Fluorescence visualization of the intersegmental plane by bronchoscopic instillation of indocyanine green into the targeted segmental bronchus: determination of the optimal settings

ObjectiveTo determine the appropriate amount of indocyanine green for bronchial insufflation.MethodsWe enrolled 20 consecutive patients scheduled for anatomical segmentectomy in the Kochi Medical School Hospital. After inducing general anesthesia, 6 to 60 mL of 200-fold-diluted indocyanine green (0.0125 mg/mL) was insufflated into the subsegmental bronchi in the targeted pulmonary segmental bronchus. The volume of the targeted pulmonary segments was calculated using preoperative computed tomography. Fluorescence spread in the segmental alveoli was visualized using a dedicated near-infrared thoracoscope.ResultsThe targeted segment was uniformly visualized by indocyanine green fluorescence in 16/20 (80.0%) cases after insufflating indocyanine green. A receiver operating characteristic curve indicated that the area under the curve was 0.984; the optimal cut-off volume of diluted indocyanine green for insufflation was 8.91% of the calculated targeted pulmonary segment volume.ConclusionsThe setting for indocyanine green insufflation was optimized for near-infrared fluorescence image-guided anatomical segmentectomy. By injecting the correct amount of indocyanine green, fluorescence-guided anatomical segmentation may be performed more appropriately.     

Overexpression of cyclin‐dependent kinase 4 protein in extramammary Paget's disease

Cyclin‐dependent kinase 4 and 6 (CDK4/6) plays an important role in cell cycle progression, and the CDK4/6–cyclin D1 complex controls the cell cycle transition from G₁ phase to S phase. CDK4 is enhanced in several types of cancers and CDK4/6 inhibitors attenuate the proliferation of several types of cancer in vitro/in vivo. The purpose of our study was to investigate the expression pattern of CDK4 and evaluate its clinical importance in extramammary Paget's disease (EMPD). Almost all EMPD tissues were positive for CDK4, and metastatic lesions had a similar immunostaining intensity to primary lesions. In addition, CDK4 protein levels were positively correlated with those of cyclin D1 protein. Taken together, CDK4 may assume a crucial role in EMPD progression.     

Hyperpolarized 129Xe MRI using isobutene as a new quenching gas

The use of a quenching gas, isobutene, with a low vapor pressure was investigated to enhance the utility of hyperpolarized ¹²⁹Xe (HP Xe) MRI. Xenon mixed with isobutene was hyperpolarized using a home‐built apparatus for continuously producing HP Xe. The isobutene was then readily liquefied and separated almost totally by continuous condensation at about 173 K, because the vapor pressure of isobutene (0.247 kPa) is much lower than that of Xe (157 kPa). Finally, the neat Xe gas was continuously delivered to mice by spontaneous inhalation. The HP Xe MRI was enhanced twofold in polarization level and threefold in signal intensity when isobutene was adopted as the quenching gas instead of N₂. The usefulness of the HP Xe MRI was verified by application to pulmonary functional imaging of spontaneously breathing mice, where the parameters of fractional ventilation (r_a) and gas exchange (f_D) were evaluated, aiming at future extension to preclinical studies. This is the first application of isobutene as a quenching gas for HP Xe MRI.     

Dysembryoplastic neuroepithelial tumor in the insular cortex. Three dimensional magnetoencephalographic localization of epileptic discharges

Abstract

A case of dysembryoplastic neuroepithelial tumor in the left insular cortex manifesting with intractable seizures is presented. The multichannel magnetoencephalography (MEG) localized equivalent current dipoles of epileptic discharges at the cerebral cortex adjacent to the tumor. The total removal of the tumor resulted in complete disappearance of seizures. This case demonstrated that multichannel MEG was useful in the three-dimensional localization of irritative zone in the concealed cortices such as inside the sylvian fissure. [Neural Res 1998; 20: 433–438]     

Serum levels of interleukin‐1α in patients with systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune systemic connective tissue disorder characterized by sclerotic change of the skin and multiple internal organs. Although the pathogenesis of this disorder is still unknown, overproduction of extracellular matrix proteins, including collagens and fibronectin, and aberrant immune activation may be involved in the mechanism. Interleukin (IL)‐1 is one of the key regulators of inflammatory response. IL‐1 is also involved in regulating connective tissue remodeling and cellular differentiation of epithelial and ectodermal cells. There are three major members of the IL‐1 family: IL‐1α, IL‐1β and IL‐1 receptor antagonist. IL‐1α was first described as a factor derived from keratinocytes that stimulates thymocyte proliferation. IL‐1α plays a crucial role in procollagen production by fibroblasts derived from patients with SSc. The present study was undertaken to investigate the serum levels of IL‐1α in patients with SSc. Serum samples were obtained from 66 Japanese patients with SSc and 19 healthy controls. Levels of serum IL‐1α were measured with a specific enzyme‐linked immunoassay kit. Mean serum levels were significantly higher in SSc patients than in those healthy control subjects. Moreover, contracture of phalanges was found at a significantly lower prevalence in SSc patients with elevated serum IL‐1α levels than those with normal levels. These results suggest that IL‐1α may play a role in the pathogenesis of SSc.