Biomedical subjects

Tomio Inoue

Publications and source records attributed to Tomio Inoue.

At least 19 recordsLinked to original sources

PubMed2007

Reverse perfusion-metabolism mismatch predicts good prognosis in patients undergoing cardiac resynchronization therapy: a pilot study.

BACKGROUND: Cardiac resynchronization therapy (CRT) improves glucose metabolism in the septum of patients with heart failure, so in the present study the predictive value of combined fluorodeoxyglucose (FDG)-positron emission tomography (PET) and metoxy-isobutyl isonitrile (MIBI)-single photon emission computed tomography (SPECT) for the prognosis of patients undergoing CRT was investigated. METHODS AND RESULTS: Fourteen patients (70.3+/-8.2 years) who underwent FDG-PET and MIBI-SPECT before implantation of a biventricular pacemaker were enrolled. The total number of matches, mismatches, reverse mismatches, summed difference score (SDS: sum total of FDG - MIBI scores) and SDS per segment (%SDS) in each of 5 areas of myocardium (septum, anterior, lateral, inferior area, apex) was calculated and compared between the survival groups (all survival: survival group; survival without ischemic heart disease (IHD): non-IHD survival group) and non-survival group. Both the number of reverse mismatch segments and the %SDS in the septum in the non-IHD survival group were significantly greater than in the non-survival group (3.2+/-1.6 vs 0.5+/-0.6, p<0.05; 0.62+/-0.61 vs -0.11+/-0.19, p<0.05). The receiver-operating characteristics curves for prognosis showed that the area under the curve for the number of reverse mismatch segments in the septum (0.93; confidence interval 0.61-0.98) was significantly greater. CONCLUSION: A reverse mismatch pattern in the septum can predict a good prognosis for patients treated with CRT.

Aged↗

PubMed2006

[Approximation of collimator scatter factor Sc by a saturation model].

To more easily estimate accurate values of collimator scatter facor, S(c), we suggest a two-component saturation model that accounts for scatter from the primary collimator and flattening filter and from the collimator jaws. This model, which assumes an exponential distribution of scatter intensity, was tested by in-air measurements using a mini-phantom for 4 MV and 10 MV X-rays of a Clinac 2100 C/D linear accelerator. The results showed a good fit of this model to our measured data (R(2)>0.9993). When the measured value was divided into the primary collimator/flattening filter component and the collimator jaw component, as expected, the former component showed a rapid and full saturation curve with increased field size, while the latter showed an almost linearly increasing curve. Therefore, we think that this saturation model is useful for the estimation of S(c) and is applicable to monitor unit calculation for an asymmetric field.

Filtration↗

PubMed2006

Postnatal changes of local neuronal circuits involved in activation of jaw-closing muscles.

Feeding behaviour in mammals changes from suckling to mastication during postnatal development and the neuronal circuits controlling feeding behaviour should change in parallel to the development of orofacial structures. In this review we discuss the location of excitatory premotor neurons for jaw-closing motoneurons (JCMNs) and postnatal changes of excitatory synaptic transmission from the supratrigeminal region (SupV) to JCMNs. We show that neurons located in SupV and the reticular formation dorsal to the facial nucleus most likely excite JCMNs. Excitatory inputs from SupV to JCMNs are mediated by activation of glutamate and glycine receptors in neonatal rats, whereas glycinergic inputs from SupV to JCMNs become inhibitory with age. We also show that the incidence of post-spike afterdepolarization increases during postnatal development, whereas the amplitude and half-duration of the medium-duration afterhyperpolarization decrease with age. Such postnatal changes in synaptic transmission from SupV to JCMNs and membrane properties of JCMNs might be involved in the transition from suckling to mastication.

Animals↗

PubMed2006

Targeted molecular imaging in oncology.

