Lasting cortical activation after repetitive TMS of the motor cortex: a glucose metabolic study

OBJECTIVE: Cerebral [18F]fluorodeoxy-D-glucose PET ([18F]FDG-PET) was used to visualize the lasting neuronal activation after repetitive transcranial magnetic stimulation (rTMS) over the left hand area of the primary motor cortex (M1HAND). BACKGROUND: Applied over M1HAND, rTMS has been shown to produce a modulation of corticomotor excitability beyond the time of stimulation itself. METHODS: Eight right-handed subjects underwent nonquantitative [18F]FDG-PET measurements during two experimental conditions: at rest and after focal subthreshold 5-Hz rTMS over the left M1HAND. In the post-rTMS condition, [18F]FDG was injected immediately after the administration of 1,800 magnetic pulses over the left M1HAND. Relative differences in normalized regional cerebral metabolic rate of glucose (normalized rCMRglc) between conditions were determined using a voxel-by-voxel Student's t-test and volume-of-interest (VOI) analysis. Analysis was a priori restricted to the M1HAND, the supplementary motor area (SMA), and the primary auditory cortex of both hemispheres. RESULTS: A 5-Hz rTMS of the left M1HAND caused a lasting relative increase in normalized rCMRglc within the M1HAND bilaterally and the SMA. The magnitude and the topographic pattern of persisting relative rCMRglc increases within these motor cortical areas demonstrated considerable interindividual variations. CONCLUSIONS: Subthreshold 5-Hz repetitive transcranial magnetic stimulation (rTMS) over the hand area of the primary motor cortex is associated with a persisting neuronal activation in a distinct set of motor cortical areas beyond the time of stimulation. The current findings demonstrate that [18F]FDG-PET can localize and quantify regional net changes in synaptic cortical activity after rTMS and thus might elucidate the mechanisms underlying rTMS-associated therapeutic effects.     

Immunomagnetic enrichment, genomic characterization, and prognostic impact of circulating melanoma cells.

PURPOSE: The finding of melanoma cells in the peripheral blood, thus far mainly inferred from the PCR-based demonstration of tyrosinase mRNA, has been associated with metastatic melanoma. Neither the malignant nature nor the prognostic significance of circulating cells could be established. To address this question, we analyzed immunomagnetically isolated circulating melanoma cells for chromosomal aberrations and performed a clinical follow-up study of the enrolled patients. EXPERIMENTAL DESIGN: In a prospective study, blood samples were taken from 164 melanoma patients and 50 donors without malignant disease. Circulating melanoma cells were enriched by immunomagnetic cell sorting using a murine monoclonal antibody against the melanoma-associated chondroitin sulfate proteoglycan. To prove the malignant origin of the positive cells and to define their chromosomal aberrations, we analyzed the genomes of 15 individually isolated cells from seven patients by single-cell comparative genomic hybridization (SCOMP). RESULTS: Absolute and relative frequencies of circulating melanoma cells were associated with stage and with the presence or absence of detectable tumor. The detection of two or more cells correlated significantly with a reduced survival of patients with metastatic melanoma. All of the cells that were analyzed by SCOMP displayed multiple chromosomal changes and carried aberrations typical for melanoma. CONCLUSIONS: Immunomagnetic enrichment enables isolation and genomic characterization of circulating melanoma cells. The prognostic impact on survival of metastatic patients apparently reflects the aggressiveness of an ongoing tumor spread. Direct genomic analysis of the enriched and isolated cells will help to clarify the molecular-genetic basis of the establishment of generalized melanoma.     

Laminin-5 γ2-chain expression and DNA ploidy as predictors of prognosis in endometrial carcinoma

