The TGF-beta genotype was determined using polymerase chain reaction restriction fragment length polymorphism.

RESULTS

We found no significant differences in TGF-beta genotypes between sarcoidosis patients and healthy controls or tuberculosis patients and controls. The long axis of the tuberculin skin test was larger in the CC type compared with the CT type. However, there was no association between the TGF-beta genotype and the roentgenographic stage, the disappearance of shadows, or organ involvement in sarcoidosis, nor any association between genotype, the extent or type of roentgenographic shadow, or detected volume of tubercle bacilli in tuberculosis.

CONCLUSION

From the results, we believe that TGF-beta polymorphisms on the whole do not have a strong influence on disease onset or clinical progression in sarcoidosis and tuberculosis, although this polymorphism might have an effect on the immune response in a tuberculosis host.

False positive uptake of metaiodobenzylguanidine in hepatocellular carcinoma

We present the case of a patient who showed increased accumulation of (123)I-metaiodobenzylguanidine (MIBG) in hepatocellular carcinoma, leading to a false presumptive diagnosis of intrahepatic neuroendocrine tumour. The increase in uptake was not seen on images obtained 4 h after tracer injection but was evident on those taken after 24 h, suggesting slower washout from the liver tumour than from non-tumoural liver parenchyma. Our observations indicate that a non-neuroendocrine malignant tumour may exhibit high accumulation of MIBG associated with prolonged retention.

Self-oscillating polymer chain in a laser field

We have investigated the dynamical behaviour of the rhythmic conformational change between the folded compact state and the unfolded state in a single polymer chain under thermodynamically open conditions. It is shown that the spontaneous rhythmic change in the conformation of a single polymer chain (T4DNA, 166 kbp, contour length: 56 microns) is generated using a focused continuous wave (CW) Nd:YAG laser beam (wavelength lambda = 1064 nm), where the focused laser beam plays a dual role, both trapping a polymer chain at the focus and creating a temperature gradient around the focus. Furthermore, the whole process of the rhythmic conformational change: the course of melting, nucleation and growth between the folded and unfolded states has been clarified. The rhythmic change in the conformation is discussed in terms of the limit-cycle oscillation driven by the dissipation of the photon energy.