Improvement of scintigraphic tumor imaging is extensively determined by the development of more tumor specific radiopharmaceuticals. Thus, to improve the differential diagnosis, prognosis, planning and monitoring of cancer treatment, several functional pharmaceuticals have been developed. Application of molecular targets for cancer imaging, therapy and prevention using generator-produced isotopes is the major focus of ongoing research projects. Radionuclide imaging modalities (positron emission tomography, PET; single photon emission computed tomography, SPECT) are diagnostic cross-sectional imaging techniques that map the location and concentration of radionuclide-labeled radiotracers. 99mTc- and 68Ga-labeled agents using ethylenedicysteine (EC) as a chelator were synthesized and their potential uses to assess tumor targets were evaluated. 99mTc (t1/2 = 6 hr, 140 keV) is used for SPECT and 68Ga (t1/2 = 68 min, 511 keV) for PET. Molecular targets labeled with Tc-99m and Ga-68 can be utilized for prediction of therapeutic response, monitoring tumor response to treatment and differential diagnosis. Molecular targets for oncological research in (1) cell apoptosis, (2) gene and nucleic acid-based approach, (3) angiogenesis (4) tumor hypoxia, and (5) metabolic imaging are discussed. Numerous imaging ligands in these categories have been developed and evaluated in animals and humans. Molecular targets were imaged and their potential to redirect optimal cancer diagnosis and therapeutics were demonstrated.

Drug Delivery Systems↗

PubMed2006

Correlation between plasma brain natriuretic peptide concentration and lung thallium-201 uptake on exercise thallium perfusion images.

The plasma brain natriuretic peptide (BNP) concentration at rest correlates with left ventricular end-diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and pulmonary capillary wedge pressure (PCWP). High lung thallium-201 uptake has been reported to be associated with hemodynamic variables such as LVEDP, LVEF, and PCWP. However, there is no study that has investigated the correlation of plasma BNP concentration with lung thallium-201 uptake. We examined whether the plasma BNP concentration was related to lung thallium-201 uptake. Before exercise, venous blood samples were obtained from 39 patients with old myocardial infarction. We investigated the correlations between plasma BNP concentration and lung thallium-201 uptake, and whether they were related to LVEF, extent of nonviable myocardium, and ischemic myocardium, respectively, with thallium-201 exercise stress testing. The plasma BNP concentration significantly correlated with lung thallium-201 uptake (P < 0.05), nonviable segments (P < 0.01), and LVEF (P < 0.01). Lung thallium-201 uptake correlated with nonviable segments (P < 0.01). Our results suggest that increased secretion of BNP is related to increased lung thallium-201 uptake, and they are related to the extent of nonviable myocardium and decreased left ventricular function. Plasma BNP concentration and lung thalium-201 uptake may reflect the extent of myocardial fibrosis causing myocyte stretch.

Aged↗

PubMed2006

Development of an orthotopic transplantation model in nude mice that simulates the clinical features of human lung cancer.

The objective of the present study was to establish an orthotopic tumor transplantation model in nude mice that closely resembles the clinical features of human lung cancer. The human lung adenocarcinoma A549 cell line and the squamous cell carcinoma SQ5 cell line were used. Tumor cells suspended in serum-free medium were injected directly into the main bronchi of anesthetized female Balb/c athymic nude mice (7-9 weeks old) with or without simultaneous administration of 0.01 M ethylenediaminetetracetic acid (EDTA). In some experiments, lung carcinoma cells harvested from tumors transplanted subcutaneously were recultured and used for intratracheal implantation. Tumor nodules that formed in the lung were counted and confirmed by histological examination. Administration of A549 cells with EDTA resulted in a 70% engraftment rate (n = 10). Recultured A549 cells without and with EDTA resulted in 20% (n = 5) and 80% (n = 5) engraftment rates, respectively. Administration of SQ5 cells without or with EDTA formed 50% (n = 4) and 67% (n = 6) engraftment rates, respectively. Recultured SQ5 cells with EDTA further increased the engraftment rate to 100% (n = 6). Multiple tumors formed mainly in the left lung and the upper lobe of the right lung. Simultaneous administration of EDTA resulted in greater numbers of tumor nodules in the lung. Histological findings revealed that A549 tumor nodules were distributed primarily in alveoli. The SQ5 solid tumors invaded bronchioles and occupied the alveoli. This reproducible orthotopic transplantation model produced tumor growth that simulated the clinical features of human lung cancer.