Expression of the laminin-5 γ2-chain in carcinoma cells has been implicated in tumor invasion. The aim was to investigate the expression and prognostic significance of the In-5 γ2-chain compared with clinicopathological factors and tumor cell DNA ploidy in endometrial carcinoma. Histological specimens from 80 endometrial carcinomas were examined with respect to immunohistochemical In-5 γ2-chain expression and correlated to the clinicopathological characteristics, DNA ploidy, and survival. Sixty-eight of 80 investigated cases were judged to be positive for the In-5 γ2-chain. Ln-5 γ2-chain did not show any correlation to stage, histopathological subtype, grade, and DNA ploidy. In univariate analyses, advanced stage (p<0.001), nonendometrioid carcinoma (p=0.030), low grade (p<0.001), aneuploid tumors (p<0.001), and In-5 γ2-chain expression (p=0.017) were highly associated with poor survival. Aneuploid tumors in combination with strong In-5 γ2-chain expression were significant predictors (p<0.001) of poor prognosis. In multivariate analyses including stage, histopathological subgroup, grade, DNA ploidy, and In-5 γ2-chain expression, all lost their significant prognostic information except for stage (p<0.001) and grade (p<0.05). Ln-5 γ2-chain expression and DNA ploidy both as a single parameter and in combination were demonstrated to be significant prognostic factors in univariate analysis. However, stage and grade provided more useful clinical information beyond histopathological subgroup, DNA ploidy, and In-5 γ2-chain expression. The results also indicate that In-5 γ2-chain expression is upregulated during the progression of endometrial carcinoma.     

Detection and clinical implications of early systemic tumor cell dissemination in breast cancer.

Blood-borne distant metastasis is the leading cause of cancer-related death in breast cancer. The onset of this fundamental process can now be assessed in cancer patients using ultrasensitive immunocytochemical and molecular assays able to detect even single metastatic cells. Analyses of bone marrow (BM) samples show that disseminated cells are present in 20-40% of primary breast cancer patients without any clinical or histopathological signs of metastasis. The common homing of circulating breast cancer cells in BM is indicative for systemic tumor cell spread and predictive for growth of overt metastases in relevant organ sites such as bone, lung, or liver. Recent clinical studies involving more than 3000 breast cancer patients demonstrated that the presence of tumor cells in BM at primary diagnosis is an independent prognostic factor for unfavorable clinical outcome. To date, sampling of BM, however, is not a routine procedure in clinical management of breast cancer patients. Therefore, several research groups have developed sensitive assays for detection of circulating tumor cells in peripheral blood. Studies evaluating the clinical relevance of these blood assays are ongoing. Here, we will review the existing tumor cell assays and discuss their current clinical relevance and perspectives for the clinical management of breast cancer patients.     

Effect of Systemic Pretreatment With Betamethasone on the Bacterial Flora,Inflammatory Response,and Polyp Formation in Experimentally Infected Rabbit Maxillary Sinus Mucosa

To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation.     

Correlation between basic fibroblast growth factor immunostaining of stromal cells and stromelysin-3 mRNA expression in human breast carcinoma.

We examined the localization of basic fibroblast growth factor (bFGF) in a series of human breast carcinomas using immunohistochemistry. Staining was observed in tumour cells in 15 out of 54 (28%) tumours and in the adjacent stroma in 34 out of 54 (63%) tumours examined. No correlation was observed between positive staining of these two compartments. The relationship between bFGF staining and expression of the metalloprotease stromelysin-3, and between bFGF and microvessel density, was examined. A statistically significant correlation (P < 0.003) was observed between bFGF staining of the stromal compartment and high expression of stromelysin-3 (ST-3; MMP-11) metalloprotease mRNA by stromal cells. In contrast, no correlation was observed between bFGF and intratumour microvessel density (IMD). These results raise the possibility that bFGF may be involved in the induction of stromelysin-3 mRNA expression in breast cancer stroma.     

The effect of soy isoflavones on the development of intestinal neoplasia in Apc mouse

Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in Apc^Min mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control, a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice.     