Adenocarcinoma, Bronchiolo-Alveolar↗

PubMed2006

Evaluation of myocardial glucose metabolism before and after recovery of myocardial function in patients with tachycardia-induced cardiomyopathy.

BACKGROUND: We assessed left ventricular (LV) function and myocardial glucose metabolism by fluoro-18-deoxyglucose (18F-FDG) positron emission tomography (PET) in patients with tachycardia-induced cardiomyopathy (TC). METHODS: The subjects were 42 patients with heart disease, consisting of 7 patients with TC (61.4 +/- 19.0 years, LVEF 34.1%+/- 10.6%) and 35 with ischemic heart disease (IHD) (63.1 +/- 10.8 years, LVEF 49.9%+/- 13.5%). Five volunteers with normal ECG were the control group. All of the patients underwent 18F-FDG PET and echocardiography, and all of the patients with TC underwent 18F-FDG PET and echocardiography before and 6 months after antitachycardia therapy. Six patients underwent radiofrequency catheter ablation (RFCA) and 1 patient was medically treated with antitachycardia therapy. Myocardial glucose metabolism was assessed semiquantitatively by using the % dose uptake of 60 kg of BW (% dose uptake). RESULTS: Mean % dose uptake of the control group was 5.52 +/- 0.54%. After antitachycardia therapy, LVEF significantly improved (34.1 +/- 10.6% vs 54.3 +/- 13.6%, P < 0.01), and % dose uptake also significantly improved (1.26 +/- 0.55% vs 1.49 +/- 0.62%, P < 0.05). Patients with IHD showed higher % dose uptake than those with TC before antitachycardia therapy (3.18 +/- 1.36 vs 1.26 +/- 0.55%, P < 0.01), controls showed higher value of % dose uptake than TC before antitachycardia therapy (5.52 +/- 0.54% vs 1.26 +/- 0.55%, P < 0.01). CONCLUSION: Semiquantitative analysis of 18F-FDG PET showed that antitachycardia therapy improved myocardial glucose metabolism in patients with TC.

Cardiomyopathies↗

PubMed2006

Enhancement of splenic glucose metabolism during acute malarial infection: correlation of findings of FDG-PET imaging with pathological changes in a primate model of severe human malaria.

In the current study, to elucidate the clinical features of severe malaria, we performed whole-body positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) of Plasmodium coatneyi-infected acute-phase Japanese macaques. The infected monkeys clearly exhibited increase in splenic FDG uptake indicating marked enhancement of glucose metabolism. The standardized uptake values (SUVs) of the spleen in the infected monkeys were significantly higher than those in the uninfected monkey. At autopsy, splenomegaly was clearly present in all infected monkeys, and histopathologic findings included hyperplasia of lymphoid follicles in white pulp, a large number of activated macrophage, and congestion of parasitized red blood cells (PRBCs) and malaria pigments in red pulp. We suggest that increase in splenic glucose uptake may thus be closely related to activation of splenic clearance system against blood-stage malarial parasites.

Animals↗

PubMed2005

Input-output organization of jaw movement-related areas in monkey frontal cortex.

The brain mechanisms underlying mastication are not fully understood. To address this issue, we analyzed the distribution patterns of cortico-striatal and cortico-brainstem axon terminals and the origin of thalamocortical and intracortical fibers by injecting anterograde/retrograde tracers into physiologically and morphologically defined jaw movement-related cortical areas. Four areas were identified in the macaque monkey: the primary and supplementary orofacial motor areas (MIoro and SMAoro) and the principal and deep parts of the cortical masticatory area (CMaAp and CMaAd), where intracortical microstimulation produced single twitch-like or rhythmic jaw movements, respectively. Tracer injections into these areas labeled terminals in the ipsilateral putamen in a topographic fashion (MIoro vs. SMAoro and CMaAp vs. CMaAd), in the lateral reticular formation and trigeminal sensory nuclei contralaterally (MIoro and CMaAp) or bilaterally (SMAoro) in a complex manner of segregation vs. overlap, and in the medial parabranchial and Kölliker-Fuse nuclei contralaterally (CMaAd). The MIoro and CMaAp received thalamic projections from the ventrolateral and ventroposterolateral nuclei, the SMAoro from the ventroanterior and ventrolateral nuclei, and the CMaAd from the ventroposteromedial nucleus. The MIoro, SMAoro, CMaAp, and CMaAd received intracortical projections from the ventral premotor cortex and primary somatosensory cortex, the ventral premotor cortex and rostral cingulate motor area, the ventral premotor cortex and area 7b, and various sensory areas. In addition, the MIoro and CMaAp received projections from the three other jaw movement-related areas. Our results suggest that the four jaw movement-related cortical areas may play important roles in the formation of distinctive masticatory patterns.

Animals↗

PubMed2005

Involvement of reticular neurons located dorsal to the facial nucleus in activation of the jaw-closing muscle in rats.

The location of excitatory premotor neurons for jaw-closing motoneurons was examined by the use of electrical and chemical stimulation and extracellular single-unit recording techniques in the anesthetized rat. Single-pulse electrical stimulation of the supratrigeminal region (SupV) and the reticular formation dorsal to the facial nucleus (RdVII) elicited masseter EMG response at mean (+/-SD) latencies of 2.22 +/- 0.59 ms and 3.10 +/- 1.14 ms, respectively. Microinjection (0.1-0.3 microl) of glutamate (50 mM) or kainate (0.5-100 microM) into RdVII increased masseter nerve activity in artificially ventilated and immobilized rats by 30.2 +/- 40.5% and 50.7 +/- 46.8% compared to baseline values, respectively. Forty reticular neurons were antidromically activated by stimulation of the ipsilateral trigeminal motor nucleus (MoV). Twenty neurons were found in RdVII, and the remaining 20 neurons were located in SupV, or areas adjacent to SupV or RdVII. Eleven neurons in RdVII responded to at least either passive jaw opening or light pressure applied to the teeth or tongue. Nine neurons responded to passive jaw opening. Five of the nine neurons responded to multiple stimulus categories. A monosynaptic excitatory projection from one neuron in RdVII was detected by spike-triggered averaging of the rectified masseter nerve activity. We suggest that reticular neurons in RdVII are involved in increasing masseter muscle activity and that excitatory premotor neurons for masseter motoneurons are likely located in this area. RdVII could be an important candidate for controlling activity of jaw-closing muscles via peripheral inputs.

Action Potentials↗

PubMed2005

Prostate cancer: a comparative study of 11C-choline PET and MR imaging combined with proton MR spectroscopy.

PURPOSE: Prostate cancer is difficult to visualise in its early stages using current imaging technology. The present study aimed to clarify the utility of 11C-choline PET for localising and evaluating cancer lesions in patients with prostate cancer by conducting a prospective comparison with magnetic resonance (MR) imaging combined with proton MR spectroscopy. METHODS: PET and MR imaging combined with proton MR spectroscopy were performed in 20 patients with prostate cancer. Correlations among the metabolite ratio of choline + creatine to citrate (Cho+Cr/Ci) on MR spectroscopy, serum PSA and maximum standardised uptake value (SUVmax) of (11)C-choline were assessed. The location of the primary lesion was assessed by the site of SUVmax and the laterality of the highest Cho+Cr/Ci ratio and confirmed by examination of surgical pathology specimens (n=16). RESULTS: PET exhibited a diagnostic sensitivity of 100% (20/20) for primary lesions, while the sensitivities of MR imaging and MR spectroscopy were 60% (12/20) and 65% (13/20), respectively. Weak linear correlations were observed between SUVmax and serum PSA (r=0.52, p<0.05), and between SUVmax and Cho+Cr/Ci ratio (r=0.49, p<0.05). Regarding the localisation of main primary lesions, PET results agreed with pathological findings in 13 patients (81%) (kappa=0.59), while MR spectroscopy results were in accordance with pathological findings in eight patients (50%) (kappa=0.11). CONCLUSION: This preliminary study suggests that 11C-choline PET may provide more accurate information regarding the localisation of main primary prostate cancer lesions than MR imaging/MR spectroscopy. A further clinical study of 11C-choline PET in a large number of patients suspected of prostate cancer will be necessary to determine the clinical utility of 11C-choline PET in patients who clinically require biopsy.