Valve repair in mitral regurgitation complicated by severe annulus calcification

BACKGROUND: Valvuloplasty has significant advantages over valve replacement for mitral regurgitation, but the presence of severe calcification of the mitral valve apparatus has been thought to preclude successful valve reconstruction in general. The purpose of this report is to assess the results of valvuloplasty in patients with severe mitral regurgitation having extensive calcification extending from the mitral annulus to underlying myocardium and parts of the papillary muscles. METHODS: Thirty-seven adult patients with severe mitral regurgitation and calcification were operated on between April 1990 and January 1998. Twenty-six patients had degenerative disease, 4 had acute bacterial endocarditis, 6 had postrheumatic fever, and 1 patient had Marfan's disease. The valve repair comprised of en bloc decalcification with extensive leaflet debridement and reconstruction of the annulus. Autologous pericardium was used in patch-extended endocardial annuloplasty or leaflet repair. Valve competence was retained after correction of regurgitation by sliding atrioplasty, rotation paracommissural sliding plasty, cusp remodeling, or chordal repair. All patients required a prosthetic annuloplasty. RESULTS: Follow-up echocardiography at 47 months (range, 3 to 92 months) showed no or only trivial mitral regurgitation in 33 patients; 3 had grade I-II mitral regurgitation and 1 required valve replacement after 3 months. Freedom of reoperation at 1 and 5 years was 94.6%. At last examination, 33 patients were in New York Heart Association functional class I and 3 in class I-II; there has been no mortality and no thromboembolic events. CONCLUSIONS: Valvuloplasty can be safely and successfully carried out in patients suffering from regurgitation associated with severe calcification of the mitral apparatus. With encouraging beneficial midterm results, we suggest patients with calcified valves should not be excluded from mitral repair.     

High stem cell frequency in acute myeloid leukemia at diagnosis predicts high minimal residual disease and poor survival.

PURPOSE: In CD34-positive acute myeloid leukemia (AML), the leukemia-initiating event originates from the CD34(+)CD38(-) stem cell compartment. Survival of these cells after chemotherapy may lead to minimal residual disease (MRD) and subsequently to relapse. Therefore, the prognostic impact of stem cell frequency in CD34-positive AML was investigated. EXPERIMENTAL DESIGN: First, the leukemogenic potential of unpurified CD34(+)CD38(-) cells, present among other cells, was investigated in vivo using nonobese diabetic/severe combined immunodeficient mice transplantation experiments. Second, we analyzed whether the CD34(+)CD38(-) compartment at diagnosis correlates with MRD frequency after chemotherapy and clinical outcome in 92 AML patients. RESULTS: In vivo data showed that engraftment of AML blasts in nonobese diabetic/severe combined immunodeficient mice directly correlated with stem cell frequency of the graft. In patients, a high percentage of CD34(+)CD38(-) stem cells at diagnosis significantly correlated with a high MRD frequency, especially after the third course of chemotherapy. Also, it directly correlated with poor survival. In contrast, total CD34(+) percentage showed no such correlations. CONCLUSIONS: Both in vivo data, as well as the correlation studies, show that AML stem cell frequency at diagnosis offers a new prognostic factor. From our data, it is tempting to hypothesize that a large CD34(+)CD38(-) population at diagnosis reflects a higher percentage of chemotherapy-resistant cells that will lead to the outgrowth of MRD, thereby affecting clinical outcome. Ultimately, future therapies should be directed toward malignant stem cells.     

Tumor lymphangiogenesis in inflammatory breast carcinoma: a histomorphometric study.

PURPOSE: At the time of diagnosis, metastatic dissemination of tumor cells via the lymphatic system has occurred in nearly all patients with inflammatory breast cancer (IBC). The objective of this study was twofold: (a) to determine which is the most suitable marker of lymph vessels in primary breast tumors and (b) to compare histomorphometric lymph vessel variables in IBC and non-IBC. EXPERIMENTAL DESIGN: Serial sections of 10 IBCs and 10 non-IBCs were immunostained for D2-40, LYVE-1, podoplanin, and PROX-1. Relative lymph vessel area, lymph vessel perimeters, and counts and lymphatic endothelial cell proliferation (LECP) were then measured in D2-40/Ki-67 double-immunostained sections of 10 normal breast tissues, 29 IBCs, and 56 non-IBCs. RESULTS: D2-40 was the most suitable antibody for staining peritumoral and intratumoral lymph vessels. D2-40-stained intratumoral lymph vessels were present in 80% of non-IBCs and 82.8% of IBCs (P = 0.76). In non-IBC, lymph vessels located in the tumor parenchyma were smaller and less numerous than those at the tumor periphery (P < 0.0001) whereas in IBC, intratumoral and peritumoral variables were not significantly different. The mean relative tumor area occupied by lymph vessels was larger in IBC than in non-IBC (P = 0.01). LECP at the tumor periphery was higher in IBC than in non-IBC: median LECP was 5.74% in IBC versus 1.83% in non-IBC (P = 0.005). CONCLUSIONS: The high LECP in IBC suggests that lymphangiogenesis contributes to the extensive lymphatic spread of IBC.