Aged↗

PubMed2005

Stimulation of the nucleus locus coeruleus/subcoeruleus suppresses visceromotor responses to colorectal distention in the rat.

The aim of the present study was to examine whether the nucleus locus coeruleus/subcoeruleus (LC/SC) modulates visceromotor function. In the present study, an electromyogram (EMG) of the external abdominal oblique muscle evoked by colorectal distention was measured as a visceromotor reflex response, and inhibitory effects of LC/SC stimulation were estimated by the decrease of EMG activity. Under halothane anesthesia (1% in air), graded colorectal distentions (30, 60 or 80 mmHg) were produced by inflating a balloon inside the descending colon and rectum. A bipolar EMG electrode was inserted into the left external abdominal oblique muscle to record the EMG response to colorectal distention. Colorectal distention at a pressure of 30 mmHg did not evoke any EMG activity in the external abdominal oblique muscle in all rats tested. Electrical stimulation of the LC/SC (30, 50 and 70 microA, 100 Hz, 0.1 ms pulses) reduced EMG responses evoked by colorectal distention to 60 and 80 mmHg. LC/SC stimulation was effective both ipsilaterally and contralaterally indicating a bilateral effect. EMG responses decreased with an increase of LC/SC stimulation intensity. Following recordings of the inhibitory effects of LC/SC stimulation, lesions of the LC/SC ipsilateral to the EMG recording site were induced; 1 h after lesions the inhibitory effects of LC/SC stimulation were examined again. LC/SC stimulation did not reduce the EMG responses when LC/SC stimulation was applied to the ipsilateral LC/SC, whereas EMG responses were observed by stimulation of the intact LC/SC contralateral to the EMG recording site. From lesion experiments, it could be considered that suppression of the visceromotor response to colorectal distention is due to activation of the LC/SC. The results suggest that the visceromotor function is under the control of the centrifugal pathways from the LC/SC.

Abdominal Muscles↗

PubMed2005

Bcl-2 inhibitors potentiate the cytotoxic effects of radiation in Bcl-2 overexpressing radioresistant tumor cells.

PURPOSE: Bcl-2, an inhibitor of apoptosis frequently shows elevated expression in human tumors, thus resulting in resistance to radiation therapy. Therefore, inhibiting Bcl-2 function may enhance the radiosensitivity of tumor cells. Tetrocarcin A (TC-A) and bcl-2 antisense oligonucleotides exhibit antitumor activity by inhibiting Bcl-2 function and transcription, respectively. We investigated whether these antitumor agents would enhance the cytotoxic effects of radiation in tumor cells overexpressing Bcl-2. METHODS AND MATERIALS: We used HeLa/bcl-2 cells, a stable Bcl-2-expressing cell line derived from wild-type HeLa (HeLa/wt) cells. Cells were incubated with TC-A and bcl-2 antisense oligonucleotides for 24 h after irradiation, and cell viability was then determined. Apoptotic cells were quantified by flow cytometric assay. RESULTS: The HeLa/bcl-2 cells were more resistant to radiation than HeLa/wt cells. At concentrations that are not inherently cytotoxic, both TC-A and bcl-2 antisense oligonucleotides increased the cytotoxic effects of radiation in HeLa/bcl-2 cells, but not in HeLa/wt cells. However, in HeLa/bcl-2 cells, additional treatment with TC-A in combination with radiation did not significantly increase apoptosis. CONCLUSIONS: The present results suggest that TC-A and bcl-2 antisense oligonucleotides reduce radioresistance of tumor cells overexpressing Bcl-2. Therefore, a combination of radiotherapy and Bcl-2 inhibitors may prove to be a useful therapeutic approach for treating tumors that overexpress Bcl-2.

Aminoglycosides↗

PubMed2005

Identification of the segmental artery feeding the anterior spinal artery: correlation between helical CT and angiography.

PURPOSE: We investigated whether identification of the segmental artery feeding the anterior spinal artery (ASA) is possible by single-slice helical CT. MATERIAL AND METHODS: Enhanced CT and angiography were performed in 14 patients with retroperitoneal, liver, or bone tumor. A single-slice helical CT scanner with 7 mm collimation and a 1.0 helical pitch was used. Scanning was started 25 to 30 sec after an intravenous injection of 100 ml of contrast medium at a rate of 3.0 ml/sec. RESULTS: We predicted the segmental artery feeding the ASA in all 14 patients using enhanced CT images. In 12 of the 14 patients, the segmental artery feeding the ASA was angiographically identified. In 7 of these 12 patients, the level of the segmental artery feeding the ASA identified on segmental arteriogram was the same level as that predicted by enhanced CT. In the remaining 5 patients, the level of the segmental artery feeding the ASA identified on segmental arteriogram was one level higher or lower than the predicted spinal level. CONCLUSION: We could identify the segmental artery feeding the ASA by detailed examination and interpretation of single-slice helical CT images.

Adult↗

PubMed2004

Persistent hindpaw inflammation produces coeruleospinal antinociception in the non-inflamed forepaw of rats.

In a rat model of unilateral hindpaw inflammation, it is unclear whether the coeruleospinal modulation system is active at spinal segments distant from the inflamed plantar region, such as the cervical segments. To clarify this query, in the present study we measured paw withdrawal latency (PWL) to thermal stimuli on four paws (both forepaws and both hindpaws) following induction of inflammation and compared PWLs between rats with bilateral lesions of the locus coeruleus/subcoeruleus (LC/SC) and rats with sham operation. Unilateral hindpaw inflammation was produced by a subcutaneous injection of carrageenan (2 mg in 0.15 ml saline). Prior to carrageenan injection, in all four paws, PWLs did not differ between the LC/SC-lesioned and the sham-operated rats. Four hours after carrageenan injection, PWLs in the inflamed left hindpaw decreased significantly in both the LC/SC-lesioned and the sham-operated rats. The decreased PWLs of the LC/SC-lesioned group were significantly shorter than those of the sham-operated group. These phenomena which were observed in the inflamed left hindpaw were also observed in the non-inflamed left forepaws. In the right forepaws and the right hindpaws, no significant change in PWL was observed between before and 4 h after injection in both the sham-operated and the LC/SC-lesioned rats. These results suggest that unilateral hindpaw inflammation activates the coeruleospinal modulation system and that this modulation system is active not only at the lumbar segments but also at the cervical level where spinal segments are distant from the inflamed plantar region.

Animals↗

PubMed2004

Value of 18F-FDG PET in the detection of peritoneal carcinomatosis.

PURPOSE: Peritoneal carcinomatosis can be difficult to diagnose using computed tomography (CT). The purpose of this study was to evaluate the role of 2-(fluorine 18) fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in the detection of peritoneal carcinomatosis. METHODS: We reviewed the CT and FDG PET radiological reports and clinical charts of 18 patients with peritoneal carcinomatosis and 17 cancer patients without peritoneal carcinomatosis. We also assessed FDG PET scans from 20 healthy volunteers as a baseline study. The maximum standardised uptake values (SUVmax) over peritoneal lesions in cancer patients and over the area of most intense intestinal uptake in healthy volunteers and cancer patients without peritoneal carcinomatosis were measured. RESULTS: The sensitivity and positive predictive value (PPV) of combined FDG PET and CT were superior to those of CT alone for the detection of peritoneal lesions (sensitivity: 66.7% vs 22.2%, p<0.025; PPV: 92.3% vs 50.0%, p<0.05). The most frequent pattern of FDG uptake in patients with peritoneal carcinomatosis was abnormally intense focal uptake near the abdominal wall. An SUVmax threshold of 5.1 produced a diagnostic accuracy of combined FDG PET and CT of 78%. The additional information provided by FDG PET allowed a more accurate diagnosis in 14 patients (40.0%), and led to alteration of the therapeutic strategy in five (14.3%) of the enrolled cancer patients. CONCLUSION: We found that use of an intra-abdominal FDG uptake cut-off value for SUVmax of >5.1 assists in the diagnosis of peritoneal carcinomatosis. FDG PET may play an important role in the clinical management of patients with suspected peritoneal carcinomatosis.

Carcinoma↗

PubMed2004

Spinal pathways mediating coeruleospinal antinociception in the rat.

In a previous study, we showed in rats that axons of some locus coeruleus/subcoeruleus (LC/SC) neurons involved in coeruleospinal modulation of nociception descend through the ipsilateral side of the spinal cord and cross the midline at spinal segmental levels. The present study was designed to investigate a possible spinal pathway of these descending axons from the LC/SC. Extracellular recordings were made from the left dorsal horn with a carbon filament electrode (4-6 M(omega)). To block impulses from the LC/SC which descend through spinal pathways ipsilateral to the recording sites, a hemisection of the spinal cord ipsilateral to the recording sites was performed at the C2 level with fine forceps in all rats tested. In these rats, responses of dorsal horn neurons to noxious heat (53 degrees C) applied to receptive fields were inhibited during electrical stimulation (100 microA, 100 Hz, 0.1 ms pulses) of the LC/SC. The transection of the dorsolateral funiculus contralateral to the recording sites did not affect LC/SC stimulation-produced inhibition. Following transection of the ventrolateral funiculus (VLF) contralateral to the recording sites, LC/SC stimulation failed to inhibit heat-evoked responses. These results suggest that interruption of descending inhibition from the LC/SC produced by the VLF transections is due to the blockage of axons descending in the ventrolateral quadrant of the spinal cord, but not in the dorsolateral quadrant.

Action Potentials↗

PubMed2004

The clinical relevance of thymic fluorodeoxyglucose uptake in pediatric patients after chemotherapy.

The purpose of this study was to clarify the clinical implications of thymic fluorodeoxyglucose (FDG) uptake after chemotherapy in pediatric patients with malignant disease. Twenty-two pediatric patients, aged 0-17 years (mean 7.0 years), who had undergone FDG positron emission tomography (PET) were examined retrospectively. A total of 48 FDG-PET scans of the 22 patients were reviewed. Seven PET scans were recorded before the initial chemotherapy, and the remaining 41 scans were conducted during and after chemotherapy. Thymic FDG uptake was evaluated using standardized uptake value (SUV) analysis. The effect of chemotherapy on thymic FDG uptake was assessed by comparing SUV before, during, and after chemotherapy. The change in thymic FDG uptake with increasing time after the completion of chemotherapy was also assessed. Clinical laboratory data including number of white blood cells (WBCs), erythrocytes (RBCs), platelets, plasma glucose level and differential white blood count were analyzed for their association with thymic FDG uptake. Thymic FDG uptake in patients during chemotherapy was significantly lower than that in patients before chemotherapy (mean+/-SD 1.71+/-0.48 vs 2.27+/-0.32, respectively, P<0.01). Thymic FDG uptake in patients after chemotherapy was significantly higher than that in patients during chemotherapy (mean+/-SD 2.74+/-0.70 vs 1.71+/-0.48, respectively, P<0.01). A significant relationship between thymic FDG uptake and interval after completion of chemotherapy (r=0.74, P<0.0001) was observed. Significant relationships between blood counts (WBCs, RBCs, and platelets) and thymic FDG uptake were also observed. Comparison of the differential white blood count and thymic FDG uptake revealed a significant relationship only with lymphocyte count. Thymic FDG uptake in pediatric patients after completion of chemotherapy should not be mistaken as recurrent or metastatic thymic malignancy. Thymic FDG uptake appears to be associated with thymic function or hematopoietic function in bone marrow. Interpretation of FDG-PET must be made with this consideration in mind.

Adolescent↗